Quantifying the sensitivity of feedstock properties and process conditions on hydrochar yield, carbon content, and energy content.

PubMed

Li, Liang; Wang, Yiying; Xu, Jiting; Flora, Joseph R V; Hoque, Shamia; Berge, Nicole D

2018-08-01

Hydrothermal carbonization (HTC) is a wet, low temperature thermal conversion process that continues to gain attention for the generation of hydrochar. The importance of specific process conditions and feedstock properties on hydrochar characteristics is not well understood. To evaluate this, linear and non-linear models were developed to describe hydrochar characteristics based on data collected from HTC-related literature. A Sobol analysis was subsequently conducted to identify parameters that most influence hydrochar characteristics. Results from this analysis indicate that for each investigated hydrochar property, the model fit and predictive capability associated with the random forest models is superior to both the linear and regression tree models. Based on results from the Sobol analysis, the feedstock properties and process conditions most influential on hydrochar yield, carbon content, and energy content were identified. In addition, a variational process parameter sensitivity analysis was conducted to determine how feedstock property importance changes with process conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hydrothermal carbonization of municipal solid waste for carbon sequestration and energy generation

USDA-ARS?s Scientific Manuscript database

A fairly new, innovative technique, called hydrothermal carbonization (HTC), has the potential to change the way municipal solid waste (MSW) is managed. HTC is a wet, low temperature (180-350°C), low pressure (in a closed system) thermochemical waste treatment/conversion technology that has been sho...

Hydrothermal carbonization: modeling, final properties design and applications: a review

USDA-ARS?s Scientific Manuscript database

Active research on biomass hydrothermal carbonization (HTC) continues to demonstrate its advantages over other thermochemical processes, in particular the interesting benefits associated with carbonaceous solid products called hydrochar (HC). The areas of applications of HC range from biofuel to dop...

Hydrothermal carbonization of food waste and associated packaging materials for energy source generation.

PubMed

Li, Liang; Diederick, Ryan; Flora, Joseph R V; Berge, Nicole D

2013-11-01

Hydrothermal carbonization (HTC) is a thermal conversion technique that converts food wastes and associated packaging materials to a valuable, energy-rich resource. Food waste collected from local restaurants was carbonized over time at different temperatures (225, 250 and 275°C) and solids concentrations to determine how process conditions influence carbonization product properties and composition. Experiments were also conducted to determine the influence of packaging material on food waste carbonization. Results indicate the majority of initial carbon remains integrated within the solid-phase at the solids concentrations and reaction temperatures evaluated. Initial solids concentration influences carbon distribution because of increased compound solubilization, while changes in reaction temperature imparted little change on carbon distribution. The presence of packaging materials significantly influences the energy content of the recovered solids. As the proportion of packaging materials increase, the energy content of recovered solids decreases because of the low energetic retention associated with the packaging materials. HTC results in net positive energy balances at all conditions, except at a 5% (dry wt.) solids concentration. Carbonization of food waste and associated packaging materials also results in net positive balances, but energy needs for solids post-processing are significant. Advantages associated with carbonization are not fully realized when only evaluating process energetics. A more detailed life cycle assessment is needed for a more complete comparison of processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Symbiotic relationship between hydrothermal carbonization technology and anaerobic digestion for food waste in China.

PubMed

Zhou, Ying; Engler, Nils; Nelles, Michael

2018-07-01

Food waste (FW) is traditionally disposed through landfills and incineration in China. Nowadays, there are some promising methods, such as anaerobic digestion (AD) or feeding and composting, which are being applied in pilot cities. However, the inherent characteristics of Chinese FW may be regarded as a double-edged sword in the practical applications of these disposal methods. To overcome these challenges, two modes of the hydrothermal carbonization (HTC) process were reviewed as innovative strategies in this article. Meanwhile, the "symbiotic relationship" between Chinese FW and HTC technologies was highlighted. To improve treatment efficiency of FW, we should not only try different methods and develop existing technologies, but also pay more attention to the utilization and "1 + 1 > 2" synergistic effect of their combinations, such as the combination of HTC and AD as a co-treatment method for saving on the construction cost and avoiding redistribution of social resources. Copyright © 2018 Elsevier Ltd. All rights reserved.

Recovery of Macro and Micro-Nutrients by Hydrothermal Carbonization of Septage.

PubMed

McGaughy, Kyle; Reza, M Toufiq

2018-02-28

In this study, septic tank waste (i.e., septage) was hydrothermally carbonized (HTC) in order to recover macro and micronutrients, while tracking the fate of residual heavy metals. Three different HTC temperatures (i.e., 180, 220, and 260 °C) at autogenous pressures and two reaction times (i.e., 30 and 120 min) were applied on both solid and liquid septages. Hydrochar and HTC process liquids were characterized using ICP, CHNS, and UV-vis spectroscopy. Treatment at 260 °C for 120 min maximized ammonia recovery, producing a liquid with 1400 mg/L of ammonia. Overall, about 70% of available nitrogen ended up in the liquid phase as nitrate or ammonia. Solid hydrochars show potential for fertilizer use, with high phosphorus content of 100-130 kg/tonne. It was found that heavy metals mainly remained in the solid phase, although the concentrations of heavy metals are mostly lower than U.S. EPA regulation for biosolids with the exception of selenium.

Assessing the environmental impact of energy production from hydrochar generated via hydrothermal carbonization waste management

USDA-ARS?s Scientific Manuscript database

Hydrothermal carbonization (HTC) is a relatively low temperature thermal conversion process that is gaining significant attention as a sustainable and environmentally beneficial approach for the transformation of biomass and waste streams to value-added products. Although there are numerous studies ...

Evaluation of the performance of high temperature conversion reactors for compound-specific oxygen stable isotope analysis.

PubMed

Hitzfeld, Kristina L; Gehre, Matthias; Richnow, Hans-Hermann

2017-05-01

In this study conversion conditions for oxygen gas chromatography high temperature conversion (HTC) isotope ratio mass spectrometry (IRMS) are characterised using qualitative mass spectrometry (IonTrap). It is shown that physical and chemical properties of a given reactor design impact HTC and thus the ability to accurately measure oxygen isotope ratios. Commercially available and custom-built tube-in-tube reactors were used to elucidate (i) by-product formation (carbon dioxide, water, small organic molecules), (ii) 2nd sources of oxygen (leakage, metal oxides, ceramic material), and (iii) required reactor conditions (conditioning, reduction, stability). The suitability of the available HTC approach for compound-specific isotope analysis of oxygen in volatile organic molecules like methyl tert-butyl ether is assessed. Main problems impeding accurate analysis are non-quantitative HTC and significant carbon dioxide by-product formation. An evaluation strategy combining mass spectrometric analysis of HTC products and IRMS 18 O/ 16 O monitoring for future method development is proposed.

Pharmaceutical load in sewage sludge and biochar produced by hydrothermal carbonization.

PubMed

vom Eyser, C; Palmu, K; Schmidt, T C; Tuerk, J

2015-12-15

We investigated the removal of twelve pharmaceuticals in sewage sludge by hydrothermal carbonization (HTC), which has emerged as a technology for improving the quality of organic waste materials producing a valuable biochar material. In this study, the HTC converted sewage sludge samples to a biochar product within 4h at a temperature of 210 °C and a resulting pressure of about 15 bar. Initial pharmaceutical load of the sewage sludge was investigated as well as the residual concentrations in biochar produced from spiked and eight native sewage sludge samples from three waste water treatment plants. Additionally, the solid contents of source material and product were compared, which showed a considerable increase of the solid content after filtration by HTC. All pharmaceuticals except sulfamethoxazole, which remained below the limit of quantification, frequently occurred in the investigated sewage sludges in the μg/kg dry matter (DM) range. Diclofenac, carbamazepine, metoprolol and propranolol were detected in all sludge samples with a maximum concentration of 800 μg/kgDM for metoprolol. HTC was investigated regarding its contaminant removal efficiency using spiked sewage sludge. Pharmaceutical concentrations were reduced for seven compounds by 39% (metoprolol) to≥97% (carbamazepine). In native biochar samples the four compounds phenazone, carbamazepine, metoprolol and propranolol were detected, which confirmed that the HTC process can reduce the load of micropollutants. In contrast to the other investigated compounds phenazone concentration increased, which was further addressed in thermal behaviour studies including three structurally similar potential precursors. Copyright © 2015 Elsevier B.V. All rights reserved.

Properties of animal-manure based hydrochars and predictions using published models

USDA-ARS?s Scientific Manuscript database

In order to fully utilize hydrothermal carbonization (HTC) to produce value-added hydrochars from animal manures, it is important to understand how process conditions (e.g., temperature, reaction time, solids concentration) influence product characteristics. The effect of process conditions on the e...

Comparative Study of the Structure of Hydroproducts Derived from Loblolly Pine and Straw Grass

DOE PAGES

Wu, Qiong; Huang, Lang; Yu, Shitao; ...

2017-05-26

We investigated the structural characteristics of products derived from the hydrothermal carbonization (HTC) of loblolly pine (LP) and straw grass (SG) via solid-state cross-polarization/magic angle spinning nuclear magnetic resonance (CP/MAS 13C NMR), heteronuclear single-quantum correlation nuclear magnetic resonance (HSQC-NMR), and solution 13C NMR and 31P NMR techniques. Our results revealed that after HTC, hydrochars from both LP and SG mainly consisted of a combination of lignin, furfural, and condensed polyaromatic structures with a high level of fixed carbon content and higher heating value (HHV). Hydrochar from LP exhibited a higher aryl to furan ratio, and those from SG contained moremore » aliphatic functional groups. Solution 13C NMR and HSQC revealed that both liquid chemicals were condensed polyphenolic structures with aliphatic groups that exist mainly in the form of side chains. Although the LP products exhibited a higher proportion of aromatic structures, the types of polyphenol and aliphatic C–H were more diverse in the SG products. Results also indicated that reactions such as chain scission and condensation occurred during hydrothermal carbonization processes. Overall, HTC was found to be an effective refinery treatment for converting different waste biomass into valuable energy materials and chemicals.« less

Comparative Study of the Structure of Hydroproducts Derived from Loblolly Pine and Straw Grass

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

Wu, Qiong; Huang, Lang; Yu, Shitao

We investigated the structural characteristics of products derived from the hydrothermal carbonization (HTC) of loblolly pine (LP) and straw grass (SG) via solid-state cross-polarization/magic angle spinning nuclear magnetic resonance (CP/MAS 13C NMR), heteronuclear single-quantum correlation nuclear magnetic resonance (HSQC-NMR), and solution 13C NMR and 31P NMR techniques. Our results revealed that after HTC, hydrochars from both LP and SG mainly consisted of a combination of lignin, furfural, and condensed polyaromatic structures with a high level of fixed carbon content and higher heating value (HHV). Hydrochar from LP exhibited a higher aryl to furan ratio, and those from SG contained moremore » aliphatic functional groups. Solution 13C NMR and HSQC revealed that both liquid chemicals were condensed polyphenolic structures with aliphatic groups that exist mainly in the form of side chains. Although the LP products exhibited a higher proportion of aromatic structures, the types of polyphenol and aliphatic C–H were more diverse in the SG products. Results also indicated that reactions such as chain scission and condensation occurred during hydrothermal carbonization processes. Overall, HTC was found to be an effective refinery treatment for converting different waste biomass into valuable energy materials and chemicals.« less

Hydrothermal carbonization of autoclaved municipal solid waste pulp and anaerobically treated pulp digestate

USDA-ARS?s Scientific Manuscript database

In this study, the autoclaved organic fraction of municipal solid waste pulp (OFMSW) and the digestate from OFMSW pulp after anaerobic digestion (AD) were processed by hydrothermal carbonization (HTC) at 200, 250, and 300 °C for 30 min and 2 h. The focus of this work was to evaluate the potential fo...

Gaseous byproducts from high-temperature thermal conversion elemental analysis of nitrogen- and sulfur-bearing compounds with considerations for δ2H and δ18O analyses.

PubMed

Hunsinger, Glendon B; Tipple, Christopher A; Stern, Libby A

2013-07-30

High-temperature, conversion-reduction (HTC) systems convert hydrogen and oxygen in materials into H2 and CO for δ(2)H and δ(18)O measurements by isotope ratio mass spectrometry. HTC of nitrogen- and sulfur-bearing materials produces unintended byproduct gases that could affect isotope analyses by: (1) allowing isotope exchange reactions downstream of the HTC reactor, (2) creating isobaric or co-elution interferences, and (3) causing deterioration of the chromatography. This study characterizes these HTC byproducts. A HTC system (ThermoFinnigan TC/EA) was directly connected to a gas chromatograph/quadrupole mass spectrometer in scan mode (m/z 8 to 88) to identify the volatile products generated by HTC at conversion temperatures of 1350 °C and 1450 °C for a range of nitrogen- and sulfur-bearing solids [keratin powder, horse hair, caffeine, ammonium nitrate, potassium nitrate, ammonium sulfate, urea, and three nitrated organic explosives (PETN, RDX, and TNT)]. The prominent HTC byproduct gases include carbon dioxide, hydrogen cyanide, methane, acetylene, and water for all nitrogen-bearing compounds, as well as carbon disulfide, carbonyl sulfide, and hydrogen sulfide for sulfur-bearing compounds. The 1450 °C reactor temperature reduced the abundance of most byproduct gases, but increased the significant byproduct, hydrogen cyanide. Inclusion of a post-reactor chemical trap containing Ascarite II and Sicapent, in series, eliminated the majority of byproducts. This study identified numerous gaseous HTC byproducts. The potential adverse effects of these gases on isotope ratio analyses are unknown but may be mitigated by higher HTC reactor temperatures and purifying the products with a purge-and-trap system or with chemical traps. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

Hydrothermal Carbonization: a feasible solution to convert biomass to soil?

NASA Astrophysics Data System (ADS)

Tesch, Walter; Tesch, Petra; Pfeifer, Christoph

2013-04-01

The erosion of fertile soil is a severe problem arising right after peak oil (Myers 1996). That this issue is not only a problem of arid countries is shown by the fact that even the European Commission defined certain milestones to address the problem of soil erosion in Europe (European Commission 2011). The application of bio-char produced by torrefaction or pyrolysis for the remediation, revegetation and restoration of depleted soils started to gain momentum recently (Rillig 2010, Lehmann 2011, Beesley 2011). Hydrothermal carbonization (HTC) is a promising thermo-chemical process that can be applied to convert organic feedstock into fertile soil and water, two resources which are of high value in regions being vulnerable to erosion. The great advantage of HTC is that organic feedstock (e.g. organic waste) can be used without any special pretreatment (e.g. drying) and so far no restrictions have been found regarding the composition of the organic matter. By applying HTC the organic material is processed along a defined pathway in the Van Krevelen plot (Behrendt 2006). By stopping the process at an early stage a nutritious rich material can be obtained, which is known to be similar to terra preta. Considering that HTC-coal is rich in functional groups and can be derived from the process under "wet" conditions, it can be expected that it shall allow soil bacteria to settle more easily compared to the bio-char derived by torrefaction or pyrolysis. In addition, up to 10 tons process water per ton organic waste can be gained (Vorlop 2009). Thus, as organic waste, loss of fertile soil and water scarcity becomes a serious issue within the European Union, hydrothermal carbonization can provide a feasible solution to address these issues of our near future. The presentation reviews the different types of feedstock investigated for the HTC-Process so far and gives an overview on the current stage of development of this technology. References Beesley L., Moreno-Jiménez E., Gomez-Eyles J.L., Harris H., Robinson B., Sizmur T.: A review of biochars' potential role in the remediation, revegetation and restoration of contaminated soils. Environmental Pollution (159), p. 3269 - 3282, 2011. Behrendt F.: Direktverflüssigung von Biomasse - Reaktionsmechanismen und Produktverteilungen Institut für Energietechnik, Technische Universität Berlin Studie im Auftrag der Bundesanstalt für Landwirtschaft und Ernährung; Projektnummer 114-50-10-0337/05-B, 2006. European Commission: "Roadmap to a Resource Efficient Europe", COM(2011) 571. Lehmann J., Rillig M.C., Thies J., Masiello C.A., Hockaday W.C., Crowley D.: Biochar effects on soil biota - A review, Soil Biology & Biochemistry, p. 1-25, 2011. Myers Norman: "Environmental services of biodiversity", Proc. Natl. Acad. Sci. USA Vol 93, pp. 2764 - 2769, 1996. Rillig M.C., Wagner M., Salem M., Antunes P.M., George C., Ramke H.G., Titirici M.M., Antonietti M.: Material derived from hydrothermal carbonization: effects on plant growth and arbuscular mycorrhiza. Applied Soil Ecology (45), p. 238 - 242, 2010. Vorlop K.D., Schuchardt F., Prüße U.: Hydrothermale Carbonisierung Analyse und Ausblicke. FNR-Fachgespräch, Berlin, 2009.

Preparation of porous carbon sphere from waste sugar solution for electric double-layer capacitor

NASA Astrophysics Data System (ADS)

Hao, Zhi-Qiang; Cao, Jing-Pei; Wu, Yan; Zhao, Xiao-Yan; Zhuang, Qi-Qi; Wang, Xing-Yong; Wei, Xian-Yong

2017-09-01

Waste sugar solution (WSS), which contains abundant 2-keto-L-gulonic acid, is harmful to the environment if discharged directly. For value-added utilization of the waste resource, a novel process is developed for preparation of porous carbon spheres by hydrothermal carbonization (HTC) of WSS followed by KOH activation. Additionally, the possible preparation mechanism of carbon spheres is proposed. The effects of hydrothermal and activation parameters on the properties of the carbon sphere are also investigated. The carbon sphere is applied to electric double-layer capacitor and its electrochemical performance is studied. These results show that the carbon sphere obtained by HTC at 180 °C for 12 h with the WSS/deionized water volume ratio of 2/3 possess the highest specific capacitance under identical activation conditions. The specific capacitance of the carbon spheres can reach 296.1 F g-1 at a current density of 40 mA g-1. Besides, excellent cycle life and good capacitance retention (89.6%) are observed at 1.5 A g-1 after 5000 cycles. This study not only provides a facile and potential method for the WSS treatment, but also achieves the high value-added recycling of WSS for the preparation of porous carbon spheres with superior electrochemical properties.

Novel Tool for Simultaneous Carbon and Nitrogen Stable Isotope Analyses in Aqueous Samples

NASA Astrophysics Data System (ADS)

Federherr, E.; Schmidt, T. C.; Cerli, C.; Kalbitz, K.; Kupka, H. J.; Lange, L.; Dunsbach, R.; Panetta, R. J.; Kasson, A.

2014-12-01

Investigation of transformation and transport processes of carbon and nitrogen in ecosystems plays an important role to understand and predict their dynamics and role in biogeochemistry. Consequently, suitable and accurate methods for concentration as well as stable isotopic composition analysis of carbon and nitrogen in waters and aqueous solutions play a significant role. Traditionally dissolved carbon and nitrogen stable isotope analysis (SIA) is performed using either offline sample preparation followed by elemental analysis isotope ratio mass spectrometry (EA/IRMS) or modified wet chemical oxidation based device coupled to IRMS. Recently we presented a high temperature combustion system (HTC), which significantly improves upon these methods for dissolved organic carbon (DOC) SIA. The analysis of δ15N of dissolved nitrogen still has large limitations. Its low concentration makes EA/IRMS laborious, time and sample consuming. Systems based on wet chemical oxidation-IRMS bare the risk of sensitivity loss as well as of fractionation due to incomplete mineralization. In addition, the high solubility of molecular nitrogen in water remains a technical challenge, as it requires additional separation steps to distinguish between physically dissolved nitrogen and bound nitrogen. Further development of our HTC system lead to the implementation of the δ15N determination which now coupled, into a novel total organic carbon (TOC) analyzing system, especially designed for SIA of both, carbon and nitrogen. Integrated, innovative purge and trap technique (peak focusing) for nitrogen with aluminosilicate adsorber and peltier element based cooling system, in combination with high injection volume (up to 3 mL) as well as favorable carrier gas flow significantly improves sensitivity. Down to 1ppm and less total nitrogen can be measured with precision of ≤ 0.5‰. To lower the background caused by physically dissolved nitrogen new, membrane-vacuum based, degasser was designed for online separation of physically dissolved nitrogen. This novel HTC system, "iso TOC cube", provides an innovative tool with large potential in investigation of biogeochemical carbon and nitrogen cycles.

Analysis of de novo sequencing and transcriptome assembly and lignocellulolytic enzymes gene expression of Coriolopsis gallica HTC.

PubMed

Chen, Yuehong; Cao, Qinghua; Tao, Xiang; Shao, Huanhuan; Zhang, Kun; Zhang, Yizheng; Tan, Xuemei

2017-03-01

White-rot basidiomycete Coriolopsis gallica HTC is one of the main biodegraders of poplar. In our previous study, we have shown the strong capacity of C. gallica HTC to degrade lignocellulose. In this study, equal amounts of total RNA fromC. Gallica HTC cultures grown in different conditions were pooled together. Illumina paired-end RNA sequencing was performed, and 13.2 million 90-bp paired-end reads were generated. We chose the Merged Assembly of Oases data-set for the following blast searches and gene ontology analyses. The reads were assembled de novo into 28,034 transcripts (≥ 100 bp) using combined assembly strategy MAO. The transcripts were annotated using Blast2GO. In all, 18,810 transcripts (≥100 bp) achieved BLASTX hits, of which, 7048 transcripts had GO term and 2074 had ECs. The expression level of 11 lignocellulolytic enzyme genes from the assembled C. gallica HTC transcriptome were detected by real-time quantitative polymerase chain reaction. The results showed that expression levels of these genes were affected by carbon source and nitrogen source at the level of transcription. The current abundant transcriptome data allowed the identification of many new transcripts in C. gallica HTC. Data provided here represent the most comprehensive and integrated genomic resources for cloning and identifying genes of interest from C. gallica HTC. Characterization of C. gallica HTC transcriptome provides an effective tool to understand mechanisms underlying cellular and molecular functions of C. gallica HTC.

Short-term incubation studies on degradation of biochar in soil

NASA Astrophysics Data System (ADS)

Lanza, Giacomo; Wirth, Stephan; Geßler, Arthur; Kern, Jürgen; Mumme, Jan

2014-05-01

Biochar is considered a stable, recalcitrant substance, which holds potential to store carbon in soils for prolonged time and therefore would provide a long-term carbon sink. Furthermore, biochar is discussed to enhance soil fertility and plant productivity, and may improve water and nutrient holding capacity. However, mineralisation to CO2 may occur, as for any soil organic carbon pool, depending on char composition, soil properties and environmental conditions. Therefore, it is important to gain insight into the stability of its carbon structure and the dynamics of decay processes in soil. The evaluation of biochar stability in soil is complicated by the impact of external factors thus as soil moisture and temperature, soil nutrient status and moreover by extended decay timescales. To overcome these difficulties, we performed dynamic incubation experiments under laboratory conditions, using a multi-channel, automated infra-red gas analysis system at 20°C for up to 10 days to detect CO2 emission over time. Our aim was to compare the decay dynamics of different biochar preparations added to soil, i.e. HTC-char and pyrochar from maize silage with and without biological post-processing (anaerobic digestion), as compared to unmodified maize straw. Digestate from a maize silage-fed anaerobic biogas reactor was also tested. As a result, the addition of charred or digested materials to soil resulted in much lower CO2 emission rates as compared to the unmodified maize straw, proving stability of biochar carbon compounds. Pyrochar showed to be the most stable of all substrates added, as the CO2 emission was hardly distinguishable from that of the control soil. Soil enriched with HTC-char emitted significantly more CO2 compared to soil enriched with pyrochar, but the post-processing was effective in reducing the emissions. Furthermore, HTC-char showed a two-step decay kinetics, which cannot apparently be explained with a simple double-pool model. In conclusion, the short-term incubation approach was effective to highlight differences in decomposition dynamics between the considered substrates in soil, and confirmed the effectiveness of the charring process to increase the stability of organic substrates in soil. More investigations are necessary to reveal the impact of readily available substrates and nutrients on degradation of biochar in soil, and to clarify the mechanisms responsible for the observed kinetics in order to derive a suitable process model.

Hydrochar from sewage sludge and urban wastes as a peat replacement in growing media preparation

NASA Astrophysics Data System (ADS)

Álvarez, Maria Luisa; Méndez, Ana; Paz-Ferreiro, Jorge; Soler-Rovira, Pedro; García-Gil, Juan Carlos; Plaza, César; Gascó, Gabriel

2016-04-01

Nowadays, there is an important trend in Europe for peat replacement with biochar in growing media formulation in order to reduce the environmental impact of peat exploitation. Hydrothermal carbonization (HTC) is a thermochemical process of converting organic feedstock into a high carbon rich solid product named hydrochar. It is performed in water mild temperature (180-260°C) under pressure conditions (2-6MPa) for 5-250 min. The reaction pressure is not controlled in the process and is autogenic with the saturation vapour pressure of water corresponding to the reaction temperature. In recent years, the possibility of subjecting organic wastes to HTC has attracted the scientific community attention due to their interesting advantages over other thermal treatments such as pyrolysis, torrefaction or gasification. The aim of the present paper is to study the possible use of two hydrochars produced by Ingelia (Spain) from sewage sludge and urban waste treatment as growing media material in horticulture. For this, thermal, chemical and hydrophysical properties were determined and compared with that of brown commercial peat.

A comparative study for the organic byproducts from hydrothermal carbonizations of sugarcane bagasse and its bio-refined components cellulose and lignin.

PubMed

Du, Fang-Li; Du, Qi-Shi; Dai, Jun; Tang, Pei-Duo; Li, Yan-Ming; Long, Si-Yu; Xie, Neng-Zhong; Wang, Qing-Yan; Huang, Ri-Bo

2018-01-01

Sugarcane bagasse was refined into cellulose, hemicellulose, and lignin using an ethanol-based organosolv technique. The hydrothermal carbonization (HTC) reactions were applied for bagasse and its two components cellulose and lignin. Based on GC-MS analysis, 32 (13+19) organic byproducts were derived from cellulose and lignin, more than the 22 byproducts from bagasse. Particularly, more valuable catechol products were obtained from lignin with 56.8% share in the total GC-MS integral area, much higher than the 2.263% share in the GC-MS integral areas of bagasse. The organic byproducts from lignin make up more than half of the total mass of lignin, indicating that lignin is a chemical treasure storage. In general, bio-refinery and HTC are two effective techniques for the valorization of bagasse and other biomass materials from agriculture and forest industry. HTC could convert the inferior biomass to superior biofuel with higher energy quantity of combustion, at the same time many valuable organic byproducts are produced. Bio-refinery could promote the HTC reaction of biomass more effective. With the help of bio-refinery and HTC, bagasse and other biomass materials are not only the sustainable energy resource, but also the renewable and environment friendly chemical materials, the best alternatives for petroleum, coal and natural gas.

Nutrient retention and fate of iron-binding phenolic compounds during the injera processing of tannin-free and high-tannin sorghum.

PubMed

Seyoum, Yohannes; Retta, Negussie; Baye, Kaleab

2016-03-30

Traits such as bird-, insect- and mould-resistance are the focus in selecting improved sorghum varieties, but this often increases the tannin content, which can negatively affect iron bioavailability. The grain characteristics, nutrient retention, and the fate of iron-binding polyphenols (IBPs) during injera processing, an Ethiopian traditional fermented pancake, were investigated using agriculturally improved tannin-free (TFC) and high-tannin (HTC) sorghum cultivars. The HTC had significantly higher IBP contents than the TFC (P < 0.05). Decortication led to iron (24-27%), calcium (18-43%), IBP (catechol 35-41%, galloyl 35-42%), and tannin (12-35%) losses. Sourdough fermentation reduced the IBP and tannin concentrations in HTC, but had no effect on the IBP concentrations in TFC. The modified injera processing that included pre-soaking resulted in the highest IBP reductions (galloyl 73% and catechol 71%). Nutrient retention in HTC and TFC processing was different. Including a pre-soaking step during injera processing of HTC could counter the negative effects of IBP on iron absorption, while benefiting from the agronomic features of HTC. © 2015 Society of Chemical Industry.

Effect of hydrothermal carbonization on storage process of woody pellets: Pellets' properties and aldehydes/ketones emission.

PubMed

Li, Hui; Wang, Siyuan; Huang, Zhongliang; Yuan, Xingzhong; Wang, Ziliang; He, Rao; Xi, Yanni; Zhang, Xuan; Tan, Mengjiao; Huang, Jing; Mo, Dan; Li, Changzhu

2018-07-01

Effect of hydrothermal carbonization (HTC) on the hydrochar pelletization and the aldehydes/ketones emission from pellets during storage was investigated. Pellets made from the hydrochar were stored in sealed apparatuses for sampling. The energy consumption during pelletization and the pellets' properties before/after storage, including dimension, density, moisture content, hardness, aldehyde/ketones emission amount/rate and unsaturated fatty acid amount, were analyzed. Compared with untreated-sawdust-pellets, the hydrochar-pellets required more energy consumption for pelletization, and achieved the improved qualities, resulting in the higher stability degree during storage. The species and amount of unsaturated fatty acids in the hydrochar-pellets were higher than those in the untreated-sawdust-pellets. The unsaturated fatty acids content in the hydrochar-pellets was decreased with increasing HTC temperature. Higher aldehydes/ketones emission amount and rates with a longer emission period were found for the hydrochar-pellets, associated with variations of structure and unsaturated fatty acid composition in pellets. Copyright © 2018 Elsevier Ltd. All rights reserved.

Removal of Contaminant Nanoparticles from Wastewater Produced Via Hydrothermal Carbonization by SPIONs

NASA Astrophysics Data System (ADS)

Parsapour, Melika

Hydrothermal carbonization (HTC) is a chemical approach that can be defined as a combined dehydration and decarboxylation process in a wet state. Briefly, this process is performed by applying elevated temperature (between 180-250°C) and pressure (around 2MPa) to convert biomass from aqueous suspension (e.g. sludge, wastewater, natural products, among other) into three different phases and materials products, including biocoal. Further, during the wet conversion process the high residue content is transformed into nanoparticles that could present well-defined or heterogeneous nanostructure. Although HTC was known for years, it has been focused only recently due to exclusive products properties and cost-effective production. In fact, HTC has been used for sludge and wastewater treatment plants in some developed countries such as Germany. Nowadays, many scientific groups still investigate solid products (e.g. biocoal) from HTC. These studies are related to physico-chemical and biological characterization of HTC's generated materials, as well as their potential uses. However, aqueous products from HTC, which are rich in hydrocarbons derivatives and nanoparticles (NPs), are rarely studied. Thereby, our objective is to study the wastewater generated from HTC applied to samples of either glycerin or sugar. Furthermore, we propose a novel treatment strategy to remove the NPs from the wastewater. In this regard, we have used Superparamagnetic Iron Oxide (SPIONs) due to their unique physico-chemical properties (magnetic properties, adsorption capacity, biocompatibility and eco-friendly degradation) for decontamination of water and wastewater. In this regard, we synthesized two different nanocomposites based on SPIONs to carry out the magnetic removal of existent NPs in the wastewater. For the first case, we synthesized polyethylene-glycol (PEG) coated SPIONS (SPIONs PEG). The second one was a new nanocomposite (SPIONs/GO) obtained from in situ growth of SPIONS over purified graphene oxide (GO), which was afterwards coated with PEG (20000Da), resulting in SPIONs/GO PEG. As GO has various functional groups that have a high valence for absorption of contaminants due to their oxygen content, we assume that SPIONs/GO PEG improves the efficiency of the decontamination process compared to SPIONs PEG alone. Initially, we have characterized the synthetized SPIONs. Fourier Transform Infrared spectroscopy (FT-IR) was used to identify the present functional groups in the SPIONs samples. Atomic Force Microscopy (AFM) and Transmission Electronic Microscopy (TEM) were used to determine the topography and diameter size via high resolution images with fine details of the nanocomposites. Finally Dynamic Light Scattering (DLS) was used to evaluate the size distribution of the SPIONs in distilled water. Also, all wastewater samples were characterized before and after treatment. FT-IR was used to determine the functional groups in initial samples. Ultraviolet-visible spectroscopy (UV-vis) was used to observe the UV absorption of the chemicals. DLS was used for size distribution and density measurement, and morphology investigation was done by AFM technique. The SPIONs which involved the GO due to the presence of oxidizes groups showed a better ordered crystalline structure and a narrower diameter distribution. The glycerin samples treated by SPIONs PEG and SPIONs/GO PEG demonstrated 43% and 38% reduction in contaminant respectively. As for the sugar samples, the reductions were of 33% and 60% respectively. Thus, the obtained results confirm the capability of the nanocomposites to remove the nano contaminant from wastewater samples reasonably. However, the decontamination power of the nanocomposites differs accordingly to the chemical structure of the initial biomass.

Effect of hydrothermal carbonization on migration and environmental risk of heavy metals in sewage sludge during pyrolysis.

PubMed

Liu, Tingting; Liu, Zhengang; Zheng, Qingfu; Lang, Qianqian; Xia, Yu; Peng, Nana; Gai, Chao

2018-01-01

The heavy metals distribution during hydrothermal carbonization (HTC) of sewage sludge, and pyrolysis of the resultant hydrochar was investigated and compared with raw sludge pyrolysis. The results showed that HTC reduced exchangeable/acid-soluble and reducible fraction of heavy metals and lowered the potential risk of heavy metals in sewage sludge. The pyrolysis favored the transformation of extracted/mobile fraction of heavy metals to residual form especially at high temperature, immobilizing heavy metals in the chars. Compared to the chars from raw sludge pyrolysis, the chars derived from hydrochar pyrolysis was more alkaline and had lower risk and less leachable heavy metals, indicating that pyrolysis imposed more positive effect on immobilization of heavy metals for the hydrochar than for sewage sludge. The present study demonstrated that HTC is a promising pretreatment prior to pyrolysis from the perspective of immobilization of heavy metals in sewage sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

The distinctive microbial community improves composting efficiency in a full-scale hyperthermophilic composting plant.

PubMed

Yu, Zhen; Tang, Jia; Liao, Hanpeng; Liu, Xiaoming; Zhou, Puxiong; Chen, Zhi; Rensing, Christopher; Zhou, Shungui

2018-06-07

The application of conventional thermophilic composting (TC) is limited by poor efficiency. Newly-developed hyperthermophilic composting (HTC) is expected to overcome this shortcoming. However, the characterization of microbial communities associated with HTC remains unclear. Here, we compared the performance of HTC and TC in a full-scale sludge composting plant, and found that HTC running at the hyperthermophilic and thermophilic phases for 21 days, led to higher composting efficiency and techno-economic advantages over TC. Results of high-throughput sequencing showed drastic changes in the microbial community during HTC. Thermaceae (35.5-41.7%) was the predominant family in the hyperthermophilic phase, while the thermophilic phase was dominated by both Thermaceae (28.0-53.3%) and Thermoactinomycetaceae (29.9-36.1%). The change of microbial community could be the cause of continuous high temperature in HTC, and thus improve composting efficiency by accelerating the maturation process. This work has provided theoretical and practical guidance for managing sewage sludge by HTC. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hydrothermal carbonization of livestock mortality for the reduction of pathogens and microbially-derived DNA

USDA-ARS?s Scientific Manuscript database

Hydrothermal carbonization (HTC), utilizing high temperature and pressure, has the potential to treat agricultural waste and inactivate pathogens, antibiotic resistance genes (ARG), and contaminants of emerging concern (CEC) in an environmentally and economically friendly manner. Livestock mortality...

Validation of GC-IRMS techniques for δ13C and δ2H CSIA of organophosphorus compounds and their potential for studying the mode of hydrolysis in the environment.

PubMed

Wu, Langping; Kümmel, Steffen; Richnow, Hans H

2017-04-01

Compound-specific stable isotope analysis (CSIA) is among the most promising tools for studying the fate of organic pollutants in the environment. However, the feasibility of multidimensional CSIA was limited by the availability of a robust method for precise isotope analysis of heteroatom-bearing organic compounds. We developed a method for δ 13 C and δ 2 H analysis of eight organophosphorus compounds (OPs) with different chemical properties. In particular, we aimed to compare high-temperature conversion (HTC) and chromium-based HTC (Cr/HTC) units to explore the limitations of hydrogen isotope analysis of heteroatom-bearing compounds. Analysis of the amount dependency of the isotope values (linearity analysis) of OPs indicated that the formation of HCl was a significant isotope fractionation process leading to inaccurate δ 2 H analysis in HTC. In the case of nonchlorinated OPs, by-product formation of HCN, H 2 S, or PH 3 in HTC was observed but did not affect the dynamic range of reproducible isotope values above the limit of detection. No hydrogen-containing by-products were found in the Cr/HTC process by use of ion trap mass spectrometry analysis. The accuracy of gas chromatography - isotope ratio mass spectrometry was validated in comparison with elemental analyzer - isotope ratio mass spectrometry. Dual-isotope fractionation yielded Λ values of 0 ± 0 at pH 7, 7 ± 1 at pH 9, and 30 ± 6 at pH 12, indicating the potential of 2D CSIA to characterize the hydrolysis mechanisms of OPs. This is the first report on the combination of δ 2 H and δ 13 C isotope analysis of OPs, and this is the first study providing a systematic evaluation of HTC and Cr/HTC for hydrogen isotope analysis using OPs as target compounds. Graphical Abstract Comparison of δ 2 H measurement of non-chlorinated and chlorinated OPs via GC-Cr/HTC-IRMS and GC-HTC-IRMS system.

A Primer on High-Throughput Computing for Genomic Selection

PubMed Central

Wu, Xiao-Lin; Beissinger, Timothy M.; Bauck, Stewart; Woodward, Brent; Rosa, Guilherme J. M.; Weigel, Kent A.; Gatti, Natalia de Leon; Gianola, Daniel

2011-01-01

High-throughput computing (HTC) uses computer clusters to solve advanced computational problems, with the goal of accomplishing high-throughput over relatively long periods of time. In genomic selection, for example, a set of markers covering the entire genome is used to train a model based on known data, and the resulting model is used to predict the genetic merit of selection candidates. Sophisticated models are very computationally demanding and, with several traits to be evaluated sequentially, computing time is long, and output is low. In this paper, we present scenarios and basic principles of how HTC can be used in genomic selection, implemented using various techniques from simple batch processing to pipelining in distributed computer clusters. Various scripting languages, such as shell scripting, Perl, and R, are also very useful to devise pipelines. By pipelining, we can reduce total computing time and consequently increase throughput. In comparison to the traditional data processing pipeline residing on the central processors, performing general-purpose computation on a graphics processing unit provide a new-generation approach to massive parallel computing in genomic selection. While the concept of HTC may still be new to many researchers in animal breeding, plant breeding, and genetics, HTC infrastructures have already been built in many institutions, such as the University of Wisconsin–Madison, which can be leveraged for genomic selection, in terms of central processing unit capacity, network connectivity, storage availability, and middleware connectivity. Exploring existing HTC infrastructures as well as general-purpose computing environments will further expand our capability to meet increasing computing demands posed by unprecedented genomic data that we have today. We anticipate that HTC will impact genomic selection via better statistical models, faster solutions, and more competitive products (e.g., from design of marker panels to realized genetic gain). Eventually, HTC may change our view of data analysis as well as decision-making in the post-genomic era of selection programs in animals and plants, or in the study of complex diseases in humans. PMID:22303303

Multi-threaded integration of HTC-Vive and MeVisLab

NASA Astrophysics Data System (ADS)

Gunacker, Simon; Gall, Markus; Schmalstieg, Dieter; Egger, Jan

2018-03-01

This work presents how Virtual Reality (VR) can easily be integrated into medical applications via a plugin for a medical image processing framework called MeVisLab. A multi-threaded plugin has been developed using OpenVR, a VR library that can be used for developing vendor and platform independent VR applications. The plugin is tested using the HTC Vive, a head-mounted display developed by HTC and Valve Corporation.

Speciation evolution of zinc and copper during pyrolysis and hydrothermal carbonization treatments of sewage sludges

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

Huang, Rixiang; Zhang, Bei; Saad, Emily M.

Thermal and hydrothermal treatments are promising techniques for sewage sludge management that can potentially facilitate safe waste disposal, energy recovery, and nutrient recovery/recycling. Content and speciation of heavy metals in the treatment products affect the potential environmental risks upon sludge disposal and/or application of the treatment products. Therefore, it is important to study the speciation transformation of heavy metals and the effects of treatment conditions. By combining synchrotron X-ray spectroscopy/microscopy analysis and sequential chemical extraction, this study systematically characterized the speciation of Zn and Cu in municipal sewage sludges and their chars derived from pyrolysis (a representative thermal treatment technique)more » and hydrothermal carbonization (HTC; a representative hydrothermal treatment technique). Spectroscopy analysis revealed enhanced sulfidation of Zn and Cu by anaerobic digestion and HTC treatments, as compared to desulfidation by pyrolysis. Overall, changes in the chemical speciation and matrix properties led to reduced mobility of Zn and Cu in the treatment products. These results provide insights into the reaction mechanisms during pyrolysis and HTC treatments of sludges and can help evaluate the environmental/health risks associated with the metals in the treatment products.« less

Biochar Treatment Resulted in a Combined Effect on Soybean Growth Promotion and a Shift in Plant Growth Promoting Rhizobacteria

PubMed Central

Egamberdieva, Dilfuza; Wirth, Stephan; Behrendt, Undine; Abd_Allah, Elsayed F.; Berg, Gabriele

2016-01-01

The application of biochar to soil is considered to have the potential for long-term soil carbon sequestration, as well as for improving plant growth and suppressing soil pathogens. In our study we evaluated the effect of biochar on the plant growth of soybeans, as well as on the community composition of root-associated bacteria with plant growth promoting traits. Two types of biochar, namely, maize biochar (MBC), wood biochar (WBC), and hydrochar (HTC) were used for pot experiments to monitor plant growth. Soybean plants grown in soil amended with HTC char (2%) showed the best performance and were collected for isolation and further characterization of root-associated bacteria for multiple plant growth promoting traits. Only HTC char amendment resulted in a statistically significant increase in the root and shoot dry weight of soybeans. Interestingly, rhizosphere isolates from HTC char amended soil showed higher diversity than the rhizosphere isolates from the control soil. In addition, a higher proportion of isolates from HTC char amended soil compared with control soil was found to express plant growth promoting properties and showed antagonistic activity against one or more phytopathogenic fungi. Our study provided evidence that improved plant growth by biochar incorporation into soil results from the combination of a direct effect that is dependent on the type of char and a microbiome shift in root-associated beneficial bacteria. PMID:26941730

Effects of Tai Chi exercise on blood pressure and plasma levels of nitric oxide, carbon monoxide and hydrogen sulfide in real-world patients with essential hypertension.

PubMed

Pan, Xiaogui; Zhang, Yi; Tao, Sai

2015-01-01

Objective was to investigate the effects of Tai Chi exercise on nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) levels, and blood pressure (BP) in patients with essential hypertension (EH). EH patients were assigned to the Tai Chi exercise group (HTC, n = 24), and hypertension group (HP, n = 16) by patients' willingness. Healthy volunteers matched for age and gender were recruited as control (NP, n = 16). HTC group performed Tai Chi (60 min/d, 6 d/week) for 12 weeks. Measurements (blood glucose, cholesterol, NO, CO, H2S and BP) were obtained at week 0, 6, and 12. SBP, MAP, and low-density lipoprotein cholesterol levels decreased, and high-density lipoprotein cholesterol levels increased by week 12 in the HTC group (all p < 0.05 versus baseline). Plasma NO, CO, and H2S levels in the HTC group were increased after 12 weeks (all p < 0.05 versus baseline). SBP, DBP and MAP levels were significantly lower in the HTC than in the HP group (all p < 0.05). However, no changes were observed in the HP and NP groups. Correlations were observed between changes in SBP and changes in NO, CO and H2S (r = -0.45, -0.51 and -0.46, respectively, all p < 0.05), and between changes in MAP and changes in NO, CO and H2S (r = -0.36, -0.45 and -0.42, respectively, all p < 0.05). In conclusion, Tai Chi exercise seems to have beneficial effects on BP and gaseous signaling molecules in EH patients. However, further investigation is required to understand the exact mechanisms underlying these observations, and to confirm these results in a larger cohort.

Mixing HTC and HPC Workloads with HTCondor and Slurm

NASA Astrophysics Data System (ADS)

Hollowell, C.; Barnett, J.; Caramarcu, C.; Strecker-Kellogg, W.; Wong, A.; Zaytsev, A.

2017-10-01

Traditionally, the RHIC/ATLAS Computing Facility (RACF) at Brookhaven National Laboratory (BNL) has only maintained High Throughput Computing (HTC) resources for our HEP/NP user community. We’ve been using HTCondor as our batch system for many years, as this software is particularly well suited for managing HTC processor farm resources. Recently, the RACF has also begun to design/administrate some High Performance Computing (HPC) systems for a multidisciplinary user community at BNL. In this paper, we’ll discuss our experiences using HTCondor and Slurm in an HPC context, and our facility’s attempts to allow our HTC and HPC processing farms/clusters to make opportunistic use of each other’s computing resources.

Process Design and Techno-economic Analysis for Materials to Treat Produced Waters.

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

Heimer, Brandon Walter; Paap, Scott M; Sasan, Koroush

Significant quantities of water are produced during enhanced oil recovery making these “produced water” streams attractive candidates for treatment and reuse. However, high concentrations of dissolved silica raise the propensity for fouling. In this paper, we report the design and economic analysis for a new ion exchange process using calcined hydrotalcite (HTC) to remove silica from water. This process improves upon known technologies by minimizing sludge product, reducing process fouling, and lowering energy use. Process modeling outputs included raw material requirements, energy use, and the minimum water treatment price (MWTP). Monte Carlo simulations quantified the impact of uncertainty and variabilitymore » in process inputs on MWTP. These analyses showed that cost can be significantly reduced if the HTC materials are optimized. Specifically, R&D improving HTC reusability, silica binding capacity, and raw material price can reduce MWTP by 40%, 13%, and 20%, respectively. Optimizing geographic deployment further improves cost competitiveness.« less

Uptake contexts and perceived impacts of HIV testing and counselling among adults in East and Southern Africa: A meta-ethnographic review.

PubMed

Witzel, T Charles; Lora, Wezzie; Lees, Shelley; Desmond, Nicola

2017-01-01

HIV testing and counselling (HTC) interventions are key to controlling the HIV epidemic in East and Southern Africa where HTC is primarily delivered through voluntary counselling and testing (VCT), provider initiated testing and counselling (PITC), and home-based counselling and testing (HBVCT). Decision making processes around uptake of HTC models must be taken into account when designing new interventions. Counselling in HTC aims to reduce post-test risk taking behaviour and to link individuals to care but its efficacy is unclear. This meta-ethnography aims to understand the contexts of HTC uptake in East and Southern Africa and to analyse the perceived impacts of counselling-based interventions in relation to sexual behaviour and linkage to care. We conducted a systematic literature review of studies investigating HTC in East and Southern Africa from 2003 -April 2014. The search and additional snowballing identified 20 studies that fit our selection criteria. These studies were synthesised through a thematic framework analysis. Twenty qualitative and mixed-methods studies examining impacts of HTC models in East and Southern Africa were meta-synthesised. VCT decisions were made individually while HBVCT decisions were located in family and community units. PITC was associated with coercion from healthcare providers. Low quality counselling components and multiple-intersecting barriers faced by individuals mean that counselling in HTC was not perceived to be effective in reducing post-test risk behaviour and had limited perceived effect in facilitating linkage to care. HBVCT is associated with minimal stigma and should be considered as an area of priority. Counselling components in HTC interventions were effective in transmitting information about HIV and sexual risk, but were perceived as ineffective in addressing the broader personal circumstances preventing sexual behaviour change and modulating access to care.

Use of two varieties of hard-to-cook beans (Phaseolus vulgaris) and cowpeas (Vigna unguiculata) in the processing of koki (a steamed legume product).

PubMed

Mbofung, C M; Rigby, N; Waldron, K

1999-01-01

Koki is a nutritious cowpea-based food product usually processed by steam cooking whipped cowpea (Vigna unguiculata) paste mixed with spices and palm oil. A study was carried out to investigate the effect of the partial replacement of cowpeas (CP) with hard-to-cook (HTC) beans on the chemical, nutritional and sensory characteristics of koki. Towards this objective, two varieties of beans--Phaseolus vulgaris (red kidney beans--RKB and mottled brown beans--MBB), each with the HTC defect, were separately incorporated into cowpea paste in the following Bean:CP ratios 0:100, 20:80, 30:70, 40:60, 50:50, 60:40 and processed into koki. Incorporation of dry HTC beans into cowpeas in the making of koki affected the bulking properties of the uncooked paste, the nutrient composition, essential amino acid content, antinutritional factors, digestibility as well as the sensory attributes of cooked koki. Sensory tests showed that a highly acceptable, nutritious and digestible koki can be processed from cowpeas partially replaced with dry HTC bean paste up to levels of about 40-50% depending on the variety of dry bean used.

Selection criteria for oxidation method in total organic carbon measurement.

PubMed

Yoon, GeunSeok; Park, Sang-Min; Yang, Heuiwon; Tsang, Daniel C W; Alessi, Daniel S; Baek, Kitae

2018-05-01

During the measurement of total organic carbon (TOC), dissolved organic carbon is converted into CO 2 by using high temperature combustion (HTC) or wet chemical oxidation (WCO). However, the criteria for selecting the oxidation methods are not clear. In this study, the chemical structures of organic material were considered as a key factor to select the oxidation method used. Most non-degradable organic compounds showed a similar oxidation efficiency in both methods, including natural organic compounds, dyes, and pharmaceuticals, and thus both methods are appropriate to measure TOC in waters containing these compounds. However, only a fraction of the carbon in the halogenated compounds (perfluorooctanoic acid and trifluoroacetic acid) were oxidized using WCO, resulting in measured TOC values that are considerably lower than those determined by HTC. This result is likely due to the electronegativity of halogen elements which inhibits the approach of electron-rich sulfate radicals in the WCO, and the higher bond strength of carbon-halogen pairs as compared to carbon-hydrogen bonds, which results in a lower degree of oxidation of the compounds. Our results indicate that WCO could be used to oxidize most organic compounds, but may not be appropriate to quantify TOC in organic carbon pools that contain certain halogenated compounds. Copyright © 2018 Elsevier Ltd. All rights reserved.

Risk factors for service use and trends in coverage of different HIV testing and counselling models in northwest Tanzania between 2003 and 2010.

PubMed

Cawley, Caoimhe; Wringe, Alison; Todd, Jim; Gourlay, Annabelle; Clark, Benjamin; Masesa, Clemens; Machemba, Richard; Reniers, Georges; Urassa, Mark; Zaba, Basia

2015-11-01

To investigate the relative effectiveness of different HIV testing and counselling (HTC) services in improving HIV diagnosis rates and increasing HTC coverage in African settings. Patient records from three HTC services [community outreach HTC during cohort study rounds (CO-HTC), walk-in HTC at the local health centre (WI-HTC) and antenatal HIV testing (ANC-HTC)] were linked to records from a community cohort study using a probabilistic record linkage algorithm. Characteristics of linked users of each HTC service were compared to those of cohort participants who did not use the HTC service using logistic regression. Data from three cohort study rounds between 2003 and 2010 were used to assess trends in the proportion of persons testing at different service types. The adjusted odds ratios for HTC use among men with increasing numbers of sexual partners in the past year, and among HIV-positive men and women compared to HIV-negative men and women, were higher at WI-HTC than at CO-HTC and ANC-HTC. Among sero-survey participants, the largest numbers of HIV-positive men and women learned their status via CO-HTC. However, we are likely to have underestimated the numbers diagnosed at WI-HTC and ANC-HTC, due to low sensitivity of the probabilistic record linkage algorithm. Compared to CO-HTC or ANC-HTC, WI-HTC was most likely to attract HIV-positive men and women, and to attract men with greater numbers of sexual partners. Further research should aim to optimise probabilistic record linkage techniques, and to investigate which types of HTC services most effectively link HIV-positive people to treatment services relative to the total cost per diagnosis made. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Home-based versus mobile clinic HIV testing and counseling in rural Lesotho: a cluster-randomized trial.

PubMed

Labhardt, Niklaus Daniel; Motlomelo, Masetsibi; Cerutti, Bernard; Pfeiffer, Karolin; Kamele, Mashaete; Hobbins, Michael A; Ehmer, Jochen

2014-12-01

The success of HIV programs relies on widely accessible HIV testing and counseling (HTC) services at health facilities as well as in the community. Home-based HTC (HB-HTC) is a popular community-based approach to reach persons who do not test at health facilities. Data comparing HB-HTC to other community-based HTC approaches are very limited. This trial compares HB-HTC to mobile clinic HTC (MC-HTC). The trial was powered to test the hypothesis of higher HTC uptake in HB-HTC campaigns than in MC-HTC campaigns. Twelve clusters were randomly allocated to HB-HTC or MC-HTC. The six clusters in the HB-HTC group received 30 1-d multi-disease campaigns (five villages per cluster) that delivered services by going door-to-door, whereas the six clusters in MC-HTC group received campaigns involving community gatherings in the 30 villages with subsequent service provision in mobile clinics. Time allocation and human resources were standardized and equal in both groups. All individuals accessing the campaigns with unknown HIV status or whose last HIV test was >12 wk ago and was negative were eligible. All outcomes were assessed at the individual level. Statistical analysis used multivariable logistic regression. Odds ratios and p-values were adjusted for gender, age, and cluster effect. Out of 3,197 participants from the 12 clusters, 2,563 (80.2%) were eligible (HB-HTC: 1,171; MC-HTC: 1,392). The results for the primary outcomes were as follows. Overall HTC uptake was higher in the HB-HTC group than in the MC-HTC group (92.5% versus 86.7%; adjusted odds ratio [aOR]: 2.06; 95% CI: 1.18-3.60; p = 0. 011). Among adolescents and adults ≥ 12 y, HTC uptake did not differ significantly between the two groups; however, in children <12 y, HTC uptake was higher in the HB-HTC arm (87.5% versus 58.7%; aOR: 4.91; 95% CI: 2.41-10.0; p<0.001). Out of those who took up HTC, 114 (4.9%) tested HIV-positive, 39 (3.6%) in the HB-HTC arm and 75 (6.2%) in the MC-HTC arm (aOR: 0.64; 95% CI: 0.48-0.86; p = 0.002). Ten (25.6%) and 19 (25.3%) individuals in the HB-HTC and in the MC-HTC arms, respectively, linked to HIV care within 1 mo after testing positive. Findings for secondary outcomes were as follows: HB-HTC reached more first-time testers, particularly among adolescents and young adults, and had a higher proportion of men among participants. However, after adjusting for clustering, the difference in male participation was not significant anymore. Age distribution among participants and immunological and clinical stages among persons newly diagnosed HIV-positive did not differ significantly between the two groups. Major study limitations included the campaigns' restriction to weekdays and a relatively low HIV prevalence among participants, the latter indicating that both arms may have reached an underexposed population. This study demonstrates that both HB-HTC and MC-HTC can achieve high uptake of HTC. The choice between these two community-based strategies will depend on the objective of the activity: HB-HTC was better in reaching children, individuals who had never tested before, and men, while MC-HTC detected more new HIV infections. The low rate of linkage to care after a positive HIV test warrants future consideration of combining community-based HTC approaches with strategies to improve linkage to care for persons who test HIV-positive. ClinicalTrials.gov NCT01459120. Please see later in the article for the Editors' Summary.

Determination of heat transfer coefficient for an interaction of sub-cooled gas and metal

NASA Astrophysics Data System (ADS)

Zaidi Sidek, Mohd; Syahidan Kamarudin, Muhammad

2016-02-01

Heat transfer coefficient (HTC) for a hot metal surface and their surrounding is one of the need be defined parameter in hot forming process. This study has been conducted to determine the HTC for an interaction between sub-cooled gas sprayed on a hot metal surface. Both experiments and finite element have been adopted in this work. Initially, the designated experiment was conducted to obtain temperature history of spray cooling process. Then, an inverse method was adopted to calculate the HTC value before we validate in a finite element simulation model. The result shows that the heat transfer coefficient for interaction of subcooled gas and hot metal surface is 1000 W/m2K.

Uptake contexts and perceived impacts of HIV testing and counselling among adults in East and Southern Africa: A meta-ethnographic review

PubMed Central

Witzel, T. Charles; Lora, Wezzie; Lees, Shelley; Desmond, Nicola

2017-01-01

Introduction HIV testing and counselling (HTC) interventions are key to controlling the HIV epidemic in East and Southern Africa where HTC is primarily delivered through voluntary counselling and testing (VCT), provider initiated testing and counselling (PITC), and home-based counselling and testing (HBVCT). Decision making processes around uptake of HTC models must be taken into account when designing new interventions. Counselling in HTC aims to reduce post-test risk taking behaviour and to link individuals to care but its efficacy is unclear. This meta-ethnography aims to understand the contexts of HTC uptake in East and Southern Africa and to analyse the perceived impacts of counselling-based interventions in relation to sexual behaviour and linkage to care. Methods We conducted a systematic literature review of studies investigating HTC in East and Southern Africa from 2003 –April 2014. The search and additional snowballing identified 20 studies that fit our selection criteria. These studies were synthesised through a thematic framework analysis. Results Twenty qualitative and mixed-methods studies examining impacts of HTC models in East and Southern Africa were meta-synthesised. VCT decisions were made individually while HBVCT decisions were located in family and community units. PITC was associated with coercion from healthcare providers. Low quality counselling components and multiple-intersecting barriers faced by individuals mean that counselling in HTC was not perceived to be effective in reducing post-test risk behaviour and had limited perceived effect in facilitating linkage to care. Conclusion HBVCT is associated with minimal stigma and should be considered as an area of priority. Counselling components in HTC interventions were effective in transmitting information about HIV and sexual risk, but were perceived as ineffective in addressing the broader personal circumstances preventing sexual behaviour change and modulating access to care. PMID:28207802

Industrial symbiosis: corn ethanol fermentation, hydrothermal carbonization, and anaerobic digestion.

PubMed

Wood, Brandon M; Jader, Lindsey R; Schendel, Frederick J; Hahn, Nicholas J; Valentas, Kenneth J; McNamara, Patrick J; Novak, Paige M; Heilmann, Steven M

2013-10-01

The production of dry-grind corn ethanol results in the generation of intermediate products, thin and whole stillage, which require energy-intensive downstream processing for conversion into commercial animal feed products. Hydrothermal carbonization of thin and whole stillage coupled with anaerobic digestion was investigated as alternative processing methods that could benefit the industry. By substantially eliminating evaporation of water, reductions in downstream energy consumption from 65% to 73% were achieved while generating hydrochar, fatty acids, treated process water, and biogas co-products providing new opportunities for the industry. Processing whole stillage in this manner produced the four co-products, eliminated centrifugation and evaporation, and substantially reduced drying. With thin stillage, all four co-products were again produced, as well as a high quality animal feed. Anaerobic digestion of the aqueous product stream from the hydrothermal carbonization of thin stillage reduced chemical oxygen demand (COD) by more than 90% and converted 83% of the initial COD to methane. Internal use of this biogas could entirely fuel the HTC process and reduce overall natural gas usage. Copyright © 2013 Wiley Periodicals, Inc.

Using liquid waste streams as the moisture source during the hydrothermal carbonization of municipal solid wastes.

PubMed

Li, Liang; Hale, McKenzie; Olsen, Petra; Berge, Nicole D

2014-11-01

Hydrothermal carbonization (HTC) is a thermal conversion process that can be an environmentally beneficial approach for the conversion of municipal solid wastes to value-added products. The influence of using activated sludge and landfill leachate as initial moisture sources during the carbonization of paper, food waste and yard waste over time at 250°C was evaluated. Results from batch experiments indicate that the use of activated sludge and landfill leachate are acceptable alternative supplemental liquid sources, ultimately imparting minimal impact on carbonization product characteristics and yields. Regression results indicate that the initial carbon content of the feedstock is more influential than any of the characteristics of the initial liquid source and is statistically significant when describing the relationship associated with all evaluated carbonization products. Initial liquid-phase characteristics are only statistically significant when describing the solids energy content and the mass of carbon in the gas-phase. The use of these alternative liquid sources has the potential to greatly increase the sustainability of the carbonization process. A life cycle assessment is required to quantify the benefits associated with using these alternative liquid sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

Economical and green synthesis of bagasse-derived fluorescent carbon dots for biomedical applications.

PubMed

Du, Fengyi; Zhang, Miaomiao; Li, Xiaofeng; Li, Jianan; Jiang, Xinyi; Li, Zhang; Hua, Ye; Shao, Genbao; Jin, Jie; Shao, Qixiang; Zhou, Ming; Gong, Aihua

2014-08-08

Carbon quantum dots (CDs) are promising nanomaterials in biomedical, photocatalytical and photoelectronic applications. However, determining how to explore an ideal precursor for a renewable carbon resource is still an interesting challenge. Here, for the first time, we report that renewable wastes of bagasse as a new precursor were prepared for fluorescent CDs by a hydrothermal carbonization (HTC) process. The characterization results show that such bagasse-derived CDs are monodispersed, contain quasi spherical particles with a diameter of about 1.8 nm and exhibit favorable photoluminescence properties, super-high photostability and good dispersibility in water. Most importantly, bagasse-derived CDs have good biocompatibility and can be easily and quickly internalized by living cancer cells; they can also be used for multicolour biolabeling and bioimaging in cancer cells. It is suggested that bagasse-derived CDs might have potential applications in biomedical and photoelectronic fields.

Sorption enhanced reaction process (SERP) for the production of hydrogen

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

Hufton, J.; Mayorga, S.; Gaffney, T.

1998-08-01

The novel Sorption Enhanced Reaction Process has the potential to decrease the cost of hydrogen production by steam methane reforming. Current effort for development of this technology has focused on adsorbent development, experimental process concept testing, and process development and design. A preferred CO{sub 2} adsorbent, K{sub 2}CO{sub 3} promoted hydrotalcite, satisfies all of the performance targets and it has been scaled up for process testing. A separate class of adsorbents has been identified which could potentially improve the performance of the H{sub 2}-SER process. Although this material exhibits improved CO{sub 2} adsorption capacity compared to the HTC adsorbent, itsmore » hydrothermal stability must be improved. Single-step process experiments (not cyclic) indicate that the H{sub 2}-SER reactor performance during the reaction step improves with decreasing pressure and increasing temperature and steam to methane ratio in the feed. Methane conversion in the H{sub 2}-SER reactor is higher than for a conventional catalyst-only reactor operated at similar temperature and pressure. The reactor effluent gas consists of 90+% H{sub 2}, balance CH{sub 4}, with only trace levels (< 50 ppm) of carbon oxides. A best-case process design (2.5 MMSCFD of 99.9+% H{sub 2}) based on the HTC adsorbent properties and a revised SER process cycle has been generated. Economic analysis of this design indicates the process has the potential to reduce the H{sub 2} product cost by 25--31% compared to conventional steam methane reforming.« less

78 FR 77490 - Certain Electronic Imaging Devices; Notice of Commission Determination To Review-in-Part a Final...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-23

... concluded that two of the accused HTC smartphones, i.e., the HTC Vivid and HTC Droid Incredible 4G LTE... claims of the '538 patent by the HTC Vivid and HTC Droid Incredible 4G LTE smartphones; (2) the technical...

Co-hydrothermal treatment of fallen leaves with iron sludge to prepare magnetic iron product and solid fuel.

PubMed

Gu, Lin; Li, Binglian; Wen, Haifeng; Zhang, Xin; Wang, Liang; Ye, Jianfeng

2018-06-01

The hydrothermal carbonization (HTC) was performed on Metasequoia Leaves (ML) in the presence of iron sludge, both of which were generated as solid residuals. The relations between sludge, char's properties and operating conditions were systemically investigated. Iron sludge primarily catalyzed the efficient formation of char with higher heating value (HHV) becoming 1.15-1.65 times of ML (18.21 MJ/kg) and was meanwhile reduced to magnetite. The hydrated Fe ions in octahedron crystals acted as nucleophiles facilitating the dehydration and decarboxylation reactions. The increased HHV is found strong temperature dependent while prolonging the residence time is more preferable for low organic acids generation. Thermogravimetric analysis confirmed the iron sludge enhanced conversion of volatile to fixed carbon. The as-prepared solid char showed better stability after catalytic HTC treatment, having ignition temperature increased from 253 to 426 °C as compared to the char prepared without iron sludge addition. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hydrothermal conversion of xylose, glucose, and cellulose under the catalysis of transition metal sulfates.

PubMed

Cao, Xuefei; Peng, Xinwen; Sun, Shaoni; Zhong, Linxin; Chen, Wei; Wang, Sha; Sun, Run-Cang

2015-03-15

Hydrothermal conversion (HTC) is an important thermochemical process to upgrade low-cost biomass into valuable chemicals or fuels. As compared with non-catalytic HTC, catalytic HTC shows high energy efficiency on biomass upgradation. In this work, the catalytic performances of various transition metal sulfates (Mn(2+), Fe(2+), Fe(3+), Co(2+), Ni(2+), Cu(2+), and Zn(2+)) in the HTCs of xylose, glucose, and cellulose under different conditions were explored. Among these catalysts, Zn(2+) and Ni(2+) showed obvious effects on the conversions of xylose, glucose, and cellulose into lactic acid, while Cu(2+) and Fe(3+), which could significantly accelerate the hydrolysis of cellulose into glucose at 200°C, displayed high efficiency on converting glucose and cellulose into levulinic acid and formic acid at high temperature. Additionally, significant positive correlative relationships among xylose, glucose, and cellulose degradations were observed. This study is helpful for screening appropriate catalysts for biomass upgradation through catalytic HTC of monosaccharide. Copyright © 2014 Elsevier Ltd. All rights reserved.

Waste Water for Power Generation via Energy Efficient Selective Silica Separations

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

Nenoff, Tina M.; Brady, Patrick Vane; Sasan, Koroush

Silica is ubiquitous in produced and industrial waters, and plays a major disruptive role in water recycle. Herein we have investigated the use of mixed oxides for the removal of silica from these waters, and their incorporation into a low cost and low energy water purification process. High selectivity hydrotalcite (HTC, (Mg 6Al 2(OH) 16(CO 3)•4H 2O)), is combined in series with high surface area active alumina (AA, (Al 2O 3)) as the dissolved silica removal media. Batch test results indicated that combined HTC/AA is a more effective method for removing silica from industrial cooling tower wasters (CTW) than usingmore » HTC or AA separately. The silica uptake via ion exchange on the mixed oxides was confirmed by Fourier transform infrared (FTIR), and Energy dispersive spectroscopy (EDS). Furthermore, HTC/AA effectively removes silica from CTW even in the presence of large concentrations of competing anions, such as Cl -, NO 3 - HCO 3 -, CO 3 2- and SO 4 2-. Similar to batch tests, Single Path Flow Through (SPFT) tests with sequential HTC/AA column filtration has very high silica removal too. Technoeconomic Analysis (TEA) was simultaneously performed for cost comparisons to existing silica removal technologies.« less

Effect of pyrochar and hydrochar amendments on the mineralization of the herbicide isoproturon in an agricultural soil.

PubMed

Eibisch, Nina; Schroll, Reiner; Fuß, Roland

2015-09-01

Carbon (C)-rich, solid products from pyrolysis (pyrochars) and hydrothermal carbonization (HTC, hydrochars) are expected to reduce the bioavailability and bioaccessibility of pesticides as side effect of soil addition. To compare effects of different feedstocks (digestate, miscanthus, woodchips) and production processes (pyrolysis at 750°C, HTC at 200°C and 250°C), (14)C-labeled isoproturon (IPU) was applied at 0.75 kg ha(-)(1) to loamy sand amended either with 0.5% or 5% pyrochars or hydrochars, which was then incubated for 50d. Mineralization of IPU was measured as (14)C-CO2 released from soil-char composites. Pore-water and methanol extractable (14)C-IPU was quantified as well as non-extractable (14)C-residues (NER). Furthermore, C mineralization of pyrochars, hydrochars and feedstocks was studied to assess the relationship between IPU bioaccessibility and char decomposability. In pure soil, 8.1% of applied IPU was mineralized after 50d. This was reduced more strongly in pyrochar treatments (81 ± 6% reduction) than in hydrochar treatments (56 ± 25% reduction). Different feedstocks had no significantly different effect when 5% char was added, but their effect was significant and dependent on the production process in 0.5% amendments. Pesticide binding can occur by surface sorption as well as by diffusion and subsequent occlusion in micropores. The latter can be expected to result in high amounts of NER, as it was observed in the pyrochar treatments. Hydrochars were less stable than pyrochars and contained lower amounts of NER. Thus, in hydrochar amended soils, better accessibility of IPU to microbial degradation may be a result of full char decomposition within decades ensuring controlled pesticide degradation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Towards Universal Voluntary HIV Testing and Counselling: A Systematic Review and Meta-Analysis of Community-Based Approaches

PubMed Central

Suthar, Amitabh B.; Ford, Nathan; Bachanas, Pamela J.; Wong, Vincent J.; Rajan, Jay S.; Saltzman, Alex K.; Ajose, Olawale; Fakoya, Ade O.; Granich, Reuben M.; Negussie, Eyerusalem K.; Baggaley, Rachel C.

2013-01-01

Background Effective national and global HIV responses require a significant expansion of HIV testing and counselling (HTC) to expand access to prevention and care. Facility-based HTC, while essential, is unlikely to meet national and global targets on its own. This article systematically reviews the evidence for community-based HTC. Methods and Findings PubMed was searched on 4 March 2013, clinical trial registries were searched on 3 September 2012, and Embase and the World Health Organization Global Index Medicus were searched on 10 April 2012 for studies including community-based HTC (i.e., HTC outside of health facilities). Randomised controlled trials, and observational studies were eligible if they included a community-based testing approach and reported one or more of the following outcomes: uptake, proportion receiving their first HIV test, CD4 value at diagnosis, linkage to care, HIV positivity rate, HTC coverage, HIV incidence, or cost per person tested (outcomes are defined fully in the text). The following community-based HTC approaches were reviewed: (1) door-to-door testing (systematically offering HTC to homes in a catchment area), (2) mobile testing for the general population (offering HTC via a mobile HTC service), (3) index testing (offering HTC to household members of people with HIV and persons who may have been exposed to HIV), (4) mobile testing for men who have sex with men, (5) mobile testing for people who inject drugs, (6) mobile testing for female sex workers, (7) mobile testing for adolescents, (8) self-testing, (9) workplace HTC, (10) church-based HTC, and (11) school-based HTC. The Newcastle-Ottawa Quality Assessment Scale and the Cochrane Collaboration's “risk of bias” tool were used to assess the risk of bias in studies with a comparator arm included in pooled estimates.  117 studies, including 864,651 participants completing HTC, met the inclusion criteria. The percentage of people offered community-based HTC who accepted HTC was as follows: index testing, 88% of 12,052 participants; self-testing, 87% of 1,839 participants; mobile testing, 87% of 79,475 participants; door-to-door testing, 80% of 555,267 participants; workplace testing, 67% of 62,406 participants; and school-based testing, 62% of 2,593 participants. Mobile HTC uptake among key populations (men who have sex with men, people who inject drugs, female sex workers, and adolescents) ranged from 9% to 100% (among 41,110 participants across studies), with heterogeneity related to how testing was offered. Community-based approaches increased HTC uptake (relative risk [RR] 10.65, 95% confidence interval [CI] 6.27–18.08), the proportion of first-time testers (RR 1.23, 95% CI 1.06–1.42), and the proportion of participants with CD4 counts above 350 cells/µl (RR 1.42, 95% CI 1.16–1.74), and obtained a lower positivity rate (RR 0.59, 95% CI 0.37–0.96), relative to facility-based approaches. 80% (95% CI 75%–85%) of 5,832 community-based HTC participants obtained a CD4 measurement following HIV diagnosis, and 73% (95% CI 61%–85%) of 527 community-based HTC participants initiated antiretroviral therapy following a CD4 measurement indicating eligibility. The data on linking participants without HIV to prevention services were limited. In low- and middle-income countries, the cost per person tested ranged from US$2–US$126. At the population level, community-based HTC increased HTC coverage (RR 7.07, 95% CI 3.52–14.22) and reduced HIV incidence (RR 0.86, 95% CI 0.73–1.02), although the incidence reduction lacked statistical significance. No studies reported any harm arising as a result of having been tested. Conclusions Community-based HTC achieved high rates of HTC uptake, reached people with high CD4 counts, and linked people to care. It also obtained a lower HIV positivity rate relative to facility-based approaches. Further research is needed to further improve acceptability of community-based HTC for key populations. HIV programmes should offer community-based HTC linked to prevention and care, in addition to facility-based HTC, to support increased access to HIV prevention, care, and treatment. Review Registration International Prospective Register of Systematic Reviews CRD42012002554 Please see later in the article for the Editors' Summary PMID:23966838

What happens with the nitrogen in sewage sludge once this material is pyrolyzed?

NASA Astrophysics Data System (ADS)

Paneque, Marina; María De la Rosa, José; Kern, Jürgen; Knicker, Heike

2017-04-01

The transformation of sewage sludge (SS) into char by pyrolysis achieves sludge hygienization, a necessary step prior to a possible application on agricultural soils. Former studies indicated that during this process part of the organic nitrogen (No) of this material is incorporated into the aromatic network of the charred product and forms the so called black N (BN). De la Rosa and Knicker (2011) showed further that at least some of the BN is bioavailable. However, neither the pathways of BN formation nor its chemical structure is well understood. Therefore, we studied the production of inorganic N (Ni) and the forms of No after subjecting two types of SS to hydrothermal carbonization (HTC) and dry pyrolysis (Dry-Py). The samples were collected at two different stages of the wastewater treatment (hereafter A_SS and T_SS) at the Experimental Wastewater Treatment plant CENTA, located in Carrion de los Céspedes (Southern Spain). Four chars were produced by HTC at 200°C and 260°C, and with residence times of 30 min and 3 hours. Dry pyrolysis char was obtained after heating at 600°C for 1 hour. The organic N forms were revealed by solid-state 15N nuclear magnetic resonance (NMR) spectroscopy. All pyrolysis conditions resulted in a decrease of the amount of total N (Nt). Whereas HTC preserved between 83-59% of original N, only 2% were recovered in the char after Dry-Py. With respect to Ni, the amounts of ammonium and nitrite increased between 2 and 4 times compared to the non-treated SS after HTC. After Dry-Py no Ni was detected in the solid residue. The solid-state 15N NMR spectra of the non-treated SS are dominated by the signals assignable to amide-N. With increasing temperature and residence time applied during HTC, a shift of the signal intensity toward the region of pyrrole-N was evidenced. The largest contribution of pyrrole-N was identified in the sample obtained after heating at 260°C for 3h although the 15N-intensity in the chemical shift region of amide/carbazole N dominated the spectrum. In contrast, Dry-Py resulted in a dominance of pyrrole-N. In conclusion, our study demonstrated the impact of the pyrolysis conditions on the quantity and quality of N-forms in chars of SS. Considering the N fertilization potential, HTC chars may be more suitable than chars produced by Dry-Py if fast fertilization is needed due to the presence of Ni. On the other hand, the binding of N in heterocyclic structures retards its bioavailability. Thus Dry-Py chars will be a better choise, if slow N-release is wanted. However, deeper and specific researchers are necessary to confirm this hypothesis. De la Rosa JM, Knicker H (2011) Bioavailability of N released from N-rich pyrogenic organic matter: An incubation study. Soil Biology and Biogeochemistry 43: 2368-2373

76 FR 75910 - Certain Electronic Imaging Devices; Commission Determination To Affirm Finding of No Violation...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-05

... Section 337 by HTC. Specifically, the ALJ found that the accused HTC Android smartphones and the accused... the accused HTC Android smartphones, (2) infringement of the asserted claims of the '769 patent by the... with respect to the '769 patent on the bases that (1) the accused HTC Android smartphones and the...

Chemical, structural and combustion characteristics of carbonaceous products obtained by hydrothermal carbonization of palm empty fruit bunches.

PubMed

Parshetti, Ganesh K; Kent Hoekman, S; Balasubramanian, Rajasekhar

2013-05-01

A carbon-rich solid product, denoted as hydrochar, was synthesized by hydrothermal carbonization (HTC) of palm oil empty fruit bunch (EFB), at different pre-treatment temperatures of 150, 250 and 350 °C. The conversion of the raw biomass to its hydrochar occurred via dehydration and decarboxylation processes. The hydrochar produced at 350 °C had the maximum energy-density (>27 MJ kg(-1)) with 68.52% of raw EFB energy retained in the char. To gain a detailed insight into the chemical and structural properties, carbonaceous hydrochar materials were characterized by FE-SEM, FT-IR, XRD and Brunauer-Emmett-Teller (BET) analyses. This work also investigated the influence of hydrothermally treated hydrochars on the co-combustion characteristics of low rank Indonesian coal. Conventional thermal gravimetric analysis (TGA) parameters, kinetics and activation energy of different hydrochar and coal blends were estimated. Our results show that solid hydrochars improve the combustion of low rank coals for energy generation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Challenges in the delivery of public HIV testing and counselling (HTC) in Douala, Cameroon: providers perspectives and implications on quality of HTC services.

