Solid oxide fuel cells fueled with reducible oxides

Science.gov (United States)

Chuang, Steven S.; Fan, Liang Shih

2018-01-09

A direct-electrochemical-oxidation fuel cell for generating electrical energy includes a cathode provided with an electrochemical-reduction catalyst that promotes formation of oxygen ions from an oxygen-containing source at the cathode, a solid-state reduced metal, a solid-state anode provided with an electrochemical-oxidation catalyst that promotes direct electrochemical oxidation of the solid-state reduced metal in the presence of the oxygen ions to produce electrical energy, and an electrolyte disposed to transmit the oxygen ions from the cathode to the solid-state anode. A method of operating a solid oxide fuel cell includes providing a direct-electrochemical-oxidation fuel cell comprising a solid-state reduced metal, oxidizing the solid-state reduced metal in the presence of oxygen ions through direct-electrochemical-oxidation to obtain a solid-state reducible metal oxide, and reducing the solid-state reducible metal oxide to obtain the solid-state reduced metal.

Thin Solid Oxide Cell

DEFF Research Database (Denmark)

2010-01-01

The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

Ovarian Stem Cell Nests in Reproduction and Ovarian Aging.

Science.gov (United States)

Ye, Haifeng; Zheng, Tuochen; Li, Wei; Li, Xiaoyan; Fu, Xinxin; Huang, Yaoqi; Hu, Chuan; Li, Jia; Huang, Jian; Liu, Zhengyv; Zheng, Liping; Zheng, Yuehui

2017-01-01

The fixed primordial follicles pool theory, which monopolized reproductive medicine for more than one hundred years, has been broken by the discovery, successful isolation and establishment of ovarian stem cells. It has brought more hope than ever of increasing the size of primordial follicle pool, improving ovarian function and delaying ovarian consenescence. Traditional view holds that stem cell aging contributes to the senility of body and organs. However, in the process of ovarian aging, the main factor leading to the decline of the reproductive function is the aging and degradation of ovarian stem cell nests, rather than the senescence of ovarian germ cells themselves. Recent studies have found that the immune system and circulatory system are involved in the formation of ovarian germline stem cell niches, as well as regulating the proliferation and differentiation of ovarian germline stem cells through cellular and hormonal signals. Therefore, we can improve ovarian function and delay ovarian aging by improving the immune system and circulatory system, which will provide an updated program for the treatment of premature ovarian failure (POF) and infertility. © 2017 The Author(s). Published by S. Karger AG, Basel.

Reproductive potential and nesting effects of Osmia rufa (syn. bicornis female (Hymenoptera: Megachilidae

Directory of Open Access Journals (Sweden)

Giejdasz Karol

2016-06-01

Full Text Available The red mason bee Osmia rufa is a solitary bee belonging to the family Megachilidae, and is prone to nest in aggregations. Each female builds a nest separately in pre-existing cavities such as holes in wood and walls or empty plant stems. This is done by successively setting the cells in a linear series. In this study, we elucidate the nesting behavior and the reproductive potential of a single O. rufa female. The reproductive potential of nesting females was evaluated after the offspring finished development. We observed that an individual female may colonize up to five nest tubes and build 5-34 cells in them (16 on an average. During the nesting time the number of cells decreased with the sequence of nest tubes colonized by one female, which built a maximum of 11 cells in the first occupied nest and 5 cells in the last (fifth nest. Our observations indicated that 40% of nesting females colonized one nest tube as compared to 7% colonizing five nest tubes. Furthermore, in subsequent nest tubes the number of cells with freshly emerged females gradually decreased which was the reverse with males. Thus, the sex ratio (proportion of male and female offspring may change during the nesting period. The female offspring predominated in the first two nesting tubes, while in the subsequent three tubes male offspring dominated. We also cataloged different causes of reduction in abundance of offspring in O. rufa females such as parasitization or problem associated with moulting.

Nesting biology of Trypoxylon (Trypargilum) lactitarse Saussure (Hymenoptera, Crabronidae) in trap-nests in Southern Brazil.

Science.gov (United States)

Buschini, M L T; Niesing, F; Wolff, L L

2006-08-01

This study was carried in the Parque Municipal das Araucárias in the municipality of Guarapuava, state of Paraná, Southern Brazil. Three hundred and sixty five nests of T. lactitarse were obtained using trap-nests of 0.7, 1.0, and 1.3 cm in diameter. All of them had similar architecture, regardless of the diameter of the trap-nest. Completed nests consisted of a linear series of brood cells whose average number per nest was of 3.3, 4.0 and 3.6 for the nests with 0.7 cm, 1.0 cm and 1.3 cm in diameter, respectively. They were constructed more often during the summer. T. lactitarse had two types of life cycles: direct development (without diapause), and delayed development (with diapause during winter). Natural enemies included Chrysididae, Sarcophagidae, Dolichopodidae and Ichneumonidae. Out of 1,353 identified spider prey, 1,313 belonged to the Araneidae family.

Nesting biology of Trypoxylon (Trypargilum lactitarse Saussure (Hymenoptera, Crabronidae in trap-nests in Southern Brazil

Directory of Open Access Journals (Sweden)

M. L. T. Buschini

Full Text Available This study was carried in the Parque Municipal das Araucárias in the municipality of Guarapuava, state of Paraná, Southern Brazil. Three hundred and sixty five nests of T. lactitarse were obtained using trap-nests of 0.7, 1.0, and 1.3 cm in diameter. All of them had similar architecture, regardless of the diameter of the trap-nest. Completed nests consisted of a linear series of brood cells whose average number per nest was of 3.3, 4.0 and 3.6 for the nests with 0.7 cm, 1.0 cm and 1.3 cm in diameter, respectively. They were constructed more often during the summer. T. lactitarse had two types of life cycles: direct development (without diapause, and delayed development (with diapause during winter. Natural enemies included Chrysididae, Sarcophagidae, Dolichopodidae and Ichneumonidae. Out of 1,353 identified spider prey, 1,313 belonged to the Araneidae family.

SOLID STATE ENERGY CONVERSION ALLIANCE (SECA) SOLID OXIDE FUEL CELL PROGRAM

Energy Technology Data Exchange (ETDEWEB)

Nguyen Minh; Jim Powers

2003-10-01

This report summarizes the work performed for April 2003--September 2003 reporting period under Cooperative Agreement DE-FC26-01NT41245 for the U.S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid State Energy Conversion Alliance (SECA) Solid oxide Fuel Cell Program''. During this reporting period, the conceptual system design activity was completed. The system design, including strategies for startup, normal operation and shutdown, was defined. Sealant and stack materials for the solid oxide fuel cell (SOFC) stack were identified which are capable of meeting the thermal cycling and degradation requirements. A cell module was tested which achieved a stable performance of 0.238 W/cm{sup 2} at 95% fuel utilization. The external fuel processor design was completed and fabrication begun. Several other advances were made on various aspects of the SOFC system, which are detailed in this report.

The importance of illumination in nest site choice and nest characteristics of cavity nesting birds.

Science.gov (United States)

Podkowa, Paweł; Surmacki, Adrian

2017-05-02

Light has a significant impact on many aspects of avian biology, physiology and behaviour. An increasing number of studies show that illumination may positively influences birds' offspring fitness by e.g. acceleration of embryo development, stimulation of skeleton growth or regulation of circadian rhythm. Because nest cavities have especially low illumination, suitable light levels may be especially important for species which nest there. We may therefore expect that birds breeding in relatively dim conditions should prefer brighter nest sites and/or evolve behavioral mechanisms to secure sufficient light levels in the nest. Using nest boxes with modified internal illumination, we experimentally tested whether light regime is a cue for nest site selection of secondary cavity-nesting species. Additionally, we investigated whether nest building strategies are tuned to internal illumination. Our results demonstrate that, nest boxes with elevated illumination were chosen twice as often as dark nest boxes. Moreover, birds built higher nests in dark nest boxes than birds in boxes with elevated illumination, which suggests a mechanism of compensating for low light conditions. Our results provide the first experimental support for the idea that nest site choice and nest building behaviour in cavity-nesting birds are influenced by ambient illumination.

Bee species-specific nesting material attracts a generalist parasitoid: implications for co-occurring bees in nest box enhancements.

Science.gov (United States)

Macivor, J Scott; Salehi, Baharak

2014-08-01

Artificial nests (e.g., nest boxes) for bees are increasingly being used to contribute to nesting habitat enhancement for bees that use preexisting cavities to provision brood. They usually incorporate additional nesting materials that vary by species. Cavity-nesting bees are susceptible to brood parasitoids that recognize their host(s) using visual and chemical cues. Understanding the range of cues that attract parasitoids to bee nests, including human-made analogues, is important if we wish to control parasitism and increase the potential value of artificial nests as habitat-enhancement strategies. In this study, we investigated the cues associated with the orientation of the generalist brood parasitoid Monodontomerus obscurus Westwood (Hymenoptera: Torymidae) to the nests of a common cavity-nesting resin bee Megachile campanulae (Robertson) (Megachilidae). The parasitoids were reared from previously infested M. campanulae brood cells and placed into choice trials where they were presented with pairs of different nest material cues. Among different materials tested, we found that Mo. obscurus was most attracted to fresh resin collected directly from Pinus strobus trees followed by previously used resin collected from the bee nest. The parasitoid also attacked other bee species in the same nest boxes, including those that do not use resin for nesting. Our findings suggest that M. campanulae could act as a magnet, drawing parasites away from other bee hosts co-occurring in nest boxes, or, as an attractant of Mo. obscurus to nest boxes, increasing attacks on co-occurring host bee species, potentially undermining bee diversity enhancement initiatives.

Degradation in Solid Oxide Cells During High Temperature Electrolysis

Energy Technology Data Exchange (ETDEWEB)

Manohar Sohal

2009-05-01

Idaho National Laboratory has an ongoing project to generate hydrogen from steam using solid oxide electrolysis cells. One goal of that project is to address the technical and degradation issues associated with solid oxide electrolysis cells. This report covers a variety of these degradation issues, which were discussed during a workshop on “Degradation in Solid Oxide Electrolysis Cells and Strategies for its Mitigation,” held in Phoenix, AZ on October 27, 2008. Three major degradation issues related to solid oxide electrolysis cells discussed at the workshop are: • Delamination of O2-electrode and bond layer on steam/O2-electrode side • Contaminants (Ni, Cr, Si, etc.) on reaction sites (triple-phase boundary) • Loss of electrical/ionic conductivity of electrolyte. This list is not all inclusive, but the workshop summary can be useful in providing a direction for future research related to the degradation of solid oxide electrolysis cells.

Advanced methods of solid oxide fuel cell modeling

CERN Document Server

Milewski, Jaroslaw; Santarelli, Massimo; Leone, Pierluigi

2011-01-01

Fuel cells are widely regarded as the future of the power and transportation industries. Intensive research in this area now requires new methods of fuel cell operation modeling and cell design. Typical mathematical models are based on the physical process description of fuel cells and require a detailed knowledge of the microscopic properties that govern both chemical and electrochemical reactions. ""Advanced Methods of Solid Oxide Fuel Cell Modeling"" proposes the alternative methodology of generalized artificial neural networks (ANN) solid oxide fuel cell (SOFC) modeling. ""Advanced Methods

Observations on the Nesting and Prey of the Solitary Wasp, Tachysphex inconspicuus, with a Review of Nesting Behavior in the T. obscuripennis species group

Science.gov (United States)

Kurczewski, Frank E.; Coville, Rollin E.; Schal, Coby

2010-01-01

The nesting behaviors of 10 females of Tachysphex inconspicuus (Kirby) (Hymenoptera: Crabronidae) were studied on a sandy, mowed lawn at the La Selva Biological Station in northeastern Costa Rica on 27–29 April 1980. Twenty-four completed nests were observed, excavated, and measured. The nests had oblique, short burrows leading to one or two shallow cells. Prey cockroaches belonging to 11 species of Chorisoneura and Riatia fulgida (Saussure) (Blattaria: Blattellidae), all tropical wet forest canopy indicator species, were removed from the cells, weighed, and identified. The cockroaches consisted mainly of adult females, selectively preyed upon over adult males and nymphs due to their larger sizes. The aggregate prey mass in cells was separable into prospective larger (heavier) female and smaller (lighter) male cells. Wasps usually oviposited on the heaviest cockroach in a cell, in most cases an adult female. Atypical genus behavior included (1) prey being carried to one side of the wasp and perhaps grasped by a hindleg during removal of the temporary entrance closure and nest entry and (2) wasp's egg being laid affixed to a forecoxal corium and extending backward in a longitudinally posteriad position across the prey's ventral thorax. A comparison with the nesting behavior of other species in the Tachysphex obscuripennis species group is made. PMID:21062142

Enclosed nests may provide greater thermal than nest predation benefits compared with open nests across latitudes

Science.gov (United States)

Martin, Thomas E.; Boyce, Andy J.; Fierro-Calderon, Karolina; Mitchell, Adam E.; Armstad, Connor E.; Mouton, James C.; Bin Soudi, Evertius E.

2017-01-01

Nest structure is thought to provide benefits that have fitness consequences for several taxa. Traditionally, reduced nest predation has been considered the primary benefit underlying evolution of nest structure, whereas thermal benefits have been considered a secondary or even non-existent factor. Yet, the relative roles of these factors on nest structures remain largely unexplored.Enclosed nests have a constructed or natural roof connected to sides that allow a restricted opening or tube entrance that provides cover in all directions except the entrance, whereas open nests are cups or platforms that are open above. We show that construction of enclosed nests is more common among songbirds (Passeriformes) in tropical and southern hemisphere regions than in north temperate regions. This geographic pattern may reflect selection from predation risk, under long-standing assumptions that nest predation rates are higher in southern regions and that enclosed nests reduce predation risk compared with open cup nests. We therefore compared nest predation rates between enclosed vs. open nests in 114 songbird species that do not nest in tree holes among five communities of coexisting birds, and for 205 non-hole-nesting species from the literature, across northern temperate, tropical, and southern hemisphere regions.Among coexisting species, enclosed nests had lower nest predation rates than open nests in two south temperate sites, but not in either of two tropical sites or a north temperate site. Nest predation did not differ between nest types at any latitude based on literature data. Among 319 species from both our field studies and the literature, enclosed nests did not show consistent benefits of reduced predation and, in fact, predation was not consistently higher in the tropics, contrary to long-standing perspectives.Thermal benefits of enclosed nests were indicated based on three indirect results. First, species that built enclosed nests were smaller than species using

A development of solid oxide fuel cell technology

Energy Technology Data Exchange (ETDEWEB)

Lim, Hee Chun; Lee, Chang Woo [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center; Kim, Kwy Youl; Yoon, Moon Soo; Kim, Ho Ki; Kim, Young Sik; Mun, Sung In; Eom, Sung Wuk [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)

1996-12-31

Solid oxide fuel cell which was consisted of ceramics has high power density and is very simple in shape. The project named A development of SOFC(Solid Oxide Fuel Cell) technology is to develop the unit cell fabrication processing and to evaluate the unit cell of solid oxide full cell. In this project, a manufacturing process of cathode by citrate method and polymeric precursor methods were established. By using tape casting method, high density thin electrolyte was manufactured and has high performance. Unit cell composed with La{sub 17}Sr{sub 13}Mn{sub 3} as cathode, 8YSZ electrolyte and 50% NiYSZ anode had a performance of O.85 W/cm{sup 2} and recorded 510 hours operation time. On the basis of these results. 100 cm{sup 2} class unit cell will be fabricated and tests in next program (author). 59 refs., 120 figs.

A development of solid oxide fuel cell technology

Energy Technology Data Exchange (ETDEWEB)

Lim, Hee Chun; Lee, Chang Woo [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center; Kim, Kwy Youl; Yoon, Moon Soo; Kim, Ho Ki; Kim, Young Sik; Mun, Sung In; Eom, Sung Wuk [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)

1995-12-31

Solid oxide fuel cell which was consisted of ceramics has high power density and is very simple in shape. The project named A development of SOFC(Solid Oxide Fuel Cell) technology is to develop the unit cell fabrication processing and to evaluate the unit cell of solid oxide full cell. In this project, a manufacturing process of cathode by citrate method and polymeric precursor methods were established. By using tape casting method, high density thin electrolyte was manufactured and has high performance. Unit cell composed with La{sub 17}Sr{sub 13}Mn{sub 3} as cathode, 8YSZ electrolyte and 50% NiYSZ anode had a performance of O.85 W/cm{sup 2} and recorded 510 hours operation time. On the basis of these results. 100 cm{sup 2} class unit cell will be fabricated and tests in next program (author). 59 refs., 120 figs.

SOLID STATE ENERGY CONVERSION ALLIANCE (SECA) SOLID OXIDE FUEL CELL PROGRAM

Energy Technology Data Exchange (ETDEWEB)

Unknown

2003-06-01

This report summarizes the progress made during the September 2001-March 2002 reporting period under Cooperative Agreement DE-FC26-01NT41245 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program''. The program focuses on the development of a low-cost, high-performance 3-to-10-kW solid oxide fuel cell (SOFC) system suitable for a broad spectrum of power-generation applications. The overall objective of the program is to demonstrate a modular SOFC system that can be configured to create highly efficient, cost-competitive, and environmentally benign power plants tailored to specific markets. When fully developed, the system will meet the efficiency, performance, life, and cost goals for future commercial power plants.

Compiling the parallel programming language NestStep to the CELL processor

OpenAIRE

Holm, Magnus

2010-01-01

The goal of this project is to create a source-to-source compiler which will translate NestStep code to C code. The compiler's job is to replace NestStep constructs with a series of function calls to the NestStep runtime system. NestStep is a parallel programming language extension based on the BSP model. It adds constructs for parallel programming on top of an imperative programming language. For this project, only constructs extending the C language are relevant. The output code will compil...

Solid Oxide Fuel Cell

DEFF Research Database (Denmark)

2010-01-01

The solid oxide fuel cell comprising a metallic support material, an active anode layer consisting of a good hydrocarbon cracking catalyst, an electrolyte layer, an active cathode layer, and a transition layer consisting of preferably a mixture of LSM and a ferrite to the cathode current collector...

Multifemale nests and social behavior in Euglossa melanotricha (Hymenoptera, Apidae, Euglossini

Directory of Open Access Journals (Sweden)

Aline Andrade-Silva

2012-05-01

Full Text Available The nesting biology and social behavior of the euglossine bee species Euglossa melanotricha was analyzed based on the monitoring of eight nests found in man-made cavities and transferred to observation boxes. Euglossa melanotricha females usually construct their nests in cavities in the ground, in buildings, or in mounds. In this study, we present new data on the nesting biology of E. melanotricha. The process of reactivation of nests was commonly observed with one to three females participating in the reactivation. The duration of the process of reactivation ranged from 10 to 78 days (n = 31 and were longer during the rainy season. Time spent (in days for provisioning, oviposition and closing a single cell was higher in reactivations that occurred during the dry period.151 emergences were observed (39 males and 112 females. 90 (80.3% of the emerged females returned to the natal nest, but only 35 (38.9% remained and actively participated in the construction and provisioning of cells. The other 55 abandoned the nests after several days without performing any work in the nest. Matrifilial nest structure was regulated by dominance-subordinate aggressive behavior among females, where the dominant female laid almost all eggs. Task allocation was recognized by behavioral characteristics, namely, agonism and oophagy in cells oviposited by other females. Euglossa melanotricha is multivoltine and its nesting is asynchronous with respect to season. Our observations suggest a primitively eusocial organization. These observations of E. melanotricha provide valuable information for comparison with other species of Euglossa in an evolutionary context.

Influence of olfactory and visual cover on nest site selection and nest success for grassland-nesting birds.

Science.gov (United States)

Fogarty, Dillon T; Elmore, R Dwayne; Fuhlendorf, Samuel D; Loss, Scott R

2017-08-01

Habitat selection by animals is influenced by and mitigates the effects of predation and environmental extremes. For birds, nest site selection is crucial to offspring production because nests are exposed to extreme weather and predation pressure. Predators that forage using olfaction often dominate nest predator communities; therefore, factors that influence olfactory detection (e.g., airflow and weather variables, including turbulence and moisture) should influence nest site selection and survival. However, few studies have assessed the importance of olfactory cover for habitat selection and survival. We assessed whether ground-nesting birds select nest sites based on visual and/or olfactory cover. Additionally, we assessed the importance of visual cover and airflow and weather variables associated with olfactory cover in influencing nest survival. In managed grasslands in Oklahoma, USA, we monitored nests of Northern Bobwhite ( Colinus virginianus ), Eastern Meadowlark ( Sturnella magna ), and Grasshopper Sparrow ( Ammodramus savannarum ) during 2015 and 2016. To assess nest site selection, we compared cover variables between nests and random points. To assess factors influencing nest survival, we used visual cover and olfactory-related measurements (i.e., airflow and weather variables) to model daily nest survival. For nest site selection, nest sites had greater overhead visual cover than random points, but no other significant differences were found. Weather variables hypothesized to influence olfactory detection, specifically precipitation and relative humidity, were the best predictors of and were positively related to daily nest survival. Selection for overhead cover likely contributed to mitigation of thermal extremes and possibly reduced detectability of nests. For daily nest survival, we hypothesize that major nest predators focused on prey other than the monitored species' nests during high moisture conditions, thus increasing nest survival on these

Nesting biology of Centris (Centris aenea Lepeletier (Hymenoptera, Apidae, Centridini

Directory of Open Access Journals (Sweden)

Cândida Maria Lima Aguiar

2003-12-01

Full Text Available Nesting activity of Centris aenea Lepeletier, 1841 was studied in two Brazilian habitats, Caatinga (Monte Santo, Bahia and Cerrado (Palmeiras, Bahia and Luiz Antônio, São Paulo. Nests were excavated in the ground and did not tend to be aggregated together at the two sites, but at Palmeiras, nests were in a large aggregation. Nest architecture consists of a single unbranched tunnel, sloping to vertical, which leads to a linear series of four cells, placed from 8 to 26 cm in depth. Cells are urn-shaped with a rounded base, and their cell caps have a central hollow process, as in other Centridini. Nest architecture of C. aenea was compared to other species of Centris Fabricius, 1804. Provisions are composed of a pollen mass covered by a thin liquid layer on which the egg is placed. Females were observed gathering oil on Mcvaughia bahiana W.R. Anderson flowers from October to March in the Caatinga, and on Byrsonima intermedia A.Juss. as well as other Malpighiaceae species from August to December in the Cerrado. Pollen is gathered by buzzing flowers of Solanaceae, Caesalpiniaceae, Malpighiaceae, and Ochnaceae. Several nectar sources were recorded. There is indirect evidence that Mesoplia sp. parasitizes nests of C. aenea in the Cerrado.

The cavity-nest ant Temnothorax crassispinus prefers larger nests.

Science.gov (United States)

Mitrus, S

Colonies of the ant Temnothorax crassispinus inhabit mostly cavities in wood and hollow acorns. Typically in the field, nest sites that can be used by the ant are a limited resource. In a field experiment, it was investigated whether the ants prefer a specific size of nest, when different ones are available. In July 2011, a total of 160 artificial nests were placed in a beech-pine forest. Four artificial nests (pieces of wood with volume cavities, ca 415, 605, 730, and 980 mm 3 , respectively) were located on each square meter of the experimental plot. One year later, shortly before the emergence of new sexuals, the nests were collected. In July 2012, colonies inhabited more frequently bigger nests. Among queenright colonies, the ones which inhabited bigger nests had more workers. However, there was no relationship between volume of nest and number of workers for queenless colonies. Queenright colonies from bigger nests produced more sexual individuals, but there was no correlation between number of workers and sex allocation ratio, or between volume of nest and sex allocation ratio. In a laboratory experiment where ant colonies were kept in 470 and 860 mm 3 nests, larger colonies allocated more energy to produce sexual individuals. The results of this study show the selectivity of T. crassispinus ants regarding the size of nest cavity, and that the nest volume has an impact on life history parameters.

The nested variant of bladder transitional cell carcinoma: Review of 12 cases and review of the literature.

Science.gov (United States)

Carrion-Ballardo, C J; Gala-Solana, L; Portillo-Martin, J A; Azueta-Etxebarria, A; Truan-Cacho, D; Campos-Juanatey, F

2015-01-01

The nested variant of bladder transitional cell carcinoma is extremely rare and has a different biological behavior to other bladder tumors. The aim of this study is to analize if their behavior is as aggressive as has been described in the literature. Review of 12 diagnosed cases with nested variant of bladder transitional cell carcinoma and analysis of demographic characteristics, clinical presentation, tumor characteristics, treatment options, analysis of recurrence and cancer-specific survival between January 1997 and December 2010 in our hospital. 50% of the cases had a pathologic stage ≥T2, with grade of differentiation G2 (50%) or G3 (50%). After the pathological result of the TUR (transurethral resection) Bladder, 5 cases underwent radical cystoprostatectomy, 3 a second TUR bladder and 4 cases with treatment chemotherapy and/or radiotherapy (RT). Five out of 12 cases (41.7%) died due to bladder cancer and 3 died (25%) of other causes (urinary sepsis, respiratory failure, renal failure). With a median follow up of 40 months, the overall survival was 50% and cancer-specific survival of 65.6%. The nested variant of bladder transitional cell carcinoma is a disease with an advanced-stage presentation, with high recurrence and mortality rates despite the use of different treatments. So far there is not a clinical practice guideline for this variety of urothelial tumor. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Materials for high temperature solid oxide fuel cells

International Nuclear Information System (INIS)

Singhal, S.C.