PubMed

Ngangue, Patrice; Gagnon, Marie-Pierre; Bedard, Emmanuelle

2017-04-08

The Cameroon government has made HIV testing and counselling (HTC) a priority in its HIV/AIDS strategic plan. However, there is a dearth of literature on the perspectives of providers on the quality of HTC services. The aim of this study was to explore challenges in the provision of HTC services and their implications on quality of HTC services in Douala's district hospitals. Two primary data collection methods supported by the Donabedian's model of healthcare were used to explain the challenges in the provision of HTC services and their implications on quality of HTC services. This consisted of semi-structured individual interviews with 6 nurses and 16 lay counsellors and a non-participant observation of the physical environment for HTC by site. The study sites were the prevention and voluntary testing and counselling centre (PVTCC) of the six district hospitals of the city of Douala. The study reveals concerns about confidentiality and privacy during the counselling sessions due to inadequate and limited space. An absence of consent, even verbal, was reported in one PVTCC. There is no specific accredited training curriculum that leads to a formal registration as a PVTCC staff, and some lay counsellors work without training. Lay counsellors carry the burden of HIV counselling, but the majority of them work for many years without remuneration and recognition. Another quality challenge is the high workload in the district hospitals' lab, which leads to long waiting times for HIV test results, thus contributing to failure to return for results. The findings of this study highlighted some issues such as lack of adequate space and equipment for HIV testing and counselling that hinder the quality of HTC services and should challenge the health authorities of Cameroon on the need to reorganize HTC services and create a national HIV quality assurance program.

The Impact of Repeat HIV Testing on Risky Sexual Behavior: Evidence from a Randomized Controlled Trial in Malawi

PubMed Central

Delavande, Adeline; Wagner, Zachary; Sood, Neeraj

2016-01-01

A significant proportion of HIV-positive adults in sub-Saharan Africa are in serodiscordant relationships. Identification of such serodiscordant couples through couple HIV testing and counseling (HTC) is thought to promote safe sexual behavior and reduce the probability of within couple seroconversion. However, it is possible HTC benefits are not sustained over time and therefore repeated HTC may be more effective at preventing seroconversion than one time HTC. We tested this theory in Zomba, Malawi by randomly assigning 170 serodiscordant couples to receive repeated HTC and 167 serodiscordant couples to receive one time HTC upon study enrollment (control group). We used linear probability models and probit model with couple fixed effects to assess the impact of the intervention on risky sexual behavior. At one-year follow-up, we found that couples that received repeated HTC reported significantly more condom use. However, we found no difference in rate of seroconversion between groups, nor did we find differences in subjective expectations about seroconversion or false beliefs about HIV, two expected pathways of behavior change. We conclude that repeated HTC may promote safe sexual behavior, but this result should be interpreted with caution, as it is inconsistent with the result from biological and subjective outcomes. PMID:27158553

The Impact of Repeat HIV Testing on Risky Sexual Behavior: Evidence from a Randomized Controlled Trial in Malawi.

PubMed

Delavande, Adeline; Wagner, Zachary; Sood, Neeraj

2016-03-01

A significant proportion of HIV-positive adults in sub-Saharan Africa are in serodiscordant relationships. Identification of such serodiscordant couples through couple HIV testing and counseling (HTC) is thought to promote safe sexual behavior and reduce the probability of within couple seroconversion. However, it is possible HTC benefits are not sustained over time and therefore repeated HTC may be more effective at preventing seroconversion than one time HTC. We tested this theory in Zomba, Malawi by randomly assigning 170 serodiscordant couples to receive repeated HTC and 167 serodiscordant couples to receive one time HTC upon study enrollment (control group). We used linear probability models and probit model with couple fixed effects to assess the impact of the intervention on risky sexual behavior. At one-year follow-up, we found that couples that received repeated HTC reported significantly more condom use. However, we found no difference in rate of seroconversion between groups, nor did we find differences in subjective expectations about seroconversion or false beliefs about HIV, two expected pathways of behavior change. We conclude that repeated HTC may promote safe sexual behavior, but this result should be interpreted with caution, as it is inconsistent with the result from biological and subjective outcomes.

Nitrogen-Functionalized Hydrothermal Carbon Materials by Using Urotropine as the Nitrogen Precursor.

PubMed

Straten, Jan Willem; Schleker, Philipp; Krasowska, Małgorzata; Veroutis, Emmanouil; Granwehr, Josef; Auer, Alexander A; Hetaba, Walid; Becker, Sylvia; Schlögl, Robert; Heumann, Saskia

2018-03-25

Nitrogen-containing hydrothermal carbon (N-HTC) materials of spherical particle morphology were prepared by means of hydrothermal synthesis with glucose and urotropine as precursors. The molar ratio of glucose to urotropine has been varied to achieve a continuous increase in nitrogen content. By raising the ratio of urotropine to glucose, a maximal nitrogen fraction of about 19 wt % could be obtained. Decomposition products of both glucose and urotropine react with each other; this opens up a variety of possible reaction pathways. The pH has a pronounced effect on the reaction pathway of the corresponding reaction steps. For the first time, a comprehensive analytical investigation, comprising a multitude of analytical tools and instruments, of a series of nitrogen-containing HTC materials was applied. Functional groups and structural motifs identified were analyzed by means of FTIR spectroscopy, thermogravimetric MS, and solid-state NMR spectroscopy. Information on reaction mechanisms and structural details were obtained by electronic structure calculations that were compared with vibrational spectra of polyfuran or polypyrrole-like groups, which represent structural motifs occurring in the present samples. © 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Effects of gamma-irradiation on cotyledon cell separation and pectin solubilisation in hard-to-cook cowpeas.

PubMed

Jombo, Talknice Z; Minnaar, Amanda; Taylor, John Rn

2018-03-01

Cowpeas stored under high temperature and humidity develop the hard-to-cook defect (HTC). This defect greatly increases cooking times and energy costs. To better understand the mechanisms involved in the HTC defect development, the effects of gamma-irradiation on cotyledon cellular structure and pectin solubility in two cowpea cultivars with different susceptibility to HTC defect were investigated. Gamma-irradiation decreased cotyledon cell wall thickness, increased cell size, and intercellular spaces in both cowpea cultivars and reduced cooking time of the less HTC susceptible cultivar. However, it did not reverse the HTC defect in the susceptible cultivar. Gamma-irradiation also increased the levels of cold water- and hot water-soluble pectin. The irradiation effects were thus mainly due to hydrolysis of pectin fractions in the cell walls. However, chelator-soluble pectin (CSP) solubility was not affected. As the cell wall changes brought about by gamma-irradiation were associated with pectin solubilisation, this supports the phytate-phytase-pectin theory as a major cause of the HTC defect. However, the non-reversal of the defect in HTC susceptible cowpeas and the absence of an effect on CSP indicate that other mechanisms are involved in HTC defect development in cowpeas, possibly the formation of alkali-soluble, ester bonded pectins. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Analysis of hard-to-cook red and black common beans using Fourier transform infrared spectroscopy.

PubMed

Maurer, Giselle A; Ozen, Banu F; Mauer, Lisa J; Nielsen, S Suzanne

2004-03-24

Extracted fractions from black and red common beans (Phaseolus vulgaris) were studied using Fourier transform infrared spectroscopy (FT-IR). Beans were stored under three conditions: control at 4 degrees C; hard-to-cook (HTC) at 29 degrees C, 65% RH for 3.5 months; and refrigerated at 2 degrees C, 79% RH for 3.5 months after a HTC period (called HTC-refrigerated). Two fractions isolated from the beans, the soluble pectin fraction (SPF) and the water insoluble residue of the cell wall (WIRCW), were analyzed using diffuse reflectance (DRIFTS) FT-IR. The soaking water and cooking water from the beans were also studied using attenuated total reflectance (ATR) FT-IR. The DRIFTS FT-IR results from the SPF and WIRCW fractions were consistent with previously published data for Carioca beans showing that in general, more phenolic compounds were associated with the SPF of HTC beans than in the control beans. Results also showed that HTC-refrigerated beans had higher concentrations of phenolic compounds than control beans in the SPF. The ATR FT-IR results for soaking and cooking waters from the HTC-refrigerated and HTC beans had higher concentrations of absorbing compounds than the control beans, indicating that they lost more constituents to the water. Additionally, results indicate that the mechanism(s) for reversibility of the HTC defect could be different than the one(s) involved in the development of the defect.

Hydrogel tissue construct-based high-content compound screening.

PubMed

Lam, Vy; Wakatsuki, Tetsuro

2011-01-01

Current pharmaceutical compound screening systems rely on cell-based assays to identify therapeutic candidates and potential toxicities. However, cells grown on 2D substrata or in suspension do not exhibit the mechanical or physiological properties of cells in vivo. To address this limitation, the authors developed an in vitro, high-throughput, 3D hydrogel tissue construct (HTC)-based assay system to quantify cell and tissue mechanical properties and multiple parameters of physiology. HTC mechanics was quantified using an automated device, and physiological status was assessed using spectroscopy-based indicators that were read on microplate readers. To demonstrate the application of this system, the authors screened 4 test compounds--rotenone (ROT), cytochalasin D (CD), 2,4-dinitrophenol (DNP), and Rho kinase inhibitor (H-1152)--for their ability to modulate HTC contractility without affecting actin integrity, mitochondrial membrane potential (MMP), or viability. All 4 compounds dose-dependently reduced HTC contractility. However, ROT was toxic, DNP dissipated MMP, and CD reduced both intracellular F-actin and viability. H-1152 was found to be the best candidate compound since it reduced HTC contractility with minimal side effects. The authors propose that their HTC-based assay system can be used to screen for compounds that modulate HTC contractility and assess the underlying physiological mechanism(s) of compound activity and toxicity.

Methadone Maintenance Treatment Promotes Referral and Uptake of HIV Testing and Counselling Services amongst Drug Users and Their Partners

PubMed Central

Nguyen, Lan Phuong; Nguyen, Cuong Tat; Phan, Huong Thi Thu; Latkin, Carl A.

2016-01-01

Background Methadone maintenance treatment (MMT) reduces HIV risk behaviors and improves access to HIV-related services among drug users. In this study, we assessed the uptake and willingness of MMT patients to refer HIV testing and counseling (HTC) service to their sexual partners and relatives. Methods Health status, HIV-related risk behaviors, and HTC uptake and referrals of 1,016 MMT patients in Hanoi and Nam Dinh were investigated. Willingness to pay (WTP) for HTC was elicited using a contingent valuation technique. Interval and logistic regression models were employed to determine associated factors. Results Most of the patients (94.2%) had received HTC, 6.6 times on average. The proportion of respondents willing to refer their partners, their relatives and to be voluntary peer educators was 45.7%, 35.3%, and 33.3%, respectively. Attending MMT integrated with HTC was a facilitative factor for HTC uptake, greater WTP, and volunteering as peer educators. Older age, higher education and income, and HIV positive status were positively related to willingness to refer partners or relatives, while having health problems (mobility, usual care, pain/discomfort) was associated with lower likelihood of referring others or being a volunteer. Over 90% patients were willing to pay an average of US $17.9 for HTC service. Conclusion The results highlighted the potential role of MMT patients as referrers to HTC and voluntary peer educators. Integrating HIV testing with MMT services and applying users’ fee are potential strategies to mobilize resources and encourage HIV testing among MMT patients and their partners. PMID:27046029

Home-based HIV testing for men preferred over clinic-based testing by pregnant women and their male partners, a nested cross-sectional study.

PubMed

Osoti, Alfred Onyango; John-Stewart, Grace; Kiarie, James Njogu; Barbra, Richardson; Kinuthia, John; Krakowiak, Daisy; Farquhar, Carey

2015-07-30

Male partner HIV testing and counseling (HTC) is associated with enhanced uptake of prevention of mother-to-child HIV transmission (PMTCT), yet male HTC during pregnancy remains low. Identifying settings preferred by pregnant women and their male partners may improve male involvement in PMTCT. Participants in a randomized clinical trial (NCT01620073) to improve male partner HTC were interviewed to determine whether the preferred male partner HTC setting was the home, antenatal care (ANC) clinic or VCT center. In this nested cross sectional study, responses were evaluated at baseline and after 6 weeks. Differences between the two time points were compared using McNemar's test and correlates of preference were determined using logistic regression. Among 300 pregnant female participants, 54% preferred home over ANC clinic testing (34.0%) or VCT center (12.0%). Among 188 male partners, 68% preferred home-based HTC to antenatal clinic (19%) or VCT (13%). Men who desired more children and women who had less than secondary education or daily income < $2 USD were more likely to prefer home-based over other settings (p < 0.05 for all comparisons). At 6 weeks, the majority of male (81%) and female (65%) participants recommended home over alternative HTC venues. Adjusting for whether or not the partner was tested during follow-up did not significantly alter preferences. Pregnant women and their male partners preferred home-based compared to clinic or VCT-center based male partner HTC. Home-based HTC during pregnancy appears acceptable and may improve male testing and involvement in PMTCT.

Removal of Dissolved Silica using Calcinated Hydrotalcite in Real-life Applications.

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

Sasan, Koroush; Brady, Patrick Vane.; Krumhansl, James L.

Water shortages are a growing global problem. Reclamation of industrial and municipal wastewater will be necessary in order to mitigate water scarcity. However, many operational challenges, such as silica scaling, prevent large scale water reuse. Previously, our team at Sandia has demonstrated the use of selective ion exchange materials, such as calcinated hydrotalcite (HTC, (Mg 6 Al 2 (OH) 16 (CO 3 )*4H 2 O)), for the low cost removal of silica from synthetic cooling tower water. However, it is not currently know if calcinated HTC has similar capabilities in realistic applications. The purpose of this study was to investigatemore » the ability of calcinated HTC to remove silica from real cooling tower water. This was investigated under both batch and continuous conditions, and in the presence of competing ions. It was determined that calcinated HTC behaved similarly in real and synthetic cooling tower water; the HTC is highly selective for the silica even in the presence of competing cations. Therefore, the data concludes that calcinated HTC is a viable anti-scaling pretreatment for the reuse of industrial wastewaters.« less

Chlorophyll-Based Organic-Inorganic Heterojunction Solar Cells.

PubMed

Li, Yue; Zhao, Wenjie; Li, Mengzhen; Chen, Gang; Wang, Xiao-Feng; Fu, Xueqi; Kitao, Osamu; Tamiaki, Hitoshi; Sakai, Kotowa; Ikeuchi, Toshitaka; Sasaki, Shin-Ichi

2017-08-10

Solid-state chlorophyll solar cells (CSCs) employing a carboxylated chlorophyll derivative, methyl trans-3 2 -carboxypyropheophorbide a, as a light-harvesting dye sensitizer chlorophyll (DSC) deposited on mesoporous TiO 2 , on which four zinc hydroxylated chlorophyll derivatives were spin-coated for hole transporter chlorophylls (HTCs), are described. Key parameters, including the effective carrier mobility of the HTC films, as determined by the space charge-limited current method, and the frontier molecular orbitals of these DSCs and HTCs, as estimated from cyclic voltammetry and electronic absorption spectra, suggest that both charge separation and carrier transport are favorable. The power conversion efficiencies (PCEs) of the present CSCs with fluorine-doped tin oxide (FTO)/TiO 2 /DSC/HTCs/Ag were determined to follow the order of HTC-1>HTC-2>HTC-3>HTC-4, which coincided perfectly with the order of their hole mobilities. The maximum PCE achieved was 0.86 % with HTC-1. The photovoltaic devices studied herein with two types of chlorophyll derivatives as dye sensitizers and hole transporters provide a unique solution for the utilization of solar energy with a view to truly realizing "green energy". © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Impact of HIV testing and counseling (HTC) knowledge on HIV prevention practices among traditional birth attendants in Nigeria.

PubMed

Osuji, Alice; Pharr, Jennifer R; Nwokoro, Uche; Ike, Anulika; Ali, Christiana; Ejiro, Ogheneaga; Osuyali, John; Obiefune, Michael; Fiscella, Kevin; Ezeanolue, Echezona E

2015-02-10

Nigeria is second in the world for the number of people with HIV and has a high rate of mother-to-child transmission (MTCT). Over 60% of births in Nigeria occur outside of health care facilities, and because of this, Traditional Birth Attendants (TBAs) play a significant role in maternal and child health. It is important that TBAs be knowledgeable about HIV prevention. The purpose of this study was to determine the impact of HIV testing and counseling (HTC) knowledge on the HIV prevention practices among TBAs in Nigeria. Five hundred TBAs were surveyed. Chi-square and logistic regression were used to assess differences in HIV prevention practices between TBAs with and without HTC knowledge. TBAs with HTC knowledge are significantly more likely to engage in HIV prevention practices than TBAs without HTC. Prevention practices included: wearing gloves during delivery (p < 0.01), sterilization of delivery equipment (p < 0.01), participation in blood safety training (p < 0.01), and disposal of sharps (p < 0.01). As long as a high percent of births occur outside health care facilities in Nigeria, there will be a need for TBAs. Providing TBAs with HTC training increases HIV prevention practices and can be a key to improve maternal and child health.

Impact of HIV Testing and Counseling (HTC) Knowledge on HIV Prevention Practices Among Traditional Birth Attendants in Nigeria

PubMed Central

Osuji, Alice; Pharr, Jennifer R.; Nwokoro, Uche; Ike, Anulika; Ali, Christiana; Ejiro, Ogheneaga; Osuyali, John; Obiefune, Michael; Fiscella, Kevin; Ezeanolue, Echezona E.

2015-01-01

Nigeria is second in the world for the number of people with HIV and has a high rate of mother-to-child transmission (MTCT). Over 60% of births in Nigeria occur outside of health care facilities, and because of this, Traditional Birth Attendants (TBAs) play a significant role in maternal and child health. It is important that TBAs be knowledgeable about HIV prevention. The purpose of this study was to determine the impact of HIV testing and counseling (HTC) knowledge on the HIV prevention practices among TBAs in Nigeria. Five hundred TBAs were surveyed. Chi-square and logistic regression were used to assess differences in HIV prevention practices between TBAs with and without HTC knowledge. TBAs with HTC knowledge are significantly more likely to engage in HIV prevention practices than TBAs without HTC. Prevention practices included: wearing gloves during delivery (p < 0.01), sterilization of delivery equipment (p < 0.01), participation in blood safety training (p < 0.01), and disposal of sharps (p < 0.01). As long as a high percent of births occur outside health care facilities in Nigeria, there will be a need for TBAs. Providing TBAs with HTC training increases HIV prevention practices and can be a key to improve maternal and child health. PMID:25674783

Development and validation of an universal interface for compound-specific stable isotope analysis of chlorine (37Cl/35Cl) by GC-high-temperature conversion (HTC)-MS/IRMS.

PubMed

Renpenning, Julian; Hitzfeld, Kristina L; Gilevska, Tetyana; Nijenhuis, Ivonne; Gehre, Matthias; Richnow, Hans-Hermann

2015-03-03

A universal application of compound-specific isotope analysis of chlorine was thus far limited by the availability of suitable analysis techniques. In this study, gas chromatography in combination with a high-temperature conversion interface (GC-HTC), converting organic chlorine in the presence of H2 to gaseous HCl, was coupled to a dual-detection system, combining an ion trap mass spectrometer (MS) and isotope-ratio mass spectrometer (IRMS). The combination of the MS/IRMS detection enabled a detailed characterization, optimization, and online monitoring of the high-temperature conversion process via ion trap MS as well as a simultaneous chlorine isotope analysis by the IRMS. Using GC-HTC-MS/IRMS, chlorine isotope analysis at optimized conversion conditions resulted in very accurate isotope values (δ(37)Cl(SMOC)) for measured reference material with known isotope composition, including chlorinated ethylene, chloromethane, hexachlorocyclohexane, and trichloroacetic acids methyl ester. Respective detection limits were determined to be <15 nmol Cl on column with achieved precision of <0.3‰.

Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer-chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS).

PubMed

Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A; Schimmelmann, Arndt

2017-03-30

Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H 2 ) is responsible for non-quantitative H 2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer-Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems. The EA-Cr/HTC reactor was substantially modified for the conversion of halogen- and sulfur-bearing samples. The performance of the novel conversion setup for solid and liquid samples was monitored and optimized using a simultaneously operating dual-detection system of IRMS and ion trap MS. The method with several variants in the reactor, including the addition of manganese metal chips, was evaluated in three laboratories using EA-Cr/HTC-IRMS (on-line method) and compared with traditional uranium-reduction-based conversion combined with manual dual-inlet IRMS analysis (off-line method) in one laboratory. The modified EA-Cr/HTC reactor setup showed an overall H 2 -recovery of more than 96% for all halogen- and sulfur-bearing organic compounds. All results were successfully normalized via two-point calibration with VSMOW-SLAP reference waters. Precise and accurate hydrogen isotopic analysis was achieved for a variety of organics containing F-, Cl-, Br-, I-, and S-bearing heteroelements. The robust nature of the on-line EA-Cr/HTC technique was demonstrated by a series of 196 consecutive measurements with a single reactor filling. The optimized EA-Cr/HTC reactor design can be implemented in existing analytical equipment using commercially available material and is universally applicable for both heteroelement-bearing and heteroelement-free organic-compound classes. The sensitivity and simplicity of the on-line EA-Cr/HTC-IRMS technique provide a much needed tool for routine hydrogen-isotope source tracing of organic contaminants in the environment. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Exceptional selectivity for dissolved silicas in industrial waters using mixed oxides

DOE PAGES

Sasan, Koroush; Brady, Patrick V.; Krumhansl, James L.; ...

2017-11-07

The removal of silica, ubiquitous in produced and industrial waters, by novel mixed oxides is investigated in this present study. We have combined the advantage of high selectivity hydrotalcite (HTC, (Mg 6Al 2(OH) 16(CO 3)·4H 2O)), with large surface area of active alumina (AA, (Al 2O 3)) for effective removing of the dissolved silica from cooling tower water. The batch test results indicated the combined HTC/AA is a more effective method for removing silica from CTW than using each of HTC or AA separately. The silica uptake was confirmed by Fourier transform infrared (FTIR), and Energy dispersive spectroscopy (EDS). Ourmore » results indicate HTC/AA effectively removes silica from cooling tower water (CTW), even in the presence of large concentrations of competing anions, such as Cl -, NO 3 - HCO 3 -, CO 3 2- and SO 4 2-. The Single Path Flow Through (SPFT) tests confirmed to rapid uptake of silica by combined HTC/AA during column filtration. The experimental data of silica adsorption fit best to Freundlich isotherm model.« less

Exceptional selectivity for dissolved silicas in industrial waters using mixed oxides

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

Sasan, Koroush; Brady, Patrick V.; Krumhansl, James L.

The removal of silica, ubiquitous in produced and industrial waters, by novel mixed oxides is investigated in this present study. We have combined the advantage of high selectivity hydrotalcite (HTC, (Mg 6Al 2(OH) 16(CO 3)·4H 2O)), with large surface area of active alumina (AA, (Al 2O 3)) for effective removing of the dissolved silica from cooling tower water. The batch test results indicated the combined HTC/AA is a more effective method for removing silica from CTW than using each of HTC or AA separately. The silica uptake was confirmed by Fourier transform infrared (FTIR), and Energy dispersive spectroscopy (EDS). Ourmore » results indicate HTC/AA effectively removes silica from cooling tower water (CTW), even in the presence of large concentrations of competing anions, such as Cl -, NO 3 - HCO 3 -, CO 3 2- and SO 4 2-. The Single Path Flow Through (SPFT) tests confirmed to rapid uptake of silica by combined HTC/AA during column filtration. The experimental data of silica adsorption fit best to Freundlich isotherm model.« less

Client characteristics and gender-specific correlates of testing HIV positive: a comparison of standalone center versus mobile outreach HIV testing and counseling in Botswana.

PubMed

Hood, Julia E; MacKellar, Duncan; Spaulding, Anne; Nelson, Rob; Mosiakgabo, Boingotlo; Sikwa, Bangwato; Puso, Innocentia; Raats, Jan; Loeto, Peter; Alwano, Mary Grace; Monyatsi, Blessed

2012-10-01

Using data from Botswana's largest HIV testing and counseling (HTC) provider, Tebelopele, we evaluate populations served and gender-specific correlates of testing HIV-positive among clients of two programs: standalone centers and outreach testing. Client records from January to June 2007 (n = 47,890) were evaluated by HTC program and gender. Bivariate and multivariate analyses were performed to identify demographic, testing, and risk-behavior variables associated with testing HIV-positive. Compared to outreach testing, standalone centers served proportionally more clients who were young, well-educated, unmarried, and HIV-infected; outreach testing reached an older, less-educated population. Age, educational attainment, marital status, couples testing, testing because of illness or discordant relationship, and nonuse of condoms (among young clients only) were consistently associated with testing HIV-positive, by HTC program and gender. Our evaluation suggests that Tebelopele standalone and outreach HTC programs serve different populations, and identifies strategies to reduce HIV infection risk and to improve uptake of HTC by HIV-infected, undiagnosed Batswana.

Extraction of drainage networks from large terrain datasets using high throughput computing

NASA Astrophysics Data System (ADS)

Gong, Jianya; Xie, Jibo

2009-02-01

Advanced digital photogrammetry and remote sensing technology produces large terrain datasets (LTD). How to process and use these LTD has become a big challenge for GIS users. Extracting drainage networks, which are basic for hydrological applications, from LTD is one of the typical applications of digital terrain analysis (DTA) in geographical information applications. Existing serial drainage algorithms cannot deal with large data volumes in a timely fashion, and few GIS platforms can process LTD beyond the GB size. High throughput computing (HTC), a distributed parallel computing mode, is proposed to improve the efficiency of drainage networks extraction from LTD. Drainage network extraction using HTC involves two key issues: (1) how to decompose the large DEM datasets into independent computing units and (2) how to merge the separate outputs into a final result. A new decomposition method is presented in which the large datasets are partitioned into independent computing units using natural watershed boundaries instead of using regular 1-dimensional (strip-wise) and 2-dimensional (block-wise) decomposition. Because the distribution of drainage networks is strongly related to watershed boundaries, the new decomposition method is more effective and natural. The method to extract natural watershed boundaries was improved by using multi-scale DEMs instead of single-scale DEMs. A HTC environment is employed to test the proposed methods with real datasets.

Partial Oxidation of Hydrocarbons in a Segmented Bed Using Oxide-based Catalysts and Oxygen-conducting Supports

NASA Astrophysics Data System (ADS)

Smith, Mark W.

Two objectives for the catalytic reforming of hydrocarbons to produce synthesis gas are investigated herein: (1) the effect of oxygen-conducting supports with partially substituted mixed-metal oxide catalysts, and (2) a segmented bed approach using different catalyst configurations. Excess carbon deposition was the primary cause of catalyst deactivation, and was the focus of the experiments for both objectives. The formation and characterization of deposited carbon was examined after reaction for one of the selected catalysts to determine the quantity and location of the carbon on the catalyst surface leading to deactivation. A nickel-substituted barium hexaaluminate (BNHA), with the formula BaAl 11.6Ni0.4O18.8, and a Rh-substituted lanthanum zirconate pyrochlore (LCZR) with the formula La1.89Ca0.11 Zr1.89Rh0.11, were combined with two different doped ceria supports. These supports were gadolinium-doped ceria (GDC) and zirconium-doped ceria (ZDC). The active catalyst phases were combined with the supports in different ratios using different synthesis techniques. The catalysts were characterized using several different techniques and were tested under partial oxidation (POX) of n-tetradecane (TD), a diesel fuel surrogate. It was found that the presence of GDC and ZDC reduced the formation of carbon for both catalysts; the optimal ratio of catalyst to support was different for the hexaaluminate and the pyrochlore; a loading of 20 wt% of the pyrochlore with ZDC produced the most stable performance in the presence of common fuel contaminants (>50 h); and, the incipient wetness impregnation synthesis method of applying the active catalyst to the support produced more stable product yields than the catalyst prepared by a solid-state mixing technique. Different hexaaluminate and pyrochlore catalysts were used in different configurations in a segmented bed approach. The first strategy was to promote the indirect reforming mechanism by placing a combustion catalyst in the reactor inlet, followed by a reforming catalyst. This approach demonstrated that BNHA can be used in the reactor inlet to promote combustion with 1 wt% Rh-substituted pyrochlore in the reactor outlet, but the combustion catalyst should fill less than 50% of the reactor. The second approach placed specific catalysts in regions of the reactor that have conditions in which they are less likely to deactivate. This showed the most benefit in the use of a sulfur-tolerant noble metal catalyst in the reactor outlet. The carbon formation study was conducted on a 2 wt% Rh-substituted pyrochlore. POX of TD for various run times, followed by temperature programmed oxidation, revealed two different types of carbon deposits in the catalyst bed: carbon that burned off at relatively low temperature (LTC), and carbon that burned off at higher temperatures (HTC). The LTC reached a steady state level within two hours of reaction, and was determined not to lead to catalyst deactivation. The HTC continued to accumulate with time on stream. A mathematical expression was developed to predict the rate of formation of the HTC for a given set of reaction conditions (O/C = 1.25). This expression was modified from data from a test under different reaction conditions (O/C = 1.1) for one length of time, and was found to predict the carbon formation for a different run time within 3%.

Isotopic disproportionation during hydrogen isotopic analysis of nitrogen-bearing organic compounds

USGS Publications Warehouse

Nair, Sreejesh; Geilmann, Heike; Coplen, Tyler B.; Qi, Haiping; Gehre, Matthias; Schimmelmann, Arndt; Brand, Willi A.

2015-01-01

Rationale High-precision hydrogen isotope ratio analysis of nitrogen-bearing organic materials using high-temperature conversion (HTC) techniques has proven troublesome in the past. Formation of reaction products other than molecular hydrogen (H2) has been suspected as a possible cause of incomplete H2 yield and hydrogen isotopic fractionation. Methods The classical HTC reactor setup and a modified version including elemental chromium, both operated at temperatures in excess of 1400 °C, have been compared using a selection of nitrogen-bearing organic compounds, including caffeine. A focus of the experiments was to avoid or suppress hydrogen cyanide (HCN) formation and to reach quantitative H2 yields. The technique also was optimized to provide acceptable sample throughput. Results The classical HTC reaction of a number of selected compounds exhibited H2 yields from 60 to 90 %. Yields close to 100 % were measured for the experiments with the chromium-enhanced reactor. The δ2H values also were substantially different between the two types of experiments. For the majority of the compounds studied, a highly significant relationship was observed between the amount of missing H2and the number of nitrogen atoms in the molecules, suggesting the pyrolytic formation of HCN as a byproduct. A similar linear relationship was found between the amount of missing H2 and the observed hydrogen isotopic result, reflecting isotopic fractionation. Conclusions The classical HTC technique to produce H2 from organic materials using high temperatures in the presence of glassy carbon is not suitable for nitrogen-bearing compounds. Adding chromium to the reaction zone improves the yield to 100 % in most cases. The initial formation of HCN is accompanied by a strong hydrogen isotope effect, with the observed hydrogen isotope results on H2 being substantially shifted to more negative δ2H values. The reaction can be understood as an initial disproportionation leading to H2 and HCN with the HCN-hydrogen systematically enriched in 2H by more than 50 ‰. In the reaction of HCN with chromium, H2 and chromium-containing solid residues are formed quantitatively.

Evaluation of the integrated hydrothermal carbonization-algal cultivation process for enhanced nitrogen utilization in Arthrospira platensis production.

PubMed

Yao, Changhong; Wu, Peichun; Pan, Yanfei; Lu, Hongbin; Chi, Lei; Meng, Yingying; Cao, Xupeng; Xue, Song; Yang, Xiaoyi

2016-09-01

Sustainable microalgal cultivation at commercial scale requires nitrogen recycling. This study applied hydrothermal carbonization to recover N of hot-water extracted Arthrospira platensis biomass residue into aqueous phase (AP) under different operation conditions and evaluated the N utilization, biomass yield and quality of A. platensis cultures using AP as the sole N source. With the increase of temperature at 190-210°C or reaction time of 2-3h, the N recovery rate decreased under nitrogen-repletion (+N) cultivation, while contrarily increased under nitrogen-limitation (-N) cultivation. Under +N biomass accumulation in the cultures with AP under 190°C was enhanced by 41-67% compared with that in NaNO3, and the highest protein content of 51.5%DW achieved under 200°C-2h was also 22% higher. Carbohydrate content of 71.4%DW under -N cultivation achieved under 210°C-3h was 14% higher than that in NaNO3. HTC-algal cultivation strategy under -N mode could save 60% of conventional N. Copyright © 2016 Elsevier Ltd. All rights reserved.

An Effect of Dexamethasone on Adenosine 3′,5′ -Monophosphate Content and Adenosine 3′,5′ -Monophosphate Phosphodiesterase Activity of Cultured Hepatoma Cells

PubMed Central

Manganiello, Vincent; Vaughan, Martha

1972-01-01

The effect of dexamethasone on adenosine 3′,5′-monophosphate (cAMP) phosphodiesterase activity in cultured HTC hepatoma cells was investigated. Homogenates of these cells contain phosphodiesterase activity with two apparent Michaelis constants for cAMP (2-5 μm and 50 μm). At all substrate concentrations tested, phosphodiesterase activity was decreased 25-40% in cells incubated for 36 hr or more with 1 μm dexamethasone. Acid phosphatase activity in the same cells was not decreased. α-Methyl testosterone, 1 μm, was without effect on phosphodiesterase activity. Incubation for 10 min with epinephrine plus theophylline increased the cAMP content of the HTC cells 3- to 6-fold. In cells incubated for 72 hr with dexamethasone, the basal concentration of cAMP was slightly increased and the increment produced by epinephrine plus theophylline was markedly increased. We believe that in many cells the so-called permissive effects of steroid hormones on cAMP mediated processes may be due to an effect of these hormones on cAMP phosphodiesterase activity similar to that observed in HTC cells incubated with dexamethasone. PMID:4341439

Correlation of heat transfer coefficient in quenching process using ABAQUS

NASA Astrophysics Data System (ADS)

Davare, Sandeep Kedarnath; Balachandran, G.; Singh, R. K. P.

2018-04-01

During the heat treatment by quenching in a liquid medium the convective heat transfer coefficient plays a crucial role in the extraction of heat. The heat extraction ultimately influences the cooling rate and hence the hardness and mechanical properties. A Finite Element analysis of quenching a simple flat copper sample with different orientation of sample and with different quenchant temperatures were carried out to check and verify the results obtained from the experiments. The heat transfer coefficient (HTC) was calculated from temperature history in a simple flat copper disc sample experimentally. This HTC data was further used as input to simulation software and the cooling curves were back calculated. The results obtained from software and using experimentation shows nearly consistent values.

BTEX biodegradation by bacteria from effluents of petroleum refinery.

PubMed

Mazzeo, Dânia Elisa Christofoletti; Levy, Carlos Emílio; de Angelis, Dejanira de Franceschi; Marin-Morales, Maria Aparecida

2010-09-15

Groundwater contamination with benzene, toluene, ethylbenzene and xylene (BTEX) has been increasing, thus requiring an urgent development of methodologies that are able to remove or minimize the damages these compounds can cause to the environment. The biodegradation process using microorganisms has been regarded as an efficient technology to treat places contaminated with hydrocarbons, since they are able to biotransform and/or biodegrade target pollutants. To prove the efficiency of this process, besides chemical analysis, the use of biological assessments has been indicated. This work identified and selected BTEX-biodegrading microorganisms present in effluents from petroleum refinery, and evaluated the efficiency of microorganism biodegradation process for reducing genotoxic and mutagenic BTEX damage through two test-systems: Allium cepa and hepatoma tissue culture (HTC) cells. Five different non-biodegraded BTEX concentrations were evaluated in relation to biodegraded concentrations. The biodegradation process was performed in a BOD Trak Apparatus (HACH) for 20 days, using microorganisms pre-selected through enrichment. Although the biodegradation usually occurs by a consortium of different microorganisms, the consortium in this study was composed exclusively of five bacteria species and the bacteria Pseudomonas putida was held responsible for the BTEX biodegradation. The chemical analyses showed that BTEX was reduced in the biodegraded concentrations. The results obtained with genotoxicity assays, carried out with both A. cepa and HTC cells, showed that the biodegradation process was able to decrease the genotoxic damages of BTEX. By mutagenic tests, we observed a decrease in damage only to the A. cepa organism. Although no decrease in mutagenicity was observed for HTC cells, no increase of this effect after the biodegradation process was observed either. The application of pre-selected bacteria in biodegradation processes can represent a reliable and effective tool in the treatment of water contaminated with BTEX mixture. Therefore, the raw petroleum refinery effluent might be a source of hydrocarbon-biodegrading microorganisms. Copyright 2010 Elsevier B.V. All rights reserved.

Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer–chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS)

USGS Publications Warehouse

Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B.; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A.; Schimmelmann, Arndt

2017-01-01

Conclusions: The optimized EA-Cr/HTC reactor design can be implemented in existing analytical equipment using commercially available material and is universally applicable for both heteroelement-bearing and heteroelement-free organic-compound classes. The sensitivity and simplicity of the on-line EA-Cr/HTC-IRMS technique provide a much needed tool for routine hydrogen-isotope source tracing of organic contaminants in the environment. Copyright © 2016 John Wiley & Sons, Ltd.

Prevalence of HIV testing and counseling and associated factors among secondary school students in Botswana.

PubMed

Bodika, Stephane M; Lekone, Phenyo E; Loeto, Peter; Alwano, Mary G; Zulu, Thekiso C; Kim, Evelyn; Machao, Gape; Voetsch, Andrew C

2016-05-01

The World Health Organization recommends HIV testing and counseling (HTC) for all adolescents living in countries with generalized HIV epidemics. In Botswana, HIV prevalence among adolescents 15-19 years is 3.7% and among pregnant adolescents is 10%. We describe the proportion and characteristics of secondary school students who have accessed HTC. A multistage sample survey was conducted among students in Botswana's public secondary schools in 2010. The survey was self-administered using a personal digital assistant device. The HTC rate was estimated using self-reported history of HIV testing. Of 1,632 participants, 52% were girls, 43% aged below 16 years, and 27% had ever had sexual intercourse. Most (81%) students knew where to get tested for HIV. Overall, 2.2% of students were HIV positive by self-report. The HTC rate was 23% overall, 34% among students who had ever had sexual intercourse, and 45% among students who had sexual intercourse in the past 12 months. Being pregnant or having made someone pregnant and having had sexual intercourse in the past 12 months were associated with having been tested for HIV among students who had ever had sexual intercourse. Overall, the HTC rate was low, and the self- reported HIV prevalence was high among secondary students in Botswana. Most sexually active students have never been tested for HIV. Health communications efforts for adolescents that increase demand for HTC, routine opt-out HIV testing in healthcare facilities, and school-based HIV testing are needed as part of a national HIV prevention strategy.

"Students want HIV testing in schools" a formative evaluation of the acceptability of HIV testing and counselling at schools in Gauteng and North West provinces in South Africa.

PubMed

Madiba, Sphiwe; Mokgatle, Mathilda

2015-04-17

The proposal by the South African Health Ministry to implement HIV testing and counselling (HTC) at schools in 2011 generated debates about the appropriateness of such testing. However, the debate has been between the Ministries of Education and Health, with little considerations of the students. The main aim of the study was to assess the students' opinions and uptake of HIV testing and counselling in general, and the acceptability of the provision of HIV testing and counselling in schools. The study also determined the association between socio-demographic characteristics, sexual behaviour, and HIV testing behaviour of the students. A survey was conducted among grade 10-12 high school students in North West and Gauteng provinces, South Africa. Seventeen high schools (nine rural and eight urban) were randomly selected for the administration of a researcher-assisted, self-administered, semi-structured questionnaire. A total of 2970 students aged 14-27 years participated in the study; 1632 (55%) were girls, 1810 (61%) ever had sex, and 1271 (49.8%) had more than one sex partner. The mean age of first sexual activity was 15.6. Half (n = 1494, 50.1%) had been tested for HIV. Having multiple sexual partners, age, and gender were significantly associated with increased odds of having had a HIV test. Fear, being un-informed about HTC, and low HIV risk perceptions were the reasons for not getting tested. The acceptability of HTC at school was high (n = 2282, 76.9%) and 2129 (71.8%) were willing to be tested at school. Appropriateness, privacy, and secrecy were the main arguments for and against HTC at school. One-third (n = 860, 29%) had intentions to disclose their HIV status to students versus 1258 (42.5%) for teachers. Stigma, discrimination and secrecy were the primary reasons students did not intend to disclose. A high acceptability of HTC and willingness to be tested at school suggest that HIV prevention programs tailored to youth have a high potential of success given the readiness of students to uptake HTC. Bringing HIV testing to the school setting will increase the uptake of HTC among youth and contribute towards efforts to scale up HTC in South Africa.

Uptake and linkage into care over one year of providing HIV testing and counselling through community and health facility testing modalities in urban informal settlement of Kibera, Nairobi Kenya.

PubMed

Muhula, Samuel; Memiah, Peter; Mbau, Lilian; Oruko, Happiness; Baker, Bebora; Ikiara, Geoffrey; Mungai, Margaret; Ndirangu, Meshack; Achwoka, Dunstan; Ilako, Festus

2016-05-04

We examine the uptake of HIV Testing and Counselling (HTC) and linkage into care over one year of providing HTC through community and health facility testing modalities among people living in Kibera informal urban settlement in Nairobi Kenya. We analyzed program data on health facility-based HIV testing and counselling and community- based testing and counselling approaches for the period starting October 2013 to September 2014. Univariate and bivariate analysis methods were used to compare the two approaches with regard to uptake of HTC and subsequent linkage to care. The exact Confidence Intervals (CI) to the proportions were approximated using simple normal approximation to binomial distribution method. Majority of the 18,591 clients were tested through health facility-based testing approaches 72.5 % (n = 13485) vs those tested through community-based testing comprised 27.5 % (n = 5106). More clients tested at health facilities were reached through Provider Initiated Testing and Counselling PITC 81.7 % (n = 11015) while 18.3 % were reached through Voluntary Counselling and Testing (VCT)/Client Initiated Testing and Counselling (CITC) services. All clients who tested positive during health facility-based testing were successfully linked to care either at the project sites or sites of client choice while not all who tested positive during community based testing were linked to care. The HIV prevalence among all those who were tested for HIV in the program was 5.2 % (n = 52, 95 % CI: 3.9 %-6.8 %). Key study limitation included use of aggregate data to report uptake of HTC through the two testing approaches and not being able to estimate the population in the catchment area likely to test for HIV. Health facility-based HTC approach achieved more clients tested for HIV, and this method also resulted in identifying greater numbers of people who were HIV positive in Kibera slum within one year period of testing for HIV compared to community-based HTC approach. Linking HIV positive clients to care proved much easier during health facility- based HTC compared to community- based HTC.

Implementation and Operational Research: Strengthening HIV Test Access and Treatment Uptake Study (Project STATUS): A Randomized Trial of HIV Testing and Counseling Interventions.

PubMed

McNaghten, A D; Schilsky Mneimneh, Allison; Farirai, Thato; Wamai, Nafuna; Ntiro, Marylad; Sabatier, Jennifer; Makhunga-Ramfolo, Nondumiso; Mwanasalli, Salli; Awor, Anna; Moore, Jan

2015-12-01

To determine which of 3 HIV testing and counseling (HTC) models in outpatient departments (OPDs) increases HIV testing and entry of newly identified HIV-infected patients into care. Randomized trial of HTC interventions. Thirty-six OPDs in South Africa, Tanzania, and Uganda were randomly assigned to 3 different HTC models: (A) health care providers referred eligible patients (aged 18-49, not tested in the past year, not known HIV positive) to on-site voluntary counseling and testing for HTC offered and provided by voluntary counseling and testing counselors after clinical consultation; (B) health care providers offered and provided HTC to eligible patients during clinical consultation; and (C) nurse or lay counselors offered and provided HTC to eligible patients before clinical consultation. Data were collected from October 2011 to September 2012. We describe testing eligibility and acceptance, HIV prevalence, and referral and entry into care. Chi-square analyses were conducted to examine differences by model. Of 79,910 patients, 45% were age eligible and 16,099 (45%) age eligibles were tested. Ten percent tested HIV positive. Significant differences were found in percent tested by model. The proportion of age eligible patients tested by Project STATUS was highest for model C (54.1%, 95% confidence interval [CI]: 42.4 to 65.9), followed by model A (41.7%, 95% CI: 30.7 to 52.8), and then model B (33.9%, 95% CI: 25.7 to 42.1). Of the 1596 newly identified HIV positive patients, 94% were referred to care (96.1% in model A, 94.7% in model B, and 94.9% in model C), and 58% entered on-site care (74.4% in model A, 54.8% in model B, and 55.6% in model C) with no significant differences in referrals or care entry by model. Model C resulted in the highest proportion of all age-eligible patients receiving a test. Although 94% of STATUS patients with a positive test result were referred to care, only 58% entered care. We found no differences in patients entering care by HTC model. Routine HTC in OPDs is acceptable to patients and effective for identifying HIV-infected persons, but additional efforts are needed to increase entry to care.

Experience and lessons from health impact assessment guiding prevention and control of HIV/AIDS in a copper mine project, northwestern Zambia.

PubMed

Knoblauch, Astrid M; Divall, Mark J; Owuor, Milka; Nduna, Kennedy; Ng'uni, Harrison; Musunka, Gertrude; Pascall, Anna; Utzinger, Jürg; Winkler, Mirko S

2017-07-04

To avoid or mitigate potential project-related adverse health effects, the Trident copper project in Kalumbila, northwestern Zambia, commissioned a health impact assessment. HIV was identified a priority health issue based on the local vulnerability to HIV transmission and experience from other mining projects in Africa. Hence, an HIV/AIDS management plan was developed, including community and workplace interventions, with HIV testing and counselling (HTC) being one of the key components. We present trends in HTC data over a 4-year period. In 13 communities affected by the Trident project, HTC was implemented from 2012 onwards, using rapid diagnostic tests, accompanied by pre- and post-test counselling through trained personnel. In addition, HTC was initiated in the project workforce in 2013, coinciding with the launch of the mine development. HTC uptake and HIV positivity rates were assessed in the study population and linked to demographic factors using regression analysis. In total, 11,638 community members and 5564 workers have taken up HTC with an increase over time. The HIV positivity rate in the community was 3.0% in 2012 and 3.4% in 2015, while positivity rate in the workforce was 5.2% in 2013 and 4.3% in 2015. Females showed a significantly higher odds of having a positive test result than males (odds ratio (OR) = 1.96, 95% confidence interval (CI): 1.55-2.50 among women in the community and OR = 2.90, 95% CI: 1.74-4.84 among women in the workforce). HTC users in the 35-49 years age group were most affected by HIV, with an average positivity rate of 6.6% in the community sample and 7.9% in the workforce sample. These study groups had 4.50 and 4.95 higher odds of being positive, respectively, compared to their younger counterparts (15-24 years). While HTC uptake increased five-fold in the community and almost three-fold in the workplace, the HIV positivity rates were insignificantly higher in 2015 compared to 2012. Our data can be used alongside other surveillance data to track HIV transmission in this specific context. Guided by the health impact assessment, the HIV prevention and control programme was readily adapted to the current setting through the identification of socioeconomic and environmental determinants of health.

Short Message Service (SMS) Command and Control (C2) Awareness in Android-based Smartphones Using Kernel-Level Auditing

DTIC Science & Technology

2012-06-14

Display 480 x 800 pixels (3.7 inches) CPU Qualcomm QSD8250 1GHz Memory (internal) 512MB RAM / 512 MB ROM Kernel version 2.6.35.7-ge0fb012 Figure 3.5: HTC...development and writing). The 34 MSM kernel provided by the AOSP and compatible with the HTC Nexus One’s motherboard and Qualcomm chipset, is used for this...building the kernel is having the prebuilt toolchains and the right kernel for the hardware. Many HTC products use Qualcomm processors which uses the

Hepatoma tissue culture (HTC) cells as a model for investigating the effects of low concentrations of herbicide on cell structure and function.

PubMed

Malatesta, M; Perdoni, F; Santin, G; Battistelli, S; Muller, S; Biggiogera, M

2008-12-01

Previous studies on mice fed genetically modified (GM) soybean demonstrated modifications of the mitochondrial functions and of the transcription/splicing pathways in hepatocytes. The cause(s) of these alterations could not be conclusively established but, since the GM soybean used is tolerant to glyphosate and was treated with the glyphosate-containing herbicide Roundup , the possibility exists that the effects observed may be due to herbicide residues. In order to verify this hypothesis, we treated HTC cells with 1-10mM Roundup and analysed cellular features by flow cytometry, fluorescence and electron microscopy. Under these experimental conditions, the death rate and the general morphology of HTC cells were not affected, as well as most of the cytoplasmic organelles. However, in HTC-treated cells, lysosome density increased and mitochondrial membranes modified indicating a decline in the respiratory activity. Moreover, nuclei underwent morpho-functional modifications suggestive of a decreased transcriptional/splicing activity. Although we cannot exclude that other factors than the presence of the herbicide residues could be responsible for the cellular modifications described in GM-fed mice, the concordance of the effects induced by low concentrations of Roundup on HTC cells suggests that the presence of Roundup residues could be one of the factors interfering with multiple metabolic pathways.

Comparison Of Eigenvector-Based Statistical Pattern Recognition Algorithms For Hybrid Processing

NASA Astrophysics Data System (ADS)

Tian, Q.; Fainman, Y.; Lee, Sing H.

1989-02-01

The pattern recognition algorithms based on eigenvector analysis (group 2) are theoretically and experimentally compared in this part of the paper. Group 2 consists of Foley-Sammon (F-S) transform, Hotelling trace criterion (HTC), Fukunaga-Koontz (F-K) transform, linear discriminant function (LDF) and generalized matched filter (GMF). It is shown that all eigenvector-based algorithms can be represented in a generalized eigenvector form. However, the calculations of the discriminant vectors are different for different algorithms. Summaries on how to calculate the discriminant functions for the F-S, HTC and F-K transforms are provided. Especially for the more practical, underdetermined case, where the number of training images is less than the number of pixels in each image, the calculations usually require the inversion of a large, singular, pixel correlation (or covariance) matrix. We suggest solving this problem by finding its pseudo-inverse, which requires inverting only the smaller, non-singular image correlation (or covariance) matrix plus multiplying several non-singular matrices. We also compare theoretically the effectiveness for classification with the discriminant functions from F-S, HTC and F-K with LDF and GMF, and between the linear-mapping-based algorithms and the eigenvector-based algorithms. Experimentally, we compare the eigenvector-based algorithms using a set of image data bases each image consisting of 64 x 64 pixels.

Co-gasification of bituminous coal and hydrochar derived from municipal solid waste: Reactivity and synergy.

PubMed

Wei, Juntao; Guo, Qinghua; He, Qing; Ding, Lu; Yoshikawa, Kunio; Yu, Guangsuo

2017-09-01

In this work, the influences of gasification temperature and blended ratio on co-gasification reactivity and synergy of Shenfu bituminous coal (SF) and municipal solid waste-derived hydrochar (HTC) were investigated using TGA. Additionally, active alkaline and alkaline earth metal (AAEM) transformation during co-gasification was quantitatively analyzed by inductively coupled plasma optical emission spectrometer for correlating synergy on co-gasification reactivity. The results showed that higher char gasification reactivity existed at higher HTC char proportion and gasification temperature, and the main synergy behaviour on co-gasification reactivity was performed as synergistic effect. Enhanced synergistic effect at lower temperature was mainly resulted from more obviously inhibiting the primary AAEM (i.e. active Ca) transformation, and weak synergistic effect still existed at higher temperature since more active K with prominent catalysis was retained. Furthermore, more active HTC-derived AAEM remaining in SF sample during co-gasification would lead to enhanced synergistic effect as HTC char proportion increased. Copyright © 2017 Elsevier Ltd. All rights reserved.

78 FR 32689 - Certain Portable Electronic Communications Devices, Including Mobile Phones and Components...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-31

..., Including Mobile Phones and Components Thereof Notice of Receipt of Complaint; Solicitation of Comments... Certain Portable Electronic Communications Devices, Including Mobile Phones and Components Thereof, DN... mobile phones and components thereof. The complaint names as respondents HTC Corporation of China and HTC...

Parents Support Implementation of HIV Testing and Counseling at School: Cross-Sectional Study with Parents of Adolescent Attending High School in Gauteng and North West Provinces, South Africa

PubMed Central

Mokgatle, Mathildah

2016-01-01

Background. A formative assessment of the implementation of HIV testing and counseling (HTC) at school showed high acceptability and willingness to test among learners. However, the success of the proposed HTC depends on the support and acceptability of key stakeholders, including the parents. The aim of the study was to assess the opinions and acceptability of the implementation of HTC at school among parents of adolescents in high school. Methods. This was a cross-sectional household survey conducted with parents of adolescents attending high schools in educational districts in North West and Gauteng provinces, South Africa. Results. A total of 804 parents participated, and 548 (68.3%) were biological mothers, 85 (10.6%) were fathers, and the remaining were other relatives including grandmothers. Almost all (n = 742, 92.9%) parents were in support of implementation and provision of HTC at school, 701 (87.7%) would allow their children to be tested at school, 365 (46%) felt that parental consent was not needed to test at school, and 39.4% preferred to receive the HIV test results with their children. Conclusion. Parents accept the roll-out of an HTC program at school and have a role to play in supporting children who test positive for HIV. PMID:27807481

From Industry to Teaching: The Quality Instruction Program at Hocking Technical College.

ERIC Educational Resources Information Center

Moran, Ralph; And Others

This presentation on Hocking Technical College's (HTC's) Quality Instruction Program (QIP) provides a program description and comments from three HTC faculty members who have been involved in the program in various ways. Recognizing that many faculty members are hired on the basis of their industrial credentials rather than their teaching…

76 FR 76759 - Certain Portable Communication Devices, Receipt of Complaint; Solicitation of Comments Relating...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-08

... Park, New Jersey; Samsung Telecommunications America, LLC of Richardson, TX; Sony Corporation of Japan; Sony Corporation of America of New York, NY; Sony Electronics, Inc. of San Diego, CA; Sony Ericsson...; Research In Motion Corp. of Irving, TX; HTC Corporation of Taiwan; HTC America, Inc. of Bellevue, WA; LG...

Experimental investigation of time and repeated cycles in nucleate pool boiling of alumina/water nanofluid on polished and machined surfaces

NASA Astrophysics Data System (ADS)

Rajabzadeh Dareh, F.; Haghshenasfard, M.; Nasr Esfahany, M.; Salimi Jazi, H.

2018-06-01

Pool boiling heat transfer of pure water and nanofluids on a copper block has been studied experimentally. Nanofluids with various concentrations of 0.0025, 0.005 and 0.01 vol.% are employed and two simple surfaces (polished and machined copper surface) are used as the heating surfaces. The results indicated that the critical heat flux (CHF) in boiling of fluids on the polished surface is 7% higher than CHF on the machined surface. In the case of machined surface, the heat transfer coefficient (HTC) of 0.01 vol.% nanofluid is about 37% higher than HTC of base fluid, while in the polished surface the average HTC of 0.01% nanofluid is about 19% lower than HTC of the pure water. The results also showed that the boiling time and boiling cycles on the polished surface changes the heat transfer performance. By increasing the boiling time from 5 to 10 min, the roughness enhances about 150%, but by increasing the boiling time to 15 min, the roughness enhancement is only 8%.

Influence of processing and storage of integral grape juice (Vitis labrusca L.) on its physical and chemical characteristics, cytotoxicity, and mutagenicity in vitro.

PubMed

Düsman, E; Almeida, I V; Pinto, E P; Lucchetta, L; Vicentini, V E P

2017-05-31

Integral grape juice is extracted from the grape through processes that allow the retention of their natural composition. However, due to the severity of some processes, fruit juices can undergo changes in their quality. The present study evaluated the cytotoxic and mutagenic effects of integral grape juice by a cytokinesis-blocked micronucleus assay in Rattus norvegicus hepatoma cells (HTC) in vitro. Vitis labrusca L. (variety Concord) were produced organically and by a conventional system, and their juice was extracted by a hot extraction process. The organic grapes were subjected to ultraviolet-type C radiation (UV-C). Experiments were performed after production and after 6 months in storage. Physicochemical analyses revealed that UV-C irradiation of organic grapes, the juice production process, and storage resulted in nutraceutical alterations. However, none of the juice concentrations were cytotoxic to HTC cells by the cytokinesis-blocked proliferation index results or were mutagenic, because the formation of micronucleated cells was not induced. In general, juice induced cell proliferation, possibly due to the presence of vitamins and sugar content (total soluble solid). The data increased the understanding of food technology and confirmed the quality and safety consumption of these juices.

Heat and ultraviolet light treatment of colostrum and hospital milk: effects on colostrum and hospital milk characteristics and calf health and growth parameters.

PubMed

Teixeira, A G V; Bicalho, M L S; Machado, V S; Oikonomou, G; Kacar, C; Foditsch, C; Young, R; Knauer, W A; Nydam, D V; Bicalho, R C

2013-08-01

The aim of this study was to evaluate the effects of different physical treatments of bovine colostrum and hospital milk on milk bacteriology, immunoglobulin G (IgG) and lactoferrin concentrations, calf serum IgG concentrations and calf health, growth and survivability. Pooled colostrum samples (n=297) were heat treated (HTC; 63°C for 60 min), exposed to ultraviolet light (UVC; 45 J/cm(2)) or untreated ('raw', RC). Hospital milk (n=712) was subjected to high temperature short time pasteurization (HTST; 72°C for 15s), ultraviolet light irradiation (UVH; 45 J/cm(2)) or was untreated. Neonatal Holstein heifer calves (n=875) were randomly enrolled (309 HTC, 285 UVC, 281 RC) and block randomized (by colostrum treatment) into hospital milk treatments HTST (n=449) or UVH (n=426). HTC was more effective than UVC and HTST was more effective than UVH in reducing bacterial counts. IgG and lactoferrin concentrations were significantly lower in HTC and UVC than in RC. Lactoferrin concentrations were significantly lower in HTST than in UVH or untreated hospital milk. There were no significant differences in serum IgG concentrations among calves fed HTC, UVC or RC. Colostrum and hospital milk treatments did not have any significant effect on calf body weight gain, survivability, or frequency of diarrhea or pneumonia. Copyright © 2013 Elsevier Ltd. All rights reserved.

An automatic eye detection and tracking technique for stereo video sequences

NASA Astrophysics Data System (ADS)

Paduru, Anirudh; Charalampidis, Dimitrios; Fouts, Brandon; Jovanovich, Kim

2009-05-01

Human-computer interfacing (HCI) describes a system or process with which two information processors, namely a human and a computer, attempt to exchange information. Computer-to-human (CtH) information transfer has been relatively effective through visual displays and sound devices. On the other hand, the human-tocomputer (HtC) interfacing avenue has yet to reach its full potential. For instance, the most common HtC communication means are the keyboard and mouse, which are already becoming a bottleneck in the effective transfer of information. The solution to the problem is the development of algorithms that allow the computer to understand human intentions based on their facial expressions, head motion patterns, and speech. In this work, we are investigating the feasibility of a stereo system to effectively determine the head position, including the head rotation angles, based on the detection of eye pupils.

77 FR 515 - Certain Portable Communication Devices; Receipt of Amended Complaint; Solicitation of Comments...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-05

... Telecommunications America, LLC of Richardson, TX; Sony Corporation of Japan; Sony Corporation of America of New York, NY; Sony Electronics, Inc. of San Diego, CA; Sony Ericsson Mobile Communication AB of Sweden; Sony... Corp. of Irving, TX; HTC Corporation of Taiwan; HTC America, Inc. of Bellevue, WA; LG Electronics, Inc...

77 FR 17094 - In the Matter of Certain Portable Communication Devices Commission Determination Not To Review an...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-23

... Richardson, Texas; Sony Corporation of Tokyo, Japan; Sony Corporation of America of New York, New York; Sony Electronics, Inc. of San Diego, California; Sony Ericsson Mobile Communications AB of Lund, Sweden; Sony...; Research In Motion Corp. of Irving, Texas; HTC Corporation of Taoyuan, Taiwan; HTC America, Inc. of...

Implementation of human thermal comfort information in Köppen-Geiger climate classification—the example of China

NASA Astrophysics Data System (ADS)

Yang, Shi-Qi; Matzarakis, Andreas

2016-11-01

Köppen-Geiger climate classification (KGC) is accepted and applied worldwide. The climatic parameters utilised in KGC, however, cannot indicate human thermal comfort (HTC) conditions or air humidity (AH) conditions directly, because they are originally based on climatic effects on vegetation, instead of that on human body directly. In addition, HTC is driven by meteorological parameters together. Thus, the objective of this study is to preliminarily implement the HTC information and the AH information in KGC. Physiologically equivalent temperature (PET) has been chosen as the HTC index, and vapour pressure (VP) is for the quantification of AH conditions. In this preliminary study, 12 Chinese cities in total have been taken into account as the assumed representatives of 11 climate types. Basic meteorological data of each city with 3-h resolution in 2000-2012 has been analysed. RayMan model has been applied to calculate PET within the same time period. Each climate type has been described by frequencies of PET and frequencies of VP. For example, the Aw (Sanya) has the most frequent occurrence of thermally stressful conditions compared to other climate types: PET in 22 % points in time of the year was above 35 °C. The driest AH conditions existed in Dwc (Lhasa) and Dfb (Urumqi) with VP rarely above 18 hPa in the wettest month. Implementation of the HTC information and the additional AH information in each climate type of KGC can be helpful for the topics of human health, energy consumption, tourism, as well as urban planning.

Implementation of human thermal comfort information in Köppen-Geiger climate classification-the example of China.

PubMed

Yang, Shi-Qi; Matzarakis, Andreas

2016-11-01

Köppen-Geiger climate classification (KGC) is accepted and applied worldwide. The climatic parameters utilised in KGC, however, cannot indicate human thermal comfort (HTC) conditions or air humidity (AH) conditions directly, because they are originally based on climatic effects on vegetation, instead of that on human body directly. In addition, HTC is driven by meteorological parameters together. Thus, the objective of this study is to preliminarily implement the HTC information and the AH information in KGC. Physiologically equivalent temperature (PET) has been chosen as the HTC index, and vapour pressure (VP) is for the quantification of AH conditions. In this preliminary study, 12 Chinese cities in total have been taken into account as the assumed representatives of 11 climate types. Basic meteorological data of each city with 3-h resolution in 2000-2012 has been analysed. RayMan model has been applied to calculate PET within the same time period. Each climate type has been described by frequencies of PET and frequencies of VP. For example, the Aw (Sanya) has the most frequent occurrence of thermally stressful conditions compared to other climate types: PET in 22 % points in time of the year was above 35 °C. The driest AH conditions existed in Dwc (Lhasa) and Dfb (Urumqi) with VP rarely above 18 hPa in the wettest month. Implementation of the HTC information and the additional AH information in each climate type of KGC can be helpful for the topics of human health, energy consumption, tourism, as well as urban planning.

Expanding HIV testing and counselling into communities: Feasibility, acceptability, and effects of an integrated family planning/HTC service delivery model by Village Health Teams in Uganda.

PubMed

Brunie, Aurélie; Wamala-Mucheri, Patricia; Akol, Angela; Mercer, Sarah; Chen, Mario

2016-10-01

Improving HIV testing and counselling (HTC) requires a range of strategies. This article reports on HTC service delivery by Village Health Teams (VHTs) in Uganda in the context of a model integrating this new component into pre-existing family planning services. Eight health centres from matched pairs were randomly allocated to intervention or control. After being trained, 36 VHTs reporting to selected facilities in the intervention group started offering HTC along with family planning, while VHTs in the control group provided family planning only. Proficiency testing was conducted as external quality assurance. A survey of all 36 VHTs and 137 family planning clients in the intervention group and 119 clients in the control group and a review of record data were conducted after 10 months. Survey responses by VHTs and their clients in the intervention group demonstrate knowledge of counselling messages and safe testing. External quality assessment results provide additional evidence of competency. Eighty per cent of the family planning clients surveyed in the intervention group received an HIV test during the intervention; 27% of those were first-time testers. More clients had ever tested for HIV in the intervention group compared with the control; clients also retested more often. Findings indicate that this model is feasible and acceptable for expanding quality HTC into communities. This study was registered with ClinicalTrials.gov, number [NCT02244398]. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Comparisons of different methods for virus-elimination of edible fungi].

PubMed

Zhang, Chao-hui; Liu, Ying-miao; Qi, Yuan-cheng; Gao, Yu-qian; Shen, Jin-wen; Qiu, Li-you

2010-05-01

Four dsRNA bands were extracted from Pleurotus ostreatus TD300 by the dsRNA isolation technique with sizes of 8.2 kb, 2.5 kb, 2.1 kb, and 1.1 kb, respectively. Four virus-eliminated methods, i. e. hyphal tips cut (HTC), protoplast regeneration (PR), single spore hybridization (SSH), and frozen and lyophilized (FL), were applied to prepare virus-eliminated strains, and one virus-eliminated strain was selected for each virus-elimination method. The virus-eliminated strains were named as HTC8, PR15, FL01, and SSH11, respectively. There were low concentration of 8.2 kb dsRNA remained in HTC8, as well as low concentration of 8.2 kb and 2.5 kb dsRNA remained in FL01. However, no dsRNA remained in PR15 and SSH11. The hyphal growth rate and laccase activity of the virus-eliminated strains increased, especially HTC8 and PR15, whose hyphal growth rate was higher by 22.73% and 18.18%, and laccase activities higher by 145.83% and 134.38% than that of the original strain, respectively. The conclusion is that hyphal tips cut and protoplast regeneration are suitable to prepare virus-eliminated strains of edible fungi.

Calculation and validation of heat transfer coefficient for warm forming operations

NASA Astrophysics Data System (ADS)

Omer, Kaab; Butcher, Clifford; Worswick, Michael

2017-10-01

In an effort to reduce the weight of their products, the automotive industry is exploring various hot forming and warm forming technologies. One critical aspect in these technologies is understanding and quantifying the heat transfer between the blank and the tooling. The purpose of the current study is twofold. First, an experimental procedure to obtain the heat transfer coefficient (HTC) as a function of pressure for the purposes of a metal forming simulation is devised. The experimental approach was used in conjunction with finite element models to obtain HTC values as a function of die pressure. The materials that were characterized were AA5182-O and AA7075-T6. Both the heating operation and warm forming deep draw were modelled using the LS-DYNA commercial finite element code. Temperature-time measurements were obtained from both applications. The results of the finite element model showed that the experimentally derived HTC values were able to predict the temperature-time history to within a 2% of the measured response. It is intended that the HTC values presented herein can be used in warm forming models in order to accurately capture the heat transfer characteristics of the operation.

Cost-Effective Additive Manufacturing in Space: HELIOS Technology Challenge Guide

NASA Technical Reports Server (NTRS)

DeVieneni, Alayna; Velez, Carlos Andres; Benjamin, David; Hollenbeck, Jay

2012-01-01

Welcome to the HELIOS Technology Challenge Guide. This document is intended to serve as a general road map for participants of the HELIOS Technology Challenge [HTC] Program and the associated inaugural challenge: HTC-01: Cost-Effective Additive Manufacturing in Space. Please note that this guide is not a rule book and is not meant to hinder the development of innovative ideas. Its primary goal is to highlight the objectives of the HTC-01 Challenge and to describe possible solution routes and pitfalls that such technology may encounter in space. Please also note that participants wishing to demonstrate any hardware developed under this program during any future HELIOS Technology Challenge showcase event(s) may be subject to event regulations to be published separately at a later date.

Cost-effectiveness of community-based strategies to strengthen the continuum of HIV care in rural South Africa: a health economic modelling analysis.

PubMed

Smith, Jennifer A; Sharma, Monisha; Levin, Carol; Baeten, Jared M; van Rooyen, Heidi; Celum, Connie; Hallett, Timothy B; Barnabas, Ruanne V

2015-04-01

Home HIV counselling and testing (HTC) achieves high coverage of testing and linkage to care compared with existing facility-based approaches, particularly among asymptomatic individuals. In a modelling analysis we aimed to assess the effect on population-level health and cost-effectiveness of a community-based package of home HTC in KwaZulu-Natal, South Africa. We parameterised an individual-based model with data from home HTC and linkage field studies that achieved high coverage (91%) and linkage to antiretroviral therapy (80%) in rural KwaZulu-Natal, South Africa. Costs were derived from a linked microcosting study. The model simulated 10,000 individuals over 10 years and incremental cost-effectiveness ratios were calculated for the intervention relative to the existing status quo of facility-based testing, with costs discounted at 3% annually. The model predicted implementation of home HTC in addition to current practice to decrease HIV-associated morbidity by 10–22% and HIV infections by 9–48% with increasing CD4 cell count thresholds for antiretroviral therapy initiation. Incremental programme costs were US$2·7 million to $4·4 million higher in the intervention scenarios than at baseline, and costs increased with higher CD4 cell count thresholds for antiretroviral therapy initiation; antiretroviral therapy accounted for 48–87% of total costs. Incremental cost-effectiveness ratios per disability-adjusted life-year averted were $1340 at an antiretroviral therapy threshold of CD4 count lower than 200 cells per μL, $1090 at lower than 350 cells per μL, $1150 at lower than 500 cells per μL, and $1360 at universal access to antiretroviral therapy. Community-based HTC with enhanced linkage to care can result in increased HIV testing coverage and treatment uptake, decreasing the population burden of HIV-associated morbidity and mortality. The incremental cost-effectiveness ratios are less than 20% of South Africa's gross domestic product per person, and are therefore classed as very cost effective. Home HTC can be a viable means to achieve UNAIDS' ambitious new targets for HIV treatment coverage. National Institutes of Health, Bill & Melinda Gates Foundation, Wellcome Trust.

Comparison of Oculus Rift and HTC Vive: Feasibility for Virtual Reality-Based Exploration, Navigation, Exergaming, and Rehabilitation.

PubMed

Borrego, Adrián; Latorre, Jorge; Alcañiz, Mariano; Llorens, Roberto

2018-06-01

The latest generation of head-mounted displays (HMDs) provides built-in head tracking, which enables estimating position in a room-size setting. This feature allows users to explore, navigate, and move within real-size virtual environments, such as kitchens, supermarket aisles, or streets. Previously, these actions were commonly facilitated by external peripherals and interaction metaphors. The objective of this study was to compare the Oculus Rift and the HTC Vive in terms of the working range of the head tracking and the working area, accuracy, and jitter in a room-size environment, and to determine their feasibility for serious games, rehabilitation, and health-related applications. The position of the HMDs was registered in a 10 × 10 grid covering an area of 25 m 2 at sitting (1.3 m) and standing (1.7 m) heights. Accuracy and jitter were estimated from positional data. The working range was estimated by moving the HMDs away from the cameras until no data were obtained. The HTC Vive provided a working area (24.87 m 2 ) twice as large as that of the Oculus Rift. Both devices showed excellent and comparable performance at sitting height (accuracy up to 1 cm and jitter <0.35 mm), and the HTC Vive presented worse but still excellent accuracy and jitter at standing height (accuracy up to 1.5 cm and jitter <0.5 mm). The HTC Vive presented a larger working range (7 m) than did the Oculus Rift (4.25 m). Our results support the use of these devices for real navigation, exploration, exergaming, and motor rehabilitation in virtual reality environments.

Feasibility and effectiveness of two community-based HIV testing models in rural Swaziland.

PubMed

Parker, Lucy Anne; Jobanputra, Kiran; Rusike, Lorraine; Mazibuko, Sikhathele; Okello, Velephi; Kerschberger, Bernhard; Jouquet, Guillaume; Cyr, Joanne; Teck, Roger

2015-07-01

To evaluate the feasibility (population reached, costs) and effectiveness (positivity rates, linkage to care) of two strategies of community-based HIV testing and counselling (HTC) in rural Swaziland. Strategies used were mobile HTC (MHTC) and home-based HTC (HBHTC). Information on age, sex, previous testing and HIV results was obtained from routine HTC records. A consecutive series of individuals testing HIV-positive were followed up for 6 months from the test date to assess linkage to care. A total of 9 060 people were tested: 2 034 through MHTC and 7 026 through HBHTC. A higher proportion of children and adolescents (<20 years) were tested through HBHTC than MHTC (57% vs. 17%; P < 0.001). MHTC reached a higher proportion of adult men than HBHTC (42% vs. 39%; P = 0.015). Of 398 HIV-positive individuals, only 135 (34%) were enrolled in HIV care within 6 months. Of 42 individuals eligible for antiretroviral therapy, 22 (52%) started treatment within 6 months. Linkage to care was lowest among people who had tested previously and those aged 20-40 years. HBHTC was 50% cheaper (US$11 per person tested; $797 per individual enrolled in HIV care) than MHTC ($24 and $1698, respectively). In this high HIV prevalence setting, a community-based testing programme achieved high uptake of testing and appears to be an effective and affordable way to encourage large numbers of people to learn their HIV status (particularly underserved populations such as men and young people). However, for community HTC to impact mortality and incidence, strategies need to be implemented to ensure people testing HIV-positive in the community are linked to HIV care. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Age-Related Differences in Socio-demographic and Behavioral Determinants of HIV Testing and Counseling in HPTN 043/NIMH Project Accept.

PubMed

Salazar-Austin, N; Kulich, M; Chingono, A; Chariyalertsak, S; Srithanaviboonchai, K; Gray, G; Richter, L; van Rooyen, H; Morin, S; Sweat, M; Mbwambo, J; Szekeres, G; Coates, T; Celentano, D

2018-02-01

Youth represent a large proportion of new HIV infections worldwide, yet their utilization of HIV testing and counseling (HTC) remains low. Using the post-intervention, cross-sectional, population-based household survey done in 2011 as part of HPTN 043/NIMH Project Accept, a cluster-randomized trial of community mobilization and mobile HTC in South Africa (Soweto and KwaZulu Natal), Zimbabwe, Tanzania and Thailand, we evaluated age-related differences among socio-demographic and behavioral determinants of HTC in study participants by study arm, site, and gender. A multivariate logistic regression model was developed using complete individual data from 13,755 participants with recent HIV testing (prior 12 months) as the outcome. Youth (18-24 years) was not predictive of recent HTC, except for high-risk youth with multiple concurrent partners, who were less likely (aOR 0.75; 95% CI 0.61-0.92) to have recently been tested than youth reporting a single partner. Importantly, the intervention was successful in reaching men with site specific success ranging from aOR 1.27 (95% CI 1.05-1.53) in South Africa to aOR 2.30 in Thailand (95% CI 1.85-2.84). Finally, across a diverse range of settings, higher education (aOR 1.67; 95% CI 1.42, 1.96), higher socio-economic status (aOR 1.21; 95% CI 1.08-1.36), and marriage (aOR 1.55; 95% CI 1.37-1.75) were all predictive of recent HTC, which did not significantly vary across study arm, site, gender or age category (18-24 vs. 25-32 years).

Role of male partner involvement in ART retention and adherence in Malawi's Option B+ program.

PubMed

Wesevich, Austin; Mtande, Tiwonge; Saidi, Friday; Cromwell, Elizabeth; Tweya, Hannock; Hosseinipour, Mina C; Hoffman, Irving; Miller, William C; Rosenberg, Nora E

2017-11-01

Malawi's Option B+ program provides all HIV-infected pregnant women free lifelong antiretroviral therapy (ART), but challenges remain regarding retention and ART adherence, potentially due to male partner barriers. We explored relationships between male partner involvement and Option B+ retention and adherence. In 2014, a randomized controlled trial in Malawi compared male recruitment strategies for couple HIV testing and counseling (cHTC) at an antenatal clinic. This secondary analysis was conducted among the entire cohort (N = 200) of women, irrespective of randomization status. We assessed whether cHTC attendance, early disclosure of HIV-positive status, and partner ART reminders were associated with retention and adherence at one month after starting treatment. Retention was defined as attending HIV clinic follow-up within one day of running out of pills. Adherence was defined as taking ≥95% of ARTs by pill count. We used binomial regression to calculate adjusted risk ratios (aRR) and 95% confidence intervals (CI). Median female age was 26 years. Most women (79%) were retained; of these, 68% were adherent. Receiving cHTC was associated with improved retention (aRR 1.33, 95% CI 1.12, 1.59). Receiving male partner ART reminders was weakly associated with retention (aRR 1.16, 95% CI 0.96, 1.39). Disclosure within one day was not associated with retention (aRR 1.08, 95% CI: 0.91, 1.28). Among those who were retained, these three behaviors were not associated with improved 95% adherence. CHTC could play an important role in improving Option B+ retention. Increasing cHTC participation and enhancing adherence-related messages within cHTC are important.

Experimental und numerical investigations on cooling efficiency of Air-Mist nozzles on steel during continuous casting

NASA Astrophysics Data System (ADS)

Arth, G.; Taferner, M.; Bernhard, C.; Michelic, S.

2016-07-01

Cooling strategies in continuous casting of steel can vary from rapid cooling to slow cooling, mainly controlled by adjusting the amount of water sprayed onto the surface of the product. Inadequate adjustment however can lead to local surface undercooling or reheating, leading to surface and inner defects. This paper focuses on cooling efficiency of Air-Mist nozzles on casted steel and the experimental and numerical prediction of surface temperature distributions over the product width. The first part explains the determination of heat transfer coefficients (HTC) on laboratory scale, using a so called nozzle measuring stand (NMS). Based on measured water distributions and determined HTC's for air-mist nozzles using the NMS, surface temperatures are calculated by a transient 2D-model on a simple steel plate, explained in the second part of this paper. Simulations are carried out varying water impact density and spray water distribution, consequently influencing the local HTC distribution over the plate width. Furthermore, these results will be interpreted with regard to their consequence for surface and internal quality of the cast product. The results reveal the difficulty of correct adjustment of the amount of sprayed water, concurrent influencing water distribution and thus changing HTC distribution and surface temperature.

Reliable prediction of heat transfer coefficient in three-phase bubble column reactor via adaptive neuro-fuzzy inference system and regularization network

NASA Astrophysics Data System (ADS)

Garmroodi Asil, A.; Nakhaei Pour, A.; Mirzaei, Sh.

2018-04-01

In the present article, generalization performances of regularization network (RN) and optimize adaptive neuro-fuzzy inference system (ANFIS) are compared with a conventional software for prediction of heat transfer coefficient (HTC) as a function of superficial gas velocity (5-25 cm/s) and solid fraction (0-40 wt%) at different axial and radial locations. The networks were trained by resorting several sets of experimental data collected from a specific system of air/hydrocarbon liquid phase/silica particle in a slurry bubble column reactor (SBCR). A special convection HTC measurement probe was manufactured and positioned in an axial distance of 40 and 130 cm above the sparger at center and near the wall of SBCR. The simulation results show that both in-house RN and optimized ANFIS due to powerful noise filtering capabilities provide superior performances compared to the conventional software of MATLAB ANFIS and ANN toolbox. For the case of 40 and 130 cm axial distance from center of sparger, at constant superficial gas velocity of 25 cm/s, adding 40 wt% silica particles to liquid phase leads to about 66% and 69% increasing in HTC respectively. The HTC in the column center for all the cases studied are about 9-14% larger than those near the wall region.

Making a human right to tobacco control: expert and advocacy networks, framing and the right to health.

PubMed

Reubi, David

2012-01-01

This article addresses the proliferation of human rights in international public health over the last 20 years by examining recent attempts at framing the global smoking epidemic as a human rights problem. Rather than advocating in favour or against human rights-based approaches, the article purports to understand how and why such approaches are being articulated and disseminated. First, it argues that the representation of the global smoking epidemic as a human rights issue has been the product of a small, international network of public health experts and lawyers: the human rights and tobacco control collective or community (HTC). The article describes in particular the HTC's membership, its style of thinking and its efforts to articulate and disseminate human rights-based approaches to tobacco control. Second, the article argues that the aim of the HTC when framing tobacco control as a human rights issue was not to generate public attention for and the political will to tackle the global smoking epidemic, as the literature on framing and human rights presupposes. Instead, as the article shows, the HTC framed tobacco control as a human rights problem to tap into the powerful, judicial monitoring and enforceability mechanisms that make up international human rights.

The influenced of reaction time on the degradation of palm oil empty fruit bunch (EFB) in hydrothermal carbonization

NASA Astrophysics Data System (ADS)

Sarwono, Rakhman; Kurniawan, Hendris Hendarsyah

2017-11-01

Hydrothermal carbonization (HTC) of empty fruit bunch (EFB) of palm oil in different reaction times were investigated. Experiments were carried out in an autoclave at different reaction time of 3,6,9, 15, 20, 25 and 40 hours. With a fixed solid/liquid ratio of 5 gram of EFB in 50 ml water as a solvent, and temperature reaction of 250 °C. Increase the reaction time the soluble products are also increased. The liquid products were analyzed using GCMS to determine the chemical composition. The chemical composition were greatly affected by the reaction time. The main component was glycolic acid, by increasing the reaction time made the varieties of chemical compositions in liquid products, especially for the glycolic acid component, it was decreased slightly. The higher heating value (HHV) also increase slighly by increasing the reaction time both solid and liquid products.

New biotite and muscovite isotopic reference materials, USGS57 and USGS58, for δ2H measurements–A replacement for NBS 30

USGS Publications Warehouse

Qi, Haiping; Coplen, Tyler B.; Gehre, Matthias; Vennemann, Torsten W.; Brand, Willi A.; Geilmann, Heike; Olack, Gerard; Bindeman, Ilya N.; Palandri, Jim; Huang, Li; Longstaffe, Fred J.

2017-01-01

The advent of continuous-flow isotope-ratio mass spectrometry (CF-IRMS) coupled with a high temperature conversion (HTC) system enabled faster, more cost effective, and more precise δ2H analysis of hydrogen-bearing solids. Accurate hydrogen isotopic analysis by on-line or off-line techniques requires appropriate isotopic reference materials (RMs). A strategy of two-point calibrations spanning δ2H range of the unknowns using two RMs is recommended. Unfortunately, the supply of the previously widely used isotopic RM, NBS 30 biotite, is exhausted. In addition, recent measurements have shown that the determination of δ2H values of NBS 30 biotite on the VSMOW-SLAP isotope-delta scale by on-line HTC systems with CF-IRMS may be unreliable because hydrogen in this biotite may not be converted quantitatively to molecular hydrogen. The δ2HVSMOW-SLAP values of NBS 30 biotite analyzed by on-line HTC systems can be as much as 21 mUr (or ‰) too positive compared to the accepted value of − 65.7 mUr, determined by only a few conventional off-line measurements. To ensure accurate and traceable on-line hydrogen isotope-ratio determinations in mineral samples, we here propose two isotopically homogeneous, hydrous mineral RMs with well-characterized isotope-ratio values, which are urgently needed. The U.S. Geological Survey (USGS) has prepared two such RMs, USGS57 biotite and USGS58 muscovite. The δ2H values were determined by both glassy carbon-based on-line conversion and chromium-based on-line conversion, and results were confirmed by off-line conversion. The quantitative conversion of hydrogen from the two RMs using the on-line HTC method was carefully evaluated in this study. The isotopic compositions of these new RMs with 1-σ uncertainties and mass fractions of hydrogen are:USGS57 (biotite)δ2HVSMOW-SLAP = − 91.5 ± 2.4 mUr (n = 24)Mass fraction hydrogen = 0.416 ± 0.002% (n = 4)Mass fraction water = 3.74 ± 0.02% (n = 4)USGS58 (muscovite)δ2HVSMOW-SLAP = − 28.4 ± 1.6 mUr (n = 24)Mass fraction hydrogen = 0.448 ± 0.002% (n = 4)Mass fraction water = 4.03 ± 0.02% (n = 4).These δ2HVSMOW-SLAP values encompass typical ranges for solid unknowns of crustal and mantle origin and are available to users for recommended two-point calibration.

The Accuracy and Precision of Position and Orientation Tracking in the HTC Vive Virtual Reality System for Scientific Research

PubMed Central

Niehorster, Diederick C.; Li, Li; Lappe, Markus

2017-01-01

The advent of inexpensive consumer virtual reality equipment enables many more researchers to study perception with naturally moving observers. One such system, the HTC Vive, offers a large field-of-view, high-resolution head mounted display together with a room-scale tracking system for less than a thousand U.S. dollars. If the position and orientation tracking of this system is of sufficient accuracy and precision, it could be suitable for much research that is currently done with far more expensive systems. Here we present a quantitative test of the HTC Vive’s position and orientation tracking as well as its end-to-end system latency. We report that while the precision of the Vive’s tracking measurements is high and its system latency (22 ms) is low, its position and orientation measurements are provided in a coordinate system that is tilted with respect to the physical ground plane. Because large changes in offset were found whenever tracking was briefly lost, it cannot be corrected for with a one-time calibration procedure. We conclude that the varying offset between the virtual and the physical tracking space makes the HTC Vive at present unsuitable for scientific experiments that require accurate visual stimulation of self-motion through a virtual world. It may however be suited for other experiments that do not have this requirement. PMID:28567271

The Accuracy and Precision of Position and Orientation Tracking in the HTC Vive Virtual Reality System for Scientific Research.

PubMed

Niehorster, Diederick C; Li, Li; Lappe, Markus

2017-01-01

The advent of inexpensive consumer virtual reality equipment enables many more researchers to study perception with naturally moving observers. One such system, the HTC Vive, offers a large field-of-view, high-resolution head mounted display together with a room-scale tracking system for less than a thousand U.S. dollars. If the position and orientation tracking of this system is of sufficient accuracy and precision, it could be suitable for much research that is currently done with far more expensive systems. Here we present a quantitative test of the HTC Vive's position and orientation tracking as well as its end-to-end system latency. We report that while the precision of the Vive's tracking measurements is high and its system latency (22 ms) is low, its position and orientation measurements are provided in a coordinate system that is tilted with respect to the physical ground plane. Because large changes in offset were found whenever tracking was briefly lost, it cannot be corrected for with a one-time calibration procedure. We conclude that the varying offset between the virtual and the physical tracking space makes the HTC Vive at present unsuitable for scientific experiments that require accurate visual stimulation of self-motion through a virtual world. It may however be suited for other experiments that do not have this requirement.

Grassroots community organizations' contribution to the scale-up of HIV testing and counselling services in Zimbabwe.

PubMed

Gregson, Simon; Nyamukapa, Constance A; Sherr, Lorraine; Mugurungi, Owen; Campbell, Catherine

2013-06-19

To investigate whether community engagement (participation in grassroots organizations) contributed to increases in HIV testing in Zimbabwe. Prospective data on membership of local community organizations (e.g. women's groups and burial societies) and uptake of HIV testing and counselling (HTC) and prevention-of-mother-to-child transmission (PMTCT) services were collected from 5260 adults interviewed in two consecutive rounds of a general-population cohort survey in eastern Zimbabwe between 2003 and 2008. The effects of community engagement on uptake of services during the follow-up period were measured using logistic regression to adjust for observed confounding factors. Sixteen percent of men and 47% of women were consistent members of community organizations; 58 and 35% of these people discussed HIV in their meetings and were members of externally sponsored organizations, respectively. Fewer men (10.1%) than women (32.4%) took up HTC during follow-up [adjusted odds ratio (aOR)=4.08, 95% confidence interval (CI) 3.43-4.86, P<0.001]. HTC uptake was higher for members of community organizations than for nonmembers: men, 15.0 versus 9.2% (1.67, 1.15-2.43, P=0.007); women, 35.6 versus 29.6% (1.26, 1.06-1.49, P=0.008). Membership of community organizations showed a nonsignificant association with PMTCT uptake amongst recently pregnant women (42.3 versus 34.2%; 1.30, 0.94-1.78, P=0.1). The most consistent positive associations between community participation and HTC and PMTCT uptake were found in organizations that discussed HIV and when external sponsorship was absent. Grassroots organizations contributed to increased uptake of HTC services in eastern Zimbabwe in the mid-2000s. Partnerships with these organizations could harness community support for the further increases in HIV testing needed in sub-Saharan Africa. © 2013 Creative Common License

Grassroots community organizations’ contribution to the scale-up of HIV testing and counselling services in Zimbabwe

PubMed Central

Gregson, Simon; Nyamukapa, Constance A.; Sherr, Lorraine; Mugurungi, Owen; Campbell, Catherine

2013-01-01

Objective: To investigate whether community engagement (participation in grassroots organizations) contributed to increases in HIV testing in Zimbabwe. Methods: Prospective data on membership of local community organizations (e.g. women's groups and burial societies) and uptake of HIV testing and counselling (HTC) and prevention-of-mother-to-child transmission (PMTCT) services were collected from 5260 adults interviewed in two consecutive rounds of a general-population cohort survey in eastern Zimbabwe between 2003 and 2008. The effects of community engagement on uptake of services during the follow-up period were measured using logistic regression to adjust for observed confounding factors. Results: Sixteen percent of men and 47% of women were consistent members of community organizations; 58 and 35% of these people discussed HIV in their meetings and were members of externally sponsored organizations, respectively. Fewer men (10.1%) than women (32.4%) took up HTC during follow-up [adjusted odds ratio (aOR) = 4.08, 95% confidence interval (CI) 3.43–4.86, P < 0.001]. HTC uptake was higher for members of community organizations than for nonmembers: men, 15.0 versus 9.2% (1.67, 1.15–2.43, P = 0.007); women, 35.6 versus 29.6% (1.26, 1.06–1.49, P = 0.008). Membership of community organizations showed a nonsignificant association with PMTCT uptake amongst recently pregnant women (42.3 versus 34.2%; 1.30, 0.94–1.78, P = 0.1). The most consistent positive associations between community participation and HTC and PMTCT uptake were found in organizations that discussed HIV and when external sponsorship was absent. Conclusion: Grassroots organizations contributed to increased uptake of HTC services in eastern Zimbabwe in the mid-2000s. Partnerships with these organizations could harness community support for the further increases in HIV testing needed in sub-Saharan Africa. PMID:24047764

Nitrogen activation of carbon-encapsulated zero-valent iron nanoparticles and influence of the activation temperature on heavy metals removal

NASA Astrophysics Data System (ADS)

Bonaiti, Stefania; Calderon, Blanca; Collina, Elena; Lasagni, Marina; Mezzanotte, Valeria; Aracil, Ignacio; Fullana, Andrés

2017-05-01

Nanoparticles of zero-valent iron (nZVI) represent a promising agent for environmental remediation. This is due to their core-shell structure which presents the characteristics of both metallic and oxidised iron, leading to sorption and reductive precipitation of metal ions. Nevertheless, nZVI application presents some limitations regarding their rapid oxidation and aggregation in the media which leads to the delivery of the ions after some hours (the “aging effect”). To address these issues, modifications of nZVI structure and synthesis methods have been developed in the last years. The aging problem was solved by using nZVI encapsulated inside carbon spheres (CE-nZVI), synthetized through Hydrothermal Carbonization (HTC). Results showed high heavy metals removal percentage. Furthermore, CE-nZVI were activated with nitrogen in order to increase the metallic iron content. The aim of this study was to test CE-nZVI post-treated with nitrogen at different temperatures in heavy metals removal, demonstrating that the influence of the temperature was negligible in nanoparticles removal efficiency.

Establishment of Hydrographic Shore Control by Doppler Satellite Techniques.

DTIC Science & Technology

1984-06-01

entered in 8116,h 20. if different tromn Report) 10.SPAccuNTRaY NSdrs AHOacurcystndrd, raslcaio, IS. AEY WRDC (Continue en roer@e side it necessary And...the Defense Mapping Agency, Hydrographic-Topographlc Center (DMA-HTC); the ephemerides are computed and distributed by the DMA-HTC [Ref. 3J. The...all,_ C: En m zz E-4~E- 0 .4 0 = 0 z 4 .4 z 4 c -4 4 1 0j 0 heU 7 60 VIII. ACCURACY STANDARDS AND SPECIFICATIONS A. CURRENT ACCURACY

Recent HIV Testing Among Young Men Who Have Sex with Men in Bangkok and Chiang Mai: HIV Testing and Prevention Strategies Must Be Enhanced in Thailand.

PubMed

Johnston, Lisa G; Steinhaus, Mara C; Sass, Justine; Sirinirund, Petchsri; Lee, Catherine; Benjarattanaporn, Patchara; Gass, Robert

2016-09-01

HIV infection among men who have sex with men, particularly in Thai urban settings and among younger cohorts, is escalating. HIV testing and counseling (HTC) are important for prevention and obtaining treatment and care. We examine data from a 2013 survey of males, 15-24 years, reporting past-year sex with a male and living in Bangkok or Chiang Mai. Almost three quarters of young MSM (YMSM) in Bangkok and only 27 % in Chiang Mai had an HIV test in the previous year. Associations for HIV testing varied between cities, although having employment increased the odds of HIV testing for both cities. In Bangkok, family knowledge of same sex attraction and talking to parents/guardians about HIV/AIDS had higher odds of HIV testing. Expanded HTC coverage is needed for YMSM in Chiang Mai. All health centers providing HTC, including those targeting MSM, need to address the specific needs of younger cohorts.

[Therapeutic effect of early applying hydrotherapy with Chinese drugs on children hypoxic ischemic encephalopathy].

PubMed

Ma, Yun-Zhi; Zhai, Hong-Yin; Su, Chun-Ya

2009-02-01

To observe the therapeutic effect of hydrotherapy with Chinese drugs (HT-C) in early intervention on children hypoxic ischemic encephalopathy (HIE). HIE children were assigned to the treatment group and the control group, 50 in each, at random depending on the willingness of patients' parents. Both groups received the conventional functional training, according to the "0 -3-year-old early intervention outline", but for the treatment group, HT-C was applied additionally. Indexes for quality of sleep, gross motor function, severity of spasm and intellectual development were observed and compared before and after treatment to assess the therapeutic effects. Therapeutic effect in the treatment group was better than that in the control group in all the indexes observed, showing statistical significance (all P <0.05). Early intervention of HT-C could improve clinical symptom, promote the functional recovery and intellectual development in children HIE, and also could reduce or prevent the sequelae occurrence of the nervous system in them.

Effects of rice husks and their chars from hydrothermal carbonization on the germination rate and root length of Lepidium sativum

NASA Astrophysics Data System (ADS)

Kern, Jürgen; Mukhina, Irina; Dicke, Christiane; Lanza, Giacomo; Kalderis, Dimitrios

2015-04-01

Currently, char substrates gain a lot of interest, since they are being discussed as a component in growing media, which may become one option for the replacement of peat. Among different thermal conversion processes of biomass hydrothermal carbonization (HTC) has been found to produce chars with similar acidic pH values like peat. The question however is, if these hydrochars, which may contain toxic phenolic compounds are suitable to be introduced as a new substitute for peat in horticulture. In this study rice husk were hydrothermally carbonized at 200° C for 6 hours, yielding in hydrochars containing organic contaminants such as phenols and furfurals, which may affect plants and soil organisms. We investigated potential toxic effects on the germination rate and the root length of cress salad (Lepidium sativum) in four fractions: i) soil control, ii) raw rice husk + soil, iii) unwashed rice char + soil and iv) acetone/water washed rice char + soil. It could be shown that phenols and furfurals, which were removed from the hydrochar after washing by 80 to 96% did not affect the germination rate and the root length of the cress plants. The lowest germination rate and root length were found in the soil control, the highest in the non-washed hydrochar treatment, indicating a fertilization effect and growth stimulation of cress salad by hydrochar. If this result can be confirmed for other target and non-target organisms in future studies, a new strategy for the production of growing media may be developed.

Influence of temperature on nitrogen fate during hydrothermal carbonization of food waste.

PubMed

Wang, Tengfei; Zhai, Yunbo; Zhu, Yun; Peng, Chuan; Xu, Bibo; Wang, Tao; Li, Caiting; Zeng, Guangming

2018-01-01

The influence of temperature (180-260°C) on the fate of nitrogen during hydrothermal carbonization (HTC) of food waste (FW) was assessed. The distribution and evolution of nitrogen in aqueous products and bio-oil, as well as hydrochar, were conducted. Results suggested that elevated temperature enhanced the deamination and the highest ammonium concentration (929.75mg/L) was acquired at 260°C. At temperatures above 220°C, the total N in the hydrochar became stable, whereas the mass percentage of N increased. Amines and heterocyclic-N compounds from protein cracking and Maillard reactions were identified as the main nitrogen-containing compounds in the bio-oil. As to the hydrochar, increasing temperature resulted in condensed nitrogen-containing aromatic heterocycles (e.g. pyridine-N and quaternary-N). In particular, remarkable Maillard reactions at 180°C and the highest temperature at 260°C enhanced nitrogen incorporation (i.e. quaternary-N) into hydrochar. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Status of HIV Testing and Counseling in Kenya: Results From a Nationally Representative Population-Based Survey

PubMed Central

Ng’ang’a, Anne; Waruiru, Wanjiru; Ngare, Carol; Ssempijja, Victor; Gachuki, Thomas; Njoroge, Inviolata; Oluoch, Patricia; Kimanga, Davies O.; Maina, William K.; Mpazanje, Rex; Kim, Andrea A.

2016-01-01

Background HIV testing and counseling (HTC) is essential for successful HIV prevention and treatment programs. The national target for HTC is 80% of the adult population in Kenya. Population-based data to measure progress towards this HTC target are needed to assess the country’s changing needs for HIV prevention and treatment. Methods In 2012–2013, we conducted a national HIV survey among Kenyans aged 18 months to 64 years. Respondents aged 15–64 years were administered a questionnaire that collected information on demographics, HIV testing behavior, and self-reported HIV status. Blood samples were collected for HIV testing in a central laboratory. Participants were offered home-based testing and counseling to learn their HIV status in the home and point-of-care CD4 testing if they tested HIV-positive. Results Of 13,720 adults who were interviewed, 71.6% [95% confidence interval (CI): 70.2 to 73.1] had been tested for HIV. Among those, 56.1% (95% CI: 52.8 to 59.4) had been tested in the past year, 69.4% (95% CI: 68.0 to 70.8) had been tested more than once, and 37.2% (95% CI: 35.7 to 38.8) had been tested with a partner. Fifty-three percent (95% CI: 47.6 to 58.7) of HIV-infected persons were unaware of their infection. Overall 9874 (72.0%) of participants accepted home-based HIV testing and counseling; 4.1% (95% CI: 3.3 to 4.9) tested HIV-positive, and of those, 42.5% (95% CI 31.4 to 53.6) were in need of immediate treatment for their HIV infection but not receiving it. Conclusions HIV testing rates have nearly reached the national target for HTC in Kenya. However, knowledge of HIV status among HIV-infected persons remains low. HTC needs to be expanded to reach more men and couples, and strategies are needed to increase repeat testing for persons at risk for HIV infection. PMID:24732818

What is the cost of providing outpatient HIV counseling and testing and antiretroviral therapy services in selected public health facilities in Nigeria?

PubMed

Aliyu, Husaina Bello; Chuku, Nkata Nwani; Kola-Jebutu, Abimbola; Abubakar, Zubaida; Torpey, Kwasi; Chabikuli, Otto Nzapfurundi

2012-10-01

Limited data on actual cost of providing HIV/AIDS services in Nigeria makes planning difficult. A study was conducted in 9 public health facilities supported by the Global HIV/AIDS Initiative Nigeria. The objective was to determine the cost of outpatient HIV Testing and Counseling (HTC) and antiretroviral therapy (ART) services per patient. Two tertiary and 7 secondary facilities were purposively selected across the six geopolitical regions. Facilities were distributed in urban and rural settings. Utilization and cost data for a 12-month period (January to December 2010) were analyzed. Cost elements included consumables, human resources, infrastructure, trainings, facility management, and Global HIV/AIDS Initiative Nigeria technical support. Total costs were apportioned based on percentage utilization by services, and unit costs were derived by dividing resource inputs by service outputs. Data were analyzed using Microsoft Excel 2003. A sensitivity analysis was also conducted for key assumptions. Mean costs for HTC and ART were US $7.4 and US $209.0, respectively. Costs were higher in Northern facilities (US $6.9, US $250.8), compared with Southern ones (US $6.7, US $194.7); and in tertiary facilities ($18.5, $338.4), compared with secondary ones ($6.3, $204.9). Major cost drivers for HTC and ART were human resources--ranging from 62% to 50%, and ARV drugs--ranging from 54% to 31%, respectively. Governments' ability to negotiate lower priced antiretroviral drugs will be central to reducing the cost of ART. Additionally, use of lower cadre staff to provide HTC will reduce costs and improves efficiency.

Critical Current Test of Liquid Hydrogen Cooled HTC Superconductors under External Magnetic Field

NASA Astrophysics Data System (ADS)

Shirai, Yasuyuki; Shiotsu, Masahiro; Tatsumoto, Hideki; Kobayashi, Hiroaki; Naruo, Yoshihiro; Nonaka, Satoshi; Inatani, Yoshifumi

High-Tc (HTC) superconductors including MgB2 will show excellent properties under temperature of Liquid Hydrogen (LH2:20K), which has large latent heat and low viscosity coefficient. In order to design and fabricate the LH2 cooled superconducting energy devices, we must clear the cooling property of LH2 for superconductors, the cooling system and safety design of LH2 cooled superconducting devices and electro-magnetic property evaluation of superconductors (BSCCO, REBCO and MgB2) and their magnets cooled by LH2. As the first step of the study, an experimental setup which can be used for investigating heat transfer characteristics of LH2 in a pool and also in forced flow (circulation loop with a pump), and also for evaluation of electro-magnetic properties of LH2 cooled superconductors under external magnetic field (up to 7 T). In this paper, we will show a short sketch of the experimental set-up, practical experiences in safety operation of liquid hydrogen cooling system and example test results of critical current evaluation of HTC superconductors cooled by LH2.

Pool-Boiling Heat-Transfer Enhancement on Cylindrical Surfaces with Hybrid Wettable Patterns.

PubMed

Kumar C S, Sujith; Chang, Yao Wen; Chen, Ping-Hei

2017-04-10

In this study, pool-boiling heat-transfer experiments were performed to investigate the effect of the number of interlines and the orientation of the hybrid wettable pattern. Hybrid wettable patterns were produced by coating superhydrophilic SiO2 on a masked, hydrophobic, cylindrical copper surface. Using de-ionized (DI) water as the working fluid, pool-boiling heat-transfer studies were conducted on the different surface-treated copper cylinders of a 25-mm diameter and a 40-mm length. The experimental results showed that the number of interlines and the orientation of the hybrid wettable pattern influenced the wall superheat and the HTC. By increasing the number of interlines, the HTC was enhanced when compared to the plain surface. Images obtained from the charge-coupled device (CCD) camera indicated that more bubbles formed on the interlines as compared to other parts. The hybrid wettable pattern with the lowermost section being hydrophobic gave the best heat-transfer coefficient (HTC). The experimental results indicated that the bubble dynamics of the surface is an important factor that determines the nucleate boiling.

Innovative strategies using communications technologies to engage gay men and other men who have sex with men into early HIV testing and treatment in Thailand.

PubMed

Anand, Tarandeep; Nitpolprasert, Chattiya; Ananworanich, Jintanat; Pakam, Charnwit; Nonenoy, Siriporn; Jantarapakde, Jureeporn; Sohn, Annette H; Phanuphak, Praphan; Phanuphak, Nittaya

2015-04-01

One-in-three men who have sex with men (MSM) surveyed between 2007 and 2010 in Bangkok were HIV infected; 54% of new infections in Thailand are expected to be among MSM. Although MSM are the top internet-accessing population in Thailand, it has not been optimally used to scale up early HIV testing and counselling (HTC) and linkage to treatment. Thailand needs innovative technology-based strategies to help address the exploding epidemic of HIV among gay men and other MSM. Adam's Love, an innovative web-based communications strategy, was launched in 2011 by the Thai Red Cross AIDS Research Centre. It includes a dedicated website, integrated social media and web message boards for online counselling, recruitment and appointment making, a club membership programme offering non-financial incentives for HTC, targeted marketing and promotions, and collaboration with MSM-friendly clinics and private hospitals to improve accessibility of HTC services. Between September 2011 and January 2015, the website engaged 1.69 million viewers, and gained more than 8 million page views. An estimated 11,120 gay men and other MSM received online counselling; 8,288 MSM were referred to HTC services; 1,223 to STI testing services; and 1,112 MSM living with HIV were advised regarding HIV treatment. In total, 1,181 MSM recruited online were enrolled in the club membership programme, and 15.5% were diagnosed with HIV. The Adam's Love programme has successfully demonstrated the potential for utilising 'online-to-offline' recruitment models in Thailand, and has attracted national and regional recognition as a trusted resource on HIV and referral to testing and care.

Different responses of vanillic acid, a phenolic compound, in HTC cells: cytotoxicity, antiproliferative activity, and protection from DNA-induced damage.

PubMed

Almeida, I V; Cavalcante, F M L; Vicentini, V E P

2016-12-19

The consumption of healthy and natural foods has increased over the last few years, primarily because these foods are rich in substances with biological properties of interest, such as exerting anticancer effects and decreasing oxidative stress in living tissues. These foods support adequate nutrition, maintain health, and improve quality of life. Vanillic acid (VA) is a phenolic compound used widely in the food industry as a flavoring, preservative, and food additive. VA can be found in various cereals, whole grains, fruits, herbs, green tea, juices, beers, and wines and possesses antioxidant, hepatoprotective, cardioprotective, and antiapoptotic activities. Studying the cytotoxicity as well as the mutagenic and antimutagenic effects of different concentrations of VA in Rattus norvegicus hepatoma cells (HTC) can identify new cellular activities of this substance. Concentrations up to 100 µM VA are not cytotoxic to HTC cells in a MTT [3-(4,5-dimethilthiazol-2-yl)-2,5-diphenil tetrazolium bromide] assay after 96-h exposure; therefore, VA does not compromise mitochondrial activity. Similarly, concentrations up to 500 µM do not compromise plasma membrane integrity. VA at 10 and 50 µM showed no mutagenic/clastogenic effects, as no significant micronuclei induction was observed. VA 10 µM presented no antiproliferative activity and reduced the cytotoxicity induced by benzo[a]pyrene. The antimutagenic activity of 10 µM VA was observed by the simultaneous, pre-, and post-treatments, as the phenolic compound significantly reduced the frequency of micronuclei induced by the mutagen. These results indicate that VA exerts different responses in HTC cells. Low concentrations present no cytotoxic, mutagenic, or antiproliferative effects and protect cells from DNA damage.

Effects of an HIV peer prevention intervention on sexual and injecting risk behaviors among injecting drug users and their risk partners in Thai Nguyen, Vietnam: A randomized controlled trial

PubMed Central

Go, Vivian F.; Frangakis, Constantine; Le Minh, Nguyen; Latkin, Carl A.; Ha, Tran Viet; Mo, Tran Thi; Sripaipan, Teerada; Davis, Wendy; Zelaya, Carla; Vu, Pham The; Chen, Yong; Celentano, David D.; Quan, Vu Minh

2014-01-01

Globally, 30% of new HIV infections outside sub-Saharan Africa involve injecting drug users (IDU) and in many countries, including Vietnam, HIV epidemics are concentrated among IDU. We conducted a randomized controlled trial in Thai Nguyen, Vietnam, to evaluate whether a peer oriented behavioral intervention could reduce injecting and sexual HIV risk behaviors among IDU and their network members. 419 HIV-negative index IDU aged 18 years or older and 516 injecting and sexual network members were enrolled. Each index participant was randomly assigned to receive a series of six small group peer educator-training sessions and three booster sessions in addition to HIV testing and counseling (HTC) (intervention; n = 210) or HTC only (control; n = 209). Follow-up, including HTC, was conducted at 3, 6, 9 and 12 months post-intervention. The proportion of unprotected sex dropped significantly from 49% to 27% (SE (difference) = 3%, p < 0.01) between baseline and the 3-month visit among all index-network member pairs. However, at 12 months, post-intervention, intervention participants had a 14% greater decline in unprotected sex relative to control participants (Wald test = 10.8, df = 4, p = 0.03). This intervention effect is explained by trial participants assigned to the control arm who missed at least one standardized HTC session during follow-up and subsequently reported increased unprotected sex. The proportion of observed needle/syringe sharing dropped significantly between baseline and the 3-month visit (14% vs. 3%, SE (difference) = 2%, p < 0.01) and persisted until 12 months, but there was no difference across trial arms (Wald test = 3.74, df = 3, p = 0.44). PMID:24034963

Costs along the service cascades for HIV testing and counselling and prevention of mother-to-child transmission

PubMed Central

Bautista-Arredondo, Sergio; Sosa-Rubí, Sandra G.; Opuni, Marjorie; Contreras-Loya, David; Kwan, Ada; Chaumont, Claire; Chompolola, Abson; Condo, Jeanine; Galárraga, Omar; Martinson, Neil; Masiye, Felix; Nsanzimana, Sabin; Ochoa-Moreno, Ivan; Wamai, Richard; Wang’ombe, Joseph

2016-01-01

Objective: We estimate facility-level average annual costs per client along the HIV testing and counselling (HTC) and prevention of mother-to-child transmission (PMTCT) service cascades. Design: Data collected covered the period 2011–2012 in 230 HTC and 212 PMTCT facilities in Kenya, Rwanda, South Africa, and Zambia. Methods: Input quantities and unit prices were collected, as were output data. Annual economic costs were estimated from the service providers’ perspective using micro-costing. Average annual costs per client in 2013 United States dollars (US$) were estimated along the service cascades. Results: For HTC, average cost per client tested ranged from US$5 (SD US$7) in Rwanda to US$31 (SD US$24) in South Africa, whereas average cost per client diagnosed as HIV-positive ranged from US$122 (SD US$119) in Zambia to US$1367 (SD US$2093) in Rwanda. For PMTCT, average cost per client tested ranged from US$18 (SD US$20) in Rwanda to US$89 (SD US$56) in South Africa; average cost per client diagnosed as HIV-positive ranged from US$567 (SD US$417) in Zambia to US$2021 (SD US$3210) in Rwanda; average cost per client on antiretroviral prophylaxis ranged from US$704 (SD US$610) in South Africa to US$2314 (SD US$3204) in Rwanda; and average cost per infant on nevirapine ranged from US$888 (SD US$884) in South Africa to US$2359 (SD US$3257) in Rwanda. Conclusion: We found important differences in unit costs along the HTC and PMTCT service cascades within and between countries suggesting that more efficient delivery of these services is possible. PMID:27753679

Novel SNPs in HSPB8 gene and their association with heat tolerance traits in Sahiwal indigenous cattle.

PubMed

Verma, Nishant; Gupta, Ishwar Dayal; Verma, Archana; Kumar, Rakesh; Das, Ramendra; Vineeth, M R

2016-01-01

Heat shock proteins (HSPs) are expressed in response to heat stress, and the polymorphism in HSP genes at single-nucleotide level has been reported to be associated with heat tolerance and production performance traits in cattle. HSPB8 gene has been mapped on Bos taurus autosome 17 (BTA-17) spanning nearly 13,252 bp and comprising three exons and two introns. The present study was conducted in Sahiwal cows (n = 108) reared in subtropical climate with the objectives to identify SNPs in all three exons and part of intron 1 of HSPB8 gene and to analyze their association with heat tolerance traits in Sahiwal cows. Respiration rate (RR) and rectal temperature (RT) were recorded once during probable extreme hours in different seasons or Temperature-Humidity Index (THI), i.e., winter, spring, and summer. Heat tolerance coefficient (HTC) was also calculated to check the adaptability of the animals during the period of heat stress. The comparative sequence analysis revealed a total two single-nucleotide polymorphisms (SNPs), i.e., g.507G>A in exon 1 and g.881T>C in intron 1 of HSPB8 gene. Out of these two identified SNPs, only one SNP, i.e., g.507G>A, was found to be significantly associated with heat tolerance indicator traits (RR, RT, and HTC) in Sahiwal cows. The perusal of results across different seasons showed the significant (P < 0.01) difference in RR, RT, and HTC between winter, spring, and summer seasons. RR, RT, and HTC were found to be significantly lower (P < 0.01) in GA as compared to GG genotype of g.507G>A SNP of HSPB8 gene. However, in case of another SNP, i.e., g.881T>C, located on intron 1, the RR, RT, and HTC were having non-significant association with the different genotypes, i.e., TT and TC. These findings may partly suggest that GA genotype of SNP g.507G>A of HSPB8 gene has a probable role in heat tolerance in Sahiwal cattle and can therefore be utilized as a marker in propagation of thermo-tolerance cattle in hot tropical and subtropical climate. Nevertheless, the involvement of other regulatory mechanisms cannot be overruled.

Cost and quality of life analysis of HIV self-testing and facility-based HIV testing and counselling in Blantyre, Malawi.

PubMed

Maheswaran, Hendramoorthy; Petrou, Stavros; MacPherson, Peter; Choko, Augustine T; Kumwenda, Felistas; Lalloo, David G; Clarke, Aileen; Corbett, Elizabeth L

2016-02-19

HIV self-testing (HIVST) has been found to be highly effective, but no cost analysis has been undertaken to guide the design of affordable and scalable implementation strategies. Consecutive HIV self-testers and facility-based testers were recruited from participants in a community cluster-randomised trial ( ISRCTN02004005 ) investigating the impact of offering HIVST in addition to facility-based HIV testing and counselling (HTC). Primary costing studies were undertaken of the HIVST service and of health facilities providing HTC to the trial population. Costs were adjusted to 2014 US$ and INT$. Recruited participants were asked about direct non-medical and indirect costs associated with accessing either modality of HIV testing, and additionally their health-related quality of life was measured using the EuroQol EQ-5D. A total of 1,241 participants underwent either HIVST (n = 775) or facility-based HTC (n = 446). The mean societal cost per participant tested through HIVST (US$9.23; 95 % CI: US$9.14-US$9.32) was lower than through facility-based HTC (US$11.84; 95 % CI: US$10.81-12.86). Although the mean health provider cost per participant tested through HIVST (US$8.78) was comparable to facility-based HTC (range: US$7.53-US$10.57), the associated mean direct non-medical and indirect cost was lower (US$2.93; 95 % CI: US$1.90-US$3.96). The mean health provider cost per HIV positive participant identified through HIVST was higher (US$97.50) than for health facilities (range: US$25.18-US$76.14), as was the mean cost per HIV positive individual assessed for anti-retroviral treatment (ART) eligibility and the mean cost per HIV positive individual initiated onto ART. In comparison to the facility-testing group, the adjusted mean EQ-5D utility score was 0.046 (95 % CI: 0.022-0.070) higher in the HIVST group. HIVST reduces the economic burden on clients, but is a costlier strategy for the health provider aiming to identify HIV positive individuals for treatment. The provider cost of HIVST could be substantially lower under less restrictive distribution models, or if costs of oral fluid HIV test kits become comparable to finger-prick kits used in health facilities.

Assessing Hepatitis C Burden and Treatment Effectiveness through the British Columbia Hepatitis Testers Cohort (BC-HTC): Design and Characteristics of Linked and Unlinked Participants

PubMed Central

Janjua, Naveed Zafar; Kuo, Margot; Chong, Mei; Yu, Amanda; Alvarez, Maria; Cook, Darrel; Armour, Rosemary; Aiken, Ciaran; Li, Karen; Mussavi Rizi, Seyed Ali; Woods, Ryan; Godfrey, David; Wong, Jason; Gilbert, Mark; Tyndall, Mark W.; Krajden, Mel

2016-01-01

Background The British Columbia (BC) Hepatitis Testers Cohort (BC-HTC) was established to assess and monitor hepatitis C (HCV) epidemiology, cost of illness and treatment effectiveness in BC, Canada. In this paper, we describe the cohort construction, data linkage process, linkage yields, and comparison of the characteristics of linked and unlinked individuals. Methods The BC-HTC includes all individuals tested for HCV and/or HIV or reported as a case of HCV, hepatitis B (HBV), HIV or active tuberculosis (TB) in BC linked with the provincial health insurance client roster, medical visits, hospitalizations, drug prescriptions, the cancer registry and mortality data using unique personal health numbers. The cohort includes data since inception (1990/1992) of each database until 2012/2013 with plans for annual updates. We computed linkage rates by year and compared the characteristics of linked and unlinked individuals. Results Of 2,656,323 unique individuals available in the laboratory and surveillance data, 1,427,917(54%) were included in the final linked cohort, including about 1.15 million tested for HCV and about 1.02 million tested for HIV. The linkage rate was 86% for HCV tests, 89% for HCV cases, 95% for active TB cases, 48% for HIV tests and 36% for HIV cases. Linkage rates increased from 40% for HCV negatives and 70% for HCV positives in 1992 to ~90% after 2005. Linkage rates were lower for males, younger age at testing, and those with unknown residence location. Linkage rates for HCV testers co-infected with HIV, HBV or TB were very high (90–100%). Conclusion Linkage rates increased over time related to improvements in completeness of identifiers in laboratory, surveillance, and registry databases. Linkage rates were higher for HCV than HIV testers, those testing positive, older individuals, and females. Data from the cohort provide essential information to support the development of prevention, care and treatment initiatives for those infected with HCV. PMID:26954020

Rigorous Performance Evaluation of Smartphone GNSS/IMU Sensors for ITS Applications

PubMed Central

Gikas, Vassilis; Perakis, Harris

2016-01-01

With the rapid growth in smartphone technologies and improvement in their navigation sensors, an increasing amount of location information is now available, opening the road to the provision of new Intelligent Transportation System (ITS) services. Current smartphone devices embody miniaturized Global Navigation Satellite System (GNSS), Inertial Measurement Unit (IMU) and other sensors capable of providing user position, velocity and attitude. However, it is hard to characterize their actual positioning and navigation performance capabilities due to the disparate sensor and software technologies adopted among manufacturers and the high influence of environmental conditions, and therefore, a unified certification process is missing. This paper presents the analysis results obtained from the assessment of two modern smartphones regarding their positioning accuracy (i.e., precision and trueness) capabilities (i.e., potential and limitations) based on a practical but rigorous methodological approach. Our investigation relies on the results of several vehicle tracking (i.e., cruising and maneuvering) tests realized through comparing smartphone obtained trajectories and kinematic parameters to those derived using a high-end GNSS/IMU system and advanced filtering techniques. Performance testing is undertaken for the HTC One S (Android) and iPhone 5s (iOS). Our findings indicate that the deviation of the smartphone locations from ground truth (trueness) deteriorates by a factor of two in obscured environments compared to those derived in open sky conditions. Moreover, it appears that iPhone 5s produces relatively smaller and less dispersed error values compared to those computed for HTC One S. Also, the navigation solution of the HTC One S appears to adapt faster to changes in environmental conditions, suggesting a somewhat different data filtering approach for the iPhone 5s. Testing the accuracy of the accelerometer and gyroscope sensors for a number of maneuvering (speeding, turning, etc.,) events reveals high consistency between smartphones, whereas the small deviations from ground truth verify their high potential even for critical ITS safety applications. PMID:27527187

Rigorous Performance Evaluation of Smartphone GNSS/IMU Sensors for ITS Applications.

PubMed

Gikas, Vassilis; Perakis, Harris

2016-08-05

With the rapid growth in smartphone technologies and improvement in their navigation sensors, an increasing amount of location information is now available, opening the road to the provision of new Intelligent Transportation System (ITS) services. Current smartphone devices embody miniaturized Global Navigation Satellite System (GNSS), Inertial Measurement Unit (IMU) and other sensors capable of providing user position, velocity and attitude. However, it is hard to characterize their actual positioning and navigation performance capabilities due to the disparate sensor and software technologies adopted among manufacturers and the high influence of environmental conditions, and therefore, a unified certification process is missing. This paper presents the analysis results obtained from the assessment of two modern smartphones regarding their positioning accuracy (i.e., precision and trueness) capabilities (i.e., potential and limitations) based on a practical but rigorous methodological approach. Our investigation relies on the results of several vehicle tracking (i.e., cruising and maneuvering) tests realized through comparing smartphone obtained trajectories and kinematic parameters to those derived using a high-end GNSS/IMU system and advanced filtering techniques. Performance testing is undertaken for the HTC One S (Android) and iPhone 5s (iOS). Our findings indicate that the deviation of the smartphone locations from ground truth (trueness) deteriorates by a factor of two in obscured environments compared to those derived in open sky conditions. Moreover, it appears that iPhone 5s produces relatively smaller and less dispersed error values compared to those computed for HTC One S. Also, the navigation solution of the HTC One S appears to adapt faster to changes in environmental conditions, suggesting a somewhat different data filtering approach for the iPhone 5s. Testing the accuracy of the accelerometer and gyroscope sensors for a number of maneuvering (speeding, turning, etc.,) events reveals high consistency between smartphones, whereas the small deviations from ground truth verify their high potential even for critical ITS safety applications.

Assessing Hepatitis C Burden and Treatment Effectiveness through the British Columbia Hepatitis Testers Cohort (BC-HTC): Design and Characteristics of Linked and Unlinked Participants.

PubMed

Janjua, Naveed Zafar; Kuo, Margot; Chong, Mei; Yu, Amanda; Alvarez, Maria; Cook, Darrel; Armour, Rosemary; Aiken, Ciaran; Li, Karen; Mussavi Rizi, Seyed Ali; Woods, Ryan; Godfrey, David; Wong, Jason; Gilbert, Mark; Tyndall, Mark W; Krajden, Mel

2016-01-01

The British Columbia (BC) Hepatitis Testers Cohort (BC-HTC) was established to assess and monitor hepatitis C (HCV) epidemiology, cost of illness and treatment effectiveness in BC, Canada. In this paper, we describe the cohort construction, data linkage process, linkage yields, and comparison of the characteristics of linked and unlinked individuals. The BC-HTC includes all individuals tested for HCV and/or HIV or reported as a case of HCV, hepatitis B (HBV), HIV or active tuberculosis (TB) in BC linked with the provincial health insurance client roster, medical visits, hospitalizations, drug prescriptions, the cancer registry and mortality data using unique personal health numbers. The cohort includes data since inception (1990/1992) of each database until 2012/2013 with plans for annual updates. We computed linkage rates by year and compared the characteristics of linked and unlinked individuals. Of 2,656,323 unique individuals available in the laboratory and surveillance data, 1,427,917(54%) were included in the final linked cohort, including about 1.15 million tested for HCV and about 1.02 million tested for HIV. The linkage rate was 86% for HCV tests, 89% for HCV cases, 95% for active TB cases, 48% for HIV tests and 36% for HIV cases. Linkage rates increased from 40% for HCV negatives and 70% for HCV positives in 1992 to ~90% after 2005. Linkage rates were lower for males, younger age at testing, and those with unknown residence location. Linkage rates for HCV testers co-infected with HIV, HBV or TB were very high (90-100%). Linkage rates increased over time related to improvements in completeness of identifiers in laboratory, surveillance, and registry databases. Linkage rates were higher for HCV than HIV testers, those testing positive, older individuals, and females. Data from the cohort provide essential information to support the development of prevention, care and treatment initiatives for those infected with HCV.

Hydrothermal carbonization of sewage sludge: The effect of feed-water pH on fate and risk of heavy metals in hydrochars.

PubMed

Zhai, Yunbo; Liu, Xiangmin; Zhu, Yun; Peng, Chuan; Wang, Tengfei; Zhu, Luo; Li, Caiting; Zeng, Guangming

2016-10-01

In this study, the effect of feed-water pH (pH=2-12) on fate and risk of heavy metals (HMs) in hydrochars (HCs) was investigated. Hydrothermal carbonization (HTC) of sewage sludge (SS) was carried out with different feed-water pH at 270°C. The research results showed that changing feed-water pH had a positive effect on accumulating Pb, Ni, Cd and Zn in HCs. Chemical forms of Cu and Cr converted from an unstable state to stable in the alkaline environment while in the acidic condition was opposite. The effect of feed-water pH on the chemical forms of HMs was variable but not significant. Risk assessments of Igeo, Er(i), RAC and RI were applied to evaluate the accumulation levels of individual metal, the potential ecological risks, the bio-availabilities and the comprehensive toxicity and sensitivity of HMs, respectively. The lowest pollution level of HMs was obtained at 270°C with pH=11. Copyright © 2016 Elsevier Ltd. All rights reserved.

Shape Engineering of Biomass-Derived Nanoparticles from Hollow Spheres to Bowls via Solvent-Induced Buckling.

PubMed

Chen, Chunhong; Li, Xuefeng; Jiang, Deng; Wang, Zhe; Wang, Yong

2018-06-19

To realize the asymmetry for the hollow carbonaceous nanostructures remains to be a great challenge, especially when biomass is chosen as the carbon resource via hydrothermal carbonization (HTC). Herein, a simple and straightforward solvent induced buckling strategy is demonstrated for the synthesis of asymmetric spherical and bowllike carbonaceous nanomaterials. The formation of the bowllike morphology was attributed to the buckling of the spherical shells induced by the dissolution of the oligomers. The bowllike particles made by this solvent-driven approach demonstrated a well-controlled morphology and a uniform particle size of ~360 nm. The obtained nanospheres and nanobowls can be loaded with CoS2 nanoparticles to act as novel heterogeneous catalysts for the selective hydrogenation of aromatic nitro compounds. With the bowllike structure in hand, as expected, the CoS2/nanobowls catalyst showed good tolerance to a wide scope of reducible groups and afforded both high activity and selectivity in almost all the tested substrates (14). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Research and development to prepare and characterize robust coal/biomass mixtures for direct co-feeding into gasification systems

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

Felix, Larry; Farthing, William; Hoekman, S. Kent

This project was initiated on October 1, 2010 and utilizes equipment and research supported by the Department of Energy, National Energy Technology Laboratory, under Award Number DE- FE0005349. It is also based upon previous work supported by the Department of Energy, National Energy Technology Laboratory, under Award Numbers DOE-DE-FG36-01GOl1082, DE-FG36-02G012011 or DE-EE0000272. The overall goal of the work performed was to demonstrate and assess the economic viability of fast hydrothermal carbonization (HTC) for transforming lignocellulosic biomass into a densified, friable fuel to gasify like coal that can be easily blended with ground coal and coal fines and then be formedmore » into robust, weather-resistant pellets and briquettes.« less

Immersive Visual Data Analysis For Geoscience Using Commodity VR Hardware

NASA Astrophysics Data System (ADS)

Kreylos, O.; Kellogg, L. H.

2017-12-01

Immersive visualization using virtual reality (VR) display technology offers tremendous benefits for the visual analysis of complex three-dimensional data like those commonly obtained from geophysical and geological observations and models. Unlike "traditional" visualization, which has to project 3D data onto a 2D screen for display, VR can side-step this projection and display 3D data directly, in a pseudo-holographic (head-tracked stereoscopic) form, and does therefore not suffer the distortions of relative positions, sizes, distances, and angles that are inherent in 2D projection. As a result, researchers can apply their spatial reasoning skills to virtual data in the same way they can to real objects or environments. The UC Davis W.M. Keck Center for Active Visualization in the Earth Sciences (KeckCAVES, http://keckcaves.org) has been developing VR methods for data analysis since 2005, but the high cost of VR displays has been preventing large-scale deployment and adoption of KeckCAVES technology. The recent emergence of high-quality commodity VR, spearheaded by the Oculus Rift and HTC Vive, has fundamentally changed the field. With KeckCAVES' foundational VR operating system, Vrui, now running natively on the HTC Vive, all KeckCAVES visualization software, including 3D Visualizer, LiDAR Viewer, Crusta, Nanotech Construction Kit, and ProtoShop, are now available to small labs, single researchers, and even home users. LiDAR Viewer and Crusta have been used for rapid response to geologic events including earthquakes and landslides, to visualize the impacts of sealevel rise, to investigate reconstructed paleooceanographic masses, and for exploration of the surface of Mars. The Nanotech Construction Kit is being used to explore the phases of carbon in Earth's deep interior, while ProtoShop can be used to construct and investigate protein structures.

[The balance of harmful trace contaminants between the air humidity condensate and air in a simulator of the Mir orbit station moisture condensation unit].

PubMed

Zlotopol'skiĭ, V M; Smolenskaia, T S

2000-01-01

Subject of the investigation was the balance of harmful trace contaminants (HTC) between the air moisture condensate and air in a simulator of the MIR moisture condensation unit. Experiments involved various classes of water-solvent compounds including alcohols (C1-C4), ketons (C1-C2), aldehydes (C1-C2), fatty acids (C2-C4), esters (acetates C4-C6), and ammonium. For most of the compounds, removal efficiency correlates with air humidity and virtually does not depend on the HTC concentration within the range of 0.25 to 59.1 mg/m3.

Near-field radiative heat transfer between graphene-covered hyperbolic metamaterials

NASA Astrophysics Data System (ADS)

Hong, Xiao-Juan; Li, Jian-Wen; Wang, Tong-Biao; Zhang, De-Jian; Liu, Wen-Xing; Liao, Qing-Hua; Yu, Tian-Bao; Liu, Nian-Hua

2018-04-01

We propose the use of graphene-covered silicon carbide (SiC) nanowire arrays (NWAs) for theoretical studies of near-field radiative heat transfer. The SiC NWAs exhibit a hyperbolic characteristic at an appropriately selected filling-volume fraction. The surface plasmon supported by graphene and the hyperbolic modes supported by SiC NWAs significantly affect radiative heat transfer. The heat-transfer coefficient (HTC) between the proposed structures is larger than that between SiC NWAs. We also find that the chemical potential of graphene plays an important role in modulating the HTC. The tunability of chemical potential through gate voltage enables flexible control of heat transfer using the graphene-covered SiC NWAs.

Lignin Depolymerization with Nitrate-Intercalated Hydrotalcite Catalysts

DOE PAGES

Kruger, Jacob S.; Cleveland, Nicholas S.; Zhang, Shuting; ...

2016-01-13

Hydrotalcites (HTCs) exhibit multiple adjustable parameters to tune catalytic activity, including interlayer anion composition, metal hydroxide layer composition, and catalyst preparation methods. Here in this paper, we report the influence of several of these parameters on β-O-4 bond scission in a lignin model dimer, 2-phenoxy-1-phenethanol (PE), to yield phenol and acetophenone. We find that the presence of both basic and NO 3– anions in the interlayer increases the catalyst activity by 2–3-fold. In contrast, other anions or transition metals do not enhance catalytic activity in comparison to blank HTC. The catalyst is not active for C–C bond cleavage on ligninmore » model dimers and has no effect on dimers without an α-OH group. Most importantly, the catalyst is highly active in the depolymerization of two process-relevant lignin substrates, producing a significant amount of low-molecular-weight aromatic species. The catalyst can be recycled until the NO 3– anions are depleted, after which the activity can be restored by replenishing the NO 3– reservoir and regenerating the hydrated HTC structure. These results demonstrate a route to selective lignin depolymerization in a heterogeneous system with an inexpensive, earth-abundant, commercially relevant, and easily regenerated catalyst.« less

Integration of the HTC Vive into the medical platform MeVisLab

NASA Astrophysics Data System (ADS)

Egger, Jan; Gall, Markus; Wallner, Jürgen; de Almeida Germano Boechat, Pedro; Hann, Alexander; Li, Xing; Chen, Xiaojun; Schmalstieg, Dieter

2017-03-01

Virtual Reality (VR) is an immersive technology that replicates an environment via computer-simulated reality. VR gets a lot of attention in computer games but has also great potential in other areas, like the medical domain. Examples are planning, simulations and training of medical interventions, like for facial surgeries where an aesthetic outcome is important. However, importing medical data into VR devices is not trivial, especially when a direct connection and visualization from your own application is needed. Furthermore, most researcher don't build their medical applications from scratch, rather they use platforms, like MeVisLab, Slicer or MITK. The platforms have in common that they integrate and build upon on libraries like ITK and VTK, further providing a more convenient graphical interface to them for the user. In this contribution, we demonstrate the usage of a VR device for medical data under MeVisLab. Therefore, we integrated the OpenVR library into MeVisLab as an own module. This enables the direct and uncomplicated usage of head mounted displays, like the HTC Vive under MeVisLab. Summarized, medical data from other MeVisLab modules can directly be connected per drag-and-drop to our VR module and will be rendered inside the HTC Vive for an immersive inspection.

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

Green, D.W.; Heinrich, R.R.; Graczyk, D.G.

The ACL activities covered IFR fuel reprocessing, corium-concrete interactions, environmental samples, wastes, WIPP support, Advanced Photon Source, H-Tc superconductors, EBWR vessel, soils, illegal drug detection, quality control, etc.

Spatial and temporal variability of total organic carbon along 140°W in the equatorial Pacific Ocean in 1992

NASA Astrophysics Data System (ADS)

Peltzer, Edward T.; Hayward, Nancy A.

Total organic carbon (TOC) was analyzed on four transects along 140°W in 1992 using a high temperature combustion/discrete injection (HTC/DI) analyzer. For two of the transects, the analyses were conducted on-board ship. Mixed-layer concentrations of organic carbon varied from about 80 μM C at either end of the transect (12°N and 12°S) to about 60 μM C at the equator. Total organic carbon concentrations decreased rapidly below the mixed-layer to about 38-40 μM C at 1000 m across the transect. Little variation was observed below this depth; deep water concentrations below 2000m were virtually monotonic at about 36 μM C. Repeat measurements made on subsequent cruises consistently found the same concentrations at 1000 m or deeper, but substantial variations were observed in the mixed-layer and the upper water column above 400 m depth. Linear mixing models of total organic carbon versus σθ exhibited zones of organic carbon formation and consumption. TOC was found to be inversely correlated with apparent oxygen utilization (AOU) in the region between the mixed-layer and the oxygen minimum. In the mixed-layer, TOC concentrations varied seasonally. Part of the variations in TOC at the equator was driven by changes in the upwelling rate in response to variations in physical forcing related to an El Niño and to the passage of tropical instability waves. TOC export fluxes, calculated from simple box models, averaged 8±4 mmol C m -2day -1 at the equator and also varied seasonally. These export fluxes account for 50-75% of the total carbon deficit and are consistent with other estimates and model predictions.

Effects of an HIV peer prevention intervention on sexual and injecting risk behaviors among injecting drug users and their risk partners in Thai Nguyen, Vietnam: a randomized controlled trial.

PubMed

Go, Vivian F; Frangakis, Constantine; Le Minh, Nguyen; Latkin, Carl A; Ha, Tran Viet; Mo, Tran Thi; Sripaipan, Teerada; Davis, Wendy; Zelaya, Carla; Vu, Pham The; Chen, Yong; Celentano, David D; Quan, Vu Minh

2013-11-01

Globally, 30% of new HIV infections outside sub-Saharan Africa involve injecting drug users (IDU) and in many countries, including Vietnam, HIV epidemics are concentrated among IDU. We conducted a randomized controlled trial in Thai Nguyen, Vietnam, to evaluate whether a peer oriented behavioral intervention could reduce injecting and sexual HIV risk behaviors among IDU and their network members. 419 HIV-negative index IDU aged 18 years or older and 516 injecting and sexual network members were enrolled. Each index participant was randomly assigned to receive a series of six small group peer educator-training sessions and three booster sessions in addition to HIV testing and counseling (HTC) (intervention; n = 210) or HTC only (control; n = 209). Follow-up, including HTC, was conducted at 3, 6, 9 and 12 months post-intervention. The proportion of unprotected sex dropped significantly from 49% to 27% (SE (difference) = 3%, p < 0.01) between baseline and the 3-month visit among all index-network member pairs. However, at 12 months, post-intervention, intervention participants had a 14% greater decline in unprotected sex relative to control participants (Wald test = 10.8, df = 4, p = 0.03). This intervention effect is explained by trial participants assigned to the control arm who missed at least one standardized HTC session during follow-up and subsequently reported increased unprotected sex. The proportion of observed needle/syringe sharing dropped significantly between baseline and the 3-month visit (14% vs. 3%, SE (difference) = 2%, p < 0.01) and persisted until 12 months, but there was no difference across trial arms (Wald test = 3.74, df = 3, p = 0.44). Copyright © 2013 Elsevier Ltd. All rights reserved.

Perceived mHealth barriers and benefits for home-based HIV testing and counseling and other care: Qualitative findings from health officials, community health workers, and persons living with HIV in South Africa

PubMed Central

van Heerden, Alastair; Harris, Danielle M.; van Rooyen, Heidi; Barnabas, Ruanne V.; Ramanathan, Nithya; Ngcobo, Nkosinathi; Mpiyakhe, Zukiswa; Comulada, W. Scott

2017-01-01

mHealth has been proposed to address inefficiencies in the current South African healthcare system, including home-based HIV testing and counseling (HTC) programs. Yet wide-scale adoption of mHealth has not occurred. Even as infrastructure barriers decrease, a need to better understand perceived adoption barriers by stakeholders remains. We conducted focus group discussions (FGD) in South Africa in 2016 with 10 home-based HTC field staff, 12 community health workers (CHWs) and 10 persons living with HIV (PLH). Key informant (KI) interviews were conducted with five health officials. Perceptions about current home-based HTC practices, future mHealth systems and the use of biometrics for patient identification were discussed, recorded and transcribed for qualitative analysis. Themes were based on a conceptual model for perceived mHealth service quality. Stakeholders brought up a lack of communication in sharing patient health information between clinics, between clinics and CHWs, and between clinics and patients as major barriers to care that mHealth can address. CHWs need better patient information from clinics in terms of physical location and health status to plan visitation routes and address patient needs. CHWs perceive that communication barriers create distrust towards them by clinic staff. PLH want automated appointment and medication reminders. KI see mHealth as a way to improve health information transfer to government officials to better allocate healthcare resources. Stakeholders are also optimistic about the ability for biometrics to improve patient identification but disagreed as to which biometrics would be acceptable, especially in older patients. All stakeholders provided useful information towards the development of mHealth systems. Hospitals are adopting patient-centered approaches that solicit feedback from patients and incorporate them into decision-making processes. A similar approach is needed in the development of mHealth systems. Further, such systems are critical to the successful extension of the health system from health facilities into people’s homes. PMID:28475904

Perceived mHealth barriers and benefits for home-based HIV testing and counseling and other care: Qualitative findings from health officials, community health workers, and persons living with HIV in South Africa.

PubMed

van Heerden, Alastair; Harris, Danielle M; van Rooyen, Heidi; Barnabas, Ruanne V; Ramanathan, Nithya; Ngcobo, Nkosinathi; Mpiyakhe, Zukiswa; Comulada, W Scott

2017-06-01

mHealth has been proposed to address inefficiencies in the current South African healthcare system, including home-based HIV testing and counseling (HTC) programs. Yet wide-scale adoption of mHealth has not occurred. Even as infrastructure barriers decrease, a need to better understand perceived adoption barriers by stakeholders remains. We conducted focus group discussions (FGD) in South Africa in 2016 with 10 home-based HTC field staff, 12 community health workers (CHWs) and 10 persons living with HIV (PLH). Key informant (KI) interviews were conducted with five health officials. Perceptions about current home-based HTC practices, future mHealth systems and the use of biometrics for patient identification were discussed, recorded and transcribed for qualitative analysis. Themes were based on a conceptual model for perceived mHealth service quality. Stakeholders brought up a lack of communication in sharing patient health information between clinics, between clinics and CHWs, and between clinics and patients as major barriers to care that mHealth can address. CHWs need better patient information from clinics in terms of physical location and health status to plan visitation routes and address patient needs. CHWs perceive that communication barriers create distrust towards them by clinic staff. PLH want automated appointment and medication reminders. KI see mHealth as a way to improve health information transfer to government officials to better allocate healthcare resources. Stakeholders are also optimistic about the ability for biometrics to improve patient identification but disagreed as to which biometrics would be acceptable, especially in older patients. All stakeholders provided useful information towards the development of mHealth systems. Hospitals are adopting patient-centered approaches that solicit feedback from patients and incorporate them into decision-making processes. A similar approach is needed in the development of mHealth systems. Further, such systems are critical to the successful extension of the health system from health facilities into people's homes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cloudsat tropical cyclone database

NASA Astrophysics Data System (ADS)

Tourville, Natalie D.

CloudSat (CS), the first 94 GHz spaceborne cloud profiling radar (CPR), launched in 2006 to study the vertical distribution of clouds. Not only are CS observations revealing inner vertical cloud details of water and ice globally but CS overpasses of tropical cyclones (TC's) are providing a new and exciting opportunity to study the vertical structure of these storm systems. CS TC observations are providing first time vertical views of TC's and demonstrate a unique way to observe TC structure remotely from space. Since December 2009, CS has intersected every globally named TC (within 1000 km of storm center) for a total of 5,278 unique overpasses of tropical systems (disturbance, tropical depression, tropical storm and hurricane/typhoon/cyclone (HTC)). In conjunction with the Naval Research Laboratory (NRL), each CS TC overpass is processed into a data file containing observational data from the afternoon constellation of satellites (A-TRAIN), Navy's Operational Global Atmospheric Prediction System Model (NOGAPS), European Center for Medium range Weather Forecasting (ECMWF) model and best track storm data. This study will describe the components and statistics of the CS TC database, present case studies of CS TC overpasses with complementary A-TRAIN observations and compare average reflectivity stratifications of TC's across different atmospheric regimes (wind shear, SST, latitude, maximum wind speed and basin). Average reflectivity stratifications reveal that characteristics in each basin vary from year to year and are dependent upon eye overpasses of HTC strength storms and ENSO phase. West Pacific (WPAC) basin storms are generally larger in size (horizontally and vertically) and have greater values of reflectivity at a predefined height than all other basins. Storm structure at higher latitudes expands horizontally. Higher vertical wind shear (≥ 9.5 m/s) reduces cloud top height (CTH) and the intensity of precipitation cores, especially in HTC strength storms. Average zero and ten dBZ height thresholds confirm WPAC storms loft precipitation sized particles higher into the atmosphere than in other basins. Two CS eye overpasses (32 hours apart) of a weakening Typhoon Nida in 2009 reveal the collapse of precipitation cores, warm core anomaly and upper tropospheric ice water content (IWC) under steady moderate shear conditions.

Effect of Hemoconcentration on Dural Sinus Computed Tomography Density in a Pediatric Population.

PubMed

Yurttutan, Nursel; Kizildag, Betul; Sarica, Mehmet Akif; Baykara, Murat

2016-10-01

Unenhanced brain computed tomography (CT) is inexpensive, easily available, and the first-choice imaging modality for patients presenting with various neurologic symptoms. Venous thrombosis is not rare in childhood, but diagnosis can be difficult. In some cases, only denser vessels can be used to highlight an issue. The aim of this study was to retrospectively evaluate the relationship between X-ray attenuation and hemoconcentration in a pediatric population. This study enrolled 99 pediatric patients who had been referred radiology department for unenhanced brain CT. Images were retrospectively evaluated for measurement of dural sinus densities from four distinct dural sinus locations. Correlation between mean Hounsfield unit (HU) values and hemoglobin/hematocrit (Hb/Htc) levels, as well as age and gender were further analyzed. There was a strong correlation between mean HU and Hb levels (r = 0.411; standard deviation: 0.001) and also between mean HU and Htc levels (r = 0.393; p < 0.001). According to the results of this study, the mean sinus density and H:H (HU:Htc) values were 44.06 HU and 1.19, respectively, in a normal pediatric group. In conclusion, before deciding between a diagnosis of thrombosis and a determination of normal findings during an evaluation of unenhanced CT in a pediatric population, radiologists should consider complete blood count results as well as H:H ratios. Georg Thieme Verlag KG Stuttgart · New York.

HTC Vive MeVisLab integration via OpenVR for medical applications

PubMed Central

Egger, Jan; Gall, Markus; Wallner, Jürgen; Boechat, Pedro; Hann, Alexander; Li, Xing; Chen, Xiaojun; Schmalstieg, Dieter

2017-01-01

Virtual Reality, an immersive technology that replicates an environment via computer-simulated reality, gets a lot of attention in the entertainment industry. However, VR has also great potential in other areas, like the medical domain, Examples are intervention planning, training and simulation. This is especially of use in medical operations, where an aesthetic outcome is important, like for facial surgeries. Alas, importing medical data into Virtual Reality devices is not necessarily trivial, in particular, when a direct connection to a proprietary application is desired. Moreover, most researcher do not build their medical applications from scratch, but rather leverage platforms like MeVisLab, MITK, OsiriX or 3D Slicer. These platforms have in common that they use libraries like ITK and VTK, and provide a convenient graphical interface. However, ITK and VTK do not support Virtual Reality directly. In this study, the usage of a Virtual Reality device for medical data under the MeVisLab platform is presented. The OpenVR library is integrated into the MeVisLab platform, allowing a direct and uncomplicated usage of the head mounted display HTC Vive inside the MeVisLab platform. Medical data coming from other MeVisLab modules can directly be connected per drag-and-drop to the Virtual Reality module, rendering the data inside the HTC Vive for immersive virtual reality inspection. PMID:28323840

Antiproliferative effect of a food coloring on colon cancer cell line.

PubMed

Norizadeh Tazehkand, M

2017-01-01

4-MEI (4-Methylimidazole) is used as a chemical intermediate, crude material or component in the manufacture of pharmaceuticals, photographic and photothermographic chemicals, dyes and pigments and agricultural chemicals. 4-MEI is unintentionally found in our food. Caramel colour (which is the most used beverage colouring and food), dark beers and common brands of cola drinks may comprise more than 100 μg of this compound per 12-ounce serving. 4-MEI is widely used by people and colon cancer is common in our countries. So, it was decided to do in vitro analysis of anti-cancer effect of 4-MEI by MTT test using htc-116 cell line.In this study, mouse Htc-116 cell line was treated with 4-MEI concentrations of 300, 450, 600 and 750 µg/mL for 24 hours and 48 hours periods, after that antiproliferative effect of the 4-MEI was studied by MTT assay. In this study 4-MEI at highest concentration of 24h and at all concentration for 48 h treatment time significantly inhibited cell proliferation when it was compared to control. Also, exposing to the 4-MEI for 48 hours led to a decrease in cells proliferation by concentration dependent manner. This result showed that 4-MEI had anticancer effect in htc-116 cells. However, it has to be evaluated with different new studies (Tab. 1, Fig. 4, Ref. 19).

HTC Vive MeVisLab integration via OpenVR for medical applications.

PubMed

Egger, Jan; Gall, Markus; Wallner, Jürgen; Boechat, Pedro; Hann, Alexander; Li, Xing; Chen, Xiaojun; Schmalstieg, Dieter

2017-01-01

Virtual Reality, an immersive technology that replicates an environment via computer-simulated reality, gets a lot of attention in the entertainment industry. However, VR has also great potential in other areas, like the medical domain, Examples are intervention planning, training and simulation. This is especially of use in medical operations, where an aesthetic outcome is important, like for facial surgeries. Alas, importing medical data into Virtual Reality devices is not necessarily trivial, in particular, when a direct connection to a proprietary application is desired. Moreover, most researcher do not build their medical applications from scratch, but rather leverage platforms like MeVisLab, MITK, OsiriX or 3D Slicer. These platforms have in common that they use libraries like ITK and VTK, and provide a convenient graphical interface. However, ITK and VTK do not support Virtual Reality directly. In this study, the usage of a Virtual Reality device for medical data under the MeVisLab platform is presented. The OpenVR library is integrated into the MeVisLab platform, allowing a direct and uncomplicated usage of the head mounted display HTC Vive inside the MeVisLab platform. Medical data coming from other MeVisLab modules can directly be connected per drag-and-drop to the Virtual Reality module, rendering the data inside the HTC Vive for immersive virtual reality inspection.

Hard-to-cook phenomenon in chickpeas (Cicer arietinum L): effect of accelerated storage on quality.

PubMed

Reyes-Moreno, C; Okamura-Esparza, J; Armienta-Rodelo, E; Gómez-Garza, R M; Milán-Carrillo, J

2000-01-01

Storage, at high temperature (> or = 25 degrees C) and high relative humidity (> or = 65%), causes development of hard to cook (HTC) phenomenon in grain legumes. The objective of this work was to study the effect of storage simulating tropical conditions on chickpeas quality. The hardening of the Surutato 77, Mocorito 88, and Blanco Sinaloa 92 chickpea varieties was produced using adverse storage (32 +/- 1 degrees C, RH = 75%, 160 days) conditions. For all samples, the Hunter 'L' values decreased and deltaE values increased during storage, meaning a loss of color lightness and development of darkening. Accelerated storage caused a significant decrease in the water absorption capacities and cooking times of whole seeds, cotyledons and seed coats of all samples, being more pronounced in The Blanco Sinaloa 92 variety. Furthermore, storage produced significant decreases in the seed coat tannin content of the three materials; this parameter increased significantly in the cotyledon. In all samples, the levels of phytic acid decreased significantly with the seed hardness. Hardening of chickpea grains caused a decrease in the in vitro protein digestibilities of all varieties. These results suggest that both the cotyledon and seed coat play a significant role in the process of chickpea hardening. Blanco Sinaloa 92 and Mocorito 88 might be classified as varieties with high and low proneness, respectively, to the development of the HTC condition.

High throughput computing: a solution for scientific analysis

USGS Publications Warehouse

O'Donnell, M.

2011-01-01

handle job failures due to hardware, software, or network interruptions (obviating the need to manually resubmit the job after each stoppage); be affordable; and most importantly, allow us to complete very large, complex analyses that otherwise would not even be possible. In short, we envisioned a job-management system that would take advantage of unused FORT CPUs within a local area network (LAN) to effectively distribute and run highly complex analytical processes. What we found was a solution that uses High Throughput Computing (HTC) and High Performance Computing (HPC) systems to do exactly that (Figure 1).

Impact of hydrochar on rice paddy CH4 and N2O emissions: A comparative study with pyrochar.

PubMed

Zhou, Beibei; Feng, Yanfang; Wang, Yueman; Yang, Linzhang; Xue, Lihong; Xing, Baoshan

2018-08-01

Hydrothermal carbonization (HTC) thermally converts wet biomasses to carbon materials, dramatically reducing energy use for drying and improving solid product yield compared to pyrolysis process. However, researches regarding agricultural usage of hydrochar (HC) are limited. In the present study, the influence of HC amendment on CH 4 and N 2 O emissions, as well as global warming potential (GWP) and greenhouse gas intensity (GHGI) were investigated. Additionally, pyrochar (PC) treatments as well as two char-free control treatments with (CKU) or without (CK) N fertilizer were also included for comparison. Chars were produced from wheat straw (WC) and saw dust (SC) and applied at different rates (0.5% and 3%, w/w). Both hydrochar and pyrochar decreased paddy CH 4 emissions when amended at a lower rate (0.5%) compared to CKU treatment, which was more obvious for pyrochar when applied at the rate of 3%. Contrarily, 3%-HC significantly stimulated CH 4 emissions, which were around 5 and 3 times higher than that of CKU for WC and SC, respectively. Furthermore, hydrochar showed the potential to decrease paddy N 2 O emissions (6.06-32.32%) at both application rates. However, N 2 O emissions with PC treatments varied depending on application rate (20.20-75.76%). GWP and GHGI values of 0.5%-HC and PC treatments were similar, 6.67-25.00% and 3.85-25.00% lower than those of CKU treatment, respectively. However, 3%-HC amendments led to significantly increased GWP and GHGI. This study suggested that application rate of hydrochar used in rice fields should be taken into serious consideration to fulfill its potential in GHGs mitigation and minimize environmental side effects. Copyright © 2018 Elsevier Ltd. All rights reserved.

Same day HIV diagnosis and antiretroviral therapy initiation affects retention in Option B+ prevention of mother-to-child transmission services at antenatal care in Zomba District, Malawi.

PubMed

Chan, Adrienne K; Kanike, Emmanuel; Bedell, Richard; Mayuni, Isabel; Manyera, Ruth; Mlotha, William; Harries, Anthony D; van Oosterhout, Joep J; van Lettow, Monique

2016-01-01

Data from the Option B+ prevention of mother-to-child transmission (PMTCT) program in Malawi show considerable variation between health facilities in retention on antiretroviral therapy (ART). In a programmatic setting, we studied whether the "model of care," based on the degree of integration of antenatal care (ANC), HIV testing and counselling (HTC) and ART service provision-influenced uptake of and retention on ART. We conducted a retrospective cohort study of pregnant women seeking ANC at rural primary health facilities in Zomba District, Malawi. Data were extracted from standardized national ANC registers, ART registers and ART master cards. The "model of care" of Option B+ service delivery was determined at each health facility, based on the degree of integration of ANC, HTC and ART. Full integration (Model 1) of HTC and ART initiation at ANC was compared with integration of HTC only into ANC services (Model 2) with subsequent referral to an existing ART clinic for treatment initiation. A total of 10,528 women were newly registered at ANC between October 2011 and March 2012 in 23 rural health facilities (12 were Model 1 and 11 Model 2). HIV status was ascertained in 8,572 (81%) women. Among 914/8,572 (9%) HIV-positive women enrolling at ANC, 101/914 (11%) were already on ART; of those not on treatment, 456/813 (56%) were started on ART. There was significantly higher ART uptake in Model 1 compared with Model 2 sites (63% vs. 51%; p=0.001), but significantly lower ART retention in Model 1 compared with Model 2 sites (79% vs. 87%; p=0.02). Multivariable analysis showed that initiation of ART on the same day as HIV diagnosis, but not model of care, was independently associated with reduced retention in the first six months (adjusted odds ratio 2.27; 95% CI: 1.34-3.85; p=0.002). HIV diagnosis and treatment on the same day was associated with reduced retention on ART, independent of the level of PMTCT service integration at ANC.

Tonian paleomagnetism of the red beds of Madiyi Formation, lower Banxi Group in South China: implications for pre-Sturtian climate, Rodinia reconstruction and true polar wander

NASA Astrophysics Data System (ADS)

Hanbiao, X.; Zhang, S.; Xiao, Q.; Li, H.; Chang, L.; Fu, H.; Liu, R.

2017-12-01

We present a new Tonian paleomagnetic pole from the red beds of ca. 810 Ma Madiyi Formation, lower Banxi Group in the central South China Block (SCB). Detailed thermal demagnetization reveals two distinct magnetic components among the samples. A low temperature component (LTC), removed from almost all the samples below 580°C, yielded a paleopole at 68.0°N, 211.7°E (A95=1.9) that is close to the pole of late Jurassic. The high temperature component (HTC), isolated between 580-690°C, gave a mean direction of D=310.0°, I=57.4°, α95=3.7 (108 samples of 13 sites) after bedding correction, corresponding to a paleomagnetic pole at 47.6°N, 46.7°E (A95=5.6°). The HTC passed a reversal test on 95% and 99% confidence level. Directional distribution of the HTC show significant elongation which may indicate inclination shallowing, and the inclination was corrected to 75.1° using E/I technique, corresponding to a paleolatitude at 60.8±3.4° of research area. The paleopole calculated from the E/I-corrected HTC is at 44.8°N, 80.2°E (A95=3.4°), being significantly distinct from any younger poles of the SCB. This new pole plus existing high quality paleomagnetic poles from the SCB demonstrate that the SCB experienced a polar-equatorial region drifting tendency from 825 Ma to Cambrian. The high-paleolatitude red beds rather than glacial sediments deposited in the SCB, combined with coeval widespread evaporative in other continents, possibly suggest pre-Cryogenian global greenhouse climate. In our reconstruction at 800 Ma, the SCB was placed on the northwest periphery of Rodinia, with its western margin adjacent to the northern India, rather than occupying a central position of Rodinia. The distribution of 825-750 Ma poles of the SCB, East Svalbard, Australia, Laurentia, India along a great arc may be associated with true polar wander around 800 Ma.