1987-01-01

High temperature solid oxide fuel cells show great promise for economical production of electricity. These cells are based upon the ability of stabilized zirconia to operate as an oxygen ion conductor at elevated temperatures. The design of the tubular solid oxide fuel cell being pursued at Westinghouse is illustrated. The cell uses a calcia-stabilized zironcia porous support tube, which acts both as a structural member onto which the other cell components are fabricated in the form of thin layers, and as a functional member to allow the passage, via its porosity, of air (or oxygen) to the air electrode. This paper summarizes the materials and fabrication processes for the various cell components

Diagnosis of lymphoma in paraffin wax sections by nested PCR and immunohistochemistry.

OpenAIRE

Kitamura, Y; Nanba, E; Inui, S; Tanigawa, T; Ichihara, K

1996-01-01

AIMS: To investigate whether nested polymerase chain reaction (PCR) and immunohistochemistry can be used to diagnose malignant lymphoma. METHODS: Paraffin wax embedded tissue sections from 31 patients with malignant lymphoma were analysed by nested PCR and immunohistochemistry using standard protocols. RESULTS: Nested PCR amplification of 1 pg DNA confirmed monoclonality in B cell lymphoma; PCR amplification of 10 pg DNA confirmed monoclonality in T cell lymphoma. Twenty seven (87%) samples w...

The influence of nest-site characteristics on the nesting success of ...

African Journals Online (AJOL)

Choice of nest site has important consequences for nest survival. We examined nest-site characteristics relative to nest success in Karoo Prinias breeding in coastal dwarf shrubland, where high nest predation is the main cause of nest failure. Initially, we compared nests that failed during the building, laying, incubation and ...

Electrode Kinetics and Gas Conversion in Solid Oxide Cells

DEFF Research Database (Denmark)

Njodzefon, Jean-Claude

The solid oxide fuel cell (SOFC) converts hydrogen, carbon monoxide and hydrocarbon fuels (directly) into electricity with very high efficiencies and has demonstrated almost comparable performance when operated in reverse mode as a solid oxide electrolysis cell (SOEC). In this case electrical (and...... thermal) energy is stored as chemical energy of reaction products. To this end, the cells are fed with steam (H2O electrolysis), carbon dioxide (CO2 electrolysis) or a mixture of both (H2O/CO2 co-electrolysis) and of course electrical (ΔG) and thermal (TΔS) energies for the splitting of reactant compounds...... of the solid oxide cell (SOC) and independent of polarization mode (fuel cell mode or electrolysis mode), the current flowing through the cell is limited by processes such as adsorption and desorption of reactants or products, diffusion through the porous electrodes, activation or charge transfer...

Do weather conditions correlate with findings in failed, provision-filled nest cells of Megachile rotundata (Hymenoptera: Megachilidae) in western North America?

Science.gov (United States)

Pitts-Singer, Theresa L; James, Rosalind R

2008-06-01

Cavity-nesting alfalfa leafcutting bees, Megachile rotundata (F.) (Hymenoptera: Megachilidae), are excellent pollinators of alfalfa, Medicago savita L., for seed production. In commercial settings, artificial cavities are placed in field domiciles for nesting and, thereby, bee populations are sustained for future use. For this study, cells from leafcutting bee nests were collected in late summer from commercial seed fields. Over 3 yr (2003-2005), 39 samples in total of approximately equal to 1,000 cells each were taken from several northwestern U.S. states and from Manitoba, Canada. X-radiography of 500 cells from each sample was used to identify "pollen balls" (i.e., cells in which the pollen-nectar provision remained, but the egg or larva, if present, was not detectable on an x-radiograph). Most U.S. samples seemed to have higher proportions of pollen ball cells than Manitoba samples. Pollen ball cells were dissected to determine the moisture condition of the mass provision and true contents of each cell. Most pollen ball cells from Manitoba samples contained fungus, the frequency of which was positively correlated with cool, wet weather. In the United States, most pollen ball cells had moist provisions, and many of them lacked young brood. Correlation analysis revealed that pollen ball cells occurred in greater proportions in fields with more hot days (above 38 degrees C). Broodless pollen ball cells occurred in greater proportions under cool conditions, but dead small larvae (second-third instars) seemed to occur in greater proportions under hot conditions. Pollen ball cells with unhatched eggs and first instars (in the chorion) occurred in lesser proportions under hot conditions.

Do artificial nests simulate nest success of greater sage-grouse?

OpenAIRE

Dinkins, Jonathan B.; Conover, Michael R.; Mabray, Scott T.

2013-01-01

Artificial nests have been used to study factors affecting nest success because researchers can manipulate them more than natural bird nests. Many researchers have questioned the validity of generalizing the results from artificial nests onto naturally occurring nests. Other studies have assessed the validity of artificial nest studies by simultaneously comparing overall depredation or daily survival rates, depredation timing, predator species, or habitat characteristics of artificial and nat...

Nest structure and notes on the social behavior of Augochlora amphitrite (Schrottky (Hymenoptera, Halictidae

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Milagros Dalmazzo

2012-05-01

Full Text Available The nesting biology of Augochlora (Augochlora amphitrite (Schrottky in a natural reserve in the Province of Buenos Aires, Argentina, is described. The species nests in decaying wood. Two types of nest architecture were found, which differed according to the substrate where they were built, either soft or hard wood. Nests in soft wood had the cells grouped in clusters surrounded by a cavity, and the clusters were supported by a varying number of pillars. Nests constructed in decomposing portions of cracks in otherwise hard wood had the cells constructed against the walls, without any pillars or surrounding cavity. Cells of both types of nests were oriented in all directions, without any detectable pattern. Measurements and characteristics of the nests are tabulated and compared to those known for other species of Augochlora s. str. Behavioral observations of active nests are indicative of a social division of tasks in A. amphitrite. Such observations include nests with several females, some of which were never observed outside the nests, females with different degrees of wear and of ovary development, and at least one female that actively collected pollen which had much worn mandibles and wings, and undeveloped ovaries, all characteristics of the worker caste in social halictids.

Durable and Robust Solid Oxide Fuel Cells

DEFF Research Database (Denmark)

Hjalmarsson, Per; Knibbe, Ruth; Hauch, Anne

project had as one of its’ overarching goals to improve durability and robustness of the Danish solid oxide fuel cells. The project focus was on cells and cell components suitable for SOFC operation in the temperature range 600 – 750 °C. The cells developed and/or studied in this project are intended......The solid oxide fuel cell (SOFC) is an attractive technology for the generation of electricity with high efficiency and low emissions. Risø DTU (now DTU Energy Conversion) works closely together with Topsoe Fuel Cell A/S in their effort to bring competitive SOFC systems to the market. This 2-year...... for use within the CHP (Combined Heat and Power) market segment with stationary power plants in the range 1 – 250 kWe in mind. Lowered operation temperature is considered a good way to improve the stack durability since corrosion of the interconnect plates in a stack is lifetime limiting at T > 750 °C...

PyNEST: a convenient interface to the NEST simulator

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Jochen M Eppler

2009-01-01

Full Text Available The neural simulation tool NEST (http://www.nest-initiative.org is a simulator for heterogeneous networks of point neurons or neurons with a small number of compartments. It aims at simulations of large neural systems with more than 10^4 neurons and 10^7 to 10^9 synapses. NEST is implemented in C++ and can be used on a large range of architectures from single-core laptops over multi-core desktop computers to super-computers with thousands of processor cores. Python (http://www.python.org is a modern programming language that has recently received considerable attention in Computational Neuroscience. Python is easy to learn and has many extension modules for scientific computing (e.g. http://www.scipy.org. In this contribution we describe PyNEST, the new user interface to NEST. PyNEST combines NEST’s efficient simulation kernel with the simplicity and flexibility of Python. Compared to NEST’s native simulation language SLI, PyNEST makes it easier to set up simulations, generate stimuli, and analyze simulation results. We describe how PyNEST connects NEST and Python and how it is implemented. With a number of examples, we illustrate how it is used.

The TMI regenerable solid oxide fuel cell

Science.gov (United States)

Cable, Thomas L.

1995-04-01

Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. These systems generally consist of photovoltaic solar arrays which operate during sunlight cycles to provide system power and regenerate fuel (hydrogen) via water electrolysis; during dark cycles, hydrogen is converted by the fuel cell into system. The currently preferred configuration uses two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Fuel cell/electrolyzer system simplicity, reliability, and power-to-weight and power-to-volume ratios could be greatly improved if both power production (fuel cell) and power storage (electrolysis) functions can be integrated into a single unit. The Technology Management, Inc. (TMI), solid oxide fuel cell-based system offers the opportunity to both integrate fuel cell and electrolyzer functions into one unit and potentially simplify system requirements. Based an the TMI solid oxide fuel cell (SOPC) technology, the TMI integrated fuel cell/electrolyzer utilizes innovative gas storage and operational concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H2O electrode (SOFC anode/electrolyzer cathode) materials for solid oxide, regenerative fuel cells. Improved H2/H2O electrode materials showed improved cell performance in both fuel cell and electrolysis modes in reversible cell tests. ln reversible fuel cell/electrolyzer mode, regenerative fuel cell efficiencies (ratio of power out (fuel cell mode) to power in (electrolyzer model)) improved from 50 percent (using conventional electrode materials) to over 80 percent. The new materials will allow the TMI SOFC system to operate as both the electrolyzer and fuel cell in a single unit. Preliminary system designs have also been developed which indicate the technical feasibility of using the TMI SOFC

Variability in nest survival rates and implications to nesting studies

Science.gov (United States)

Klett, A.T.; Johnson, D.H.

1982-01-01

We used four reasonably large samples (83-213) of Mallard (Anas platyrhynchos) and Blue-winged Teal (A. discors) nests on an interstate highway right-of-way in southcentral North Dakota to evaluate potential biases in hatch-rate estimates. Twelve consecutive, weekly searches for nests were conducted with a cable-chain drag in 1976 and 1977. Nests were revisited at weekly intervals. Four methods were used to estimate hatch rates for the four data sets: the Traditional Method, the Mayfield Method, and two modifications of the Mayfield Method that are sometimes appropriate when daily mortality rates of nests are not constant. Hatch rates and the average age of nests at discovery declined as the interval between searches decreased, suggesting that mortality rates were not constant in our samples. An analysis of variance indicated that daily mortality rates varied with the age of nests in all four samples. Mortality was generally highest during the early laying period, moderately high during the late laying period, and lowest during incubation. We speculate that this relationship of mortality to nest age might be due to the presence of hens at nests or to differences in the vulnerability of nest sites to predation. A modification of the Mayfield Method that accounts for age-related variation in nest mortality was most appropriate for our samples. We suggest methods for conducting nesting studies and estimating nest success for species possessing similar nesting habits.

Pseudomelanocytic nests mimicking atypical melanocytic proliferations: first reported cases in the oral cavity.

Science.gov (United States)

Boros, Audrey L; Handlers, Janice P; Melrose, Raymond J

2014-10-01

The concept of pseudomelanocytic nests has been recently described in the dermatology literature. To our knowledge, this entity has yet to be published in the oral pathology literature. We report 2 cases with features of pseudomelanocytic nests. In both instances, nests of cells suspicious for melanocytes were observed. Interpretation of melan-A was negative. Both cases showed strong and diffuse immunoreactivity of the nested cells to CD68. This immunohistochemical staining pattern is most consistent with a melanophage identity. Pseudomelanocytic nests are a recently described entity that represents a potential diagnostic pitfall. Distinguishing pseudomelanocytic nests from an authentic atypical melanocytic proliferation can be challenging and is important for appropriate patient management. Clinicopathologic correlation with cautious interpretation of immunohistochemistry may be necessary to arrive at the correct diagnosis. These cases represent the first reports of pseudomelanocytic nests in the oral pathology literature. Copyright © 2014 Elsevier Inc. All rights reserved.

Chimeric antigen receptor T-cell therapy for solid tumors

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Kheng Newick

2016-01-01

Full Text Available Chimeric antigen receptor (CAR T cells are engineered constructs composed of synthetic receptors that direct T cells to surface antigens for subsequent elimination. Many CAR constructs are also manufactured with elements that augment T-cell persistence and activity. To date, CAR T cells have demonstrated tremendous success in eradicating hematological malignancies (e.g., CD19 CARs in leukemias. This success is not yet extrapolated to solid tumors, and the reasons for this are being actively investigated. Here in this mini-review, we discuss some of the key hurdles encountered by CAR T cells in the solid tumor microenvironment.

Why wasp foundresses change nests: relatedness, dominance, and nest quality.

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Perttu Seppä

Full Text Available The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a combination of ecological and relatedness factors. Advantages through increased lifetime success of individuals and nests drives foundresses of the social wasp Polistes from solitary to social nest founding. We studied reproductive options of spring foundresses of P. carolina by monitoring individually-marked wasps and assessing reproductive success of each foundress by using DNA microsatellites. We examined what behavioral decisions foundresses make after relaxing a strong ecological constraint, shortage of nesting sites. We also look at the reproductive consequences of different behaviors. As in other Polistes, the most successful strategy for a foundress was to initiate a nest as early as possible and then accept others as subordinates. A common feature for many P. carolina foundresses was, however, that they reassessed their reproductive options by actively monitoring other nests at the field site and sometimes moving permanently to new nests should that offer better (inclusive fitness prospects compared to their original nests. A clear motivation for moving to new nests was high genetic relatedness; by the end of the foundress period all females were on nests with full sisters.

Why Wasp Foundresses Change Nests: Relatedness, Dominance, and Nest Quality

Science.gov (United States)

Seppä, Perttu; Queller, David C.; Strassmann, Joan E.

2012-01-01

The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a combination of ecological and relatedness factors. Advantages through increased lifetime success of individuals and nests drives foundresses of the social wasp Polistes from solitary to social nest founding. We studied reproductive options of spring foundresses of P. carolina by monitoring individually-marked wasps and assessing reproductive success of each foundress by using DNA microsatellites. We examined what behavioral decisions foundresses make after relaxing a strong ecological constraint, shortage of nesting sites. We also look at the reproductive consequences of different behaviors. As in other Polistes, the most successful strategy for a foundress was to initiate a nest as early as possible and then accept others as subordinates. A common feature for many P. carolina foundresses was, however, that they reassessed their reproductive options by actively monitoring other nests at the field site and sometimes moving permanently to new nests should that offer better (inclusive) fitness prospects compared to their original nests. A clear motivation for moving to new nests was high genetic relatedness; by the end of the foundress period all females were on nests with full sisters. PMID:23049791

Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird.

Science.gov (United States)

Hollander, Franck A; Van Dyck, Hans; San Martin, Gilles; Titeux, Nicolas

2015-01-01

In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius collurio) that recently expanded its breeding habitat into open areas in plantation forests. This passerine bird shows a strong preference for forest habitat, but it has a higher nest success in farmland. We tested whether higher abundance of nest predators in the preferred habitat or, alternatively, a decoupling of nest predator abundance and nest predation explained this observed pattern of maladaptive habitat selection. More than 90% of brood failures were attributed to nest predation. Nest predator abundance was more than 50% higher in farmland, but nest predation was 17% higher in forest. Differences between nest predation on actual shrike nests and on artificial nests suggested that parent shrikes may facilitate nest disclosure for predators in forest more than they do in farmland. The level of caution by parent shrikes when visiting their nest during a simulated nest predator intrusion was the same in the two habitats, but nest concealment was considerably lower in forest, which contributes to explaining the higher nest predation in this habitat. We conclude that a decoupling of nest predator abundance and nest predation may create ecological traps in human-modified environments.

Nest Site Characteristics of Cavity Nesting Birds in Central Missouri

Science.gov (United States)

Jeffery D. Brawn; Bernice Tannenbaum; Keith E. Evans

1984-01-01

Two study sites in central Missouri oak-hickory forests were searched for nest sites of cavity nesting birds. Researchers located and measured 133 nests of 11 species. Cavity nesting bird habitat selection is affected by both snag characteristics and vegetation structure.

Nesting biology of four Tetrapedia species in trap-nests (Hymenoptera:Apidae:Tetrapediini

Directory of Open Access Journals (Sweden)

Evandro Camillo

2005-06-01

Full Text Available The nests used in this study were obtained from trap-nests (tubes of cardboard and cut bamboo stems placed on Santa Carlota Farm (Itaoca Section-IS, Santana Section-SS and Cerrado-Ce, Cajuru, SP, Brazil. The number of nests and corresponding species obtained were as follows: 516 nests of T. curvitarsis, 104 of T. rugulosa, 399 of T. diversipes and 98 of T. garofaloi. The most abundant species from SS and Ce was T.curvitarsis, and from IS it was T. diversipes. In general, most nests were collected during the hot and wet season (September to April. The nests were constructed with sand and an oily substance, and a single female established them. The cells were constructed in a linear series, sometimes followed by a vestibular cell. The number of brood cells ranged from 1 to 10 in T. curvitarsis (n=200, and in T. garofaloi (n=51, from 1 to 8 (n=30 in T. rugulosa, and from 1 to 6 (n=37 in T. diversipes. The pollen mass (pollen + oily substance contained a hollow, sometimes divided by a transverse ridge, on the exposed face of the pollen mass. The egg was vertically positioned in the lower part of the hollow. At times, the closing of a cell was initiated before provisioning was completed, with a construction of a collar at the cell limit. In some nests the final cellular partition also acted as a closure plug. Females began activities at 6:18 a.m.and ended between 3:31 and 6:26 p.m. Some females (T. curvitarsis , T. rugulosa and T. garofaloi did not spend the nights at their nests, returning to them only the following morning with additional material. In general, the development period (for males and females was greater in nests collected near the end of the hot and wet season than it was for nests collected in other months. Sex ratios for each species were as follows: T. curvitarsis, 1:1; T. rugulosa , 1.6:1 female; T. diversipes, 1.9:1; T. garofaloi, 2.8:1. Males and females of T. diversipes exhibited statistically similar sizes and in the other

Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird.

Directory of Open Access Journals (Sweden)

Franck A Hollander

Full Text Available In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius collurio that recently expanded its breeding habitat into open areas in plantation forests. This passerine bird shows a strong preference for forest habitat, but it has a higher nest success in farmland. We tested whether higher abundance of nest predators in the preferred habitat or, alternatively, a decoupling of nest predator abundance and nest predation explained this observed pattern of maladaptive habitat selection. More than 90% of brood failures were attributed to nest predation. Nest predator abundance was more than 50% higher in farmland, but nest predation was 17% higher in forest. Differences between nest predation on actual shrike nests and on artificial nests suggested that parent shrikes may facilitate nest disclosure for predators in forest more than they do in farmland. The level of caution by parent shrikes when visiting their nest during a simulated nest predator intrusion was the same in the two habitats, but nest concealment was considerably lower in forest, which contributes to explaining the higher nest predation in this habitat. We conclude that a decoupling of nest predator abundance and nest predation may create ecological traps in human-modified environments.

Nesting biology of Centris (Hemisiella tarsata Smith (Hymenoptera, Apidae, Centridini

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Cândida M. L. Aguiar

2004-09-01

Full Text Available Nests of Centris tarsata Smith, 1874 were obtained from trap-nests in areas of dry semi-deciduous forest (Baixa Grande and caatinga (Ipirá, in the State of Bahia. Nesting occurred in bamboo canes and in tubes of black cardboard with 5.8 cm (= small tube and 10.5 cm (= large tube in length and 0.6 and 0.8 cm in diameter, respectively. In both areas C. tarsata nested during the wet season producing four generations in Baixa Grande and three generations in Ipirá. The immatures of one generation underwent diapause at both sites. The bees constructed their nests with a mixture of sand and oil. In general, the cells were elongated and arranged in linear series with its opening pointing towards the nest entrance. Completed nests had two to three cells in small tubes, one to seven cells in large tubes, and two to 13 cells in bamboo canes. The nest plug resembled an uncompleted cell and was externally covered with oil. The cells were provisioned with pollen, oil, and nectar. Nests were parasitized by Mesocheira bicolor (Fabricius, 1804 (Hymenoptera: Apidae and other not identify bee species.Ninhos de Centris tarsata Smith, 1874 foram obtidos através da utilização de ninhos-armadilha, em áreas de floresta estacional semi-decídua (Baixa Grande e de caatinga (Ipirá, no Estado da Bahia. A nidificação ocorreu em gomos de bambus e em tubos de cartolina preta, estes com comprimentos de 5,8 cm (= tubos pequenos e 10,5 cm (= tubos grandes, e diâmetro de 0,6 e 0,8 cm, respectivamente. Em ambas as áreas C. tarsata nidificou durante a estação úmida, produzindo quatro gerações anuais em Baixa Grande e três em Ipirá. Os imaturos de uma das gerações passaram por diapausa em ambos os locais. As abelhas construíram seus ninhos com uma mistura de areia e óleo. Em geral, as células foram alongadas e arranjadas em série linear, com sua abertura dirigida para a entrada do ninho. Os ninhos completados tinham de duas a três células nos tubos pequenos

Electrode Design for Low Temperature Direct-Hydrocarbon Solid Oxide Fuel Cells

Science.gov (United States)

Chen, Fanglin (Inventor); Zhao, Fei (Inventor); Liu, Qiang (Inventor)

2015-01-01

In certain embodiments of the present disclosure, a solid oxide fuel cell is described. The solid oxide fuel cell includes a hierarchically porous cathode support having an impregnated cobaltite cathode deposited thereon, an electrolyte, and an anode support. The anode support includes hydrocarbon oxidation catalyst deposited thereon, wherein the cathode support, electrolyte, and anode support are joined together and wherein the solid oxide fuel cell operates a temperature of 600.degree. C. or less.

Electrode design for low temperature direct-hydrocarbon solid oxide fuel cells

Science.gov (United States)

Chen, Fanglin; Zhao, Fei; Liu, Qiang

2015-10-06

In certain embodiments of the present disclosure, a solid oxide fuel cell is described. The solid oxide fuel cell includes a hierarchically porous cathode support having an impregnated cobaltite cathode deposited thereon, an electrolyte, and an anode support. The anode support includes hydrocarbon oxidation catalyst deposited thereon, wherein the cathode support, electrolyte, and anode support are joined together and wherein the solid oxide fuel cell operates a temperature of 600.degree. C. or less.

Cancer stem cells in solid tumors: elusive or illusive?

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Lehrach Hans R

2010-05-01

Full Text Available Abstract During the past years in vivo transplantation experiments and in vitro colony-forming assays indicated that tumors arise only from rare cells. These cells were shown to bear self-renewal capacities and the ability to recapitulate all cell types within an individual tumor. Due to their phenotypic resemblance to normal stem cells, the term "cancer stem cells" is used. However, some pieces of the puzzle are missing: (a a stringent definition of cancer stem cells in solid tumors (b specific markers that only target cells that meet the criteria for a cancer stem cell in a certain type of tumor. These missing parts started an ongoing debate about which is the best method to identify and characterize cancer stem cells, or even if their mere existence is just an artifact caused by the experimental procedures. Recent findings query the cancer stem cell hypothesis for solid tumors itself since it was shown in xenograft transplantation experiments that under appropriate conditions tumor-initiating cells are not rare. In this review we critically discuss the challenges and prospects of the currently used major methods to identify cancer stem cells. Further on, we reflect the present discussion about the existence of cancer stem cells in solid tumors as well as the amount and characteristics of tumor-initiating cells and finally provide new perspectives like the correlation of cancer stem cells and induced pluripotent cells.

Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program

Energy Technology Data Exchange (ETDEWEB)

Nguyen Minh

2006-07-31

This report summarizes the work performed for Phase I (October 2001 - August 2006) under Cooperative Agreement DE-FC26-01NT41245 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled 'Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program'. The program focuses on the development of a low-cost, high-performance 3-to-10-kW solid oxide fuel cell (SOFC) system suitable for a broad spectrum of power-generation applications. During Phase I of the program significant progress has been made in the area of SOFC technology. A high-efficiency low-cost system was designed and supporting technology developed such as fuel processing, controls, thermal management, and power electronics. Phase I culminated in the successful demonstration of a prototype system that achieved a peak efficiency of 41%, a high-volume cost of $724/kW, a peak power of 5.4 kW, and a degradation rate of 1.8% per 500 hours. . An improved prototype system was designed, assembled, and delivered to DOE/NETL at the end of the program. This prototype achieved an extraordinary peak efficiency of 49.6%.

Nest Architectural Patterns by Three Wasp Species ( and with Reference to Their Behavior

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Farzana Perveen

2013-01-01

Full Text Available In the present study, the nest architectural patterns, elemental analysis and their behavior were carried out in three wasp species: Vespa velutina (Lepeletier, Polistes flavus (Cresson and Sceliphron formosum (Smith from the different localities of the Mansehra, Pakistan. The V. velutina nest was completely closed except for one opening for entry or exit with 1–10 layers of hexagonal cells inside the nest. The nests of P. flavus were found among bunches of leaves of trees with 1–5 layers and hexagonal cells same as in V. velutina. Nests of the S. formosum were pitcher-shaped, found in muddy places, and consisted of 1–10 cells. Social behavior of wasps showed strong foraging, defensive behaviors, pseudo-attack, subsequent erratic flight, wing buzzing, mandibular pecking, abdominal pumping and abdominal twisting with highly developed parental care. It was concluded that the behaviors of these 3 wasp species was highly developed as compared with other insects.