Same day ART initiation versus clinic-based pre-ART assessment and counselling for individuals newly tested HIV-positive during community-based HIV testing in rural Lesotho - a randomized controlled trial (CASCADE trial).

PubMed

Labhardt, Niklaus Daniel; Ringera, Isaac; Lejone, Thabo Ishmael; Masethothi, Phofu; Thaanyane, T'sepang; Kamele, Mashaete; Gupta, Ravi Shankar; Thin, Kyaw; Cerutti, Bernard; Klimkait, Thomas; Fritz, Christiane; Glass, Tracy Renée

2016-04-14

Achievement of the UNAIDS 90-90-90 targets in Sub-Sahara Africa is challenged by a weak care-cascade with poor linkage to care and retention in care. Community-based HIV testing and counselling (HTC) is widely used in African countries. However, rates of linkage to care and initiation of antiretroviral therapy (ART) in individuals who tested HIV-positive are often very low. A frequently cited reason for non-linkage to care is the time-consuming pre-ART assessment often requiring several clinic visits before ART-initiation. This two-armed open-label randomized controlled trial compares in individuals tested HIV-positive during community-based HTC the proposition of same-day community-based ART-initiation to the standard of care pre-ART assessment at the clinic. Home-based HTC campaigns will be conducted in catchment areas of six clinics in rural Lesotho. Households where at least one individual tested HIV positive will be randomized. In the standard of care group individuals receive post-test counselling and referral to the nearest clinic for pre-ART assessment and counselling. Once they have started ART the follow-up schedule foresees monthly clinic visits. Individuals randomized to the intervention group receive on the spot point-of-care pre-ART assessment and adherence counselling with the proposition to start ART that same day. Once they have started ART, follow-up clinic visits will be less frequent. First primary outcome is linkage to care (individual presents at the clinic at least once within 3 months after the HIV test). The second primary outcome is viral suppression 12 months after enrolment in the study. We plan to enrol a minimum of 260 households with 1:1 allocation and parallel assignment into both arms. This trial will show if in individuals tested HIV-positive during community-based HTC campaigns the proposition of same-day ART initiation in the community, combined with less frequent follow-up visits at the clinic could be a pragmatic approach to improve the care cascade in similar settings. NCT02692027 , registered February 21, 2016.

Identification of multiple magnetizations of the Ediacaran strata in South China

NASA Astrophysics Data System (ADS)

Jing, Xianqing; Yang, Zhenyu; Tong, Yabo; Wang, Heng; Xu, Yingchao

2018-01-01

A suspected Silurian remagnetization of the Ediacaran strata of South China was proposed decades ago by many researchers, but, there has been no systematic study of its causes and mechanisms. In this study, we investigate the multiphase remagnetization processes that affected the Ediacaran strata and the possible mechanisms of these remagnetization events. We conducted detailed palaeomagnetic, rock magnetic and scanning electron microscope (SEM) studies of samples from the Ediacaran strata in the Jiulongwan (JLWE, JLWS), Qinglinkou (QLK) and Sanxiarenjia (SXRJ) sections in the Three Gorges Area, South China. After removal of a recent viscous remanent magnetization below 150 °C, an intermediate temperature component (ITC; Dg = 27.6°, Ig = 45.3°, N = 12 sites, kg = 184.3, α95 = 3.2° for JLWE; Dg = 22°, Ig = 45.3°, N = 11 sites, kg = 789.2, α95 = 1.6° for JLWS; and Dg = 25.5°, Ig = 52.5°, N = 6 sites, kg = 533.4, α95 = 2.9° for SXRJ) was removed below 300 °C which coincides with the Jurassic results from South China, suggesting a pervasive Jurassic remagnetization. In addition, a high temperature component (HTC; Ds = 84.8°, Is = 19.2°, N = 9 sites, ks = 35.5, α95 = 8.8° for JLWE; Ds = 74.1°, Is = 49.4°, N = 7 sites, ks = 218.9, α95 = 4.1° for JLWS; and Ds = 89.5°, Is = 30.7°, N = 8 sites, ks = 129.2, α95 = 4.9° for SXRJ) was isolated between 300 and 480-540 °C. Rock magnetic and SEM studies suggest that the ITC and HTC are carried by pyrrhotite and magnetite, respectively. SEM observations also demonstrate the occurrence of massive authigenic magnetite in cavities or cracks, mineralogical changes from pyrite to Fe oxides, and the reaction between gypsum and Fe oxides. Based on similarities to the Silurian poles of South China, together with the SEM observations, we suggest that the HTC from the JLWE and SXRJ sections is a Silurian age remagnetization. The oxidation of iron sulphides and thermochemical sulphate reduction induced by the multiple generations of oil and gas in the Ediacaran and Cambrian strata are suggested as the main mechanism for remagnetization. Despite the pervasive Silurian remagnetization of the Ediacaran strata, most of the HTC from the thick-bedded dolostone of Doushantuo Formation Member 3 at the JLWS section appears to carry a primary remanence, because its pole differs from other poles of South China and the results pass both the fold and reversal tests. The relatively low-geothermic conditions and the absence of both hydrocarbon and smectite/illite explain why most results from the Doushantuo Member 3 of JLWS section were not affected by the Silurian remagnetization. This new Ediacaran pole supersedes the previous suspected remagnetized poles, which can be used to constrain the palaeoposition of South China both in Rodinia and Gondwana.

Genotoxic evaluation of an industrial effluent from an oil refinery using plant and animal bioassays.

PubMed

Rodrigues, Fernando Postalli; Angeli, José Pedro Friedmann; Mantovani, Mário Sérgio; Guedes, Carmen Luisa Barbosa; Jordão, Berenice Quinzani

2010-01-01

Polycyclic aromatic hydrocarbons (PAHs) are genotoxic chemicals commonly found in effluents from oil refineries. Bioassays using plants and cells cultures can be employed for assessing environmental safety and potential genotoxicity. In this study, the genotoxic potential of an oil refinery effluent was analyzed by means of micronucleus (MN) testing of Alium cepa, which revealed no effect after 24 h of treatment. On the other hand, primary lesions in the DNA of rat (Rattus norvegicus) hepatoma cells (HTC) were observed through comet assaying after only 2 h of exposure. On considering the capacity to detect DNA damage of a different nature and of these cells to metabolize xenobiotics, we suggest the association of the two bioassays with these cell types, plant (Allium cepa) and mammal (HTC) cells, for more accurately assessing genotoxicity in environmental samples.

Bone disease in patients awaiting liver transplantation. Has the situation improved in the last two decades?

PubMed

Monegal, Ana; Navasa, Miquel; Peris, Pilar; Colmenero, Jordi; Cuervo, Andrea; Muxí, Africa; Gifre, Laia; Guañabens, Núria

2013-12-01

In recent years, there has been speculation about the possibility of a reduction in the incidence of fractures after liver transplantation (LT) because of changes in the characteristics of candidates and the use of different immunosuppressive therapies. We analyzed the characteristics of LT candidates (CTC) and compared them with historical data from a group of LT candidate patients (HTC). Data from 60 CTC patients consecutively included in a screening program of metabolic bone disease were compared with data from 60 HTC patients prospectively evaluated between 1992 and 1993. In all patients, we analyzed the clinical and laboratory characteristics, bone mineral density (BMD) dual-energy X-ray absorptiometry, and skeletal fractures. Patients in the CTC group were older than patients in the HTC group. The CTC group had lower femoral neck T scores. No differences were observed between groups in the proportion of patients with osteoporosis (22 vs. 30 %, p = ns) or fractures (36 vs. 33 %, p = ns). The percentage of patients with normal BMD decreased from 38 to 20 %. 25(OH)D values were low in both groups. Only 7.5 % of the CTC patients received calcium and/or vitamin D supplementation. The prevalence of fractures among CTC patients was similar to that seen two decades ago. At present, candidates for LT are older and have lower femoral bone mass. Vitamin D deficiency remains frequent; however, calcium and/or vitamin D supplementation is uncommon.

Bubble induced flow field modulation for pool boiling enhancement over a tubular surface

NASA Astrophysics Data System (ADS)

Raghupathi, P. A.; Joshi, I. M.; Jaikumar, A.; Emery, T. S.; Kandlikar, S. G.

2017-06-01

We demonstrate the efficacy of using a strategically placed enhancement feature to modify the trajectory of bubbles nucleating on a horizontal tubular surface to increase both the critical heat flux (CHF) and the heat transfer coefficient (HTC). The CHF on a plain tube is shown to be triggered by a local dryout at the bottom of the tube due to vapor agglomeration. To mitigate this effect and delay CHF, the nucleating bubble trajectory is modified by incorporating a bubble diverter placed axially at the bottom of the tube. The nucleating bubble at the base of the diverter experiences a tangential evaporation momentum force (EMF) which causes the bubble to grow sideways away from the tube and avoid localized bubble patches that are responsible for CHF initiation. High speed imaging confirmed the lateral displacement of the bubbles away from the diverter closely matched with the theoretical predictions using EMF and buoyancy forces. Since the EMF is stronger at higher heat fluxes, bubble displacement increases with heat flux and results in the formation of separate liquid-vapor pathways wherein the liquid enters almost unobstructed at the bottom and the vapor bubble leaves sideways. Experimental results yielded CHF and HTC enhancements of ˜60% and ˜75%, respectively, with the diverter configuration when compared to a plain tube. This work can be used for guidance in developing enhancement strategies to effectively modulate the liquid-vapor flow around the heater surface at various locations to enhance HTC and CHF.

Factor for felons: how can we provide haemophilia care to the incarcerated?

PubMed

Lambing, A; Kachalsky, E; Mueller, L M; Kuriakose, P

2015-11-01

In 2011, 6.98-million offenders were documented in the adult correctional system, with state operating costs designated 12% towards medical care ($11.97 day per inmate) for the general population. Common co-existing health problems identified are: arthritis (13%), hypertension (11%), asthma (10%) and heart problems (6%). Less than 5% of inmates have health issues related to cancer, diabetes, liver or renal problems and communicable diseases. The leading cause of death is suicide (33.2%), followed by heart disease (26.1%). Despite these statistics quality is lacking. Given these statistics, one would expect that a small proportion of patients from Hemophilia Treatment Center (HTC) will spend some time within the justice system. Currently there are no data addressing haemophilia care needs while incarcerated. This article will review the current health care issues in the adult correctional system. Additionally, six case reports of incarcerated haemophiliacs will be highlighted exploring the successes and challenges with maintaining haemophilia care addressing the priority of meeting the haemophilia care needs verses the penal system regulations. It can be expected that at some point, the HTC will experience a patient incarcerated for some period of time. The HTC will continue to advocate for their patient within this system, despite the many challenges faced. Despite the challenges outlined, ongoing communication and education with the correctional system, education of the medical personnel and prison personnel remains the priority as we advocate for our patients. Continued strategies in these areas are paramount. © 2015 John Wiley & Sons Ltd.

Total Organic Carbon Distribution and Bacterial Cycling Across A Geostrophic Front In Mediterranean Sea. Implications For The Western Basin Carbon Cycle

NASA Astrophysics Data System (ADS)

Sempere, R.; van Wambeke, F.; Bianchi, M.; Dafner, E.; Lefevre, D.; Bruyant, F.; Prieur, L.

We investigated the dynamic of the total organic carbon (TOC) pool and the role it played in the carbon cycle during winter 1997-1998 in the Almeria-Oran jet-front (AOF) system resulting from the spreading of Atlantic surface water through the Gibraltar Strait in the Alboran Sea (Southwestern Mediterranean Sea). We determined TOC by using high temperature combustion technique (HTC) and bacterial produc- tion (BP; via [3H] leucine incorporation) during two legs in the frontal area. We also estimated labile TOC (l-TOC) and bacterial growth efficiency (BGE) by performing TOC biodegradation experiments on board during the cruise whereas water column semi-labile (sl-TOC), and refractory-TOC were determined from TOC profile exami- nation. These results are discussed in relation with current velocity measured by using accoustic doppler current profiler (ADCP). Lowest TOC stocks (6330-6853 mmol C m-2) over 0-100 m were measured in the northern side of the geostrophic Jet which is also the highest dynamic area (horizontal speed of 80 cm s-1 in the first 100 m di- rected eastward). Our results indicated variable turnover times of sl-TOC across the Jet-Front system, which might be explained by different coupling of primary produc- tion and bacterial production observed in these areas. We also estimated TOC and sl-TOC transports within the Jet core off the Alboran Sea as well as potential CO2 production through bacterial respiration produced from sl-TOC assimilation by het- erotrophic bacteria.

Functionalization of biomass carbonaceous aerogels: selective preparation of MnO2@CA composites for supercapacitors.

PubMed

Ren, Yumei; Xu, Qun; Zhang, Jianmin; Yang, Hongxia; Wang, Bo; Yang, Daoyuan; Hu, Junhua; Liu, Zhimin

2014-06-25

Functionalized porous carbon materials with hierarchical structure and developed porosity coming from natural and renewable biomass have been attracting tremendous attention recently. In this work, we present a facile and scalable method to synthesize MnO2 loaded carbonaceous aerogel (MnO2@CA) composites via the hydrothermal carbonaceous (HTC) process. We employ two reaction systems of the mixed metal ion precursors to study the optimal selective adsorption and further reaction of MnO2 precursor on CA. Our experimental results show that the system containing KMnO4 and Na2S2O3·5H2O exhibits better electrochemical properties compared with the reaction system of MnSO4·H2O and (NH4)2S2O8. For the former, the obtained MnO2@CA displays the specific capacitance of 123.5 F·g(-1). The enhanced supercapacitance of MnO2@CA nanocomposites could be ascribed to both electrochemical contributions of the loaded MnO2 nanoparticles and the porous structure of three-dimensional carbonaceous aerogels. This study not only indicates that it is vital for the reaction systems to match with porous carbonaceous materials, but also offers a new fabrication strategy to prepare lightweight and high-performance materials that can be used in energy storage devices.

Effect of Processing, Post-Harvest Irradiation, and Production System on the Cytotoxicity and Mutagenicity of Vitis labrusca L. Juices in HTC Cells

PubMed Central

Düsman, Elisângela; de Almeida, Igor Vivian; Lucchetta, Luciano; Vicentini, Veronica Elisa Pimenta

2014-01-01

The juices of grapes (Vitis labrusca L.) are similar to the fruit itself because the main constituents of the fruit are present in the juice. However, their quality characteristics may be modified by the harsh technological processes used for the production of integral food, such as production systems of raw materials and post-harvest treatment of grapes with ultraviolet (UV) irradiation. Therefore, the present study analyzed juices produced naturally (by liquefying the fruit) or by the technological process of extraction by steam distillation (90°C) of grapes from organic and conventional production systems that were untreated or treated with UV type C (65.6 J/m2 for 10 minutes). Using cultures of Rattus norvegicus hepatoma cells (HTC) in vitro, cytotoxic effects were assayed by the MTT test and by calculating the cytokinesis blocked proliferation index (CBPI), and mutagenic effects were measured by the cytokinesis block micronucleus assay. The results of the MTT assay and the CBPIs indicated that none of the juices were cytotoxic, including those that induced cell proliferation. The results of the micronucleus assay showed that none of the juices were mutagenic. However, the average number of micronuclei was lower in the juices produced from organic grapes, and cell proliferation, soluble acids and phenolic compounds were significantly higher. Compared with the natural juices, the integral juices of conventional grapes showed a higher average number of micronuclei as well as lower stimulation of cell proliferation and lower levels of bioactive compounds. The results demonstrate a beneficial effect of UV-C irradiation of post-harvest grapes in stimulating the synthesis of nutraceutical compounds without generating cytotoxic or mutagenic substances. Taken together, our findings support the consumption of grape juice and the application of food production techniques that enhance its nutritional value and promote its production, marketing and consumption. PMID:25244067

Effect of processing, post-harvest irradiation, and production system on the cytotoxicity and mutagenicity of Vitis labrusca L. juices in HTC cells.

PubMed

Düsman, Elisângela; de Almeida, Igor Vivian; Lucchetta, Luciano; Vicentini, Veronica Elisa Pimenta

2014-01-01

The juices of grapes (Vitis labrusca L.) are similar to the fruit itself because the main constituents of the fruit are present in the juice. However, their quality characteristics may be modified by the harsh technological processes used for the production of integral food, such as production systems of raw materials and post-harvest treatment of grapes with ultraviolet (UV) irradiation. Therefore, the present study analyzed juices produced naturally (by liquefying the fruit) or by the technological process of extraction by steam distillation (90°C) of grapes from organic and conventional production systems that were untreated or treated with UV type C (65.6 J/m² for 10 minutes). Using cultures of Rattus norvegicus hepatoma cells (HTC) in vitro, cytotoxic effects were assayed by the MTT test and by calculating the cytokinesis blocked proliferation index (CBPI), and mutagenic effects were measured by the cytokinesis block micronucleus assay. The results of the MTT assay and the CBPIs indicated that none of the juices were cytotoxic, including those that induced cell proliferation. The results of the micronucleus assay showed that none of the juices were mutagenic. However, the average number of micronuclei was lower in the juices produced from organic grapes, and cell proliferation, soluble acids and phenolic compounds were significantly higher. Compared with the natural juices, the integral juices of conventional grapes showed a higher average number of micronuclei as well as lower stimulation of cell proliferation and lower levels of bioactive compounds. The results demonstrate a beneficial effect of UV-C irradiation of post-harvest grapes in stimulating the synthesis of nutraceutical compounds without generating cytotoxic or mutagenic substances. Taken together, our findings support the consumption of grape juice and the application of food production techniques that enhance its nutritional value and promote its production, marketing and consumption.

Modeling physical vapor deposition of energetic materials

DOE PAGES

Shirvan, Koroush; Forrest, Eric C.

2018-03-28

Morphology and microstructure of organic explosive films formed using physical vapor deposition (PVD) processes strongly depends on local surface temperature during deposition. Currently, there is no accurate means of quantifying the local surface temperature during PVD processes in the deposition chambers. This study focuses on using a multiphysics computational fluid dynamics tool, STARCCM+, to simulate pentaerythritol tetranitrate (PETN) deposition. The PETN vapor and solid phase were simulated using the volume of fluid method and its deposition in the vacuum chamber on spinning silicon wafers was modeled. The model also included the spinning copper cooling block where the wafers are placedmore » along with the chiller operating with forced convection refrigerant. Implicit time-dependent simulations in two- and three-dimensional were performed to derive insights in the governing physics for PETN thin film formation. PETN is deposited at the rate of 14 nm/s at 142.9 °C on a wafer with an initial temperature of 22 °C. The deposition of PETN on the wafers was calculated at an assumed heat transfer coefficient (HTC) of 400 W/m 2 K. This HTC proved to be the most sensitive parameter in determining the local surface temperature during deposition. Previous experimental work found noticeable microstructural changes with 0.5 mm fused silica wafers in place of silicon during the PETN deposition. This work showed that fused silica slows initial wafer cool down and results in ~10 °C difference for the surface temperature at 500 μm PETN film thickness. It was also found that the deposition surface temperature is insensitive to the cooling power of the copper block due to the copper block's very large heat capacity and thermal conductivity relative to the heat input from the PVD process. Future work should incorporate the addition of local stress during PETN deposition. Lastly, based on simulation results, it is also recommended to investigate the impact of wafer surface energy on the PETN microstructure and morphology formation.« less

Modeling physical vapor deposition of energetic materials

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

Shirvan, Koroush; Forrest, Eric C.

Morphology and microstructure of organic explosive films formed using physical vapor deposition (PVD) processes strongly depends on local surface temperature during deposition. Currently, there is no accurate means of quantifying the local surface temperature during PVD processes in the deposition chambers. This study focuses on using a multiphysics computational fluid dynamics tool, STARCCM+, to simulate pentaerythritol tetranitrate (PETN) deposition. The PETN vapor and solid phase were simulated using the volume of fluid method and its deposition in the vacuum chamber on spinning silicon wafers was modeled. The model also included the spinning copper cooling block where the wafers are placedmore » along with the chiller operating with forced convection refrigerant. Implicit time-dependent simulations in two- and three-dimensional were performed to derive insights in the governing physics for PETN thin film formation. PETN is deposited at the rate of 14 nm/s at 142.9 °C on a wafer with an initial temperature of 22 °C. The deposition of PETN on the wafers was calculated at an assumed heat transfer coefficient (HTC) of 400 W/m 2 K. This HTC proved to be the most sensitive parameter in determining the local surface temperature during deposition. Previous experimental work found noticeable microstructural changes with 0.5 mm fused silica wafers in place of silicon during the PETN deposition. This work showed that fused silica slows initial wafer cool down and results in ~10 °C difference for the surface temperature at 500 μm PETN film thickness. It was also found that the deposition surface temperature is insensitive to the cooling power of the copper block due to the copper block's very large heat capacity and thermal conductivity relative to the heat input from the PVD process. Future work should incorporate the addition of local stress during PETN deposition. Lastly, based on simulation results, it is also recommended to investigate the impact of wafer surface energy on the PETN microstructure and morphology formation.« less

Persons with Haemophilia in Sweden- Experiences and Strategies in Everyday Life. A Single Centre Study

PubMed Central

2015-01-01

Introduction/Aim Haemophilia is caused by deficiency in coagulation factor VIII or IX. Treatment with the missing coagulation factors has been available in most developed countries for several decades. The aim was to explore the experiences of adults living with severe or moderate haemophilia and their coping strategies at a single centre in Sweden. Method The interview study had a qualitative empirical approach and was analyzed on the basis of the method empirical phenomenological psychology. The sample included 14 participants, mean age 42 (19–80 y), who met the inclusion criteria and to saturation of information. Results: General characteristics were; All were satisfied with and grateful for access to medication. An acceptance of the disorder and willingness to live a normal life was identified among all participants. They were all content with the care provided by Haemophilia Treatment Centre (HTC) and felt supported by its multidisciplinary team. Four typologies were identified; Protective adults and assertive children during up-bringing, finding a role in social context, symptoms and treatments, fear of limited resources in the future. Task-, emotional- and avoidance coping strategies were seen in the interviews. The most prominent coping strategy was task oriented. Conclusion This interview study with Swedish PWH shows that they strive for normality and adaptation in social activities throughout life finding their own niche. The PWH expressed the importance of knowledge and support from the comprehensive medical team at HTC and therefore it seems important to continue comprehensive medical care at HTC in order to follow-up the haemophilia persons regularly. PMID:26431432

The Open Science Grid - Support for Multi-Disciplinary Team Science - the Adolescent Years

NASA Astrophysics Data System (ADS)

Bauerdick, Lothar; Ernst, Michael; Fraser, Dan; Livny, Miron; Pordes, Ruth; Sehgal, Chander; Würthwein, Frank; Open Science Grid

2012-12-01

As it enters adolescence the Open Science Grid (OSG) is bringing a maturing fabric of Distributed High Throughput Computing (DHTC) services that supports an expanding HEP community to an increasingly diverse spectrum of domain scientists. Working closely with researchers on campuses throughout the US and in collaboration with national cyberinfrastructure initiatives, we transform their computing environment through new concepts, advanced tools and deep experience. We discuss examples of these including: the pilot-job overlay concepts and technologies now in use throughout OSG and delivering 1.4 Million CPU hours/day; the role of campus infrastructures- built out from concepts of sharing across multiple local faculty clusters (made good use of already by many of the HEP Tier-2 sites in the US); the work towards the use of clouds and access to high throughput parallel (multi-core and GPU) compute resources; and the progress we are making towards meeting the data management and access needs of non-HEP communities with general tools derived from the experience of the parochial tools in HEP (integration of Globus Online, prototyping with IRODS, investigations into Wide Area Lustre). We will also review our activities and experiences as HTC Service Provider to the recently awarded NSF XD XSEDE project, the evolution of the US NSF TeraGrid project, and how we are extending the reach of HTC through this activity to the increasingly broad national cyberinfrastructure. We believe that a coordinated view of the HPC and HTC resources in the US will further expand their impact on scientific discovery.

Hard-to-cook bean (Phaseolus vulgaris L.) proteins hydrolyzed by alcalase and bromelain produced bioactive peptide fractions that inhibit targets of type-2 diabetes and oxidative stress.

PubMed

Oseguera-Toledo, Miguel E; Gonzalez de Mejia, Elvira; Amaya-Llano, Silvia L

2015-10-01

The objective was to evaluate the effect of bioactive peptide fractions from de-hulled hard-to-cook (HTC) bean on enzyme targets of type-2 diabetes and oxidative stress. Protein isolates from Pinto Durango and Negro 8025 beans were hydrolyzed (120min) with either alcalase® or bromelain and separated into five peptide fractions (<1, 1-3.5, 3.5-5, 5-10, and >10kDa) using an ultrafiltration membrane system. The <1kDa pinto Durango-bromelain fraction showed the best inhibition of α-amylase (49.9±1.4%), and the <1kDa pinto Durango-alcalase fraction inhibited both, α-glucosidase (76.4±0.5%), and dipeptidyl peptidase-IV (DPP-IV, 55.3±1.6%). Peptides LLSL, QQEG and NEGEAH were present in the most potent fractions. Hydrolysates and peptide fractions showed antioxidant capacity (ORAC: 159.6±2.9 to 932.6±1.1mmolTE/g) and nitric oxide inhibition (57.5±0.9 to 68.3±4.2%). Hydrolysates and fractions <1 and 1-3kDa were able to increase glucose-stimulated insulin secretion from iNS-1E cells up to 57% compared to glucose control. Hydrolysates from HTC beans inhibited enzymes related to diabetes management, being the smallest peptides (<1kDa) the most potent. HTC bean could be a source of protein to produce bioactive peptides with potential antidiabetic properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sewage sludge hydrochars: properties and agronomic impact as related to different production conditions

NASA Astrophysics Data System (ADS)

Paneque, Marina; María De la Rosa, José; Aragón, Carlos; Kern, Jürgen; Conte, Pellegrino; Knicker, Heike

2015-04-01

The huge amount of sewage sludge (SS) generated in wastewater treatment plants all over the world represents an environmental problem. Due to the high concentration of phosphorus and nitrogen in SS as well as other macro and micro nutrients it has been considered a suitable soil amendment. However, before being applied to soil a complete sterilization and elimination of pollutants should be carried out [1]. In this context, thermal treatments appear as a convenient methodology for producing SS byproducts useful for agronomic purposes. Hydrothermal carbonization (HTC) is a kind of pyrolysis characterized by the heating of the biomass in presence of water. This process shows an advantage compared to other thermal treatments for wet residues since dryness of the biomass prior to the thermal transformation is not necessary. The solid product which results from HTC is called hydrochar and it has been suggested to increase soil productivity [2]. However, the agronomic potential of hydrochars depends on the feedstock and production conditions. Additionally, possible toxic and risks have to be carefully evaluated. Thus, SS hydrochars appear as a potential soil amendment but further scientific research is needed to find its real capacity, optimal production conditions as well as possible environmental harmful effects. The aim of this study was to evaluate which are the most suitable production conditions, to transform SS into hydrochar. An additional goal of this work was to relate the hydrochars properties to its agronomic response. Therefore, hydrochars were produced from SS collected from the Experimental Wastewater Treatment plant of CENTA (http://www.centa.es/), located in Carrion de los Cespedes (Seville), under two different temperatures (200 and 260˚C) and residence times (30 min and 1h). With the hydrochars obtained, a greenhouse pot incubation study was carried out for 80 days. The pots contained 250 g of a Calcic Cambisol (IUSS Working Group WRB, 2007) and an amount of hydrochar equivalent to 5 and 25 t ha-1 were prepared in quadruplicate for each hydrochar using Lolium perenne as test plant (25 seeds per pot). Hydrochars were not washed before this experiment. Control pots, without hydrochar amendment, were also settled for comparison purposes (n=6). After adjusting the soil humidity to 60% of the maximum WHC, the pots were placed into a greenhouse under similar conditions than those reported by [3]. In this experiment germination, survival rates and biomass production per pot were measured periodically. Elemental analysis and the determination of several chemical properties of hydrochars such as pH, electrical conductivity and ash content were performed. Additionally, 13C solid-state nuclear magnetic resonance (NMR) was applied to elucidate the main chemical groups whereas fast field cycling (FFC) NMR relaxometry was valuable for investigating the porous structure and water dynamic in the different hydrochars. This work confirmed that production conditions of hydrochars vary their chemical properties and hence their agronomic effect. Biomass production raised significantly in presence of all hydrochars, being the response in presence of hydrochars produced at 200˚C significantly higher than the response in presence of hydrochars produced at 260˚C, whereas the residence time of the hydrochars in the reactor did not affect biomass productivity. Concerning the characterization data, hydrochars which showed the highest biomass production were those which contain the highest mineralized nitrogen content (NH4, NO2 and NO3) and a greater presence of alkyl carbons and carboxyl groups. Hydrochars FFC NMR relaxometry results show a lower T1 (longitudinal relaxation time) compared to the pure sewage sludge, which suggests that HTC processes reduced the average pore size of the system. This has further implications in the water and nutrient retention capacity of the hydrochars compared to the pure sewage sludge. Acknowledgements: The Marie Sklodowska-Curie actions of the EU 7th Framework People Programme (REA grant agreement PCIG12-GA-2012-333784-Biocharisma project) and the Spanish Ministry of Economy and Competitiveness (MINECO) (project PCGL2012-37041) are thanked for the financial support of the present study. The CSIC and the European Social Fund (ESF) are thanked for funding J.M. de la Rosa JAE-Doc contract. MINECO Spanish Ministry is thanked for funding the FPU fellowship (FPU 13/05831) of Marina Paneque. References: [1] Fytili D. and Zabaniotou A. (2008) Energy Reviews. 12, 116-140 [2] Libra JA, Ro KS, Kammann C, Funke A, Berge ND, Neubauer Y, Titirici MM, Fühner C, Bens O, Kern J, Emmerich KH (2011) Biofuels. 2, 89-124. [3] De la Rosa, Paneque M, Miller AZ, Knicker H (2014) Science of the Total Environment. 499, 175-184.

A review on hydrothermal pre-treatment technologies and environmental profiles of algal biomass processing.

PubMed

Patel, Bhavish; Guo, Miao; Izadpanah, Arash; Shah, Nilay; Hellgardt, Klaus

2016-01-01

The need for efficient and clean biomass conversion technologies has propelled Hydrothermal (HT) processing as a promising treatment option for biofuel production. This manuscript discussed its application for pre-treatment of microalgae biomass to solid (biochar), liquid (biocrude and biodiesel) and gaseous (hydrogen and methane) products via Hydrothermal Carbonisation (HTC), Hydrothermal Liquefaction (HTL) and Supercritical Water Gasification (SCWG) as well as the utility of HT water as an extraction medium and HT Hydrotreatment (HDT) of algal biocrude. In addition, the Solar Energy Retained in Fuel (SERF) using HT technologies is calculated and compared with benchmark biofuel. Lastly, the Life Cycle Assessment (LCA) discusses the limitation of the current state of art as well as introduction to new potential input categories to obtain a detailed environmental profile. Copyright © 2015 Elsevier Ltd. All rights reserved.

HIV prevention costs and their predictors: evidence from the ORPHEA Project in Kenya

PubMed Central

Galárraga, Omar; Wamai, Richard G; Sosa-Rubí, Sandra G; Mugo, Mercy G; Contreras-Loya, David; Bautista-Arredondo, Sergio; Nyakundi, Helen; Wang’ombe, Joseph K

2017-01-01

Abstract We estimate costs and their predictors for three HIV prevention interventions in Kenya: HIV testing and counselling (HTC), prevention of mother-to-child transmission (PMTCT) and voluntary medical male circumcision (VMMC). As part of the ‘Optimizing the Response of Prevention: HIV Efficiency in Africa’ (ORPHEA) project, we collected retrospective data from government and non-governmental health facilities for 2011–12. We used multi-stage sampling to determine a sample of health facilities by type, ownership, size and interventions offered totalling 144 sites in 78 health facilities in 33 districts across Kenya. Data sources included key informants, registers and time-motion observation methods. Total costs of production were computed using both quantity and unit price of each input. Average cost was estimated by dividing total cost per intervention by number of clients accessing the intervention. Multivariate regression methods were used to analyse predictors of log-transformed average costs. Average costs were $7 and $79 per HTC and PMTCT client tested, respectively; and $66 per VMMC procedure. Results show evidence of economies of scale for PMTCT and VMMC: increasing the number of clients per year by 100% was associated with cost reductions of 50% for PMTCT, and 45% for VMMC. Task shifting was associated with reduced costs for both PMTCT (59%) and VMMC (54%). Costs in hospitals were higher for PMTCT (56%) in comparison to non-hospitals. Facilities that performed testing based on risk factors as opposed to universal screening had higher HTC average costs (79%). Lower VMMC costs were associated with availability of male reproductive health services (59%) and presence of community advisory board (52%). Aside from increasing production scale, HIV prevention costs may be contained by using task shifting, non-hospital sites, service integration and community supervision. PMID:29029086

Operational feasibility of using whole blood in the rapid HIV testing algorithm of a resource-limited settings like Bangladesh.

PubMed

Munshi, Saif U; Oyewale, Tajudeen O; Begum, Shahnaz; Uddin, Ziya; Tabassum, Shahina

2016-03-01

Serum-based rapid HIV testing algorithm in Bangladesh constitutes operational challenge to scaleup HIV testing and counselling (HTC) in the country. This study explored the operational feasibility of using whole blood as alternative to serum for rapid HIV testing in Bangladesh. Whole blood specimens were collected from two study groups. The groups included HIV-positive patients (n = 200) and HIV-negative individuals (n = 200) presenting at the reference laboratory in Dhaka, Bangladesh. The specimens were subjected to rapid HIV tests using the national algorithm with A1 = Alere Determine (United States), A2 = Uni-Gold (Ireland), and A3 = First Response (India). The sensitivity and specificity of the test results, and the operational cost were compared with current serum-based testing. The sensitivities [95% of confidence interval (CI)] for A1, A2, and A3 tests using whole blood were 100% (CI: 99.1-100%), 100% (CI: 99.1-100%), and 97% (CI: 96.4-98.2%), respectively, and specificities of all test kits were 100% (CI: 99.1-100%). Significant (P < 0.05) reduction in the cost of establishing HTC centre and consumables by 94 and 61%, respectively, were observed. The cost of administration and external quality assurance reduced by 39 and 43%, respectively. Overall, there was a 36% cost reduction in total operational cost of rapid HIV testing with blood when compared with serum. Considering the similar sensitivity and specificity of the two specimens, and significant cost reduction, rapid HIV testing with whole blood is feasible. A review of the national HIV rapid testing algorithm with whole blood will contribute toward improving HTC coverage in Bangladesh.

The experience of being a female carrier of haemophilia and the mother of a haemophilic child.

PubMed

Myrin-Westesson, L; Baghaei, F; Friberg, F

2013-03-01

Limited research has been conducted on how the female carrier experiences her life with a haemophilic child, and earlier studies are mostly questionnaire-based. No previous qualitative study on the female carrier's situation has been conducted in Sweden. The aim of the study was to describe the lived experience of being a carrier of severe or moderate haemophilia and of being the mother of a haemophilic child. The study was conducted via qualitative interviews and analysed by means of a phenomenological hermeneutic method; a total of 13 haemophilia carriers were interviewed in 2010. Being a carrier of haemophilia and having a haemophilic child was life changing. The women moved from a state of sad, guilty chaos to reconciling themselves with the new situation. Our analysis revealed three acts in which phenomena appeared: the time after diagnosis, the turning point and reconciliation with a changing life. Emerging as crucial to the process of reconciliation with a changing life was a sense of being fully informed and supported. The Haemophilia Treatment Centre (HTC) should create an environment that encourages learning, and the team should invite and encourage the woman's partner to be actively involved in the child's care. Moreover, the results indicate that it would be beneficial to invite female carriers to receive patient education at the HTC before they plan to start a family. During this visit, the woman may gain a greater understanding of her carriership to prepare her for future decisions concerning prenatal diagnosis, for example. © 2012 Blackwell Publishing Ltd.

Efficiency gain limits of the parallel segmented inlet and outlet flow concept in analytical liquid chromatography columns suffering from radial transcolumn packing density gradients.

PubMed

Broeckhoven, Ken; Desmet, Gert

2012-10-05

The maximal gain in efficiency that can be expected from the use of the segmented column end fittings that were recently introduced to alleviate the effect of transcolumn packing density gradients has been quantified and generalized using numerical computations of the band broadening process. It was found that, for an unretained compound in a column with a parabolic packing density gradient, the use of a segmented inlet or a segmented outlet allows to eliminate about 60-100% of the plate height contribution (H(tc)) originating from a parabolic transcolumn velocity gradient in a d(c)=4.6 mm column. In a d(c)=2.1 mm column, these percentages change from 10 to 100%. Using a combined segmented in- and outlet, H(tc) can be reduced by about 90-100% (d(c)=4.6 mm column) or 20-100% (d(c)=2.1 mm column). The strong variation of these gain percentages is due to fact that they depend very strongly on the column length and the flow rate. Dimensionless graphs have been established that allow to directly quantify the effect for each specific case. It was also found that, in agreement with one's physical intuition, trans-column velocity profiles that are more flat in the central region benefit more from the concept than sharp, parabolic-like profiles. The gain margins furthermore tend to become smaller with increasing retention and increasing diffusion coefficient. Copyright © 2012 Elsevier B.V. All rights reserved.

Analysis of electric current flow through the HTc multilayered superconductors

NASA Astrophysics Data System (ADS)

Sosnowski, J.

2016-02-01

Issue of the flow of the transport current through multilayered high-temperature superconductors is considered, depending on the direction of the electric current towards the surface of the superconducting CuO2 layers. For configuration of the current flow inside of the layers and for perpendicular magnetic field, it will be considered the current limitations connected with interaction of pancake type vortices with nano-sized defects, created among other during fast neutrons irradiation. So it makes this issue associated with work of nuclear energy devices, like tokamak ITER, LHC and actually developed accelerator Nuclotron-NICA, as well as cryocables. Phenomenological analysis of the pinning potential barrier formation will be in the paper given, which determines critical current flow inside the plane. Comparison of theoretical model with experimental data will be presented too as well as influence of fast neutrons irradiation dose on critical current calculated. For current direction perpendicular to superconducting planes the current-voltage characteristics are calculated basing on model assuming formation of long intrinsic Josephson's junctions in layered HTc superconductors.

An Improved Method of Pose Estimation for Lighthouse Base Station Extension.

PubMed

Yang, Yi; Weng, Dongdong; Li, Dong; Xun, Hang

2017-10-22

In 2015, HTC and Valve launched a virtual reality headset empowered with Lighthouse, the cutting-edge space positioning technology. Although Lighthouse is superior in terms of accuracy, latency and refresh rate, its algorithms do not support base station expansion, and is flawed concerning occlusion in moving targets, that is, it is unable to calculate their poses with a small set of sensors, resulting in the loss of optical tracking data. In view of these problems, this paper proposes an improved pose estimation algorithm for cases where occlusion is involved. Our algorithm calculates the pose of a given object with a unified dataset comprising of inputs from sensors recognized by all base stations, as long as three or more sensors detect a signal in total, no matter from which base station. To verify our algorithm, HTC official base stations and autonomous developed receivers are used for prototyping. The experiment result shows that our pose calculation algorithm can achieve precise positioning when a few sensors detect the signal.

An Improved Method of Pose Estimation for Lighthouse Base Station Extension

PubMed Central

Yang, Yi; Weng, Dongdong; Li, Dong; Xun, Hang

2017-01-01

In 2015, HTC and Valve launched a virtual reality headset empowered with Lighthouse, the cutting-edge space positioning technology. Although Lighthouse is superior in terms of accuracy, latency and refresh rate, its algorithms do not support base station expansion, and is flawed concerning occlusion in moving targets, that is, it is unable to calculate their poses with a small set of sensors, resulting in the loss of optical tracking data. In view of these problems, this paper proposes an improved pose estimation algorithm for cases where occlusion is involved. Our algorithm calculates the pose of a given object with a unified dataset comprising of inputs from sensors recognized by all base stations, as long as three or more sensors detect a signal in total, no matter from which base station. To verify our algorithm, HTC official base stations and autonomous developed receivers are used for prototyping. The experiment result shows that our pose calculation algorithm can achieve precise positioning when a few sensors detect the signal. PMID:29065509

Nano-inspired fluidic interactivity for boiling heat transfer: impact and criteria

PubMed Central

Kim, Beom Seok; Choi, Geehong; Shin, Sangwoo; Gemming, Thomas; Cho, Hyung Hee

2016-01-01

The enhancement of boiling heat transfer, the most powerful energy-transferring technology, will lead to milestones in the development of high-efficiency, next-generation energy systems. Perceiving nano-inspired interface functionalities from their rough morphologies, we demonstrate interface-induced liquid refreshing is essential to improve heat transfer by intrinsically avoiding Leidenfrost phenomenon. High liquid accessibility of hemi-wicking and catalytic nucleation, triggered by the morphological and hydrodynamic peculiarities of nano-inspired interfaces, contribute to the critical heat flux (CHF) and the heat transfer coefficient (HTC). Our experiments show CHF is a function of universal hydrodynamic characteristics involving interfacial liquid accessibility and HTC is improved with a higher probability of smaller nuclei with less superheat. Considering the interface-induced and bulk liquid accessibility at boiling, we discuss functionalizing the interactivity between an interface and a counteracting fluid seeking to create a novel interface, a so-called smart interface, for a breakthrough in boiling and its pragmatic application in energy systems. PMID:27708341

Portable Low-Volume Therapy for Severe Blood Loss

DTIC Science & Technology

2012-06-01

be reflected in Htc as well. Classic changes in plasma electrolyte concentration during hemorrhagic shock include hyperkalemia [17, 18] and...comparison with treatment no. 1 (pɘ.05), treatment no. 2 (pɘ.05), and treatment no. 3 (pɘ.05). Because the hyperkalemia and hyponatremia in

Sensitivity Analysis of Fuel Centerline Temperatures in SuperCritical Water-cooled Reactors (SCWRs)

NASA Astrophysics Data System (ADS)

Abdalla, Ayman

SuperCritical Water-cooled Reactors (SCWRs) are one of the six nuclear-reactor concepts currently being developed under the Generation-IV International Forum (GIF). A main advantage of SCW Nuclear Power Plants (NPPs) is that they offer higher thermal efficiencies compared to those of current conventional NPPs. Unlike today's conventional NPPs, which have thermal efficiencies between 30 - 35%, SCW NPPs will have thermal efficiencies within a range of 45 - 50%, owing to high operating temperatures and pressures (i.e., coolant temperatures as high as 625°C at 25 MPa pressure). The use of current fuel bundles with UO2 fuel at the high operating parameters of SCWRs may cause high fuel centerline temperatures, which could lead to fuel failure and fission gas release. Studies have shown that when the Variant-20 (43-element) fuel bundle was examined at SCW conditions, the fuel centerline temperature industry limit of 1850°C for UO2 and the sheath temperature design limit of 850°C might be exceeded. Therefore, new fuel-bundle designs, which comply with the design requirements, are required for future use in SCWRs. The main objective of this study to conduct a sensitivity analysis in order to identify the main factors that leads to fuel centerline temperature reduction. Therefore, a 54-element fuel bundle with smaller diameter of fuel elements compared to that of the 43-element bundle was designed and various nuclear fuels are examined for future use in a generic Pressure Tube (PT) SCWR. The 54-element bundle consists of 53 heated fuel elements with an outer diameter of 9.5 mm and one central unheated element of 20-mm outer diameter which contains burnable poison. The 54-element fuel bundle has an outer diameter of 103.45 mm, which is the same as the outer diameter of the 43-element fuel bundle. After developing the 54-element fuel bundle, one-dimensional heat-transfer analysis was conducted using MATLAB and NIST REFPROP programs. As a result, the Heat Transfer Coefficient (HTC), bulk-fluid, sheath and fuel centerline temperature profiles were generated along the heated length of 5.772 m for a generic fuel channel. The fuel centerline and sheath temperature profiles have been determined at four Axial Heat Flux Profiles (AHFPs) using an average thermal power per channel of 8.5 MWth. The four examined AHFPs are the uniform, cosine, upstream-skewed and downstream-skewed profiles. Additionally, this study focuses on investigating a possibility of using low, enhanced and high thermal-conductivity fuels. The low thermal-conductivity fuels, which have been examined in this study, are uranium dioxide (UO 2), Mixed Oxide (MOX) and Thoria (ThO2) fuels. The examined enhanced thermal-conductivity fuels are uranium dioxide - silicon carbide (UO2 - SiC) and uranium dioxide - beryllium oxide (UO2 - BeO). Lastly, uranium carbide (UC), uranium dicarbide (UC2) and uranium nitride (UN) are the selected high thermal-conductivity fuels, which have been proposed for use in SCWRs. A comparison has been made between the low, enhanced and high thermal-conductivity fuels in order to identify the fuel centerline temperature behaviour when different nuclear fuels are used. Also, in the process of conducting the sensitivity analysis, the HTC was calculated using the Mokry et al. correlation, which is the most accurate supercritical water heat-transfer correlation so far. The sheath and the fuel centerline temperature profiles were determined for two cases. In Case 1, the HTC was calculated based on the Mokry et al. correlation, while in Case 2, the HTC values calculated for Case 1 were multiplied by a factor of 2. This factor was used in order to identify the amount of decrease in temperatures if the heat transfer is enhanced with appendages. Results of this analysis indicate that the use of the newly developed 54-element fuel bundle along with the proposed fuels is promising when compared with the Variant-20 (43-element) fuel bundle. Overall, the fuel centerline and sheath temperatures were below the industry and design limits when most of the proposed fuels were examined in the 54-element fuel bundle, however, the fuel centerline temperature limit was exceeded while MOX fuel was examined. Keywords: SCWRs, Fuel Centerline Temperature, Sheath Temperature, High Thermal Conductivity Fuels, Low Thermal Conductivity Fuels, HTC.

Investigation into the use of smartphone as a machine vision device for engineering metrology and flaw detection, with focus on drilling

NASA Astrophysics Data System (ADS)

Razdan, Vikram; Bateman, Richard

2015-05-01

This study investigates the use of a Smartphone and its camera vision capabilities in Engineering metrology and flaw detection, with a view to develop a low cost alternative to Machine vision systems which are out of range for small scale manufacturers. A Smartphone has to provide a similar level of accuracy as Machine Vision devices like Smart cameras. The objective set out was to develop an App on an Android Smartphone, incorporating advanced Computer vision algorithms written in java code. The App could then be used for recording measurements of Twist Drill bits and hole geometry, and analysing the results for accuracy. A detailed literature review was carried out for in-depth study of Machine vision systems and their capabilities, including a comparison between the HTC One X Android Smartphone and the Teledyne Dalsa BOA Smart camera. A review of the existing metrology Apps in the market was also undertaken. In addition, the drilling operation was evaluated to establish key measurement parameters of a twist Drill bit, especially flank wear and diameter. The methodology covers software development of the Android App, including the use of image processing algorithms like Gaussian Blur, Sobel and Canny available from OpenCV software library, as well as designing and developing the experimental set-up for carrying out the measurements. The results obtained from the experimental set-up were analysed for geometry of Twist Drill bits and holes, including diametrical measurements and flaw detection. The results show that Smartphones like the HTC One X have the processing power and the camera capability to carry out metrological tasks, although dimensional accuracy achievable from the Smartphone App is below the level provided by Machine vision devices like Smart cameras. A Smartphone with mechanical attachments, capable of image processing and having a reasonable level of accuracy in dimensional measurement, has the potential to become a handy low-cost Machine vision system for small scale manufacturers, especially in field metrology and flaw detection.

78 FR 13673 - HTC America, Inc.; Analysis of Proposed Consent Order To Aid Public Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-28

... modifying various pre-installed applications and components in order to differentiate its products from.... As the customized applications and components are pre-installed on the device, consumers do not... together, failed to provide reasonable and appropriate security in the design and customization of software...

D.R.E.A.M.S: (Digital Rehabilitation Environment-Altering Medical System).

PubMed

Suvajdzic, Marko; Bihorac, Azra; Rashidi, Parisa

2017-04-01

In project D.R.E.A.M.S., we propose to develop and assess the feasibility of a novel and intelligent delirium-prevention system to address depression, pain, sleep, activity patterns and emotional states using the Emotiv Epoc+ I 14 Channel EEG", and HTC Vive VR set.

Effect of sewage sludge hydrochar on soil properties and Cd immobilization in a contaminated soil.

PubMed

Ren, Jie; Wang, Fenghua; Zhai, Yunbo; Zhu, Yun; Peng, Chuan; Wang, Tengfei; Li, Caiting; Zeng, Guangming

2017-12-01

To investigate hydrochar as a soil amendment for the immobilization of Cd, the characteristics of hydrochars (HCs) under three temperatures and residence times, were studied, with a particular interest in soil properties, as well as the speciation, availability and plant uptake of Cd. HCs were obtained by a hydrothermal carbonization (HTC) reaction of sewage sludge (SS). Based on the study of HC properties, we found that HCs present weak acidity with relatively high ash content and low electrical conductivity (EC) values. The addition of HCs to soil decreased soil pH and EC values but increased the abundance of soil microorganism. HCs also promoted the transformation of Cd from unstable to stable speciation and can decrease the content of phyto-available Cd (optimum condition and efficiency: A13, 2 15.38%), which restrained cabbage from assimilating Cd from soil both the aboveground (optimum condition and efficiency: A35, 52.29%) and underground (optimum condition and efficiency: C15, 57.53%) parts of it. Copyright © 2017 Elsevier Ltd. All rights reserved.

A comparison of product yields and inorganic content in process streams following thermal hydrolysis and hydrothermal processing of microalgae, manure and digestate.

PubMed

Ekpo, U; Ross, A B; Camargo-Valero, M A; Williams, P T

2016-01-01

Thermal hydrolysis and hydrothermal processing show promise for converting biomass into higher energy density fuels. Both approaches facilitate the extraction of inorganics into the aqueous product. This study compares the behaviour of microalgae, digestate, swine and chicken manure by thermal hydrolysis and hydrothermal processing at increasing process severity. Thermal hydrolysis was performed at 170°C, hydrothermal carbonisation (HTC) was performed at 250°C, hydrothermal liquefaction (HTL) was performed at 350°C and supercritical water gasification (SCWG) was performed at 500°C. The level of nitrogen, phosphorus and potassium in the product streams was measured for each feedstock. Nitrogen is present in the aqueous phase as organic-N and NH3-N. The proportion of organic-N is higher at lower temperatures. Extraction of phosphorus is linked to the presence of inorganics such as Ca, Mg and Fe in the feedstock. Microalgae and chicken manure release phosphorus more easily than other feedstocks. Copyright © 2015. Published by Elsevier Ltd.

In-Line Heat Treatment and Hot Rolling

NASA Astrophysics Data System (ADS)

Raudensky, M.; Horsky, J.; Hnizdil, M. P.; Pohanka, Kotrbacek M.

2011-01-01

In-line heat treatment of rolled materials is becoming increasingly used at hot rolling plants. The advantage of this method is the achievement of required material structure without the necessity of reheating. This paper describes a design procedure for cooling sections for the purpose of obtaining the required structure and mechanical properties. The procedure is typically used for the cooling of tubes, rails, long products and plates. Microstructure and nature of grains, grain size and composition determine the overall mechanical behaviour of steel. Heat treatment provides an efficient way to manipulate the properties of steel by controlling the cooling rate. The rate of cooling is defined by a heat transfer coefficient (HTC). Good controllability of HTC can be reached using either air-water or water nozzles. Thus, an on-line heat treatment with the assistance of spray nozzles enables a manufacturing process that can improve product performance by increasing steel strength, hardness and other desirable characteristics. These techniques also allow selective hardening, such that selective areas of a single object can be subjected to different treatments. An experimental stand designed for the study of cooling steel samples has been built at the Brno University of Technology. The stand comprises a movable trolley containing a test sample which moves under the spray at a given velocity. Sensors indicate the temperature history of the tested material. This experimental stand enables simulation of a variety of cooling regimes and evaluates the final structure of tested samples. The same experimental stand is also a tool for use in the design of cooling sections in order to find the required heat treatment procedure and final structure. Examples of the cooling of rails and tubes are given in the paper.

Fabrication of efficient graphene-doped polymer/fullerene bilayer organic solar cells in air using spin coating followed by ultrasonic vibration post treatment

NASA Astrophysics Data System (ADS)

Zabihi, Fatemeh; Chen, Qianli; Xie, Yu; Eslamian, Morteza

2016-12-01

In this work, in an attempt to improve the performance and lifetime of organic solar cells, P3HT photon absorbing polymer was doped with graphene (G) nano-sheets, to make light harvesting G-P3HT composite thin film. The composite this film was then employed as the donor of a bilayer organic solar cell with the structure of glass/ITO/PEDOT:PSS/G-P3HT/C60/Al. The reference P3HT:PCBM bulk heterojunction solar cell was also fabricated for comparison. All solution-processed layers were made by spin coating in humid air (Shanghai, China); C60 and Al were deposited by thermal evaporation. An effective mechanical treatment approach developed by the authors, i.e. the application of forced ultrasonic vibration on the wet spun-on films, was used to improve the dispersion of graphene in G-P3HT composite films to obtain a uniform nanostructure. This mechanical method eliminates tedious and expensive chemical steps, currently performed to engineer the structure of organic solar cells. It is evidenced that the G-P3HT composite thin films, post treated by ultrasonic vibration at the optimum vibration duration, possess superior electrical conductivity, charge carrier mobility and density, uniform surface potential distribution, and lower surface roughness, compared to those of P3HT and G-P3HT thin films made without vibration. The results show significant improvement in the power conversion efficiency (PCE) of vibration-treated G-P3HT/C60 cell (PCE = 5.17%, the highest reported for this structure), substantiating the strong positive effect of using graphene and forced vibration for the fabrication of P3HT active layer in the bilayer cell structure.

The Selimiye Mosque of Edirne, Turkey - AN Immersive and Interactive Virtual Reality Experience Using Htc Vive

NASA Astrophysics Data System (ADS)

Kersten, T. P.; Büyüksalih, G.; Tschirschwitz, F.; Kan, T.; Deggim, S.; Kaya, Y.; Baskaraca, A. P.

2017-05-01

Recent advances in contemporary Virtual Reality (VR) technologies are going to have a significant impact on veryday life. Through VR it is possible to virtually explore a computer-generated environment as a different reality, and to immerse oneself into the past or in a virtual museum without leaving the current real-life situation. For such the ultimate VR experience, the user should only see the virtual world. Currently, the user must wear a VR headset which fits around the head and over the eyes to visually separate themselves from the physical world. Via the headset images are fed to the eyes through two small lenses. Cultural heritage monuments are ideally suited both for thorough multi-dimensional geometric documentation and for realistic interactive visualisation in immersive VR applications. Additionally, the game industry offers tools for interactive visualisation of objects to motivate users to virtually visit objects and places. In this paper the generation of a virtual 3D model of the Selimiye mosque in the city of Edirne, Turkey and its processing for data integration into the game engine Unity is presented. The project has been carried out as a co-operation between BİMTAŞ, a company of the Greater Municipality of Istanbul, Turkey and the Photogrammetry & Laser Scanning Lab of the HafenCity University Hamburg, Germany to demonstrate an immersive and interactive visualisation using the new VR system HTC Vive. The workflow from data acquisition to VR visualisation, including the necessary programming for navigation, is described. Furthermore, the possible use (including simultaneous multiple users environments) of such a VR visualisation for a CH monument is discussed in this contribution.

75 FR 54854 - Wooden Bedroom Furniture From the People's Republic of China: Partial Rescission of Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-09

... Hospitality Product Mfg., Co., Ltd. Shanghai Kent Furniture Co., Ltd. Shanghai Season Industry & Commerce Co... International, Ltd., Super Art Furniture Co., Ltd., Artwork Metal and Plastic Co., Ltd., Jibson Industries, Ltd... Hospitality, Inc. Changshu HTC Import & Export Co., Ltd. Chuan Fa Furniture Factory Contact Co., Ltd. Decca...

76 FR 58537 - In the Matter of Certain Personal Data and Mobile Communications Devices and Related Software...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-21

... subsystems. (HTC Pet. 30-35). (4) Whether the final ID's applications of the claim constructions for... below: (1) Whether the final ID's applications of the claim constructions for ``linking actions to the... has determined to review certain claim constructions, as well as the final ID's determinations...

3H-tetracycline as a proxy for 41Ca for measuring dietary perturbations of bone resorption

NASA Astrophysics Data System (ADS)

Weaver, Connie; Cheong, Jennifer; Jackson, George; Elmore, David; McCabe, George; Martin, Berdine

2007-06-01

Our group is interested in evaluating early effects of dietary interventions on bone loss. Postmenopausal women lose bone following reduction in estrogen which leads to increased risk of fracture. Traditional means of monitoring bone loss and effectiveness of treatments include changes in bone density, which takes 6 months to years to observe effects, and changes in biochemical markers of bone turnover, which are highly variable and lack specificity. Prelabeling bone with 41Ca and measuring urinary 41Ca excretion with accelerator mass spectrometry provides a sensitive, specific, and rapid approach to evaluating effectiveness of treatment. To better understand 41Ca technology as a tool for measuring effective treatments on reducing bone resorption, we perturbed bone resorption by manipulating dietary calcium in rats. We used 3H-tetracycline (3H-TC) as a proxy for 41Ca and found that a single dose is feasible to study bone resorption. Suppression of bone resorption, as measured by urinary 3H-TC, by dietary calcium was observed in rats stabilized after ovariectomy, but not in recently ovariectomized rats.

Hydration properties and texture fingerprints of easy- and hard-to-cook bean varieties

PubMed Central

Kinyanjui, Peter K; Njoroge, Daniel M; Makokha, Anselimo O; Christiaens, Stefanie; Ndaka, Daniel S; Hendrickx, Marc

2015-01-01

The objective of this study was to understand the factors that affect the hydration and cooking profiles of different bean varieties. During this study, nine bean varieties were classified as either easy-to-cook (ETC) or hard-to-cook (HTC) based on a subjective finger pressing test and an objective cutting test. Rose coco, Red haricot, and Zebra beans were classified as ETC, while Canadian wonder, Soya fupi, Pinto, non-nodulating, Mwezi moja, Gwaku, and New mwezi moja were HTC. The effect of different soaking (pre)-treatments on the cooking behavior and/or water absorption of whole or dehulled beans was investigated. Dehulling, soaking in high pH and monovalent salt solutions reduced the cooking time of beans, while soaking in low pH and CaCl2 solutions increased the cooking time. Moisture uptake was faster in ETC and dehulled beans. Soaking at high temperatures also increased the hydration rate. The results point to pectin-related aspects and the rate of water uptake as possible factors that influence the cooking rate of beans. PMID:25650021

Intensive Group Learning and On-Site Services to Improve Sexual and Reproductive Health Among Young Adults in Liberia: A Randomized Evaluation of HealthyActions.

PubMed

Firestone, Rebecca; Moorsmith, Reid; James, Simon; Urey, Marilyn; Greifinger, Rena; Lloyd, Danielle; Hartenberger-Toby, Lisa; Gausman, Jewel; Sanoe, Musa

2016-09-28

Young Liberians, particularly undereducated young adults, face substantial sexual and reproductive health (SRH) challenges, with low uptake of contraceptive methods, high rates of unintended pregnancy, and low levels of knowledge about HIV status. The purpose of this study was to assess the impact of a 6-day intensive group learning intervention combined with on-site SRH services (called HealthyActions) among out-of-school young adults, implemented through an existing alternative education program, on uptake of contraception and HIV testing and counseling (HTC). The intervention was implemented among young women and men ages 15-35 who were enrolled in alternative basic education learning sites in 5 counties of Liberia. We conducted a randomized evaluation to assess program impact. Baseline data were collected in January-March 2014, and endline data in June-July 2014. Key outcomes of condom use, contraceptive use, and HTC were estimated with difference-in-difference models using fixed effects. All analyses were conducted in Stata 13. We assessed outcomes for 1,157 learners at baseline and 1,052 learners at endline, across 29 treatment and 26 control sites. After adjusting for potential confounders, learners in the HealthyActions intervention group were 12% less likely to report never using a condom with a regular partner over the last month compared with the control group (P = .02). Female learners who received HealthyActions were 13% more likely to use any form of modern contraception compared with learners in control sites (P<.001), with the greatest increase in the use of contraceptive implants. Learners in HealthyActions sites were 45% more likely to have received HTC (P<.001). Providing intensive group learning in a supportive environment coupled with on-site health services improved SRH outcomes among participating learners. The focus of HealthyActions on participatory learning for low-literacy populations presents an adaptable solution for health programming across Liberia and the region. © Firestone et al.

Improved accuracy in high-temperature conversion elemental analyzer δ18O measurements of nitrogen-rich organics.

PubMed

Hunsinger, Glendon B; Stern, Libby A

2012-03-15

The use of high-temperature conversion (HTC) reduction systems interfaced with isotope ratio mass spectrometers for δ(18)O measurements of nitrogen-containing organic materials is complicated by isobaric interference from (14)N(16)O(+). This ion is produced in the ion source when N(2) reacts with trace oxygen shifting the m/z 30 baseline prior to elution of CO. We compared adaptations to a typical HTC system (TC/EA) to determine the best method to measure the δ(18)O values of nitrogen-rich organic substrates including: (1) 0.6 and 1.5 m 5 Å molecular sieve GC columns; (2) reduction of N(2) peak via He dilution; and (3) diversion of N(2) to waste via an automated four-port valve. These methods were applied to caffeine (IAEA-600), glycine, 4-nitroacetanilide, pentaerythritol tetranitrate (PETN) and cyclotrimethylene trinitramine (RDX), as well as pure and sodium azide-doped benzoic acid (IAEA-601) and sucrose (IAEA-CH6). The efficiency of N(2) production in the HTC interface was highly variable among these compounds. Both the longer column and the dilutor improved, but did not eliminate, the adverse effects of nitrogen. The diversion of N(2) adequately addressed the nitrogen-induced problems as indicated by: (1) consistent m/z 30 background offset between reference and sample CO for both N-free and N-rich materials; (2) production of the highest δ(18)O values; and (3) high correlation between the increase in the δ(18)O values relative to the GC-only measurements and the N(2) peak area. Additional validation would require N-rich oxygen isotope standards for inter-laboratory comparisons. Further, more stringent methodology may improve the poor inter-laboratory δ(18)O reproducibility of IAEA-600. Published in 2012 by John Wiley & Sons, Ltd.

Chemistry of solutions from the 13°N East Pacific Rise hydrothermal site

NASA Astrophysics Data System (ADS)

Michard, G.; Albarède, F.; Michard, A.; Minster, J.-F.; Charlou, J.-L.; Tan, N.

1984-03-01

Ten samples were recovered by the submersible "Cyana" submersible from two groups of hydrothermal vents located 2600 m deep along the East Pacific Rise at 13°N. The maximum measured temperature was 317°C and minimum pH 3.8. A systematic determination of major and trace elements has been carried out and mixing lines between a high-temperature component (HTC) and seawater are observed. The water chemistry of the HTC slightly differs for several elements at the two sites. This HTC is deprived of SO 4 and Mg and is greatly enriched in most other species. Maximum concentrations are (in units per kg): Cl = 0.72mol; Br = 1.1mmol; Na = 0.55mol; K = 29mmol; Rb = 14 μmol; Ca = 52mmol; Sr = 170 μmol; Mn = 750 μmol; Fe = 1mmol; Al = 15 μmol; Si = 21mmol. For many elements, the magnitude of the anomaly relative to seawater does not compare with the results obtained from the Galapagos or East Pacific Rise 21°N. The enrichment of cations relative to seawater is likely related to the huge Cl excess through charge balance. The Br/Cl ratio is close to that for seawater. However, it is not clear whether the Cl excess is due to gas release or basalt hydration (formation of amphibole chlorite or epidote). P-T dependence of SiO 2 solubility suggests that water-rock interaction last occurred at a depth in excess of 1 km below the sea floor. A mixing line of 87Sr/ 86Sr vs. Mg/Sr demonstrates that the HTCs have a nearly identical 87Sr/ 86Sr ratio of 0.7041 for both sites. A water/rock ratio of about 5 is inferred, which differs from the 1.5 value obtained at 21°N.

Retention in care and reasons for discontinuation of lifelong antiretroviral therapy in a cohort of Cameroonian pregnant and breastfeeding HIV-positive women initiating 'Option B+' in the South West Region.

PubMed

Atanga, Pascal N; Ndetan, Harrison T; Achidi, Eric A; Meriki, Henry D; Hoelscher, Michael; Kroidl, Arne

2017-02-01

To assess linkage and retention in care along the PMTCT cascade in HIV-positive pregnant and breastfeeding women initiating Option B+ in Cameroon. We prospectively determined uptake of HIV testing and counselling (HTC), uptake of ART and retention in care after Option B+ initiation between October 2013 and December 2014 in pregnant and breastfeeding women from five sites within the Kumba Health District. Retention in care was assessed over at least 12 months follow-up and estimated by Kaplan-Meier analysis. During follow-up, tracing outcomes and reasons for discontinuing treatment were documented. The uptake of HTC of 5813 women with unknown HIV status was 98.5%, 251 (4.4%) were newly diagnosed HIV positive, and ART uptake in women eligible to start Option B+ was 96.8%. We enrolled 268 women initiating lifelong ART in the follow-up. Overall, 65 (24.3%) discontinued treatment, either defined by loss to follow-up (44.6%) or actively stopped treatment (55.8%). Retention in care was 88.0% and 81.1% at 6 and 12 months, respectively. Discontinuation was significantly associated in multivariate analysis with small sites and high staff turnover [aOR 2.5 (95% CI 1.6, 3.9), P < 0.001]. Main reasons for stopping treatment were HIV status denial and stigma (52.8%), religious reasons (25.0%) and lack of transport fare (11.1%). We observed good uptake of HTC, ART and retention in care, which declined over time. Discontinuation of Option B+ was highest at small sites with a high staff turnover. Improved staffing, adequate task shifting and community interventions to track defaulters including reducing stigma and religious beliefs may improve Option B+ retention. © 2016 John Wiley & Sons Ltd.

Pharmaceuticals in water, fish and osprey nestlings in Delaware River and Bay

USGS Publications Warehouse

Bean, Thomas G.; Rattner, Barnett A.; Lazarus, Rebecca S.; Day, Daniel D.; Burket, S. Rebekah; Brooks, Bryan W.; Haddad, Samuel P.; Bowerman, William W.

2018-01-01

Exposure of wildlife to Active Pharmaceutical Ingredients (APIs) is likely to occur but studies of risk are limited. One exposure pathway that has received attention is trophic transfer of APIs in a water-fish-osprey food chain. Samples of water, fish plasma and osprey plasma were collected from Delaware River and Bay, and analyzed for 21 APIs. Only 2 of 21 analytes exceeded method detection limits in osprey plasma (acetaminophen and diclofenac) with plasma levels typically 2–3 orders of magnitude below human therapeutic concentrations (HTC). We built upon a screening level model used to predict osprey exposure to APIs in Chesapeake Bay and evaluated whether exposure levels could have been predicted in Delaware Bay had we just measured concentrations in water or fish. Use of surface water and BCFs did not predict API concentrations in fish well, likely due to fish movement patterns, and partitioning and bioaccumulation uncertainties associated with these ionizable chemicals. Input of highest measured API concentration in fish plasma combined with pharmacokinetic data accurately predicted that diclofenac and acetaminophen would be the APIs most likely detected in osprey plasma. For the majority of APIs modeled, levels were not predicted to exceed 1 ng/mL or method detection limits in osprey plasma. Based on the target analytes examined, there is little evidence that APIs represent a significant risk to ospreys nesting in Delaware Bay. If an API is present in fish orders of magnitude below HTC, sampling of fish-eating birds is unlikely to be necessary. However, several human pharmaceuticals accumulated in fish plasma within a recommended safety factor for HTC. It is now important to expand the scope of diet-based API exposure modeling to include alternative exposure pathways (e.g., uptake from landfills, dumps and wastewater treatment plants) and geographic locations (developing countries) where API contamination of the environment may represent greater risk.

Achieving phase transformation and structure control of crystalline anatase TiO2@C hybrids from titanium glycolate precursor and glucose molecules.

PubMed

Cheng, Gang; Stadler, Florian J

2015-01-15

Considerable efforts have focused on functional TiO2@carbonaceous hybrid nanostructured materials (TiO2@C) to satisfy the future requirements of environmental photocatalysis and energy storage using these advanced materials. In this study, we developed a two-step solution-phase reaction to prepare hybrid TiO2@C with tuneable structure and composition from the hydrothermal carbonization (HTC) of glucose. X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA) were used to determine the crystallite size, composition, and phase purity. The results of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high resolution TEM (HRTEM) showed that the morphology of the as-synthesized TiO2@C hybrids could be controlled by varying the amount of glucose, also acting as the carbon source. Based on the observations made with different glucose concentrations, a formation mechanism of nanoparticulate and nanoporous TiO2@C hybrids was proposed. In addition, the as-synthesized TiO2@C hybrids with different compositions and structures showed enhanced adsorption of visible light and improved dye-adsorption capacity, which supported their potential use as photocatalysts with good activity. This new synthetic approach, using a nanoprecursor, provides a simple and versatile way to prepare TiO2@C hybrids with tuneable composition, structures, and properties, and is expected to lead to a family of composites with designed properties. Copyright © 2014 Elsevier Inc. All rights reserved.

76 FR 56760 - Granting of Request for Early Termination of the Waiting Period Under the Premerger Notification...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-14

... Partners II, L.P.; OCM Principal Opportunities Fund III, L.P. 20111257 G Algonquin Power & Utilities Corp.; Atmos Energy Corporation; Algonquin Power & Utilities Corp. 08/26/2011 20111178 G Smith Family Voting...; Beats Electronics, LLC; HTC Corporation. 20111270 G Atlantic Power Corporation; Capital Power Income L.P...

Measurement of heat transfer coefficient using termoanemometry methods

NASA Astrophysics Data System (ADS)

Dančová, P.; Sitek, P.; Vít, T.

2014-03-01

This work deals with a measurement of heat transfer from a heated flat plate on which a synthetic jet impacts perpendicularly. Measurement of a heat transfer coefficient (HTC) is carried out using the hot wire anemometry method with glue film probe Dantec 55M47. The paper brings also results of velocity profiles measurements and turbulence intensity calculations.

Independent and collective roles of surface structures at different length scales on pool boiling heat transfer

PubMed Central

Li, Calvin H.; Rioux, Russell P.

2016-01-01

Spherical Cu nanocavity surfaces are synthesized to examine the individual role of contact angles in connecting lateral Rayleigh-Taylor wavelength to vertical Kevin-Helmholtz wavelength on hydrodynamic instability for the onset of pool boiling Critical Heat Flux (CHF). Solid and porous Cu pillar surfaces are sintered to investigate the individual role of pillar structure pitch at millimeter scale, named as module wavelength, on hydrodynamic instability at CHF. Last, spherical Cu nanocavities are coated on the porous Cu pillars to create a multiscale Cu structure, which is studied to examine the collective role and relative significance of contact angles and module wavelength on hydrodynamic instability at CHF, and the results indicate that module wavelength plays the dominant role on hydrodynamic instability at CHF when the height of surface structures is equal or above ¼ Kelvin-Helmholtz wavelength. Pool boiling Heat Transfer Coefficient (HTC) enhancements on spherical Cu nanocavity surfaces, solid and porous Cu pillar surfaces, and the integrated multiscale structure have been investigated, too. The experimental results reveal that the nanostructures and porous pillar structures can be combined together to achieve even higher enhancement of HTC than that of individual structures. PMID:27841322

The Impact of Married Individuals Learning HIV Status in Malawi: Divorce, Number of Sexual Partners, and Condom Use With Spouses

PubMed Central

Kohler, Hans-Peter; Behrman, Jere R.

2015-01-01

This article assesses how married individuals’ knowledge of HIV status gained through HIV testing and counseling (HTC) affects divorce, the number of sexual partners, and the use of condoms within marriage. This study improves upon previous studies on this topic because the randomized incentives affecting the propensity to be tested for HIV permit control for selective testing. Instrumental variable probit and linear models are estimated, using a randomized experiment administered as part of the Malawi Longitudinal Study of Families and Health (MLSFH). The results indicate that knowledge of HIV status (1) does not affect chances of divorce for either HIV-negative or HIV-positive respondents; (2) reduces the number of reported sexual partners among HIV-positive respondents; and (3) increases reported condom use with spouses for both HIV-negative and HIV-positive respondents. These results imply that individuals actively respond to information about their HIV status that they learn during HTC, invoking protective behavior against future risk of HIV/AIDS for them-selves and their actual and potential sexual partners. Some limitations of this study are a small sample size for those who are HIV-positive and dependence on self-reported sexual behaviors. PMID:25582891

The Impact of Married Individuals Learning HIV Status in Malawi: Divorce, Number of Sexual Partners, and Condom Use With Spouses.

PubMed

Fedor, Theresa M; Kohler, Hans-Peter; Behrman, Jere R

2015-02-01

This article assesses how married individuals' knowledge of HIV status gained through HIV testing and counseling (HTC) affects divorce, the number of sexual partners, and the use of condoms within marriage. This study improves upon previous studies on this topic because the randomized incentives affecting the propensity to be tested for HIV permit control for selective testing. Instrumental variable probit and linear models are estimated, using a randomized experiment administered as part of the Malawi Longitudinal Study of Families and Health (MLSFH). The results indicate that knowledge of HIV status (1) does not affect chances of divorce for either HIV-negative or HIV-positive respondents; (2) reduces the number of reported sexual partners among HIV-positive respondents; and (3) increases reported condom use with spouses for both HIV-negative and HIV-positive respondents. These results imply that individuals actively respond to information about their HIV status that they learn during HTC, invoking protective behavior against future risk of HIV/AIDS for themselves and their actual and potential sexual partners. Some limitations of this study are a small sample size for those who are HIV-positive and dependence on self-reported sexual behaviors.

Experimental research and numerical simulation on cryogenic line chill-down process

NASA Astrophysics Data System (ADS)

Jin, Lingxue; Cho, Hyokjin; Lee, Cheonkyu; Jeong, Sangkwon

2018-01-01

The empirical heat transfer correlations are suggested for the fast cool down process of the cryogenic transfer line from room temperature to cryogenic temperature. The correlations include the heat transfer coefficient (HTC) correlations for single-phase gas convection and film boiling regimes, minimum heat flux (MHF) temperature, critical heat flux (CHF) temperature and CHF. The correlations are obtained from the experimental measurements. The experiments are conducted on a 12.7 mm outer diameter (OD), 1.25 mm wall thickness and 7 m long stainless steel horizontal pipe with liquid nitrogen (LN2). The effect of the lengthwise position is verified by measuring the temperature profiles in near the inlet and the outlet of the transfer line. The newly suggested heat transfer correlations are applied to the one-dimensional homogeneous transient model to simulate the cryogenic line chill-down process, and the chill-down time and the cryogen consumption are well predicted in the mass flux range from 26.0 kg/m2 s to 73.6 kg/m2 s through the correlations.

Holodeck-ISS Experience

NASA Technical Reports Server (NTRS)

Rainbolt, Phillip

2016-01-01

For the duration of my internship here at JSC for the summer 2016 session, the main project that I worked on dealt with hybrid reality simulations of the ISS. As an ER6 intern for the spacecraft software division, the main project that I worked alongside others was with regards to the Holodeck Virtual Reality Project, specifically with the ISS experience, with the use of the HTC Vive and controllers.

Cyberinfrastructure and Scientific Collaboration: Application of a Virtual Team Performance Framework with Potential Relevance to Education. WCER Working Paper No. 2010-12

ERIC Educational Resources Information Center

Kraemer, Sara; Thorn, Christopher A.

2010-01-01

The purpose of this exploratory study was to identify and describe some of the dimensions of scientific collaborations using high throughput computing (HTC) through the lens of a virtual team performance framework. A secondary purpose was to assess the viability of using a virtual team performance framework to study scientific collaborations using…

Intensive Group Learning and On-Site Services to Improve Sexual and Reproductive Health Among Young Adults in Liberia: A Randomized Evaluation of HealthyActions

PubMed Central

Firestone, Rebecca; Moorsmith, Reid; James, Simon; Urey, Marilyn; Greifinger, Rena; Lloyd, Danielle; Hartenberger-Toby, Lisa; Gausman, Jewel; Sanoe, Musa

2016-01-01

ABSTRACT Introduction: Young Liberians, particularly undereducated young adults, face substantial sexual and reproductive health (SRH) challenges, with low uptake of contraceptive methods, high rates of unintended pregnancy, and low levels of knowledge about HIV status. The purpose of this study was to assess the impact of a 6-day intensive group learning intervention combined with on-site SRH services (called HealthyActions) among out-of-school young adults, implemented through an existing alternative education program, on uptake of contraception and HIV testing and counseling (HTC). Methods: The intervention was implemented among young women and men ages 15–35 who were enrolled in alternative basic education learning sites in 5 counties of Liberia. We conducted a randomized evaluation to assess program impact. Baseline data were collected in January–March 2014, and endline data in June–July 2014. Key outcomes of condom use, contraceptive use, and HTC were estimated with difference-in-difference models using fixed effects. All analyses were conducted in Stata 13. Results: We assessed outcomes for 1,157 learners at baseline and 1,052 learners at endline, across 29 treatment and 26 control sites. After adjusting for potential confounders, learners in the HealthyActions intervention group were 12% less likely to report never using a condom with a regular partner over the last month compared with the control group (P = .02). Female learners who received HealthyActions were 13% more likely to use any form of modern contraception compared with learners in control sites (P<.001), with the greatest increase in the use of contraceptive implants. Learners in HealthyActions sites were 45% more likely to have received HTC (P<.001). Conclusion: Providing intensive group learning in a supportive environment coupled with on-site health services improved SRH outcomes among participating learners. The focus of HealthyActions on participatory learning for low-literacy populations presents an adaptable solution for health programming across Liberia and the region. PMID:27688717

How home HIV testing and counselling with follow-up support achieves high testing coverage and linkage to treatment and prevention: a qualitative analysis from Uganda.

PubMed

Ware, Norma C; Wyatt, Monique A; Asiimwe, Stephen; Turyamureeba, Bosco; Tumwesigye, Elioda; van Rooyen, Heidi; Barnabas, Ruanne V; Celum, Connie L

2016-01-01

The successes of HIV treatment scale-up and the availability of new prevention tools have raised hopes that the epidemic can finally be controlled and ended. Reduction in HIV incidence and control of the epidemic requires high testing rates at population levels, followed by linkage to treatment or prevention. As effective linkage strategies are identified, it becomes important to understand how these strategies work. We use qualitative data from The Linkages Study, a recent community intervention trial of community-based testing with linkage interventions in sub-Saharan Africa, to show how lay counsellor home HIV testing and counselling (home HTC) with follow-up support leads to linkage to clinic-based HIV treatment and medical male circumcision services. We conducted 99 semi-structured individual interviews with study participants and three focus groups with 16 lay counsellors in Kabwohe, Sheema District, Uganda. The participant sample included both HIV+ men and women (N=47) and HIV-uncircumcised men (N=52). Interview and focus group audio-recordings were translated and transcribed. Each transcript was summarized. The summaries were analyzed inductively to identify emergent themes. Thematic concepts were grouped to develop general constructs and framing propositional statements. Trial participants expressed interest in linking to clinic-based services at testing, but faced obstacles that eroded their initial enthusiasm. Follow-up support by lay counsellors intervened to restore interest and inspire action. Together, home HTC and follow-up support improved morale, created a desire to reciprocate, and provided reassurance that services were trustworthy. In different ways, these functions built links to the health service system. They worked to strengthen individuals' general sense of capability, while making the idea of accessing services more manageable and familiar, thus reducing linkage barriers. Home HTC with follow-up support leads to linkage by building "social bridges," interpersonal connections established and developed through repeated face-to-face contact between counsellors and prospective users of HIV treatment and male circumcision services. Social bridges link communities to the service system, inspiring individuals to overcome obstacles and access care.

Long-term organic selenium supplementation overcomes the trade-off between immune and antioxidant systems in pacu (Piaractus mesopotamicus).

PubMed

Takahashi, Leonardo Susumu; Biller-Takahashi, Jaqueline Dalbello; Mansano, Cleber Fernando Menegasso; Urbinati, Elisabeth Criscuolo; Gimbo, Rodrigo Yukihiro; Saita, Marcos Vinícius

2017-01-01

Selenium (Se) is an essential nutrient for antioxidant defenses in fish because of its role in preventing immunosuppression caused by oxidative stress. In this study it was demonstrated the relation between the oxidative stress and immune status after a long Se supplementation period, as a result of the evaluation of immunological, hematological and antioxidant responses, as well as growth performance of pacu fed diets supplemented with different concentrations of organic selenium (0, 0.3, 0.6, 0.9, and 1.8 mg Se-yeast/kg, but the final analyzed selenium concentrations were 0.72, 0.94, 1.15, 1.57 and 2.51 mg/kg, respectively) for 65 days. Dietary Se supplementation at 1.15 mg Se-yeast/kg (analyzed value) restored the production of antioxidant enzymes (glutathione peroxidase (GPx) and glutathione S-transferase (GST)), and consequently allowed the increased of some immunological parameters (leukocyte respiratory burst activity and lysozyme activity), hematological parameters (red blood cell count (RBC), hematocrit (HTC), mean corpuscular volume (MCV), and white blood cell count (WBC)). Se supplementation in pacu diets at 1.15 mg Se-yeast/kg for 65 days improved immune response and antioxidant defenses, suggesting that oxidative stress impairs immune system response to prevent excessive reactive oxygen species in cells and indicating the occurrence of a physiological trade-off between immune and antioxidant systems. Higher Se levels, such as 1.57 mg Se-yeast/kg increased the leukocyte respiratory burst activity, the WBC and thrombocyte counts, the RBC and HTC, and the GST and GPx enzymes. However, 2.51 mg Se-yeast/kg decreased the lysozyme levels, the WBC and thrombocyte counts, the RBC, HTC and MCV, and the GST and GPx enzymes. Those findings are important to future studies because showed the negative effect of oxidative stress on immunity, and may help to prevent any inhibition of the expected immune response after immunomodulators administration and vaccination. Also it was possible to meet the dietary selenium requirement of pacu, that was estimated to be 1.56 mg/kg. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of nerve blockade on forearm and finger skin blood flow during body heating and cooling.

PubMed

Saumet, J L; Degoute, C S; Saumet, M; Abraham, P

1992-08-01

To determine the role of the active cutaneous vasodilatator response in forearm and finger skin, direct assessment of only skin blood flow was performed before and after musculocutaneous and median nerve blockade during whole body heating and cooling. Forearm laser Doppler flow (LDF forearm), forearm heat thermal clearance (HTC forearm), and finger laser Doppler flow (LDF finger) were monitored in the nerve blocked skin and contralateral untreated skin (control). In the pre-blockade period, no significant differences were found between experimental and control arm skin. After nerve block a significant increase occurred only in LDF finger, which rose from 4.3 +/- 0.6 to 6.0 +/- 0.5 volts (p less than 0.05). During whole body heating LDF forearm and HTC forearm increased significantly on both arms. The increase in LDF forearm was greater (p less than 0.05) in control (18.3 +/- 1.2 volts) than in nerve blocked skin (14.6 +/- 1.8 volts) and occurred earlier. The same tendency was observed in HTC forearm between nerve blocked skin (0.522 +/- 0.06 W.m-1.degrees C-1) and control 0.671 +/- 0.037 W.m-1.degrees C-1) (NS). LDF raise up to 6.6 +/- 0.5 and 6.8 +/- 0.5 volts in the blocked finger and in the control respectively. During cooling LDF finger in the control decreased to 1.3 +/- 0.1 volt and was significantly (p less than 0.05) lower than in the resting period, and lower than that in the nerve blocked finger (3.4 +/- 0.8 volts) (p less than 0.05). We conclude that the active vasodilatator system plays an important role as far as the timing and the amplitude of the cutaneous vasodilatator response to whole body heating in the forearm but not in the finger. At thermal neutrality, the vascular vasoconstrictor tone is high to the finger but not to the forearm. The vasoconstrictor response to cooling occurred only in the finger.

The glucocorticoid receptor regulates the binding of C/EPBbeta on the alpha-1-acid glycoprotein promoter in vivo.

PubMed

Savoldi, G; Fenaroli, A; Ferrari, F; Rigaud, G; Albertini, A; Di Lorenzo, D

1997-12-01

A complex interaction between the Glucocorticoid Receptor (GR), C/EBPbeta, and other transcription factors activate the Alpha-1 Acid Glycoprotein (AGP) promoter in HTC(JZ-1) rat hepatoma culture cells. This effect is mediated by the so-called Steroid Responsive Unit (SRU) of the AGP promoter that contains several binding sites for C/EBP transcription factors, some of which overlap with the Glucocorticoid Responsive Element (GRE). Our in vivo footprinting experiments revealed that the GRE- and the C/EBP-binding sites were already occupied glucocorticoid dependently in HTC(JZ-1) cells 10 min after dexamethasone administration (10(-6) M). Furthermore, local changes in the chromatine structure shown by the appearance of DNAse I hypersensitive sites (HS sites) also took place. These changes were probably dependent on a tissue-specific organization of the chromatine at the SRU because they were not detectable in a different glucocorticoid-responsive cell line (PC12) that did not express AGP. Here, we have also shown that withdrawal of dexamethasone or addition of the anti-glucocorticoid RU486 were able to revert the pattern induced by dexamethasone in vivo. The disappearance of the protected region and the hypersensitive sites, typical of the hormone activated promoter, confirmed the necessity of the GR to be bound by the agonist and the inability of the GR-antagonist complex to bind the DNA. By functional assays, we showed that the occupancy of the SRU by these transcriptional proteins in vivo correlated with the activation of the AGP gene transcription. With these results, we have shown that one of the functions of the GR to activate transcription of the AGP gene is to recruit C/EBPbeta and to maintain it bound at its target DNA sequences (SRU). This process was not accomplished by RU486.

Environmental Assessment Newport Research Facility Irish Hill

DTIC Science & Technology

2011-09-12

Classification Symbol Burdett silt loam, 3 to 8 percent BuB Not Hydric Prime Farmland if Drained slopes Honeoye and Lansing silt loams, Hre Not...Part USDA - llap unit symbol BuB ~ CsB HrE HsD HIB HtC LnC LnD McB MIS ~ MoB I MoD NaB NaC NaD I 1R0 •ShF llap unit Mille Rating

Relative risk reduction is useful metric to standardize effect size for public heath interventions for translational research.

PubMed

Mirzazadeh, Ali; Malekinejad, Mohsen; Kahn, James G

2015-03-01

Heterogeneity of effect measures in intervention studies undermines the use of evidence to inform policy. Our objective was to develop a comprehensive algorithm to convert all types of effect measures to one standard metric, relative risk reduction (RRR). This work was conducted to facilitate synthesis of published intervention effects for our epidemic modeling of the health impact of human immunodeficiency virus [HIV testing and counseling (HTC)]. We designed and implemented an algorithm to transform varied effect measures to RRR, representing the proportionate reduction in undesirable outcomes. Our extraction of 55 HTC studies identified 473 effect measures representing unique combinations of intervention-outcome-population characteristics, using five outcome metrics: pre-post proportion (70.6%), odds ratio (14.0%), mean difference (10.2%), risk ratio (4.4%), and RRR (0.9%). Outcomes were expressed as both desirable (29.5%, eg, consistent condom use) and undesirable (70.5%, eg, inconsistent condom use). Using four examples, we demonstrate our algorithm for converting varied effect measures to RRR and provide the conceptual basis for advantages of RRR over other metrics. Our review of the literature suggests that RRR, an easily understood and useful metric to convey risk reduction associated with an intervention, is underused by original and review studies. Copyright © 2015 Elsevier Inc. All rights reserved.

Nesting of colon and ovarian cancer cells in the endothelial niche is associated with alterations in glycan and lipid metabolism.

PubMed

Halama, Anna; Guerrouahen, Bella S; Pasquier, Jennifer; Satheesh, Noothan J; Suhre, Karsten; Rafii, Arash

2017-01-04

The metabolic phenotype of a cancer cell is determined by its genetic makeup and microenvironment, which dynamically modulates the tumor landscape. The endothelial cells provide both a promoting and protective microenvironment - a niche for cancer cells. Although metabolic alterations associated with cancer and its progression have been fairly defined, there is a significant gap in our understanding of cancer metabolism in context of its microenvironment. We deployed an in vitro co-culture system based on direct contact of cancer cells with endothelial cells (E4 + EC), mimicking the tumor microenvironment. Metabolism of colon (HTC15 and HTC116) and ovarian (OVCAR3 and SKOV3) cancer cell lines was profiled with non-targeted metabolic approaches at different time points in the first 48 hours after co-culture was established. We found significant, coherent and non-cell line specific changes in fatty acids, glycerophospholipids and carbohydrates over time, induced by endothelial cell contact. The metabolic patterns pinpoint alterations in hexosamine biosynthetic pathway, glycosylation and lipid metabolism as crucial for cancer - endothelial cells interaction. We demonstrated that "Warburg effect" is not modulated in the initial stage of nesting of cancer cell in the endothelial niche. Our study provides novel insight into cancer cell metabolism in the context of the endothelial microenvironment.

Identification of SNP in HSP90AB1 and its association with the relative thermotolerance and milk production traits in Indian dairy cattle.

PubMed

Sajjanar, Basavaraj; Deb, Rajib; Singh, Umesh; Kumar, Sushil; Brahmane, Manoj; Nirmale, Avinash; Bal, Santanu Kumar; Minhas, P S

2015-01-01

Heat shock proteins (Hsp) play crucial role in cellular thermotolerance and heat stress response. In the present work, Allele specific PCR (AS-PCR) was standardized to detect the nucleotide polymorphism within the HSP90AB1 gene (SNP g.4338T>C) in Indian breeds of dairy cattle. The identified genotypes were associated with relative thermotolerance in terms of physiological parameters and milk production traits. The results of the experiments revealed that the genotype frequency of CC, CT, and TT for Sahiwal were 0.05, 0.78, and 0.17, respectively, and in Frieswal, the frequencies were 0.20, 0.70, and 0.10, respectively. The average rectal temperature (ART) and average respiration rates (ARR) were recorded during peak summer stress and heat tolerance coefficient (HTC) was calculated. The association studies indicated that TT genotypes had significantly (P < 0.01) higher HTC and lower ARR values than CT and CC in both the breeds. The TT genotype animals also had better production parameter in terms of total milk yield (TMY) (P < 0.01). These findings may partly suggest the role of HSP90AB1 polymorphisms in the regulation of heat stress response and consequent effect on production traits. Nevertheless, involvement of other regulatory mechanisms cannot be overruled.

Results of kidney transplantation from high-terminal creatinine donors and the role of time-zero biopsy.

PubMed

Lin, N C; Yang, A H; King, K L; Wu, T H; Yang, W C; Loong, C C

2010-11-01

Deceased-donor kidney transplantation (DDKT) from high-terminal creatinine donors is associated with lower graft survival. These kidneys may be considered for discarding, worsening the organ shortage crisis. Using time-zero biopsy for histologic evaluation of these kidneys, we identified those organs eligible for transplantation, seeking to achieve better graft utility with comparable outcomes. From April 2004 to April 2008, 55 patients underwent DDKT. A time-zero biopsy was used to examine glomerulosclerosis, interstitial fibrosis, tubular atrophy, and arteriolar narrowing. A scoring system was used to determine a discard. Twenty-five patients received DDKT from donors whose terminal creatinine levels were >2.0 mg/dL (high terminal creatinine, HTC group) and 30 from donors whose terminal creatinine levels were <2.0 mg/dL (low terminal creatinine, LTC group). Patients who accepted kidneys from HTC donors had shorter waiting times (P = .011) but a higher incidence of delayed graft function after transplantation (P < .001). Nonetheless, 5-year graft survival rates were similar between the two groups. With a time-zero biopsy for histologic evaluation, kidneys recovered from high-terminal creatinine donors can be transplanted to overcome the organ shortage while achieving reasonable graft survival. Copyright © 2010 Elsevier Inc. All rights reserved.

Effect of Wind Flow on Convective Heat Losses from Scheffler Solar Concentrator Receivers

NASA Astrophysics Data System (ADS)

Nene, Anita Arvind; Ramachandran, S.; Suyambazhahan, S.

2018-05-01

Receiver is an important element of solar concentrator system. In a Scheffler concentrator, solar rays get concentrated at focus of parabolic dish. While radiation losses are more predictable and calculable since strongly related to receiver temperature, convective looses are difficult to estimate in view of additional factors such as wind flow direction, speed, receiver geometry, prior to current work. Experimental investigation was carried out on two geometries of receiver namely cylindrical and conical with 2.7 m2 Scheffler to find optimum condition of tilt to provide best efficiency. Experimental results showed that as compared to cylindrical receiver, conical receiver gave maximum efficiency at 45° tilt angle. However effect of additional factors like wind speed, wind direction on especially convective losses could not be separately seen. The current work was undertaken to investigate further the same two geometries using computation fluid dynamics using FLUENT to compute convective losses considering all variables such at tilt angle of receiver, wind velocity and wind direction. For cylindrical receiver, directional heat transfer coefficient (HTC) is remarkably high to tilt condition meaning this geometry is critical to tilt leading to higher convective heat losses. For conical receiver, directional average HTC is remarkably less to tilt condition leading to lower convective heat loss.

The study of ultrasonic irradiation effects on solid state powders of HTc superconductor YBa2Cu3O7-x

NASA Astrophysics Data System (ADS)

Kargar, Mahboubeh; Khoshnevisan, Bahram

2016-03-01

In this paper, an ultrasound assisted solid state synthesis method for high-temperature (HTc) YBa2Cu3O7-x (YBCO) superconductor nanostructures with different morphologies is presented. Here, the routine heat treatment of the powder mixture of as-prepared precursors is followed by the ultrasound irradiation inside various alcoholic solutions. Not only the influence of the ultrasound irradiation intensity and duration but also the influence of different solvents such as ethanol, methanol and 1-butanol with various vapor pressures and so various destruction powers were also studied on the morphology and particle size of the products. The various morphologies were studied by scanning electron microscope (SEM) which not only have been affected by intensity and type of alcoholic solvent but also sonication time and ultrasound power have significant role as well. Formation of the YBCO superconducting phase was examined by using Rietveld refinement of X-ray diffraction (XRD) which indicates the crystalline preferred growth in c-axis orientation in crystal. Magnetic susceptibility measurements showed the ultrasound waves had no important effect on the onset critical temperature of the prepared nanorods (about 91.64 K) which is compared with the bulk samples (Tc ˜ 92K).

The Transcorrelated Method Combined with the Variational Monte Carlo Calculation: Application to Atoms

NASA Astrophysics Data System (ADS)

Umezawa, Naoto; Tsuneyuki, Shinji; Ohno, Takahisa; Shiraishi, Kenji; Chikyow, Toyohiro

2005-03-01

The transcorrelated (TC) method is a useful approach to optimize the Jastrow-Slater-type many-body wave function FD. The basic idea of the TC method [1] is based on the similarity transformation of a many-body Hamiltonian H with respect to the Jastrow factor F: HTC=frac1F H F in order to incorporate the correlation effect into HTC. Both the F and D are optimized by minimizing the variance ^2=|Hrm TCD - E D |^2 d^3N x. The optimization for F is implemented by the variational Monte Carlo calculation, and D is determined by the TC self-consistent-field equation for the one-body wave functions φμ(x), which is derived from the functional derivative of ^2 with respect to φmu(x). In this talk, we will present the results given by the transcorrelated variational Monte Carlo (TC-VMC) method for the ground state [2] and the excited states of atoms [3]. [1]S. F. Boys and N. C. Handy, Proc. Roy. Soc. A, 309, 209; 310, 43; 310, 63; 311, 309 (1969). [2]N. Umezawa and S. Tsuneyuki, J. Chem. Phys. 119, 10015 (2003). [3]N. Umezawa and S. Tsuneyuki, J. Chem. Phys. 121, 7070 (2004).

Mobile health platform for pressure ulcer monitoring with electronic health record integration.

PubMed

Rodrigues, Joel J P C; Pedro, Luís M C C; Vardasca, Tomé; de la Torre-Díez, Isabel; Martins, Henrique M G

2013-12-01

Pressure ulcers frequently occur in patients with limited mobility, for example, people with advanced age and patients wearing casts or prostheses. Mobile information communication technologies can help implement ulcer care protocols and the monitoring of patients with high risk, thus preventing or improving these conditions. This article presents a mobile pressure ulcer monitoring platform (mULCER), which helps control a patient's ulcer status during all stages of treatment. Beside its stand-alone version, it can be integrated with electronic health record systems as mULCER synchronizes ulcer data with any electronic health record system using HL7 standards. It serves as a tool to integrate nursing care among hospital departments and institutions. mULCER was experimented with in different mobile devices such as LG Optimus One P500, Samsung Galaxy Tab, HTC Magic, Samsung Galaxy S, and Samsung Galaxy i5700, taking into account the user's experience of different screen sizes and processing characteristics.

Improved online δ18O measurements of nitrogen- and sulfur-bearing organic materials and a proposed analytical protocol

USGS Publications Warehouse

Qi, H.; Coplen, T.B.; Wassenaar, L.I.

2011-01-01

It is well known that N2 in the ion source of a mass spectrometer interferes with the CO background during the δ18O measurement of carbon monoxide. A similar problem arises with the high-temperature conversion (HTC) analysis of nitrogenous O-bearing samples (e.g. nitrates and keratins) to CO for δ18O measurement, where the sample introduces a significant N2 peak before the CO peak, making determination of accurate oxygen isotope ratios difficult. Although using a gas chromatography (GC) column longer than that commonly provided by manufacturers (0.6 m) can improve the efficiency of separation of CO and N2 and using a valve to divert nitrogen and prevent it from entering the ion source of a mass spectrometer improved measurement results, biased δ18O values could still be obtained. A careful evaluation of the performance of the GC separation column was carried out. With optimal GC columns, the δ18O reproducibility of human hair keratins and other keratin materials was better than ±0.15 ‰ (n = 5; for the internal analytical reproducibility), and better than ±0.10 ‰ (n = 4; for the external analytical reproducibility).

Mobile Learning Panel (Briefing Slides)

DTIC Science & Technology

2010-08-12

00-2010 4 . TITLE AND SUBTITLE Mobile Learning Panel 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...the Air Force and draw information from an enterprise knowledge base. • Self-paced individual training • Mandatory annual training • Classroom...iPhone • Sony Playstation Portable • Sony e-Reader • HTC, Palm, and Android CONTACT Leeescoemobile@conus.army.mil EVENT FACEBOOK Fort Lee

Cooperative Localization on Computationally Constrained Devices

DTIC Science & Technology

2012-03-22

Fi hotspot capability. The HTC phone is equipped with the Qualcomm MSM7200A chipset which includes support for 802.11 b/g, digital compass and...Chipset Specifications Wi-Fi Qualcomm MSM7200A +802.11 b/g Bluetooth Qualcomm MSM7200A -Version 2.0 + EDR Accelerometer Bosh BMA 150 +25-1500Hz...Magnetic Field Compensation GPS Qualcomm MSM7200A +Enhanced filtering software to optimize accuracy +gpsOneXTRA for enhanced standalone

Advancement and Implementation of Integrated Computational Materials Engineering (ICME) for Aerospace Applications

DTIC Science & Technology

2010-03-01

of sub-routines Thermal history • Abaqus FEM engine mature applied within ABAQUS Residual stress & Distortion • Unknown maturity for HTC • Focused...investment. The committee’s ICME vision is comprehensive, expansive , and involves the entire materials community. The scope of this white paper is...Software • Continuum FEM for fluid flow, heat Mold Fill • FEM implementation mature flow and stress analysis Thermal & mushy zone history • Needs

Technical description of space ultra reliable modular computer (SUMC), model 2 B

NASA Technical Reports Server (NTRS)

1975-01-01

The design features of the SUMC-2B computer, also called the IBM-HTC are described. It is general purpose digital computer implemented with flexible hardware elements and microprograming to enable low cost customizing to a wide range of applications. It executes the S/360 standard instruction set to maintain problem state compability. Memory technology, extended instruction sets, and I/O channel variations are among the available options.

Application of micronucleus test and comet assay to evaluate BTEX biodegradation.

PubMed

Mazzeo, Dânia Elisa Christofoletti; Matsumoto, Silvia Tamie; Levy, Carlos Emílio; de Angelis, Dejanira de Franceschi; Marin-Morales, Maria Aparecida

2013-01-01

The BTEX (benzene, toluene, ethylbenzene and xylene) mixture is an environmental pollutant that has a high potential to contaminate water resources, especially groundwater. The bioremediation process by microorganisms has often been used as a tool for removing BTEX from contaminated sites. The application of biological assays is useful in evaluating the efficiency of bioremediation processes, besides identifying the toxicity of the original contaminants. It also allows identifying the effects of possible metabolites formed during the biodegradation process on test organisms. In this study, we evaluated the genotoxic and mutagenic potential of five different BTEX concentrations in rat hepatoma tissue culture (HTC) cells, using comet and micronucleus assays, before and after biodegradation. A mutagenic effect was observed for the highest concentration tested and for its respective non-biodegraded concentration. Genotoxicity was significant for all non-biodegraded concentrations and not significant for the biodegraded ones. According to our results, we can state that BTEX is mutagenic at concentrations close to its water solubility, and genotoxic even at lower concentrations, differing from some described results reported for the mixture components, when tested individually. Our results suggest a synergistic effect for the mixture and that the biodegradation process is a safe and efficient methodology to be applied at BTEX-contaminated sites. Copyright © 2012 Elsevier Ltd. All rights reserved.

Developing and Benchmarking Native Linux Applications on Android

NASA Astrophysics Data System (ADS)

Batyuk, Leonid; Schmidt, Aubrey-Derrick; Schmidt, Hans-Gunther; Camtepe, Ahmet; Albayrak, Sahin

Smartphones get increasingly popular where more and more smartphone platforms emerge. Special attention was gained by the open source platform Android which was presented by the Open Handset Alliance (OHA) hosting members like Google, Motorola, and HTC. Android uses a Linux kernel and a stripped-down userland with a custom Java VM set on top. The resulting system joins the advantages of both environments, while third-parties are intended to develop only Java applications at the moment.

Breakdown of the Coulomb friction law in TiC/a-C:H nanocomposite coatings

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

Pei, Y. T.; Huizenga, P.; Galvan, D.

2006-12-01

Advanced TiC/a-C:H nanocomposite coatings have been produced via reactive deposition in a closed-field unbalanced magnetron sputtering system (Hauzer HTC-1000 or HTC 1200). In this paper, we report on the tribological behavior of TiC/a-C:H nanocomposite coatings in which ultralow friction is tailored with superior wear resistance, two properties often difficult to achieve simultaneously. Tribotests have been performed at room temperature with a ball-on-disk configuration. In situ monitoring of the wear depth of the coated disk together with the wear height of the ball counterpart at nanometer scale reveals that the self-lubricating effects are induced by the formation of transfer films onmore » the surface of the ball counterpart. A remarkable finding is a breakdown of the Coulomb friction law in the TiC/a-C:H nanocomposite coatings. In addition, the coefficient of friction of TiC/a-C:H nanocomposite coatings decreases with decreasing relative humidity. A superior wear resistance of the coated disk at a level of 10{sup -17} m{sup 3}/N m (per lap) has been achieved under the condition of superlow friction and high toughness, both of which require fine TiC nanoparticles (e.g., 2 nm) and a wide matrix separation that must be comparable to the dimensions of the nanoparticles.« less

Relative Risk Reduction as a Metric to Standardize Effect Size for Public Heath Interventions for Translational Research: Methods and Applications

PubMed Central

Mirzazadeh, A; Malekinejad, M; Kahn, JG

2018-01-01

Objective Heterogeneity of effect measures in intervention studies undermines the use of evidence to inform policy. Our objective was to develop a comprehensive algorithm to convert all types of effect measures to one standard metric, relative risk reduction (RRR). Study Design and Setting This work was conducted to facilitate synthesis of published intervention effects for our epidemic modeling of the health impact of HIV Testing and Counseling (HTC). We designed and implemented an algorithm to transform varied effect measures to RRR, representing the proportionate reduction in undesirable outcomes. Results Our extraction of 55 HTC studies identified 473 effect measures representing unique combinations of intervention-outcome-population characteristics, using five outcome metrics: pre-post proportion (70.6%), odds ratio (14.0%), mean difference (10.2%), risk ratio (4.4%), and RRR (0.9%). Outcomes were expressed as both desirable (29.5%, e.g., consistent condom use) and undesirable (70.5% e.g., inconsistent condom use). Using four examples, we demonstrate our algorithm for converting varied effect measures to RRR, and provide the conceptual basis for advantages of RRR over other metrics. Conclusion Our review of the literature suggests that RRR, an easily understood and useful metric to convey risk reduction associated with an intervention, is underutilized by original and review studies. PMID:25726522

Nesting of colon and ovarian cancer cells in the endothelial niche is associated with alterations in glycan and lipid metabolism

PubMed Central

Halama, Anna; Guerrouahen, Bella S.; Pasquier, Jennifer; Satheesh, Noothan J.; Suhre, Karsten; Rafii, Arash

2017-01-01

The metabolic phenotype of a cancer cell is determined by its genetic makeup and microenvironment, which dynamically modulates the tumor landscape. The endothelial cells provide both a promoting and protective microenvironment – a niche for cancer cells. Although metabolic alterations associated with cancer and its progression have been fairly defined, there is a significant gap in our understanding of cancer metabolism in context of its microenvironment. We deployed an in vitro co-culture system based on direct contact of cancer cells with endothelial cells (E4+EC), mimicking the tumor microenvironment. Metabolism of colon (HTC15 and HTC116) and ovarian (OVCAR3 and SKOV3) cancer cell lines was profiled with non-targeted metabolic approaches at different time points in the first 48 hours after co-culture was established. We found significant, coherent and non-cell line specific changes in fatty acids, glycerophospholipids and carbohydrates over time, induced by endothelial cell contact. The metabolic patterns pinpoint alterations in hexosamine biosynthetic pathway, glycosylation and lipid metabolism as crucial for cancer – endothelial cells interaction. We demonstrated that “Warburg effect” is not modulated in the initial stage of nesting of cancer cell in the endothelial niche. Our study provides novel insight into cancer cell metabolism in the context of the endothelial microenvironment. PMID:28051182

Evaluation of blood and serum markers in spinal cord injured patients with pressure sores.

PubMed

Gurcay, Eda; Bal, Ajda; Gurcay, Ahmet G; Cakci, Aytul

2009-03-01

To evaluate blood and serum markers in traumatic spinal cord injured (SCI) patients, with and without pressure sores. This cross-sectional study was performed at the Ministry of Health Diskapi Yildirim Beyazit, and Numune Education and Research Hospitals, Ankara, Turkey, from 2006-2008. A total of 23 SCI patients with pressure sores (group I) and a control group of 25 SCI patients without pressure sores (group II) were evaluated. Characteristics of sores were examined with respect to duration, location, grade, tissue types, surface area, and exudate amount. Recorded laboratory parameters included erythrocyte sedimentation rates (ESR), C-reactive protein (CRP), hemoglobin (Hb), hematocrit (Htc), lymphocytes, white blood cells (WBC), red blood cells (RBC), serum iron, transferrin, total iron-binding capacity (TIBC), ferritin, total protein, albumin, vitamin B12, and zinc. The most common pressure sore location was the sacrum (38%). Compared to the control group, the patients with pressure sores showed anemia with reduced serum iron, transferrin, TIBC, and increased ferritin. They also had increased ESR, CRP, and WBC and reduced lymphocytes, total protein, albumin and zinc. Statistically significant correlations were found between CRP, Hb, Htc, lymphocytes, RBC, WBC, and serum protein levels, and grade of pressure sores. Clinicians should regularly screen patients with respect to blood and serum markers, in order to determine any risks for pressure sores, and they should perform immediate preventive measures based on the patient's condition.

Comparing four service delivery models for adolescent girls and young women through the ‘Girl Power’ study: protocol for a multisite quasi-experimental cohort study

PubMed Central

Rosenberg, Nora E; Pettifor, Audrey E; Myers, Laura; Phanga, Twambilile; Marcus, Rebecca; Madlingozi, Nomtha; Vansia, Dhrutika; Masters, Avril; Maseko, Bertha; Mtwisha, Lulu; Kachigamba, Annie; Tang, Jennifer; Hosseinipour, Mina C; Bekker, Linda-Gail

2017-01-01

Introduction In sub-Saharan Africa, adolescent girls and young women (AGYW) face a range of sexual and reproductive health (SRH) challenges. Clinical, behavioural and structural interventions have each reduced these risks and improved health outcomes. However, combinations of these interventions have not been compared with each other or with no intervention at all. The ‘Girl Power’ study is designed to systematically make these comparisons. Methods and analysis Four comparable health facilities in Malawi and South Africa (n=8) were selected and assigned to one of the following models of care: (1) Standard of care: AGYW can receive family planning, HIV testing and counselling (HTC), and sexually transmitted infection (STI) syndromic management in three separate locations with three separate queues with the general population. No youth-friendly spaces, clinical modifications or trainings are offered, (2) Youth-Friendly Health Services (YFHS): AGYW are meant to receive integrated family planning, HTC and STI services in dedicated youth spaces with youth-friendly modifications and providers trained in YFHS, (3) YFHS+behavioural intervention (BI): In addition to YFHS, AGYW can attend 12 monthly theory-driven, facilitator-led, interactive sessions on health, finance and relationships, (4) YFHS+BI+conditional cash transfer (CCT): in addition to YFHS and BI, AGYW receive up to 12 CCTs conditional on monthly BI session attendance. At each clinic, 250 AGYW 15–24 years old (n=2000 total) will be consented, enrolled and followed for 1 year. Each participant will complete a behavioural survey at enrolment, 6 months and 12 months . All clinical, behavioural and CCT services will be captured. Outcomes of interest include uptake of each package element and reduction in HIV risk behaviours. A qualitative substudy will be conducted. Ethics/dissemination This study has received ethical approval from the University of North Carolina Institutional Review Board, the University of Cape Town Human Research Ethics Committee and Malawi’s National Health Sciences Research Committee. Study plans, processes and findings will be disseminated to stakeholders, in peer-reviewed journals and at conferences. PMID:29247104

Integrated planning and scheduling for Earth science data processing

NASA Technical Reports Server (NTRS)

Boddy, Mark; White, Jim; Goldman, Robert; Short, Nick, Jr.

1995-01-01

Several current NASA programs such as the EOSDIS Core System (ECS) have data processing and data management requirements that call for an integrated planning and scheduling capability. In this paper, we describe the experience of applying advanced scheduling technology operationally, in terms of what was accomplished, lessons learned, and what remains to be done in order to achieve similar successes in ECS and other programs. We discuss the importance and benefits of advanced scheduling tools, and our progress toward realizing them, through examples and illustrations based on ECS requirements. The first part of the paper focuses on the Data Archive and Distribution (DADS) V0 Scheduler. We then discuss system integration issues ranging from communication with the scheduler to the monitoring of system events and re-scheduling in response to them. The challenge of adapting the scheduler to domain-specific features and scheduling policies is also considered. Extrapolation to the ECS domain raises issues of integrating scheduling with a product-generation planner (such as PlaSTiC), and implementing conditional planning in an operational system. We conclude by briefly noting ongoing technology development and deployment projects being undertaken by HTC and the ISTB.

Influence of pH on hydrothermal treatment of swine manure: Impact on extraction of nitrogen and phosphorus in process water.

PubMed

Ekpo, U; Ross, A B; Camargo-Valero, M A; Fletcher, L A

2016-08-01

This study investigates the influence of pH on extraction of nitrogen and phosphorus from swine manure following hydrothermal treatment. Conditions include thermal hydrolysis (TH) at 120°C and 170°C, and hydrothermal carbonisation (HTC) at 200°C and 250°C in either water alone or in the presence of 0.1M NaOH, H2SO4, CH3COOH or HCOOH. Phosphorus extraction is pH and temperature dependent and is enhanced under acidic conditions. The highest level of phosphorus is extracted using H2SO4 reaching 94% at 170°C. The phosphorus is largely retained in the residue for all other conditions. The extraction of nitrogen is not as significantly influenced by pH, although the maximum N extraction is achieved using H2SO4. A significant level of organic-N is extracted into the process waters following hydrothermal treatment. The results indicate that operating hydrothermal treatment in the presence of acidic additives has benefits in terms of improving the extraction of phosphorus and nitrogen. Copyright © 2016. Published by Elsevier Ltd.

Cytotoxic and mutagenic effects of iodine-131 and radioprotection of acerola (Malpighia glabra L.) and beta-carotene in vitro.

PubMed

Almeida, I V; Düsman, E; Heck, M C; Pamphile, J A; Lopes, N B; Tonin, L T D; Vicentini, V E P

2013-12-10

The radioisotope iodine-131 [(131)I] can damage DNA. One way to prevent this is to increase the amount of antioxidants via dietary consumption. The goal of this study was to evaluate the radioprotective effect of fresh acerola pulp and synthetic beta-carotene in Rattus norvegicus hepatoma cells (HTC) in response to [(131)I] exposure in vitro. Cellular DNA damage was subsequently assessed using a cytokinesis block micronucleus assay. The mutagenic and cytotoxic activities of doses of [(131)I] (0.1, 0.5, 1, 5, and 10 µCi), acerola (0.025, 0.125, and 0.25 g acerola pulp/mL), and beta-carotene (0.2, 1, and 2 µM) were evaluated. Radioprotective tests were performed by simultaneous treatment with acerola (0.25 g/mL) plus [(131)I] (10 µCi) and beta-carotene (0.2 µM) plus [(131)I] (10 µCi). Acerola, beta-carotene, and low concentrations of [(131)I] did not induce micronucleus formation in HTC cells; in contrast, high concentrations of [(131)I] (10 µCi) were mutagenic and induced DNA damage. Moreover, neither acerola nor beta-carotene treatment was cytotoxic. However, acerola reduced the percentage of [(131)I]-induced damage, although beta-carotene did not show a similar effect. Thus, our results suggest that acerola diet supplementation may benefit patients who are exposed to [(131)I] during thyroid diagnostics and therapy.

Heat and Freshwater Convergence Anomalies in the Atlantic Ocean Inferred from Observations

NASA Astrophysics Data System (ADS)

Kelly, K. A.; Drushka, K.; Thompson, L.

2015-12-01

Observations of thermosteric and halosteric sea level from hydrographic data, ocean mass from GRACE and altimetric sea surface height are used to infer meridional heat transport (MHT) and freshwater convergence (FWC) anomalies for the Atlantic Ocean. An "unknown control" version of a Kalman filter in each of eight regions extracts smooth estimates of heat transport convergence (HTC) and FWC from discrepancies between the sea level response to monthly surface heat and freshwater fluxes and observed heat and freshwater content. The model is run for 1993-2014. Estimates of MHT anomalies are derived by summing the HTC from north to south and adding a spatially uniform, time-varying MHT derived from updated MHT estimates at 41N (Willis 2010). Estimated anomalies in MHT are comparable to those recently observed at the RAPID/MOCHA line at 26.5N. MHT estimates are relatively insensitive to the choice of heat flux products and are highly coherent spatially. MHT anomalies at 35S resemble estimates of Agulhas Leakage derived from altimeter (LeBars et al 2014) suggesting that the Indian Ocean is the source of the anomalous heat inflow. FWC estimates in the Atlantic Ocean (67N to 35S) resemble estimates of Atlantic river inflow (de Couet and Maurer, GRDC 2009). Increasing values of FWC after 2002 at a time when MHT was decreasing may indicate a feedback between the Atlantic Meridional Overturning Circulation and FWC that would accelerate the AMOC slowdown.

The microscale cooling effects of water sensitive urban design and irrigation in a suburban environment

NASA Astrophysics Data System (ADS)

Broadbent, Ashley M.; Coutts, Andrew M.; Tapper, Nigel J.; Demuzere, Matthias; Beringer, Jason

2017-09-01

Prolonged drought has threatened traditional potable urban water supplies in Australian cities, reducing capability to adapt to climate change and mitigate against extreme. Integrated urban water management (IUWM) approaches, such as water sensitive urban design (WSUD), reduce the reliance on centralised potable water supply systems and provide a means for retaining water in the urban environment through stormwater harvesting and reuse. This study examines the potential for WSUD to provide cooling benefits and reduce human exposure and heat stress and thermal discomfort. A high-resolution observational field campaign, measuring surface level microclimate variables and remotely sensed land surface characteristics, was conducted in a mixed residential suburb containing WSUD in Adelaide, South Australia. Clear evidence was found that WSUD features and irrigation can reduce surface temperature (T s) and air temperature (T a) and improve human thermal comfort (HTC) in urban environments. The average 3 pm T a near water bodies was found to be up to 1.8 °C cooler than the domain maximum. Cooling was broadly observed in the area 50 m downwind of lakes and wetlands. Design and placement of water bodies were found to affect their cooling effectiveness. HTC was improved by proximity to WSUD features, but shading and ventilation were also effective at improving thermal comfort. This study demonstrates that WSUD can be used to cool urban microclimates, while simultaneously achieving other environmental benefits, such as improved stream ecology and flood mitigation.

Genetic polymorphisms within exon 3 of heat shock protein 90AA1 gene and its association with heat tolerance traits in Sahiwal cows

PubMed Central

Kumar, Rakesh; Gupta, I. D.; Verma, Archana; Verma, Nishant; Vineeth, M. R.

2015-01-01

Aim: The present study was undertaken to identify novel single nucleotide polymorphism (SNP) in Exon 3 of HSP90AA1 gene and to analyze their association with respiration rate (RR) and rectal temperature (RT) in Sahiwal cows. Materials and Methods: The present study was carried out in Sahiwal cows (n=100) with the objectives to identify novel SNP in exon 3 of HSP90AA1 gene and to explore the association with heat tolerance traits. CLUSTAL-W multiple sequence analysis was used to identify novel SNPs in exon 3 of HSP90AA1 gene in Sahiwal cows. Gene and genotype frequencies of different genotypes were estimated by standard procedure POPGENE version 1.32 (University of Alberta, Canada). The significant effect of SNP variants on physiological parameters, e.g. RR and RT were analyzed using the General Linear model procedure of SAS Version 9.2. Results: The polymerase chain reaction product with the amplicon size of 450 bp was successfully amplified, covering exon 3 region of HSP90AA1 gene in Sahiwal cows. On the basis of comparative sequence analysis of Sahiwal samples (n=100), transitional mutations were detected at locus A1209G as compared to Bos taurus (NCBI GenBank AC_000178.1). After chromatogram analysis, three genotypes AA, AG, and GG with respective frequencies of 0.23, 0.50, and 0.27 ascertained. RR and RT were recorded once during probable extreme hours in winter, spring, and summer seasons. It was revealed that significant difference (p<0.01) among genetic variants of HSP90AA1 gene with heat tolerance trait was found in Sahiwal cattle. The homozygotic animals with AA genotype had lower heat tolerance coefficient (HTC) (1.78±0.04a), as compared to both AG and GG genotypes (1.85±0.03b and 1.91±0.02c), respectively. The gene and genotype frequencies for the locus A1209G were ascertained. Conclusions: Novel SNP was found at the A1209G position showed all possible three genotypes (homozygous and heterozygous). Temperature humidity index has a highly significant association with RR, RT, and HTC in all the seasons. Perusal of results across different seasons showed the significant (p<0.01) difference in RR, RT, and HTC among winter, spring, and summer seasons. Genetic association with heat tolerance traits reveals their importance as a potential genetic marker for heat tolerance traits in Sahiwal cows. PMID:27047179

8. Innovative Technologies: Two-Phase Heat Transfer in Water-Based Nanofluids for Nuclear Applications Final Report

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

Buongiorno, Jacopo; Hu, Lin-wen

2009-07-31

Nanofluids are colloidal dispersions of nanoparticles in water. Many studies have reported very significant enhancement (up to 200%) of the Critical Heat Flux (CHF) in pool boiling of nanofluids (You et al. 2003, Vassallo et al. 2004, Bang and Chang 2005, Kim et al. 2006, Kim et al. 2007). These observations have generated considerable interest in nanofluids as potential coolants for more compact and efficient thermal management systems. Potential Light Water Reactor applications include the primary coolant, safety systems and severe accident management strategies, as reported in other papers (Buongiorno et al. 2008 and 2009). However, the situation of interestmore » in reactor applications is often flow boiling, for which no nanofluid data have been reported so far. In this project we investigated the potential of nanofluids to enhance CHF in flow boiling. Subcooled flow boiling heat transfer and CHF experiments were performed with low concentrations of alumina, zinc oxide, and diamond nanoparticles in water (≤ 0.1 % by volume) at atmospheric pressure. It was found that for comparable test conditions the values of the nanofluid and water heat transfer coefficient (HTC) are similar (within ±20%). The HTC increased with mass flux and heat flux for water and nanofluids alike, as expected in flow boiling. The CHF tests were conducted at 0.1 MPa and at three different mass fluxes (1500, 2000, 2500 kg/m2s) under subcooled conditions. The maximum CHF enhancement was 53%, 53% and 38% for alumina, zinc oxide and diamond, respectively, always obtained at the highest mass flux. A post-mortem analysis of the boiling surface reveals that its morphology is altered by deposition of the particles during nanofluids boiling. A confocal-microscopy-based examination of the test section revealed that nanoparticles deposition not only changes the number of micro-cavities on the surface, but also the surface wettability. A simple model was used to estimate the ensuing nucleation site density changes, but no definitive correlation between the nucleation site density and the heat transfer coefficient data could be found. Wettability of the surface was substantially increased for heater coupons boiled in alumina and zinc oxide nanofluids, and such wettability increase seems to correlate reasonably well with the observed marked CHF enhancement for the respective nanofluids. Interpretation of the experimental data was conducted in light of the governing surface parameters (surface area, contact angle, roughness, thermal conductivity) and existing models. It was found that no single parameter could explain the observed HTC or CHF phenomena.« less

Estimated age and gender profile of individuals missed by a home-based HIV testing and counselling campaign in a Botswana community.

PubMed

Novitsky, Vlad; Bussmann, Hermann; Okui, Lillian; Logan, Andrew; Moyo, Sikhulile; van Widenfelt, Erik; Mmalane, Mompati; Lei, Quanhong; Holme, Molly P; Makhema, Joseph; Lockman, Shahin; Degruttola, Victor; Essex, M

2015-01-01

It would be useful to understand which populations are not reached by home-based HIV-1 testing and counselling (HTC) to improve strategies aimed at linking these individuals to care and reducing rates of onward HIV transmission. We present the results of a baseline home-based HTC (HBHTC) campaign aimed at counselling and testing residents aged 16 to 64 for HIV in the north-eastern sector of Mochudi, a community in Botswana with about 44,000 inhabitants. Collected data were compared with population references for Botswana, the United Nations (UN) estimates based on the National Census data and the Botswana AIDS Impact Survey IV (BAIS-IV). Analyzed data and references were stratified by age and gender. A total of 6238 age-eligible residents were tested for HIV-1; 1247 (20.0%; 95% CI 19.0 to 21.0%) were found to be HIV positive (23.7% of women vs. 13.4% of men). HIV-1 prevalence peaked at 44% in 35- to 39-year-old women and 32% in 40- to 44-year-old men. A lower HIV prevalence rate, 10.9% (95% CI 9.5 to 12.5%), was found among individuals tested for the first time. A significant gender gap was evident in all analyzed subsets. The existing HIV transmission network was analyzed by combining phylogenetic mapping and household structure. Between 62.4 and 71.8% of all HIV-positive individuals had detectable virus. When compared with the UN and BAIS-IV estimates, the proportion of men missed by the testing campaign (48.5%; 95% CI 47.0 to 50.0%) was significantly higher than the proportion of missed women (14.2%; 95% CI 13.2 to 15.3%; p<0.0001). The estimated proportion of missed men peaked at about 60% in the age group 30 to 39 years old. The proportions of missed women were substantially smaller, at approximately 28% within the age groups 30 to 34 and 45 to 49 years old. The HBHTC campaign seems to be an efficient tool for reaching individuals who have never been tested previously in southern African communities. However, about half of men from 16 to 64 years old were not reached by the HBHTC, including about 60% of men between 30 and 40 years old. Alternative HTC strategies should be developed to bring these men to care, which will contribute to reduction of HIV incidence in communities.

Formation of hydrothermal biochar and char stability in soils

NASA Astrophysics Data System (ADS)

Baumert, Julia; Gleixner, Gerd

2010-05-01

The use of charcoal as an artificial soil additive is suggested to beneficially modify degraded soil, reduce greenhouse gas emission and improve crop yields. So far research has been mainly done using pyrolysis chars which are produced by dry pyrolysis of biomass. Here we used hydrothermal carbonisation (HTC). In this process wet biomass is converted to char at moderate temperatures (~200°C). Due to the exothermal carbonisation reaction this process is almost energy neutral, i.e. the energy needed to start the carbonisation equals the energy released during carbonisation. Different process parameters have been used to modify the properties of the produced chars. We examined the chemical and morphological properties of hydrothermally synthesized biochar. Cellulose, yeast and sucrose were used as model substances for a range of parent material types like organic and garden waste as well as residues from biogas production. By modifying the process conditions of hydrothermal carbonisation concerning temperature (180°C to 220°C) and duration (6 hours to 24 hours) we produced a variety of different biochars. Our findings suggest that the elemental composition and the thermal stability of resulting chars depend on the feedstock and production conditions. Functional group chemistry determined by NMR shows that the aromaticity of the product increases as a function of temperature whereas the amount of O-alkylic compounds declines, concurrently. Our results show that the properties of the biochar can be manipulated by the modification of process conditions. This opens the opportunity to adjust the charcoal to a given soil type.

A Simple and Resource-efficient Setup for the Computer-aided Drug Design Laboratory.

PubMed

Moretti, Loris; Sartori, Luca

2016-10-01

Undertaking modelling investigations for Computer-Aided Drug Design (CADD) requires a proper environment. In principle, this could be done on a single computer, but the reality of a drug discovery program requires robustness and high-throughput computing (HTC) to efficiently support the research. Therefore, a more capable alternative is needed but its implementation has no widespread solution. Here, the realization of such a computing facility is discussed, from general layout to technical details all aspects are covered. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Research on and Application to BH-HTC High Density Cementing Slurry System on Tarim Region

NASA Astrophysics Data System (ADS)

Yuanhong, Song; Fei, Gao; Jianyong, He; Qixiang, Yang; Jiang, Yang; Xia, Liu

2017-08-01

A large section of salt bed is contented in Tarim region Piedmont which constructs complex geological conditions. For high-pressure gas well cementing difficulties from the region, high density cement slurry system has been researched through reasonable level of particle size distribution and second weighting up. The results of laboratory tests and field applications show that the high density cementing slurry system is available to Tarim region cementing because this system has a well performance in slurry stability, gas breakthrough control, fluidity, water loss, and strength.

Hermes: Seamless delivery of containerized bioinformatics workflows in hybrid cloud (HTC) environments

NASA Astrophysics Data System (ADS)

Kintsakis, Athanassios M.; Psomopoulos, Fotis E.; Symeonidis, Andreas L.; Mitkas, Pericles A.

Hermes introduces a new "describe once, run anywhere" paradigm for the execution of bioinformatics workflows in hybrid cloud environments. It combines the traditional features of parallelization-enabled workflow management systems and of distributed computing platforms in a container-based approach. It offers seamless deployment, overcoming the burden of setting up and configuring the software and network requirements. Most importantly, Hermes fosters the reproducibility of scientific workflows by supporting standardization of the software execution environment, thus leading to consistent scientific workflow results and accelerating scientific output.

HIV status awareness, partnership dissolution and HIV transmission in generalized epidemics.

PubMed

Reniers, Georges; Armbruster, Benjamin

2012-01-01

HIV status aware couples with at least one HIV positive partner are characterized by high separation and divorce rates. This phenomenon is often described as a corollary of couples HIV Testing and Counseling (HTC) that ought to be minimized. In this contribution, we demonstrate the implications of partnership dissolution in serodiscordant couples for the propagation of HIV. We develop a compartmental model to study epidemic outcomes of elevated partnership dissolution rates in serodiscordant couples and parameterize it with estimates from population-based data (Rakai, Uganda). Via its effect on partnership dissolution, every percentage point increase in HIV status awareness reduces HIV incidence in monogamous populations by 0.27 percent for women and 0.63 percent for men. These effects are even larger when the assumption of monogamy can be relaxed, but are moderated by other behavior changes (e.g., increased condom use) in HIV status aware serodiscordant partnerships. When these behavior changes are taken into account, each percentage point increase in HIV status awareness reduces HIV incidence by 0.13 and 0.32 percent for women and men, respectively (assuming monogamy). The partnership dissolution effect exists because it decreases the fraction of serodiscordant couples in the population and prolongs the time that individuals spend outside partnerships. Our model predicts that elevated partnership dissolution rates in HIV status aware serodiscordant couples reduce the spread of HIV. As a consequence, the full impact of couples HTC for HIV prevention is probably larger than recognized to date. Particularly high partnership dissolution rates in female positive serodiscordant couples contribute to the gender imbalance in HIV infections.

Mercury tissue residue approach in Chironomus riparius: Involvement of toxicokinetics and comparison of subcellular fractionation methods.

PubMed

Gimbert, Frédéric; Geffard, Alain; Guédron, Stéphane; Dominik, Janusz; Ferrari, Benoit J D

2016-02-01

Along with the growing body of evidence that total internal concentration is not a good indicator of toxicity, the Critical Body Residue (CBR) approach recently evolved into the Tissue Residue Approach (TRA) which considers the biologically active portion of metal that is available to contribute to the toxicity at sites of toxic action. For that purpose, we examined total mercury (Hg) bioaccumulation and subcellular fractionation kinetics in fourth stage larvae of the midge Chironomus riparius during a four-day laboratory exposure to Hg-spiked sediments and water. The debris (including exoskeleton, gut contents and cellular debris), granule and organelle fractions accounted only for about 10% of the Hg taken up, whereas Hg concentrations in the entire cytosolic fraction rapidly increased to approach steady-state. Within this fraction, Hg compartmentalization to metallothionein-like proteins (MTLP) and heat-sensitive proteins (HSP), consisting mostly of enzymes, was assessed in a comparative manner by two methodologies based on heat-treatment and centrifugation (HT&C method) or size exclusion chromatography separation (SECS method). The low Hg recoveries obtained with the HT&C method prevented accurate analysis of the cytosolic Hg fractionation by this approach. According to the SECS methodology, the Hg-bound MTLP fraction increased linearly over the exposure duration and sequestered a third of the Hg flux entering the cytosol. In contrast, the HSP fraction progressively saturated leading to Hg excretion and physiological impairments. This work highlights several methodological and biological aspects to improve our understanding of Hg toxicological bioavailability in aquatic invertebrates. Copyright © 2015 Elsevier B.V. All rights reserved.

Sources of Meridional Heat and Freshwater Transport Anomalies in the Atlantic Ocean

NASA Astrophysics Data System (ADS)

Kelly, K. A.; Thompson, L.; Drushka, K.

2016-02-01

Observations of thermosteric and halosteric sea level from hydrographic data, ocean mass from GRACE and altimetric sea surface height are used to infer meridional heat transport (MHT) and freshwater convergence (FWC) anomalies for the Atlantic Ocean for 1993-2014. A Kalman filter extracts smooth estimates of heat transport convergence (HTC) and FWC from discrepancies between the sea level response to monthly surface heat and freshwater fluxes and observed heat and freshwater content in each of eight regions. Estimates of MHT anomalies are derived by summing the HTC from north to south and adding an integration constant derived from updated MHT estimates at 41N (Willis 2010). MHT estimates are relatively insensitive to the choice of heat flux products and are highly coherent spatially. Anomalies in MHT are comparable to those observed at the RAPID/MOCHA line at 26.5N and show a continued recovery from the minimum in 2010 throughout the Atlantic. MHT anomalies resemble estimates of Agulhas Leakage derived from altimeter (LeBars et al 2014) suggesting that the Indian Ocean is the source of the anomalous heat inflow. FWC estimates are also insensitive to choice of flux products. Interannual anomalies of FWC integrated from 67N to 35S resemble estimates of Atlantic river inflow (de Couet and Maurer, GRDC 2009), whereas the trend is consistent with estimates of freshwater input from Greenland. Increasing values of FWC after 2002 at a time when MHT was decreasing may indicate a feedback between the Atlantic Meridional Overturning Circulation and FWC that would accelerate the AMOC slowdown.

Rigorous theory of graded thermoelectric converters including finite heat transfer coefficients

NASA Astrophysics Data System (ADS)

Gerstenmaier, York Christian; Wachutka, Gerhard

2017-11-01

Maximization of thermoelectric (TE) converter performance with an inhomogeneous material and electric current distribution has been investigated in previous literature neglecting thermal contact resistances to the heat reservoirs. The heat transfer coefficients (HTCs), defined as inverse thermal contact resistances per unit area, are thus infinite, whereas in reality, always parasitic thermal resistances, i.e., finite HTCs, are present. Maximization of the generated electric power and of cooling power in the refrigerator mode with respect to Seebeck coefficients and heat conductivity for a given profile of the material's TE figure of merit Z are mathematically ill-posed problems in the presence of infinite HTCs. As will be shown in this work, a fully self consistent solution is possible for finite HTCs, and in many respects, the results are fundamentally different. A previous theory for 3D devices will be extended to include finite HTCs and is applied to 1D devices. For the heat conductivity profile, an infinite number of solutions exist leading to the same device performance. Cooling power maximization for finite HTCs in 1D will lead to a strongly enhanced corresponding efficiency (coefficient of performance), whereas results with infinite HTCs lead to a non-monotonous temperature profile and coefficient of performance tending to zero for the prescribed heat conductivities. For maximized generated electric power, the corresponding generator efficiency is nearly a constant independent from the finite HTC values. The maximized efficiencies in the generator and cooling mode are equal to the efficiencies for the infinite HTC, provided that the corresponding powers approach zero. These and more findings are condensed in 4 theorems in the conclusions.

A study of prospective surveillance for inhibitors among persons with haemophilia in the United States.

PubMed

Soucie, J M; Miller, C H; Kelly, F M; Payne, A B; Creary, M; Bockenstedt, P L; Kempton, C L; Manco-Johnson, M J; Neff, A T

2014-03-01

Inhibitors are a rare but serious complication of treatment of patients with haemophilia. Phase III clinical trials enrol too few patients to adequately assess new product inhibitor risk. This project explores the feasibility of using a public health surveillance system to conduct national surveillance for inhibitors. Staff at 17 U.S. haemophilia treatment centres (HTC) enrolled patients with haemophilia A and B into this prospective study. HTC staff provided detailed historic data on product use and inhibitors at baseline, and postenrolment patients provided monthly detailed infusion logs. A central laboratory performed inhibitor tests on blood specimens that were collected at baseline, annually, prior to any planned product switch or when clinically indicated. The central laboratory also performed genotyping of all enrolled patients. From January 2006 through June 2012, 1163 patients were enrolled and followed up for 3329 person-years. A total of 3048 inhibitor tests were performed and 23 new factor VIII inhibitors were identified, 61% of which were not clinically apparent. Infusion logs were submitted for 113,205 exposure days. Genotyping revealed 431 distinct mutations causing haemophilia, 151 of which had not previously been reported elsewhere in the world. This study provided critical information about the practical issues that must be addressed to successfully implement national inhibitor surveillance. Centralized testing with routine monitoring and confirmation of locally identified inhibitors will provide valid and representative data with which to evaluate inhibitor incidence and prevalence, monitor trends in occurrence rates and identify potential inhibitor outbreaks associated with products. © 2013 John Wiley & Sons Ltd.

Entorhinal theta-frequency input to the dentate gyrus trisynaptically evokes hippocampal CA1 LTP

PubMed Central

Stepan, Jens; Dine, Julien; Fenzl, Thomas; Polta, Stephanie A.; von Wolff, Gregor; Wotjak, Carsten T.; Eder, Matthias

2012-01-01

There exists substantial evidence that some forms of explicit learning in mammals require long-term potentiation (LTP) at hippocampal CA3-CA1 synapses. While CA1 LTP has been well characterized at the monosynaptic level, it still remains unclear how the afferent systems to the hippocampus can initiate formation of this neuroplastic phenomenon. Using voltage-sensitive dye imaging (VSDI) in a mouse brain slice preparation, we show that evoked entorhinal cortical (EC) theta-frequency input to the dentate gyrus highly effectively generates waves of neuronal activity which propagate through the entire trisynaptic circuit of the hippocampus (“HTC-Waves”). This flow of activity, which we also demonstrate in vivo, critically depends on frequency facilitation of mossy fiber to CA3 synaptic transmission. The HTC-Waves are rapidly boosted by the cognitive enhancer caffeine (5 μM) and the stress hormone corticosterone (100 nM). They precisely follow the rhythm of the EC input, involve high-frequency firing (>100 Hz) of CA3 pyramidal neurons, and induce NMDA receptor-dependent CA1 LTP within a few seconds. Our study provides the first experimental evidence that synchronous theta-rhythmical spiking of EC stellate cells, as occurring during EC theta oscillations, has the capacity to drive induction of CA1 LTP via the hippocampal trisynaptic pathway. Moreover, we present data pointing to a basic filter mechanism of the hippocampus regarding EC inputs and describe a methodology to reveal alterations in the “input–output relationship” of the hippocampal trisynaptic circuit. PMID:22988432

Comparing four service delivery models for adolescent girls and young women through the 'Girl Power' study: protocol for a multisite quasi-experimental cohort study.

PubMed

Rosenberg, Nora E; Pettifor, Audrey E; Myers, Laura; Phanga, Twambilile; Marcus, Rebecca; Bhushan, Nivedita Latha; Madlingozi, Nomtha; Vansia, Dhrutika; Masters, Avril; Maseko, Bertha; Mtwisha, Lulu; Kachigamba, Annie; Tang, Jennifer; Hosseinipour, Mina C; Bekker, Linda-Gail

2017-12-14

In sub-Saharan Africa, adolescent girls and young women (AGYW) face a range of sexual and reproductive health (SRH) challenges. Clinical, behavioural and structural interventions have each reduced these risks and improved health outcomes. However, combinations of these interventions have not been compared with each other or with no intervention at all. The 'Girl Power' study is designed to systematically make these comparisons. Four comparable health facilities in Malawi and South Africa (n=8) were selected and assigned to one of the following models of care: (1) Standard of care : AGYW can receive family planning, HIV testing and counselling (HTC), and sexually transmitted infection (STI) syndromic management in three separate locations with three separate queues with the general population. No youth-friendly spaces, clinical modifications or trainings are offered, (2) Youth-Friendly Health Services (YFHS) : AGYW are meant to receive integrated family planning, HTC and STI services in dedicated youth spaces with youth-friendly modifications and providers trained in YFHS, (3) YFHS+behavioural intervention (BI) : In addition to YFHS, AGYW can attend 12 monthly theory-driven, facilitator-led, interactive sessions on health, finance and relationships, (4) YFHS+BI+conditional cash transfer (CCT) : in addition to YFHS and BI, AGYW receive up to 12 CCTs conditional on monthly BI session attendance.At each clinic, 250 AGYW 15-24 years old (n=2000 total) will be consented, enrolled and followed for 1 year. Each participant will complete a behavioural survey at enrolment, 6 months and 12 months . All clinical, behavioural and CCT services will be captured. Outcomes of interest include uptake of each package element and reduction in HIV risk behaviours. A qualitative substudy will be conducted. This study has received ethical approval from the University of North Carolina Institutional Review Board, the University of Cape Town Human Research Ethics Committee and Malawi's National Health Sciences Research Committee. Study plans, processes and findings will be disseminated to stakeholders, in peer-reviewed journals and at conferences. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Environmental Impacts of the Production and Application of Biochar - EuroChar Project

NASA Astrophysics Data System (ADS)

Rack, Mireille; Woods, Jeremy

2014-05-01

One of the potential benefits of biochar is carbon sequestration. To determine the overall net sequestration potential it is important to analyse the full supply chain, assessing both the direct and indirect emissions associated with the production and application of biochar. However, it is essential to also incorporate additional environmental impact categories to ensure the assessment of a more complete environmental impact profile. This paper uses a full life-cycle assessment (LCA) methodology to evaluate the results from the EuroChar, 'biochar for carbon sequestration and large-scale removal of GHG from the atmosphere', project. This EU Seventh Framework Programme project aims to investigate and reduce uncertainties around the impacts of, and opportunities for, biochar, and in particular explore possible pathways for its introduction into modern agricultural systems in Europe. The LCA methodology, according to the ISO standards, is applied to the project-specific supply chains to analyse the environmental impacts of biochar production and application. Two conversion technologies for the production of biochar are assessed, gasification and hydrothermal carbonization (HTC), in order to provide conversion efficiencies and emission factors for the biochar production component of the supply chain. The selected feedstocks include those derived from waste residues and dedicated crops. For the end use stage, various forms and methods for biochar application are considered. In addition to the Global Warming Potential category, other environmental impact categories are also included in the analysis. The resulting 'feedstock * conversion technology' matrix provides nine pathways for the production and application of biochar, which are applied as a representative basis for the scenario modelling. These scenarios have been developed in order to assess the feedstock and land availability in Europe for the production and application of biochar and to give an order of magnitude assessment as to the potential role for biochar as a material climate mitigation option. Preliminary results show net negative supply chain emissions, indicating biochar to be a carbon sink. Overall, the life cycle stage that contributes most significantly to the environmental impact profile is feedstock production. Feedstock selection is therefore expected to play a key role in determining the overall viability of biochar production and its use in land application. Further sensitivity analyses show that the allocation method of the attributional LCA has the greatest impact on the results, followed by the oxidation rate of the carbon in the biochar, and the transportation distances of the feedstock and biochar. Indirect impacts, such as avoided use of fossil fuel, can significantly alter the results. As the EuroChar project comes to a completion at the end of May 2014, the near-final results are presented at the EGU 2014 General Assembly.

Complex Actions of Thyroid Hormone Receptor Antagonist NH-3 on Gene Promoters in Different Cell Lines

PubMed Central

Shah, Vanya; Nguyen, Phuong; Nguyen, Ngoc-Ha; Togashi, Marie; Scanlan, Thomas S.; Baxter, John D.; Webb, Paul

2014-01-01

It is desirable to obtain new antagonists for thyroid hormone (TRs) and other nuclear receptors (NRs). We previously used X-ray structural models of TR ligand binding domains (LBDs) to design compounds, such as NH-3, that impair coactivator binding to activation function 2 (AF-2) and block thyroid hormone (triiodothyronine, T3) actions. However, TRs bind DNA and are transcriptionally active without ligand. Thus, NH-3 could modulate TR activity via effects on other coregulator interaction surfaces, such as activation function (AF-1) and corepressor binding sites. Here, we find that NH-3 blocks TR-LBD interactions with coactivators and corepressors and also inhibits activities of AF-1 and AF-2 in transfections. While NH-3 lacks detectable agonist activity at T3-activated genes in GC pituitary cells it nevertheless activates spot 14 (S14) in HTC liver cells with the latter effect accompanied by enhanced histone H4 acetylation and coactivator recruitment at the S14 promoter. Surprisingly, T3 promotes corepressor recruitment to target promoters. NH-3 effects vary; we observe transient recruitment of N-CoR to S14 in GC cells and dismissal and rebinding of N-CoR to the same promoter in HTC cells. We propose that NH-3 will generally behave as an antagonist by blocking AF-1 and AF-2 but that complex effects on coregulator recruitment may result in partial/mixed agonist effects that are independent of blockade of T3 binding in some contexts. These properties could ultimately be utilized in drug design and development of new selective TR modulators. PMID:18930112

Polymorphisms in the bovine HSP90AB1 gene are associated with heat tolerance in Thai indigenous cattle.

PubMed

Charoensook, Rangsun; Gatphayak, Kesinee; Sharifi, Ahmad Reza; Chaisongkram, Chavin; Brenig, Bertram; Knorr, Christoph

2012-04-01

Heat shock proteins act as molecular chaperones that have preferentially been transcribed in response to severe perturbations of the cellular homeostasis such as heat stress. Here the traits respiration rate (RR), rectal temperature (RT), pack cell volume (PCV) and the individual heat tolerance coefficient (HTC) were recorded as physiological responses on heat stress (environmental temperatures) in Bos taurus (crossbred Holstein Friesian; HF) and B. indicus (Thai native cattle: White Lamphun; WL and Mountain cattle; MT) animals (n = 47) in Thailand. Polymorphisms of the heat shock protein 90-kDa beta gene (HSP90AB1) were evaluated by comparative sequencing. Nine single nucleotide polymorphisms (SNP) were identified, i.e. three in exons 10 and 11, five in introns 8, 9, 10 and 11, and one in the 3'UTR. The exon 11 SNP g.5082C>T led to a missense mutation (alanine to valine). During the period of extreme heat (in the afternoon) RR and RT were elevated in each of the three breeds, whereas the PCV decreased. Mountain cattle and White Lamphun heifers recorded significantly better physiologic parameters (p < 0.05) in all traits considered, including or particularly HTC than Holstein Friesian heifers. The association analysis revealed that the T allele at SNP g.4338T>C within intron 3 improved the heat tolerance (p < 0.05). Allele T was exclusively found in White Lamphun animals and to 84% in Mountain cattle. Holstein Friesian heifers revealed an allele frequency of only 18%. Polymorphisms within HSP90AB1 were not causative for the physiological responses; however, we propose that they should at least be used as genetic markers to select appropriate breeds for hot climates.

Differentiation of a Highly Tumorigenic Basal Cell Compartment in Urothelial Carcinoma

PubMed Central

He, Xiaobing; Marchionni, Luigi; Hansel, Donna E.; Yu, Wayne; Sood, Akshay; Yang, Jie; Parmigiani, Giovanni; Matsui, William; Berman, David M.

2011-01-01

Highly tumorigenic cancer cell (HTC) populations have been identified for a variety of solid tumors and assigned stem cell properties. Strategies for identifying HTCs in solid tumors have been primarily empirical rather than rational, particularly in epithelial tumors, which are responsible for 80% of cancer deaths. We report evidence for a spatially restricted bladder epithelial (urothelial) differentiation program in primary urothelial cancers (UCs) and in UC xenografts. We identified a highly tumorigenic UC cell compartment that resembles benign urothelial stem cells (basal cells), co-expresses the 67-kDa laminin receptor and the basal cell-specific cytokeratin CK17, and lacks the carcinoembryonic antigen family member CEACAM6 (CD66c). This multipotent compartment resides at the tumor-stroma interface, is easily identified on histologic sections, and possesses most, if not all, of the engraftable tumor-forming ability in the parental xenograft. We analyzed differential expression of genes and pathways in basal-like cells versus more differentiated cells. Among these, we found significant enrichment of pathways comprising “hallmarks” of cancer, and pharmacologically targetable signaling pathways, including Janus kinase-signal transducer and activator of transcription, Notch, focal adhesion, mammalian target of rapamycin, epidermal growth factor receptor (erythroblastic leukemia viral oncogene homolog [ErbB]), and wingless-type MMTV integration site family (Wnt). The basal/HTC gene expression signature was essentially invisible within the context of nontumorigenic cell gene expression and overlapped significantly with genes driving progression and death in primary human UC. The spatially restricted epithelial differentiation program described here represents a conceptual advance in understanding cellular heterogeneity of carcinomas and identifies basal-like HTCs as attractive targets for cancer therapy. PMID:19544456

[Comparison of the results of long term oxygen therapy in patients treated sequentially using stationary or a portable source of oxygen].

PubMed

Czajkowska-Malinowska, Małgorzata; Połtyn, Beata; Ciesielska, Anna; Kruża, Katarzyna; Jesionka, Paweł

2012-01-01

In long term oxygen therapy (LTOT) two oxygen sources are used, i.e. the stationary oxygen concentrator (OC) and portable liquid oxygen (LO). Polish NHS reimburses stationary oxygen sources only. The aim of this study was to compare the effect of change from OC into LO in patients treated using LTOT. The study involved 30 patients qualified to LTOT. The degree of dyspnoea intensity, (MRC, Borg scale), exercise tolerance (6MWT), fitness, daily use of oxygen therapy, red blood count, lung function, number of exacerbations as well as health related quality of life (SGRQ) were assessed before introduction of LTOT, after 6 months of oxygen therapy using OC and after 6 months from change into LO. During first 6 months RBC decreased from 5.4 to 5.1 (p < 0.0001), HTC from 50.1% to 47.8% (p < 0.0001), 6MWD increased from 337.7 to 378.7 m (p < 0.0001), SGRQ score improved from 72.1 points to 64.4 points (p < 0.0001). Treatment with LO resulted in further improvement in studied parameters: RBC decreased from 5.1 to 4.8 (p < 0.0001), HTC from 47.8% to 44.3% (p < 0.0001), 6MWD increased from 378.7 m to 413 m (p < 0.0001), SGRQ score improved from 64.4 points to 54.9 points (p < 0.0001). Significant increase in daily oxygen breathing hours from 13.7 to 18.9 (p < 0.0001) was also observed. Use of liquid oxygen enables oxygen therapy at home and during ambulation and increases oxygen breathing hours, thus improving red blood count, exercise capacity and health related quality of life.

Improvements of high-throughput culturing yielded novel SAR11 strains and other abundant marine bacteria from the Oregon coast and the Bermuda Atlantic Time Series study site.

PubMed

Stingl, Ulrich; Tripp, Harry James; Giovannoni, Stephen J

2007-08-01

The introduction of high-throughput dilution-to-extinction culturing (HTC) of marine bacterioplankton using sterilized natural sea water as media yielded isolates of many abundant but previously uncultured marine bacterial clades. In early experiments, bacteria from the SAR11 cluster (class Alphaproteobacteria), which are presumed to be the most abundant prokaryotes on earth, were cultured. Although many additional attempts were made, no further strains of the SAR11 clade were obtained. Here, we describe improvements to the HTC technique, which led to the isolation of 17 new SAR11 strains from the Oregon coast and the Sargasso Sea, accounting for 28% and 31% of all isolates in these experiments. Phylogenetic analysis of the internal transcribed spacer (ITS) region showed that the isolates from the Oregon coast represent three different subclusters of SAR11, while isolates from the Sargasso Sea were more uniform and represented a single ITS cluster. A PCR assay proved the presence of proteorhodopsin (PR) in nearly all SAR11 isolates. Analysis of PR amino-acid sequences indicated that isolates from the Oregon coast were tuned to either green or blue light, while PRs from strains obtained from the Sargasso Sea were exclusively tuned to maximum absorbance in the blue. Interestingly, phylogenies based on PR and ITS did not correlate, suggesting lateral gene transfer. In addition to the new SAR11 strains, many novel strains belonging to clusters of previously uncultured or undescribed species of different bacterial phyla, including the first strain of the highly abundant alphaproteobacterial SAR116 clade, were isolated using the modified methods.

Towards Defining the Ecological Niches of Novel Coastal Gulf of Mexico Bacterial Isolates

NASA Astrophysics Data System (ADS)

Henson, M. W.; Thrash, C.; Nall, E.

2016-02-01

The study of microbial contributions to biogeochemistry is critical to understanding the cycles of fundamental compounds and gain predictive capabilities in a changing environment. Such study requires observation of microbial communities and genetics in nature, coupled with experimental testing of hypotheses both in situ and in laboratory settings. This study combines dilution-to-extinction based high-throughput culturing (HTC) with cultivation-independent and geochemical measurements to define potential ecological niches of novel bacterial isolates from the coastal northern Gulf of Mexico (cnGOM). Here we report findings from the first of a three-year project. In total, 43 cultures from seven HTC experiments were capable of being repeatedly transferred. Sanger sequencing of the 16S rRNA gene identified these isolates as belonging to the phyla Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, and Betaproteobacteria. Eight are being genome sequenced, with two selected for further physiological characterization due to their phylogenic novelty and potential ecological significance. Strain LSUCC101 likely represents a novel family of Gammaproteobacteria (best blast hit to a cultured representative showed 91% sequence identity) and strain LSUCC96 belongs to the OM252 clade, with the Hawaiian isolate HIMB30 as its closest relative. Both are small (0.3-0.5 µm) cocci. The environmental importance of both LSUCC101 and LSUCC96 was illustrated by their presence within the top 30 OTU0.03 of cnGOM 16S rRNA gene datasets as well as within clone libraries from coastal regions around the world. Ongoing work is determining growth efficiencies, substrate utilization profiles, and metabolic potential to elucidate the roles of these organisms in the cnGOM. Comparative genomics will examine the evolutionary divergence of these organisms from their closest neighbors, and metagenomic recruitment to genomes will help identify strain-based variation from different coastal regions.

[Determination of radioactivity by smartphones].

PubMed

Hartmann, H; Freudenberg, R; Andreeff, M; Kotzerke, J

2013-01-01

The interest in the detection of radioactive materials has strongly increased after the accident in the nuclear power plant Fukushima and has led to a bottleneck of suitable measuring instruments. Smartphones equipped with a commercially available software tool could be used for dose rate measurements following a calibration according to the specific camera module. We examined whether such measurements provide reliable data for typical activities and radionuclides in nuclear medicine. For the nuclides 99mTc (10 - 1000 MBq), 131I (3.7 - 1800 MBq, therapy capsule) and 68Ga (50 - 600 MBq) radioactivity with defined geometry in different distances was measured. The smartphones Milestone Droid 1 (Motorola) and HTC Desire (HTC Corporation) were compared with the standard instruments AD6 (automess) and DoseGUARD (AEA Technology). Measurements with the smartphones and the other devices show a good agreement: linear signal increase with rising activity and dose rate. The long time measurement (131I, 729 MBq, 0.5 m, 60 min) demonstrates a considerably higher variation (by 20%) of the measured smartphone data values compared with the AD6. For low dose rates (< 1 µGy/h), the sensitivity decreases so that measurements of e. g. the natural radiation exposure do not lead to valid results. The calibration of the camera responsivity for the smartphone has a big influence on the results caused by the small detector surface of the camera semiconductor. With commercial software the camera module of a smartphone can be used for the measurement of radioactivity. Dose rates resulting from typical nuclear medicine procedures can be measured reliably (e. g., dismissal dose after radioiodine therapy). The signal shows a high correlation to measured values of conventional dose measurement devices.

Autophagy is induced through the ROS-TP53-DRAM1 pathway in response to mitochondrial protein synthesis inhibition.