Unique nest architecture in the North African osmiine bee Hoplitis (Hoplitis mucida (Hymenoptera, Megachilidae

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Andreas Müller

2017-10-01

Full Text Available The osmiine bee species Hoplitis mucida is considered to consist of two subspecies with H. mucida mucida (Dours, 1873 ranging from northwestern Africa to Israel and Jordan and H. mucida stecki (Frey-Gessner, 1908 occurring in southwestern Europe and Sicily. The discovery of nests of H. mucida in Morocco and Tunisia revealed striking differences in the nesting biology of the two subspecies. In North Africa, females construct fully exposed, cake-like nests of mud on the flat surface of rocks and stones containing 8–12 vertically oriented brood cells, rendering these nests unique among osmiine bees regarding both nesting site and nest architecture. In contrast, in Europe females build their few-celled mud nests inside small rock cavities. This discrepancy in the nesting biology is paralleled by considerable morphological differences between the two subspecies suggestive of a long geographical isolation. Due to these biological and morphological differences, we propose to elevate the European subspecies H. mucida stecki to species rank.

Solid Oxide Electrolyser Cell

DEFF Research Database (Denmark)

Jensen, Søren Højgaard

Solid oxide fuel cells (SOFCs) produced at Risø National Laboratory was tested as steam electrolysers under various current densities, operating temperatures and steam partial pressures. At 950 °C and a cell voltage of 1.48V the current density was -3.6A/cm2 with app. 30% H2 + 70% H2O in the inlet...... it is possible to achieve a production price of 0.7 US$/kg H2 with an electricity price of 1.3 US¢/kWh. The cell voltage was measured as function of time. In test ofabout two month of duration a long-term degradation was observed. At 850 °C, -0.5 A/cm2 with 50 vol% H2 the degradation rate was app. 20 mV/1000h...

Effect of solid distribution on elastic properties of open-cell cellular solids using numerical and experimental methods.

Science.gov (United States)

Zargarian, A; Esfahanian, M; Kadkhodapour, J; Ziaei-Rad, S

2014-09-01

Effect of solid distribution between edges and vertices of three-dimensional cellular solid with an open-cell structure was investigated both numerically and experimentally. Finite element analysis (FEA) with continuum elements and appropriate periodic boundary condition was employed to calculate the elastic properties of cellular solids using tetrakaidecahedral (Kelvin) unit cell. Relative densities between 0.01 and 0.1 and various values of solid fractions were considered. In order to validate the numerical model, three scaffolds with the relative density of 0.08, but different amounts of solid in vertices, were fabricated via 3-D printing technique. Good agreement was observed between numerical simulation and experimental results. Results of numerical simulation showed that, at low relative densities (solid fraction in vertices. By fitting a curve to the data obtained from the numerical simulation and considering the relative density and solid fraction in vertices, empirical relations were derived for Young׳s modulus and Poisson׳s ratio. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nest use is influenced by the positions of nests and drinkers in aviaries.

Science.gov (United States)

Lentfer, T L; Gebhardt-Henrich, S G; Fröhlich, E K F; von Borell, E

2013-06-01

The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nests.

Nesting biology of four species of Trypoxylon (Trypargilum (Hymenoptera: Crabronidae in Chaco Serrano woodland, Central Argentina

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Mariana L Musicante

2010-12-01

Full Text Available Trypoxylon (Trypargilum (Crabronidae wasps are solitary spider predators that can build their nests in artificial trap-nests, which enables study of their nesting architecture and biology. Twenty traps (each containing 15-30 internodes of cane were placed in each of nine sites of Chaco Serrano Woodland in Central Argentina (Córdoba in October 2005, and were recovered in June 2006. We obtained 91 nests of four species of Trypoxylon (Trypargilum. In the laboratory, each Trypoxylon nest was sectioned longitudinally to study its architecture. The number of brood cells was counted, and the occurrence and length of vestibular and intercalary cells and the pre-closing plug space were recorded. We measured the diameter of the cane entrance, total length of the nest, length of each brood cell, maximum thickness of mud partitions and closing plug thickness. We also recorded the cell contents: the wasps, their natural enemies and the prey spiders. Mortality was assessed and the sex ratio calculated for each species. Finally, the nests were examined to help clarify the function of the vestibular cell. The nest architecture was similar in the four species, with linear brood cells located one after the other separated by mud partitions, as in other species of the subgenus Trypargilum. Forty-eight percent of the nests had vestibular cells, but only two had intercalary cells. The thickness of the mud partitions and the length of the brood cells differed among species and were related to the size of the emerged wasp. The diameter of the nest entrance was directly related to the average length of the fore-tibia. Sex ratios of all species did not deviate from 0.5. Mortality due to parasitoids (Eulophidae; Melittobia sp. was similar among species, while the mortality due to cuckoo wasps (Chrysididae in T. lactitarse was higher than in the other species. The presence of vestibular cells was not related either to the mortality due to natural enemies or to the

Development of the plastic solid-dye cell for tunable solid-state dye lasers and study on its optical properties

Energy Technology Data Exchange (ETDEWEB)

Ko, Do Kyeong; Lee, Jong Min; Cha, Byung Heon; Jung, E. C.; Kim, Hyun Su; Lim, Gwon

2001-01-01

we have fabricated solid-state dyes with PMMA and sol-gel materials. We developed single longitudianl mode solid-state dye laser with the linewidth of less than 500MHz. We have constructed a self-seeded laser and observed the increase of the output power because of self-seeding effect. We investigated the operating characteristics of the dualwave laser oscillator and DFDL with solid-state dyes. And we have constructed the 3-color solid-state dye laser oscillator and amplifier system and observed 3-color operation. We also improved the laser oscliiator with disk-type solid-state dye cell which can be translated and rotated with the help of the two stepping motors. With the help of computer control, we could constantly changed the illuminated area of the dye cell and, therefore, were able to achieve long time operation and to use almost the entire region of the solid-state dye cell.

Interactive effects between nest microclimate and nest vegetation structure confirm microclimate thresholds for Lesser Prairie-Chicken nest survival

Science.gov (United States)

Grisham, Blake A.; Godar, Alixandra J.; Boal, Clint W.; Haukos, David A.

2016-01-01

The range of Lesser Prairie-Chickens (Tympanuchus pallidicinctus) spans 4 unique ecoregions along 2 distinct environmental gradients. The Sand Shinnery Oak Prairie ecoregion of the Southern High Plains of New Mexico and Texas is environmentally isolated, warmer, and more arid than the Short-Grass, Sand Sagebrush, and Mixed-Grass Prairie ecoregions in Colorado, Kansas, Oklahoma, and the northeast panhandle of Texas. Weather is known to influence Lesser Prairie-Chicken nest survival in the Sand Shinnery Oak Prairie ecoregion; regional variation may also influence nest microclimate and, ultimately, survival during incubation. To address this question, we placed data loggers adjacent to nests during incubation to quantify temperature and humidity distribution functions in 3 ecoregions. We developed a suite of a priori nest survival models that incorporated derived microclimate parameters and visual obstruction as covariates in Program MARK. We monitored 49 nests in Mixed-Grass, 22 nests in Sand Shinnery Oak, and 30 nests in Short-Grass ecoregions from 2010 to 2014. Our findings indicated that (1) the Sand Shinnery Oak Prairie ecoregion was hotter and drier during incubation than the Mixed- and Short-Grass ecoregions; (2) nest microclimate varied among years within ecoregions; (3) visual obstruction was positively associated with nest survival; but (4) daily nest survival probability decreased by 10% every half-hour when temperature was greater than 34°C and vapor pressure deficit was less than −23 mmHg during the day (about 0600–2100 hours). Our major finding confirmed microclimate thresholds for nest survival under natural conditions across the species' distribution, although Lesser Prairie-Chickens are more likely to experience microclimate conditions that result in nest failures in the Sand Shinnery Oak Prairie ecoregion. The species would benefit from identification of thermal landscapes and management actions that promote cooler, more humid nest microclimates.

Nesting biology of Paravespa rex (von Schulthess 1924) (Hymenoptera: Vespidae: Eumeninae) in the Crimea, Ukraine.

Science.gov (United States)

Fateryga, Alexander V; Ivanov, Sergey P

2013-01-01

Paravespa rex is the only species of the wasp genus Paravespa that occurs in Europe. Females of this species nest in clay loam soil of proluvial terraces and deluvial aprons of badlands. The nests are vertical burrows 10-12 cm deep, surmounted by turrets of two distinct architectural forms: funnel-shaped and curved. The nests contain 1-3 vertical cells (mean-1.9) not different from the other parts of nest burrow. An egg is laid onto the bottom of the cell without attaching; it stands vertically via the moist adhesive surface of the bottom and then with the help of the position of the first prey, which is laid around the egg. The species is univoltine; prepupae hibernate in the cocoon for one or several years. Females hunt for caterpillars of two species of the noctuid genus Heliotis; 3-7 caterpillars (mean-3.7) are stored per cell. Adult feeding is recorded on flowers of Thymus tauricus. Males look for females at their water-collecting sites. Only a third of the cells are successful; the other ones are damaged by rain and the gold wasp, Chrysis valesiana, parasitizing in the nests. Nest-building and hunting activity of the species is described with the duration of certain nesting acts. Nesting biology of Paravespa species, rarity of P. rex, turret function, egg position, and measures for species conservation are discussed.

Nest Mosquito Trap quantifies contact rates between nesting birds and mosquitoes.

Science.gov (United States)

Caillouët, Kevin A; Riggan, Anna E; Rider, Mark; Bulluck, Lesley P

2012-06-01

Accurate estimates of host-vector contact rates are required for precise determination of arbovirus transmission intensity. We designed and tested a novel mosquito collection device, the Nest Mosquito Trap (NMT), to collect mosquitoes as they attempt to feed on unrestrained nesting birds in artificial nest boxes. In the laboratory, the NMT collected nearly one-third of the mosquitoes introduced to the nest boxes. We then used these laboratory data to estimate our capture efficiency of field-collected bird-seeking mosquitoes collected over 66 trap nights. We estimated that 7.5 mosquitoes per trap night attempted to feed on nesting birds in artificial nest boxes. Presence of the NMT did not have a negative effect on avian nest success when compared to occupied nest boxes that were not sampled with the trap. Future studies using the NMT may elucidate the role of nestlings in arbovirus transmission and further refine estimates of nesting bird and vector contact rates. © 2012 The Society for Vector Ecology.

Mourning Dove nesting habitat and nest success in Central Missouri

Science.gov (United States)

Drobney, R.D.; Schulz, J.H.; Sheriff, S.L.; Fuemmeler, W.J.

1998-01-01

Previous Mourning Dove (Zenaida macroura) nesting studies conducted in areas containing a mixture of edge and continuous habitats have focused on edge habitats. Consequently, little is known about the potential contribution of continuous habitats to dove production. In this study we evaluated the relative importance of these two extensive habitat types by monitoring the habitat use and nest success of 59 radio-marked doves during 1990-1991 in central Missouri. Of 83 nests initiated by our marked sample, most (81.9%) were located in edge habitats. Although continuous habitats were selected less as nest sites, the proportion of successful nests did not differ significantly from that in edge habitats. Our data indicate that continuous habitats should not be considered marginal nesting habitat. If the intensity of use and nest success that we observed are representative regionally or nationally, continuous habitats could contribute substantially to annual Mourning Dove production because of the high availability of these habitats throughout much of the Mourning Dove breeding range.

Ovarian Brenner tumors and Walthard nests: a histologic and immunohistochemical study.

Science.gov (United States)

Roma, Andres A; Masand, Ramya P

2014-12-01

Brenner tumors are composed of urothelial/transitional-type epithelium and, hence, are morphologically similar to Walthard nests and tubal/mesothelial transitional metaplasia. In this study, we analyzed immunohistochemical markers on Brenner tumors to explore Müllerian as well as Wolffian and germ cell derivation. We also attempted to explore their possible association with tubal/paratubal Walthard nests/transitional metaplasia, using the same immunostains. Thirty-two consecutive cases of Brenner tumors were identified. Thirteen (43%) of the patients had Walthard nests in the tubal/periovarian soft tissue. All Brenner tumors were diffusely positive for GATA3 (strongly positive in 30/32 and weakly positive in the remaining 2) and negative for PAX8, PAX2, and SALL4. Similarly, all Walthard nests were positive for GATA3, whereas only 3 (23%) of 13 showed occasional PAX8 expression; all were negative for PAX2 and SALL4. In our study, more than 40% of Brenner tumors had associated Walthard nests. The similar morphology and immunoprofile of Brenner tumors and Walthard nests suggest a probable link between Brenner tumors and Walthard nests. Two additional cases presented highlight small transitional lesions involving the ovary: a possible precursor lesion or the initial steps of Brenner tumor formation. Brenner tumors and most Walthard nests lacked staining for Müllerian (PAX8 and PAX2) and germ cell tumor markers (SALL4). Copyright © 2014 Elsevier Inc. All rights reserved.

Construction patterns of birds’ nests provide insight into nest-building behaviours

Directory of Open Access Journals (Sweden)

Lucia Biddle

2017-02-01

Full Text Available Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process.

Construction patterns of birds’ nests provide insight into nest-building behaviours

Science.gov (United States)

Goodman, Adrian M.

2017-01-01

Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula) nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process. PMID:28265501

Construction patterns of birds' nests provide insight into nest-building behaviours.

Science.gov (United States)

Biddle, Lucia; Goodman, Adrian M; Deeming, D Charles

2017-01-01

Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch ( Pyrrhula pyrrhula ) nests as a model for open-nesting songbird species that construct a "twig" nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process.

Detection of adenoviruses in shellfish by means of conventional-PCR, nested-PCR, and integrated cell culture PCR (ICC/PCR).

Science.gov (United States)

Rigotto, C; Sincero, T C M; Simões, C M O; Barardi, C R M

2005-01-01

We tested three PCR based methodologies to detect adenoviruses associated with cultivated oysters. Conventional-PCR, nested-PCR, and integrated cell culture-PCR (ICC/PCR) were first optimized using oysters seeded with know amounts of Adenovirus serotype 5 (Ad5). The maximum sensitivity for Ad5 detection was determined for each method, and then used to detect natural adenovirus contamination in oysters from three aquiculture farms in Florianopolis, Santa Catarina State, Brazil, over a period of 6 months. The results showed that the nested-PCR was more sensitive (limit of detection: 1.2 PFU/g of tissue) than conventional-PCR and ICC-PCR (limit of detection for both: 1.2 x 10(2)PFU/g of tissue) for detection of Ad5 in oyster extracts. Nested-PCR was able to detect 90% of Ad5 contamination in harvested oyster samples, while conventional-PCR was unable to detect Ad5 in any of the samples. The present work suggests that detection of human adenoviruses can be used as a tool to monitor the presence of human viruses in marine environments where shellfish grow, and that nested-PCR is the method of choice.

A unique nest-protection strategy in a new species of spider wasp.

Directory of Open Access Journals (Sweden)

Michael Staab

Full Text Available Hymenoptera show a great variation in reproductive potential and nesting behavior, from thousands of eggs in sawflies to just a dozen in nest-provisioning wasps. Reduction in reproductive potential in evolutionary derived Hymenoptera is often facilitated by advanced behavioral mechanisms and nesting strategies. Here we describe a surprising nesting behavior that was previously unknown in the entire animal kingdom: the use of a vestibular cell filled with dead ants in a new spider wasp (Hymenoptera: Pompilidae species collected with trap nests in South-East China. We scientifically describe the 'Bone-house Wasp' as Deuteragenia ossarium sp. nov., named after graveyard bone-houses or ossuaries. We show that D. ossarium nests are less vulnerable to natural enemies than nests of other sympatric trap-nesting wasps, suggesting an effective nest protection strategy, most likely by utilizing chemical cues emanating from the dead ants.

Notes on the Nest Architecture of Halictus senilis　(Eversmann) in Southeast Kazakhstan　(Hymenoptera, Halictidae)

OpenAIRE

Miyanaga, Ryoichi; Tadauchi, Osamu; Murao, Ryuki

2006-01-01

Four nests of Halictus senilis (Eversmann) were excavated near Chimkent, southeast Kazakhstan. The nest of H. senilis was similar in structure to nests of the other species of Halictus s. s., i.e., each cell directly, not by means of lateral, connected to the main burrow. On the other hand, the deviation from the typical nest structure of Halictus was found. The coexistence of delayed eusocial and solitary nests was suggested in this species.

Detection of tumor markers in prostate cancer and comparison of sensitivity between real time and nested PCR.

Science.gov (United States)

Matsuoka, Takayuki; Shigemura, Katsumi; Yamamichi, Fukashi; Fujisawa, Masato; Kawabata, Masato; Shirakawa, Toshiro

2012-06-27

The objective of this study is to investigate and compare the sensitivity in conventional PCR, quantitative real time PCR, nested PCR and western blots for detection of prostate cancer tumor markers using prostate cancer (PCa) cells. We performed conventional PCR, quantitative real time PCR, nested PCR, and western blots using 5 kinds of PCa cells. Prostate specific antigen (PSA), prostate specific membrane antigen (PSMA), and androgen receptor (AR) were compared for their detection sensitivity by real time PCR and nested PCR. In real time PCR, there was a significant correlation between cell number and the RNA concentration obtained (R(2)=0.9944) for PSA, PSMA, and AR. We found it possible to detect these markers from a single LNCaP cell in both real time and nested PCR. By comparison, nested PCR reached a linear curve in fewer PCR cycles than real time PCR, suggesting that nested PCR may offer PCR results more quickly than real time PCR. In conclusion, nested PCR may offer tumor maker detection in PCa cells more quickly (with fewer PCR cycles) with the same high sensitivity as real time PCR. Further study is necessary to establish and evaluate the best tool for PCa tumor marker detection.

Hurdles of CAR-T cell-based cancer immunotherapy directed against solid tumors.

Science.gov (United States)

Zhang, Bing-Lan; Qin, Di-Yuan; Mo, Ze-Ming; Li, Yi; Wei, Wei; Wang, Yong-Sheng; Wang, Wei; Wei, Yu-Quan

2016-04-01

Recent reports on the impressive efficacy of chimeric antigen receptor (CAR)-modified T cells against hematologic malignancies have inspired oncologists to extend these efforts for the treatment of solid tumors. Clinical trials of CAR-T-based cancer immunotherapy for solid tumors showed that the efficacies are not as remarkable as in the case of hematologic malignancies. There are several challenges that researchers must face when treating solid cancers with CAR-T cells, these include choosing an ideal target, promoting efficient trafficking and infiltration, overcoming the immunosuppressive microenvironment, and avoiding associated toxicity. In this review, we discuss the obstacles imposed by solid tumors on CAR-T cell-based immunotherapy and strategies adopted to improve the therapeutic potential of this approach. Continued investigations are necessary to improve therapeutic outcomes and decrease the adverse effects of CAR-T cell therapy in patients with solid malignancies in the future.

Exceptional Durability of Solid Oxide Cells

DEFF Research Database (Denmark)

Ebbesen, Sune; Mogensen, Mogens Bjerg

2010-01-01

Extensive efforts to resolve the degradation normally associated with solid oxide electrolysis cells (SOECs) have been conducted during the past decade. To date, the degradation is assumed to be caused by adsorption of impurities in the cathode, although no firm evidence for this degradation...

New Strategies for the Treatment of Solid Tumors with CAR-T Cells.

Science.gov (United States)

Zhang, Hao; Ye, Zhen-Long; Yuan, Zhen-Gang; Luo, Zheng-Qiang; Jin, Hua-Jun; Qian, Qi-Jun

2016-01-01

Recent years, we have witnessed significant progresses in both basic and clinical studies regarding novel therapeutic strategies with genetically engineered T cells. Modification with chimeric antigen receptors (CARs) endows T cells with tumor specific cytotoxicity and thus induce anti-tumor immunity against malignancies. However, targeting solid tumors is more challenging than targeting B-cell malignancies with CAR-T cells because of the histopathological structure features, specific antigens shortage and strong immunosuppressive environment of solid tumors. Meanwhile, the on-target/off-tumor toxicity caused by relative expression of target on normal tissues is another issue that should be reckoned. Optimization of the design of CAR vectors, exploration of new targets, addition of safe switches and combination with other treatments bring new vitality to the CAR-T cell based immunotherapy against solid tumors. In this review, we focus on the major obstacles limiting the application of CAR-T cell therapy toward solid tumors and summarize the measures to refine this new cancer therapeutic modality.

Improved clonality detection in B-cell lymphoma using a semi-nested modification of the BIOMED-2 PCR assay for IGH rearrangement: A paraffin-embedded tissue study.

Science.gov (United States)

Sakamoto, Yuma; Masaki, Ayako; Aoyama, Satsuki; Han, Shusen; Saida, Kosuke; Fujii, Kana; Takino, Hisashi; Murase, Takayuki; Iida, Shinsuke; Inagaki, Hiroshi

2017-09-01

The BIOMED-2 PCR protocol for targeting the IGH gene is widely employed for detecting clonality in B-cell malignancies. Unfortunately, the detection of clonality with this method is not very sensitive when paraffin sections are used as a DNA source. To increase the sensitivity, we devised a semi-nested modification of a JH consensus primer. The clonality detection rates of three assays were compared: the standard BIOMED-2, BIOMED-2 assay followed by BIOMED-2 re-amplification, and BIOMED-2 assay followed by semi-nested BIOMED-2. We tested more than 100 cases using paraffin-embedded tissues of various B-cell lymphomas, and found that the clonality detection rates with the above three assays were 63.9%, 79.6%, and 88.0%, respectively. While BIOMED-2 re-amplification was significantly more sensitive than the standard BIOMED-2, the semi-nested BIOMED-2 was significantly more sensitive than both the standard BIOMED-2 and BIOMED-2 re-amplification. An increase in sensitivity was observed in all lymphoma subtypes examined. In conclusion, tumor clonality may be detected in nearly 90% of B-cell lymphoma cases with semi-nested BIOMED-2. This ancillary assay may be useful when the standard BIOMED-2 fails to detect clonality in histopathologically suspected B-cell lymphomas. © 2017 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

Development of the plastic solid-dye cell for tunable solid-state dye lasers and study on its optical properties

Energy Technology Data Exchange (ETDEWEB)

Ko, Do Kyeong; Lee, Jong Min; Cha, Byung Heon; Yi, Jong Hoon; Lee, Kang Soo; Kim, Sung Ho; Lim, Gwon

2000-01-01

We have fabricated solid-state dyes with Copolex NK-55, which is the base element of plastic lens, and PMMA. We have measured the longevity of solid-state dyes doped in both polymers and found that PMMA has better properties than Coploex NK-55. We have realized the tuning range of 560-620 nm by doping rhodamine 6Gand rhodamin B in the manufactured solid-state dye laser oscillators. In the standing-wave cavity we achieved the slop efficiency of 10.8 percent and in the grazing incidence cavity, 1.2 percent. We have constructed a very compact grazing- incidence cavity which is only 6 cm long and the linewidth of the laser was less than 1.5 GHz with 3-ns pulse duration. And we have fabricated disk-type solid-state dye cell and installed it in the cavity in which the dye cell can be translated and rotated with the help of the two steeping motors. By this we could constantly changed the illuminated area of the dye cell and , therefore, were able to achieve long time operation and to use almost the entire region of the solid-state dye cell. (author)

Development of the plastic solid-dye cell for tunable solid-state dye lasers and study on its optical properties

International Nuclear Information System (INIS)

Ko, Do Kyeong; Lee, Jong Min; Cha, Byung Heon; Yi, Jong Hoon; Lee, Kang Soo; Kim, Sung Ho; Lim, Gwon

2000-01-01

We have fabricated solid-state dyes with Copolex NK-55, which is the base element of plastic lens, and PMMA. We have measured the longevity of solid-state dyes doped in both polymers and found that PMMA has better properties than Coploex NK-55. We have realized the tuning range of 560-620 nm by doping rhodamine 6G and rhodamin B in the manufactured solid-state dye laser oscillators. In the standing-wave cavity we achieved the slop efficiency of 10.8 percent and in the grazing incidence cavity, 1.2 percent. We have constructed a very compact grazing- incidence cavity which is only 6 cm long and the linewidth of the laser was less than 1.5 GHz with 3-ns pulse duration. And we have fabricated disk-type solid-state dye cell and installed it in the cavity in which the dye cell can be translated and rotated with the help of the two steeping motors. By this we could constantly changed the illuminated area of the dye cell and , therefore, were able to achieve long time operation and to use almost the entire region of the solid-state dye cell. (author)

The effects of cavity length on nest size, sex ratio and mortality of Centris (Heterocentris) analis (Hymenoptera, Apidae, Centridini)

OpenAIRE

Alonso , Juliana; Silva , Janaina; Garófalo , Carlos

2012-01-01

International audience; This study investigated the effects of different cavity lengths in trap-nests on the number of cells constructed per nest, sex ratio and mortality of offspring of Centris analis at three sites in Ribeirão Preto, São Paulo, Brazil. Cavity length did not affect the occupation rates of the trap-nests, with the exception of a preference for the shortest trap-nests found at one site. The number of cells per nest increased with trap-nest length. Cavity length affected neithe...

Phenotypic integration in an extended phenotype: among-individual variation in nest-building traits of the alfalfa leafcutting bee (Megachile rotundata).