PubMed

Xie, Xiaolei; Le, Li; Fan, Yanxin; Lv, Lin; Zhang, Junjie

2012-07-01

Mitoribosome in mammalian cells is responsible for synthesis of 13 mtDNA-encoded proteins, which are integral parts of four mitochondrial respiratory chain complexes (I, III, IV and V). ERAL1 is a nuclear-encoded GTPase important for the formation of the 28S small mitoribosomal subunit. Here, we demonstrate that knockdown of ERAL1 by RNA interference inhibits mitochondrial protein synthesis and promotes reactive oxygen species (ROS) generation, leading to autophagic vacuolization in HeLa cells. Cells that lack ERAL1 expression showed a significant conversion of LC3-I to LC3-II and an enhanced accumulation of autophagic vacuoles carrying the LC3 marker, all of which were blocked by the autophagy inhibitor 3-MA as well as by the ROS scavenger NAC. Inhibition of mitochondrial protein synthesis either by ERAL1 siRNA or chloramphenicol (CAP), a specific inhibitor of mitoribosomes, induced autophagy in HTC-116 TP53 (+/+) cells, but not in HTC-116 TP53 (-/-) cells, indicating that tumor protein 53 (TP53) is essential for the autophagy induction. The ROS elevation resulting from mitochondrial protein synthesis inhibition induced TP53 expression at transcriptional levels by enhancing TP53 promoter activity, and increased TP53 protein stability by suppressing TP53 ubiquitination through MAPK14/p38 MAPK-mediated TP53 phosphorylation. Upregulation of TP53 and its downstream target gene DRAM1, but not CDKN1A/p21, was required for the autophagy induction in ERAL1 siRNA or CAP-treated cells. Altogether, these data indicate that autophagy is induced through the ROS-TP53-DRAM1 pathway in response to mitochondrial protein synthesis inhibition.

Caution on the use of NBS 30 biotite for hydrogen-isotope measurements with on-line high-temperature conversion systems

USGS Publications Warehouse

Qi, Haiping; Coplen, Tyler B.; Olack, Gerard; Vennemann, Torsten W.

2014-01-01

RATIONALEThe supply of NBS 30 biotite is nearly exhausted. During measurements of NBS 30 and potential replacements, reproducible δ2HVSMOW-SLAP values could not be obtained by three laboratories using high-temperature conversion (HTC) systems. The cause of this issue has been investigated using the silver-tube technique for hydrogen-isotope measurements of water.METHODSThe δ2HVSMOW-SLAP values of NBS 30 biotite, other biotites, muscovites, and kaolinite with different particle sizes, along with IAEA-CH-7 polyethylene, and reference waters and NBS 22 oil that were sealed in silver-tube segments, were measured. The effect of absorbed water on mineral surfaces was investigated with waters both enriched and depleted in 2H. The quantitative conversion of hydrogen from biotite into gaseous hydrogen as a function of mass and particle size was also investigated.RESULTSThe δ2HVSMOW-SLAP values of NBS 30 obtained by three laboratories were as much as 21 ‰ too high compared with the accepted value of −65.7 ‰, determined by conventional off-line measurements. The experiments showed a strong correlation between grain size and the δ2HVSMOW-SLAP value of NBS 30 biotite, but not of biotites with lower iron content. The δ2HVSMOW-SLAP values of NBS 30 as a function of particle size show a clear trend toward −65.7 ‰ with finer grain size.CONCLUSIONSDetermination of the δ2HVSMOW-SLAP values of hydrous minerals and of NBS 30 biotite by on-line HTC systems coupled to isotope-ratio mass spectrometers may be unreliable because hydrogen in this biotite may not be converted quantitatively into molecular hydrogen. Extreme caution in the use and interpretation of δ2HVSMOW-SLAP on-line measurements of hydrous minerals is recommended.

Virtual Reality as Innovative Approach to the Interior Designing

NASA Astrophysics Data System (ADS)

Kaleja, Pavol; Kozlovská, Mária

2017-06-01

We can observe significant potential of information and communication technologies (ICT) in interior designing field, by development of software and hardware virtual reality tools. Using ICT tools offer realistic perception of proposal in its initial idea (the study). A group of real-time visualization, supported by hardware tools like Oculus Rift HTC Vive, provides free walkthrough and movement in virtual interior with the possibility of virtual designing. By improving of ICT software tools for designing in virtual reality we can achieve still more realistic virtual environment. The contribution presented proposal of an innovative approach of interior designing in virtual reality, using the latest software and hardware ICT virtual reality technologies

Improving energy efficiency in handheld biometric applications

NASA Astrophysics Data System (ADS)

Hoyle, David C.; Gale, John W.; Schultz, Robert C.; Rakvic, Ryan N.; Ives, Robert W.

2012-06-01

With improved smartphone and tablet technology, it is becoming increasingly feasible to implement powerful biometric recognition algorithms on portable devices. Typical iris recognition algorithms, such as Ridge Energy Direction (RED), utilize two-dimensional convolution in their implementation. This paper explores the energy consumption implications of 12 different methods of implementing two-dimensional convolution on a portable device. Typically, convolution is implemented using floating point operations. If a given algorithm implemented integer convolution vice floating point convolution, it could drastically reduce the energy consumed by the processor. The 12 methods compared include 4 major categories: Integer C, Integer Java, Floating Point C, and Floating Point Java. Each major category is further divided into 3 implementations: variable size looped convolution, static size looped convolution, and unrolled looped convolution. All testing was performed using the HTC Thunderbolt with energy measured directly using a Tektronix TDS5104B Digital Phosphor oscilloscope. Results indicate that energy savings as high as 75% are possible by using Integer C versus Floating Point C. Considering the relative proportion of processing time that convolution is responsible for in a typical algorithm, the savings in energy would likely result in significantly greater time between battery charges.

Ecopsychosocial Aspects of Human–Tiger Conflict: An Ethnographic Study of Tiger Widows of Sundarban Delta, India

PubMed Central

Chowdhury, Arabinda N.; Mondal, Ranajit; Brahma, Arabinda; Biswas, Mrinal K.

2016-01-01

AIMS Human–tiger conflict (HTC) is a serious public health issue in Sundarban Reserve Forest, India. HTC is a continued concern for the significant mortality and morbidity of both human and tiger population. This is the first comprehensive report on Sundarban tiger–human conflicts and its impact on widows whose husbands were killed by tigers. The study attempts to explore the situation analysis of HTC and the aftermath of the incident including bereavement and coping, the cultural stigma related to being killed by a tiger and the consequent discrimination, deprivation, and social rejection, and the impact on the mental health of the tiger-widows. METHODS This is a three-phase ethnographic research with a mix of quantitative and qualitative methods. In the first phase, a door-to-door village survey (3,084 households) was carried out in two villages of Sundarban, which are adjacent to the Reserve Forest, in which the incidents of human–animal conflicts and the 65 tiger-widows identified were documented. In the second phase, the 65 tiger-widows were studied to explore the ecodemography of tiger attacks and tiger-widows alongside the stigma issue by using a stigma questionnaire (n = 49). The stigma burden was compared with normal widows (n = 21) and snake-bite widows (n = 18). In the third phase, the psychosocial and cultural dimensions related to tiger attacks were studied by using in-depth interviews (IDI) of the tiger-widows, focus-group discussions (FGD), and participatory mapping in the community. Clinical examinations of the mental health of the widows were also carried out in this phase. RESULTS The mean age of the 65 widows was 43.49 ± 9.58 years. Of this, 12.3% of the widows had remarried and only 4.6% of the widows were literate. In all, 67.2% of all tiger attacks occurred as a result of illegal forest entry. The main livelihood of the former husbands of the widows were 43.8% wood cutting, 28.1% fishing, 10.9% crab catching, 9.4% tiger prawn seed (juvenile prawn), and 4.7% honey collection. The maximum number of attacks took place in the months of December (24.6%) and November (13.9%). The majority of incidences happened during the morning hours (47.7%) of the day. Of the cases, 86.1% were attacked while the person was engaged in livelihood activity. In all, 57.4% widows are recorded as living “below the poverty line”. Currently, 45.5% widows earn their living by laboring work followed by forest-based livelihood activities (30%) and begging (5.2%). Tiger-widows differed significantly (P < 0.001) from both normal and snake-bite widows on all stigma cluster scores and the total score. Of the tiger-widows, 44% were shown to be suffering from some designated mental illness. IDIs and FGDs helped to unfold the cultural construct of stigma related to tiger-killing. This can be seen in how the tiger-widows’ quality of life has been negatively impacted in the way their economic and social security, health, remarriage opportunities, and child upbringing is restricted, along with a multitude of posttrauma psychological scars, deprivation, abuse, and exploitation. CONCLUSIONS The study highlights the multitude of sufferings experienced by the tiger-widows including the issues of the gender aspect of HTC and the ecopsychiatric risk factors of tiger attacks combined with the background of local sociocultural beliefs and practices. It is well known that a similar problem also exists in Bangladesh Sundarban as well, in which case it may be that a strong and practical administrative strategy for sustainable alternative income generation and a balanced conservation policy with integrated participatory forest management may go to save both human and tiger. A community ecocultural mental health program involving all the stakeholders (community, gram panchayat, and forest department) and aiming to address and even eradicate the cultural stigma of tiger attack may help to reduce the stigma burden and socicultural discrimination currently experienced by the tiger-widows. PMID:26792997

Ecopsychosocial Aspects of Human-Tiger Conflict: An Ethnographic Study of Tiger Widows of Sundarban Delta, India.

PubMed

Chowdhury, Arabinda N; Mondal, Ranajit; Brahma, Arabinda; Biswas, Mrinal K

2016-01-01

Human-tiger conflict (HTC) is a serious public health issue in Sundarban Reserve Forest, India. HTC is a continued concern for the significant mortality and morbidity of both human and tiger population. This is the first comprehensive report on Sundarban tiger-human conflicts and its impact on widows whose husbands were killed by tigers. The study attempts to explore the situation analysis of HTC and the aftermath of the incident including bereavement and coping, the cultural stigma related to being killed by a tiger and the consequent discrimination, deprivation, and social rejection, and the impact on the mental health of the tiger-widows. This is a three-phase ethnographic research with a mix of quantitative and qualitative methods. In the first phase, a door-to-door village survey (3,084 households) was carried out in two villages of Sundarban, which are adjacent to the Reserve Forest, in which the incidents of human-animal conflicts and the 65 tiger-widows identified were documented. In the second phase, the 65 tiger-widows were studied to explore the ecodemography of tiger attacks and tiger-widows alongside the stigma issue by using a stigma questionnaire (n = 49). The stigma burden was compared with normal widows (n = 21) and snake-bite widows (n = 18). In the third phase, the psychosocial and cultural dimensions related to tiger attacks were studied by using in-depth interviews (IDI) of the tiger-widows, focus-group discussions (FGD), and participatory mapping in the community. Clinical examinations of the mental health of the widows were also carried out in this phase. The mean age of the 65 widows was 43.49 ± 9.58 years. Of this, 12.3% of the widows had remarried and only 4.6% of the widows were literate. In all, 67.2% of all tiger attacks occurred as a result of illegal forest entry. The main livelihood of the former husbands of the widows were 43.8% wood cutting, 28.1% fishing, 10.9% crab catching, 9.4% tiger prawn seed (juvenile prawn), and 4.7% honey collection. The maximum number of attacks took place in the months of December (24.6%) and November (13.9%). The majority of incidences happened during the morning hours (47.7%) of the day. Of the cases, 86.1% were attacked while the person was engaged in livelihood activity. In all, 57.4% widows are recorded as living "below the poverty line". Currently, 45.5% widows earn their living by laboring work followed by forest-based livelihood activities (30%) and begging (5.2%). Tiger-widows differed significantly (P < 0.001) from both normal and snake-bite widows on all stigma cluster scores and the total score. Of the tiger-widows, 44% were shown to be suffering from some designated mental illness. IDIs and FGDs helped to unfold the cultural construct of stigma related to tiger-killing. This can be seen in how the tiger-widows' quality of life has been negatively impacted in the way their economic and social security, health, remarriage opportunities, and child upbringing is restricted, along with a multitude of posttrauma psychological scars, deprivation, abuse, and exploitation. The study highlights the multitude of sufferings experienced by the tiger-widows including the issues of the gender aspect of HTC and the ecopsychiatric risk factors of tiger attacks combined with the background of local sociocultural beliefs and practices. It is well known that a similar problem also exists in Bangladesh Sundarban as well, in which case it may be that a strong and practical administrative strategy for sustainable alternative income generation and a balanced conservation policy with integrated participatory forest management may go to save both human and tiger. A community ecocultural mental health program involving all the stakeholders (community, gram panchayat, and forest department) and aiming to address and even eradicate the cultural stigma of tiger attack may help to reduce the stigma burden and socicultural discrimination currently experienced by the tiger-widows.

In vitro protective effects of botryosphaeran, a (1→3;1→6)-β-d-glucan, against mutagens in normal and tumor rodent cells.

PubMed

Kerche-Silva, Leandra E; Cólus, Ilce M S; Malini, Maressa; Mori, Mateus Prates; Dekker, Robert F H; Barbosa-Dekker, Aneli M

2017-02-01

Botryosphaeran (BOT) is an exocellular β-d-glucan (carbohydrate biopolymer) of the (1→3;1→6)-linked type produced by Botryosphaeria rhodina MAMB-05. The cytotoxic, mutagenic, genotoxic, and protective effects of this substance were evaluated in Chinese hamster lung fibroblasts (V79) and rat hepatocarcinoma cells (HTC) by the micronucleus test (MN) and the comet assay. BOT was not genotoxic in either cell line; it decreased the clastogenic effects of doxorubicin, H 2 O 2 , and benzo[a]pyrene. These results indicate that BOT may have potential as a therapeutic agent. Copyright © 2016 Elsevier B.V. All rights reserved.

40 CFR 458.40 - Applicability; description of the carbon black lamp process subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... carbon black lamp process subcategory. 458.40 Section 458.40 Protection of Environment ENVIRONMENTAL... CATEGORY Carbon Black Lamp Process Subcategory § 458.40 Applicability; description of the carbon black lamp... production of carbon black by the lamp process. ...

Method of manufacturing carbon nanotubes

NASA Technical Reports Server (NTRS)

Benavides, Jeanette M. (Inventor); Leidecker, Henning W. (Inventor); Frazier, Jeffrey (Inventor)

2004-01-01

A process for manufacturing carbon nanotubes, including a step of inducing electrical current through a carbon anode and a carbon cathode under conditions effective to produce the carbon nanotubes, wherein the carbon cathode is larger than the carbon anode. Preferably, a welder is used to induce the electrical current via an arc welding process. Preferably, an exhaust hood is placed on the anode, and the process does not require a closed or pressurized chamber. The process provides high-quality, single-walled carbon nanotubes, while eliminating the need for a metal catalyst.

Physico-Chemical Properties of MgGa Mixed Oxides and Reconstructed Layered Double Hydroxides and Their Performance in Aldol Condensation of Furfural and Acetone

PubMed Central

Kikhtyanin, Oleg; Čapek, Libor; Tišler, Zdeněk; Velvarská, Romana; Panasewicz, Adriana; Diblíková, Petra; Kubička, David

2018-01-01

MgGa layered double hydroxides (Mg/Ga = 2–4) were synthesized and used for the preparation of MgGa mixed oxides and reconstructed hydrotalcites. The properties of the prepared materials were examined by physico-chemical methods (XRD, TGA, NH3-TPD, CO2-TPD, SEM, and DRIFT) and tested in aldol condensation of furfural and acetone. The as-prepared phase-pure MgGa samples possessed hydrotalcite structure, and their calcination resulted in mixed oxides with MgO structure with a small admixture phase characterized by a reflection at 2θ ≈ 36.0°. The interaction of MgGa mixed oxides with pure water resulted in reconstruction of the HTC structure already after 15 s of the rehydration with maximum crystallinity achieved after 60 s. TGA-MS experiments proved a substantial decrease in carbonates in all rehydrated samples compared with their as-prepared counterparts. This allowed suggesting presence of interlayer hydroxyls in the samples. Acido-basic properties of MgGa mixed oxides determined by TPD technique did not correlate with Mg/Ga ratio which was explained by the specific distribution of Ga atoms on the external surface of the samples. CO2-TPD method was also used to evaluate the basic properties of the reconstructed MgGa samples. In these experiments, an intensive peak at T = 450°C on CO2-TPD curve was attributed to the decomposition of carbonates newly formed by CO2 interaction with interlayer carbonates rather than to CO2 desorption from basic sites. Accordingly, CO2-TPD method quantitatively characterized the interlayer hydroxyls only indirectly. Furfural conversion on reconstructed MgGa materials was much larger compared with MgGa mixed oxides confirming that Brønsted basic sites in MgGa catalysts, like MgAl catalysts, were active in the reaction. Mg/Ga ratio in mixed oxides influenced product selectivity which was explained by the difference in textural properties of the samples. In contrast, Mg/Ga ratio in reconstructed catalysts had practically no effect on the composition of reaction products suggesting that the basic sites in these catalysts acted similarly in aldol condensation of acetone with furfural. It was concluded that the properties of MgGa samples resembled in a great extent those of MgAl hydrotalcite-based materials and demonstrated their potential as catalysts for base-catalyzed reactions. PMID:29881721

Physico-Chemical Properties of MgGa Mixed Oxides and Reconstructed Layered Double Hydroxides and Their Performance in Aldol Condensation of Furfural and Acetone.

PubMed

Kikhtyanin, Oleg; Čapek, Libor; Tišler, Zdeněk; Velvarská, Romana; Panasewicz, Adriana; Diblíková, Petra; Kubička, David

2018-01-01

MgGa layered double hydroxides (Mg/Ga = 2-4) were synthesized and used for the preparation of MgGa mixed oxides and reconstructed hydrotalcites. The properties of the prepared materials were examined by physico-chemical methods (XRD, TGA, NH 3 -TPD, CO 2 -TPD, SEM, and DRIFT) and tested in aldol condensation of furfural and acetone. The as-prepared phase-pure MgGa samples possessed hydrotalcite structure, and their calcination resulted in mixed oxides with MgO structure with a small admixture phase characterized by a reflection at 2θ ≈ 36.0°. The interaction of MgGa mixed oxides with pure water resulted in reconstruction of the HTC structure already after 15 s of the rehydration with maximum crystallinity achieved after 60 s. TGA-MS experiments proved a substantial decrease in carbonates in all rehydrated samples compared with their as-prepared counterparts. This allowed suggesting presence of interlayer hydroxyls in the samples. Acido-basic properties of MgGa mixed oxides determined by TPD technique did not correlate with Mg/Ga ratio which was explained by the specific distribution of Ga atoms on the external surface of the samples. CO 2 -TPD method was also used to evaluate the basic properties of the reconstructed MgGa samples. In these experiments, an intensive peak at T = 450°C on CO 2 -TPD curve was attributed to the decomposition of carbonates newly formed by CO 2 interaction with interlayer carbonates rather than to CO 2 desorption from basic sites. Accordingly, CO 2 -TPD method quantitatively characterized the interlayer hydroxyls only indirectly. Furfural conversion on reconstructed MgGa materials was much larger compared with MgGa mixed oxides confirming that Brønsted basic sites in MgGa catalysts, like MgAl catalysts, were active in the reaction. Mg/Ga ratio in mixed oxides influenced product selectivity which was explained by the difference in textural properties of the samples. In contrast, Mg/Ga ratio in reconstructed catalysts had practically no effect on the composition of reaction products suggesting that the basic sites in these catalysts acted similarly in aldol condensation of acetone with furfural. It was concluded that the properties of MgGa samples resembled in a great extent those of MgAl hydrotalcite-based materials and demonstrated their potential as catalysts for base-catalyzed reactions.

Physico-chemical properties of MgGa mixed oxides and reconstructed layered double hydroxides and their performance in aldol condensation of furfural and acetone

NASA Astrophysics Data System (ADS)

Kikhtyanin, Oleg; Čapek, Libor; Tišler, Zdeněk; Velvarská, Romana; Panasewicz, Adriana; Diblíková, Petra; Kubička, David

2018-05-01

MgGa layered double hydroxides (Mg/Ga=2-4) were synthesized and used for the preparation of MgGa mixed oxides and reconstructed hydrotalcites. The properties of the prepared materials were examined by physico-chemical methods (XRD, TGA, NH3-TPD, CO2-TPD, SEM and DRIFT) and tested in aldol condensation of furfural and acetone. The as-prepared phase-pure MgGa samples possessed hydrotalcite structure, and their calcination resulted in mixed oxides with MgO structure with a small admixture phase characterized by a reflection at 2θ ≈ 36.0°. The interaction of MgGa mixed oxides with pure water resulted in reconstruction of the HTC structure already after 15 s of the rehydration with maximum crystallinity achieved after 60 s. TGA-MS experiments proved a substantial decrease in carbonates in all rehydrated samples compared with their as-prepared counterparts. This allowed suggesting presence of interlayer hydroxyls in the samples. Acido-basic properties of MgGa mixed oxides determined by TPD technique did not correlate with Mg/Ga ratio which was explained by the specific distribution of Ga atoms on the external surface of the samples. CO2-TPD method was also used to evaluate the basic properties of the reconstructed MgGa samples. In these experiments, an intensive peak at T=450 °C on CO2-TPD curve was attributed to the decomposition of carbonates newly formed by CO2 interaction with interlayer carbonates rather than to CO2 desorption from basic sites. Accordingly, CO2-TPD method quantitatively characterized the interlayer hydroxyls only indirectly. Furfural conversion on reconstructed MgGa materials was much larger compared with MgGa mixed oxides confirming that Brønsted basic sites in MgGa catalysts, like MgAl catalysts, were active in the reaction. Mg/Ga ratio in mixed oxides influenced product selectivity which was explained by the difference in textural properties of the samples. In contrast, Mg/Ga ratio in reconstructed catalysts had practically no effect on the composition of reaction products suggesting that the basic sites in these catalysts acted similarly in aldol condensation of acetone with furfural. It was concluded that the properties of MgGa samples resembled in a great extent those of MgAl hydrotalcite-based materials and demonstrated their potential as catalysts for base-catalyzed reactions.

Outcomes and Impact of HIV Prevention, ART and TB Programs in Swaziland – Early Evidence from Public Health Triangulation

PubMed Central

van Schalkwyk, Cari; Mndzebele, Sibongile; Hlophe, Thabo; Garcia Calleja, Jesus Maria; Korenromp, Eline L.; Stoneburner, Rand; Pervilhac, Cyril

2013-01-01

Introduction Swaziland’s severe HIV epidemic inspired an early national response since the late 1980s, and regular reporting of program outcomes since the onset of a national antiretroviral treatment (ART) program in 2004. We assessed effectiveness outcomes and mortality trends in relation to ART, HIV testing and counseling (HTC), tuberculosis (TB) and prevention of mother to child transmission (PMTCT). Methods Data triangulated include intervention coverage and outcomes according to program registries (2001-2010), hospital admissions and deaths disaggregated by age and sex (2001-2010) and population mortality estimates from the 1997 and 2007 censuses and the 2007 demographic and health survey. Results By 2010, ART reached 70% of the estimated number of people living with HIV/AIDS with CD4<350/mm3, with progressively improving patient retention and survival. As of 2010, 88% of health facilities providing antenatal care offered comprehensive PMTCT services. The HTC program recorded a halving in the proportion of adults tested who were HIV-infected; similarly HIV infection rates among HIV-exposed babies halved from 2007 to 2010. Case fatality rates among hospital patients diagnosed with HIV/AIDS started to decrease from 2005–6 in adults and especially in children, contrasting with stable case fatality for other causes including TB. All-cause child in-patient case fatality rates started to decrease from 2005–6. TB case notifications as well as rates of HIV/TB co-infection among notified TB patients continued a steady increase through 2010, while coverage of HIV testing and CPT for co-infected patients increased to above 80%. Conclusion Against a background of high, but stable HIV prevalence and decreasing HIV incidence, we documented early evidence of a mortality decline associated with the expanded national HIV response since 2004. Attribution of impact to specific interventions (versus natural epidemic dynamics) will require additional data from future household surveys, and improved routine (program, surveillance, and hospital) data at district level. PMID:23922711

A qualitative study of the determinants of HIV guidelines implementation in two south-eastern districts of Tanzania

PubMed Central

Geubbels, Eveline; Wringe, Alison; Todd, Jim; Klatser, Paul; Dieleman, Marjolein

2017-01-01

Abstract Current HIV policies in Tanzania have adopted the three long-term impact results of zero new infections, zero HIV deaths and zero stigma and discrimination. Strategies to reach these results include scaling-up HIV Testing and Counselling (HTC); Preventing Mother-To-Child Transmission (PMTCT); and strengthening Care and Treatment Clinic (CTC) services. Previous studies showed that HIV policy and guideline recommendations were not always implemented in rural South Tanzania. This study aims to identify the determinants of HIV guideline implementation. A qualitative study of 23 semi-structured interviews with facility in-charges; healthcare workers; district, regional and national HIV coordinators was conducted. Five health facilities were purposively selected by level, ownership and proximity to district headquarters. Interviews were analysed according to Fleuren’s five determinants of innovation uptake related to: strategies used in guideline development and dissemination; guideline characteristics; the guideline implementing organization; guideline users; and the socio-cultural and regulatory context. None of the facilities had the HTC national guideline document. Non-involvement of providers in revisions and weak planning for guideline dissemination impeded their implementation. Lengthy guidelines and those written in English were under-used, and activities perceived to be complicated, like WHO-staging, were avoided. Availability of staff and lack of supplies like test kits and medication impeded implementation. Collaboration between facilities enhanced implementation, as did peer-support among providers. Provider characteristics including education level, knowledge of, and commitment to the guideline influenced implementation. According to providers, determinants of clients’ service use included gender norms, stigma, trust and perceived benefits. The regulatory context prohibited private hospitals from buying HIV supplies. Being tools for bringing policies to practice, national guidelines are crucial in the efforts towards the three zeros. Strategies to improve providers’ adherence to guidelines should include development of clearer guideline dissemination plans, strengthening of the health system, and possibly addressing of provider-perceived patient-level barriers to utilizing HIV services. PMID:28369374

Maximizing HIV partner notification opportunities for index patients and their sexual partners in Malawi.

PubMed

Kamanga, G; Brown, L; Jawati, P; Chiwanda, D; Nyirenda, N

2015-12-01

HIV testing and counselling (HTC) is important to effect positive sexual behaviour change and is an entry point to treatment, care, and psychosocial support. One of the most practical initiatives to increase HTC is to encourage sexual partners of HIV-infected persons to test for HIV. However, partner notification strategies must be feasible in the healthcare setting and acceptable to the population. We conducted a qualitative study during the pilot phase of an HIV partner notification trial to complement its assessment of feasibility and acceptability of methods of partner notification. We performed in-depth interviews with 16 consecutive HIV-positive index participants who consented and their 12 identifiable sexual partners. We also conducted two focus group discussions with healthcare workers to supplement the patient perspectives. In the main study, newly diagnosed HIV cases (index cases) were randomized to one of three methods of partner notification: passive, contract, and provider referral. Clients in the passive referral group were responsible for notifying their sexual partners themselves. Individuals in the contract referral group were given seven days to notify their partners, after which a healthcare provider contacted partners who had not reported for counselling and testing. In the provider group, a healthcare provider notified partners directly. Although most index participants and partners expressed a preference for passive notification, they also highlighted benefits for provider-assisted notification and the universal right for all HIV-exposed persons to know their HIV exposure and benefit from HIV testing and access antiretroviral treatment. Several participants mentioned couples counselling as a way to diffuse tension and get accurate information. All mentioned benefits to HIV testing, including the opportunity to change behaviour. Provider-assisted partner notification is not preferred, but it is acceptable and may complement the passive method of notification. Couples counselling should also be encouraged.

A genetic risk score is associated with hepatic triglyceride content and non-alcoholic steatohepatitis in Mexicans with morbid obesity.

PubMed

León-Mimila, Paola; Vega-Badillo, Joel; Gutiérrez-Vidal, Roxana; Villamil-Ramírez, Hugo; Villareal-Molina, Teresa; Larrieta-Carrasco, Elena; López-Contreras, Blanca E; Kauffer, Luis R Macías; Maldonado-Pintado, Diana G; Méndez-Sánchez, Nahúm; Tovar, Armando R; Hernández-Pando, Rogelio; Velázquez-Cruz, Rafael; Campos-Pérez, Francisco; Aguilar-Salinas, Carlos A; Canizales-Quinteros, Samuel

2015-04-01

Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) near/in PNPLA3, NCAN, LYPLAL1, PPP1R3B, and GCKR genes associated with non-alcoholic fatty liver disease (NAFLD) mainly in individuals of European ancestry. The aim of the study was to test whether these genetic variants and a genetic risk score (GRS) are associated with elevated liver fat content and non-alcoholic steatohepatitis (NASH) in Mexicans with morbid obesity. 130 morbidly obese Mexican individuals were genotyped for six SNPs in/near PNPLA3, NCAN, LYPLAL1, PPP1R3B, and GCKR genes. Hepatic fat content [triglyceride (HTG) and total cholesterol (HTC)] was quantified directly in liver biopsies and NASH was diagnosed by histology. A GRS was tested for association with liver fat content and NASH using logistic regression models. In addition, 95 ancestry-informative markers were genotyped to estimate population admixture proportions. After adjusting for age, sex and admixture, PNPLA3, LYPLAL1, GCKR and PPP1R3B polymorphisms were associated with higher HTG content (P < 0.05 for PNPLA3, LYPLAL1, GCKR polymorphisms and P = 0.086 for PPP1R3B). The GRS was significantly associated with higher HTG and HTC content (P = 1.0 × 10(-4) and 0.048, respectively), steatosis stage (P = 0.029), and higher ALT levels (P = 0.002). Subjects with GRS ≥ 6 showed a significantly increased risk of NASH (OR = 2.55, P = 0.045) compared to those with GRS ≤ 5. However, the GRS did not predict NASH status, as AUC of ROC curves was 0.56 (P = 0.219). NAFLD associated loci in Europeans and a GRS based on these loci contribute to the accumulation of hepatic lipids and NASH in morbidly obese Mexican individuals. Copyright © 2015 Elsevier Inc. All rights reserved.

HIV Testing and Counseling Leads to Immediate Consistent Condom Use among South African Stable HIV-discordant Couples

PubMed Central

Rosenberg, Nora E; Pettifor, Audrey E; Bruyn, Guy DE; Westreich, Daniel; Delany-Moretlwe, Sinead; Behets, Frieda; Maman, Suzanne; Coetzee, David; Kamupira, Mercy; Miller, William C

2012-01-01

Introduction Effective behavioral HIV prevention is needed for stable HIV-discordant couples at risk for HIV, especially those without access to biomedical prevention. This analysis addressed whether HIV testing and counseling (HTC) with ongoing counseling and condom distribution lead to reduced unprotected sex in HIV-discordant couples. Methods Partners in Prevention HSV/HIV Transmission Study was a randomized trial conducted from 2004–2008 assessing whether acyclovir reduced HIV transmission from HSV-2/HIV-1 co-infected persons to HIV-uninfected sex partners. This analysis relied on self-reported behavioral data from 508 HIV-infected South African participants. The exposure was timing of first HTC: 0–7, 8–14, 15–30, or >30 days before baseline. In each exposure group, predicted probabilities of unprotected sex in the last month were calculated at baseline, month one, and month twelve using generalized estimating equations with a logit link and exchangeable correlation matrix. Results At baseline, participants who knew their HIV status for less time experienced higher predicted probabilities of unprotected sex in the last month: 0–7 days, 0.71; 8–14 days, 0.52; 15–30 days, 0.49; >30 days, 0.26. At month one, once all participants had been aware of being in HIV-discordant relationships for ≥ 1 month, predicted probabilities declined: 0–7 days, 0.08; 8–14 days, 0.08; 15–30 days, 0.15; >30 days, 0.14. Lower predicted probabilities were sustained through month twelve: 0–7 days, 0.08; 8–14 days, 0.11; 15–30 days, 0.05; >30 days, 0.19. Conclusions Unprotected sex declined after HIV-positive diagnosis, and declined further after awareness of HIV-discordance. Identifying HIV-discordant couples for behavioral prevention is important for reducing HIV transmission risk. PMID:23117500

Providing a conceptual framework for HIV prevention cascades and assessing feasibility of empirical measurement with data from east Zimbabwe: a case study.

PubMed

Garnett, Geoffrey P; Hallett, Timothy B; Takaruza, Albert; Hargreaves, James; Rhead, Rebecca; Warren, Mitchel; Nyamukapa, Constance; Gregson, Simon

2016-07-01

The HIV treatment cascade illustrates the steps required for successful treatment and is a powerful advocacy and monitoring tool. Similar cascades for people susceptible to infection could improve HIV prevention programming. We aim to show the feasibility of using cascade models to monitor prevention programmes. Conceptual prevention cascades are described taking intervention-centric and client-centric perspectives to look at supply, demand, and efficacy of interventions. Data from two rounds of a population-based study in east Zimbabwe are used to derive the values of steps for cascades for voluntary medical male circumcision (VMMC) and for partner reduction or condom use driven by HIV testing and counselling (HTC). In 2009 to 2011 the availability of circumcision services was negligible, but by 2012 to 2013 about a third of the population had access. However, where it was available only 12% of eligible men sought to be circumcised leading to an increase in circumcision prevalence from 3·1% to 6·9%. Of uninfected men, 85·3% did not perceive themselves to be at risk of acquiring HIV. The proportions of men and women tested for HIV increased from 27·5% to 56·6% and from 61·1% to 79·6%, respectively, with 30·4% of men tested self-reporting reduced sexual partner numbers and 12·8% reporting increased condom use. Prevention cascades can be populated to inform HIV prevention programmes. In eastern Zimbabwe programmes need to provide greater access to circumcision services and the design and implementation of associated demand creation activities. Whereas, HTC services need to consider how to increase reductions in partner numbers or increased condom use or should not be considered as contributing to prevention services for the HIV-negative adults. Wellcome Trust and Bill & Melinda Gates Foundation. Copyright © 2016 Garnett et al. Open Access article distributed under the terms of CC BY. Published by Elsevier Ltd.. All rights reserved.

Outcomes and impact of HIV prevention, ART and TB programs in Swaziland--early evidence from public health triangulation.

PubMed

van Schalkwyk, Cari; Mndzebele, Sibongile; Hlophe, Thabo; Garcia Calleja, Jesus Maria; Korenromp, Eline L; Stoneburner, Rand; Pervilhac, Cyril

2013-01-01

Swaziland's severe HIV epidemic inspired an early national response since the late 1980s, and regular reporting of program outcomes since the onset of a national antiretroviral treatment (ART) program in 2004. We assessed effectiveness outcomes and mortality trends in relation to ART, HIV testing and counseling (HTC), tuberculosis (TB) and prevention of mother to child transmission (PMTCT). Data triangulated include intervention coverage and outcomes according to program registries (2001-2010), hospital admissions and deaths disaggregated by age and sex (2001-2010) and population mortality estimates from the 1997 and 2007 censuses and the 2007 demographic and health survey. By 2010, ART reached 70% of the estimated number of people living with HIV/AIDS with CD4<350/mm(3), with progressively improving patient retention and survival. As of 2010, 88% of health facilities providing antenatal care offered comprehensive PMTCT services. The HTC program recorded a halving in the proportion of adults tested who were HIV-infected; similarly HIV infection rates among HIV-exposed babies halved from 2007 to 2010. Case fatality rates among hospital patients diagnosed with HIV/AIDS started to decrease from 2005-6 in adults and especially in children, contrasting with stable case fatality for other causes including TB. All-cause child in-patient case fatality rates started to decrease from 2005-6. TB case notifications as well as rates of HIV/TB co-infection among notified TB patients continued a steady increase through 2010, while coverage of HIV testing and CPT for co-infected patients increased to above 80%. Against a background of high, but stable HIV prevalence and decreasing HIV incidence, we documented early evidence of a mortality decline associated with the expanded national HIV response since 2004. Attribution of impact to specific interventions (versus natural epidemic dynamics) will require additional data from future household surveys, and improved routine (program, surveillance, and hospital) data at district level.

Stigma of tiger attack: Study of tiger-widows from Sundarban Delta, India*

PubMed Central

Chowdhury, Arabinda N.; Brahma, Arabinda; Mondal, Ranajit; Biswas, Mrinal K.

2016-01-01

Aims: Human-tiger conflict (HTC) is a serious public health issue in Sundarban Reserve Forest, India. HTC is a continued concern for significant mortality and morbidity of both human and tiger population. This study examined 49 widows, whose husbands were killed by tigers, in order to explore the cultural stigma related with tiger-killing and consequent discrimination and social rejection. Different psychosocial aspects of community stigma associated with tiger-killings is discussed in the context of local culture. Methods: A mix of both quantitative and qualitative methods was used in this ethnographic study in two mouzas of Sundarban adjacent to Reserve Forest, involving (1) Village Survey for Tiger-widows, (2) In-depth interview of the widows, (3) Focus Group discussions, (4) Participatory mapping and (5) Stigma assessment by using a 28 item stigma scale especially devised for this research. For comparison of stigma-burden snake-bite widows and normal widows were taken from the same community. Results: Tiger-widows showed significantly higher stigma scores on all the clusters (fear, negative feelings, disclosure, discrimination, community attitudes, and spiritual dimension) than from both normal and snake-bite widows. They also showed higher total stigma score (65.9 ± 9.8) than normal widows (35.8 ± 8.0) and snake-bite widows (40.1 ± 7.1) and this difference was highly significant (P < 0.001). IDIs and FGDs helped to unfold the cultural construct of stigma related to tiger-killing. This can be seen in how the tiger-widows’ quality of life has been negatively impacted with a multitude of post-trauma psychological scars, deprivation, abuse and exploitation. Conclusions: The study proposes that administrative strategy for sustainable alternative income generation and conservation policy with integrated participatory forest management may save both human and tiger. A community ecocultural mental health programme addressing to eradicate the cultural stigma related with tiger attack, with environmental awareness may help to reduce the social miseries of the tiger-widows. PMID:26985099

Journey to the centre of the cell: Virtual reality immersion into scientific data.

PubMed

Johnston, Angus P R; Rae, James; Ariotti, Nicholas; Bailey, Benjamin; Lilja, Andrew; Webb, Robyn; Ferguson, Charles; Maher, Sheryl; Davis, Thomas P; Webb, Richard I; McGhee, John; Parton, Robert G

2018-02-01

Visualization of scientific data is crucial not only for scientific discovery but also to communicate science and medicine to both experts and a general audience. Until recently, we have been limited to visualizing the three-dimensional (3D) world of biology in 2 dimensions. Renderings of 3D cells are still traditionally displayed using two-dimensional (2D) media, such as on a computer screen or paper. However, the advent of consumer grade virtual reality (VR) headsets such as Oculus Rift and HTC Vive means it is now possible to visualize and interact with scientific data in a 3D virtual world. In addition, new microscopic methods provide an unprecedented opportunity to obtain new 3D data sets. In this perspective article, we highlight how we have used cutting edge imaging techniques to build a 3D virtual model of a cell from serial block-face scanning electron microscope (SBEM) imaging data. This model allows scientists, students and members of the public to explore and interact with a "real" cell. Early testing of this immersive environment indicates a significant improvement in students' understanding of cellular processes and points to a new future of learning and public engagement. In addition, we speculate that VR can become a new tool for researchers studying cellular architecture and processes by populating VR models with molecular data. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Paleomagnetism of a well-dated marine succession in South China: A possible Late Cambrian true polar wander (TPW)

NASA Astrophysics Data System (ADS)

Jiao, Wen-Jun; Li, Yong-Xiang; Yang, Zhen-Yu

2018-04-01

The Cambrian true polar wander (TPW) hypothesis remains controversial largely because of the uncertainties in the quality and/or fidelity of the paleomagnetic data as well as their chronological control. Testing the TPW hypothesis requires high-quality paleomagnetic data of sufficient spatial and temporal resolutions. Here, we present paleomagnetic results of a continuous Cambrian shallow marine succession from South China where available detailed biostratigraphy provides exceptional chronological constraints. Forty-three sites of paleomagnetic samples were collected from this limestone-dominated succession. Stepwise thermal demagnetization generally reveals three-component magnetizations. Low- and intermediate-temperature components can be cleaned by ∼330 °C, and the high-temperature component (HTC) was isolated typically from ∼350 to ∼450 °C. A positive fold test and the presence of reversed polarity in the strata, together with rock magnetic data as well as the scanning electron microscopic (SEM) and transmission electron microscopic (TEM) results, collectively suggest that the HTCs are likely primary. A directional shift of the HTCs occurs between the lower-middle Cambrian and the upper Cambrian strata in the succession and is tentatively interpreted to indicate a ∼57° polar wander from ∼500.5 to 494 Ma. Because the rate of polar wander is too fast to be a tectonic origin, this polar wander is interpreted to represent a Late Cambrian TPW. This TPW appears coeval with the Steptoean positive carbon isotope excursion (SPICE) and the major trilobite mass extinctions, suggesting a potential link between the TPW and the Late Cambrian biotic and climatic changes. Because the proposed TPW event is exceptionally well-dated, it should be testable through examination of other worldwide sections.

Characterization of potassium hydroxide (KOH) modified hydrochars from different feedstocks for enhanced removal of heavy metals from water.

PubMed

Sun, Kejing; Tang, Jingchun; Gong, Yanyan; Zhang, Hairong

2015-11-01

Hydrochars produced from different feedstocks (sawdust, wheat straw, and corn stalk) via hydrothermal carbonization (HTC) and KOH modification were used as alternative adsorbents for aqueous heavy metals remediation. The chemical and physical properties of the hydrochars and KOH-treated hydrochars were characterized, and the ability of hydrochars for removal of heavy metals from aqueous solutions as a function of reaction time, pH, and initial contaminant concentration was tested. The results showed that KOH modification of hydrochars might have increased the aromatic and oxygen-containing functional groups, such as carboxyl groups, resulting in about 2-3 times increase of cadmium sorption capacity (30.40-40.78 mg/g) compared to that of unmodified hydrochars (13.92-14.52 mg/g). The sorption ability among different feedstocks after modification was as the following: sawdust > wheat straw > corn stack. Cadmium sorption kinetics on modified hydrochars could be interpreted with a pseudo-second order, and sorption isotherm was simulated with Langmuir adsorption model. High cadmium uptake on modified hydrochars was observed over the pH range of 4.0-8.0, while for other heavy metals (Pb(2+), Cu(2+), and Zn(2+)) the range was 4.0-6.0. In a multi-metal system, the sorption capacity of heavy metals by modified hydrochars was also higher than that by unmodified ones and followed the order of Pb(II) > Cu(II) > Cd(II) > Zn(II). The results suggest that KOH-modified hydrochars can be used as a low cost, environmental-friendly, and effective adsorbent for heavy metal removal from aqueous solutions.

Production of magnesium metal

DOEpatents

Blencoe, James G [Harriman, TN; Anovitz, Lawrence M [Knoxville, TN; Palmer, Donald A [Oliver Springs, TN; Beard, James S [Martinsville, VA

2010-02-23

A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention further relates to a process for production of magnesium metal or a magnesium compound where an external source of carbon dioxide is not used in any of the reactions of the process. The invention also relates to the magnesium metal produced by the processes described herein.

40 CFR 458.10 - Applicability; description of the carbon black furnace process subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... carbon black furnace process subcategory. 458.10 Section 458.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Furnace Process Subcategory § 458.10 Applicability; description of the carbon black...

40 CFR 458.20 - Applicability: description of the carbon black thermal process subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... carbon black thermal process subcategory. 458.20 Section 458.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Thermal Process Subcategory § 458.20 Applicability: description of the carbon black...

40 CFR 458.30 - Applicability; description of the carbon black channel process subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... carbon black channel process subcategory. 458.30 Section 458.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Channel Process Subcategory § 458.30 Applicability; description of the carbon black...

Hot wire production of single-wall and multi-wall carbon nanotubes

DOEpatents

Dillon, Anne C.; Mahan, Archie H.; Alleman, Jeffrey L.

2010-10-26

Apparatus (210) for producing a multi-wall carbon nanotube (213) may comprise a process chamber (216), a furnace (217) operatively associated with the process chamber (216), and at least one filament (218) positioned within the process chamber (216). At least one power supply (220) operatively associated with the at least one filament (218) heats the at least one filament (218) to a process temperature. A gaseous carbon precursor material (214) operatively associated with the process chamber (216) provides carbon for forming the multi-wall carbon nanotube (213). A metal catalyst material (224) operatively associated with the process (216) catalyzes the formation of the multi-wall carbon nanotube (213).

High surface area carbon and process for its production

DOEpatents

Romanos, Jimmy; Burress, Jacob; Pfeifer, Peter; Rash, Tyler; Shah, Parag; Suppes, Galen

2016-12-13

Activated carbon materials and methods of producing and using activated carbon materials are provided. In particular, biomass-derived activated carbon materials and processes of producing the activated carbon materials with prespecified surface areas and pore size distributions are provided. Activated carbon materials with preselected high specific surface areas, porosities, sub-nm (<1 nm) pore volumes, and supra-nm (1-5 nm) pore volumes may be achieved by controlling the degree of carbon consumption and metallic potassium intercalation into the carbon lattice during the activation process.

Supercritical Carbon Dioxide Regeneration of Activated Carbon Loaded with Contaminants from Rocky Mountain Arsenal Well Water.

DTIC Science & Technology

1982-05-01

PROCESSING COST OF ACTIVATED CHARCOAL REGENERATION BY SUPERCRITICAL CARBON DIOXIDE PROCESS ........................... 25 l IV-4 SENSITIVITY OF GAC...PROCESSING COSTS TO GAC WORKING CAPACITY ................................. 27 IV-5 ESTIMATED PROCESSING COST OF ACTIVATED CHARCOAL REGENERATION BY THERMAL...34 VI-2 COMPARISON OF THREE GRANULAR ACTIVATED CARBONS - SUPERCRITICAL CO2 REACTIVATION - GRANULAR CARBON ISOTHERMS - PHASE I RAW DATA

Handheld Device Adapted to Smartphone Cameras for the Measurement of Sodium Ion Concentrations at Saliva-Relevant Levels via Fluorescence

PubMed Central

Lipowicz, Michelle; Garcia, Antonio

2015-01-01

The use of saliva sampling as a minimally-invasive means for drug testing and monitoring physiology is a subject of great interest to researchers and clinicians. This study describes a new optical method based on non-axially symmetric focusing of light using an oblate spheroid sample chamber. The device is simple, lightweight, low cost and is easily attached to several different brands/models of smartphones (Apple, Samsung, HTC and Nokia) for the measurement of sodium ion levels at physiologically-relevant saliva concentrations. The sample and fluorescent reagent solutions are placed in a specially-designed, lightweight device that excludes ambient light and concentrates 470-nm excitation light, from a low-power photodiode, within the sample through non-axially-symmetric refraction. The study found that smartphone cameras and post-image processing quantitated sodium ion concentration in water over the range of 0.5–10 mM, yielding best-fit regressions of the data that agree well with a data regression of microplate luminometer results. The data suggest that fluorescence can be used for the measurement of salivary sodium ion concentrations in low-resource or point-of-care settings. With further fluorescent assay testing, the device may find application in a variety of enzymatic or chemical assays. PMID:28955016

Vortex pinning landscape in MOD-TFA YBCO nanostroctured films

NASA Astrophysics Data System (ADS)

Gutierrez, J.; Puig, T.; Pomar, A.; Obradors, X.

2008-03-01

A methodology of general validity to study vortex pinning in YBCO based on Jc transport measurements is described. It permits to identify, separate and quantify three basic vortex pinning contributions associated to anisotropic-strong, isotropic-strong and isotropic-weak pinning centers. Thereof, the corresponding vortex pinning phase diagrams are built up. This methodology is applied to the new solution-derived YBCO nanostructured films, including controlled interfacial pinning by the growth of nanostructured templates by means of self-assembled processes [1] and YBCO-BaZrO3 nanocomposites prepared by modified solution precursors. The application of the methodology and comparison with a standard solution-derived YBCO film [2], enables us to identify the nature and the effect of the additional pinning centers induced. The nanostructured templates films show c-axis pinning strongly increased, controlling most of the pinning phase diagram. On the other hand, the nanocomposites have achieved so far, the highest pinning properties in HTc-superconductors [3], being the isotropic-strong defects contribution the origin of their unique properties. [1] M. Gibert et al, Adv. Mat. vol 19, p. 3937 (2007) [2] Puig.T et al, SuST EUCAS 2007 (to be published) [3] J. Gutierrez et al, Nat. Mat. vol. 6, p. 367 (2007) * Work supported by HIPERCHEM, NANOARTIS and MAT2005-02047

Rapid oxidation/stabilization technique for carbon foams, carbon fibers and C/C composites

DOEpatents

Tan, Seng; Tan, Cher-Dip

2004-05-11

An enhanced method for the post processing, i.e. oxidation or stabilization, of carbon materials including, but not limited to, carbon foams, carbon fibers, dense carbon-carbon composites, carbon/ceramic and carbon/metal composites, which method requires relatively very short and more effective such processing steps. The introduction of an "oxygen spill over catalyst" into the carbon precursor by blending with the carbon starting material or exposure of the carbon precursor to such a material supplies required oxygen at the atomic level and permits oxidation/stabilization of carbon materials in a fraction of the time and with a fraction of the energy normally required to accomplish such carbon processing steps. Carbon based foams, solids, composites and fiber products made utilizing this method are also described.

40 CFR 458.40 - Applicability; description of the carbon black lamp process subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... carbon black lamp process subcategory. 458.40 Section 458.40 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Carbon Black Lamp Process Subcategory § 458.40 Applicability; description of the carbon black lamp process subcategory. The provisions of this subpart are applicable to discharges resulting...

40 CFR 458.40 - Applicability; description of the carbon black lamp process subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... carbon black lamp process subcategory. 458.40 Section 458.40 Protection of Environment ENVIRONMENTAL... CATEGORY Carbon Black Lamp Process Subcategory § 458.40 Applicability; description of the carbon black lamp process subcategory. The provisions of this subpart are applicable to discharges resulting from the...

Process for producing metal compounds from graphite oxide

NASA Technical Reports Server (NTRS)

Hung, Ching-Cheh (Inventor)

2000-01-01

A process for providing elemental metals or metal oxides distributed on a carbon substrate or self-supported utilizing graphite oxide as a precursor. The graphite oxide is exposed to one or more metal chlorides to form an intermediary product comprising carbon, metal, chloride, and oxygen This intermediary product can be flier processed by direct exposure to carbonate solutions to form a second intermediary product comprising carbon, metal carbonate, and oxygen. Either intermediary product may be further processed: a) in air to produce metal oxide; b) in an inert environment to produce metal oxide on carbon substrate; c) in a reducing environment to produce elemental metal distributed on carbon substrate. The product generally takes the shape of the carbon precursor.

Process for Producing Metal Compounds from Graphite Oxide

NASA Technical Reports Server (NTRS)

Hung, Ching-Cheh (Inventor)

2000-01-01

A process for providing elemental metals or metal oxides distributed on a carbon substrate or self-supported utilizing graphite oxide as a precursor. The graphite oxide is exposed to one or more metal chlorides to form an intermediary product comprising carbon. metal. chloride. and oxygen This intermediary product can be flier processed by direct exposure to carbonate solutions to form a second intermediary product comprising carbon. metal carbonate. and oxygen. Either intermediary product may be further processed: a) in air to produce metal oxide: b) in an inert environment to produce metal oxide on carbon substrate: c) in a reducing environment. to produce elemental metal distributed on carbon substrate. The product generally takes the shape of the carbon precursor.

Production of magnesium metal

DOEpatents

Blencoe, James G [Harriman, TN; Anovitz, Lawrence M [Knoxville, TN; Palmer, Donald A [Oliver Springs, TN; Beard, James S [Martinsville, VA

2012-04-10

A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention also relates to the magnesium metal produced by the processes described herein.

DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

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

Elliot B. Kennel; Stephen P. Carpenter; Dady Dadyburjor

2006-03-27

The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. These carbon products include materials used in metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, efforts have focused on the development of continuous processes for hydrogenation as well as continuous production of carbon foam and coke.

Elemental Metals or Oxides Distributed on a Carbon Substrate or Self-Supported and the Manufacturing Process Using Graphite Oxide as Template

NASA Technical Reports Server (NTRS)

Hung, Ching-Chen (Inventor)

1999-01-01

A process for providing elemental metals or metal oxides distributed on a carbon substrate or self-supported utilizing graphite oxide as a percursor. The graphite oxide is exposed to one or more metal chlorides to form an intermediary product comprising carbon, metal, chloride, and oxygen. This intermediary product can be further processed by direct exposure to carbonate solutions to form a second intermediary product comprising carbon, metal carbonate, and oxygen. Either intermediary product may be further processed: a) in air to produce metal oxide; b) in an inert environment to produce metal oxide on carbon substrate; c) in a reducing environment to produce elemental metal distributed on carbon substrate. The product generally takes the shape of the carbon precursor.

Elemental Metals or Oxides Distributed on a Carbon Substrate or Self-Supported and the Manufacturing Process Using Graphite Oxide as Template

NASA Technical Reports Server (NTRS)

Hung, Ching-Cheh (Inventor)

1999-01-01

A process for providing elemental metals or metal oxides distributed on a carbon substrate or self-supported utilizing graphite oxide as a precursor. The graphite oxide is exposed to one or more metal chlorides to form an intermediary product comprising carbon, metal, chloride, and oxygen. This intermediary product can be further processed by direct exposure to carbonate-solutions to form a second intermediary product comprising carbon, metal carbonate, and oxygen. Either intermediary product may be further processed: a) in air to produce metal oxide; b) in an inert environment to produce metal oxide on carbon substrate; c) in a reducing environment to produce elemental metal distributed on carbon substrate. The product generally takes the shape of the carbon precursor.

Optimization of process parameters during carbonization for improved carbon fibre strength

NASA Astrophysics Data System (ADS)

Köhler, T.; Pursche, F.; Burscheidt, P.; Seide, G.; Gries, T.

2017-10-01

Based on their extraordinary properties, carbon fibres nowadays play a significant role in modern industries. In the last years carbon fibres are increasingly used for lightweight constructions in the energy or the transportation industry. However, a bigger market penetration of carbon fibres is still hindered by high prices (~ 22 /kg) [3]. One crucial step in carbon fibre production is the process of carbonization of stabilized fibres. However, the cause effect relationships of carbonization are nowadays not fully understood. Therefore, the main goal of this research work is the quantification of the cause-effect relationships of process parameters like temperature and residence time on carbon fibre strength.

Thermocatalytic process for CO.sub.2-free production of hydrogen and carbon from hydrocarbons

DOEpatents

Muradov, Nazim Z [Melbourne, FL

2011-08-23

A novel process and apparatus are disclosed for sustainable CO.sub.2-free production of hydrogen and carbon by thermocatalytic decomposition (dissociation, pyrolysis, cracking) of hydrocarbon fuels over carbon-based catalysts in the absence of air and/or water. The apparatus and thermocatalytic process improve the activity and stability of carbon catalysts during the thermocatalytic process and produce both high purity hydrogen (at least, 99.0 volume %) and carbon, from any hydrocarbon fuel, including sulfurous fuels. In a preferred embodiment, production of hydrogen and carbon is achieved by both internal and external activation of carbon catalysts. Internal activation of carbon catalyst is accomplished by recycling of hydrogen-depleted gas containing unsaturated and aromatic hydrocarbons back to the reactor. External activation of the catalyst can be achieved via surface gasification with hot combustion gases during catalyst heating. The process and apparatus can be conveniently integrated with any type of fuel cell to generate electricity.

High rates of organic carbon processing in the hyporheic zone of intermittent streams.

PubMed

Burrows, Ryan M; Rutlidge, Helen; Bond, Nick R; Eberhard, Stefan M; Auhl, Alexandra; Andersen, Martin S; Valdez, Dominic G; Kennard, Mark J

2017-10-16

Organic carbon cycling is a fundamental process that underpins energy transfer through the biosphere. However, little is known about the rates of particulate organic carbon processing in the hyporheic zone of intermittent streams, which is often the only wetted environment remaining when surface flows cease. We used leaf litter and cotton decomposition assays, as well as rates of microbial respiration, to quantify rates of organic carbon processing in surface and hyporheic environments of intermittent and perennial streams under a range of substrate saturation conditions. Leaf litter processing was 48% greater, and cotton processing 124% greater, in the hyporheic zone compared to surface environments when calculated over multiple substrate saturation conditions. Processing was also greater in more saturated surface environments (i.e. pools). Further, rates of microbial respiration on incubated substrates in the hyporheic zone were similar to, or greater than, rates in surface environments. Our results highlight that intermittent streams are important locations for particulate organic carbon processing and that the hyporheic zone sustains this fundamental process even without surface flow. Not accounting for carbon processing in the hyporheic zone of intermittent streams may lead to an underestimation of its local ecological significance and collective contribution to landscape carbon processes.

Low temperature stabilization process for production of carbon fiber having structural order

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

Rios, Orlando; McGuire, Michael Alan; More, Karren Leslie

A method for producing a carbon fiber, the method comprising: (i) subjecting a continuous carbon fiber precursor having a polymeric matrix in which strength-enhancing particles are incorporated to a stabilization process during which the carbon fiber precursor is heated to within a temperature range ranging from the glass transition temperature to no less than 20.degree. C. below the glass transition temperature of the polymeric matrix, wherein the maximum temperature employed in the stabilization process is below 400.degree. C., for a processing time within said temperature range of at least 1 hour in the presence of oxygen and in the presencemore » of a magnetic field of at least 1 Tesla, while said carbon fiber precursor is held under an applied axial tension; and (ii) subjecting the stabilized carbon fiber precursor, following step (i), to a carbonization process. The stabilized carbon fiber precursor, resulting carbon fiber, and articles made thereof are also described.« less

Trade-off between carbon emission and effluent quality of activated sludge processes under seasonal variations of wastewater temperature and mean cell retention time.

PubMed

Guo, Jingbo; Fu, Xin; Andrés Baquero, G; Sobhani, Reza; Nolasco, Daniel A; Rosso, Diego

2016-03-15

Over the seasonal cycles, the mean cell retention time (MCRT) of the activated sludge process is varied to compensate the wastewater temperature variations. The effects of these variations on the carbon footprint (CFP) and effluent quality index (EQI) of a conventional activated sludge (CAS) process and a nitrification/denitrification (NDN) process were quantified. The carbon emission included both biogenic and non-biogenic carbon. Carbon emissions of wasted biosolids management were also addressed. Our results confirmed that the effluent quality indicated by EQI was not necessarily improved by increasing MCRT. Higher MCRT increased the carbon emission and reduced excess sludge production, which decreased the potential for biogas energy recovery. The NDN process was preferable to the CAS process from the perspective of effluent quality. This consideration extended to the whole plant CFP if the N2O emitted during NDN was limited ([N2O]<1% [NH4(+)]removed) as the carbon emission per unit effluent quality achieved by NDN process is less than that of the CAS process. By putting forward carbon emission intensity (γ) derived from CFP and EQI, our work provides a quantitative tool for decision makers evaluating process alternatives when there is a trade-off between carbon emission and effluent quality. Copyright © 2015 Elsevier B.V. All rights reserved.

Modeling Global Soil Carbon and Soil Microbial Carbon by Integrating Microbial Processes into the Ecosystem Process Model TRIPLEX-GHG

DOE PAGES

Wang, Kefeng; Peng, Changhui; Zhu, Qiuan; ...

2017-09-28

Microbial physiology plays a critical role in the biogeochemical cycles of the Earth system. However, most traditional soil carbon models are lacking in terms of the representation of key microbial processes that control the soil carbon response to global climate change. In this study, the improved process-based model TRIPLEX-GHG was developed by coupling it with the new MEND (Microbial-ENzyme-mediated Decomposition) model to estimate total global soil organic carbon (SOC) and global soil microbial carbon. The new model (TRIPLEX-MICROBE) shows considerable improvement over the previous version (TRIPLEX-GHG) in simulating SOC. We estimated the global soil carbon stock to be approximately 1195more » Pg C, with 348 Pg C located in the high northern latitudes, which is in good agreement with the well-regarded Harmonized World Soil Database (HWSD) and the Northern Circumpolar Soil Carbon Database (NCSCD). We also estimated the global soil microbial carbon to be 21 Pg C, similar to the 23 Pg C estimated. We found that the microbial carbon quantity in the latitudinal direction showed reversions at approximately 30°N, near the equator and at 25°S. A sensitivity analysis suggested that the tundra ecosystem exhibited the highest sensitivity to a 1°C increase or decrease in temperature in terms of dissolved organic carbon (DOC), microbial biomass carbon (MBC) and mineral-associated organic carbon (MOC). Furthermore, our work represents the first step towards a new generation of ecosystem process models capable of integrating key microbial processes into soil carbon cycles.« less

Modeling Global Soil Carbon and Soil Microbial Carbon by Integrating Microbial Processes into the Ecosystem Process Model TRIPLEX-GHG

NASA Astrophysics Data System (ADS)

Wang, Kefeng; Peng, Changhui; Zhu, Qiuan; Zhou, Xiaolu; Wang, Meng; Zhang, Kerou; Wang, Gangsheng

2017-10-01

Microbial physiology plays a critical role in the biogeochemical cycles of the Earth system. However, most traditional soil carbon models are lacking in terms of the representation of key microbial processes that control the soil carbon response to global climate change. In this study, the improved process-based model TRIPLEX-GHG was developed by coupling it with the new MEND (Microbial-ENzyme-mediated Decomposition) model to estimate total global soil organic carbon (SOC) and global soil microbial carbon. The new model (TRIPLEX-MICROBE) shows considerable improvement over the previous version (TRIPLEX-GHG) in simulating SOC. We estimated the global soil carbon stock to be approximately 1195 Pg C, with 348 Pg C located in the high northern latitudes, which is in good agreement with the well-regarded Harmonized World Soil Database (HWSD) and the Northern Circumpolar Soil Carbon Database (NCSCD). We also estimated the global soil microbial carbon to be 21 Pg C, similar to the 23 Pg C estimated by Xu et al. (2014). We found that the microbial carbon quantity in the latitudinal direction showed reversions at approximately 30°N, near the equator and at 25°S. A sensitivity analysis suggested that the tundra ecosystem exhibited the highest sensitivity to a 1°C increase or decrease in temperature in terms of dissolved organic carbon (DOC), microbial biomass carbon (MBC), and mineral-associated organic carbon (MOC). However, our work represents the first step toward a new generation of ecosystem process models capable of integrating key microbial processes into soil carbon cycles.

Modeling Global Soil Carbon and Soil Microbial Carbon by Integrating Microbial Processes into the Ecosystem Process Model TRIPLEX-GHG

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

Wang, Kefeng; Peng, Changhui; Zhu, Qiuan

Microbial physiology plays a critical role in the biogeochemical cycles of the Earth system. However, most traditional soil carbon models are lacking in terms of the representation of key microbial processes that control the soil carbon response to global climate change. In this study, the improved process-based model TRIPLEX-GHG was developed by coupling it with the new MEND (Microbial-ENzyme-mediated Decomposition) model to estimate total global soil organic carbon (SOC) and global soil microbial carbon. The new model (TRIPLEX-MICROBE) shows considerable improvement over the previous version (TRIPLEX-GHG) in simulating SOC. We estimated the global soil carbon stock to be approximately 1195more » Pg C, with 348 Pg C located in the high northern latitudes, which is in good agreement with the well-regarded Harmonized World Soil Database (HWSD) and the Northern Circumpolar Soil Carbon Database (NCSCD). We also estimated the global soil microbial carbon to be 21 Pg C, similar to the 23 Pg C estimated. We found that the microbial carbon quantity in the latitudinal direction showed reversions at approximately 30°N, near the equator and at 25°S. A sensitivity analysis suggested that the tundra ecosystem exhibited the highest sensitivity to a 1°C increase or decrease in temperature in terms of dissolved organic carbon (DOC), microbial biomass carbon (MBC) and mineral-associated organic carbon (MOC). Furthermore, our work represents the first step towards a new generation of ecosystem process models capable of integrating key microbial processes into soil carbon cycles.« less

Carbon dioxide separation using adsorption with steam regeneration

DOEpatents

Elliott, Jeannine Elizabeth; Copeland, Robert James; Leta, Daniel P.; McCall, Patrick P.; Bai, Chuansheng; DeRites, Bruce A.

2016-11-29

A process for separating a carbon dioxide from a gas stream is disclosed. The process can include passing the gas stream over a sorbent that adsorbs the carbon dioxide by concentration swing adsorption and adsorptive displacement. The sorbent can be regenerated and the carbon dioxide recaptured by desorbing the carbon dioxide from the sorbent using concentration swing adsorption and desorptive displacement. A carbon dioxide separation system is also disclosed. Neither the system nor the process rely on temperature swing or pressure swing adsorption.

From decentralization to commonization of HIV healthcare resources: keys to reduction in health disparity and equitable distribution of health services in Nigeria.

PubMed

Oleribe, Obinna Ositadimma; Oladipo, Olabisi Abiodun; Ezieme, Iheaka Paul; Crossey, Mary Margaret Elizabeth; Taylor-Robinson, Simon David

2016-01-01

Access to quality care is essential for improved health outcomes. Decentralization improves access to healthcare services at lower levels of care, but it does not dismantle structural, funding and programming restrictions to access, resulting in inequity and inequality in population health. Unlike decentralization, Commonization Model of care reduces health inequalities and inequity, dismantles structural, funding and other program related obstacles to population health. Excellence and Friends Management Care Center (EFMC) using Commonization Model (CM), fully integrated HIV services into core health services in 121 supported facilities. This initiative improved access to care, treatment, support services, reduced stigmatization/discrimination, and improved uptake of HTC. We call on governments to adequately finance CM for health systems restructuring towards better health outcomes.

Simple method for resistance measurements on thin films and bulk of high T_c superconducting materials

NASA Astrophysics Data System (ADS)

Alzetta, G.; Arimondo, E.; Celli, R. M.; Fuso, F.

1994-08-01

Two experimental techniques for measuring resistivity behaviour of high T_c ceramic superconductors in bulk or thin films are described. Particular attention has been given to the development of a four point contact system, easy to use for reliable resistance measurements under repeated, wide thermal cycles. On expose deux méthodes de mesure de la résistivité des supraconducteurs HTc en forme de couches minces déposées sur un substrat ou des céramiques frittées. Le dispositif de mesure, qui a été réalisé avec quatre contacts élastiques, permet d'obtenir des résultats reproductibles dans de très larges intervalles de température.

Formation of functional asialoglycoprotein receptor after transfection with cDNAs encoding the receptor proteins.

PubMed Central

McPhaul, M; Berg, P

1986-01-01

The rat asialoglycoprotein receptor (ASGP-R) has been expressed in cultured rat hepatoma cells (HTC cells) after transfection with cloned cDNAs. Fluorescence-activated cell sorting of transfected cells was used to identify the functional cDNA clones and to isolate cells expressing the ASGP-R. Simultaneous or sequential transfections with two cloned cDNAs that encode related but distinctive polypeptide chains were needed to obtain ASGP-R activity; transfection with either cDNA alone failed to produce detectable ASGP-R. The affinity of transduced ASGP-R for asialo orosomucoid is less than that of the native rat ASGP-R, and the number of surface receptors in clones expressing ASGP-R is about one-fifth that found on rat hepatocytes. Images PMID:3466162

A tortuous route to a capable fatherhood: the experience of being a father to a child with severe haemophilia.

PubMed

Myrin Westesson, L; Sparud-Lundin, C; Wallengren, C; Baghaei, F

2015-11-01

Haemophilia is a chronic illness that affects the whole family as the child's reactions to the illness occur in interaction with the parents. Limited research has been conducted on how fathers of children with haemophilia experience their life situation. The aim of this study was to describe the lived experience of being a father to a child with severe haemophilia. Individual, qualitative interviews were conducted with 14 fathers of 17 children with severe Haemophilia A. Data were analysed by means of a phenomenological hermeneutic method, including naïve reading, structural analysis and comprehensive interpretation. The results revealed that the fathers gradually grew into fatherhood through a process that can be explained in the metaphor, 'A tortuous road to a capable fatherhood'. The fathers experienced sorrow, powerlessness, concern and loss of a regular fatherhood after the child's diagnosis. The loss of an envisaged fatherhood emerged as the greatest sorrow of being a father to a child with haemophilia. When home treatment with factor concentrates functioned without the involvement of Health Care Personal (HCP), the fathers' sense of insufficiency decreased. A sense of being a capable father was associated with a sense of independence and control of one's life situation. Support from the Haemophilia Treatment Centre (HTC) in the learning process is essential for both parents of a child with severe haemophilia. Awareness of the fathers' struggle to feel capable is also vital while supporting the family in the first years after diagnosis. © 2015 John Wiley & Sons Ltd.

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.

40 CFR 458.40 - Applicability; description of the carbon black lamp process subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 31 2013-07-01 2013-07-01 false Applicability; description of the carbon black lamp process subcategory. 458.40 Section 458.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Lamp Process...

40 CFR 458.40 - Applicability; description of the carbon black lamp process subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Applicability; description of the carbon black lamp process subcategory. 458.40 Section 458.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Lamp Process...

Gas-solid carbonation as a current alternative origin for carbonates in Martian regolith

NASA Astrophysics Data System (ADS)

Garenne, A.; Montes-Hernandez, G.; Beck, P.; Schmitt, B.; Brissaud, O.

2011-12-01

Carbonates are abundant sedimentary minerals at the surface and sub-surface of Earth and they have been proposed as tracers of liquid water in extraterrestrial environments (e.g. at Mars surface). Its formation mechanism is since generally associated with aqueous alteration processes. Recently, carbonates minerals have been discovered on Mars surface by different orbital or rovers missions. In particular, the phoenix mission has measured from 1 to 5% of calcium carbonate (calcite type). These occurrences have been reported in area were the relative humidity is significantly high (Boynton et al., 2009). The small concentration of carbonates suggests an alternative process than carbonation in aqueous conditions. Such an observation might rather point toward a possible formation mechanism by dust-gas reaction under current Martian conditions. For this reason, in the present study, we designed an experimental setup consisting of an infrared microscope coupled to a cryogenic reaction cell (IR-CryoCell setup) in order to investigate the gas-solid carbonation of three different mineral precursors for carbonates (Ca and Mg hydroxides, and a hydrated Ca silicate formed from Ca2SiO4) at low temperature (from -10 to 25°C) and at reduced CO2 pressure (from 100 to 1000 mbar). These mineral materials are crucial precursors to form respective Ca and Mg carbonates in humid environments (0 < relative humidity < 100%) at dust-CO2 or dust-water ice-CO2 interfaces. The results have revealed a significant and fast carbonation process for Ca hydroxide and hydrated Ca silicate. Conversely, slight carbonation process was observed for Mg hydroxide. These results suggest that gas-solid carbonation process or carbonate formation at the dust-water ice-CO2 interfaces could be a currently active Mars surface process. We note that the carbonation process at low temperature (<0°C) described in the present study could also have important implications on the dust-water ice-CO2 interactions in cold terrestrial environments (e.g. Antarctic).

Fabrication and processing of high-strength densely packed carbon nanotube yarns without solution processes.

PubMed

Liu, Kai; Zhu, Feng; Liu, Liang; Sun, Yinghui; Fan, Shoushan; Jiang, Kaili

2012-06-07

Defects of carbon nanotubes, weak tube-tube interactions, and weak carbon nanotube joints are bottlenecks for obtaining high-strength carbon nanotube yarns. Some solution processes are usually required to overcome these drawbacks. Here we fabricate ultra-long and densely packed pure carbon nanotube yarns by a two-rotator twisting setup with the aid of some tensioning rods. The densely packed structure enhances the tube-tube interactions, thus making high tensile strengths of carbon nanotube yarns up to 1.6 GPa. We further use a sweeping laser to thermally treat as-produced yarns for recovering defects of carbon nanotubes and possibly welding carbon nanotube joints, which improves their Young's modulus by up to ∼70%. The spinning and laser sweeping processes are solution-free and capable of being assembled together to produce high-strength yarns continuously as desired.

Production of long chain alkyl esters from carbon dioxide and electricity by a two-stage bacterial process.

PubMed

Lehtinen, Tapio; Efimova, Elena; Tremblay, Pier-Luc; Santala, Suvi; Zhang, Tian; Santala, Ville

2017-11-01

Microbial electrosynthesis (MES) is a promising technology for the reduction of carbon dioxide into value-added multicarbon molecules. In order to broaden the product profile of MES processes, we developed a two-stage process for microbial conversion of carbon dioxide and electricity into long chain alkyl esters. In the first stage, the carbon dioxide is reduced to organic compounds, mainly acetate, in a MES process by Sporomusa ovata. In the second stage, the liquid end-products of the MES process are converted to the final product by a second microorganism, Acinetobacter baylyi in an aerobic bioprocess. In this proof-of-principle study, we demonstrate for the first time the bacterial production of long alkyl esters (wax esters) from carbon dioxide and electricity as the sole sources of carbon and energy. The process holds potential for the efficient production of carbon-neutral chemicals or biofuels. Copyright © 2017 Elsevier Ltd. All rights reserved.

Carbon-based composite electrocatalysts for low temperature fuel cells

DOEpatents

Popov, Branko N [Columbia, SC; Lee, Jog-Won [Columbia, SC; Subramanian, Nalini P [Kennesaw, GA; Kumaraguru, Swaminatha P [Honeoye Falls, NY; Colon-Mercado, Hector R [Columbia, SC; Nallathambi, Vijayadurga [T-Nagar, IN; Li, Xuguang [Columbia, SC; Wu, Gang [West Columbia, SC

2009-12-08

A process for synthesis of a catalyst is provided. The process includes providing a carbon precursor material, oxidizing the carbon precursor material whereby an oxygen functional group is introduced into the carbon precursor material, and adding a nitrogen functional group into the oxidized carbon precursor material.

Technical and economical evaluation of carbon dioxide capture and conversion to methanol process

NASA Astrophysics Data System (ADS)

Putra, Aditya Anugerah; Juwari, Handogo, Renanto

2017-05-01

Phenomenon of global warming, which is indicated by increasing of earth's surface temperature, is caused by high level of greenhouse gases level in the atmosphere. Carbon dioxide, which increases year by year because of high demand of energy, gives the largest contribution in greenhouse gases. One of the most applied solution to mitigate carbon dioxide level is post-combustion carbon capture technology. Although the technology can absorb up to 90% of carbon dioxide produced, some worries occur that captured carbon dioxide that is stored underground will be released over time. Utilizing captured carbon dioxide could be a promising solution. Captured carbon dioxide can be converted into more valuable material, such as methanol. This research will evaluate the conversion process of captured carbon dioxide to methanol, technically and economically. From the research, it is found that technically methanol can be made from captured carbon dioxide. Product gives 25.6905 kg/s flow with 99.69% purity of methanol. Economical evaluation of the whole conversion process shows that the process is economically feasible. The capture and conversion process needs 176,101,157.69 per year for total annual cost and can be overcome by revenue gained from methanol product sales.

Self-assembly of single-wall carbon nanotubes during the cooling process of hot carbon gas.

PubMed

Wen, Yushi; Zheng, Ke; Long, Xinping; Li, Ming; Xue, Xianggui; Dai, Xiaogan; Deng, Chuan

2018-04-25

In this work, self-assembly mechanism of single-wall carbon nanotube (SWCNT) during the annealing process of hot gaseous carbon is presented using reactive force field (ReaxFF)-based reactive molecular simulations. A series of simulations were performed on the evolution of reactive carbon gas. The simulation results show that the reactive carbon gas can be assembled into regular SWCNT without a catalyst. Five distinct stages of SWCNT self-assembly are proposed. For some initial configurations, the CNT was found to spin at an ultra-high rate after the nucleation. Graphical abstract Self-assembly process of single-wall carbon nanotube from the annealing of hot gaseous carbon.

Process for Making Carbon-Carbon Turbocharger Housing Unit for Intermittent Combustion Engines

NASA Technical Reports Server (NTRS)

Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

1999-01-01

An improved. lightweight, turbine housing unit for an intermittent combustion reciprocating internal combustion engine turbocharger is prepared from a lay-up or molding of carbon-carbon composite materials in a single-piece or two-piece process. When compared to conventional steel or cast iron, the use of carbon-carbon composite materials in a turbine housing unit reduces the overall weight of the engine and reduces the heat energy loss used in the turbo-charging process. This reduction in heat energy loss and weight reduction provides for more efficient engine operation.

Energy efficient solvent regeneration process for carbon dioxide capture

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

Zhou, Shaojun; Meyer, Howard S.; Li, Shiguang

A process for removing carbon dioxide from a carbon dioxide-loaded solvent uses two stages of flash apparatus. Carbon dioxide is flashed from the solvent at a higher temperature and pressure in the first stage, and a lower temperature and pressure in the second stage, and is fed to a multi-stage compression train for high pressure liquefaction. Because some of the carbon dioxide fed to the compression train is already under pressure, less energy is required to further compress the carbon dioxide to a liquid state, compared to conventional processes.

Sequestering CO2 in the Built Environment

NASA Astrophysics Data System (ADS)

Constantz, B. R.