Science.gov (United States)

Royauté, Raphaël; Wilson, Elisabeth S; Helm, Bryan R; Mallinger, Rachel E; Prasifka, Jarrad; Greenlee, Kendra J; Bowsher, Julia H

2018-03-02

Structures such as nests and burrows are an essential component of many organisms' life-cycle and require a complex sequence of behaviours. Because behaviours can vary consistently among individuals and be correlated with one another, we hypothesized that these structures would (1) show evidence of among-individual variation, (2) be organized into distinct functional modules and (3) show evidence of trade-offs among functional modules due to limits on energy budgets. We tested these hypotheses using the alfalfa leafcutting bee, Megachile rotundata, a solitary bee and important crop pollinator. Megachile rotundata constructs complex nests by gathering leaf materials to form a linear series of cells in pre-existing cavities. In this study, we examined variation in the following nest construction traits: reproduction (number of cells per nest and nest length), nest protection (cap length and number of leaves per cap), cell construction (cell size and number of leaves per cell) and cell provisioning (cell mass) from 60 nests. We found a general decline in investment in cell construction and provisioning with each new cell built. In addition, we found evidence for both repeatability and plasticity in cell provisioning with little evidence for trade-offs among traits. Instead, most traits were positively, albeit weakly, correlated (r ~ 0.15), and traits were loosely organized into covarying modules. Our results show that individual differences in nest construction are detectable at a level similar to that of other behavioural traits and that these traits are only weakly integrated. This suggests that nest components are capable of independent evolutionary trajectories. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

Sorting it out: bedding particle size and nesting material processing method affect nest complexity.

Science.gov (United States)

Robinson-Junker, Amy; Morin, Amelia; Pritchett-Corning, Kathleen; Gaskill, Brianna N

2017-04-01

As part of routine husbandry, an increasing number of laboratory mice receive nesting material in addition to standard bedding material in their cages. Nesting material improves health outcomes and physiological performance in mice that receive it. Providing usable nesting material uniformly and efficiently to various strains of mice remains a challenge. The aim of this study was to determine how bedding particle size, method of nesting material delivery, and processing of the nesting material before delivery affected nest building in mice of strong (BALB/cAnNCrl) and weak (C3H/HeNCrl) gathering abilities. Our data suggest that processing nesting material through a grinder in conjunction with bedding material, although convenient for provision of bedding with nesting material 'built-in', negatively affects the integrity of the nesting material and subsequent nest-building outcomes. We also found that C3H mice, previously thought to be poor nest builders, built similarly scored nests to those of BALB/c mice when provided with unprocessed nesting material. This was true even when nesting material was mixed into the bedding substrate. We also observed that when nesting material was mixed into the bedding substrate, mice of both strains would sort their bedding by particle size more often than if it were not mixed in. Our findings support the utility of the practice of distributing nesting material mixed in with bedding substrate, but not that of processing the nesting material with the bedding in order to mix them.

Near-ambient solid polymer fuel cell

Science.gov (United States)

Holleck, G. L.

1993-01-01

Fuel cells are extremely attractive for extraterrestrial and terrestrial applications because of their high energy conversion efficiency without noise or environmental pollution. Among the various fuel cell systems the advanced polymer electrolyte membrane fuel cells based on sulfonated fluoropolymers (e.g., Nafion) are particularly attractive because they are fairly rugged, solid state, quite conductive, of good chemical and thermal stability and show good oxygen reduction kinetics due to the low specific adsorption of the electrolyte on the platinum catalyst. The objective of this program is to develop a solid polymer fuel cell which can efficiently operate at near ambient temperatures without ancillary components for humidification and/or pressurization of the fuel or oxidant gases. During the Phase 1 effort we fabricated novel integral electrode-membrane structures where the dispersed platinum catalyst is precipitated within the Nafion ionomer. This resulted in electrode-membrane units without interfacial barriers permitting unhindered water diffusion from cathode to anode. The integral electrode-membrane structures were tested as fuel cells operating on H2 and O2 or air at 1 to 2 atm and 10 to 50 C without gas humidification. We demonstrated that cells with completely dry membranes could be self started at room temperature and subsequently operated on dry gas for extended time. Typical room temperature low pressure operation with unoptimized electrodes yielded 100 mA/cm(exp 2) at 0.5V and maximum currents over 300 mA/cm(exp 2) with low platinum loadings. Our results clearly demonstrate that operation of proton exchange membrane fuel cells at ambient conditions is feasible. Optimization of the electrode-membrane structure is necessary to assess the full performance potential but we expect significant gains in weight and volume power density for the system. The reduced complexity will make fuel cells also attractive for smaller and portable power supplies and as

Cavities in bromeliad stolons used as nest sites by Euglossa cordata (Hymenoptera, Euglossini

Directory of Open Access Journals (Sweden)

Samuel Boff

2018-02-01

Full Text Available Herein, we describe nests of the orchid bee Euglossa cordata that were constructed in cavities of Aechmea distichantha (Bromeliaceae stolons. We present data about nest and cell size, number of adults and brood, and analyses of larval provisions. The presence of E. cordata carcasses embedded in the resin of nest partitions indicates that these nests were used by multiple generations. Based on larval provisioning, E. cordata is polylectic and relies heavily on a few plant species.

Solid Oxide Cell and Stack Testing, Safety and Quality Assurance (SOCTESQA)

DEFF Research Database (Denmark)

Auer, C.; Lang, M.; Couturier, K.

2015-01-01

In the EU-funded project “SOCTESQA” partners from Europe and Singapore are working together to develop uniform and industry wide test procedures and protocols for solid oxide cells and stacks SOC cell/stack assembly. New application fields which are based on the operation of the SOC cell/stack as......In the EU-funded project “SOCTESQA” partners from Europe and Singapore are working together to develop uniform and industry wide test procedures and protocols for solid oxide cells and stacks SOC cell/stack assembly. New application fields which are based on the operation of the SOC cell...

A novel direct carbon fuel cell by approach of tubular solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Liu, Renzhu; Zhao, Chunhua; Li, Junliang; Zeng, Fanrong; Wang, Shaorong; Wen, Tinglian; Wen, Zhaoyin [CAS Key Laboratory of Materials for Energy Conversion, Shanghai Inorganic Energy Materials and Power Source Engineering Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS), 1295 Dingxi Road, Shanghai 200050 (China)

2010-01-15

A direct carbon fuel cell based on a conventional anode-supported tubular solid oxide fuel cell, which consisted of a NiO-YSZ anode support tube, a NiO-ScSZ anode functional layer, a ScSZ electrolyte film, and a LSM-ScSZ cathode, has been successfully achieved. It used the carbon black as fuel and oxygen as the oxidant, and a preliminary examination of the DCFC has been carried out. The cell generated an acceptable performance with the maximum power densities of 104, 75, and 47 mW cm{sup -2} at 850, 800, and 750 C, respectively. These results demonstrate the feasibility for carbon directly converting to electricity in tubular solid oxide fuel cells. (author)

Cell-model prediction of the melting of a Lennard-Jones solid

International Nuclear Information System (INIS)

Holian, B.L.

1980-01-01

The classical free energy of the Lennard-Jones 6-12 solid is computed from a single-particle anharmonic cell model with a correction to the entropy given by the classical correlational entropy of quasiharmonic lattice dynamics. The free energy of the fluid is obtained from the Hansen-Ree analytic fit to Monte Carlo equation-of-state calculations. The resulting predictions of the solid-fluid coexistence curves by this corrected cell model of the solid are in excellent agreement with the computer experiments

Pre-nesting and nesting behavior of the Swainson's warbler

Science.gov (United States)

Meanley, B.

1969-01-01

The Swainson?s Warbler is one of the least known of southern birds. Although fairly common in some parts of its summer range, observations of its breeding biology have been made by very few persons. The present study was conducted mostly at Macon, Georgia; Pendleton Ferry, Arkansas; and Dismal Swamp, Virginia....In central Georgia and east-central Arkansas, Swainson?s Warblers usually arrive on their territories during the first two weeks in April. Territories in several localities ranged in size from 0.3 to 4.8 acres. A color-marked Arkansas male occupied the same territory for at least four months. Hostile encounters between territorial male Swainson?s Warblers usually take place along the boundary of adjacent territories. Paired males were more aggressive than unpaired males. Toward the end of an encounter one of the two males would usually perform a display in which the wing and tail feathers were spread and the tail vibrated. Following boundary encounters males drifted back onto their territories and usually sang unbroken courses of songs for several minutes.....During pre-nesting at Macon, a mated pair spent the day mostly on the ground within 20 feet of each other, often foragin g 3 to 4 feet apart. What may have been a form of courtship display, in which the male flew from a perch down to the female and either pecked her rump or pounced on her, occurred about three times each hour throughout the day. During this period the male sang less than at other times during the breeding season.....First nests are usually built by the first week in May. Although other investigators reported finding nests of this species outside of the defended territory, all nests that I have found were within the territory. The large, bulky nest of this species usually is placed 2-6 feet above the ground. It is built by the female from materials gathered close to the nest site; and takes two or three days to complete.....Three and occasionally four white eggs are laid. The female

Open cup nests evolved from roofed nests in the early passerines.

Science.gov (United States)

Price, J Jordan; Griffith, Simon C

2017-02-08

The architectural diversity of nests in the passerine birds (order Passeriformes) is thought to have played an important role in the adaptive radiation of this group, which now comprises more than half of avian species and occupies nearly all terrestrial ecosystems. Here, we present an extensive survey and ancestral state reconstruction of nest design across the passerines, focusing on early Australian lineages and including members of nearly all passerine families worldwide. Most passerines build open cup-shaped nests, whereas a minority build more elaborate domed structures with roofs. We provide strong evidence that, despite their relative rarity today, domed nests were constructed by the common ancestor of all modern passerines. Open cup nests evolved from enclosed domes at least four times independently during early passerine evolution, at least three of which occurred on the Australian continent, yielding several primarily cup-nesting clades that are now widespread and numerically dominant among passerines. Our results show that the ubiquitous and relatively simple cup-shaped nests of many birds today evolved multiple times convergently, suggesting adaptive benefits over earlier roofed designs. © 2017 The Author(s).

Do Predation Rates on Artificial Nests Accurately Reflect Predation Rates on Natural Bird Nests?

Science.gov (United States)

David I. King; Richard M. DeGraaf; Curtice R. Griffin; Thomas J. Maier

1999-01-01

Artificial nests are widely used in avian field studies. However, it is unclear how well predation rates on artificial nests reflect predation rates on natural nests. Therefore, we compared survival rates of artificial nests (unused natural nests baited with House Sparrow eggs) with survival rates of active bird nests in the same habitat at the same sites. Survival...

Influence of Nest Box Color and Release Sites on Osmia lignaria (Hymenoptera: Megachilidae) Reproductive Success in a Commercial Almond Orchard.

Science.gov (United States)

Artz, Derek R; Allan, Matthew J; Wardell, Gordon I; Pitts-Singer, Theresa L

2014-12-01

Intensively managed, commercial orchards offer resources for managed solitary bees within agricultural landscapes and provide a means to study bee dispersal patterns, spatial movement, nest establishment, and reproduction. In 2012, we studied the impact of 1) the color of nest boxes covaried with four nest box density treatments and 2) the number of bee release sites covaried with two nest box density treatments on the reproductive success of Osmia lignaria Say in a California almond orchard pollinated by a mixture of O. lignaria and Apis mellifera L. Nest box color influenced the number of nests, total cells, and cells with male and female brood. More nests and cells were produced in light blue nest boxes than in orange or yellow nest boxes. The covariate nest box density also had a significant effect on brood production. The number of release sites did not affect O. lignaria nesting and reproduction, but the number of cavities in nest boxes influenced reproduction. Overall, the color of nest boxes and their distribution, but not the number of release sites, can greatly affect O. lignaria nest establishment and reproductive success in a commercial almond orchard. The ability to locate nesting sites in a homogenous, large orchard landscape may also be facilitated by the higher frequency of nest boxes with low numbers of cavities, and by the ability to detect certain nest box colors that best contrast with the blooming trees. © 2014 Entomological Society of America.

CAR-T cells: the long and winding road to solid tumors.

Science.gov (United States)

D'Aloia, Maria Michela; Zizzari, Ilaria Grazia; Sacchetti, Benedetto; Pierelli, Luca; Alimandi, Maurizio

2018-02-15

Adoptive cell therapy of solid tumors with reprogrammed T cells can be considered the "next generation" of cancer hallmarks. CAR-T cells fail to be as effective as in liquid tumors for the inability to reach and survive in the microenvironment surrounding the neoplastic foci. The intricate net of cross-interactions occurring between tumor components, stromal and immune cells leads to an ineffective anergic status favoring the evasion from the host's defenses. Our goal is hereby to trace the road imposed by solid tumors to CAR-T cells, highlighting pitfalls and strategies to be developed and refined to possibly overcome these hurdles.

Effect of heterogeneity of nest boxes on occurrence of gregarious nesting in laying hens

DEFF Research Database (Denmark)

Clausen, Tina; Riber, Anja Brinch

2012-01-01

Gregarious nesting, where hens select already occupied nest boxes even when other nest boxes are unoccupied, is an unwanted behaviour in laying hens that may reduce animal welfare and pose a financial cost to the producer. It has been suggested that gregarious nesting is caused by the difficulties...... nesting was higher in experimental groups compared to control groups (P right were higher compared to nest boxes positioned...

LG Solid Oxide Fuel Cell (SOFC) Model Development

Energy Technology Data Exchange (ETDEWEB)

Haberman, Ben [LG Fuel Cell Systems Inc., North Canton, OH (United States); Martinez-Baca, Carlos [LG Fuel Cell Systems Inc., North Canton, OH (United States); Rush, Greg [LG Fuel Cell Systems Inc., North Canton, OH (United States)

2013-05-31

This report presents a summary of the work performed by LG Fuel Cell Systems Inc. during the project LG Solid Oxide Fuel Cell (SOFC) Model Development (DOE Award Number: DE-FE0000773) which commenced on October 1, 2009 and was completed on March 31, 2013. The aim of this project is for LG Fuel Cell Systems Inc. (formerly known as Rolls-Royce Fuel Cell Systems (US) Inc.) (LGFCS) to develop a multi-physics solid oxide fuel cell (SOFC) computer code (MPC) for performance calculations of the LGFCS fuel cell structure to support fuel cell product design and development. A summary of the initial stages of the project is provided which describes the MPC requirements that were developed and the selection of a candidate code, STAR-CCM+ (CD-adapco). This is followed by a detailed description of the subsequent work program including code enhancement and model verification and validation activities. Details of the code enhancements that were implemented to facilitate MPC SOFC simulations are provided along with a description of the models that were built using the MPC and validated against experimental data. The modeling work described in this report represents a level of calculation detail that has not been previously available within LGFCS.

Crystalline structure and microstructural characteristics of the cathode/electrolyte solid oxide half-cells

International Nuclear Information System (INIS)

Chiba, Rubens; Vargas, Reinaldo Azevedo; Andreoli, Marco; Santoro, Thais Aranha de Barros; Seo, Emilia Satoshi Miyamaru

2009-01-01

The solid oxide fuel cell (SOFC) is an electrochemical device generating of electric energy, constituted of cathode, electrolyte and anode; that together they form a unity cell. The study of the solid oxide half-cells consisting of cathode and electrolyte it is very important, in way that is the responsible interface for the reduction reaction of the oxygen. These half-cells are ceramic materials constituted of strontium-doped lanthanum manganite (LSM) for the cathode and yttria-stabilized zirconia (YSZ) for the electrolyte. In this work, two solid oxide half-cells have been manufactured, one constituted of LSM cathode thin film on YSZ electrolyte substrate (LSM - YSZ half-cell), and another constituted of LSM cathode and LSM/YSZ composite cathode thin films on YSZ electrolyte substrate (LSM - LSM/YSZ - YSZ half cell). The cathode/electrolyte solid oxide half-cells were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results have been presented with good adherence between cathode and electrolyte and, LSM and YSZ phases were identified. (author)

Mathematical modeling of solid oxide fuel cells

Science.gov (United States)

Lu, Cheng-Yi; Maloney, Thomas M.

1988-01-01

Development of predictive techniques, with regard to cell behavior, under various operating conditions is needed to improve cell performance, increase energy density, reduce manufacturing cost, and to broaden utilization of various fuels. Such technology would be especially beneficial for the solid oxide fuel cells (SOFC) at it early demonstration stage. The development of computer models to calculate the temperature, CD, reactant distributions in the tubular and monolithic SOFCs. Results indicate that problems of nonuniform heat generation and fuel gas depletion in the tubular cell module, and of size limitions in the monolithic (MOD 0) design may be encountered during FC operation.

Tubular solid oxide fuel cell development program

Energy Technology Data Exchange (ETDEWEB)

Ray, E.R.; Cracraft, C.

1995-12-31

This paper presents an overview of the Westinghouse Solid Oxide Fuel Cell (SOFC) development activities and current program status. The Westinghouse goal is to develop a cost effective cell that can operate for 50,000 to 100,000 hours. Progress toward this goal will be discussed and test results presented for multiple single cell tests which have now successfully exceeded 56,000 hours of continuous power operation at temperature. Results of development efforts to reduce cost and increase power output of tubular SOFCs are described.

SOCTESQA - Solid Oxide Cell and Stack Testing, Safety and Quality Assurance

OpenAIRE

Lang, Michael; Auer, Corinna; Couturier, Karine; Nielsen, Eva Ravn; Mc Phail, Stephen; Kotsionopoulos, Nikolaos; FU, Qingxi; Liu, Qinglin

2015-01-01

For the successful market penetration of high temperature solid oxide fuel/electrolysis cell energy systems it is necessary to increase the quality assurance and the reliable assessment of the corresponding cells and stacks. Therefore in May 2014 the EU-funded project SOCTESQA was launched. Partners from different countries in Europe and one external party from Singapore are working together to develop uniform and industry wide test procedures and programs for solid oxide cell/stack (SOC) ass...

Nest predation increases with parental activity: separating nest site and parental activity effects.

OpenAIRE

Martin, T E; Scott, J; Menge, C

2000-01-01

Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators h...

Solid-state electrochromic cell with anodic iridium oxide film electrodes

International Nuclear Information System (INIS)

Dautremont-Smith, W.C.; Beni, G.; Schiavone, L.M.; Shay, J.L.

1979-01-01

A new solid-state electrochromic cell has been fabricated using an anodic iridium oxide film (AIROF) display electrode. The cell has the symmetric sandwich structure AIROFvertical-barNafionvertical-barAIROF, with the Nafion solid electrolyte opacified by an in situ precipitation technique. A symmetric square-wave voltage of 1.5 V amplitude produces clearly perceivable color changes from pale to dark blue-gray in approx. =1 sec when viewed in diffuse reflection. Good open-circuit optical memory is exhibited:

Nesting bird deterrents for the Federal Republic of Germany glass log storage pad

International Nuclear Information System (INIS)

Mitchell, R.M.

1997-01-01

A proposed storage pad wi11 be constructed in the 200 West Area for the storage of isotopic heat and radiation sources from the Federal Republic of Germany. The pad will be constructed in the southern portion of the Solid Waste Operations Complex near the existing Sodium Storage Pad (Figure 1). Following a biological review by Pacific Northwest National Laboratory (PNNL) personnel (Brandt 1996), it was determined that in order for construction to take place after March 15, 1997, actions would need to be taken to prevent migratory birds from nesting in the project area. Special attention was focused on preventing sage sparrows and loggerhead shrikes, both Hanford Site species of concern (DOE/RL 1996), from nesting in the area. This activity plan details the methods and procedures that will be used to implement these nesting deterrents

Interconnection of bundled solid oxide fuel cells

Science.gov (United States)

Brown, Michael; Bessette, II, Norman F; Litka, Anthony F; Schmidt, Douglas S

2014-01-14

A system and method for electrically interconnecting a plurality of fuel cells to provide dense packing of the fuel cells. Each one of the plurality of fuel cells has a plurality of discrete electrical connection points along an outer surface. Electrical connections are made directly between the discrete electrical connection points of adjacent fuel cells so that the fuel cells can be packed more densely. Fuel cells have at least one outer electrode and at least one discrete interconnection to an inner electrode, wherein the outer electrode is one of a cathode and and anode and wherein the inner electrode is the other of the cathode and the anode. In tubular solid oxide fuel cells the discrete electrical connection points are spaced along the length of the fuel cell.

SOLID STATE ENERGY CONVERSION ALLIANCE DELPHI SOLID OXIDE FUEL CELL

Energy Technology Data Exchange (ETDEWEB)

Steven Shaffer; Sean Kelly; Subhasish Mukerjee; David Schumann; Gail Geiger; Kevin Keegan; John Noetzel; Larry Chick

2003-12-08

The objective of Phase I under this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with the option of piped-in water (Demonstration System A). Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from January 1, 2003 to June 30, 2003, under Department of Energy Cooperative Agreement DE-FC-02NT41246. This report highlights technical results of the work performed under the following tasks: Task 1 System Design and Integration; Task 2 Solid Oxide Fuel Cell Stack Developments; Task 3 Reformer Developments; Task 4 Development of Balance of Plant (BOP) Components; Task 5 Manufacturing Development (Privately Funded); Task 6 System Fabrication; Task 7 System Testing; Task 8 Program Management; and Task 9 Stack Testing with Coal-Based Reformate.

The nest as fortress: Defensive behavior of Polybia emaciata, a mud-nesting eusocial wasp

Directory of Open Access Journals (Sweden)

Sean O'Donnell

2002-02-01

Full Text Available The swarm-founding wasp Polybia emaciata is unusual among eusocial Vespidae because it uses mud, rather than wood pulp, as its primary nest construction material. Polybia emaciata nests are more durable than similarly sized paper nests. We tested the hypothesis that the defensive behavior of this wasp may have been modified to take advantage of their strong nests in defense against vertebrate attacks. We simulated vertebrate disturbances by tapping on, and breathing in, P. emaciata. nests and similarly sized P. occidentalis paper nests in the same location at the same time. Polybia emaciata. responses to disturbance were qualitatively different from those of P. occidentalis. The latter exit the nest and attack, while P. emaciata. workers typically fled or entered the nest, attacking only after repeated and extended disturbances. We conclude that durable nest material may permit predator avoidance behavior in P. emaciata.. We compare the defensive responses of P. emaciata. workers with those of other swarm-founding Vespidae, and discuss several selective forces that could cause the evolution of species variation in nest defense behavior.

The thermal environment of the nest affects body and cell size in the solitary red mason bee (Osmia bicornis L.).

Science.gov (United States)

Kierat, Justyna; Szentgyörgyi, Hajnalka; Czarnoleski, Marcin; Woyciechowski, Michał

2017-08-01

Many ectotherms grow larger at lower temperatures than at higher temperatures. This pattern, known as the temperature-size rule, is often accompanied by plastic changes in cell size, which can mechanistically explain the thermal dependence of body size. However, the theory predicts that thermal plasticity in cell size has adaptive value for ectotherms because there are different optimal cell-membrane-to-cell-volume ratios at different temperatures. At high temperatures, the demand for oxygen is high; therefore, a large membrane surface of small cells is beneficial because it allows high rates of oxygen transport into the cell. The metabolic costs of maintaining membranes become more important at low temperatures than at high temperatures, which favours large cells. In a field experiment, we manipulated the thermal conditions inside nests of the red mason bee, a solitary bee that does not regulate the temperature in its nests and whose larvae develop under ambient conditions. We assessed the effect of temperature on body mass and ommatidia size (our proxy of cell size). The body and cell sizes decreased in response to a higher mean temperature and greater temperature fluctuations. This finding is in accordance with predictions of the temperature-size rule and optimal cell size theory and suggests that both the mean temperature and the magnitude of temperature fluctuations are important for determining body and cell sizes. Additionally, we observed that males of the red mason bee tend to have larger ommatidia in relation to their body mass than females, which might play an important role during mating flight. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cavity Nesting Birds

Science.gov (United States)

Virgil E. Scott; Keith E. Evans; David R. Patton; Charles P. Stone

1977-01-01

Many species of cavity-nesting birds have declined because of habitat reduction. In the eastern United States, where primeval forests are gone, purple martins depend almost entirely on man-made nesting structures (Allen and Nice 1952). The hole-nesting population of peregrine falcons disappeared with the felling of the giant trees upon which they depended (Hickey and...

Nest predators of open and cavity nesting birds in oak woodlands

Science.gov (United States)

Kathryn L. Purcell; Jared Verner

1999-01-01

Camera setups revealed at least three species of rodents and seven species of birds as potential predators at artificial open nests. Surprisingly, among avian predators identified at open nests, one third were Bullock's Orioles (Icterus bullockii). Two rodent species and three bird species were potential predators at artificial cavity nests. This high predator...

Direct Carbon Fuel Cell System Utilizing Solid Carbonaceous Fuels

Energy Technology Data Exchange (ETDEWEB)

Turgut Gur

2010-04-30

This 1-year project has achieved most of its objective and successfully demonstrated the viability of the fluidized bed direct carbon fuel cell (FB-DCFC) approach under development by Direct Carbon technologies, LLC, that utilizes solid carbonaceous fuels for power generation. This unique electrochemical technology offers high conversion efficiencies, produces proportionately less CO{sub 2} in capture-ready form, and does not consume or require water for gasification. FB-DCFC employs a specialized solid oxide fuel cell (SOFC) arrangement coupled to a Boudouard gasifier where the solid fuel particles are fluidized and reacted by the anode recycle gas CO{sub 2}. The resulting CO is electrochemically oxidized at the anode. Anode supported SOFC structures employed a porous Ni cermet anode layer, a dense yttria stabilized zirconia membrane, and a mixed conducting porous perovskite cathode film. Several kinds of untreated solid fuels (carbon and coal) were tested in bench scale FBDCFC prototypes for electrochemical performance and stability testing. Single cells of tubular geometry with active areas up to 24 cm{sup 2} were fabricated. The cells achieved high power densities up to 450 mW/cm{sup 2} at 850 C using a low sulfur Alaska coal char. This represents the highest power density reported in the open literature for coal based DCFC. Similarly, power densities up to 175 mW/cm{sup 2} at 850 C were demonstrated with carbon. Electrical conversion efficiencies for coal char were experimentally determined to be 48%. Long-term stability of cell performance was measured under galvanostatic conditions for 375 hours in CO with no degradation whatsoever, indicating that carbon deposition (or coking) does not pose any problems. Similar cell stability results were obtained in coal char tested for 24 hours under galvanostatic conditions with no sign of sulfur poisoning. Moreover, a 50-cell planar stack targeted for 1 kW output was fabricated and tested in 95% CO (balance CO{sub 2

Modeling nest survival of cavity-nesting birds in relation to postfire salvage logging

Science.gov (United States)

Vicki Saab; Robin E. Russell; Jay Rotella; Jonathan G. Dudley

2011-01-01

Salvage logging practices in recently burned forests often have direct effects on species associated with dead trees, particularly cavity-nesting birds. As such, evaluation of postfire management practices on nest survival rates of cavity nesters is necessary for determining conservation strategies. We monitored 1,797 nests of 6 cavity-nesting bird species: Lewis'...

Triangular Nests!

Science.gov (United States)

Powell, R. I.

2002-01-01

Shows how integer-sided triangles can be nested, each nest having a single enclosing isosceles triangle. Brings to light what can be seen as a relatively simple generalization of Pythagoras' theorem, a result that should be readily accessible to many secondary school pupils. (Author/KHR)

Nest-site habitat of cavity-nesting birds at the San Joaquin Experimental Range

Science.gov (United States)

Kathryn L. Purcell; Jared. Verner

2008-01-01

Detailed information about the nesting habitats of birds, including those needed for successful nesting, can provide a better understanding of the ecological factors that permit coexistence of different species and may aid in conservation efforts. From 1989 through 1994, we studied the nesting habitat of secondary cavity-nesting birds in oak woodlands at the San...

Direct Coal Oxidation in Modified Solid Oxide Fuel Cells

DEFF Research Database (Denmark)

Deleebeeck, Lisa; Gil, Vanesa; Ippolito, Davide

2017-01-01

Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon-carbonate s......Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon......-carbonate slurry or anode layer. The nature of the coal affects both open circuit voltage and power output. Highest OCV and power densities were observed for bituminous coal and by adding manganese oxide or praseodymium-doped ceria to the carbon/carbonate mixture. Comparing the carbon black fueled performance...... bituminous coal (73 mW/cm2)....

Spawning chronology, nest site selection and nest success of smallmouth bass during benign streamflow conditions

Science.gov (United States)

Dauwalter, D.C.; Fisher, W.L.

2007-01-01

We documented the nesting chronology, nest site selection and nest success of smallmouth bass Micropterus dolomieu in an upstream (4th order) and downstream (5th order) reach of Baron Fork Creek, Oklahoma. Males started nesting in mid-Apr. when water temperatures increased to 16.9 C upstream, and in late-Apr. when temperatures increased to 16.2 C downstream. Streamflows were low (77% upstream to 82% downstream of mean Apr. streamflow, and 12 and 18% of meanjun. streamflow; 47 and 55 y of record), and decreased throughout the spawning period. Larger males nested first upstream, as has been observed in other populations, but not downstream. Upstream, progeny in 62 of 153 nests developed to swim-up stage. Downstream, progeny in 31 of 73 nests developed to swim-up. Nesting densities upstream (147/km) and downstream (100/km) were both higher than any densities previously reported. Males selected nest sites with intermediate water depths, low water velocity and near cover, behavior that is typical of smallmouth bass. Documented nest failures resulted from human disturbance, angling, and longear sunfish predation. Logistic exposure models showed that water velocity at the nest was negatively related and length of the guarding male was positively related to nest success upstream. Male length and number of degree days were both positively related to nest success downstream. Our results, and those of other studies, suggest that biological factors account for most nest failures during benign (stable, low flow) streamflow conditions, whereas nest failures attributed to substrate mobility or nest abandonment dominate when harsh streamflow conditions (spring floods) coincide with the spawning season.

Cavity-nesting bird use of nest boxes in vineyards of central-coast California

Science.gov (United States)

Daniel P. Mummert; Laura Baines; William D. Tietje

2002-01-01

Oak woodland habitat is being degraded or replaced by vineyards in many areas of central-coastal California. Oak woodlands are home to many insectivorous, cavity-nesting birds that would be beneficial in and around vineyards. During March to June 2001, we used bluebird nest boxes to study nest box use and productivity of cavity-nesting birds in vineyards versus...

Livestock grazing and trampling of birds' nests: An experiment using artificial nests

OpenAIRE

Mandema, Freek S.; Tinbergen, Joost M.; Ens, Bruno J.; Bakker, Jan P.

2013-01-01

The purpose of this study is to experimentally determine the differences between four grazing treatments on the trampling of nests. Additionally, we examine to what extent the trampling probability of nests is higher close to a source of fresh water. We compare the trampling of artificial nests in five different grazing treatments in an experimental design. We use buried clay pigeon targets as artificial mimics of bird nests to obtain reliable estimates of trampling risk and compare these wit...

Flown The Nest

OpenAIRE

Sebbane, Nathalie

2012-01-01

Lorsque le quotidien régional, The Champion, commence à publier Flown The Nest en 1972 sous forme d’épisodes, Bird’s Nest Soup est déjà en vente, et la troisième partie de l’autobiographie d’Hanna, Housekeeper At Large, est sous presse. L’édition de 2009 contient Flown The Nest et Housekeeper at Large. Dans Bird’s Nest Soup, Hanna Greally racontait les dix-huit années de sa vie passées au sein d’un hôpital psychiatrique. Les raisons pour lesquelles elle y avait été enfermée, à la demande de s...

From neurons to nests: nest-building behaviour as a model in behavioural and comparative neuroscience.

Science.gov (United States)

Hall, Zachary J; Meddle, Simone L; Healy, Susan D

Despite centuries of observing the nest building of most extant bird species, we know surprisingly little about how birds build nests and, specifically, how the avian brain controls nest building. Here, we argue that nest building in birds may be a useful model behaviour in which to study how the brain controls behaviour. Specifically, we argue that nest building as a behavioural model provides a unique opportunity to study not only the mechanisms through which the brain controls behaviour within individuals of a single species but also how evolution may have shaped the brain to produce interspecific variation in nest-building behaviour. In this review, we outline the questions in both behavioural and comparative neuroscience that nest building could be used to address, summarize recent findings regarding the neurobiology of nest building in lab-reared zebra finches and across species building different nest structures, and suggest some future directions for the neurobiology of nest building.

Avoiding the nest : responses of field sparrows to the threat of nest predation

Science.gov (United States)

Dirk E. Burhans

2000-01-01

Nest predation is a major source of reproductive failure in birds (Ricklefs 1969, Martin 1992). Birds confronted with an enemy near the nest may use behaviors to deter the prospect of nest predation. The benefits of nest defense have been shown for many agressive species (Martin 1992), but smaller birds that cannot deter predators may need to resort to other behaviors...

Electrochemical characterisation of solid oxide cell electrodes for hydrogen production

DEFF Research Database (Denmark)

Bernuy-Lopez, Carlos; Knibbe, Ruth; He, Zeming

2011-01-01

Oxygen electrodes and steam electrodes are designed and tested to develop improved solid oxide electrolysis cells for H2 production with the cell support on the oxygen electrode. The electrode performance is evaluated by impedance spectroscopy testing of symmetric cells at open circuit voltage (OCV...

Challenges and prospects of chimeric antigen receptor T cell therapy in solid tumors.

Science.gov (United States)

Jindal, Vishal; Arora, Ena; Gupta, Sorab

2018-05-05

Chimeric antigen receptor (CAR) T cell therapy is a novel and innovative immunotherapy. CAR-T cells are genetically engineered T cells, carrying MHC independent specific antigen receptor and co-stimulatory molecule which can activate an immune response to a cancer specific antigen. This therapy showed great results in hematological malignancies but were unable to prove their worth in solid tumors. Likely reasons for their failure are lack of antigens, poor trafficking, and hostile tumor microenvironment. Excessive amount of research is going on to improve the efficacy of CAR T cell therapy in solid tumors. In this article, we will discuss the challenges faced in improving the outcome of CAR T cell therapy in solid tumors and various strategies adopted to curb them.

FLAG-tagged CD19-specific CAR-T cells eliminate CD19-bearing solid tumor cells in vitro and in vivo.

Science.gov (United States)

Berahovich, Robert; Xu, Shirley; Zhou, Hua; Harto, Hizkia; Xu, Qumiao; Garcia, Andres; Liu, Fenyong; Golubovskaya, Vita M; Wu, Lijun

2017-06-01

Autologous T cells expressing chimeric antigen receptors (CARs) specific for CD19 have demonstrated remarkable efficacy as therapeutics for B cell malignancies. In the present study, we generated FLAG-tagged CD19-specific CAR-T cells (CD19-FLAG) and compared them to their non-tagged counterparts for their effects on solid and hematological cancer cells in vitro and in vivo . For solid tumors, we used HeLa cervical carcinoma cells engineered to overexpress CD19 (HeLa-CD19), and for hematological cancer we used Raji Burkitt's lymphoma cells, which endogenously express CD19. Like non-tagged CD19 CAR-T cells, CD19-FLAG CAR-T cells expanded in culture >100-fold and exhibited potent cytolytic activity against both HeLa-CD19 and Raji cells in vitro . CD19-FLAG CAR-T cells also secreted significantly more IFN-gamma and IL-2 than the control T cells. In vivo , CD19-FLAG CAR-T cells significantly blocked the growth of HeLa-CD19 solid tumors, increased tumor cleaved caspase-3 levels, and expanded systemically. CD19-FLAG CAR-T cells also significantly reduced Raji tumor burden and extended mouse survival. These results demonstrate the strong efficacy of FLAG-tagged CD19 CAR-T cells in solid and hematological cancer models.

Using Artificial Nests to Study Nest Predation in Birds

Science.gov (United States)

Belthoff, James R.

2005-01-01

A simple and effective field exercise that demonstrates factors affecting predation on bird nests is described. With instructor guidance, students in high school biology or college-level biology, ecology, animal behavior, wildlife management or ornithology laboratory courses can collaborate to design field experiments related to nest depredation.

Solid-State NMR on bacterial cells: selective cell wall signal enhancement and resolution improvement using dynamic nuclear polarization

International Nuclear Information System (INIS)

Takahashi, Hiroki; Bardet, Michel; De Paepe, Gael; Hediger, Sabine; Ayala, Isabel; Simorre, Jean-Pierre

2013-01-01

Dynamic nuclear polarization (DNP) enhanced solid-state nuclear magnetic resonance (NMR) has recently emerged as a powerful technique for the study of material surfaces. In this study, we demonstrate its potential to investigate cell surface in intact cells. Using Bacillus subtilis bacterial cells as an example, it is shown that the polarizing agent 1-(TEMPO-4-oxy)-3-(TEMPO-4-amino)propan-2-ol (TOTAPOL) has a strong binding affinity to cell wall polymers (peptidoglycan). This particular interaction is thoroughly investigated with a systematic study on extracted cell wall materials, disrupted cells, and entire cells, which proved that TOTAPOL is mainly accumulating in the cell wall. This property is used on one hand to selectively enhance or suppress cell wall signals by controlling radical concentrations and on the other hand to improve spectral resolution by means of a difference spectrum. Comparing DNP-enhanced and conventional solid-state NMR, an absolute sensitivity ratio of 24 was obtained on the entire cell sample. This important increase in sensitivity together with the possibility of enhancing specifically cell wall signals and improving resolution really opens new avenues for the use of DNP-enhanced solid-state NMR as an on-cell investigation tool. (authors)

Solid-state NMR on bacterial cells: selective cell wall signal enhancement and resolution improvement using dynamic nuclear polarization.

Science.gov (United States)

Takahashi, Hiroki; Ayala, Isabel; Bardet, Michel; De Paëpe, Gaël; Simorre, Jean-Pierre; Hediger, Sabine

2013-04-03

Dynamic nuclear polarization (DNP) enhanced solid-state nuclear magnetic resonance (NMR) has recently emerged as a powerful technique for the study of material surfaces. In this study, we demonstrate its potential to investigate cell surface in intact cells. Using Bacillus subtilis bacterial cells as an example, it is shown that the polarizing agent 1-(TEMPO-4-oxy)-3-(TEMPO-4-amino)propan-2-ol (TOTAPOL) has a strong binding affinity to cell wall polymers (peptidoglycan). This particular interaction is thoroughly investigated with a systematic study on extracted cell wall materials, disrupted cells, and entire cells, which proved that TOTAPOL is mainly accumulating in the cell wall. This property is used on one hand to selectively enhance or suppress cell wall signals by controlling radical concentrations and on the other hand to improve spectral resolution by means of a difference spectrum. Comparing DNP-enhanced and conventional solid-state NMR, an absolute sensitivity ratio of 24 was obtained on the entire cell sample. This important increase in sensitivity together with the possibility of enhancing specifically cell wall signals and improving resolution really opens new avenues for the use of DNP-enhanced solid-state NMR as an on-cell investigation tool.

Solid Oxide Fuel Cell Systems PVL Line

International Nuclear Information System (INIS)

Shearer, Susan; Rush, Gregory

2012-01-01

In July 2010, Stark State College (SSC), received Grant DE-EE0003229 from the U.S. Department of Energy (DOE), Golden Field Office, for the development of the electrical and control systems, and mechanical commissioning of a unique 20kW scale high-pressure, high temperature, natural gas fueled Stack Block Test System (SBTS). SSC worked closely with subcontractor, Rolls-Royce Fuel Cell Systems (US) Inc. (RRFCS) over a 13 month period to successfully complete the project activities. This system will be utilized by RRFCS for pre-commercial technology development and training of SSC student interns. In the longer term, when RRFCS is producing commercial products, SSC will utilize the equipment for workforce training. In addition to DOE Hydrogen, Fuel Cells, and Infrastructure Technologies program funding, RRFCS internal funds, funds from the state of Ohio, and funding from the DOE Solid State Energy Conversion Alliance (SECA) program have been utilized to design, develop and commission this equipment. Construction of the SBTS (mechanical components) was performed under a Grant from the State of Ohio through Ohio's Third Frontier program (Grant TECH 08-053). This Ohio program supported development of a system that uses natural gas as a fuel. Funding was provided under the Department of Energy (DOE) Solid-state Energy Conversion Alliance (SECA) program for modifications required to test on coal synthesis gas. The subject DOE program provided funding for the electrical build, control system development and mechanical commissioning. Performance testing, which includes electrical commissioning, was subsequently performed under the DOE SECA program. Rolls-Royce Fuel Cell Systems is developing a megawatt-scale solid oxide fuel cell (SOFC) stationary power generation system. This system, based on RRFCS proprietary technology, is fueled with natural gas, and operates at elevated pressure. A critical success factor for development of the full scale system is the capability to

On the intrinsic transient capability and limitations of solid oxide fuel cell systems

OpenAIRE

Mueller, F; Jabbari, F; Brouwer, J

2009-01-01

The intrinsic transient performance capability and limitation of integrated solid oxide fuel cell (SOFC) systems is evaluated based on the system balance-of-plant response and fuel cell operating requirements (i.e., allowable deviation from nominal operation). Specifically, non-dimensional relations are derived from conservation principles that quantify the maximum instantaneous current increase that a solid oxide fuel cell system can safely manage based on (1) the desired fuel cell operating...

In utero bisphenol A exposure disrupts germ cell nest breakdown and reduces fertility with age in the mouse

Energy Technology Data Exchange (ETDEWEB)

Wang, Wei, E-mail: weiwang2@illinois.edu; Hafner, Katlyn S., E-mail: katlynhafner@gmail.com; Flaws, Jodi A., E-mail: jflaws@illinois.edu

2014-04-15

Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestational day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. - Highlights: • In utero BPA exposure inhibits germ cell nest breakdown in female mouse offspring. • In utero BPA exposure alters expression of apoptosis regulators in the ovaries of mouse offspring. • In utero BPA exposure advances first estrus age and alters cyclicity in mouse offspring. • In utero BPA exposure causes various fertility problems in

In utero bisphenol A exposure disrupts germ cell nest breakdown and reduces fertility with age in the mouse

International Nuclear Information System (INIS)

Wang, Wei; Hafner, Katlyn S.; Flaws, Jodi A.

2014-01-01

Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestational day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. - Highlights: • In utero BPA exposure inhibits germ cell nest breakdown in female mouse offspring. • In utero BPA exposure alters expression of apoptosis regulators in the ovaries of mouse offspring. • In utero BPA exposure advances first estrus age and alters cyclicity in mouse offspring. • In utero BPA exposure causes various fertility problems in

Direct Coal Oxidation in Modified Solid Oxide Fuel Cells

DEFF Research Database (Denmark)

Deleebeeck, Lisa; Gil, Vanesa; Ippolito, Davide

2015-01-01

Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon-carbonate s......Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon......-carbonate slurry or anode layer. The nature of the coal affects both open circuit voltage and power output. Highest OCV and power densities were observed for bituminous coal and by adding manganese oxide or praseodymium-doped ceria to the carbon/carbonate mixture. Comparing the carbon black fueled performance...... bituminous coal (73 mW/cm2). © 2015 ECS - The Electrochemical Society...

Livestock grazing and trampling of birds' nests : An experiment using artificial nests

NARCIS (Netherlands)

Mandema, Freek S.; Tinbergen, Joost M.; Ens, Bruno J.; Bakker, Jan P.

The purpose of this study is to experimentally determine the differences between four grazing treatments on the trampling of nests. Additionally, we examine to what extent the trampling probability of nests is higher close to a source of fresh water. We compare the trampling of artificial nests in

Nested and Hierarchical Archimax copulas

KAUST Repository

Hofert, Marius

2017-07-03

The class of Archimax copulas is generalized to nested and hierarchical Archimax copulas in several ways. First, nested extreme-value copulas or nested stable tail dependence functions are introduced to construct nested Archimax copulas based on a single frailty variable. Second, a hierarchical construction of d-norm generators is presented to construct hierarchical stable tail dependence functions and thus hierarchical extreme-value copulas. Moreover, one can, by itself or additionally, introduce nested frailties to extend Archimax copulas to nested Archimax copulas in a similar way as nested Archimedean copulas extend Archimedean copulas. Further results include a general formula for the density of Archimax copulas.

Nested and Hierarchical Archimax copulas

KAUST Repository

Hofert, Marius; Huser, Raphaë l; Prasad, Avinash

2017-01-01

The class of Archimax copulas is generalized to nested and hierarchical Archimax copulas in several ways. First, nested extreme-value copulas or nested stable tail dependence functions are introduced to construct nested Archimax copulas based on a single frailty variable. Second, a hierarchical construction of d-norm generators is presented to construct hierarchical stable tail dependence functions and thus hierarchical extreme-value copulas. Moreover, one can, by itself or additionally, introduce nested frailties to extend Archimax copulas to nested Archimax copulas in a similar way as nested Archimedean copulas extend Archimedean copulas. Further results include a general formula for the density of Archimax copulas.

Nest site characteristics, nesting movements, and lack of long-term nest site fidelity in Agassiz's desert tortoises at a wind energy facility in southern California

Science.gov (United States)

Lovich, Jeffrey E.; Agha, Mickey; Yackulic, Charles B.; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Ennen, Joshua R.; Arundel, Terry R.; Austin, Meaghan

2014-01-01

Nest site selection has important consequences for maternal and offspring survival and fitness. Females of some species return to the same nesting areas year after year. We studied nest site characteristics, fidelity, and daily pre-nesting movements in a population of Agassiz’s desert tortoises (Gopherus agassizii) at a wind energy facility in southern California during two field seasons separated by over a decade. No females returned to the same exact nest site within or between years but several nested in the same general area. However, distances between first and second clutches within a year (2000) were not significantly different from distances between nests among years (2000 and 2011) for a small sample of females, suggesting some degree of fidelity within their normal activity areas. Environmental attributes of nest sites did not differ significantly among females but did among years due largely to changes in perennial plant structure as a result of multiple fires. Daily pre-nesting distances moved by females decreased consistently from the time shelled eggs were first visible in X-radiographs until oviposition, again suggesting some degree of nest site selection. Tortoises appear to select nest sites that are within their long-term activity areas, inside the climate-moderated confines of one of their self-constructed burrows, and specifically, at a depth in the burrow that minimizes exposure of eggs and embryos to lethal incubation temperatures. Nesting in “climate-controlled” burrows and nest guarding by females relaxes some of the constraints that drive nest site selection in other oviparous species.

Trap-nests used by Centris (Heterocentris) terminata Smith (Hymenoptera: Apidae, Centridini) at secondary Atlantic Forest fragments, in Salvador, Bahia State

International Nuclear Information System (INIS)

Drummmont, Patricia; Viana, Blandina F.; Silva, Fabiana O. da

2008-01-01

Ninety-five nests of Centris (Heterocentris) terminata Smith were collected in trap nests, during November/2001 and January/2003, at two fragments (PZGV e CFO-UFBA) of secondary Atlantic Forest, in Salvador, Bahia State (13 deg 01' W and 38 deg 30' S). The highest nest frequencies occurred from December to February (summer), with no nests foundations from August to October (winter - early spring). Two-hundred eight adults emerged from 347 brood cells, being 164 males and 116 females (1: 0.42). During the study period sex ratio was male biased (χ 2 = 9.342; gl = 10; P < 0.05). C. terminata nested in holes with diameters 6, 8, 10 mm, but 84,2% were constructed in 8 and 10 mm. nests had one to seven cells arranged in a linear series with the cell's partitions built with a mixture of sand and resin or oil. Male is significantly smaller than female, which emerges from the first cells constructed. Immature mortality occurred in 14.1% of brood cells (n 49), of which 13.0% were due fail in development and 1.2% due to parasitism of Coelioxys sp. (Hymenoptera: Megachilidae) e Tetraonyx sp. (Coleoptera: Meloidae). In the study site, weather, mainly pluviosity, rather than natural enemies influenced seasonal population abundance. The long period of nesting activity, local abundance and usage of trap nests, suggest the potential of C. terminata for management aiming at pollination of native and cultivated plants. (author)

Nest site attributes and temporal patterns of northern flicker nest loss: effects of predation and competition.

Science.gov (United States)

Fisher, Ryan J; Wiebe, Karen L

2006-04-01

To date, most studies of nest site selection have failed to take into account more than one source of nest loss (or have combined all sources in one analysis) when examining nest site characteristics, leaving us with an incomplete understanding of the potential trade-offs that individuals may face when selecting a nest site. Our objectives were to determine whether northern flickers (Colaptes auratus) may experience a trade-off in nest site selection in response to mammalian nest predation and nest loss to a cavity nest competitor (European starling, Sturnus vulgaris). We also document within-season temporal patterns of these two sources of nest loss with the hypothesis that flickers may also be constrained in the timing of reproduction under both predatory and competitive influence. Mammalian predators frequently depredated flicker nests that were: lower to the ground, less concealed by vegetation around the cavity entrance and at the base of the nest tree, closer to coniferous forest edges and in forest clumps with a high percentage of conifer content. Proximity to coniferous edges or coniferous trees increased the probability of nest predation, but nests near conifers were less likely to be lost to starlings. Flickers may thus face a trade-off in nest site selection with respect to safety from predators or competitors. Models suggested that peaks of nest predation and nest loss to eviction occurred at the same time, although a competing model suggested that the peak of nest loss to starlings occurred 5 days earlier than the peak of mammalian predation. Differences in peaks of mammalian predation and loss to starlings may constrain any adjustment in clutch initiation date by flickers to avoid one source of nest loss.

Chimeric-antigen receptor T (CAR-T) cell therapy for solid tumors: challenges and opportunities.

Science.gov (United States)

Xia, An-Liang; Wang, Xiao-Chen; Lu, Yi-Jun; Lu, Xiao-Jie; Sun, Beicheng

2017-10-27

Chimeric antigen receptor (CAR)-engineered T cells (CAR-T cells) have been shown to have unprecedented efficacy in B cell malignancies, most notably in B cell acute lymphoblastic leukemia (B-ALL) with up to a 90% complete remission rate using anti-CD19 CAR-T cells. However, CAR T-cell therapy for solid tumors currently is faced with numerous challenges such as physical barriers, the immunosuppressive tumor microenvironment and the specificity and safety. The clinical results in solid tumors have been much less encouraging, with multiple cases of toxicity and a lack of therapeutic response. In this review, we will discuss the current stats and challenges of CAR-T cell therapy for solid tumors, and propose possibl e solutions and future perspectives.

Nest marking behavior and chemical composition of olfactory cues involved in nest recognition in Megachile rotundata.