2009-12-01

Calera’s Carbonate Mineralization by Aqueous Precipitation (CMAP) technology with beneficial reuse has been called, “game-changing” by Carl Pope, Director of the Sierra Club. Calera offers a solution to the scale of the carbon problem. By capturing carbon into the built environment through carbonate mineralization, Calera provides a sound and cost-effective alternative to Geologic Sequestration and Terrestrial Sequestration. The CMAP technology permanently converts carbon dioxide into a mineral form that can be stored above ground, or used as a building material. The process produces a suite of carbonate-containing minerals of various polymorphic forms. Calera product can be substituted into blends with ordinary Portland cements and used as aggregate to produce concrete with reduced carbon, carbon neutral, or carbon negative footprints. For each ton of product produced, approximately half a ton of carbon dioxide can be sequestered using the Calera process. Coal and natural gas are composed of predominately istopically light carbon, as the carbon in the fuel is plant-derived. Thus, power plant CO2 emissions have relatively low δ13C values.The carbon species throughout the CMAP process are identified through measuring the inorganic carbon content, δ13C values of the dissolved carbonate species, and the product carbonate minerals. Measuring δ13C allows for tracking the flue gas CO2 throughout the capture process. Initial analysis of the capture of propane flue gas (δ13C ˜ -25 ‰) with seawater (δ13C ˜ -10 ‰) and industrial brucite tailings from a retired magnesium oxide plant in Moss Landing, CA (δ13C ˜ -7 ‰ from residual calcite) produced carbonate mineral products with a δ13C value of ˜ -20 ‰. This isotopically light carbon, transformed from flue gas to stable carbonate minerals, can be transferred and tracked through the capture process, and finally to the built environment. CMAP provides an economical solution to global warming by producing a usable product. While the cost of this process may, in some cases, exceed the selling price of the resultant materials, the value produced combined with available carbon credits makes this CMAP technology economically and environmentally sustainable. Calera operates a pilot plant in Moss Landing, CA, which is within the Monterey Bay Marine Sanctuary. The pilot plant is complete with a coal-fired burner simulator (CFBS) and laboratory. During operation, seawater is drawn in and subsequently combined with a variety of natural and manufactured minerals. Propane or coal flue gas from the CFBS is then contacted with the slurry suspension. The precipitated minerals are separated from the seawater and are further processed to produce cement or other building materials. After the seawater flows through the Calera process, it is returned to the ocean largely unchanged, with the exception of being calcium and magnesium depleted. An overview of the process, reporting the δ13C values throughout the CMAP process, along with the risk involved in changing regulations will be presented.

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.

Kinetic Monte Carlo (kMC) simulation of carbon co-implant on pre-amorphization process.

PubMed

Park, Soonyeol; Cho, Bumgoo; Yang, Seungsu; Won, Taeyoung

2010-05-01

We report our kinetic Monte Carlo (kMC) study of the effect of carbon co-implant on the pre-amorphization implant (PAL) process. We employed BCA (Binary Collision Approximation) approach for the acquisition of the initial as-implant dopant profile and kMC method for the simulation of diffusion process during the annealing process. The simulation results implied that carbon co-implant suppresses the boron diffusion due to the recombination with interstitials. Also, we could compare the boron diffusion with carbon diffusion by calculating carbon reaction with interstitial. And we can find that boron diffusion is affected from the carbon co-implant energy by enhancing the trapping of interstitial between boron and interstitial.

An easily accessible carbon material derived from carbonization of polyacrylonitrile ultrathin films: ambipolar transport properties and application in a CMOS-like inverter.

PubMed

Jiao, Fei; Zhang, Fengjiao; Zang, Yaping; Zou, Ye; Di, Chong'an; Xu, Wei; Zhu, Daoben

2014-03-04

Ultrathin carbon films were prepared by carbonization of a solution processed polyacrylonitrile (PAN) film in a moderate temperature range (500-700 °C). The films displayed balanced hole (0.50 cm(2) V(-1) s(-1)) and electron mobilities (0.20 cm(2) V(-1) s(-1)) under ambient conditions. Spectral characterization revealed that the electrical transport is due to the formation of sp(2) hybridized carbon during the carbonization process. A CMOS-like inverter demonstrated the potential application of this material in the area of carbon electronics, considering its processability and low-cost.

A qualitative study of the determinants of HIV guidelines implementation in two south-eastern districts of Tanzania.

PubMed

Mwangome, Mary N; Geubbels, Eveline; Wringe, Alison; Todd, Jim; Klatser, Paul; Dieleman, Marjolein

2017-07-01

Current HIV policies in Tanzania have adopted the three long-term impact results of zero new infections, zero HIV deaths and zero stigma and discrimination. Strategies to reach these results include scaling-up HIV Testing and Counselling (HTC); Preventing Mother-To-Child Transmission (PMTCT); and strengthening Care and Treatment Clinic (CTC) services. Previous studies showed that HIV policy and guideline recommendations were not always implemented in rural South Tanzania. This study aims to identify the determinants of HIV guideline implementation. A qualitative study of 23 semi-structured interviews with facility in-charges; healthcare workers; district, regional and national HIV coordinators was conducted. Five health facilities were purposively selected by level, ownership and proximity to district headquarters. Interviews were analysed according to Fleuren's five determinants of innovation uptake related to: strategies used in guideline development and dissemination; guideline characteristics; the guideline implementing organization; guideline users; and the socio-cultural and regulatory context. None of the facilities had the HTC national guideline document. Non-involvement of providers in revisions and weak planning for guideline dissemination impeded their implementation. Lengthy guidelines and those written in English were under-used, and activities perceived to be complicated, like WHO-staging, were avoided. Availability of staff and lack of supplies like test kits and medication impeded implementation. Collaboration between facilities enhanced implementation, as did peer-support among providers. Provider characteristics including education level, knowledge of, and commitment to the guideline influenced implementation. According to providers, determinants of clients' service use included gender norms, stigma, trust and perceived benefits. The regulatory context prohibited private hospitals from buying HIV supplies. Being tools for bringing policies to practice, national guidelines are crucial in the efforts towards the three zeros. Strategies to improve providers' adherence to guidelines should include development of clearer guideline dissemination plans, strengthening of the health system, and possibly addressing of provider-perceived patient-level barriers to utilizing HIV services. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine.

Co-infection of Haemonchus contortus and Trichostrongylus spp. among livestock in Malaysia as revealed by amplification and sequencing of the internal transcribed spacer II DNA region

PubMed Central

2014-01-01

Background Haemonchus contortus and Trichostrongylus spp. are reported to be the most prevalent and highly pathogenic parasites in livestock, particularly in small ruminants. However, the routine conventional tool used in Malaysia could not differentiate the species accurately and therefore limiting the understanding of the co-infections between these two genera among livestock in Malaysia. This study is the first attempt to identify the strongylids of veterinary importance in Malaysia (i.e., H. contortus and Trichostrongylus spp.) by amplification and sequencing of the Internal Transcribed Spacer II DNA region. Results Overall, 118 (cattle: 11 of 98 or 11.2%; deer: 4 of 70 or 5.7%; goats: 99 of 157 or 63.1%; swine: 4 of 91 or 4.4%) out of the 416 collected fecal samples were microscopy positive with strongylid infection. The PCR and sequencing results demonstrated that 93 samples (1 or 25.0% of deer; 92 or 92.9% of goats) contained H. contortus. In addition, Trichostrongylus colubriformis was observed in 75 (75.8% of 99) of strongylid infected goats and Trichostrongylus axei in 4 (4.0%) of 99 goats and 2 (50.0%) of 4 deer. Based on the molecular results, co-infection of H. contortus and Trichostrongylus spp. (H. contortus + T. colubriformis denoted as HTC; H. contortus + T. axei denoted as HTA) were only found in goats. Specifically, HTC co-infections have higher rate (71 or 45.2% of 157) compared to HTA co-infections (3 or 1.9% of 157). Conclusions The present study is the first molecular identification of strongylid species among livestock in Malaysia which is essential towards a better knowledge of the epidemiology of gastro-intestinal parasitic infection among livestock in the country. Furthermore, a more comprehensive or nationwide molecular-based study on gastro-intestinal parasites in livestock should be carried out in the future, given that molecular tools could assist in improving diagnosis of veterinary parasitology in Malaysia due to its high sensitivity and accuracy. PMID:24502557

Identifying injection drug use and estimating population size of people who inject drugs using healthcare administrative datasets.

PubMed

Janjua, Naveed Zafar; Islam, Nazrul; Kuo, Margot; Yu, Amanda; Wong, Stanley; Butt, Zahid A; Gilbert, Mark; Buxton, Jane; Chapinal, Nuria; Samji, Hasina; Chong, Mei; Alvarez, Maria; Wong, Jason; Tyndall, Mark W; Krajden, Mel

2018-05-01

Large linked healthcare administrative datasets could be used to monitor programs providing prevention and treatment services to people who inject drugs (PWID). However, diagnostic codes in administrative datasets do not differentiate non-injection from injection drug use (IDU). We validated algorithms based on diagnostic codes and prescription records representing IDU in administrative datasets against interview-based IDU data. The British Columbia Hepatitis Testers Cohort (BC-HTC) includes ∼1.7 million individuals tested for HCV/HIV or reported HBV/HCV/HIV/tuberculosis cases in BC from 1990 to 2015, linked to administrative datasets including physician visit, hospitalization and prescription drug records. IDU, assessed through interviews as part of enhanced surveillance at the time of HIV or HCV/HBV diagnosis from a subset of cases included in the BC-HTC (n = 6559), was used as the gold standard. ICD-9/ICD-10 codes for IDU and injecting-related infections (IRI) were grouped with records of opioid substitution therapy (OST) into multiple IDU algorithms in administrative datasets. We assessed the performance of IDU algorithms through calculation of sensitivity, specificity, positive predictive, and negative predictive values. Sensitivity was highest (90-94%), and specificity was lowest (42-73%) for algorithms based either on IDU or IRI and drug misuse codes. Algorithms requiring both drug misuse and IRI had lower sensitivity (57-60%) and higher specificity (90-92%). An optimal sensitivity and specificity combination was found with two medical visits or a single hospitalization for injectable drugs with (83%/82%) and without OST (78%/83%), respectively. Based on algorithms that included two medical visits, a single hospitalization or OST records, there were 41,358 (1.2% of 11-65 years individuals in BC) recent PWID in BC based on health encounters during 3- year period (2013-2015). Algorithms for identifying PWID using diagnostic codes in linked administrative data could be used for tracking the progress of programing aimed at PWID. With population-based datasets, this tool can be used to inform much needed estimates of PWID population size. Copyright © 2018 Elsevier B.V. All rights reserved.

Production of activated carbon by using pyrolysis process in an ammonia atmosphere

NASA Astrophysics Data System (ADS)

Indayaningsih, N.; Destyorini, F.; Purawiardi, R. I.; Insiyanda, D. R.; Widodo, H.

2017-04-01

Activated carbon is materials that have wide applications, including supercapacitor materials, absorbent in chemical industry, and absorbent material in the chemical industry. This study has carried out for the manufacturing of activated carbon from inexpensive materials through efficient processes. Carbon material was made from coconut fibers through pyrolysis process at temperature of 650, 700, 750 and 800°C. Aim of this study was to obtain carbon material that has a large surface area. Pyrolysis process is carried out in an inert atmosphere (N2 gas) at a temperature of 450°C for 30 minutes, followed by pyrolysis process in an ammonia atmosphere at 800°C for 2 hours. The pyrolysis results showed that the etching process in ammonia is occurred; as it obtained some greater surface area when compared with the pyrolisis process in an atmosphere by inert gas only. The resulted activated carbon also showed to have good properties in surface area and total pore volume.

Magnetic carbon nanostructures: microwave energy-assisted pyrolysis vs. conventional pyrolysis.

PubMed

Zhu, Jiahua; Pallavkar, Sameer; Chen, Minjiao; Yerra, Narendranath; Luo, Zhiping; Colorado, Henry A; Lin, Hongfei; Haldolaarachchige, Neel; Khasanov, Airat; Ho, Thomas C; Young, David P; Wei, Suying; Guo, Zhanhu

2013-01-11

Magnetic carbon nanostructures from microwave assisted- and conventional-pyrolysis processes are compared. Unlike graphitized carbon shells from conventional heating, different carbon shell morphologies including nanotubes, nanoflakes and amorphous carbon were observed. Crystalline iron and cementite were observed in the magnetic core, different from a single cementite phase from the conventional process.

Method for synthesizing carbon nanotubes

DOEpatents

Fan, Hongyou

2012-09-04

A method for preparing a precursor solution for synthesis of carbon nanomaterials, where a polar solvent is added to at least one block copolymer and at least one carbohydrate compound, and the precursor solution is processed using a self-assembly process and subsequent heating to form nanoporous carbon films, porous carbon nanotubes, and porous carbon nanoparticles.

Silk-regulated hierarchical hollow magnetite/carbon nanocomposite spheroids for lithium-ion battery anodes.

PubMed

Sheng, Weiqin; Zhu, Guobin; Kaplan, David L; Cao, Chuanbao; Zhu, Hesun; Lu, Qiang

2015-03-20

Hierarchical olive-like structured carbon-Fe3O4 nanocomposite particles composed of a hollow interior and a carbon coated surface are prepared by a facile, silk protein-assisted hydrothermal method. Silk nanofibers as templates and carbon precursors first regulate the formation of hollow Fe2O3 microspheres and then they are converted into carbon by a reduction process into Fe3O4. This process significantly simplifies the fabrication and carbon coating processes to form complex hollow structures. When tested as anode materials for lithium-ion batteries, these hollow carbon-coated particles exhibit high capacity (900 mAh g(-1)), excellent cycle stability (180 cycles) and rate performance due to their unique hierarchical hollow structure and carbon coating.

Photoluminescence study of carbon dots from ginger and galangal herbs using microwave technique

NASA Astrophysics Data System (ADS)

Isnaeni; Rahmawati, I.; Intan, R.; Zakaria, M.

2018-03-01

Carbon dots are new type of fluorescent nanoparticle that can be synthesis easily from natural sources. We have synthesized carbon dots from ginger and galangal herbs using microwave technique and studied their optical properties. We synthesized colloidal carbon dots in water solvent by varying microwave processing time. UV-Vis absorbance, photoluminescence, time-resolved photoluminescence, and transmission electron microscope were utilized to study properties of carbon dots. We found that microwave processing time significantly affect optical properties of synthesized carbon dots. UV-Vis absorbance spectra and time-resolved photoluminescence results show that luminescent of carbon dots is dominated by recombination process from n-π* surface energy level. With further development, these carbon dots are potential for several applications.

HF treatment effect for carbon deposition on silicon (111) by DC sputtering technique

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

Aji, A. S., E-mail: aji.ravazes70@gmail.com; Darma, Y., E-mail: aji.ravazes70@gmail.com

Surface modifications of Si (111) substrate by HF solution for thin film carbon deposition have been systematically studied. Thin film carbon on Si (111) has been deposited using DC Unbalanced Magnetron Sputtering with carbon pellet doped by 5% Fe as the target. EDAX characterization confirmed that the carbon fraction on Si substrate much higher by dipping a clean Si substrate by HF solution before sputtering process in comparison with carbon fraction on Si substrate just after conventional RCA. Moreover, SEM and AFM images show the uniform thin film carbon on Si with HF treatment, in contrast to the Si withoutmore » HF solution treatment. These experimental results suggest that HF treatment of Si surface provide Si-H bonds on top Si surface that useful to enhance the carbon deposition during sputtering process. Furthermore, we investigate the thermal stability of thin film carbon on Si by thermal annealing process up to 900 °C. Atomic arrangements during annealing process were characterized by Raman spectroscopy. Raman spectra indicate that thin film carbon on Si is remaining unchanged until 600 °C and carbon atoms start to diffuse toward Si substrate after annealing at 900 °C.« less

Enhanced biological phosphorus removal with different carbon sources.

PubMed

Shen, Nan; Zhou, Yan

2016-06-01

Enhanced biological phosphorus removal (EBPR) process is one of the most economical and sustainable methods for phosphorus removal from wastewater. However, the performance of EBPR can be affected by available carbon sources types in the wastewater that may induce different functional microbial communities in the process. Glycogen accumulating organisms (GAOs) and polyphosphate accumulating organisms (PAOs) are commonly found by coexisting in the EBPR process. Predominance of GAO population may lead to EBPR failure due to the competition on carbon source with PAO without contributing phosphorus removal. Carbon sources indeed play an important role in alteration of PAOs and GAOs in EBPR processes. Various types of carbon sources have been investigated for EBPR performance. Certain carbon sources tend to enrich specific groups of GAOs and/or PAOs. This review summarizes the types of carbon sources applied in EBPR systems and highlights the roles of these carbon sources in PAO and GAO competition. Both single (e.g., acetate, propionate, glucose, ethanol, and amino acid) and complex carbon sources (e.g., yeast extract, peptone, and mixed carbon sources) are discussed in this review. Meanwhile, the environmental friendly and economical carbon sources that are derived from waste materials, such as crude glycerol and wasted sludge, are also discussed and compared.

Design principle for efficient charge separation at the donor-acceptor interface for high performance organic solar cell device

NASA Astrophysics Data System (ADS)

Nie, Wanyi; Gupta, Gautam; Crone, Brian; Wang, Hsing-Lin; Mohite, Aditya; MPA-11 Material synthesis and integrated device Team; MPA-chemistry Team

2014-03-01

The performance of donor (D) /acceptor (A) structure based organic electronic devices, such as solar cell, light emitting devices etc., relays on the charge transfer process at the interface dramatically. In organic solar cell, the photo-induced electron-hole pair is tightly bonded and will form a charge transfer (CT) state at the D/A interface after dissociation. There is a large chance for them to recombine through CT state and thus is a major loss that limit the overall performance. Here, we report three different strategies that allow us to completely suppress the exciplex (or charge transfer state) recombination between any D/A system. We observe that the photocurrent increases by 300% and the power conversion efficiency increases by 4-5 times simply by inserting a spacer layer in the form of an a) insulator b) Oliogomer or using a c) heavy atom at the donor-acceptor interface in a P3HT/C60 bilayer device. By using those different functional mono layers, we successfully suppressed the exciplex recombination in evidence of increased photocurrent and open circuit voltage. Moreover, these strategies are applicable universally to any donor-acceptor interface. And we demonstrated such strategies in a bulk-heterojunction device which improved the power conversion efficiency from 3.5% up to 4.6%.

Process-oriented modelling to identify main drivers of erosion-induced carbon fluxes

NASA Astrophysics Data System (ADS)

Wilken, Florian; Sommer, Michael; Van Oost, Kristof; Bens, Oliver; Fiener, Peter

2017-05-01

Coupled modelling of soil erosion, carbon redistribution, and turnover has received great attention over the last decades due to large uncertainties regarding erosion-induced carbon fluxes. For a process-oriented representation of event dynamics, coupled soil-carbon erosion models have been developed. However, there are currently few models that represent tillage erosion, preferential water erosion, and transport of different carbon fractions (e.g. mineral bound carbon, carbon encapsulated by soil aggregates). We couple a process-oriented multi-class sediment transport model with a carbon turnover model (MCST-C) to identify relevant redistribution processes for carbon dynamics. The model is applied for two arable catchments (3.7 and 7.8 ha) located in the Tertiary Hills about 40 km north of Munich, Germany. Our findings indicate the following: (i) redistribution by tillage has a large effect on erosion-induced vertical carbon fluxes and has a large carbon sequestration potential; (ii) water erosion has a minor effect on vertical fluxes, but episodic soil organic carbon (SOC) delivery controls the long-term erosion-induced carbon balance; (iii) delivered sediments are highly enriched in SOC compared to the parent soil, and sediment delivery is driven by event size and catchment connectivity; and (iv) soil aggregation enhances SOC deposition due to the transformation of highly mobile carbon-rich fine primary particles into rather immobile soil aggregates.

Synthesis of a Carbon-activated Microfiber from Spider Webs Silk

NASA Astrophysics Data System (ADS)

Taer, E.; Mustika, W. S.; Taslim, R.

2017-03-01

Carbon fiber of spider web silk has been produced through the simple carbonization process. Cobwebs are a source of strong natural fiber, flexible and micrometer in size. Preparation of micro carbon fiber from spider webs that consist of carbonization and activation processes. Carbonization was performed in N2 gas environment by multi step heating profile up to temperature of 400 °C, while the activation process was done by using chemical activation with KOH activating agent assistance. Measurement of physical properties was conducted on the surface morphology, element content and the degree of crystallinity. The measurement results found that micro carbon fiber from spider webs has a diameter in the range of 0.5 -25 micrometers. It is found that the carbon-activated microfiber takes the amorphous form with the carbon content of 84 %.

Process for producing an activated carbon adsorbent with integral heat transfer apparatus

NASA Technical Reports Server (NTRS)

Jones, Jack A. (Inventor); Yavrouian, Andre H. (Inventor)

1996-01-01

A process for producing an integral adsorbent-heat exchanger apparatus useful in ammonia refrigerant heat pump systems. In one embodiment, the process wets an activated carbon particles-solvent mixture with a binder-solvent mixture, presses the binder wetted activated carbon mixture on a metal tube surface and thereafter pyrolyzes the mixture to form a bonded activated carbon matrix adjoined to the tube surface. The integral apparatus can be easily and inexpensively produced by the process in large quantities.

Carbon Cycling and Biosequestration Integrating Biology and Climate Through Systems Science Report from the March 2008 Workshop

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

Graber, J.; Amthor, J.; Dahlman, R.

2008-12-01

One of the most daunting challenges facing science in the 21st Century is to predict how Earth's ecosystems will respond to global climate change. The global carbon cycle plays a central role in regulating atmospheric carbon dioxide (CO{sub 2}) levels and thus Earth's climate, but our basic understanding of the myriad of tightly interlinked biological processes that drive the global carbon cycle remains limited at best. Whether terrestrial and ocean ecosystems will capture, store, or release carbon is highly dependent on how changing climate conditions affect processes performed by the organisms that form Earth's biosphere. Advancing our knowledge of biologicalmore » components of the global carbon cycle is thus crucial to predicting potential climate change impacts, assessing the viability of climate change adaptation and mitigation strategies, and informing relevant policy decisions. Global carbon cycling is dominated by the paired biological processes of photosynthesis and respiration. Photosynthetic plants and microbes of Earth's land-masses and oceans use solar energy to transform atmospheric CO{sub 2} into organic carbon. The majority of this organic carbon is rapidly consumed by plants or microbial decomposers for respiration and returned to the atmosphere as CO{sub 2}. Coupling between the two processes results in a near equilibrium between photosynthesis and respiration at the global scale, but some fraction of organic carbon also remains in stabilized forms such as biomass, soil, and deep ocean sediments. This process, known as carbon biosequestration, temporarily removes carbon from active cycling and has thus far absorbed a substantial fraction of anthropogenic carbon emissions.« less

Production of Low Cost Carbon-Fiber through Energy Optimization of Stabilization Process.

PubMed

Golkarnarenji, Gelayol; Naebe, Minoo; Badii, Khashayar; Milani, Abbas S; Jazar, Reza N; Khayyam, Hamid

2018-03-05

To produce high quality and low cost carbon fiber-based composites, the optimization of the production process of carbon fiber and its properties is one of the main keys. The stabilization process is the most important step in carbon fiber production that consumes a large amount of energy and its optimization can reduce the cost to a large extent. In this study, two intelligent optimization techniques, namely Support Vector Regression (SVR) and Artificial Neural Network (ANN), were studied and compared, with a limited dataset obtained to predict physical property (density) of oxidative stabilized PAN fiber (OPF) in the second zone of a stabilization oven within a carbon fiber production line. The results were then used to optimize the energy consumption in the process. The case study can be beneficial to chemical industries involving carbon fiber manufacturing, for assessing and optimizing different stabilization process conditions at large.

Production of Low Cost Carbon-Fiber through Energy Optimization of Stabilization Process

PubMed Central

Golkarnarenji, Gelayol; Naebe, Minoo; Badii, Khashayar; Milani, Abbas S.; Jazar, Reza N.; Khayyam, Hamid

2018-01-01

To produce high quality and low cost carbon fiber-based composites, the optimization of the production process of carbon fiber and its properties is one of the main keys. The stabilization process is the most important step in carbon fiber production that consumes a large amount of energy and its optimization can reduce the cost to a large extent. In this study, two intelligent optimization techniques, namely Support Vector Regression (SVR) and Artificial Neural Network (ANN), were studied and compared, with a limited dataset obtained to predict physical property (density) of oxidative stabilized PAN fiber (OPF) in the second zone of a stabilization oven within a carbon fiber production line. The results were then used to optimize the energy consumption in the process. The case study can be beneficial to chemical industries involving carbon fiber manufacturing, for assessing and optimizing different stabilization process conditions at large. PMID:29510592

Formation mechanism of a silicon carbide coating for a reinforced carbon-carbon composite

NASA Technical Reports Server (NTRS)

Rogers, D. C.; Shuford, D. M.; Mueller, J. I.

1975-01-01

Results are presented for a study to determine the mechanisms involved in a high-temperature pack cementation process which provides a silicon carbide coating on a carbon-carbon composite. The process and materials used are physically and chemically analyzed. Possible reactions are evaluated using the results of these analytical data. The coating is believed to develop in two stages. The first is a liquid controlled phase process in which silicon carbide is formed due to reactions between molten silicon metal and the carbon. The second stage is a vapor transport controlled reaction in which silicon vapors react with the carbon. There is very little volume change associated with the coating process. The original thickness changes by less than 0.7%. This indicates that the coating process is one of reactive penetration. The coating thickness can be increased or decreased by varying the furnace cycle process time and/or temperature to provide a wide range of coating thicknesses.

Control of carbon balance in a silicon smelting furnace

DOEpatents

Dosaj, Vishu D.; Haines, Cathryn M.; May, James B.; Oleson, John D.

1992-12-29

The present invention is a process for the carbothermic reduction of silicon dioxide to form elemental silicon. Carbon balance of the process is assessed by measuring the amount of carbon monoxide evolved in offgas exiting the furnace. A ratio of the amount of carbon monoxide evolved and the amount of silicon dioxide added to the furnace is determined. Based on this ratio, the carbon balance of the furnace can be determined and carbon feed can be adjusted to maintain the furnace in carbon balance.

Kinetic Fractionation of Stable Isotopes in Carbonates on Mars: Terrestrial Analogs

NASA Technical Reports Server (NTRS)

Socki, Richard A.; Gibson, Everett K., Jr.; Golden, D. C.; Ming, Douglas W.; McKay, Gordon A.

2003-01-01

An ancient Martian hydrosphere consisting of an alkali-rich ocean would likely produce solid carbonate minerals through the processes of evaporation and/or freezing. We postulate that both (or either) of these kinetically-driven processes would produce carbonate minerals whose stable isotopic compositions are highly fractionated (enriched) with respect to the source carbon. Various scenarios have been proposed for carbonate formation on Mars, including high temperature formation, hydrothermal alteration, precipitation from evaporating brines, and cryogenic formation. 13C and 18O -fractionated carbonates have previously been shown to form kinetically under some of these conditions, ie.: 1) alteration by hydrothermal processes, 2) low temperature precipitation (sedimentary) from evaporating bicarbonate (brine) solutions, and 3) precipitation during the process of cryogenic freezing of bicarbonate-rich fluids. Here we examine several terrestrial field settings within the context of kinetically controlled carbonate precipitation where stable isotope enrichments have been observed.

Leveraging Emerging Technologies in Outreach for JWST

NASA Astrophysics Data System (ADS)

Meinke, Bonnie K.; Green, Joel D.; Smith, Louis Chad; Smith, Denise A.; Lawton, Brandon L.; Gough, Michael

2017-10-01

The James Webb Space Telescope (JWST) is NASA’s next great observatory, launching in October 2018. How will we maintain the prestige and cultural impact of the Hubble Space Telescope as the torch passes to Webb? Emerging technologies such as augmented (AR) and virtual reality (VR) bring the viewer into the data and introduce the telescope in previously unimaginable immersive detail. Adoption of mobile devices, many of which easily support AR and VR, has expanded access to information for wide swaths of the public. From software like Worldwide Telescope to hardware like the HTC Vive, immersive environments are providing new avenues for learning. If we develop materials properly tailored to these media, we can reach more diverse audiences than ever before. STScI is piloting tools related to JWST to showcase at DPS, and in local events, which I highlight here.

Condensation heat transfer correlation for water-ethanol vapor mixture flowing through a plate heat exchanger

NASA Astrophysics Data System (ADS)

Zhou, Weiqing; Hu, Shenhua; Ma, Xiangrong; Zhou, Feng

2018-04-01

Condensation heat transfer coefficient (HTC) as a function of outlet vapor quality was investigated using water-ethanol vapor mixture of different ethanol vapor concentrations (0%, 1%, 2%, 5%, 10%, 20%) under three different system pressures (31 kPa, 47 kPa, 83 kPa). A heat transfer coefficient was developed by applying multiple linear regression method to experimental data, taking into account the dimensionless numbers which represents the Marangoni condensation effects, such as Re, Pr, Ja, Ma and Sh. The developed correlation can predict the condensation performance within a deviation range from -22% to 32%. Taking PHE's characteristic into consideration and bringing in Ma number and Sh number, a new correlation was developed, which showed a much more accurate prediction, within a deviation from -3.2% to 7.9%.

A Carbon Cycle Model for the Social-Ecological Process in Coastal Wetland: A Case Study on Gouqi Island, East China

PubMed Central

Xiong, Lihu; Zhu, Wenjia

2017-01-01

Coastal wetlands offer many important ecosystem services both in natural and in social systems. How to simultaneously decrease the destructive effects flowing from human activities and maintaining the sustainability of regional wetland ecosystems are an important issue for coastal wetlands zones. We use carbon credits as the basis for regional sustainable developing policy-making. With the case of Gouqi Island, a typical coastal wetlands zone that locates in the East China Sea, a carbon cycle model was developed to illustrate the complex social-ecological processes. Carbon-related processes in natural ecosystem, primary industry, secondary industry, tertiary industry, and residents on the island were identified in the model. The model showed that 36780 tons of carbon is released to atmosphere with the form of CO2, and 51240 tons of carbon is captured by the ecosystem in 2014 and the three major resources of carbon emission are transportation and tourism development and seawater desalination. Based on the carbon-related processes and carbon balance, we proposed suggestions on the sustainable development strategy of Gouqi Island as coastal wetlands zone. PMID:28286690

A Carbon Cycle Model for the Social-Ecological Process in Coastal Wetland: A Case Study on Gouqi Island, East China.

PubMed

Li, Yanxia; Xiong, Lihu; Zhu, Wenjia

2017-01-01

Coastal wetlands offer many important ecosystem services both in natural and in social systems. How to simultaneously decrease the destructive effects flowing from human activities and maintaining the sustainability of regional wetland ecosystems are an important issue for coastal wetlands zones. We use carbon credits as the basis for regional sustainable developing policy-making. With the case of Gouqi Island, a typical coastal wetlands zone that locates in the East China Sea, a carbon cycle model was developed to illustrate the complex social-ecological processes. Carbon-related processes in natural ecosystem, primary industry, secondary industry, tertiary industry, and residents on the island were identified in the model. The model showed that 36780 tons of carbon is released to atmosphere with the form of CO 2 , and 51240 tons of carbon is captured by the ecosystem in 2014 and the three major resources of carbon emission are transportation and tourism development and seawater desalination. Based on the carbon-related processes and carbon balance, we proposed suggestions on the sustainable development strategy of Gouqi Island as coastal wetlands zone.

Liquid phase methanol reactor staging process for the production of methanol

DOEpatents

Bonnell, Leo W.; Perka, Alan T.; Roberts, George W.

1988-01-01

The present invention is a process for the production of methanol from a syngas feed containing carbon monoxide, carbon dioxide and hydrogen. Basically, the process is the combination of two liquid phase methanol reactors into a staging process, such that each reactor is operated to favor a particular reaction mechanism. In the first reactor, the operation is controlled to favor the hydrogenation of carbon monoxide, and in the second reactor, the operation is controlled so as to favor the hydrogenation of carbon dioxide. This staging process results in substantial increases in methanol yield.

Microbial respiration and DOC composition in leachates from Holocene and Pleistocene soils from the Kolyma River basin in Eastern Siberia

NASA Astrophysics Data System (ADS)

Lewis, K.; Schade, J. D.; Sobczak, W. V.; Holmes, R. M.; Zimov, N.; Bulygina, E. B.; Chandra, S.; Bunn, A. G.; Russell-Roy, L.; Seybold, E. C.

2010-12-01

Permafrost is generally considered a long-term sink for carbon that remains locked away from the global carbon cycle. Anthropogenic climate change is likely to lead to thawing of permafrost and deepening of the soil active layer. Consequently, this carbon sink may become unlocked and available for bacterial decomposition, returning stored carbon to the active carbon cycle, with potentially severe consequences for atmospheric CO2 concentrations. The Kolyma watershed, in the Eastern Siberian Arctic, is underlain by continuous permafrost, often referred to as Yedoma, which provides a unique environment to study potential consequences of permafrost thaw for carbon dynamics in aquatic and terrestrial ecosystems. In order to predict the potential consequences of a major carbon input from thawing permafrost, we assessed the relative bioavailabilty of soil carbon by measuring rates of microbial consumption and changes in DOM composition in soil leachates. At two spatially distinct sample sites, soil was collected throughout the profile from the active layer and from permafrost, including soils from both Holocene and Pleistocene-era permafrost. To evaluate the rates of carbon processing and potential linkages to N and P cycles, we conducted a series of bottle experiments in which we measured biological oxygen demand as a proxy for carbon processing and assessed changes in the composition of dissolved organic carbon using spectral analyses. Experiments were conducted on leachate collected from each soil type. Each experiment included treatments in which leachates were enriched with nitrogen and phosphorus to determine whether carbon processing in soils was nutrient limited. We found substantial variation in oxygen consumption, with Yedoma soils generally exhibiting higher rates than Holocene soils, suggesting higher concentrations of labile carbon. We found no evidence of nutrient limitation of carbon processing in any soil leachates. Spectral slope analysis suggests that carbon processing increased the proportion of heavy aromatic carbon compounds in all but one soil type, suggesting that small molecular weight compounds are consumed first. The exception was the most active Yedoma soil, which showed the opposite effect, indicating an increase in the proportion of small molecules due to the presence of a different, and perhaps more digestible, form of carbon. These results suggest strong spatial variation in the amount and form of available carbon, as well as qualitative differences in the dynamics of carbon processing.

Lead recovery from waste CRT funnel glass by high-temperature melting process.

PubMed

Hu, Biao; Hui, Wenlong

2018-02-05

In this research, a novel and effective process for waste CRT funnel glass treatment was developed. The key to this process is removal of lead from the CRT funnel glass by high-temperature melting process. Sodium carbonate powder was used as a fusion agent, sodium sulfide serves as a catalytic agent and carbon powder acts as reducing agent. Experimental results showed that lead recovery rate increased with an increase in the amount of added sodium carbonate, sodium sulfide, carbonate, temperature and holding time initially, and then reached a stable value. The maximum lead recovery rate was approximately 94%, when the optimum adding amount of sodium carbonate, sodium sulfide, carbonate, temperature and holding time were 25%, 8%, 3.6%, 1200°C and 120min, respectively. In the high-temperature melting process, lead silicate in the funnel glass was firstly reduced, and then removed. The glass slag can be made into sodium and potassium silicate by hydrolysis process. This study proposed a practical and economical process for recovery of lead and utilization of waste glass slag. Copyright © 2017 Elsevier B.V. All rights reserved.

Banking carbon: A review of organic carbon storage and physical factors influencing retention in floodplains and riparian ecosystems

Treesearch

Nicholas A. Sutfin; Ellen E. Wohl; Kathleen A. Dwire

2016-01-01

Rivers are dynamic components of the terrestrial carbon cycle and provide important functions in ecosystem processes. Although rivers act as conveyers of carbon to the oceans, rivers also retain carbon within riparian ecosystems along floodplains, with potential for long-term (> 102 years) storage. Research in ecosystem processing emphasizes the...

Facile preparation of porous carbon from coffee bean waste using low temperature solvothermal method

NASA Astrophysics Data System (ADS)

Baroroh, L. A. Al; Fitria, D.; Amal, M. I.; Wismogroho, A. S.; Widayatno, W. B.

2018-03-01

In this study, porous carbon made from coffee bean waste (CBW) was carbonized at 500 °C, 600 °C, and 700 °C to find effective temperature. It is verified from the IR spectrum that carbonization process at certain temperature can effectively break cellulose bonding and make aromatics functional group while preserving its carbon structure. The TG-DTA curve shows four stages of decomposition process and confirms most effective carbonization temperature. Activation process of as-carbonized CBW was carried out using solvothermal method in KOH and NH4OH steam environment at 200 °C with variation of 30%, 40%, and 50% solvothermal volume. Scanning electron micrographs reveals significant increase of porosity on the carbon surface and differences of structural pores between the variations. The results show the possible potential of utilizing low temperature-solvothermal method for nanoporous carbon material.

40 CFR 458.41 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Lamp Process Subcategory... apply to this subpart. (b) The term “product” shall mean carbon black manufactured by the lamp process. ...

40 CFR 458.41 - Specialized definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Lamp Process Subcategory... apply to this subpart. (b) The term “product” shall mean carbon black manufactured by the lamp process. ...

The changing Arctic carbon cycle: using the past to understand terrestrial-aquatic linkages

NASA Astrophysics Data System (ADS)

Anderson, N. J.; van Hardenbroek, M.; Jones, V.; McGowan, S.; Langdon, P. G.; Whiteford, E.; Turner, S.; Edwards, M. E.

2016-12-01

Predicted shifts in terrestrial vegetation cover associated with Arctic warming are altering the delivery and processing of carbon to aquatic ecosystems. This process could determine whether lakes are net carbon sources or sinks and, because lake density is high in many Arctic areas, may alter regional carbon budgets. Lake sediment records integrate information from within the lake and its catchment and can be used quantify past vegetation shifts associated with known climatic episodes of warmer (Holocene Thermal Maximum) and cooler (Neoglacial) conditions. We analysed sediment cores located in different Arctic vegetation biomes (tundra, shrub, forested) in Greenland, Norway and Alaska and used biochemical (algal pigments, stable isotopes) remains to evaluate whether past vegetation shifts were associated with changes in ecosystem carbon processing and biodiversity. When lake catchments were sparsely vegetated and soil vegetation was limited ultra-violet radiation (UVR) screening pigments indicate clear lake waters, scarce dissolved organic carbon/ matter (DOC/M). Moderate vegetation development (birch scrub in Norway; herb tundra in Greenland) appears to enhance delivery of DOM to lakes, and to stimulate algal production which is apparently linked to heterotrophic carbon processing pathways (e.g. algal mixotrophy, nutrient release via the microbial loop). Mature forest cover (in Alaska and Norway) supressed lake autotrophic production, most likely because coloured DOM delivered from catchment vegetation limited light availability. During wetter periods when mires developed lake carbon processing also changed, indicating that hydrological delivery of terrestrial DOM is also important. Therefore, future changes in Arctic vegetation and precipitation patterns are highly likely to alter the way that arctic ecosystems process carbon. Our approach provides an understanding of how ecosystem diversity and carbon processing respond to past climate change and the difficulty of identifying the drivers of state changes in the arctic.

Modeling carbon cycle process of soil profile in Loess Plateau of China

NASA Astrophysics Data System (ADS)

Yu, Y.; Finke, P.; Guo, Z.; Wu, H.

2011-12-01

SoilGen2 is a process-based model, which could reconstruct soil formation under various climate conditions, parent materials, vegetation types, slopes, expositions and time scales. Both organic and inorganic carbon cycle processes could be simulated, while the later process is important in carbon cycle of arid and semi-arid regions but seldom being studied. After calibrating parameters of dust deposition rate and segments depth affecting elements transportation and deposition in the profile, modeling results after 10000 years were confronted with measurements of two soil profiles in loess plateau of China, The simulated trends of organic carbon and CaCO3 in the profile are similar to measured values. Relative sensitivity analysis for carbon cycle process have been done and the results show that the change of organic carbon in long time scale is more sensitive to precipitation, temperature, plant carbon input and decomposition parameters (decomposition rate of humus, ratio of CO2/(BIO+HUM), etc.) in the model. As for the inorganic carbon cycle, precipitation and potential evaporation are important for simulation quality, while the leaching and deposition of CaCO3 are not sensitive to pCO2 and temperature of atmosphere.

Biochar Preparation from Simulated Municipal Solid Waste Employing Low Temperature Carbonization Process

NASA Astrophysics Data System (ADS)

Areeprasert, C.; Leelachaikul, P.; Jangkobpattana, G.; Phumprasop, K.; Kiattiwat, T.

2018-02-01

This paper presents an investigation on carbonization process of simulated municipal solid waste (MSW). Simulated MSW consists of a representative of food residue (68%), plastic waste (20%), paper (8%), and textile (4%). Laboratory-scale carbonization was performed in this study using a vertical-type pyrolyzer varying carbonization temperature (300, 350, 400, and 450 °C) and heating rate (5, 10, 15, and 20 °C/min). Appearance of the biochar product was in black and the volume was significantly reduced. Low carbonization temperature (300 °C) might not completely decompose plastic materials in MSW. Results showed that the carbonization at the temperature of 400 °C with the heating rate of 5 °C/min was the optimal condition. The yield of biochar from the optimal process was 50.6% with the heating value of 26.85 MJ/kg. Energy input of the process was attributed to water evaporation and the decomposition of plastics and paper. Energy output of the process was highest at the optimal condition. Energy output and input ratio was around 1.3-1.7 showing the feasibility of the carbonization process in all heating rate condition.

Size-dependent surface phase change of lithium iron phosphate during carbon coating

NASA Astrophysics Data System (ADS)

Wang, Jiajun; Yang, Jinli; Tang, Yongji; Liu, Jian; Zhang, Yong; Liang, Guoxian; Gauthier, Michel; Karen Chen-Wiegart, Yu-Chen; Norouzi Banis, Mohammad; Li, Xifei; Li, Ruying; Wang, Jun; Sham, T. K.; Sun, Xueliang

2014-03-01

Carbon coating is a simple, effective and common technique for improving the conductivity of active materials in lithium ion batteries. However, carbon coating provides a strong reducing atmosphere and many factors remain unclear concerning the interface nature and underlying interaction mechanism that occurs between carbon and the active materials. Here, we present a size-dependent surface phase change occurring in lithium iron phosphate during the carbon coating process. Intriguingly, nanoscale particles exhibit an extremely high stability during the carbon coating process, whereas microscale particles display a direct visualization of surface phase changes occurring at the interface at elevated temperatures. Our findings provide a comprehensive understanding of the effect of particle size during carbon coating and the interface interaction that occurs on carbon-coated battery material—allowing for further improvement in materials synthesis and manufacturing processes for advanced battery materials.

Gas-solid carbonation as a possible source of carbonates in cold planetary environments

NASA Astrophysics Data System (ADS)

Garenne, A.; Montes-Hernandez, G.; Beck, P.; Schmitt, B.; Brissaud, O.; Pommerol, A.

2013-02-01

Carbonates are abundant sedimentary minerals at the surface and sub-surface of the Earth and they have been proposed as tracers of liquid water in extraterrestrial environments. Their formation mechanism is since generally associated with aqueous alteration processes. Recently, carbonate minerals have been discovered on Mars' surface by different orbitals or rover missions. In particular, the phoenix mission has measured from 1% to 5% of calcium carbonate (calcite type) within the soil (Smith et al., 2009). These occurrences have been reported in area where the relative humidity is significantly high (Boynton et al., 2009). The small concentration of carbonates suggests an alternative process on mineral grain surfaces (as suggested by Shaheen et al., 2010) than carbonation in aqueous conditions. Such an observation could rather point toward a possible formation mechanism by dust-gas reaction under current Martian conditions. To understand the mechanism of carbonate formation under conditions relevant to current Martian atmosphere and surface, we designed an experimental setup consisting of an infrared microscope coupled to a cryogenic reaction cell (IR-CryoCell setup). Three different mineral precursors of carbonates (Ca and Mg hydroxides, and a hydrated Ca silicate formed from Ca2SiO4), low temperature (from -10 to +30 °C), and reduced CO2 pressure (from 100 to 2000 mbar) were utilized to investigate the mechanism of gas-solid carbonation at mineral surfaces. These mineral materials are crucial precursors to form Ca and Mg carbonates in humid environments (0%

Ancient Terrestrial Carbon: Lost and Found

NASA Astrophysics Data System (ADS)

Freeman, K. H.

2017-12-01

Carbon fluxes in terrestrial environments dominate the global carbon cycle. The fluxes of terrestrial carbon are strongly tied to regional climate due to the influences of temperature, water, and nutrient dynamics on plant productivity. However, climate also influences the destruction of terrestrial organic matter, through weathering, erosion, and biomass loss via fire and oxidative microbial processes. Organic geochemical methods enable us to interrogate past terrestrial carbon dynamics and learn how continental processes might accelerate, or mitigate carbon transfer to the atmosphere, and the associated greenhouse warming. Terrestrial soil systems represent the weathering rind of the continents, and are inherently non-depositional and erosive. The production, transport, and depositional processes affecting organics in continental settings each impart their own biases on the amount and characteristics of preserved carbon. Typically, the best archives for biomarker records are sediments in ancient lakes or subaqueous fans, which represents a preservation bias that tends to favor wetter environments. Paleosols, or ancient soils, formed under depositional conditions that, for one reason or another, truncated soil ablation, erosion, or other loss processes. In modern soils, widely ranging organic carbon abundances are almost always substantially greater than the trace amounts of carbon left behind in ancient soils. Even so, measureable amounts of organic biomarkers persist in paleosols. We have been investigating processes that preserve soil organic carbon on geologic timescales, and how these mechanisms may be sensitive to past climate change. Climate-linked changes in temperature, moisture, pH, and weathering processes can impact carbon preservation via organo-mineral sorption, soil biogeochemistry, and stability based on the physical and chemical properties of organic compounds. These will be discussed and illustrated with examples from our studies of Cenozoic terrestrial archives. Mechanistic-based understanding of climate's role in the extensive loss of carbon within both deep and shallow ancient soil horizons has implications for predicting modern carbon budgets on a rapidly warming planet.

Magneto-carbonization method for production of carbon fiber, and high performance carbon fibers made thereby

DOEpatents

Naskar, Amit K.; Ozcan, Soydan; Eberle, Claude C.; Abdallah, Mohamed Gabr; Mackiewicz, Ludtka Gail; Ludtka, Gerard Michael; Paulauskas, Felix Leonard; Rivard, John Daniel Kennedy

2017-08-08

Method for the preparation of carbon fiber from fiber precursor, wherein the fiber precursor is subjected to a magnetic field of at least 3 Tesla during a carbonization process. The carbonization process is generally conducted at a temperature of at least 400.degree. C. and less than 2200.degree. C., wherein, in particular embodiments, the carbonization process includes a low temperature carbonization step conducted at a temperature of at least or above 400.degree. C. or 500.degree. C. and less than or up to 1000.degree. C., 1100.degree. C., or 1200.degree. C., followed by a high temperature carbonization step conducted at a temperature of at least or above 1200.degree. C. In particular embodiments, particularly in the case of a polyacrylonitrile (PAN) fiber precursor, the resulting carbon fiber may possess a minimum tensile strength of at least 600 ksi, a tensile modulus of at least 30 Msi, and an ultimate elongation of at least 1.5%.

The decadal state of the terrestrial carbon cycle: Global retrievals of terrestrial carbon allocation, pools, and residence times

PubMed Central

Bloom, A. Anthony; Exbrayat, Jean-François; van der Velde, Ivar R.; Feng, Liang; Williams, Mathew

2016-01-01

The terrestrial carbon cycle is currently the least constrained component of the global carbon budget. Large uncertainties stem from a poor understanding of plant carbon allocation, stocks, residence times, and carbon use efficiency. Imposing observational constraints on the terrestrial carbon cycle and its processes is, therefore, necessary to better understand its current state and predict its future state. We combine a diagnostic ecosystem carbon model with satellite observations of leaf area and biomass (where and when available) and soil carbon data to retrieve the first global estimates, to our knowledge, of carbon cycle state and process variables at a 1° × 1° resolution; retrieved variables are independent from the plant functional type and steady-state paradigms. Our results reveal global emergent relationships in the spatial distribution of key carbon cycle states and processes. Live biomass and dead organic carbon residence times exhibit contrasting spatial features (r = 0.3). Allocation to structural carbon is highest in the wet tropics (85–88%) in contrast to higher latitudes (73–82%), where allocation shifts toward photosynthetic carbon. Carbon use efficiency is lowest (0.42–0.44) in the wet tropics. We find an emergent global correlation between retrievals of leaf mass per leaf area and leaf lifespan (r = 0.64–0.80) that matches independent trait studies. We show that conventional land cover types cannot adequately describe the spatial variability of key carbon states and processes (multiple correlation median = 0.41). This mismatch has strong implications for the prediction of terrestrial carbon dynamics, which are currently based on globally applied parameters linked to land cover or plant functional types. PMID:26787856

Material processing of oil palm empty fruit bunches for use as raw material of conductive carbon paper

NASA Astrophysics Data System (ADS)

Destyorini, F.; Indayaningsih, N.

2017-04-01

Empty fruit bunches of oil palm is a by-product of the palm oil industry that contains a high element of carbon. This by-product can be processed into a conductive carbon paper that could be applied as fuel cell electrodes. Carbon paper for this application must be conductive, porous, and hydrophobic. Utilization of oil palm empty fruit bunches begins with the carbonization process at a temperature of 500°C that produced charcoal. It is followed by heating at temperature of 900°C and 1300°C. To obtain the carbon paper, powdered charcoal with polymer binder (PEG and EVA) were mixed in solvent and molded using tape casting method. This process successfully produced carbon paper with dimensions of ±(20x20) cm2 and a thickness of 0.1-0.3 mm. Properties of carbon paper were characterized and analyzed in terms of electrical conductivity, porosity, hydrophobic property, and microstructure. Polytetrafluoroethylene (PTFE), a hydrophobic agent, was treated on carbon paper to enhance the hydrophobicity of the carbon paper. PTFE coating on the surface of the carbon paper could change their physical properties. Carbon paper shows excellent properties in terms of porosity and hydrophobicity. Whereas, its electrical property needs to be improved further by increasing the pyrolysis temperature. But overall, this might show a potential GDL material for PEMFC.

A carbon dioxide stripping model for mammalian cell culture in manufacturing scale bioreactors.

PubMed

Xing, Zizhuo; Lewis, Amanda M; Borys, Michael C; Li, Zheng Jian

2017-06-01

Control of carbon dioxide within the optimum range is important in mammalian bioprocesses at the manufacturing scale in order to ensure robust cell growth, high protein yields, and consistent quality attributes. The majority of bioprocess development work is done in laboratory bioreactors, in which carbon dioxide levels are more easily controlled. Some challenges in carbon dioxide control can present themselves when cell culture processes are scaled up, because carbon dioxide accumulation is a common feature due to longer gas-residence time of mammalian cell culture in large scale bioreactors. A carbon dioxide stripping model can be used to better understand and optimize parameters that are critical to cell culture processes at the manufacturing scale. The prevailing carbon dioxide stripping models in literature depend on mass transfer coefficients and were applicable to cell culture processes with low cell density or at stationary/cell death phase. However, it was reported that gas bubbles are saturated with carbon dioxide before leaving the culture, which makes carbon dioxide stripping no longer depend on a mass transfer coefficient in the new generation cell culture processes characterized by longer exponential growth phase, higher peak viable cell densities, and higher specific production rate. Here, we present a new carbon dioxide stripping model for manufacturing scale bioreactors, which is independent of carbon dioxide mass transfer coefficient, but takes into account the gas-residence time and gas CO 2 saturation time. The model was verified by CHO cell culture processes with different peak viable cell densities (7 to 12 × 10 6  cells mL -1 ) for two products in 5,000-L and 25,000-L bioreactors. The model was also applied to a next generation cell culture process to optimize cell culture conditions and reduce carbon dioxide levels at manufacturing scale. The model provides a useful tool to understand and better control cell culture carbon dioxide profiles for process development, scale up, and characterization. Biotechnol. Bioeng. 2017;114: 1184-1194. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Transition metal-catalyzed process for addition of amines to carbon-carbon double bonds

DOEpatents

Hartwig, John F.; Kawatsura, Motoi; Loeber, Oliver

2002-01-01

The present invention is directed to a process for addition of amines to carbon-carbon double bonds in a substrate, comprising: reacting an amine with a compound containing at least one carbon-carbon double bond in the presence a transition metal catalyst under reaction conditions effective to form a product having a covalent bond between the amine and a carbon atom of the former carbon-carbon double bond. The transition metal catalyst comprises a Group 8 metal and a ligand containing one or more 2-electron donor atoms. The present invention is also directed to enantioselective reactions of amine compounds with compounds containing carbon-carbon double bonds, and a calorimetric assay to evaluate potential catalysts in these reactions.

Acoustic and Hydrodynamic Cavitations for Nano CaCO3 Synthesis

NASA Astrophysics Data System (ADS)

Sonawane, Shirish H.; Kulkarni, Ravindra D.

Calcium carbonate is a common inorganic compound known as limestone. Calcium carbonate has many applications in industries such as medicine, agriculture, paint plastic and surface coatings etc. The vast majority of calcium carbonate used in industry is extracted by mining process. Pure calcium carbonate (e.g. for food or pharmaceutical use), is synthesized by passing carbon dioxide into a solution of calcium hydroxide slurry. In this process calcium carbonate precipitates out, and this grade of product is referred to as precipitate calcium carbonate (abbreviated as PCC).

Modeling of the HiPco process for carbon nanotube production. II. Reactor-scale analysis

NASA Technical Reports Server (NTRS)

Gokcen, Tahir; Dateo, Christopher E.; Meyyappan, M.

2002-01-01

The high-pressure carbon monoxide (HiPco) process, developed at Rice University, has been reported to produce single-walled carbon nanotubes from gas-phase reactions of iron carbonyl in carbon monoxide at high pressures (10-100 atm). Computational modeling is used here to develop an understanding of the HiPco process. A detailed kinetic model of the HiPco process that includes of the precursor, decomposition metal cluster formation and growth, and carbon nanotube growth was developed in the previous article (Part I). Decomposition of precursor molecules is necessary to initiate metal cluster formation. The metal clusters serve as catalysts for carbon nanotube growth. The diameter of metal clusters and number of atoms in these clusters are some of the essential information for predicting carbon nanotube formation and growth, which is then modeled by the Boudouard reaction with metal catalysts. Based on the detailed model simulations, a reduced kinetic model was also developed in Part I for use in reactor-scale flowfield calculations. Here this reduced kinetic model is integrated with a two-dimensional axisymmetric reactor flow model to predict reactor performance. Carbon nanotube growth is examined with respect to several process variables (peripheral jet temperature, reactor pressure, and Fe(CO)5 concentration) with the use of the axisymmetric model, and the computed results are compared with existing experimental data. The model yields most of the qualitative trends observed in the experiments and helps to understanding the fundamental processes in HiPco carbon nanotube production.

An important atomic process in the CVD growth of graphene: Sinking and up-floating of carbon atom on copper surface

NASA Astrophysics Data System (ADS)

Li, Yingfeng; Li, Meicheng; Gu, TianSheng; Bai, Fan; Yu, Yue; Trevor, Mwenya; Yu, Yangxin

2013-11-01

By density functional theory (DFT) calculations, the early stages of the growth of graphene on copper (1 1 1) surface are investigated. At the very first time of graphene growth, the carbon atom sinks into subsurface. As more carbon atoms are adsorbed nearby the site, the sunken carbon atom will spontaneously form a dimer with one of the newly adsorbed carbon atoms, and the formed dimer will up-float on the top of the surface. We emphasize the role of the co-operative relaxation of the co-adsorbed carbon atoms in facilitating the sinking and up-floating of carbon atoms. In detail: when two carbon atoms are co-adsorbed, their co-operative relaxation will result in different carbon-copper interactions for the co-adsorbed carbon atoms. This difference facilitates the sinking of a single carbon atom into the subsurface. As a third carbon atom is co-adsorbed nearby, it draws the sunken carbon atom on top of the surface, forming a dimer. Co-operative relaxations of the surface involving all adsorbed carbon atoms and their copper neighbors facilitate these sinking and up-floating processes. This investigation is helpful for the deeper understanding of graphene synthesis and the choosing of optimal carbon sources or process.

Carbon Fiber Reinforced Carbon Composite Valve for an Internal Combustion Engine

NASA Technical Reports Server (NTRS)

Rivers, H. Kevin (Inventor); Ransone, Philip O. (Inventor); Northam, G. Burton (Inventor)

1999-01-01

A carbon fiber reinforced carbon composite valve for internal combustion engines and the like formed of continuous carbon fibers throughout the valve's stem and head is disclosed. The valve includes braided carbon fiber material over axially aligned unidirectional carbon fibers forming a valve stem; the braided and unidirectional carbon fibers being broomed out at one end of the valve stem forming the shape of the valve head; the valve-shaped structure being densified and rigidized with a matrix of carbon containing discontinuous carbon fibers: and the finished valve being treated to resist oxidation. Also disclosed is a carbon matrix plug containing continuous and discontinuous carbon fibers and forming a net-shape valve head acting as a mandrel over which the unidirectional and braided carbon fibers are formed according to textile processes. Also disclosed are various preform valves and processes for making finished and preform carbon fiber reinforced carbon composite valves.

Fabrication and Properties of Carbon Fibers

PubMed Central

Huang, Xiaosong

2009-01-01

This paper reviews the research and development activities conducted over the past few decades on carbon fibers. The two most important precursors in the carbon fiber industry are polyacrylonitrile (PAN) and mesophase pitch (MP). The structure and composition of the precursor affect the properties of the resultant carbon fibers significantly. Although the essential processes for carbon fiber production are similar, different precursors require different processing conditions in order to achieve improved performance. The research efforts on process optimization are discussed in this review. The review also attempts to cover the research on other precursor materials developed mainly for the purpose of cost reduction.

A High-Resolution View of Global Seismicity

NASA Astrophysics Data System (ADS)

Waldhauser, F.; Schaff, D. P.

2014-12-01

We present high-precision earthquake relocation results from our global-scale re-analysis of the combined seismic archives of parametric data for the years 1964 to present from the International Seismological Centre (ISC), the USGS's Earthquake Data Report (EDR), and selected waveform data from IRIS. We employed iterative, multistep relocation procedures that initially correct for large location errors present in standard global earthquake catalogs, followed by a simultaneous inversion of delay times formed from regional and teleseismic arrival times of first and later arriving phases. An efficient multi-scale double-difference (DD) algorithm is used to solve for relative event locations to the precision of a few km or less, while incorporating information on absolute hypocenter locations from catalogs such as EHB and GEM. We run the computations on both a 40-core cluster geared towards HTC problems (data processing) and a 500-core HPC cluster for data inversion. Currently, we are incorporating waveform correlation delay time measurements available for events in selected regions, but are continuously building up a comprehensive, global correlation database for densely distributed events recorded at stations with a long history of high-quality waveforms. The current global DD catalog includes nearly one million earthquakes, equivalent to approximately 70% of the number of events in the ISC/EDR catalogs initially selected for relocation. The relocations sharpen the view of seismicity in most active regions around the world, in particular along subduction zones where event density is high, but also along mid-ocean ridges where existing hypocenters are especially poorly located. The new data offers the opportunity to investigate earthquake processes and fault structures along entire plate boundaries at the ~km scale, and provides a common framework that facilitates analysis and comparisons of findings across different plate boundary systems.

40 CFR 458.20 - Applicability: description of the carbon black thermal process subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 31 2013-07-01 2013-07-01 false Applicability: description of the carbon black thermal process subcategory. 458.20 Section 458.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Thermal...

40 CFR 458.10 - Applicability; description of the carbon black furnace process subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Applicability; description of the carbon black furnace process subcategory. 458.10 Section 458.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Furnace...

40 CFR 458.30 - Applicability; description of the carbon black channel process subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Applicability; description of the carbon black channel process subcategory. 458.30 Section 458.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Channel...

40 CFR 458.10 - Applicability; description of the carbon black furnace process subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 31 2013-07-01 2013-07-01 false Applicability; description of the carbon black furnace process subcategory. 458.10 Section 458.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Furnace...

40 CFR 458.20 - Applicability: description of the carbon black thermal process subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Applicability: description of the carbon black thermal process subcategory. 458.20 Section 458.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Thermal...

40 CFR 458.30 - Applicability; description of the carbon black channel process subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 31 2013-07-01 2013-07-01 false Applicability; description of the carbon black channel process subcategory. 458.30 Section 458.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Channel...

Process for sequestering carbon dioxide and sulfur dioxide

DOEpatents

Maroto-Valer, M Mercedes [State College, PA; Zhang, Yinzhi [State College, PA; Kuchta, Matthew E [State College, PA; Andresen, John M [State College, PA; Fauth, Dan J [Pittsburgh, PA

2009-10-20

A process for sequestering carbon dioxide, which includes reacting a silicate based material with an acid to form a suspension, and combining the suspension with carbon dioxide to create active carbonation of the silicate-based material, and thereafter producing a metal salt, silica and regenerating the acid in the liquid phase of the suspension.

Process to minimize cracking of pyrolytic carbon coatings

DOEpatents

Lackey, Jr., Walter J.; Sease, John D.

1978-01-01

Carbon-coated microspheroids useful as fuels in nuclear reactors are produced with a low percentage of cracked coatings and are imparted increased strength and mechanical stability characteristics by annealing immediately after the carbon coating processes.

Formation of Carbon Nanotubes in a Microgravity Environment

NASA Technical Reports Server (NTRS)

Alford, J. M.; Mason, G. R.; Feikema, D. A.

2001-01-01

Even though nanotube science has become one of the worlds most rapidly advancing areas of research, very little is known about the processes involved in nanotube synthesis. To study the formation of carbon nanotubes in an environment unhindered by the buoyancy induced flows generated by the high temperatures necessary to vaporize carbon and grow nanotubes, we have designed a miniature carbon arc apparatus that can produce carbon nanotubes under microgravity conditions. During the first phase of this project, we designed, built, and successfully tested the mini carbon arc in both 1g and 2.2 sec drop tower microgravity conditions. We have demonstrated that microgravity can eliminate the strong convective flows from the carbon arc and we have successfully produced single-walled carbon nanotubes in microgravity. We believe that microgravity processing will allow us to better understand the nanotube formation process and eventually allow us to grow nanotubes that are superior to ground-based production.

DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

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

Elliot B. Kennel; Chong Chen; Dady Dadyburjor

2005-04-13

The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. These carbon products include materials used in metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. Table 1 provides an overview of the major markets for carbon products. Current sources of materials for these processes generally rely on petroleum distillation products or coal tar distillates obtained as a byproduct of metcoke production facilities. In the former case, the American materials industry, just asmore » the energy industry, is dependent upon foreign sources of petroleum. In the latter case, metcoke production is decreasing every year due to the combined difficulties associated with poor economics and a significant environmental burden. Thus, a significant need exists for an environmentally clean process which can used domestically obtained raw materials and which can still be very competitive economically.« less

Chemical activation of gasification carbon residue for phosphate removal

NASA Astrophysics Data System (ADS)

Kilpimaa, Sari; Runtti, Hanna; Lassi, Ulla; Kuokkanen, Toivo

2012-05-01

Recycling of waste materials provides an economical and environmentally significant method to reduce the amount of waste. Bioash formed in the gasification process possesses a notable amount of unburned carbon and therefore it can be called a carbon residue. After chemical activation carbon residue could be use to replace activated carbon for example in wastewater purification processes. The effect of chemical activation process variables such as chemical agents and contact time in the chemical activation process were investigated. This study also explored the effectiveness of the chemically activated carbon residue for the removal of phosphate from an aqueous solution. The experimental adsorption study was performed in a batch reactor and the influence of adsorption time, initial phosphate concentration and pH was studied. Due to the carbon residue's low cost and high adsorption capacity, this type of waste has the potential to be utilised for the cost-effective removal of phosphate from wastewaters. Potential adsorbents could be prepared from these carbonaceous by-products and used as an adsorbent for phosphate removal.

[Dynamics of unprotected soil organic carbon with the restoration process of Pinus massoniana plantation in red soil erosion area].

PubMed

Lü, Mao-Kui; Xie, Jin-Sheng; Zhou, Yan-Xiang; Zeng, Hong-Da; Jiang, Jun; Chen, Xi-Xiang; Xu, Chao; Chen, Tan; Fu, Lin-Chi

2014-01-01

By the method of spatiotemporal substitution and taking the bare land and secondary forest as the control, we measured light fraction and particulate organic carbon in the topsoil under the Pinus massoniana woodlands of different ages with similar management histories in a red soil erosion area, to determine their dynamics and evaluate the conversion processes from unprotected to protected organic carbon. The results showed that the content and storage of soil organic carbon increased significantly along with ages in the process of vegetation restoration (P < 0.01). The unprotected soil organic carbon content and distribution proportion to the total soil organic carbon increased significantly (P < 0.05) after 7-11 years' restoration but stabilized after 27 and 30 years of restoration. It suggested that soil organic carbon mostly accumulated in the form of unprotected soil organic carbon during the initial restoration period, and reached a stable level after long-term vegetation restoration. Positive correlations were found between restoration years and the rate constant for C transferring from the unprotected to the protected soil pool (k) in 0-10 cm and 10-20 cm soil layers, which demonstrated that the unprotected soil organic carbon gradually transferred to the protected soil organic carbon in the process of vegetation restoration.

Environmental Benefit Assessment for the Carbonation Process of Petroleum Coke Fly Ash in a Rotating Packed Bed.

PubMed

Pei, Si-Lu; Pan, Shu-Yuan; Li, Ye-Mei; Chiang, Pen-Chi

2017-09-19

A high-gravity carbonation process was deployed at a petrochemical plant using petroleum coke fly ash and blowdown wastewater to simultaneously mineralized CO 2 and remove nitrogen oxides and particulate matters from the flue gas. With a high-gravity carbonation process, the CO 2 removal efficiency was found to be 95.6%, corresponding to a capture capacity of 600 kg CO 2 per day, at a gas flow rate of 1.47 m 3 /min under ambient temperature and pressure. Moreover, the removal efficiency of nitrogen oxides and particulate matters was 99.1% and 83.2%, respectively. After carbonation, the reacted fly ash was further utilized as supplementary cementitious materials in the blended cement mortar. The results indicated that cement with carbonated fly ash exhibited superior compressive strength (38.1 ± 2.5 MPa at 28 days in 5% substitution ratio) compared to the cement with fresh fly ash. Furthermore, the environmental benefits for the high-gravity carbonation process using fly ash were critically assessed. The energy consumption of the entire high-gravity carbonation ranged from 80 to 169 kWh/t-CO 2 (0.29-0.61 GJ/t-CO 2 ). Compared with the scenarios of business-as-usual and conventional carbon capture and storage plant, the economic benefit from the high-gravity carbonation process was approximately 90 and 74 USD per ton of CO 2 fixation, respectively.

Weathering controls on mechanisms of carbon storage in grassland soils

USGS Publications Warehouse

Masiello, C.A.; Chadwick, O.A.; Southon, J.; Torn, M.S.; Harden, J.W.

2004-01-01

On a sequence of soils developed under similar vegetation, temperature, and precipitation conditions, but with variations in mineralogical properties, we use organic carbon and 14C inventories to examine mineral protection of soil organic carbon. In these soils, 14C data indicate that the creation of slow-cycling carbon can be modeled as occurring through reaction of organic ligands with Al3+ and Fe3+ cations in the upper horizons, followed by sorption to amorphous inorganic Al compounds at depth. Only one of these processes, the chelation Al3+ and Fe3+ by organic ligands, is linked to large carbon stocks. Organic ligands stabilized by this process traverse the soil column as dissolved organic carbon (both from surface horizons and root exudates). At our moist grassland site, this chelation and transport process is very strongly correlated with the storage and long-term stabilization of soil organic carbon. Our 14C results show that the mechanisms of organic carbon transport and storage at this site follow a classic model previously believed to only be significant in a single soil order (Spodosols), and closely related to the presence of forests. The presence of this process in the grassland Alfisol, Inceptisol, and Mollisol soils of this chronosequence suggests that this process is a more significant control on organic carbon storage than previously thought. Copyright 2004 by the American Geophysical Union.

Investigation of Conditions of Titanium Carbonization - IV

NASA Technical Reports Server (NTRS)

Meerson, G. A.; Lipkes, Y. M.

1949-01-01

In a previous paper, results are presented of accurate investigations of the processes of titanium carbonization and the succeeding titanium carbide decarbonization as related to the phenomenon of the graphitization of soot by heating at a constant temperature in atmospheres of pure hydrogen and carbon monoxide. These tests showed that the processes of titanium carbonization-decarbonization in an atmosphere of pure gases without nitrogen proceed in the same direction as the analogous processes under the conditions of the production furnace. In this case, however, the presence of admixtures of nitrogen changes the quantitative results of the decarbonization process. Thermodynamic computations confirming the results of previous tests conducted at atmospheric pressure and additional tests of titanium carbonization at lowered pressures are presented herein.

Membrane loop process for separating carbon dioxide for use in gaseous form from flue gas

DOEpatents

Wijmans, Johannes G; Baker, Richard W; Merkel, Timothy C

2014-10-07

The invention is a process involving membrane-based gas separation for separating and recovering carbon dioxide emissions from combustion processes in partially concentrated form, and then transporting the carbon dioxide and using or storing it in a confined manner without concentrating it to high purity. The process of the invention involves building up the concentration of carbon dioxide in a gas flow loop between the combustion step and a membrane separation step. A portion of the carbon dioxide-enriched gas can then be withdrawn from this loop and transported, without the need to liquefy the gas or otherwise create a high-purity stream, to a destination where it is used or confined, preferably in an environmentally benign manner.

Optimized heat exchange in a CO2 de-sublimation process

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

Baxter, Larry; Terrien, Paul; Tessier, Pascal

The present invention is a process for removing carbon dioxide from a compressed gas stream including cooling the compressed gas in a first heat exchanger, introducing the cooled gas into a de-sublimating heat exchanger, thereby producing a first solid carbon dioxide stream and a first carbon dioxide poor gas stream, expanding the carbon dioxide poor gas stream, thereby producing a second solid carbon dioxide stream and a second carbon dioxide poor gas stream, combining the first solid carbon dioxide stream and the second solid carbon dioxide stream, thereby producing a combined solid carbon dioxide stream, and indirectly exchanging heat betweenmore » the combined solid carbon dioxide stream and the compressed gas in the first heat exchanger.« less

Fermentation process for the production of organic acids

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

Hermann, Theron; Reinhardt, James; Yu, Xiaohui

This invention relates to improvements in the fermentation process used in the production of organic acids from biological feedstock using bacterial catalysts. The improvements in the fermentation process involve providing a fermentation medium comprising an appropriate form of inorganic carbon, an appropriate amount of aeration and a biocatalyst with an enhanced ability to uptake and assimilate the inorganic carbon into the organic acids. This invention also provides, as a part of an integrated fermentation facility, a novel process for producing a solid source of inorganic carbon by sequestering carbon released from the fermentation in an alkali solution.

Controlling porosity in lignin-derived nanoporous carbon for supercapacitor applications

DOE PAGES

Jeon, Ju-Won; Zhang, Libing; Lutkenhaus, Jodie L.; ...

2015-02-01

Low-cost renewable lignin has been used as a precursor to produce porous carbons. However, to date, it has not been easy to obtain high surface area porous carbon without activation processes or templating agents. Here, we demonstrate that low molecular weight lignin yields highly porous carbon (1092 m² g⁻¹) with more graphitization through direct carbonization without additional activation processes or templating agents. We found that molecular weight and oxygen consumption during carbonization are critical factors to obtain high surface area, graphitized porous carbons. This highly porous carbon from low-cost renewable lignin sources is a good candidate for supercapacitor electrode materials.

Controlling porosity in lignin-derived nanoporous carbon for supercapacitor applications

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

Jeon, Ju-Won; Zhang, Libing; Lutkenhaus, Jodie L.

Low-cost renewable lignin has been used as a precursor to produce porous carbons. However, to date, it has not been easy to obtain high surface area porous carbon without activation processes or templating agents. Here, we demonstrate that low molecular weight lignin yields highly porous carbon (1092 m² g⁻¹) with more graphitization through direct carbonization without additional activation processes or templating agents. We found that molecular weight and oxygen consumption during carbonization are critical factors to obtain high surface area, graphitized porous carbons. This highly porous carbon from low-cost renewable lignin sources is a good candidate for supercapacitor electrode materials.

Carbon limitation patterns in buried and open urban streams

EPA Science Inventory

Urban streams alternate between darkened buried segments dominated by heterotrophic processes and lighted open segments dominated by autotrophic processes. We hypothesized that labile carbon leaking from autotrophic cells would reduce heterotrophic carbon limitation in open chan...

The Effects of Different External Carbon Sources on Nitrous Oxide Emissions during Denitrification in Biological Nutrient Removal Processes

NASA Astrophysics Data System (ADS)

Hu, Xiang; Zhang, Jing; Hou, Hongxun

2018-01-01

The aim of this study was to investigate the effects of two different external carbon sources (acetate and ethanol) on the nitrous oxide (N2O) emissions during denitrification in biological nutrient removal processes. Results showed that external carbon source significantly influenced N2O emissions during the denitrification process. When acetate served as the external carbon source, 0.49 mg N/L and 0.85 mg N/L of N2O was produced during the denitrificaiton processes in anoxic and anaerobic/anoxic experiments, giving a ratio of N2O-N production to TN removal of 2.37% and 4.96%, respectively. Compared with acetate, the amount of N2O production is negligible when ethanol used as external carbon addition. This suggested that ethanol is a potential alternative external carbon source for acetate from the point of view of N2O emissions.

Preparation of activated carbon from waste plastics polyethylene terephthalate as adsorbent in natural gas storage

NASA Astrophysics Data System (ADS)

Yuliusman; Nasruddin; Sanal, A.; Bernama, A.; Haris, F.; Ramadhan, I. T.

2017-02-01

The main problem is the process of natural gas storage and distribution, because in normal conditions of natural gas in the gas phase causes the storage capacity be small and efficient to use. The technology is commonly used Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG). The weakness of this technology safety level is low because the requirement for high-pressure CNG (250 bar) and LNG requires a low temperature (-161°C). It takes innovation in the storage of natural gas using the technology ANG (Adsorbed Natural Gas) with activated carbon as an adsorbent, causing natural gas can be stored in a low pressure of about 34.5. In this research, preparation of activated carbon using waste plastic polyethylene terephthalate (PET). PET plastic waste is a good raw material for making activated carbon because of its availability and the price is a lot cheaper. Besides plastic PET has the appropriate characteristics as activated carbon raw material required for the storage of natural gas because the material is hard and has a high carbon content of about 62.5% wt. The process of making activated carbon done is carbonized at a temperature of 400 ° C and physical activation using CO2 gas at a temperature of 975 ° C. The parameters varied in the activation process is the flow rate of carbon dioxide and activation time. The results obtained in the carbonization process yield of 21.47%, while the yield on the activation process by 62%. At the optimum process conditions, the CO2 flow rate of 200 ml/min and the activation time of 240 minutes, the value % burn off amounted to 86.69% and a surface area of 1591.72 m2/g.

Source-sink-storage relationships of conifers

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

Luxmoore, R.J.; Oren, R.; Sheriff, D.W.

1995-07-01

Irradiance, air temperature, saturation vapor pressure deficit, and soil temperature vary in association with Earth`s daily rotation, inducing significant hourly changes in the rates of plant physiological processes. These processes include carbon fixation in photosynthesis, sucrose translocation, and carbon utilization in growth, storage, and respiration. The sensitivity of these physiological processes to environmental factors such as temperature, soil water availability, and nutrient supply reveals differences that must be viewed as an interactive whole in order to comprehend whole-plant responses to the environment. Integrative frameworks for relationships between plant physiological processes are needed to provide syntheses of plant growth and development.more » Source-sink-storage relationships, addressed in this chapter, provide one framework for synthesis of whole-plant responses to external environmental variables. To address this issue, some examples of carbon assimilation and utilization responses of five conifer species to environmental factors from a range of field environments are first summarized. Next, the interactions between sources, sinks, and storages of carbon are examined at the leaf and tree scales, and finally, the review evaluates the proposition that processes involved with carbon utilization (sink activity) are more sensitive to the supply of water and nutrients (particularly nitrogen) than are the processes of carbon gain (source activity) and carbon storage. The terms {open_quotes}sink{close_quotes} and {open_quotes}source{close_quotes} refer to carbon utilization and carbon gain, respectively. The relative roles of stored carbon reserves and of current photosynthate in meeting sink demand are addressed. Discussions focus on source-sink-storage relationships within the diurnal, wetting-drying, and annual cycles of conifer growth and development, and some discussion of life cycle aspects is also presented.« less

Mineral Carbonation Potential of CO2 from Natural and Industrial-based Alkalinity Sources

NASA Astrophysics Data System (ADS)

Wilcox, J.; Kirchofer, A.

2014-12-01

Mineral carbonation is a Carbon Capture and Storage (CSS) technology where gaseous CO2 is reacted with alkaline materials (such as silicate minerals and alkaline industrial wastes) and converted into stable and environmentally benign carbonate minerals (Metz et al., 2005). Here, we present a holistic, transparent life cycle assessment model of aqueous mineral carbonation built using a hybrid process model and economic input-output life cycle assessment approach. We compared the energy efficiency and the net CO2 storage potential of various mineral carbonation processes based on different feedstock material and process schemes on a consistent basis by determining the energy and material balance of each implementation (Kirchofer et al., 2011). In particular, we evaluated the net CO2 storage potential of aqueous mineral carbonation for serpentine, olivine, cement kiln dust, fly ash, and steel slag across a range of reaction conditions and process parameters. A preliminary systematic investigation of the tradeoffs inherent in mineral carbonation processes was conducted and guidelines for the optimization of the life-cycle energy efficiency are provided. The life-cycle assessment of aqueous mineral carbonation suggests that a variety of alkalinity sources and process configurations are capable of net CO2 reductions. The maximum carbonation efficiency, defined as mass percent of CO2 mitigated per CO2 input, was 83% for CKD at ambient temperature and pressure conditions. In order of decreasing efficiency, the maximum carbonation efficiencies for the other alkalinity sources investigated were: olivine, 66%; SS, 64%; FA, 36%; and serpentine, 13%. For natural alkalinity sources, availability is estimated based on U.S. production rates of a) lime (18 Mt/yr) or b) sand and gravel (760 Mt/yr) (USGS, 2011). The low estimate assumes the maximum sequestration efficiency of the alkalinity source obtained in the current work and the high estimate assumes a sequestration efficiency of 85%. The total CO2 storage potential for the alkalinity sources considered in the U.S. ranges from 1.3% to 23.7% of U.S. CO2 emissions, depending on the assumed availability of natural alkalinity sources and efficiency of the mineral carbonation processes.