Science.gov (United States)

Guédot, Christelle; Buckner, James S; Hagen, Marcia M; Bosch, Jordi; Kemp, William P; Pitts-Singer, Theresa L

2013-08-01

In-nest observations of the solitary bee, Megachile rotundata (F.), revealed that nesting females apply olfactory cues to nests for nest recognition. On their way in and out of the nest, females drag the abdomen along the entire length of the nest, and sometimes deposit fluid droplets from the tip of the abdomen. The removal of bee-marked sections of the nest resulted in hesitation and searching behavior by females, indicating the loss of olfactory cues used for nest recognition. Chemical analysis of female cuticles and the deposits inside marked nesting tubes revealed the presence of hydrocarbons, wax esters, fatty aldehydes, and fatty alcohol acetate esters. Chemical compositions were similar across tube samples, but proportionally different from cuticular extracts. These findings reveal the importance of lipids as chemical signals for nest recognition and suggest that the nest-marking cues are derived from a source in addition to, or other than, the female cuticle.

Buteo Nesting Ecology: Evaluating Nesting of Swainson's Hawks in the Northern Great Plains.

Science.gov (United States)

Inselman, Will M; Datta, Shubham; Jenks, Jonathan A; Jensen, Kent C; Grovenburg, Troy W

2015-01-01

Swainson's hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson's hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson's hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, SDist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%-42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson's hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson's hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson's hawks arriving to the breeding grounds.

Integration of a municipal solid waste gasification plant with solid oxide fuel cell and gas turbine

DEFF Research Database (Denmark)

Bellomare, Filippo; Rokni, Masoud

2013-01-01

An interesting source of producing energy with low pollutants emission and reduced environmental impact are the biomasses; particularly using Municipal Solid Waste (MSW) as fuel, can be a competitive solution not only to produce energy with negligible costs but also to decrease the storage...... in landfills. A Municipal Solid Waste Gasification Plant Integrated with Solid Oxide Fuel Cell (SOFC) and Gas Turbine (GT) has been studied and the plant is called IGSG (Integrated Gasification SOFC and GT). Gasification plant is fed by MSW to produce syngas by which the anode side of an SOFC is fed wherein...

Strength of Anode‐Supported Solid Oxide Fuel Cells

DEFF Research Database (Denmark)

Faes, A.; Frandsen, Henrik Lund; Kaiser, Andreas

2011-01-01

Nickel oxide and yttria doped zirconia composite strength is crucial for anode‐supported solid oxide fuel cells, especially during transient operation, but also for the initial stacking process, where cell curvature after sintering can cause problems. This work first compares tensile and ball....... Even though the electrolyte is to the tensile side, it is found that the anode support fails due to the thermo‐mechanical residual stresses....

Nested structures approach in designing an isotropic negative-index material for infrared

DEFF Research Database (Denmark)

Andryieuski, Andrei; Malureanu, Radu; Lavrinenko, Andrei

2009-01-01

We propose a new generic approach for designing isotropic metamaterial with nested cubic structures. As an example, a three-dimensional isotropic unit cell design "Split Cube in Cage" (SCiC) is shown to exhibit an effective negative refractive index on infrared wavelengths. We report on the refra......We propose a new generic approach for designing isotropic metamaterial with nested cubic structures. As an example, a three-dimensional isotropic unit cell design "Split Cube in Cage" (SCiC) is shown to exhibit an effective negative refractive index on infrared wavelengths. We report...

Solid Polymer Fuel Cells. Electrode and membrane performance studies

Energy Technology Data Exchange (ETDEWEB)

Moeller-Holst, S.

1996-12-31

This doctoral thesis studies aspects of fuel cell preparation and performance. The emphasis is placed on preparation and analysis of low platinum-loading solid polymer fuel cell (SPEC) electrodes. A test station was built and used to test cells within a wide range of real operating conditions, 40-150{sup o}C and 1-10 bar. Preparation and assembling equipment for single SPFCs was designed and built, and a new technique of spraying the catalyst layer directly onto the membrane was successfully demonstrated. Low Pt-loading electrodes (0.1 mg Pt/cm{sup 2}) prepared by the new technique exhibited high degree of catalyst utilization. The performance of single cells holding these electrodes is comparable to state-of-the-art SPFCs. Potential losses in single cell performance are ascribed to irreversibilities by analysing the efficiency of the Solid Oxide Fuel Cell by means of the second law of thermodynamics. The water management in membranes is discussed for a model system and the results are relevant to fuel cell preparation and performance. The new spray deposition technique should be commercially interesting as it involves few steps as well as techniques that are adequate for larger scale production. 115 refs., 43 figs., 18 tabs.

Solid Polymer Fuel Cells. Electrode and membrane performance studies

Energy Technology Data Exchange (ETDEWEB)

Moeller-Holst, S

1997-12-31

This doctoral thesis studies aspects of fuel cell preparation and performance. The emphasis is placed on preparation and analysis of low platinum-loading solid polymer fuel cell (SPEC) electrodes. A test station was built and used to test cells within a wide range of real operating conditions, 40-150{sup o}C and 1-10 bar. Preparation and assembling equipment for single SPFCs was designed and built, and a new technique of spraying the catalyst layer directly onto the membrane was successfully demonstrated. Low Pt-loading electrodes (0.1 mg Pt/cm{sup 2}) prepared by the new technique exhibited high degree of catalyst utilization. The performance of single cells holding these electrodes is comparable to state-of-the-art SPFCs. Potential losses in single cell performance are ascribed to irreversibilities by analysing the efficiency of the Solid Oxide Fuel Cell by means of the second law of thermodynamics. The water management in membranes is discussed for a model system and the results are relevant to fuel cell preparation and performance. The new spray deposition technique should be commercially interesting as it involves few steps as well as techniques that are adequate for larger scale production. 115 refs., 43 figs., 18 tabs.

NiF2/NaF:CaF2/Ca Solid-State High-Temperature Battery Cells

Science.gov (United States)

West, William; Whitacre, Jay; DelCastillo, Linda

2009-01-01

Experiments and theoretical study have demonstrated the promise of all-solid-state, high-temperature electrochemical battery cells based on NiF2 as the active cathode material, CaF2 doped with NaF as the electrolyte material, and Ca as the active anode material. These and other all-solid-state cells have been investigated in a continuing effort to develop batteries for instruments that must operate in environments much hotter than can be withstood by ordinary commercially available batteries. Batteries of this type are needed for exploration of Venus (where the mean surface temperature is about 450 C), and could be used on Earth for such applications as measuring physical and chemical conditions in geothermal wells and oil wells. All-solid-state high-temperature power cells are sought as alternatives to other high-temperature power cells based, variously, on molten anodes and cathodes or molten eutectic salt electrolytes. Among the all-solid-state predecessors of the present NiF2/NaF:CaF2/Ca cells are those described in "Solid-State High-Temperature Power Cells" (NPO-44396), NASA Tech Briefs, Vol. 32, No. 5 (May 2008), page 40. In those cells, the active cathode material is FeS2, the electrolyte material is a crystalline solid solution of equimolar amounts of Li3PO4 and LiSiO4, and the active anode material is Li contained within an alloy that remains solid in the intended high operational temperature range.

Engineered Breast Cancer Cell Spheroids Reproduce Biologic Properties of Solid Tumors.

Science.gov (United States)

Ham, Stephanie L; Joshi, Ramila; Luker, Gary D; Tavana, Hossein

2016-11-01

Solid tumors develop as 3D tissue constructs. As tumors grow larger, spatial gradients of nutrients and oxygen and inadequate diffusive supply to cells distant from vasculature develops. Hypoxia initiates signaling and transcriptional alterations to promote survival of cancer cells and generation of cancer stem cells (CSCs) that have self-renewal and tumor-initiation capabilities. Both hypoxia and CSCs are associated with resistance to therapies and tumor relapse. This study demonstrates that 3D cancer cell models, known as tumor spheroids, generated with a polymeric aqueous two-phase system (ATPS) technology capture these important biological processes. Similar to solid tumors, spheroids of triple negative breast cancer cells deposit major extracellular matrix proteins. The molecular analysis establishes presence of hypoxic cells in the core region and expression of CSC gene and protein markers including CD24, CD133, and Nanog. Importantly, these spheroids resist treatment with chemotherapy drugs. A combination treatment approach using a hypoxia-activated prodrug, TH-302, and a chemotherapy drug, doxorubicin, successfully targets drug resistant spheroids. This study demonstrates that ATPS spheroids recapitulate important biological and functional properties of solid tumors and provide a unique model for studies in cancer research. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sharp-Tailed Grouse Nest Survival and Nest Predator Habitat Use in North Dakota's Bakken Oil Field.

Directory of Open Access Journals (Sweden)

Paul C Burr

Full Text Available Recent advancements in extraction technologies have resulted in rapid increases of gas and oil development across the United States and specifically in western North Dakota. This expansion of energy development has unknown influences on local wildlife populations and the ecological interactions within and among species. Our objectives for this study were to evaluate nest success and nest predator dynamics of sharp-tailed grouse (Tympanuchus phasianellus in two study sites that represented areas of high and low energy development intensities in North Dakota. During the summers of 2012 and 2013, we monitored 163 grouse nests using radio telemetry. Of these, 90 nests also were monitored using miniature cameras to accurately determine nest fates and identify nest predators. We simultaneously conducted predator surveys using camera scent stations and occupancy modeling to estimate nest predator occurrence at each site. American badgers (Taxidea taxus and striped skunks (Mephitis mephitis were the primary nest predators, accounting for 56.7% of all video recorded nest depredations. Nests in our high intensity gas and oil area were 1.95 times more likely to succeed compared to our minimal intensity area. Camera monitored nests were 2.03 times more likely to succeed than non-camera monitored nests. Occupancy of mammalian nest predators was 6.9 times more likely in our study area of minimal gas and oil intensity compared to the high intensity area. Although only a correlative study, our results suggest energy development may alter the predator community, thereby increasing nest success for sharp-tailed grouse in areas of intense development, while adjacent areas may have increased predator occurrence and reduced nest success. Our study illustrates the potential influences of energy development on the nest predator-prey dynamics of sharp-tailed grouse in western North Dakota and the complexity of evaluating such impacts on wildlife.

Characterising of solid state electrochemical cells under operation

DEFF Research Database (Denmark)

Holtappels, Peter

2014-01-01

Compared to significant progress in PEMFC especially regarding the utilization of complex fuels such as methanol significant progress has been made by applying spectroscopic / differential IR and spectrometric techniques to working fuel cells, the processes in solid state high temperature...... electrochemical cells are still a "black box". In order to identify local reaction sites, surface coverage and potential/current introduced materials and surface modifications, in situ techniques are needed to gain a better understanding of the elementary and performance limiting steps for these cells...

Performance Evaluation of Solid Oxide Fuel Cell by Computer ...

African Journals Online (AJOL)

The search for sustainable energy source that can compete with the existing one led to the discovery and acceptance of fuel cell technologies as a perfect replacement for fossil fuel. The ability of Solid Oxide Fuel Cells (SOFC) to capture the heat generation during the process of energy generation from electrochemical ...

A mathematical model of the solid-polymer-electrolyte fuel cell

International Nuclear Information System (INIS)

Bernardi, D.M.; Verbrugge, M.W.

1992-01-01

This paper presents a mathematical model of the solid-polymer-electrolyte fuel cell and apply it to (i) investigate factors that limit cell performance and (ii) elucidate the mechanism of species transport in the complex network of gas, liquid, and solid phases of the cell. Calculations of cell polarization behavior compare favorably with existing experimental data. For most practical electrode thicknesses, model results indicate that the volume fraction of the cathode available for gas transport must exceed 20% in order to avoid unacceptably low cell-limiting current densities. It is shown that membrane dehydration can also pose limitations on operating current density; circumvention of this problem by appropriate membrane and electrode design and efficient water-management schemes is discussed. The authors' model results indicate that for a broad range of practical current densities there are no external water requirements because the water produced at the cathode is enough to satisfy the water requirement of the membrane

Jet Fuel Based High Pressure Solid Oxide Fuel Cell System

Science.gov (United States)

Gummalla, Mallika (Inventor); Yamanis, Jean (Inventor); Olsommer, Benoit (Inventor); Dardas, Zissis (Inventor); Bayt, Robert (Inventor); Srinivasan, Hari (Inventor); Dasgupta, Arindam (Inventor); Hardin, Larry (Inventor)

2015-01-01

A power system for an aircraft includes a solid oxide fuel cell system which generates electric power for the aircraft and an exhaust stream; and a heat exchanger for transferring heat from the exhaust stream of the solid oxide fuel cell to a heat requiring system or component of the aircraft. The heat can be transferred to fuel for the primary engine of the aircraft. Further, the same fuel can be used to power both the primary engine and the SOFC. A heat exchanger is positioned to cool reformate before feeding to the fuel cell. SOFC exhaust is treated and used as inerting gas. Finally, oxidant to the SOFC can be obtained from the aircraft cabin, or exterior, or both.

Hawaii ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seabird nesting colonies in coastal Hawaii. Vector points in this data set represent locations of...

Maryland ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for raptors in Maryland. Vector points in this data set represent bird nesting sites. Species-specific...

Fabrication and characterization of solid oxide cells for energy conversion and storage

Science.gov (United States)

Yang, Chenghao

2011-12-01

There has been an increasing interest in clean and renewable energy generation for highlighted energy and environmental concerns. Solid oxide cells (SOCs) have been considered as one of the promising technologies, since they can be operated efficiently both in electrolysis mode by generating hydrogen through steam electrolysis and fuel cell mode by electrochemically combining fuel with oxidant. The present work is devoted to performing a fundamental study of SOC in both fuel cell mode for power generation and electrolysis mode for fuel production. The research work on SOCs that can be operated reversibly for power generation and fuel production has been conducted in the following six projects: (1) High performance solid oxide electrolysis cell (SOEC) Fabrication of novel structured SOEC oxygen electrode with the conventional and commercial solid oxide fuel cell materials by screen-printing and infiltration fabrication methods. The microstructure, electrochemical properties and durability of SOECs has been investigated. It was found that the LSM infiltrated cell has an area specific resistance (ASR) of 0.20 Ω cm2 at 900°C at open circuit voltage with 50% absolute humidity (AH), which is relatively lower than that of the cell with LSM-YSZ oxygen electrode made by a conventional mixing method. Electrolysis cell with LSM infiltrated oxygen electrode has demonstrated stable performance under electrolysis operation with 0.33 A/cm2 and 50 vol.% AH at 800°C. (2) Advanced performance high temperature micro-tubular solid oxide fuel cell (MT-SOFC) Phase-inversion, dip-coating, high temperature co-sintering process and impregnation method were used to fabricate micro-tubular solid oxide fuel cell. The micro-structure of the micro-tubular fuel cell will be investigated and the power output and thermal robustness has been evaluated. High performance and rapid start-up behavior have been achieved, indicates that the MT-SOFC developed in this work can be a promising technology

Solid oxide electrolysis cell for decomposition of tritiated water

International Nuclear Information System (INIS)

Konishi, S.; Katsuta, H.; Naruse, Y.; Ohno, H.; Yoshida, H.

1984-01-01

The decomposition of tritiated water vapor with solid oxide electrolysis cell was proposed for the application to the D-T fusion reactor system. This method is essentially free from problems such as large tritium inventory, radiation damage, and generation of solid waste, so it is expected to be a promising one. Electrolysis of water vapor in argon carrier was performed using tube-type stabilized zirconia cell with porous platinum electrodes in the temperature range of 500 0 C to 950 0 C. High conversion ratio from water to hydrogen up to 99.9% was achieved. The characteristics of the cell is deduced from the Nernst's equation and conversion ratio is described as the function of the open circuit voltage. Experimental results agreed with the equation. Isotope effect in electrolysis is also discussed and experiments with heavy water were carried out. Obtained separation factor was slightly higher than the theoretical value

Biomechanical testing of materials in avian nests provides insight into nest construction behaviour

OpenAIRE

Biddle, Lucia E.; Deeming, D. Charles; Goodman, Adrian M.

2015-01-01

Animals that use materials to build nest structures have long since fascinated biologists and engineers alike. Avian nests are generally composed of collected materials brought together into a cup-like structure in which the bird sits to incubate eggs and, in many cases, it is where chicks are reared. Hence, the materials in a nest can be presumed to be loaded in compression, but relatively few studies have investigated the mechanical role of the nest elements and their position w...

Louisiana ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seabird and wading bird nesting colonies in coastal Louisiana. Vector points in this data set represent...

Nesting biology and life cycle of Nomia (Acunomia chalybeata Smith on Iriomote Island, southernmost Archipelago of Japan, with notes on the simultaneous occurrence of diapausing and non-diapausing prepupae within the same nests (Hymenoptera: Halictidae

Directory of Open Access Journals (Sweden)

Md. Abdul Hannan

2013-06-01

Full Text Available Nesting biology of the nomiine bee, Nomia (Acunomia chalybeata Smith, was studied in Iriomote Island, Japan (N24°15–25′ in 2003 and 2004. Its nesting period extended for 6 months from around the end of April to October. The nest aggregation was found in clay soil under shady conditions. Twenty nests/m2 were present at the highest density spot. Brood numbers in solitary nests were 5–20 (mean ± SD: 11.8 ± 4.7, n = 14, and in communal nests 12–101 (43.0 ± 41.0, n = 3. Each brood cluster in communal nests contained 0–32 brood cells (10.1 ± 8.0, n = 13, suggesting that each cohabitant provisioned independently own brood cells. At least 2 and partially 3 generations were estimated to occur in the year; however each nest produced simultaneously non-diapausing and diapausing prepupae. The percent rate of diapausing prepupae differed seasonally, and was 20.0–37.5% (30.3 ± 7.5%, n = 3 in overwintered generation and 0–100% (50.0 ± 39.8%, n = 9 in first generation, suggesting that the rate of production of dormant prepupae increased toward the later activity season. Production of the diapausing prepupae may function potentially to inhabit widely throughout different climatic zones. Female ratio (females/females + males in overwintered generation was 0.347 (50/144. Nest architecture, occurrence of communal nests and breaking of prepupal diapause are also mentioned.

Chimeric Antigen Receptors T Cell Therapy in Solid Tumor: Challenges and Clinical Applications

Directory of Open Access Journals (Sweden)

Hamid R. Mirzaei

2017-12-01

Full Text Available Adoptive cellular immunotherapy (ACT employing engineered T lymphocytes expressing chimeric antigen receptors (CARs has demonstrated promising antitumor effects in advanced hematologic cancers, such as relapsed or refractory acute lymphoblastic leukemia, chronic lymphocytic leukemia, and non-Hodgkin lymphoma, supporting the translation of ACT to non-hematological malignancies. Although CAR T cell therapy has made remarkable strides in the treatment of patients with certain hematological cancers, in solid tumors success has been limited likely due to heterogeneous antigen expression, immunosuppressive networks in the tumor microenvironment limiting CAR T cell function and persistence, and suboptimal trafficking to solid tumors. Here, we outline specific approaches to overcome barriers to CAR T cell effectiveness in the context of the tumor microenvironment and offer our perspective on how expanding the use of CAR T cells in solid tumors may require modifications in CAR T cell design. We anticipate these modifications will further expand CAR T cell therapy in clinical practice.

Turnover rate of hypoxic cells in solid tumors

International Nuclear Information System (INIS)

Ljungkvist, A.S.E.; Bussink, J.; Rijken, P.F.J.W.; Van Der Kogel, A.J.

2003-01-01

Most solid tumors contain hypoxic cells, and both the amount and duration of tumor hypoxia has been shown to influence the effect of radiation treatment negatively. It is important to understand the dynamic processes within the hypoxic cell population in non-treated tumors, and the effect of different treatment modalities on the kinetics of hypoxic cells to be able to design optimal combined modality treatments. The turnover rate of hypoxic cells was analyzed in three different solid tumor models with a double bio-reductive hypoxic marker assay with sequential injection of the two hypoxic markers. Previously it was shown that this assay could be used to detect both a decrease and an increase of tumor hypoxia in relation to the tumor vasculature with high spatial resolution. In this study the first hypoxic marker, pimonidazole, was administered at variable times relative to tumor harvest, and the second hypoxic marker, CCI-103F, was injected at a fixed time before harvest. The hypoxic cell turnover rate was calculated as the loss of pimonidazole positive cells relative to CCI-103F. The murine C38 line had the fastest hypoxic turnover rate of 60% /24h and the human xenograft line SCCNij3 had the slowest hypoxic turnover rate of 30% /24 h. The hypoxic turnover rate was most heterogeneous in the SCCNij3 line that even contained viable groups of cells that had been hypoxic for at least 5 days. The human xenograft line MEC82 fell in between with a hypoxic turnover rate of 50% /24 h. The hypoxic cell turnover was related to the potential tumor volume doubling time (Tpot) with a Tpot of 26h in C38 and 103h in SCCNij3. The dynamics of hypoxic cells, quantified with a double hypoxic marker method, showed large differences in hypoxic cell turnover rate and were related to Tpot

Raptor nest management on power lines

Energy Technology Data Exchange (ETDEWEB)

Harness, R.E. [EDM International Inc., Fort Collins, CO (United States)

2005-07-01

Many utilities in South Africa are now implementing labor-intensive methods to combat raptor nesting on power transmission lines. Methods have typically included direct nest removal and trimming of nest materials. However, the process is often unsuccessful, and utilities are now learning to accommodate the raptor nests. This paper argued that managing nests on utility structures has solved many operational problems and has resulted in positive publicity for many line operators. Nest management options included the use of stick deflectors to prevent nest material from accumulating during initial nest construction, as well as encouraging raptors to shift their efforts to a more suitable location. Raptors will often accept alternative nesting platforms, and taller, surrogate nesting poles can be placed next to distribution line structures. Elevated platforms can also be placed on problematic distribution structures, but may result in birds coming into contact with unprotected equipment. It was concluded that a successful nest management program includes plans to make nearby lines safe for raptors and to prevent their electrocution. Providing nests with bird-friendly utility configurations can result in electric facilities enhancing wild raptor populations without impacting power reliability. 14 refs., 9 figs.

An initial applications study of ceria-gadolinia solid oxide fuel cells: V. 1

Energy Technology Data Exchange (ETDEWEB)

Bauen, A.; Hart, D.; Mould, B.

1998-11-01

Fuel cells are categorised by their electrolytes, and the solid oxide fuel cell is so called because its electrolyte consists of a solid ceramic oxide. Commonly this has been a form of zirconia, though other materials are now being considered for their different electrical properties. One of these, ceria doped with gadolinia, shows promise for use in lower temperature regimes than zirconia, and may open up different areas of a future market for consideration. This report considers the opportunities for ceria-gadolinia solid oxide fuel cell systems by comparing them with the application requirements in markets where fuel cells may have potential. The advantages and disadvantages of the technology are analysed, together with the state of the art in research and development. The direction in which research effort needs to move to address some of the issues is assessed. The report then draws conclusions regarding the potential of ceria-gadolinia in solid oxide fuel cell systems and in the energy markets as a whole. It should be noted that while this report is an applications study, some technology assessment has been included. Much of this is found in Volume 2. (author)

Nest-site selection and nest success of an Arctic-breeding passerine, Smith's Longspur, in a changing climate

Science.gov (United States)

McFarland, Heather R.; Kendall, Steve J.; Powell, Abby

2017-01-01

Despite changes in shrub cover and weather patterns associated with climate change in the Arctic, little is known about the breeding requirements of most passerines tied to northern regions. We investigated the nesting biology and nest habitat characteristics of Smith's Longspurs (Calcarius pictus) in 2 study areas in the Brooks Range of Alaska, USA. First, we examined variation in nesting phenology in relation to local temperatures. We then characterized nesting habitat and analyzed nest-site selection for a subset of nests (n = 86) in comparison with paired random points. Finally, we estimated the daily survival rate of 257 nests found in 2007–2013 with respect to both habitat characteristics and weather variables. Nest initiation was delayed in years with snow events, heavy rain, and freezing temperatures early in the breeding season. Nests were typically found in open, low-shrub tundra, and never among tall shrubs (mean shrub height at nests = 26.8 ± 6.7 cm). We observed weak nest-site selection patterns. Considering the similarity between nest sites and paired random points, coupled with the unique social mating system of Smith's Longspurs, we suggest that habitat selection may occur at the neighborhood scale and not at the nest-site scale. The best approximating model explaining nest survival suggested a positive relationship with the numbers of days above 21°C that an individual nest experienced; there was little support for models containing habitat variables. The daily nest survival rate was high (0.972–0.982) compared with that of most passerines in forested or grassland habitats, but similar to that of passerines nesting on tundra. Considering their high nesting success and ability to delay nest initiation during inclement weather, Smith's Longspurs may be resilient to predicted changes in weather regimes on the breeding grounds. Thus, the greatest threat to breeding Smith's Longspurs associated with climate change may be the loss of low

Nesting Activity of Loggerhead Turtles (Caretta caretta at Göksu Delta, Turkey during 2004 and 2008 nesting seasons

Directory of Open Access Journals (Sweden)

Salih H. Durmus

2011-07-01

Full Text Available Göksu Delta is one of the most important nesting beaches in Turkey for the endangered loggerhead turtle (Caretta caretta. This paper provides information on the nesting activities of loggerhead turtles, the spatial and temporal distribution of nesting, nesting success, nesting density, hatching success, incubation duration and clutch size over two nesting seasons. A total of 902 emergences occurred over two seasons, of which 239 (26.5% nests were deposited (137 nests in 2004 and 102 nests in 2008 and the overall mean nesting density was 3.4 nests/km. The peak of nesting emergences takes place mainly in June. Of the overall nests, 226 (94.6% were excavated and 16044 eggs were counted. Of these eggs, 3680 (22.9% hatchlings emerged and 2695 (73.2% of hatchlings of them were able to reach the sea. The mean number of eggs per clutch was 71 (range: 15 – 143. The shortest and longest incubation duration in these 2 seasons ranged from 46 to 62 days with a mean of 53 days. The main problems are negatively affecting loggerhead turtle population at Göksu Delta are dense jackal predation both adult and eggs and inundation in nests. The average nesting effort here (mean: 119.5 nests/season confirms that Göksu Delta is one of the most important nesting sites for loggerhead turtles in Turkey.

Nesting biology of four species of Trypoxylon (Trypargilum (Hymenoptera: Crabronidae in Chaco Serrano woodland, Central Argentina

Directory of Open Access Journals (Sweden)

Mariana L Musicante

2010-12-01

Full Text Available Trypoxylon (Trypargilum (Crabronidae wasps are solitary spider predators that can build their nests in artificial trap-nests, which enables study of their nesting architecture and biology. Twenty traps (each containing 15-30 internodes of cane were placed in each of nine sites of Chaco Serrano Woodland in Central Argentina (Córdoba in October 2005, and were recovered in June 2006. We obtained 91 nests of four species of Trypoxylon (Trypargilum. In the laboratory, each Trypoxylon nest was sectioned longitudinally to study its architecture. The number of brood cells was counted, and the occurrence and length of vestibular and intercalary cells and the pre-closing plug space were recorded. We measured the diameter of the cane entrance, total length of the nest, length of each brood cell, maximum thickness of mud partitions and closing plug thickness. We also recorded the cell contents: the wasps, their natural enemies and the prey spiders. Mortality was assessed and the sex ratio calculated for each species. Finally, the nests were examined to help clarify the function of the vestibular cell. The nest architecture was similar in the four species, with linear brood cells located one after the other separated by mud partitions, as in other species of the subgenus Trypargilum. Forty-eight percent of the nests had vestibular cells, but only two had intercalary cells. The thickness of the mud partitions and the length of the brood cells differed among species and were related to the size of the emerged wasp. The diameter of the nest entrance was directly related to the average length of the fore-tibia. Sex ratios of all species did not deviate from 0.5. Mortality due to parasitoids (Eulophidae; Melittobia sp. was similar among species, while the mortality due to cuckoo wasps (Chrysididae in T. lactitarse was higher than in the other species. The presence of vestibular cells was not related either to the mortality due to natural enemies or to the

A new technique in the excavation of ground-nest bee burrows (Hymenoptera: Apoidea

Directory of Open Access Journals (Sweden)

Diego Marinho

2018-01-01

Full Text Available Bees have a diversified natural history, thus the methods applied to study such diversity are varied. When it comes to studies of nesting biology, bees which nest in pre-existing cavities have been reasonably well studied since researchers started using trap-nests. However, bees whose nests are built underground are poorly studied due to the difficulty of finding natural nesting areas and the absence of a method that facilitates bee nest excavation. The latter is evidenced by the lack of accurate descriptions in literature of how nests are excavated. In this study we tested cylindrical rubber refills of eraser pen as a new material to be used as a tracer of underground nest galleries in a natural nesting area of two species of Epicharis Klug, 1807 (Apidae. We compared this technique directly with plaster in powder form mixed with water and our results with other methodological studies describing alternative methods and materials. The rubber refill technique overcame the main issues presented by materials such as plaster, molten metal alloys and bioplastic, namely: death of the organisms by high temperatures and/or formation of plugs and materials unduly following the roots inside the galleries. Keywords: Apidae, Apoidea, Brood cells, Methodology, Solitary bees

Characterization of cell suspensions from solid tumors

International Nuclear Information System (INIS)

Pallavicini, M.

1985-01-01

The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with different degrees of clonogenicity, as well as altered biochemical features, such as loss of cellular proteins, surface antigens, nucleotide pools, etc. The quality of the cell suspension can be judged by the degree of cell clumping and level of cellular debris, both of which impact on flow cytometric measurements and studies in which the number of cells be known accurately. Finally, if the data measured on the cells in suspension are to be extrapolated to phenomena occurring in the tumor in situ, it is desirable that the cells in suspension are representative of those in the solid tumor in vivo. This report compares characteristics of tumor cell suspensions obtained by different types of selected disaggregation methods. 33 refs., 2 figs., 4 tabs

CHALLENGES IN GENERATING HYDROGEN BY HIGH TEMPERATURE ELECTROLYSIS USING SOLID OXIDE CELLS

Energy Technology Data Exchange (ETDEWEB)

M. S. Sohal; J. E. O' Brien; C. M. Stoots; M. G. McKellar; J. S. Herring; E. A. Harvego

2008-03-01

Idaho National Laboratory’s (INL) high temperature electrolysis research to generate hydrogen using solid oxide electrolysis cells is presented in this paper. The research results reported here have been obtained in a laboratory-scale apparatus. These results and common scale-up issues also indicate that for the technology to be successful in a large industrial setting, several technical, economical, and manufacturing issues have to be resolved. Some of the issues related to solid oxide cells are stack design and performance optimization, identification and evaluation of cell performance degradation parameters and processes, integrity and reliability of the solid oxide electrolysis (SOEC) stacks, life-time prediction and extension of the SOEC stack, and cost reduction and economic manufacturing of the SOEC stacks. Besides the solid oxide cells, balance of the hydrogen generating plant also needs significant development. These issues are process and ohmic heat source needed for maintaining the reaction temperature (~830°C), high temperature heat exchangers and recuperators, equal distribution of the reactants into each cell, system analysis of hydrogen and associated energy generating plant, and cost optimization. An economic analysis of this plant was performed using the standardized H2A Analysis Methodology developed by the Department of Energy (DOE) Hydrogen Program, and using realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.23/kg of hydrogen assuming an internal rate of return of 10%. These issues need interdisciplinary research effort of federal laboratories, solid oxide cell manufacturers, hydrogen consumers, and other such stakeholders. This paper discusses research and development accomplished by INL on such issues and highlights associated challenges that need to

Quality Assurance of Solid Oxide Fuel Cell (SOFC) and Electrolyser (SOEC) Stacks

DEFF Research Database (Denmark)

Lang, Michael; Auer, Corinna; Couturier, Karine

2017-01-01

In the EU-funded project “Solid oxide cell and stack testing and quality assurance” (SOCTESQA) standardized and industry wide test modules and programs for high temperature solid oxide cells and stacks are being developed. These test procedures can be applied for the fuel cell (SOFC......), the electrolysis (SOEC) and in the combined SOFC/SOEC mode. In order to optimize the test modules the project partners have tested identical SOC stacks with the same test programs in several testing campaigns. Altogether 10 pre-normative test modules were developed: Start-up, current-voltage characteristics...

Buteo Nesting Ecology: Evaluating Nesting of Swainson’s Hawks in the Northern Great Plains

Science.gov (United States)

Inselman, Will M.; Datta, Shubham; Jenks, Jonathan A.; Jensen, Kent C.; Grovenburg, Troy W.

2015-01-01

Swainson’s hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson’s hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson’s hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, S Dist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%–42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson’s hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson’s hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson’s hawks arriving to the breeding grounds. PMID:26327440

AlliedSignal solid oxide fuel cell technology

Energy Technology Data Exchange (ETDEWEB)

Minh, N.; Barr, K.; Kelly, P.; Montgomery, K. [AlliedSignal Aerospace Equipment Systems, Torrance, CA (United States)

1996-12-31

AlliedSignal has been developing high-performance, lightweight solid oxide fuel cell (SOFC) technology for a broad spectrum of electric power generation applications. This technology is well suited for use in a variety of power systems, ranging from commercial cogeneration to military mobile power sources. The AlliedSignal SOFC is based on stacking high-performance thin-electrolyte cells with lightweight metallic interconnect assemblies to form a compact structure. The fuel cell can be operated at reduced temperatures (600{degrees} to 800{degrees}C). SOFC stacks based on this design has the potential of producing 1 kW/kg and 1 ML. This paper summarizes the technical status of the design, manufacture, and operation of AlliedSignal SOFCs.

Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

Energy Technology Data Exchange (ETDEWEB)

Faress Rahman; Nguyen Minh

2004-01-04

This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) during the July 2003 to December 2003 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a micro-turbine. In addition, an activity included in this program focuses on the development of an integrated coal gasification fuel cell system concept based on planar SOFC technology. Also, another activity included in this program focuses on the development of SOFC scale up strategies.

"Fibrous nests" in human hepatocellular carcinoma express a Wnt-induced gene signature associated with poor clinical outcome.

Science.gov (United States)

Désert, Romain; Mebarki, Sihem; Desille, Mireille; Sicard, Marie; Lavergne, Elise; Renaud, Stéphanie; Bergeat, Damien; Sulpice, Laurent; Perret, Christine; Turlin, Bruno; Clément, Bruno; Musso, Orlando

2016-12-01

Hepatocellular carcinoma (HCC) is the 3rd cause of cancer-related death worldwide. Most cases arise in a background of chronic inflammation, extracellular matrix (ECM) remodeling, severe fibrosis and stem/progenitor cell amplification. Although HCCs are soft cellular tumors, they may contain fibrous nests within the tumor mass. Thus, the aim of this study was to explore cancer cell phenotypes in fibrous nests. Combined anatomic pathology, tissue microarray and real-time PCR analyses revealed that HCCs (n=82) containing fibrous nests were poorly differentiated, expressed Wnt pathway components and target genes, as well as markers of stem/progenitor cells, such as CD44, LGR5 and SOX9. Consistently, in severe liver fibroses (n=66) and in HCCs containing fibrous nests, weighted correlation analysis revealed a gene network including the myofibroblast marker ACTA2, the basement membrane components COL4A1 and LAMC1, the Wnt pathway members FZD1; FZD7; WNT2; LEF1; DKK1 and the Secreted Frizzled Related Proteins (SFRPs) 1; 2 and 5. Moreover, unbiased random survival forest analysis of a transcriptomic dataset of 247 HCC patients revealed high DKK1, COL4A1, SFRP1 and LAMC1 to be associated with advanced tumor staging as well as with bad overall and disease-free survival. In vitro, these genes were upregulated in liver cancer stem/progenitor cells upon Wnt-induced mesenchymal commitment and myofibroblast differentiation. In conclusion, fibrous nests express Wnt target genes, as well as markers of cancer stem cells and mesenchymal commitment. Fibrous nests embody the specific microenvironment of the cancer stem cell niche and can be detected by routine anatomic pathology analyses. Copyright © 2016 Elsevier Ltd. All rights reserved.

Solid oxide electrolysis cell for decomposition of tritiated water

International Nuclear Information System (INIS)

Konishi, S.; Ohno, H.; Yoshida, H.; Katsuta, H.; Naruse, Y.

1986-01-01

The decomposition of tritiated water vapor by means of solid oxide electrolysis cells has been proposed for the application to the D-T fusion reactor system. This method is essentially free from problems such as large tritium inventory, radiation damage, and generation of solid waste, so it is expected to be a promising one. Electrolysis of water vapor in an argon carrier was performed using a tube-type stabilized zirconia cell with porous platinum electrodes over the temperature range 500-950 0 C. High conversion ratios from water to hydrogen, of up to 99.9%, were achieved. The characteristics of the cell were deduced from the Nernst equation and the conversion ratios expressed as a function of the IR-free voltage. Experimental results agreed with the equation. The isotope effect in electrolysis is also discussed and experiments with heavy water were carried out. The obtained separation factor was slightly higher than the theoretical value. (author)

Hydrogen production through high-temperature electrolysis in a solid oxide cell

International Nuclear Information System (INIS)

Herring, J.St.; Lessing, P.; O'Brien, J.E.; Stoots, C.; Hartvigsen, J.; Elangovan, S.

2004-01-01

An experimental research programme is being conducted by the INEEL and Ceramatec, Inc., to test the high-temperature, electrolytic production of hydrogen from steam using a solid oxide cell. The research team is designing and testing solid oxide cells for operation in the electrolysis mode, producing hydrogen rising a high-temperature heat and electrical energy. The high-temperature heat and the electrical power would be supplied simultaneously by a high-temperature nuclear reactor. Operation at high temperature reduces the electrical energy requirement for electrolysis and also increases the thermal efficiency of the power-generating cycle. The high-temperature electrolysis process will utilize heat from a specialized secondary loop carrying a steam/hydrogen mixture. It is expected that, through the combination of a high-temperature reactor and high-temperature electrolysis, the process will achieve an overall thermal conversion efficiency of 40 to 50%o while avoiding the challenging chemistry and corrosion issues associated with the thermochemical processes. Planar solid oxide cell technology is being utilised because it has the best potential for high efficiency due to minimized voltage and current losses. These losses also decrease with increasing temperature. Initial testing has determined the performance of single 'button' cells. Subsequent testing will investigate the performance of multiple-cell stacks operating in the electrolysis mode. Testing is being performed both at Ceramatec and at INEEL. The first cells to be tested were single cells based on existing materials and fabrication technology developed at Ceramatec for production of solid oxide fuel cells. These cells use a relatively thick (∼ 175 μm) electrolyte of yttria- or scandia-stabilised zirconia, with nickel-zirconia cermet anodes and strontium-doped lanthanum manganite cathodes. Additional custom cells with lanthanum gallate electrolyte have been developed and tested. Results to date have

Unusual raptor nests around the world

Science.gov (United States)

Ellis, D.H.; Craig, T.; Craig, E.; Postupalsky, S.; LaRue, C.T.; Nelson, R.W.; Anderson, D.W.; Henny, C.J.; Watson, J.; Millsap, B.A.; Dawson, J.W.; Cole, K.L.; Martin, E.M.; Margalida, A.; Kung, P.

2009-01-01

From surveys in many countries, we report raptors using unusual nesting materials (e.g., paper money, rags, metal, antlers, and large bones) and unusual nesting situations. For example, we documented nests of Steppe Eagles Aquila nipalensis and Upland Buzzards Buteo hemilasius on the ground beside well-traveled roads, Saker Falcon Falco cherrug eyries in attics and a cistern, and Osprey Pandion haliaetus nests on the masts of boats and on a suspended automobile. Other records include a Golden Eagle A. chrysaetos nest 7.0 m in height, believed to be the tallest nest ever described, and, for the same species, we report nesting in rudimentary nests. Some nest sites are within a few meters of known predators or competitors. These unusual observations may be important in revealing the plasticity of a species' behavioral repertoire. ?? 2009 The Raptor Research Foundation, Inc.

Sexually selected nest-building--Pomatoschistus minutus males build smaller nest-openings in the presence of sneaker males.

Science.gov (United States)

Svensson, O; Kvarnemo, C

2003-09-01

Both natural selection and sexual selection may act on nest-building. We tested experimentally how different regimes of egg-predation and male-male competition influence nest-building before mating, using the marine fish sand goby, Pomatoschistus minutus. Males with sneaker males present built the smallest nest-openings, smaller than males held alone or with Pomatoschistus microps males (which may predate eggs and compete over nest-sites but not compete over fertilizations). Males with visual access to other nest-building males tended also to build smaller openings than males held alone or with P. microps. Males with egg-predators present built nests with openings not differing significantly from any other treatment. Our results indicate that the small nest-openings found in the sneaker male treatment are sexually selected through protection against sneaking or by female choice. Across treatments, time span before a male started to build his nest also explained variation in nest-opening width; males starting late built larger nest-openings.

Development with age of nest box use and gregarious nesting in laying hens

DEFF Research Database (Denmark)

Riber, Anja Brinch

2010-01-01

in position (left + corner, middle, and right). Nesting behaviour was video recorded for 5 days in each of five distinct periods: age 20, 26, 32, 38, and 44 weeks. The total number of visits and the number of gregarious visits were higher in the left nest box than in the other two nest boxes at all ages...

Predation on simulated duck nests in relation to nest density and landscape structure

Czech Academy of Sciences Publication Activity Database

Padyšáková, E.; Šálek, Martin; Poledník, L.; Sedláček, František; Albrecht, Tomáš

2010-01-01

Roč. 37, č. 7 (2010), s. 597-603 ISSN 1035-3712 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z60930519 Keywords : density-dependent predation * littoral patch * landscape type * nest predators * nest success * simulated nests Subject RIV: EG - Zoology Impact factor: 1.205, year: 2010

SOLID OXIDE FUEL CELL HYBRID SYSTEM FOR DISTRIBUTED POWER GENERATION

Energy Technology Data Exchange (ETDEWEB)

Faress Rahman; Nguyen Minh

2003-07-01

This report summarizes the work performed by Hybrid Power Generation Systems, LLC during the January 2003 to June 2003 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a micro-turbine. In addition, an activity included in this program focuses on the development of an integrated coal gasification fuel cell system concept based on planar SOFC technology. This report summarizes the results obtained to date on: System performance analysis and model optimization; Reliability and cost model development; System control including dynamic model development; Heat exchanger material tests and life analysis; Pressurized SOFC evaluation; and Pre-baseline system definition for coal gasification fuel cell system concept.

Discovery of a new Kittlitz's murrelet nest: Clues to habitat selection and nest-site fidelity

Science.gov (United States)

Piatt, John F.; Naslund, Nancy L.; van Pelt, Thomas I.

1999-01-01

On 13 June 1993, a new Kittlitz's murrelet (Brachyramphus brevirostris) nest was discovered near Red Mountain on the Kenai Peninsula, Alaska. The nest was on a 22° slope at about 900 m elevation with a northeast aspect, and contained a 60.2 × 40.6 mm egg that weighed 49.0 g. Downy feathers and weathered fecal material found at the nest indicated re-use from a previous year, suggesting possible nest site fidelity. The nest was located in an area scoured by winds and free of snow during early spring, suggesting that this may be an important mesoscale factor influencing selection of nesting habitat. Proximity to suitable foraging habitat, particularly sheltered bays and glacial river outflows, may affect breeding habitat choice over larger spatial scales.

Pressurized Operation of a Planar Solid Oxide Cell Stack

DEFF Research Database (Denmark)

Jensen, Søren Højgaard; Sun, Xiufu; Ebbesen, Sune Dalgaard

2016-01-01

, pressurized SOEC based electrolyzers can become more efficient both energy- and cost-wise than PEM and Alkaline systems. Pressurization of SOFCs can significantly increase the cell power density and reduce the size of auxiliary components. In the present study, a SOC stack was successfully operated......Solid oxide cells (SOCs) can be operated either as fuel cells (SOFC) to convert fuels to electricity or as electrolyzers (SOEC) to convert electricity to fuels such as hydrogen or methane. Pressurized operation of SOCs provide several benefits on both cell and system level. If successfully matured...

Nest-site selection by cavity-nesting birds in relation to postfire salvage logging

Science.gov (United States)

Victoria A. Saab; Robin E. Russell; Jonathan G. Dudley

2009-01-01

Large wildfire events in coniferous forests of the western United States are often followed by postfire timber harvest. The long-term impacts of postfire timber harvest on fire-associated cavity-nesting bird species are not well documented. We studied nest-site selection by cavity-nesting birds over a 10-year period (1994-2003), representing 1-11 years after fire, on...

Artificial covering on trap nests improves the colonization of trap-nesting wasps

OpenAIRE

Taki, Hisatomo; Kevan, Peter G.; Viana, Blandina Felipe; Silva, Fabiana O.; Buck, Matthias

2008-01-01

Acesso restrito: Texto completo. p. 225-229 To evaluate the role that a trap-nest cover might have on sampling methodologies, the abundance of each species of trap-nesting Hymenoptera and the parasitism rate in a Canadian forest were compared between artificially covered and uncovered traps. Of trap tubes exposed at eight forest sites in six trap-nest boxes, 531 trap tubes were occupied and 1216 individuals of 12 wasp species of four predatory families, Vespidae (Eumeninae), Crabronidae...

Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird

OpenAIRE

Hollander, Franck A.; Van Dyck, Hans; San Martin, Gilles; Titeux, Nicolas

2015-01-01

In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius ...

Interaction in Balanced Cross Nested Designs

Science.gov (United States)

Ramos, Paulo; Mexia, João T.; Carvalho, Francisco; Covas, Ricardo

2011-09-01

Commutative Jordan Algebras, CJA, are used in the study of mixed models obtained, through crossing and nesting, from simpler ones. In the study of cross nested models the interaction between nested factors have been systematically discarded. However this can constitutes an artificial simplification of the models. We point out that, when two crossed factors interact, such interaction is symmetric, both factors playing in it equivalent roles, while when two nested factors interact, the interaction is determined by the nesting factor. These interactions will be called interactions with nesting. In this work we present a coherent formulation of the algebraic structure of models enabling the choice of families of interactions between cross and nested factors using binary operations on CJA.

Parental investment decisions in response to ambient nest-predation risk versus actual predation on the prior nest

Science.gov (United States)

Chalfoun, A.D.; Martin, T.E.

2010-01-01

Theory predicts that parents should invest less in dependent offspring with lower reproductive value, such as those with a high risk of predation. Moreover, high predation risk can favor reduced parental activity when such activity attracts nest predators. Yet, the ability of parents to assess ambient nest-predation risk and respond adaptively remains unclear, especially where nest-predator assemblages are diverse and potentially difficult to assess. We tested whether variation in parental investment by a multi-brooded songbird (Brewer's Sparrow, Spizella breweri) in an environment (sagebrush steppe) with diverse predators was predicted by ambient nest-predation risk or direct experience with nest predation. Variation among eight sites in ambient nest-predation risk, assayed by daily probabilities of nest predation, was largely uncorrelated across four years. In this system risk may therefore be unpredictable, and aspects of parental investment (clutch size, egg mass, incubation rhythms, nestling-feeding rates) were not related to ambient risk. Moreover, investment at first nests that were successful did not differ from that at nests that were depredated, suggesting parents could not assess and respond to territorylevel nest-predation risk. However, parents whose nests were depredated reduced clutch sizes and activity at nests attempted later in the season by increasing the length of incubation shifts (on-bouts) and recesses (off-bouts) and decreasing trips to feed nestlings. In this unpredictable environment parent birds may therefore lack sufficient cues of ambient risk on which to base their investment decisions and instead rely on direct experience with nest predation to inform at least some of their decisions. ?? 2010 The Cooper Ornithological Society.

Landscape forest cover and edge effects on songbird nest predation vary by nest predator

Science.gov (United States)

W. Andrew Cox; Frank R. III Thompson; John. Faaborg

2012-01-01

Rates of nest predation for birds vary between and within species across multiple spatial scales, but we have a poor understanding of which predators drive such patterns. We video-monitored nests and identified predators at 120 nests of the Acadian Flycatcher (Empidonax virescens) and the Indigo Bunting (Passerina cyanea) at eight...

Nest Material Shapes Eggs Bacterial Environment.

Directory of Open Access Journals (Sweden)

Cristina Ruiz-Castellano

Full Text Available Selective pressures imposed by pathogenic microorganisms to embryos have selected in hosts for a battery of antimicrobial lines of defenses that includes physical and chemical barriers. Due to the antimicrobial properties of volatile compounds of green plants and of chemicals of feather degrading bacteria, the use of aromatic plants and feathers for nest building has been suggested as one of these barriers. However, experimental evidence suggesting such effects is scarce in the literature. During two consecutive years, we explored experimentally the effects of these nest materials on loads of different groups of bacteria (mesophilic bacteria, Enterobacteriaceae, Staphylococcus and Enterococcus of eggshells in nests of spotless starlings (Sturnus unicolor at the beginning and at the end of the incubation period. This was also explored in artificial nests without incubation activity. We also experimentally increased bacterial density of eggs in natural and artificial nests and explored the effects of nest lining treatments on eggshell bacterial load. Support for the hypothetical antimicrobial function of nest materials was mainly detected for the year and location with larger average values of eggshell bacterial density. The beneficial effects of feathers and plants were more easily detected in artificial nests with no incubation activity, suggesting an active role of incubation against bacterial colonization of eggshells. Pigmented and unpigmented feathers reduced eggshell bacterial load in starling nests and artificial nest boxes. Results from artificial nests allowed us to discuss and discard alternative scenarios explaining the detected association, particularly those related to the possible sexual role of feathers and aromatic plants in starling nests. All these results considered together confirm the antimicrobial functionality mainly of feathers but also of plants used as nest materials, and highlight the importance of temporally and

Nest Material Shapes Eggs Bacterial Environment.

Science.gov (United States)

Ruiz-Castellano, Cristina; Tomás, Gustavo; Ruiz-Rodríguez, Magdalena; Martín-Gálvez, David; Soler, Juan José

2016-01-01

Selective pressures imposed by pathogenic microorganisms to embryos have selected in hosts for a battery of antimicrobial lines of defenses that includes physical and chemical barriers. Due to the antimicrobial properties of volatile compounds of green plants and of chemicals of feather degrading bacteria, the use of aromatic plants and feathers for nest building has been suggested as one of these barriers. However, experimental evidence suggesting such effects is scarce in the literature. During two consecutive years, we explored experimentally the effects of these nest materials on loads of different groups of bacteria (mesophilic bacteria, Enterobacteriaceae, Staphylococcus and Enterococcus) of eggshells in nests of spotless starlings (Sturnus unicolor) at the beginning and at the end of the incubation period. This was also explored in artificial nests without incubation activity. We also experimentally increased bacterial density of eggs in natural and artificial nests and explored the effects of nest lining treatments on eggshell bacterial load. Support for the hypothetical antimicrobial function of nest materials was mainly detected for the year and location with larger average values of eggshell bacterial density. The beneficial effects of feathers and plants were more easily detected in artificial nests with no incubation activity, suggesting an active role of incubation against bacterial colonization of eggshells. Pigmented and unpigmented feathers reduced eggshell bacterial load in starling nests and artificial nest boxes. Results from artificial nests allowed us to discuss and discard alternative scenarios explaining the detected association, particularly those related to the possible sexual role of feathers and aromatic plants in starling nests. All these results considered together confirm the antimicrobial functionality mainly of feathers but also of plants used as nest materials, and highlight the importance of temporally and geographically

Design of nest access grids and perches in front of the nests: Influence on the behavior of laying hens.