Composite carbon foam electrode

DOEpatents

Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

1997-01-01

Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivty and power to system energy.

Cyclic process for producing methane from carbon monoxide with heat removal

DOEpatents

Frost, Albert C.; Yang, Chang-lee

1982-01-01

Carbon monoxide-containing gas streams are converted to methane by a cyclic, essentially two-step process in which said carbon monoxide is disproportionated to form carbon dioxide and active surface carbon deposited on the surface of a catalyst, and said carbon is reacted with steam to form product methane and by-product carbon dioxide. The exothermic heat of reaction generated in each step is effectively removed during each complete cycle so as to avoid a build up of heat from cycle-to-cycle, with particularly advantageous techniques being employed for fixed bed, tubular and fluidized bed reactor operations.

Designing and Demonstrating a Master Student Project to Explore Carbon Dioxide Capture Technology

ERIC Educational Resources Information Center

Asherman, Florine; Cabot, Gilles; Crua, Cyril; Estel, Lionel; Gagnepain, Charlotte; Lecerf, Thibault; Ledoux, Alain; Leveneur, Sebastien; Lucereau, Marie; Maucorps, Sarah; Ragot, Melanie; Syrykh, Julie; Vige, Manon

2016-01-01

The rise in carbon dioxide (CO[subscript 2]) concentration in the Earth's atmosphere, and the associated strengthening of the greenhouse effect, requires the development of low carbon technologies. New carbon capture processes are being developed to remove CO[subscript 2] that would otherwise be emitted from industrial processes and fossil fuel…

College Students' Understanding of the Carbon Cycle: Contrasting Principle-Based and Informal Reasoning

ERIC Educational Resources Information Center

Hartley, Laurel M.; Wilke, Brook J.; Schramm, Jonathon W.; D'Avanzo, Charlene; Anderson, Charles W.

2011-01-01

Processes that transform carbon (e.g., photosynthesis) play a prominent role in college biology courses. Our goals were to learn about student reasoning related to these processes and provide faculty with tools for instruction and assessment. We created a framework illustrating how carbon-transforming processes can be related to one another during…

Modified Facile Synthesis for Quantitatively Fluorescent Carbon Dots.

PubMed

Hou, Xiaofang; Hu, Yin; Wang, Ping; Yang, Liju; Al Awak, Mohamad M; Tang, Yongan; Twara, Fridah K; Qian, Haijun; Sun, Ya-Ping

2017-10-01

A simple yet consequential modification was made to the popular carbonization processing of citric acid - polyethylenimine precursor mixtures to produce carbon dots (CDots). The modification was primarily on pushing the carbonization processing a little harder at a higher temperature, such as the hydrothermal processing condition of around 330 °C for 6 hours. The CDots thus produced are comparable in spectroscopic and other properties to those obtained in other more controlled syntheses including the deliberate chemical functionalization of preprocessed and selected small carbon nanoparticles, demonstrating the consistency in CDots and reaffirming their general definition as carbon nanoparticles with surface passivation by organic or other species. Equally significant is the finding that the modified processing of citric acid - polyethylenimine precursor mixtures could yield CDots of record-setting fluorescence performance, approaching the upper limit of being quantitatively fluorescent. Thus, the reported work serves as a demonstration on not only the need in selecting the right processing conditions and its associated opportunities in one-pot syntheses of CDots, but also the feasibility in pursuing the preparation of quantitatively fluorescent CDots, which represents an important milestone in the development and understanding of these fluorescent carbon nanomaterials.

Remediation of nitrate-contaminated groundwater by PRB-Electrokinetic integrated process.

PubMed

Ghaeminia, Mahdyar; Mokhtarani, Nader

2018-05-30

Activated carbon is used as a reactive media in Permeable Reactive Barrier (PRB) for the removal of inorganic contaminants such as nitrate from groundwater. Since removal rate by this media decreases by time and due to the high costs of excavation and replacement of new media, the usage of activated carbon as an adsorbent in PRB is limited. The present study aimed to solve this defect by integrating electrokinetic process and PRB, using in-situ regeneration of activated carbon. This research was carried out on a laboratory scale using synthetically contaminated water and modified activated carbon as a reactive media in PRB. The effects of pH, nitrate concentration, carbon to sand ratio, and also electric gradient on the performance of the process were evaluated, and optimal conditions were determined, to increase the system longevity. According to the results, by applying an electric gradient of 1.25 V cm -1 to the PRB alone process in optimum operating condition (135 mg L -1 initial nitrate concentration, flow rate of 2.3 L min -1 , pH = 6.8, and carbon to sand ratios of 1:1) the adsorbent capacity increased by 90%. Under these conditions, the integrated process could keep nitrate concentration in the effluent below the standard limit for about 111 h, while the PRB alone process could do the same job for about 59 h. Also, SEM analysis showed that by applying electrokinetic process, activated carbon was regenerated. Integration of electrokinetic process and PRB was also caused nitrate to transfer from activated carbon media into the soil layer above the system. This nitrate-rich soil has the potential for reuse in agricultural activities. Copyright © 2018 Elsevier Ltd. All rights reserved.

Optimization evaluation of cutting technology based on mechanical parts

NASA Astrophysics Data System (ADS)

Wang, Yu

2018-04-01

The relationship between the mechanical manufacturing process and the carbon emission is studied on the basis of the process of the mechanical manufacturing process. The formula of carbon emission calculation suitable for mechanical manufacturing process is derived. Based on this, a green evaluation method for cold machining process of mechanical parts is proposed. The application verification and data analysis of the proposed evaluation method are carried out by an example. The results show that there is a great relationship between the mechanical manufacturing process data and carbon emissions.

High Temporal Resolution Characterization of the Carbonate Chemistry and the Relative Influence of Community Metabolic Processes on Controlling Coral Reef Dynamics at La Parguera, Puerto Rico

NASA Astrophysics Data System (ADS)

Melendez, M.; Salisbury, J.; Gledhill, D. K.; Musielewicz, S.; Morell, J. M.; Manzello, D.

2016-02-01

Diverse metabolic processes in conjunction with thermodynamic, physical and benthic related processes modulate seawater carbonate chemistry in near-shore environments. Such processes operate at different time scales. In the open ocean, dynamics and trends in carbonate chemistry are reasonably well constrained and often characterized based on TA-salinity and pCO2-temperature relationships. However, in near-shore environments benthic and coastal processes can convolute these relationships and careful direct measurement of the carbonate system (e.g. through alkalinity and dissolved inorganic carbon) is needed. To this end, we characterized seasonal and inter-annual carbonate dynamics from 2009 to 2014 at the Class III fixed climate station of La Parguera Marine Reserve, Puerto Rico. This high-temporal resolution chemical monitoring at Enrique reef facilitated an examination of what local processes might prove dominant, and how changes in community-scale metabolic performance might alter the dynamics of the carbonate system within the near-shore reef waters. Changes in pCO2,sw at Enrique reef are strongly associated with both community inorganic and organic carbon production processes. Enrique reef is a persistent source of CO2 to the atmosphere (1.8 mmol CO2 m-2 d-1, SE = 0.04) with at maximum peak during the summer and fall seasons. During the same time, carbonate mineral saturation state are generally lower along the fore-reef relative to offshore waters and dominantly controlled by short-term pCO2,sw dynamics primarily driven by benthic community organic matter productivity, temperature and salinity seasonal changes. At this time, high temperatures coincide with intense local rainfall and the influx of the low-salinity Amazon and Orinoco River plumes into the eastern Caribbean. One benefit of such measurements is that they provide data for a more accurate determination of TA-salinity relationships for our region and site-specific algorithms for first order derivations of other carbonate system parameters.

Improved Method of Purifying Carbon Nanotubes

NASA Technical Reports Server (NTRS)

Delzeit, Lance D.

2004-01-01

An improved method of removing the residues of fabrication from carbon nanotubes has been invented. These residues comprise amorphous carbon and metal particles that are produced during the growth process. Prior methods of removing the residues include a variety of processes that involved the use of halogens, oxygen, or air in both thermal and plasma processes. Each of the prior methods entails one or more disadvantages, including non-selectivity (removal or damage of nanotubes in addition to removal of the residues), the need to dispose of toxic wastes, and/or processing times as long as 24 hours or more. In contrast, the process described here does not include the use of toxic chemicals, the generation of toxic wastes, causes little or no damage to the carbon nanotubes, and involves processing times of less than 1 hour. In the improved method, purification is accomplished by flowing water vapor through the reaction chamber at elevated temperatures and ambient pressures. The impurities are converted to gaseous waste products by the selective hydrogenation and hydroxylation by the water in a reaction chamber. This process could be performed either immediately after growth or in a post-growth purification process. The water used needs to be substantially free of oxygen and can be obtained by a repeated freeze-pump-thaw process. The presence of oxygen will non-selectively attach the carbon nanotubes in addition to the amorphous carbon.

Carbon black dispersion pre-plating technology for printed wire board manufacturing. Final technology evaluation report

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

Folsom, D.W.; Gavaskar, A.R.; Jones, J.A.

1993-10-01

The project compared chemical use, waste generation, cost, and product quality between electroless copper and carbon-black-based preplating technologies at the printed wire board (PWB) manufacturing facility of McCurdy Circuits in Orange, CA. The carbon-black based preplating technology evaluated is used as an alternative process for electroless copper (EC) plating of through-holes before electrolytic copper plating. The specific process used at McCurdy is the BlackHole (BH) technology process, which uses a dispersion of carbon black in an aqueous solution to provide a conductive surface for subsequent electrolytic copper plating. The carbon-black dispersion technology provided effective waste reduction and long-term cost savings.more » The economic analysis determined that the new process was cost efficient because chemical use was reduced and the process proved more efficient; the payback period was less than 4 yrs.« less

Carbon-Carbon Turbocharger Housing Unit for Intermittent Combustion Engines

NASA Technical Reports Server (NTRS)

Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

1998-01-01

An improved, lightweight, turbine housing unit for an intermittent combustion reciprocating internal combustion engine turbocharger is prepared from a lay-up or molding of carbon-carbon composite materials in a single-piece or two-piece process. When compared to conventional steel or cast iron, the use of carbon-carbon composite materials in a turbine housing unit reduces the overall weight of the engine and reduces the heat energy loss used in the turbocharging process. This reduction in heat energy loss and weight reduction provides for more efficient engine operation.

Provenance for Runtime Workflow Steering and Validation in Computational Seismology

NASA Astrophysics Data System (ADS)

Spinuso, A.; Krischer, L.; Krause, A.; Filgueira, R.; Magnoni, F.; Muraleedharan, V.; David, M.

2014-12-01

Provenance systems may be offered by modern workflow engines to collect metadata about the data transformations at runtime. If combined with effective visualisation and monitoring interfaces, these provenance recordings can speed up the validation process of an experiment, suggesting interactive or automated interventions with immediate effects on the lifecycle of a workflow run. For instance, in the field of computational seismology, if we consider research applications performing long lasting cross correlation analysis and high resolution simulations, the immediate notification of logical errors and the rapid access to intermediate results, can produce reactions which foster a more efficient progress of the research. These applications are often executed in secured and sophisticated HPC and HTC infrastructures, highlighting the need for a comprehensive framework that facilitates the extraction of fine grained provenance and the development of provenance aware components, leveraging the scalability characteristics of the adopted workflow engines, whose enactment can be mapped to different technologies (MPI, Storm clusters, etc). This work looks at the adoption of W3C-PROV concepts and data model within a user driven processing and validation framework for seismic data, supporting also computational and data management steering. Validation needs to balance automation with user intervention, considering the scientist as part of the archiving process. Therefore, the provenance data is enriched with community-specific metadata vocabularies and control messages, making an experiment reproducible and its description consistent with the community understandings. Moreover, it can contain user defined terms and annotations. The current implementation of the system is supported by the EU-Funded VERCE (http://verce.eu). It provides, as well as the provenance generation mechanisms, a prototypal browser-based user interface and a web API built on top of a NoSQL storage technology, experimenting ways to ensure a rapid and flexible access to the lineage traces. It supports the users with the visualisation of graphical products and offers combined operations to access and download the data which may be selectively stored at runtime, into dedicated data archives.

Carbon Dioxide Reduction Systems

NASA Technical Reports Server (NTRS)

Burghardt, Stanley I.; Chandler, Horace W.; Taylor, T. I.; Walden, George

1961-01-01

The Methoxy system for regenerating oxygen from carbon dioxide was studied. Experiments indicate that the reaction between carbon dioxide and hydrogen can be carried out with ease in an efficient manner and with excellent heat conservation. A small reactor capable of handling the C02 expired by three men has been built and operated. The decomposition of methane by therma1,arc and catalytic processes was studied. Both the arc and catalytic processes gave encouraging results with over 90 percent of the methane being decomposed to carbon and hydrogen in some of the catalytic processes. Control of the carbon deposition in both the catalytic and arc processes is of great importance to prevent catalyst deactivation and short circuiting of electrical equipment. Sensitive analytical techniques have been developed for all of the components present in the reactor effluent streams.

Membrane loop process for separating carbon dioxide for use in gaseous form from flue gas

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

Wijmans, Johannes G; Baker, Richard W; Merkel, Timothy C

The invention is a process involving membrane-based gas separation for separating and recovering carbon dioxide emissions from combustion processes in partially concentrated form, and then transporting the carbon dioxide and using or storing it in a confined manner without concentrating it to high purity. The process of the invention involves building up the concentration of carbon dioxide in a gas flow loop between the combustion step and a membrane separation step. A portion of the carbon dioxide-enriched gas can then be withdrawn from this loop and transported, without the need to liquefy the gas or otherwise create a high-purity stream,more » to a destination where it is used or confined, preferably in an environmentally benign manner.« less

Device for staged carbon monoxide oxidation

DOEpatents

Vanderborgh, Nicholas E.; Nguyen, Trung V.; Guante, Jr., Joseph

1993-01-01

A method and apparatus for selectively oxidizing carbon monoxide in a hydrogen rich feed stream. The method comprises mixing a feed stream consisting essentially of hydrogen, carbon dioxide, water and carbon monoxide with a first predetermined quantity of oxygen (air). The temperature of the mixed feed/oxygen stream is adjusted in a first the heat exchanger assembly (20) to a first temperature. The mixed feed/oxygen stream is sent to reaction chambers (30,32) having an oxidation catalyst contained therein. The carbon monoxide of the feed stream preferentially absorbs on the catalyst at the first temperature to react with the oxygen in the chambers (30,32) with minimal simultaneous reaction of the hydrogen to form an intermediate hydrogen rich process stream having a lower carbon monoxide content than the feed stream. The elevated outlet temperature of the process stream is carefully controlled in a second heat exchanger assembly (42) to a second temperature above the first temperature. The process stream is then mixed with a second predetermined quantity of oxygen (air). The carbon monoxide of the process stream preferentially reacts with the second quantity of oxygen in a second stage reaction chamber (56) with minimal simultaneous reaction of the hydrogen in the process stream. The reaction produces a hydrogen rich product stream having a lower carbon monoxide content than the process stream. The product stream is then cooled in a third heat exchanger assembly (72) to a third predetermined temperature. Three or more stages may be desirable, each with metered oxygen injection.

Microstructure and mechanical properties of nickel coated multi walled carbon nanotube reinforced stainless steel 316L matrix composites by laser sintering process

NASA Astrophysics Data System (ADS)

Mahanthesha, P.; Mohankumar, G. C.

2018-04-01

Electroless Ni coated Multi-walled Carbon nanotubes reinforced with Stainless Steel 316L matrix composite was developed by Direct Metal Laser Sintering process (DMLS). Homogeneous mixture of Stainless Steel 316L powder and carbon nanotubes in different vol. % was obtained by using double cone blender machine. Characterization of electroless Ni coated carbon nanotubes was done by using X-ray diffraction, FESEM and EDS. Test samples were fabricated at different laser scan speeds. Effect of process parameters and CNT vol. % content on solidification microstructure and mechanical properties of test samples was investigated by using Optical microscopy, FESEM, and Hounsfield tensometer. Experimental results reveal DMLS process parameters affect the density and microstructure of sintered parts. Dense parts with minimum porosity when processed at low laser scan speeds and low CNT vol. %. Tensile fractured surface of test specimens evidences the survival of carbon nanotubes under high temperature processing condition.

Atomic scale observation of oxygen delivery during silver–oxygen nanoparticle catalysed oxidation of carbon nanotubes

PubMed Central

Yue, Yonghai; Yuchi, Datong; Guan, Pengfei; Xu, Jia; Guo, Lin; Liu, Jingyue

2016-01-01

To probe the nature of metal-catalysed processes and to design better metal-based catalysts, atomic scale understanding of catalytic processes is highly desirable. Here we use aberration-corrected environmental transmission electron microscopy to investigate the atomic scale processes of silver-based nanoparticles, which catalyse the oxidation of multi-wall carbon nanotubes. A direct semi-quantitative estimate of the oxidized carbon atoms by silver-based nanoparticles is achieved. A mechanism similar to the Mars–van Krevelen process is invoked to explain the catalytic oxidation process. Theoretical calculations, together with the experimental data, suggest that the oxygen molecules dissociate on the surface of silver nanoparticles and diffuse through the silver nanoparticles to reach the silver/carbon interfaces and subsequently oxidize the carbon. The lattice distortion caused by oxygen concentration gradient within the silver nanoparticles provides the direct evidence for oxygen diffusion. Such direct observation of atomic scale dynamics provides an important general methodology for investigations of catalytic processes. PMID:27406595

Structure and anticancer activity of sulfated O-polysaccharide from marine bacterium Cobetia litoralis KMM 3880(T).

PubMed

Kokoulin, Maxim S; Kuzmich, Alexandra S; Kalinovsky, Anatoly I; Tomshich, Svetlana V; Romanenko, Lyudmila A; Mikhailov, Valery V; Komandrova, Nadezhda A

2016-12-10

We presented the structure of the polysaccharide moiety and anticancer activity in vitro of the sulfated lipopolysaccharide isolated from the marine bacterium Cobetia litoralis KMM 3880(T). The structure of O-polysaccharide was investigated by chemical methods along with (1)H and (13)C NMR spectroscopy. The O-polysaccharide was built up of branched trisaccharide repeating units consist of D-glucose (D-Glcр), D-mannose (D-Manр) and sulfated 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo5S): →7-β-Kdoр4Ac5S-(2→4)-[β-d-Glcp-(1→2)-]-β-d-Manр6Ac-1→. We demonstrated that the lipopolysaccharide and О-deacetylated O-polysaccharide from Cobetia litoralis KMM 3880(T) inhibited a colony formation of human melanoma SK-MEL-28 and colorectal carcinoma HTC-116 cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

GSDC: A Unique Data Center in Korea for HEP research

NASA Astrophysics Data System (ADS)

Ahn, Sang-Un

2017-04-01

Global Science experimental Data hub Center (GSDC) at Korea Institute of Science and Technology Information (KISTI) is a unique data center in South Korea established for promoting the fundamental research fields by supporting them with the expertise on Information and Communication Technology (ICT) and the infrastructure for High Performance Computing (HPC), High Throughput Computing (HTC) and Networking. GSDC has supported various research fields in South Korea dealing with the large scale of data, e.g. RENO experiment for neutrino research, LIGO experiment for gravitational wave detection, Genome sequencing project for bio-medical, and HEP experiments such as CDF at FNAL, Belle at KEK, and STAR at BNL. In particular, GSDC has run a Tier-1 center for ALICE experiment using the LHC at CERN since 2013. In this talk, we present the overview on computing infrastructure that GSDC runs for the research fields and we discuss on the data center infrastructure management system deployed at GSDC.

Decentralized Grid Scheduling with Evolutionary Fuzzy Systems

NASA Astrophysics Data System (ADS)

Fölling, Alexander; Grimme, Christian; Lepping, Joachim; Papaspyrou, Alexander

In this paper, we address the problem of finding workload exchange policies for decentralized Computational Grids using an Evolutionary Fuzzy System. To this end, we establish a non-invasive collaboration model on the Grid layer which requires minimal information about the participating High Performance and High Throughput Computing (HPC/HTC) centers and which leaves the local resource managers completely untouched. In this environment of fully autonomous sites, independent users are assumed to submit their jobs to the Grid middleware layer of their local site, which in turn decides on the delegation and execution either on the local system or on remote sites in a situation-dependent, adaptive way. We find for different scenarios that the exchange policies show good performance characteristics not only with respect to traditional metrics such as average weighted response time and utilization, but also in terms of robustness and stability in changing environments.

Ocean Biological Pump Sensitivities and Implications for Climate Change Impacts

NASA Technical Reports Server (NTRS)

Romanou, Anastasia

2013-01-01

The ocean is one of the principal reservoirs of CO2, a greenhouse gas, and therefore plays a crucial role in regulating Earth's climate. Currently, the ocean sequesters about a third of anthropogenic CO2 emissions, mitigating the human impact on climate. At the same time, the deeper ocean represents the largest carbon pool in the Earth System and processes that describe the transfer of carbon from the surface of the ocean to depth are intimately linked to the effectiveness of carbon sequestration.The ocean biological pump (OBP), which involves several biogeochemical processes, is a major pathway for transfer of carbon from the surface mixed layer into the ocean interior. About 75 of the carbon vertical gradient is due to the carbon pump with only 25 attributed to the solubility pump. However, the relative importance and role of the two pumps is poorly constrained. OBP is further divided to the organic carbon pump (soft tissue pump) and the carbonate pump, with the former exporting about 10 times more carbon than the latter through processes like remineralization.Major uncertainties about OBP, and hence in the carbon uptake and sequestration, stem from uncertainties in processes involved in OBP such as particulate organicinorganic carbon sinkingsettling, remineralization, microbial degradation of DOC and uptakegrowth rate changes of the ocean biology. The deep ocean is a major sink of atmospheric CO2 in scales of hundreds to thousands of years, but how the export efficiency (i.e. the fraction of total carbon fixation at the surface that is transported at depth) is affected by climate change remains largely undetermined. These processes affect the ocean chemistry (alkalinity, pH, DIC, particulate and dissolved organic carbon) as well as the ecology (biodiversity, functional groups and their interactions) in the ocean. It is important to have a rigorous, quantitative understanding of the uncertainties involved in the observational measurements, the models and the projections of future changes.

Characteristics of activated carbon resulted from pyrolysis of the oil palm fronds powder

NASA Astrophysics Data System (ADS)

Maulina, S.; Iriansyah, M.

2018-02-01

Activated carbon is the product of a charcoal impregnation process that has a higher absorption capacity and has more benefits than regular char. Therefore, this study aims to cultivate the powder of oil palm fronds into activated carbon that meets the requirements of Standard National Indonesia 06-3730-1995. To do so, the carbonization process of the powder of oil palm fronds was carried out using a pyrolysis reactor for 30 minutes at a temperature of 150 °C, 200 °C, and 250 °C in order to produce activated char. Then, the char was impregnated using Phosphoric Acid activator (H3PO4) for 24 hours. Characteristics of activated carbon indicate that the treatment of char by chemical activation of oil palm fronds powder has an effect on the properties of activated carbon. The activated carbons that has the highest absorption properties to Iodine (822.91 mg/g) were obtained from the impregnation process with 15% concentration of Phosphoric Acid (H3PO4) at pyrolysis temperature of 200 °C. Furthermore, the activation process resulted in activated carbon with water content of 8%, ash content of 4%, volatile matter 39%, and fixed carbon 75%, Iodine number 822.91 mg/g.

Capacitor with a composite carbon foam electrode

DOEpatents

Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

1999-01-01

Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid partides being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy.

Method for fabricating composite carbon foam

DOEpatents

Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

2001-01-01

Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy.

Capacitor with a composite carbon foam electrode

DOEpatents

Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

1999-04-27

Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

Composite carbon foam electrode

DOEpatents

Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

1997-05-06

Carbon aerogels used as a binder for granulated materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

Typical calculation and analysis of carbon emissions in thermal power plants

NASA Astrophysics Data System (ADS)

Gai, Zhi-jie; Zhao, Jian-gang; Zhang, Gang

2018-03-01

On December 19, 2017, the national development and reform commission issued the national carbon emissions trading market construction plan (power generation industry), which officially launched the construction process of the carbon emissions trading market. The plan promotes a phased advance in carbon market construction, taking the power industry with a large carbon footprint as a breakthrough, so it is extremely urgent for power generation plants to master their carbon emissions. Taking a coal power plant as an example, the paper introduces the calculation process of carbon emissions, and comes to the fuel activity level, fuel emissions factor and carbon emissions data of the power plant. Power plants can master their carbon emissions according to this paper, increase knowledge in the field of carbon reserves, and make the plant be familiar with calculation method based on the power industry carbon emissions data, which can help power plants positioning accurately in the upcoming carbon emissions trading market.

Thermal Oxidation of a Carbon Condensate Formed in High-Frequency Carbon and Carbon-Nickel Plasma Flow

NASA Astrophysics Data System (ADS)

Churilov, G. N.; Nikolaev, N. S.; Cherepakhin, A. V.; Dudnik, A. I.; Tomashevich, E. V.; Trenikhin, M. V.; Bulina, N. G.

2018-02-01

We have reported on the comparative characteristics of thermal oxidation of a carbon condensate prepared by high-frequency arc evaporation of graphite rods and a rod with a hollow center filled with nickel powder. In the latter case, along with different forms of nanodisperse carbon, nickel particles with nickel core-carbon shell structures are formed. It has been found that the processes of the thermal oxidation of carbon condensates with and without nickel differ significantly. Nickel particles with the carbon shell exhibit catalytic properties with respect to the oxidation of nanosized carbon structures. A noticeable difference between the temperatures of the end of the oxidation process for various carbon nanoparticles and nickel particles with the carbon shell has been established. The study is aimed at investigations of the effect of nickel nanoparticles on the dynamics of carbon condensate oxidation upon heating in the argon-oxygen flow.

Study on the Carbonation Behavior of Cement Mortar by Electrochemical Impedance Spectroscopy

PubMed Central

Dong, Biqin; Qiu, Qiwen; Xiang, Jiaqi; Huang, Canjie; Xing, Feng; Han, Ningxu

2014-01-01

A new electrochemical model has been carefully established to explain the carbonation behavior of cement mortar, and the model has been validated by the experimental results. In fact, it is shown by this study that the electrochemical impedance behavior of mortars varies in the process of carbonation. With the cement/sand ratio reduced, the carbonation rate reveals more remarkable. The carbonation process can be quantitatively accessed by a parameter, which can be obtained by means of the electrochemical impedance spectroscopy (EIS)-based electrochemical model. It has been found that the parameter is a function of carbonation depth and of carbonation time. Thereby, prediction of carbonation depth can be achieved. PMID:28788452

Study on the Carbonation Behavior of Cement Mortar by Electrochemical Impedance Spectroscopy.

PubMed

Dong, Biqin; Qiu, Qiwen; Xiang, Jiaqi; Huang, Canjie; Xing, Feng; Han, Ningxu

2014-01-03

A new electrochemical model has been carefully established to explain the carbonation behavior of cement mortar, and the model has been validated by the experimental results. In fact, it is shown by this study that the electrochemical impedance behavior of mortars varies in the process of carbonation. With the cement/sand ratio reduced, the carbonation rate reveals more remarkable. The carbonation process can be quantitatively accessed by a parameter, which can be obtained by means of the electrochemical impedance spectroscopy (EIS)-based electrochemical model. It has been found that the parameter is a function of carbonation depth and of carbonation time. Thereby, prediction of carbonation depth can be achieved.

Adsorption of sodium dodecylbenzenesulfonate on activated carbons: effects of solution chemistry and presence of bacteria.

PubMed

Bautista-Toledo, M I; Méndez-Díaz, J D; Sánchez-Polo, M; Rivera-Utrilla, J; Ferro-García, M A

2008-01-01

The objective of the present investigation was to determine the effectiveness of activated carbon in removing sodium dodecylbenzenesulfonate (SDBS) and to analyze the chemical and textural characteristics of the activated carbons that are involved in the adsorption process. Studies were also performed on the influence of operational variables (pH, ionic strength, and presence of microorganisms) and on the kinetics and interactions involved in the adsorption of this pollutant on activated carbon. The kinetics study of SDBS adsorption revealed no problems in its diffusion on any of the activated carbons studied, and Weisz-Prater coefficient (C WP) values were considerably lower than unity for all activated carbons studied. SDBS adsorption isotherms on these activated carbons showed that: (i) adsorption capacity of activated carbons was very high (260-470 mg/g) and increased with larger surface area; and (ii) dispersive interactions between SDBS and carbon surface were largely responsible for the adsorption of this pollutant. SDBS adsorption was not significantly affected by the solution pH, indicating that electrostatic adsorbent-adsorbate interactions do not play an important role in this process. The presence of electrolytes (NaCl) in the medium favors SDBS adsorption, accelerating the process and increasing adsorption capacity. Under the working conditions used, SDBS is not degraded by bacteria; however, the presence of bacteria during the process accelerates and increases SDBS adsorption on the activated carbon. Microorganism adsorption on the activated carbon surface increases its hydrophobicity, explaining the results observed.

Understanding the Carbon Cycle : A Jigsaw Approach

NASA Astrophysics Data System (ADS)

Hastings, D. W.

2006-12-01

A thorough understanding of the carbon cycle is fundamental to understanding the eventual fate of CO2. To achieve this, students must understand individual processes, such as photosynthesis and respiration, as well as an integrated knowledge of how these processes relate to each other. In this "jigsaw" exercise, each student is assigned one five fundamental geochemical processes in the short- term carbon cycle to research and fully understand. In class, students first meet with others who have studied the same process to strengthen and deepen their understanding of this process. They then form teams of five students and explain to other students their particular process. In exchange, other students explain the other aspects of the carbon cycle. At the end of class all students will know about each of the five processes, and thus develop an integrated understanding of the entire carbon cycle. This approach is an efficient method for students to learn the material. As in a jigsaw puzzle, each student's part is essential for the full understanding of the carbon cycle. Since each student's part is essential, then each student is essential, which is what makes this strategy effective The jigsaw approach encourages listening, engagement, and collaboration by giving each member of the group an essential part to play in the academic activity.

Grape stalks biomass as raw material for activated carbon production: synthesis, characterization and adsorption ability

NASA Astrophysics Data System (ADS)

Hashemi Shahraki, Zahra; Sharififard, Hakimeh; Lashanizadegan, Asghar

2018-05-01

In order to produce activated carbon from grape stalks, this biomass was activated chemically with KOH. Identification methods including FTIR, BET, SEM, Boehm titration and pHzpc measurement were applied to characterize the produced carbon. The adsorption ability of produced activated carbon toward cadmium removal from aqueous solution was evaluated by using Central Composite Design methodology and the effects of process parameters were analysed, as well as, the optimum processing conditions were determined using statistical methods. In order to characterize the equilibrium behaviour of adsorption process, the equilibrium data were analysed by Langmuir, Freundlich, and R-D isotherm models. Results indicated that the adsorption process is a monolayer process and the adsorption capacity of prepared activated carbon was 140.84 mg L‑1. Analysis of kinetics data showed that the pseudo-second-order and Elovich models were well fitted with the kinetics results and this suggests the domination of chemical adsorption. The regenerability results showed that the prepared activated carbon has a reasonable adsorption capacity toward cadmium after five adsorption/desorption cycles.

Additive-free carbon nanotube dispersions, pastes, gels, and doughs in cresols.

PubMed

Chiou, Kevin; Byun, Segi; Kim, Jaemyung; Huang, Jiaxing

2018-05-29

Cresols are a group of naturally occurring and massively produced methylphenols with broad use in the chemical industry. Here, we report that m -cresol and its liquid mixtures with other isomers are surprisingly good solvents for processing carbon nanotubes. They can disperse carbon nanotubes of various types at unprecedentedly high concentrations of tens of weight percent, without the need for any dispersing agent or additive. Cresols interact with carbon nanotubes by charge transfer through the phenolic hydroxyl proton and can be removed after processing by evaporation or washing, without altering the surface of carbon nanotubes. Cresol solvents render carbon nanotubes polymer-like rheological and viscoelastic properties and processability. As the concentration of nanotubes increases, a continuous transition of four states can be observed, including dilute dispersion, thick paste, free-standing gel, and eventually a kneadable, playdough-like material. As demonstrated with a few proofs of concept, cresols make powders of agglomerated carbon nanotubes immediately usable by a broad array of material-processing techniques to create desirable structures and form factors and make their polymer composites.

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

Matsumura, Yukihiko; Nuessle, F.W.; Antal, M.J. Jr.

Recently, carbonaceous materials including activated carbon were proven to be effective catalysts for hazardous waste gasification in supercritical water. Using coconut shell activated carbon catalyst, complete decomposition of industrial organic wastes including methanol and acetic acid was achieved. During this process, the total mass of the activated carbon catalyst changes by two competing processes: a decrease in weight via gasification of the carbon by supercritical water, or an increase in weight by deposition of carbonaceous materials generated by incomplete gasification of the biomass feedstocks. The deposition of carbonaceous materials does not occur when complete gasification is realized. Gasification of themore » activated carbon in supercritical water is often favored, resulting in changes in the quality and quantity of the catalyst. To thoroughly understand the hazardous waste decomposition process, a more complete understanding of the behavior of activated carbon in pure supercritical water is needed. The gasification rate of carbon by water vapor at subcritical pressures was studied in relation to coal gasification and generating activated carbon.« less

Intense Electrochemical Oxidation on Graphitized Carbon Electrodes in the Presence of Ozone

NASA Astrophysics Data System (ADS)

Klochikhin, V. L.; Potapova, G. F.; Putilov, A. V.

2018-06-01

A new intense oxidation process for water treatment in which oxidation with ozone is coupled to electrochemical processes is described, and the results from its application to water purification are presented along with the discussion of its practical implementation. The use of graphitized carbon materials for this process is explained and tested experimentally. The use of glassy carbon for the anode enables us to achieve very high (up to 25 vol %) concentrations of ozone in the generated ozone-oxygen mixture. The material used for the cathode—graphitized carbon cloth (GCC) reinforced with Ni allows different electrocatalytic processes to proceed on its developed surface, and combines the high sorption capacity of this cathode and potentialcontrolled selectivity of cathodic electrochemical processes.

Carbon nanofibers obtained from electrospinning process

NASA Astrophysics Data System (ADS)

Bovi de Oliveira, Juliana; Müller Guerrini, Lília; Sizuka Oishi, Silvia; Rogerio de Oliveira Hein, Luis; dos Santos Conejo, Luíza; Cerqueira Rezende, Mirabel; Cocchieri Botelho, Edson

2018-02-01

In recent years, reinforcements consisting of carbon nanostructures, such as carbon nanotubes, fullerenes, graphenes, and carbon nanofibers have received significant attention due mainly to their chemical inertness and good mechanical, electrical and thermal properties. Since carbon nanofibers comprise a continuous reinforcing with high specific surface area, associated with the fact that they can be obtained at a low cost and in a large amount, they have shown to be advantageous compared to traditional carbon nanotubes. The main objective of this work is the processing of carbon nanofibers, using polyacrylonitrile (PAN) as a precursor, obtained by the electrospinning process via polymer solution, with subsequent use for airspace applications as reinforcement in polymer composites. In this work, firstly PAN nanofibers were produced by electrospinning with diameters in the range of (375 ± 85) nm, using a dimethylformamide solution. Using a furnace, the PAN nanofiber was converted into carbon nanofiber. Morphologies and structures of PAN and carbon nanofibers were investigated by scanning electron microscopy, Raman Spectroscopy, thermogravimetric analyses and differential scanning calorimeter. The resulting residual weight after carbonization was approximately 38% in weight, with a diameters reduction of 50%, and the same showed a carbon yield of 25%. From the analysis of the crystalline structure of the carbonized material, it was found that the material presented a disordered structure.

ACTIVATED CARBON PROCESS FOR TREATMENT OF WASTEWATERS CONTAINING HEXAVALENT CHROMIUM

EPA Science Inventory

The removal of hexavalent chromium, Cr(VI), from dilute aqueous solution by an activated carbon process has been investigated. Two removal mechanisms were observed; hexavalent chromium species were removed by adsorption onto the interior carbon surface and/or through reduction to...

Carbothermal Processing of Lunar Regolith Using Methane

NASA Technical Reports Server (NTRS)

Balasubramaniam, R.; Hegde, U.; Gokoglu, S.

2009-01-01

The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans currently being developed by NASA. Among various candidate processes, the modeling of oxygen production by hydrogen reduction, molten salt electrolysis, and carbothermal processing are presently being pursued. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source such as a laser beam or a concentrated solar heat flux, so that a small zone of molten regolith is established. The molten zone is surrounded by solid regolith particles that are poor conductors of heat. A continuous flow of methane is maintained over the molten regolith zone. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. Oxygen is produced subsequently by (catalytically) processing the carbon monoxide downstream. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide.

Carbothermal Processing of Lunar Regolith Using Methane

NASA Technical Reports Server (NTRS)

Balasubramaniam, R.; Hegde, U.; Gokoglu, S.

2008-01-01

The processing of lunar regolith for the production of oxygen is a key component of the In-Situ Resource Utilization plans currently being developed by NASA. Among various candidate processes, the modeling of oxygen production by hydrogen reduction, molten salt electrolysis, and carbothermal processing are presently being pursued. In the carbothermal process, a portion of the surface of the regolith in a container is heated by exposure to a heat source such as a laser beam or a concentrated solar heat flux, so that a small zone of molten regolith is established. The molten zone is surrounded by solid regolith particles that are poor conductors of heat. A continuous flow of methane is maintained over the molten regolith zone. Our model is based on a mechanism where methane pyrolyzes when it comes in contact with the surface of the hot molten regolith to form solid carbon and hydrogen gas. Carbon is deposited on the surface of the melt, and hydrogen is released into the gas stream above the melt surface. We assume that the deposited carbon mixes in the molten regolith and reacts with metal oxides in a reduction reaction by which gaseous carbon monoxide is liberated. Carbon monoxide bubbles through the melt and is released into the gas stream. Oxygen is produced subsequently by (catalytically) processing the carbon monoxide downstream. In this paper, we discuss the development of a chemical conversion model of the carbothermal process to predict the rate of production of carbon monoxide.

Surprising synthesis of nanodiamond from single-walled carbon nanotubes by the spark plasma sintering process

NASA Astrophysics Data System (ADS)

Mirzaei, Ali; Ham, Heon; Na, Han Gil; Kwon, Yong Jung; Kang, Sung Yong; Choi, Myung Sik; Bang, Jae Hoon; Park, No-Hyung; Kang, Inpil; Kim, Hyoun Woo

2016-10-01

Nanodiamond (ND) was successfully synthesized using single-walled carbon nanotubes (SWCNTs) as a pure solid carbon source by means of a spark plasma sintering process. Raman spectra and X-ray diffraction patterns revealed the generation of the cubic diamond phase by means of the SPS process. Lattice-resolved TEM images confirmed that diamond nanoparticles with a diameter of about ˜10 nm existed in the products. The NDs were generated mainly through the gas-phase nucleation of carbon atoms evaporated from the SWCNTs. [Figure not available: see fulltext.

Carbon wastewater treatment process

NASA Technical Reports Server (NTRS)

Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.

1974-01-01

A new powdered-carbon treatment process is being developed for the elimination of the present problems, associated with the disposal of biologically active sewage waste solids, and with water reuse. This counter-current flow process produces an activated carbon, which is obtained from the pyrolysis of the sewage solids, and utilizes this material to remove the adulterating materials from the water. Additional advantages of the process are the elimination of odors, the removal of heavy metals, and the potential for energy conservation.

Processes for preparing carbon fibers using sulfur trioxide in a halogenated solvent

DOEpatents

Patton, Jasson T.; Barton, Bryan E.; Bernius, Mark T.; Chen, Xiaoyun; Hukkanen, Eric J.; Rhoton, Christina A.; Lysenko, Zenon

2015-12-29

Disclosed here are processes for preparing carbonized polymers (preferably carbon fibers), comprising sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 dissolved in a solvent to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of the solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C. Carbon fibers made according to these methods are also disclosed herein.

Carbon-carbon mirrors for exoatmospheric and space applications

NASA Astrophysics Data System (ADS)

Krumweide, Duane E.; Wonacott, Gary D.; Woida, Patrick M.; Woida, Rigel Q.; Shih, Wei

2007-09-01

The cost and leadtime associated with beryllium has forced the MDA and other defense agencies to look for alternative materials with similar structural and thermal properties. The use of carbon-carbon material, specifically in optical components has been demonstrated analytically in prior SBIR work at San Diego Composites. Carbon-carbon material was chosen for its low in-plane and through-thickness CTE (athermal design), high specific stiffness, near-zero coefficient of moisture expansion, availability of material (specifically c-c honeycomb for lightweight substrates), and compatibility with silicon monoxide (SiO) and silicon dioxide (SiO II) coatings. Subsequent development work has produced shaped carbon-carbon sandwich substrates which have been ground, polished, coated and figured using traditional optical processing. Further development has also been done on machined monolithic carbon-carbon mirror substrates which have also been processed using standard optical finishing techniques.

Impact of a Regional Drought on Terrestrial Carbon Fluxes and Atmospheric Carbon: Results from a Coupled Carbon Cycle Model

NASA Technical Reports Server (NTRS)

Lee, Eunjee; Koster, Randal D.; Ott, Lesley E.; Weir, Brad; Mahanama, Sarith; Chang, Yehui; Zeng, Fan-Wei

2017-01-01

Understanding the underlying processes that control the carbon cycle is key to predicting future global change. Much of the uncertainty in the magnitude and variability of the atmospheric carbon dioxide (CO2) stems from uncertainty in terrestrial carbon fluxes, and the relative impacts of temperature and moisture variations on regional and global scales are poorly understood. Here we investigate the impact of a regional drought on terrestrial carbon fluxes and CO2 mixing ratios over North America using the NASA Goddard Earth Observing System (GEOS) Model. Results show a sequence of changes in carbon fluxes and atmospheric CO2, induced by the drought. The relative contributions of meteorological changes to the neighboring carbon dynamics are also presented. The coupled modeling approach allows a direct quantification of the impact of the regional drought on local and proximate carbon exchange at the land surface via the carbon-water feedback processes.

Modelling the impacts of barrier-island transgression and anthropogenic disturbance on blue carbon budgets

NASA Astrophysics Data System (ADS)

Theuerkauf, E. J.; Rodriguez, A. B.

2017-12-01

The size of backbarrier saltmarsh carbon reservoirs are dictated by transgressive processes, such as erosion and overwash, yet these processes are not included in blue carbon budgets. These carbon reservoirs are presumed to increase through time if marsh elevation is keeping pace with sea-level rise. However, changes in marsh width due to erosion and overwash can alter carbon budgets and reservoirs. To explore the impacts of these processes on transgressive barrier island carbon budgets and reservoirs we developed and tested a transect model. The model couples a carbon storage term driven by backbarrier marsh width and a carbon export term driven by ocean and backbarrier shoreline erosion. We tested the model using data collected from two transgressive barrier islands in North Carolina with different backbarrier settings. Core Banks is an undeveloped barrier island with a wide backbarrier marsh and lagoon, hence, landward migration of the island (rollover) is unimpeded. Barrier rollover is impeded at Onslow Beach as there is no backbarrier lagoon and the island is immediately adjacent to steeper mainland topography. Sediment cores were collected to determine carbon storage rates as well as the quantity of carbon exported from eroding marsh. Backbarrier marsh erosion rates, ocean shoreline erosion rates, and changes in marsh width were determined from aerial photographs. Output from the model indicated that hurricane erosion and overwash as well as human disturbance from the construction of the Intracoastal Waterway temporarily transitioned the Onslow Beach sites to carbon sources. Through time, the carbon reservoir at this barrier continued to decrease as carbon export outpaced carbon storage. The carbon reservoir will continue to exhaust as the ocean shoreline migrates landward given the inability for new marsh to form during island rollover. At Core Banks, barrier rollover is unimpeded and new saltmarsh can form during transgression. The Core Banks site only briefly became a carbon source during an erosive period; otherwise the island functioned as a carbon sink and the reservoir increased across the past century. Our model results indicate barrier island setting controls the sustainability of the carbon reservoir and that transgressive processes should be included in coastal carbon budgets.

Material Characterization for Composite Materials in Load Bearing Wave Guides

DTIC Science & Technology

2012-03-01

ISIS Integrated Sensor Is Structure MUSTRAP Multifunctional Structural Aperture MWCNT Multi-walled Carbon Nanotube SWCNT Single-walled Carbon...CNTs go through a specific process to coat them with nickel. The process includes conditioning the CNTs in different solutions and adding...a single-walled carbon nanotube (SWCNT), a multi-walled carbon nanotube ( MWCNT ), or a graphene nanoribbon (GNR). A SWCNT is a hollow cylindrical

Novel two stage bio-oxidation and chlorination process for high strength hazardous coal carbonization effluent.

PubMed

Manekar, Pravin; Biswas, Rima; Karthik, Manikavasagam; Nandy, Tapas

2011-05-15

Effluent generated from coal carbonization to coke was characterized with high organic content, phenols, ammonium nitrogen, and cyanides. A full scale effluent treatment plant (ETP) working on the principle of single stage carbon-nitrogen bio-oxidation process (SSCNBP) revealed competition between heterotrophic and autotrophic bacteria in the bio-degradation and nitrification process. The effluent was pretreated in a stripper and further combined with other streams to treat in the SSCNBP. Laboratory studies were carried on process and stripped effluents in a bench scale model of ammonia stripper and a two stage bio-oxidation process. The free ammonia removal efficiency of stripper was in the range 70-89%. Bench scale studies of the two stage bio-oxidation process achieved a carbon-nitrogen reduction at 6 days hydraulic retention time (HRT) operating in an extended aeration mode. This paper addresses the studies on selection of a treatment process for removal of organic matter, phenols, cyanide and ammonia nitrogen. The treatment scheme comprising ammonia stripping (pretreatment) followed by the two stage bio-oxidation and chlorination process met the Indian Standards for discharge into Inland Surface Waters. This treatment process package offers a techno-economically viable treatment scheme to neuter hazardous effluent generated from coal carbonization process. Copyright © 2011 Elsevier B.V. All rights reserved.

Effective utilizations of palm oil mill fly ash for synthetic amorphous silica and carbon zeolite composite synthesis

NASA Astrophysics Data System (ADS)

Utama, P. S.; Saputra, E.; Khairat

2018-04-01

Palm Oil Mill Fly Ash (POMFA) the solid waste of palm oil industry was used as a raw material for synthetic amorphous silica and carbon zeolite composite synthesis in order to minimize the wastes of palm oil industry. The alkaline extraction combine with the sol-gel precipitation and mechanical fragmentation was applied to produce synthetic amorphous silica. The byproduct, extracted POMFA was rich in carbon and silica content in a significant amount. The microwave heated hydrothermal process used to synthesize carbon zeolite composite from the byproduct. The obtained silica had chemical composition, specific surface area and the micrograph similar to commercial precipitated silica for rubber filler. The microwave heated hydrothermal process has a great potential for synthesizing carbon zeolite composite. The process only needs one-step and shorter time compare to conventional hydrothermal process.

Microbially-induced Carbonate Precipitation for Immobilization of Toxic Metals.

PubMed

Kumari, Deepika; Qian, Xin-Yi; Pan, Xiangliang; Achal, Varenyam; Li, Qianwei; Gadd, Geoffrey Michael

2016-01-01

Rapid urbanization and industrialization resulting from growing populations contribute to environmental pollution by toxic metals and radionuclides which pose a threat to the environment and to human health. To combat this threat, it is important to develop remediation technologies based on natural processes that are sustainable. In recent years, a biomineralization process involving ureolytic microorganisms that leads to calcium carbonate precipitation has been found to be effective in immobilizing toxic metal pollutants. The advantage of using ureolytic organisms for bioremediating metal pollution in soil is their ability to immobilize toxic metals efficiently by precipitation or coprecipitation, independent of metal valence state and toxicity and the redox potential. This review summarizes current understanding of the ability of ureolytic microorganisms for carbonate biomineralization and applications of this process for toxic metal bioremediation. Microbial metal carbonate precipitation may also be relevant to detoxification of contaminated process streams and effluents as well as the production of novel carbonate biominerals and biorecovery of metals and radionuclides that form insoluble carbonates. Copyright © 2016 Elsevier Inc. All rights reserved.

Substantial global carbon uptake by cement carbonation

NASA Astrophysics Data System (ADS)

Xi, Fengming; Davis, Steven J.; Ciais, Philippe; Crawford-Brown, Douglas; Guan, Dabo; Pade, Claus; Shi, Tiemao; Syddall, Mark; Lv, Jie; Ji, Lanzhu; Bing, Longfei; Wang, Jiaoyue; Wei, Wei; Yang, Keun-Hyeok; Lagerblad, Björn; Galan, Isabel; Andrade, Carmen; Zhang, Ying; Liu, Zhu

2016-12-01

Calcination of carbonate rocks during the manufacture of cement produced 5% of global CO2 emissions from all industrial process and fossil-fuel combustion in 2013. Considerable attention has been paid to quantifying these industrial process emissions from cement production, but the natural reversal of the process--carbonation--has received little attention in carbon cycle studies. Here, we use new and existing data on cement materials during cement service life, demolition, and secondary use of concrete waste to estimate regional and global CO2 uptake between 1930 and 2013 using an analytical model describing carbonation chemistry. We find that carbonation of cement materials over their life cycle represents a large and growing net sink of CO2, increasing from 0.10 GtC yr-1 in 1998 to 0.25 GtC yr-1 in 2013. In total, we estimate that a cumulative amount of 4.5 GtC has been sequestered in carbonating cement materials from 1930 to 2013, offsetting 43% of the CO2 emissions from production of cement over the same period, not including emissions associated with fossil use during cement production. We conclude that carbonation of cement products represents a substantial carbon sink that is not currently considered in emissions inventories.

Study for new hardmask process scheme

NASA Astrophysics Data System (ADS)

Lee, Daeyoup; Tatti, Phillip; Lee, Richard; Chang, Jack; Cho, Winston; Bae, Sanggil

2017-03-01

Hardmask processes are a key technique to enable low-k semiconductors, but they can have an impact on patterning control, influencing defectivity, alignment, and overlay. Specifically, amorphous carbon layer (ACL) hardmask schemes can negatively affect overlay by creating distorted alignment signals. A new scheme needs to be developed that can be inserted where amorphous carbon is used but provide better alignment performance. Typical spin-on carbon (SOC) materials used in other hardmask schemes have issues with DCD-FCD skew. In this paper we will evaluate new spin-on carbon material with a higher carbon content that could be a candidate to replace amorphous carbon.

Cyclic process for producing methane in a tubular reactor with effective heat removal

DOEpatents

Frost, Albert C.; Yang, Chang-Lee

1986-01-01

Carbon monoxide-containing gas streams are converted to methane by a cyclic, essentially two-step process in which said carbon monoxide is disproportionated to form carbon dioxide and active surface carbon deposited on the surface of a catalyst, and said carbon is reacted with steam to form product methane and by-product carbon dioxide. The exothermic heat of reaction generated in each step is effectively removed during each complete cycle so as to avoid a build up of heat from cycle-to-cycle, with particularly advantageous techniques being employed for fixed bed, tubular and fluidized bed reactor operations.

Laser Processing of Carbon Fiber Reinforced Plastics - Release of Carbon Fiber Segments During Short-pulsed Laser Processing of CFRP

NASA Astrophysics Data System (ADS)

Walter, Juergen; Brodesser, Alexander; Hustedt, Michael; Bluemel, Sven; Jaeschke, Peter; Kaierle, Stefan

Cutting and ablation using short-pulsed laser radiation are promising technologies to produce or repair CFRP components with outstanding mechanical properties e.g. for automotive and aircraft industry. Using sophisticated laser processing strategies and avoiding excessive heating of the workpiece, a high processing quality can be achieved. However, the interaction of laser radiation and composite material causes a notable release of hazardous substances from the process zone, amongst others carbon fiber segments or fibrous particles. In this work, amounts and geometries of the released fiber segments are analyzed and discussed in terms of their hazardous potential. Moreover, it is investigated to what extent gaseous organic process emissions are adsorbed at the fiber segments, similar to an adsorption of volatile organic compounds at activated carbon, which is typically used as filter material.

Supercritical carbon dioxide for textile applications and recent developments

NASA Astrophysics Data System (ADS)

Eren, H. A.; Avinc, O.; Eren, S.

2017-10-01

In textile industry, supercritical carbon dioxide (scCO2), possessing liquid-like densities, mostly find an application on textile dyeing processes such as providing hydrophobic dyes an advantage on dissolving. Their gas-like low viscosities and diffusion properties can result in shorter dyeing periods in comparison with the conventional water dyeing process. Supercritical carbon dioxide dyeing is an anhydrous dyeing and this process comprises the usage of less energy and chemicals when compared to conventional water dyeing processes leading to a potential of up to 50% lower operation costs. The advantages of supercritical carbon dioxide dyeing method especially on synthetic fiber fabrics hearten leading textile companies to alter their dyeing method to this privileged waterless dyeing technology. Supercritical carbon dioxide (scCO2) waterless dyeing is widely known and applied green method for sustainable and eco-friendly textile industry. However, not only the dyeing but also scouring, desizing and different finishing applications take the advantage of supercritical carbon dioxide (scCO2). In this review, not only the principle, advantages and disadvantages of dyeing in supercritical carbon dioxide but also recent developments of scCO2 usage in different textile processing steps such as scouring, desizing and finishing are explained and commercial developments are stated and summed up.

Using Virtual Reality For Outreach Purposes in Planetology

NASA Astrophysics Data System (ADS)

Civet, François; Le Mouélic, Stéphane; Le Menn, Erwan; Beaunay, Stéphanie

2016-10-01

2016 has been a year marked by a technological breakthrough : the availability for the first time to the general public of technologically mature virtual reality devices. Virtual Reality consists in visually immerging a user in a 3D environment reproduced either from real and/or imaginary data, with the possibility to move and eventually interact with the different elements. In planetology, most of the places will remain inaccessible to the public for a while, but a fleet of dedicated spacecraft's such as orbiters, landers and rovers allow the possibility to virtually reconstruct the environments, using image processing, cartography and photogrammetry. Virtual reality can then bridge the gap to virtually "send" any user into the place and enjoy the exploration.We are investigating several type of devices to render orbital or ground based data of planetological interest, mostly from Mars. The most simple system consists of a "cardboard" headset, on which the user can simply use his cellphone as the screen. A more comfortable experience is obtained with more complex systems such as the HTC vive or Oculus Rift headsets, which include a tracking system important to minimize motion sickness. The third environment that we have developed is based on the CAVE concept, were four 3D video projectors are used to project on three 2x3m walls plus the ground. These systems can be used for scientific data analysis, but also prove to be perfectly suited for outreach and education purposes.

The biokarst system and its carbon sinks in response to pH changes: A simulation experiment with microalgae

NASA Astrophysics Data System (ADS)

Xie, Tengxiang; Wu, Yanyou

2017-03-01

This study aims to explore the changes in a microalgal biokarst system as a potential carbon sink system in response to pH changes. The bidirectional isotope labeling method and mass balance calculation were adopted in a simulated biokarst environment with a series of set pH conditions and three microalgal species. Three key processes of the microalgal biokarst system, including calcite dissolution, CaCO3 reprecipitation, and inorganic carbon assimilation by microalgae, were completely quantitatively described. The combined effects of chemical dissolution and species-specific biodissolution caused a decrease in overall dissolution rate when the pH increased from 7 to 9. CaCO3 reprecipitation and the utilization of dissolved inorganic carbon originating from calcite dissolution decreased when the pH increased from 7 to 9. The three processes exhibited different effects in changing the CO2 atmosphere. The amount of photosynthetic carbon sink was larger at high pH values than at low pH values. However, the CO2 sequestration related to the biokarst process (biokarst carbon sink) increased with decreasing pH. Overall, the total amount of sequestered CO2 produced by the biokarst system (CaCO3-CO2-microalgae) shows a minimum at a specific pH then increases with decreasing pH. Therefore, various processes and carbon sinks in the biokarst system are sensitive to pH changes, and biokarst processes play an important negative feedback role in the release of CO2 by acidification. The results also suggest that the carbon sink associated with carbonate weathering cannot be neglected when considering the global carbon cycle on the scale of thousands of years (<3 ka).

Low-Temperature Plasma Functionalization of Carbon Nanotubes

NASA Technical Reports Server (NTRS)

Khare, Bishun; Meyyappan, M.

2004-01-01

A low-temperature plasma process has been devised for attaching specified molecular groups to carbon nanotubes in order to impart desired chemical and/or physical properties to the nanotubes for specific applications. Unlike carbon-nanotube- functionalization processes reported heretofore, this process does not involve the use of wet chemicals, does not involve exposure of the nanotubes to high temperatures, and generates very little chemical residue. In addition, this process can be carried out in a relatively simple apparatus and can readily be scaled up to mass production.

Production of granular activated carbon from food-processing wastes (walnut shells and jujube seeds) and its adsorptive properties.

PubMed

Bae, Wookeun; Kim, Jongho; Chung, Jinwook

2014-08-01

Commercial activated carbon is a highly effective absorbent that can be used to remove micropollutants from water. As a result, the demand for activated carbon is increasing. In this study, we investigated the optimum manufacturing conditions for producing activated carbon from ligneous wastes generated from food processing. Jujube seeds and walnut shells were selected as raw materials. Carbonization and steam activation were performed in a fixed-bed laboratory electric furnace. To obtain the highest iodine number, the optimum conditions for producing activated carbon from jujube seeds and walnut shells were 2 hr and 1.5 hr (carbonization at 700 degrees C) followed by 1 hr and 0.5 hr (activation at 1000 degrees C), respectively. The surface area and iodine number of activated carbon made from jujube seeds and walnut shells were 1,477 and 1,184 m2/g and 1,450 and 1,200 mg/g, respectively. A pore-distribution analysis revealed that most pores had a pore diameter within or around 30-40 angstroms, and adsorption capacity for surfactants was about 2 times larger than the commercial activated carbon, indicating that waste-based activated carbon can be used as alternative. Implications: Wastes discharged from agricultural and food industries results in a serious environmental problem. A method is proposed to convert food-processing wastes such as jujube seeds and walnut shells into high-grade granular activated carbon. Especially, the performance of jujube seeds as activated carbon is worthy of close attention. There is little research about the application ofjujube seeds. Also, when compared to two commercial carbons (Samchully and Calgon samples), the results show that it is possible to produce high-quality carbon, particularly from jujube seed, using a one-stage, 1,000 degrees C, steam pyrolysis. The preparation of activated carbon from food-processing wastes could increase economic return and reduce pollution.

Variability in organic carbon reactivity across lake residence time and trophic gradients

NASA Astrophysics Data System (ADS)

Evans, Chris D.; Futter, Martyn N.; Moldan, Filip; Valinia, Salar; Frogbrook, Zoe; Kothawala, Dolly N.

2017-11-01

The transport of dissolved organic carbon from land to ocean is a large dynamic component of the global carbon cycle. Inland waters are hotspots for organic matter turnover, via both biological and photochemical processes, and mediate carbon transfer between land, oceans and atmosphere. However, predicting dissolved organic carbon reactivity remains problematic. Here we present in situ dissolved organic carbon budget data from 82 predominantly European and North American water bodies with varying nutrient concentrations and water residence times ranging from one week to 700 years. We find that trophic status strongly regulates whether water bodies act as net dissolved organic carbon sources or sinks, and that rates of both dissolved organic carbon production and consumption can be predicted from water residence time. Our results suggest a dominant role of rapid light-driven removal in water bodies with a short water residence time, whereas in water bodies with longer residence times, slower biotic production and consumption processes are dominant and counterbalance one another. Eutrophication caused lakes to transition from sinks to sources of dissolved organic carbon. We conclude that rates and locations of dissolved organic carbon processing and associated CO2 emissions in inland waters may be misrepresented in global carbon budgets if temporal and spatial reactivity gradients are not accounted for.

Sensitivity of chemical weathering and dissolved carbon dynamics to hydrological conditions in a typical karst river

PubMed Central

Zhong, Jun; Li, Si-liang; Tao, Faxiang; Yue, Fujun; Liu, Cong-Qiang

2017-01-01

To better understand the mechanisms that hydrological conditions control chemical weathering and carbon dynamics in the large rivers, we investigated hydrochemistry and carbon isotopic compositions of dissolved inorganic carbon (DIC) based on high-frequency sampling in the Wujiang River draining the carbonate area in southwestern China. Concentrations of major dissolved solute do not strictly follow the dilution process with increasing discharge, and biogeochemical processes lead to variability in the concentration-discharge relationships. Temporal variations of dissolved solutes are closely related to weathering characteristics and hydrological conditions in the rainy seasons. The concentrations of dissolved carbon and the carbon isotopic compositions vary with discharge changes, suggesting that hydrological conditions and biogeochemical processes control dissolved carbon dynamics. Biological CO2 discharge and intense carbonate weathering by soil CO2 should be responsible for the carbon variability under various hydrological conditions during the high-flow season. The concentration of DICbio (DIC from biological sources) derived from a mixing model increases with increasing discharge, indicating that DICbio influx is the main driver of the chemostatic behaviors of riverine DIC in this typical karst river. The study highlights the sensitivity of chemical weathering and carbon dynamics to hydrological conditions in the riverine system. PMID:28220859

Evaluation of the genotoxicity of waters impacted by domestic and industrial effluents of a highly industrialized region of São Paulo State, Brazil, by the comet assay in HTC cells.

PubMed

Manzano, Bárbara Cassu; Roberto, Matheus Mantuanelli; Hoshina, Márcia Miyuki; Menegário, Amauri Antônio; Marin-Morales, Maria Aparecida

2015-01-01

The problems that most affect the quality of the waters of rivers and lakes are associated with the discharges performed in these environments, mainly industrial and domestic effluents inappropriately treated or untreated. The comet assay is a sensitive tool and is recommended for studies of environmental biomonitoring, which aim to determine the genotoxicity potential of water pollutants. This study aimed to assess the genotoxic potential of the Ribeirão Tatu waters, region of Limeira, São Paulo (SP), by the comet assay with mammalian cells (hepatoma tissue culture (HTC)). Water samples were collected along the Ribeirão Tatu at three distinct periods: November 2008, February 2009 and August 2009, and five collection sites were established: P1, source of the stream; P2, site located downstream the urban perimeter of the municipality of Cordeirópolis and after receiving the pollution load of this city; P3, collection site located upstream the urban perimeter of the city of Limeira; P4, urban area of Limeira; and P5, rural area of Limeira, downstream the discharges of the city sewage. The results showed that for the November 2008 collection, there was no water sample-induced genotoxicity; for the February 2009 collection, the sites P1 and P2 were statistically significant in relation to the negative control (NC), and for the August 2009 collection, the site P5 was statistically significant. These results could be explained by the content of different metals during the different seasons that are under the influence of domestic, industrial and agricultural effluents and also due to the seasonality, since the water samples collected in the period of heavy rain (February 2009) presented a higher genotoxicity possibly due to the entrainment of contaminants into the bed of the stream promoted by the outflow of rainwaters. The comet assay showed to be a useful and sensitive tool in the evaluation of hydric resources impacted by pollutants of diverse origins, and a constant monitoring should be done in order to verify the influence of different factors (season, amount of contaminants) in the water quality.

'It is just the way it was in the past before I went to test': a qualitative study to explore responses to HIV prevention counselling in rural Tanzania.

PubMed

Cawley, Caoimhe; Wringe, Alison; Wamoyi, Joyce; Lees, Shelley; Urassa, Mark

2016-06-08

Voluntary counselling and testing (VCT) for HIV first evolved in Western settings, with one aim being to promote behaviours which lower the risk of onward transmission or acquisition of HIV. However, although quantitative studies have shown that the impact of VCT on sexual behaviour change has been limited in African settings, there is a lack of qualitative research exploring perceptions of HIV prevention counselling messages, particularly among clients testing HIV-negative. We conducted a qualitative study to explore healthcare worker, community and both HIV-negative and HIV-positive clients' perceptions of HIV prevention counselling messages in rural Tanzania. This study was carried out within the context of an ongoing community HIV cohort study in Kisesa, northwest Tanzania. Nine group sessions incorporating participatory learning and action (PLA) activities were conducted in order to gain general community perspectives of HIV testing and counselling (HTC) services. Thirty in-depth interviews (IDIs) with HIV-negative and HIV-positive service users explored individual perceptions of HIV prevention counselling messages, while five IDIs were carried out with nurses or counsellors offering HTC in order to explore provider perspectives. Two key themes revolving around socio-cultural and contextual factors emerged in understanding responses to HIV prevention counselling messages. The first included constraints to client-counsellor interactions, which were impeded as a result of difficulties discussing private sexual behaviours during counselling sessions, a hierarchical relationship between healthcare providers and clients, insufficient levels of training and support for counsellors, and client concerns about confidentiality. The second theme related to imbalanced gender-power dynamics, which constrained the extent to which women felt able to control their HIV-related risk. Within the broader social context of a rural African setting, HIV prevention counselling based on a Western model of individual-level agency seems unlikely to make a significant contribution to sexual behaviour change until there is greater recognition by counsellors of the ways in which power dynamics within many relationships influence behaviour change. More culturally relevant counselling strategies and messages and infrastructural improvements such as additional training for counsellors and counselling rooms which ensure privacy and confidentiality, may lead to better outcomes in terms of sexual risk reduction.

Immunological responses and disease resistance of rainbow trout (Oncorhynchus mykiss) juveniles following dietary administration of stinging nettle (Urtica dioica).

PubMed

Saeidi Asl, Mohammad Reza; Adel, Milad; Caipang, Christopher Marlowe A; Dawood, Mahmoud A O

2017-12-01

The present study investigated the effects of dietary supplementation of stinging nettle (Urtica dioica) on growth performance, skin mucus, immune response and disease resistance of rainbow trout (Oncorhynchus mykiss) fed with diets supplemented with U. dioica at 0, 1, 2 and 3%. After 8 weeks of feeding, the addition of U. dioica at 3% level resulted in improved weight gain, specific growth rate and feed conversion ratio significantly when compared to the other groups (P < 0.05). Hematological responses including: hematocrit (Htc), hemoglobin (Hb), lymphocyte and neutrophil populations enhanced significantly in fish fed 3% of stinging nettle when measured after 4 weeks; while, total red blood cells, white blood, Htc, Hb, lymphocyte and neutrophil populations significantly increased after 8 weeks in the same group (P < 0.05). Total serum protein and glucose contents increased significantly in fish fed stinging nettle at 3% when compared to the other groups after 8 weeks; however, triglycerides decreased significantly in the same group on the 4th and 8th week (P < 0.05). Additionally, several immune parameters, namely, IgM, lysozyme, complement components C3 and C4, and respiratory burst of blood leukocytes significantly increased in the 3% fed group on the 4th week; while, after 8 weeks the immune responses enhanced in fish fed 2 and 3% diets (P < 0.05). At the end of the feeding trial, mucus samples obtained from the fish fed stinging nettle supplementation exhibited improved antagonistic activities against several bacterial pathogens (Streptococcus iniae, Yersinia ruckeri, Vibrio anguillarum and Lactococcus garviae), skin mucus enzymes activities (alkaline phosphatase, lysozyme, protease and esterase) and protein levels in 2 and 3% groups with the highest being in case of 3% group when compared to the other groups (P < 0.05). The cumulative mortality of rainbow trout subjected to Y. ruckeri infectious exhibited relatively low mortality levels in all supplemented groups with the lowest being in fish fed 3% stinging nettle. The present findings demonstrated that dietary administration of U. dioica enhanced growth and stimulated fish immunity; thus, enabling the fish to be more resistant against bacterial infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

Towards elimination of mother-to-child transmission of HIV: performance of different models of care for initiating lifelong antiretroviral therapy for pregnant women in Malawi (Option B+).

PubMed

van Lettow, Monique; Bedell, Richard; Mayuni, Isabell; Mateyu, Gabriel; Landes, Megan; Chan, Adrienne K; van Schoor, Vanessa; Beyene, Teferi; Harries, Anthony D; Chu, Stephen; Mganga, Andrew; van Oosterhout, Joep J

2014-01-01

Malawi introduced a new strategy to improve the effectiveness of prevention of mother-to-child HIV transmission (PMTCT), the Option B+ strategy. We aimed to (i) describe how Option B+ is provided in health facilities in the South East Zone in Malawi, identifying the diverse approaches to service organization (the "model of care") and (ii) explore associations between the "model of care" and health facility-level uptake and retention rates for pregnant women identified as HIV-positive at antenatal (ANC) clinics. A health facility survey was conducted in all facilities providing PMTCT/antiretroviral therapy (ART) services in six of Malawi's 28 districts to describe and compare Option B+ service delivery models. Associations of identified models with program performance were explored using facility cohort reports. Among 141 health facilities, four "models of care" were identified: A) facilities where newly identified HIV-positive women are initiated and followed on ART at the ANC clinic until delivery; B) facilities where newly identified HIV-positive women receive only the first dose of ART at the ANC clinic, and are referred to the ART clinic for follow-up; C) facilities where newly identified HIV-positive women are referred from ANC to the ART clinic for initiation and follow-up of ART; and D) facilities serving as ART referral sites (not providing ANC). The proportion of women tested for HIV during ANC was highest in facilities applying Model A and lowest in facilities applying Model B. The highest retention rates were reported in Model C and D facilities and lowest in Model B facilities. In multivariable analyses, health facility factors independently associated with uptake of HIV testing and counselling (HTC) in ANC were number of women per HTC counsellor, HIV test kit availability, and the "model of care" applied; factors independently associated with ART retention were district location, patient volume and the "model of care" applied. A large variety exists in the way health facilities have integrated PMTCT Option B+ care into routine service delivery. This study showed that the "model of care" chosen is associated with uptake of HIV testing in ANC and retention in care on ART. Further patient-level research is needed to guide policy recommendations.

Feasibility of a smartphone-based balance assessment system for subjects with chronic stroke.

PubMed

Hou, You-Ruei; Chiu, Ya-Lan; Chiang, Shang-Lin; Chen, Hui-Ya; Sung, Wen-Hsu

2018-07-01

Stroke is a cerebral artery disease that may lead to long-term disabilities or death. Patients that survive a stroke usually suffer balance impairments, which affect their performance in activities of daily living (ADLs) and quality of life (QoL). In recent years, smartphones have become very popular and have many capabilities. Smartphone built-in sensors have shown their ability and potential in balance performance assessment. However, the feasibility of smartphones on subjects with chronic strokes remains to be proved. Therefore, the purpose of this study is to evaluate the feasibility of a smartphone-based balance assessment system for subjects with chronic stroke. Ten subjects with chronic stroke and thirteen healthy adults were recruited in the study. The smartphone HTC 10 (HTC Corporation, Taiwan) was used to perform the balance assessment, and its built-in accelerometer and gyroscope were used to record data from the subjects. Six postures were tested for thirty seconds each: shoulder-width stance (SWS) with eyes opened (E/O) and eyes closed (E/C), feet-together stance (FTS) with E/O and E/C, and semi-tandem stance (STS) with E/O and E/C. The smartphone was fixed to the back of subjects at the second sacral spine (S2) level. The changes registered in the accelerometer and gyroscope data were used to represent the balance performance, in which higher values indicate more instability. Data was analyzed using the independent t-test with the software SPSS 20, and the statistical significance level was set to α < 0.05. Significant difference in the acceleration data was found among subjects with chronic stroke and healthy adults under four assessment postures: SWS with E/C (p = 0.048), FTS with E/O (p = 0.027), FTS with E/C (p = 0.000), and STS with E/C (p = 0.048). Furthermore, according to the gyroscope data, there were significant differences in how the two groups performed the postures. The results demonstrate that a smartphone with a built-in accelerometer and gyroscope can be used to classify balance performances between healthy adults and subjects with chronic stroke. This study shows that smartphones are feasible to assess balance for subjects with chronic stroke. Copyright © 2018 Elsevier B.V. All rights reserved.

Towards elimination of mother-to-child transmission of HIV: performance of different models of care for initiating lifelong antiretroviral therapy for pregnant women in Malawi (Option B+)

PubMed Central

van Lettow, Monique; Bedell, Richard; Mayuni, Isabell; Mateyu, Gabriel; Landes, Megan; Chan, Adrienne K; van Schoor, Vanessa; Beyene, Teferi; Harries, Anthony D; Chu, Stephen; Mganga, Andrew; van Oosterhout, Joep J

2014-01-01

Introduction Malawi introduced a new strategy to improve the effectiveness of prevention of mother-to-child HIV transmission (PMTCT), the Option B+ strategy. We aimed to (i) describe how Option B+ is provided in health facilities in the South East Zone in Malawi, identifying the diverse approaches to service organization (the “model of care”) and (ii) explore associations between the “model of care” and health facility–level uptake and retention rates for pregnant women identified as HIV-positive at antenatal (ANC) clinics. Methods A health facility survey was conducted in all facilities providing PMTCT/antiretroviral therapy (ART) services in six of Malawi's 28 districts to describe and compare Option B+ service delivery models. Associations of identified models with program performance were explored using facility cohort reports. Results Among 141 health facilities, four “models of care” were identified: A) facilities where newly identified HIV-positive women are initiated and followed on ART at the ANC clinic until delivery; B) facilities where newly identified HIV-positive women receive only the first dose of ART at the ANC clinic, and are referred to the ART clinic for follow-up; C) facilities where newly identified HIV-positive women are referred from ANC to the ART clinic for initiation and follow-up of ART; and D) facilities serving as ART referral sites (not providing ANC). The proportion of women tested for HIV during ANC was highest in facilities applying Model A and lowest in facilities applying Model B. The highest retention rates were reported in Model C and D facilities and lowest in Model B facilities. In multivariable analyses, health facility factors independently associated with uptake of HIV testing and counselling (HTC) in ANC were number of women per HTC counsellor, HIV test kit availability, and the “model of care” applied; factors independently associated with ART retention were district location, patient volume and the “model of care” applied. Conclusions A large variety exists in the way health facilities have integrated PMTCT Option B+ care into routine service delivery. This study showed that the “model of care” chosen is associated with uptake of HIV testing in ANC and retention in care on ART. Further patient-level research is needed to guide policy recommendations. PMID:25079437

Sequestration of flue gas CO₂ by direct gas-solid carbonation of air pollution control system residues.

PubMed

Tian, Sicong; Jiang, Jianguo

2012-12-18

Direct gas-solid carbonation reactions of residues from an air pollution control system (APCr) were conducted using different combinations of simulated flue gas to study the impact on CO₂ sequestration. X-ray diffraction analysis of APCr determined the existence of CaClOH, whose maximum theoretical CO₂ sequestration potential of 58.13 g CO₂/kg APCr was calculated by the reference intensity ratio method. The reaction mechanism obeyed a model of a fast kinetics-controlled process followed by a slow product layer diffusion-controlled process. Temperature is the key factor in direct gas-solid carbonation and had a notable influence on both the carbonation conversion and the CO₂ sequestration rate. The optimal CO₂ sequestrating temperature of 395 °C was easily obtained for APCr using a continuous heating experiment. CO₂ content in the flue gas had a definite influence on the CO₂ sequestration rate of the kinetics-controlled process, but almost no influence on the final carbonation conversion. Typical concentrations of SO₂ in the flue gas could not only accelerate the carbonation reaction rate of the product layer diffusion-controlled process, but also could improve the final carbonation conversion. Maximum carbonation conversions of between 68.6% and 77.1% were achieved in a typical flue gas. Features of rapid CO₂ sequestration rate, strong impurities resistance, and high capture conversion for direct gas-solid carbonation were proved in this study, which presents a theoretical foundation for the applied use of this encouraging technology on carbon capture and storage.

[Review of lime carbon sink.

PubMed

Liu, Li Li; Ling, Jiang Hua; Tie, Li; Wang, Jiao Yue; Bing, Long Fei; Xi, Feng Ming

2018-01-01

Under the background of "missing carbon sink" mystery and carbon capture and storage (CCS) technology development, this paper summarized the lime material flow process carbon sink from the lime carbonation principles, impact factors, and lime utilization categories in chemical industry, metallurgy industry, construction industry, and lime kiln ash treatment. The results showed that the lime carbonation rate coefficients were mainly impacted by materials and ambient conditions; the lime carbon sink was mainly in chemical, metallurgy, and construction industries; and current researches focused on the mechanisms and impact factors for carbonation, but their carbon sequestration calculation methods had not been proposed. Therefore, future research should focus on following aspects: to establish a complete system of lime carbon sequestration accounting method in view of material flow; to calculate lime carbon sequestration in both China and the world and explain their offset proportion of CO 2 emission from lime industrial process; to analyze the contribution of lime carbon sequestration to missing carbon sink for clarifying part of missing carbon sinks; to promote the development of carbon capture and storage technology and provide some scientific bases for China's international negotiations on climate change.