Science.gov (United States)

Stämpfli, K; Buchwalder, T; Fröhlich, E K F; Roth, B A

2013-04-01

In aviary systems for laying hens, it is important to provide suitable nest access platforms in front of the nests, allowing hens to reach and explore each of the nests easily. This access platform is needed to achieve good nest acceptance by the hens and thereby prevent mislaid eggs. In the present experiment, the behavior of hens using 2 different nest access platforms, a plastic grid and 2 wooden perches, was examined. Furthermore, the nests were placed on both sides of the aviary rack (corridor side and outdoor side), either integrated into the aviary rack itself (integrated nest; IN) or placed on the walls of the pens (wall nest; WN), resulting in a 2 × 2 factorial design Four thousand five hundred white laying hens were housed in 20 test pens. The eggs in the nests and mislaid eggs were collected daily, and the behavior of hens on the nest accesses was filmed during wk 25 and 26, using focal observation and scan sampling methods. More balancing, body contact, and agonistic interactions were expected for nests with perches, whereas more walking and nest inspections were expected for nests with grids. There were more mislaid eggs and balancing found in pens equipped with nests with wooden perches. More agonistic interactions and balancing, less standing, and a longer duration of nest inspection were found with the WN compared with the IN. Interactions between platform design and position of the nests were found for duration of nest visits, body contact, and walking, with the highest amount for WN equipped with plastic grids. Nests on the corridor side were favored by the hens. Nest-related behaviors, such as nest inspection, standing, and walking, decreased over time as did the number of hens on the nest accesses, whereas sitting increased. These results indicate that the hens had more difficulties in gripping the perches as designed. The lower number of hens on the nest access platforms in front of IN may be due to a better distribution around nests and tier

Small-scale area effect on species richness and nesting occupancy of cavity-nesting bees and wasps

Directory of Open Access Journals (Sweden)

Rafael D. Loyola

2011-03-01

Full Text Available Small-scale area effect on species richness and nesting occupancy of cavity-nesting bees and wasps. The research was conducted in an urban forest remnant in southeast Brazil. We tested the predictions of the following hypotheses: (1 larger areas present higher species richness of bees and wasps, (2 solitary bees and wasps occupy more nests in larger areas, (3 rare species occupy more nests in smaller areas. We sampled Aculeate bees and wasps using trap nests from February to November 2004. We placed trap nests in sampling units (SU with different size (25, 100 and 400 m² located in 6 ha of secondary mesophytic forest. One hundred and thirty-seven trap nests were occupied by seven species of bees and four species of wasps. We found an increase in wasp, but not bee species richness following increase in SU size. Hymenoptera richness (i.e. bees plus wasps was also greater in larger SU. Both the number and density of occupied nests increased with SU size. The wasp Trypoxylon lactitarse responded significantly to area size, larger SU having more occupied nests. The same pattern was exhibited by the wasp Auplopus militaris, the Megachile bee species, and the bee Anthodioctes megachiloides. Only Trypoxylon sp. was not affected by SU size. Our results show that cavity-nesting bee and wasps respond differently to the area effects. Such findings must be complemented by information on the frequency and dynamics of area colonization and nest occupancy by species of solitary Hymenoptera.

Comparison of tumour age response to radiation for cells derived from tissue culture or solid tumours

International Nuclear Information System (INIS)

Keng, P.C.; Siemann, D.W.; Rochester Univ., NY; Rochester Univ., NY; Wheeler, K.T.

1984-01-01

Direct comparison of the cell age response of 9L and KHT tumour cells derived either from tissue culture or solid tumours was achieved. Cells from dissociated KHT and 9L tumours (the latter implanted either subcutaneously or intracerebrally) and cells from tissue culture were separated into homogenous sized populations by centrifugal elutriation. In both tumour models these homogeneous sized populations correspond to populations enriched at different stages of the cell cycle. The survival of these elutriated cell populations was measured after a single dose of Cs-137 gamma rays. For cells isolated from 9L solid tumours, there was little variation in radiosensitivity throughout the cell cycle; however, a very small but significant increase in resistance was found in late G 1 cells. This lack of a large variation in radiosensitivity through the cell cycle for 9L cells from solid tumours also was seen in 9L cells growing in monolayer tissue culture. When similar experiments were performed using the KHT sarcoma tumour model, the results showed that KHT cells in vitro exhibited a fairly conventional increase in radioresistance in both mid G 1 and late S. However, the cell age response of KHT cells from solid tumours was different; particularly in the late S and G 2 + M phases. (author)

Nested Potential Games

OpenAIRE

Hiroshi Uno

2007-01-01

This paper proposes a new class of potential games, the nested potential games, which generalize the potential games defined in Monderer and Shapley (1996), as well as the pseudo-potential games defined in Dubey et al. (2006). We show that each maximizer of a nested potential is a Nash equilibrium.

Nesting ecology and nest survival of lesser prairie-chickens on the Southern High Plains of Texas

Science.gov (United States)

Grisham, Blake A.; Borsdorf, Philip K.; Boal, Clint W.; Boydston, Kathy K.

2014-01-01

The decline in population and range of lesser prairie-chickens (Tympanuchus pallidicinctus) throughout the central and southern Great Plains has raised concerns considering their candidate status under the United States Endangered Species Act. Baseline ecological data for lesser prairie-chickens are limited, especially for the shinnery oak-grassland communities of Texas. This information is imperative because lesser prairie-chickens in shinnery oak grasslands occur at the extreme southwestern edge of their distribution. This geographic region is characterized by hot, arid climates, less fragmentation, and less anthropogenic development than within the remaining core distribution of the species. Thus, large expanses of open rangeland with less anthropogenic development and a climate that is classified as extreme for ground nesting birds may subsequently influence nest ecology, nest survival, and nest site selection differently compared to the rest of the distribution of the species. We investigated the nesting ecology of 50 radio-tagged lesser prairie-chicken hens from 2008 to 2011 in the shinnery oak-grassland communities in west Texas and found a substantial amount of inter-annual variation in incubation start date and percent of females incubating nests. Prairie-chickens were less likely to nest near unimproved roads and utility poles and in areas with more bare ground and litter. In contrast, hens selected areas dominated by grasses and shrubs and close to stock tanks to nest. Candidate models including visual obstruction best explained daily nest survival; a 5% increase in visual obstruction improved nest survival probability by 10%. The model-averaged probability of a nest surviving the incubation period was 0.43 (SE = 0.006; 95% CI: 0.23, 0.56). Our findings indicate that lesser prairie-chicken reproduction during our study period was dynamic and was correlated with seasonal weather patterns that ultimately promoted greater grass growth earlier in the

Stability of solid oxide fuel cell materials

Energy Technology Data Exchange (ETDEWEB)

Armstrong, T.R.; Bates, J.L.; Chick, L.A. [Pacific Northwest Lab., Richland, WA (United States)

1996-04-01

Interconnection materials in a solid oxide fuel cell are exposed to both highly oxidizing conditions at the cathode and to highly reducing conditions at the anode. The thermal expansion characteristics of substituted lanthanum and yttrium chromite interconnect materials were evaluated by dilatometry as a function of oxygen partial pressures from 1 atm to 10{sup -18} atm, controlled using a carbon dioxide/hydrogen buffer.

Demonstration of EnergyNest thermal energy storage (TES) technology

Science.gov (United States)

Hoivik, Nils; Greiner, Christopher; Tirado, Eva Bellido; Barragan, Juan; Bergan, Pâl; Skeie, Geir; Blanco, Pablo; Calvet, Nicolas

2017-06-01

This paper presents the experimental results from the EnergyNest 2 × 500 kWhth thermal energy storage (TES) pilot system installed at Masdar Institute of Science & Technology Solar Platform. Measured data are shown and compared to simulations using a specially developed computer program to verify the stability and performance of the TES. The TES is based on a solid-state concrete storage medium (HEATCRETE®) with integrated steel tube heat exchangers cast into the concrete. The unique concrete recipe used in the TES has been developed in collaboration with Heidelberg Cement; this material has significantly higher thermal conductivity compared to regular concrete implying very effective heat transfer, at the same time being chemically stable up to 450 °C. The demonstrated and measured performance of the TES matches the predictions based on simulations, and proves the operational feasibility of the EnergyNest concrete-based TES. A further case study is analyzed where a large-scale TES system presented in this article is compared to two-tank indirect molten salt technology.

Nesting biology of the trap-nesting Neotropical wasp Trypoxylo n(Trypargilum aurifrons Shuckard (Hymenoptera, Crabronidae Biologia da nidificação de Trypoxylon (Trypargilum aurifrons Shuckard (Hymenoptera, Crabronidae em ninhos-armadilhas

Directory of Open Access Journals (Sweden)

Mariana Marchi Santoni

2007-09-01

Full Text Available The present study was carried out in three localities of the state of São Paulo, Brazil: Araras (Dec/03-Dec/06, São Carlos (Nov/04-Nov/06 and Rifaina (Jul/04-Dec/06. Trap-nests were distributed among sites in the sampling areas and were collected every 35 days. Data from 295 nests indicate that T. aurifrons is a multivoltine species, with higher rates of nest building and cell production in the warm, rainy season. The trap-nests used by the females ranged from 117 to 467 mm in length and 3.1 to 16.6 mm in diameter. All nests showed deep plugs and a vestibular cell was found in 37% of the complete nests. The number of cells per nest ranged from one to 12. Females were larger than males, emerged from longer cells and their cocoons were significantly larger. A secondary 1:1 sex ratio was found in Araras and Rifaina. No correlation was observed between the diameter of the trap-nest and sex ratio. Males were usually oviposited in the first brood cells. Male and female developmental time from egg to adult was longer in the cold, dry season. Trypoxylon aurifrons provisioned their nests mainly with orb-spiders from the family Araneidae. The most important mortality factor was the death of immature forms, probably due to development failure. The most important parasitoid was Melittobia sp.Este estudo foi realizado em três localidades do estado de São Paulo: Araras (dez/03-dez/06, São Carlos (nov/04-nov/06 e Rifaina (jul/04-dez/06. Ninhos-armadilhas foram distribuídos em diferentes sítios das áreas amostradas e coletados a cada 35 dias. Dados de 295 ninhos mostraram que T. aurifrons é uma espécie multivoltina, com maiores taxas de nidificação e produção de células na estação quente e chuvosa. Os ninhos-armadilhas utilizados pelas fêmeas variaram de 117 a 467 mm de comprimento e de 3,1 a 16,6 mm de diâmetro. Todos os ninhos apresentaram parede de fundo e célula vestibular foi constatada em 37% dos ninhos completos. O número de c

Conversion of hydrocarbons in solid oxide fuel cells

DEFF Research Database (Denmark)

Mogensen, Mogens Bjerg; Kammer Hansen, K.

2003-01-01

Recently, a number of papers about direct oxidation of methane and hydrocarbon in solid oxide fuel cells (SOFC) at relatively low temperatures (about 700degreesC) have been published. Even though the conversion of almost dry CH4 at 1000degreesC on ceramic anodes was demonstrated more than 10 years...

Differences in predators of artificial and real songbirds nests: Evidence of bias in artificial nest studies

Science.gov (United States)

Frank R. Thompson; Dirk E. Burhans

2004-01-01

In the past two decades, many researchers have used artificial nest to measure relative rates of nest predation. Recent comparisons show that real and artificial nests may not be depredated at the same rate, but no one has examined the mechanisms underlying these patterns. We determined differences in predator-specific predation rates of real and artificial nests. we...

Conservation significance of alternative nests of golden eagles

Directory of Open Access Journals (Sweden)

Brian A. Millsap

2015-01-01

Full Text Available Golden eagles (Aquila chrysaetos are long-lived raptors that maintain nesting territories that may be occupied for a century or longer. Within occupied nesting territories there is one nest in which eagles lay their eggs in a given year (i.e., the used nest, but there are usually other nests (i.e., alternative nests. Conservation plans often protect used nests, but not alternative nests or nesting territories that appear vacant. Our objective is to review literature on golden eagle use of alternative nests and occupancy of nesting territories to determine if alternative nests are biologically significant and warrant greater conservation consideration. Our review shows that: (1 alternative nests or their associated habitat are most often in core areas of golden eagle nesting territories; (2 alternative nests likely will become used in the future; (3 probability of an alternative nest becoming used is greatest where prey availability is high and alternative nest sites are limited; (4 likelihood of annual occupancy or reoccupancy of golden eagle nesting territories is high; and (5 prey availability is the most important determinant of nesting territory occupancy and breeding activity. We recommend alternative nests be treated with the same deference as used nests in land use planning.

Solid oxide fuel cells with bi-layered electrolyte structure

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xinge; Robertson, Mark; Deces-Petit, Cyrille; Xie, Yongsong; Hui, Rob; Qu, Wei; Kesler, Olivera; Maric, Radenka; Ghosh, Dave [Institute for Fuel Cell Innovation, National Research Council Canada, 4250 Wesbrook Mall, Vancouver, B.C. V6T 1W5 (Canada)

2008-01-10

In this work, we have developed solid oxide fuel cells with a bi-layered electrolyte of 2 {mu}m SSZ and 4 {mu}m SDC using tape casting, screen printing, and co-firing processes. The cell reached power densities of 0.54 W cm{sup -2} at 650 C and 0.85 W cm{sup -2} at 700 C, with open circuit voltage (OCV) values larger than 1.02 V. The electrical leaking between anode and cathode through an SDC electrolyte has been blocked in the bi-layered electrolyte structure. However, both the electrolyte resistance (R{sub el}) and electrode polarization resistance (R{sub p,a+c}) increased in comparison to cells with single-layered SDC electrolytes. The formation of a solid solution of (Ce, Zr)O{sub 2-x} during sintering process and the flaws in the bi-layered electrolyte structure seem to be the main causes for the increase in the R{sub el} value (0.32 {omega} cm{sup 2}) at 650 C, which is almost one order of magnitude higher than the calculated value. (author)

Columbia River ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for bird nesting sites in the Columbia River area. Vector points in this data set represent locations of...

Changes in position and quality of preferred nest box: effects on nest box use by laying hens

DEFF Research Database (Denmark)

Riber, Anja Brinch; Nielsen, Birte L.

2013-01-01

Using laying hens, we investigated whether position of a nest box, both within the pen and relative to other nest boxes, influenced the preference for a nest box, and how a sudden and marked change to the preferred box influenced the use of nest boxes by the hens. Groups (n=12) of 15 Isa Warren...... hens were housed in pens, each with five identical nest boxes in different positions: Two single (in a corner or not) and a triplet of nest boxes (one of which in a corner). The use of nest boxes was determined by the number of eggs laid daily in each box. Three experiments, each lasting 10 days, were...... carried out. First, the undisturbed use of each of the nest box types was investigated, and a strong preference (Peggs laid there. Second, each of the hen groups was moved to another pen allocated at random, and where...

Tubular solid oxide fuel cells with porous metal supports and ceramic interconnections

Science.gov (United States)

Huang, Kevin [Export, PA; Ruka, Roswell J [Pittsburgh, PA

2012-05-08

An intermediate temperature solid oxide fuel cell structure capable of operating at from 600.degree. C. to 800.degree. C. having a very thin porous hollow elongated metallic support tube having a thickness from 0.10 mm to 1.0 mm, preferably 0.10 mm to 0.35 mm, a porosity of from 25 vol. % to 50 vol. % and a tensile strength from 700 GPa to 900 GPa, which metallic tube supports a reduced thickness air electrode having a thickness from 0.010 mm to 0.2 mm, a solid oxide electrolyte, a cermet fuel electrode, a ceramic interconnection and an electrically conductive cell to cell contact layer.

Substrates and materials used for nesting by North American Osmia bees (Hymenoptera: Apiformes: Megachilidae)

Science.gov (United States)

James H. Cane; Terry L. Griswold; Frank D. Parker

2007-01-01

Nesting substrates and construction materials are compared for 65 of North America's 139 described native species of Osmia bees. Most accounts report Osmia bees nesting in preexisting cavities in dead wood or pithy stems such as elderberry (Sambucus spp.), with cell partitions and plugs made from a pulp of finely masticated leaf tissue. Mud is widely used by...

First remarks on the nesting biology of Hypodynerus andeus (Packard (Hymenoptera, Vespidae, Eumeninae in the Azapa valley, northern Chile

Directory of Open Access Journals (Sweden)

Felipe Méndez-Abarca

2012-06-01

Full Text Available First remarks on the nesting biology of Hypodynerus andeus (Packard (Hymenoptera, Vespidae, Eumeninae in the Azapa valley, northern Chile. Some aspects about the nesting biology of the potter wasp Hypodynerus andeus (Packard, 1869 are reported for the first time. Observations were carried out at the Azapa valley, coastal desert of northern Chile. A total of sixty nests were collected and examined, each composed by 1-14 cells, most of them found attached to concrete lamp posts. The only preys recorded in the cells were Geometridae (Lepidoptera caterpillars and the presence of the parasitoid Anthrax sp. (Diptera, Bombyliidae was also recorded. A number of arthropods belonging to different groups, mainly spiders, were found occupying empty nests.

Sustained Cytotoxicity of Wogonin on Breast Cancer Cells by Encapsulation in Solid Lipid Nanoparticles

Directory of Open Access Journals (Sweden)

Jong-Suep Baek

2018-03-01

Full Text Available While wogonin has been known to have cytotoxicity against various cancer cells, its bioavailability and cytotoxicity are low due to its low water solubility. Therefore, wogonin-loaded solid lipid nanoparticles were fabricated using a hot-melted evaporation technique. The highest solubility of wogonin was observed in stearic acid. Hence, wogonin-loaded solid lipid nanoparticles were composed of stearic acid as the lipid matrix. The physicochemical properties of the wogonin-loaded solid lipid nanoparticles were evaluated by dynamic laser scattering and scanning electron microscopy. The wogonin-loaded solid lipid nanoparticles exhibited sustained and controlled release up to 72 h. In addition, it was observed that the wogonin-loaded solid lipid nanoparticles exhibited enhanced cytotoxicity and inhibited poly (ADP-ribose polymerase in MCF-7 breast cancer cells. Overall, the results indicate that wogonin-loaded solid lipid nanoparticles could be an efficient delivery system for the treatment of breast cancer.

The influence of regional hydrology on nesting behavior and nest fate of the American alligator

Science.gov (United States)

Ugarte, Cristina A.; Bass, Oron L.; Nuttle, William; Mazzotti, Frank J.; Rice, Kenneth G.; Fujisaki, Ikuko; Whelan, Kevin R.T.

2013-01-01

Hydrologic conditions are critical to the nesting behavior and reproductive success of crocodilians. In South Florida, USA, growing human settlement has led to extensive surface water management and modification of historical water flows in the wetlands, which have affected regional nesting of the American alligator (Alligator mississippiensis). Although both natural and anthropogenic factors are considered to determine hydrologic conditions, the aspects of hydrological patterns that affect alligator nest effort, flooding (partial and complete), and failure (no hatchling) are unclear. We deconstructed annual hydrological patterns using harmonic models that estimated hydrological matrices including mean, amplitude, timing of peak, and periodicity of surface water depth and discharge and examined their effects on alligator nesting using survey data from Shark Slough, Everglades National Park, from 1985 to 2005. Nest effort increased in years with higher mean and lesser periodicity of water depth. A greater proportion of nests were flooded and failed when peak discharge occurred earlier in the year. Also, nest flooding rates were greater in years with greater periodicity of water depth, and nest failure rate was greater when mean discharge was higher. This study guides future water management decisions to mitigate negative impacts on reproduction of alligators and provides wildlife managers with a tool for assessing and modifying annual water management plans to conserve crocodilians and other wetland species.

Lack of nest site limitation in a cavity-nesting bird community

Science.gov (United States)

Jeffry R. Waters; Barry R. Noon; Jared Verner

1990-01-01

We examined the relationship between nest site availability and density of secondary cavitynesting birds by blocking cavities in an oak-pine (Quercus spp.-Pinus sp. ) woodland. In 1986 and 1987we blocked 67 and 106 cavities, respectively, on a 37-ha plot. The combined density of secondary cavity-nesting birds did not decline...

SOLID STATE ENERGY CONVERSION ALLIANCE DELPHI SOLID OXIDE FUEL CELL

Energy Technology Data Exchange (ETDEWEB)

Steven Shaffer; Sean Kelly; Subhasish Mukerjee; David Schumann; Gail Geiger; Kevin Keegan; Larry Chick

2004-05-07

The objective of this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with the option of piped-in water (Demonstration System A). Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from July 1, 2003 to December 31, 2003, under Department of Energy Cooperative Agreement DE-FC-02NT41246. This report highlights technical results of the work performed under the following tasks: Task 1 System Design and Integration; Task 2 Solid Oxide Fuel Cell Stack Developments; Task 3 Reformer Developments; Task 4 Development of Balance of Plant (BOP) Components; Task 5 Manufacturing Development (Privately Funded); Task 6 System Fabrication; Task 7 System Testing; Task 8 Program Management; Task 9 Stack Testing with Coal-Based Reformate; and Task 10 Technology Transfer from SECA CORE Technology Program. In this reporting period, unless otherwise noted Task 6--System Fabrication and Task 7--System Testing will be reported within Task 1 System Design and Integration. Task 8--Program Management, Task 9--Stack Testing with Coal Based Reformate, and Task 10--Technology Transfer from SECA CORE Technology Program will be reported on in the Executive Summary section of this report.

Organic dye for highly efficient solid-state dye-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Schmidt-Mende, L.; Bach, U.; Humphry-Baker, R.; Ito, S.; Graetzel, M. [Institut des Sciences et Ingenierie Chimiques (ISIC), Laboratoire de Photonique et Interfaces (LPI), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Horiuchi, T.; Miura, H. [Technology Research Laboratory, Corporate Research Center, Mitsubishi Paper Mills Limited, 46, Wadai, Tsukuba City, Ibaraki 300-4247 (Japan); Uchida, S. [Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 1-1 Katahira 2-chome, Aoba-ku, Sendai 980-8577 (Japan)

2005-04-04

The feasibility of solid-state dye-sensitized solar cells as a low-cost alternative to amorphous silicon cells is demonstrated. Such a cell with a record efficiency of over 4 % under simulated sunlight is reported, made possible by using a new organic metal-free indoline dye as the sensitizer with high absorption coefficient. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

Durability evaluation of reversible solid oxide cells

Science.gov (United States)

Zhang, Xiaoyu; O'Brien, James E.; O'Brien, Robert C.; Housley, Gregory K.

2013-11-01

An experimental investigation on the performance and durability of single solid oxide cells (SOCs) is under way at the Idaho National Laboratory. Reversible operation of SOCs includes electricity generation in the fuel cell mode and hydrogen generation in the electrolysis mode. Degradation is a more significant issue when operating SOCs in the electrolysis mode. In order to understand and mitigate the degradation issues in high temperature electrolysis, single SOCs with different configurations from several manufacturers have been evaluated for initial performance and long-term durability. Cells were obtained from four industrial partners. Cells from Ceramatec Inc. and Materials and Systems Research Inc. (MSRI) showed improved durability in electrolysis mode compared to previous stack tests. Cells from Saint Gobain Advanced Materials Inc. (St. Gobain) and SOFCPower Inc. demonstrated stable performance in the fuel cell mode, but rapid degradation in the electrolysis mode, especially at high current density. Electrolyte-electrode delamination was found to have a significant impact on degradation in some cases. Enhanced bonding between electrolyte and electrode and modification of the electrode microstructure helped to mitigate degradation. Polarization scans and AC impedance measurements were performed during the tests to characterize cell performance and degradation.

Poisoning of Solid Oxide Electrolysis Cells by Impurities

DEFF Research Database (Denmark)

Ebbesen, Sune; Graves, Christopher R.; Hauch, Anne

2010-01-01

Electrolysis of H2O, CO2, and co-electrolysis of H2O and CO2 was studied in Ni/yttria-stabilized zirconia (YSZ) electrode supported solid oxide electrolysis cells (SOECs) consisting of a Ni/YSZ support, a Ni/YSZ electrode layer, a YSZ electrolyte, and an lanthanum strontium manganite (LSM)/YSZ ox...

Nest design in a changing world: great tit Parus major nests from a Mediterranean city environment as a case study.

Science.gov (United States)

Lambrechts, Marcel M; Charmantier, Anne; Demeyrier, Virginie; Lucas, Annick; Perret, Samuel; Abouladzé, Matthieu; Bonnet, Michel; Canonne, Coline; Faucon, Virginie; Grosset, Stéphanie; le Prado, Gaëlle; Lidon, Frédéric; Noell, Thierry; Pagano, Pascal; Perret, Vincent; Pouplard, Stéphane; Spitaliéry, Rémy; Bernard, Cyril; Perret, Philippe; Blondel, Jacques; Grégoire, Arnaud

2017-12-01

Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban environments are expected to present novel environmental changes relative to rural environments, it is important to evaluate how nest-building behavior is impacted by vegetation modifications associated with urbanization. To examine nest design in a Mediterranean city environment, we allowed urban great tits ( Parus major ) to breed in nest boxes in areas that differed in local vegetation cover. We found that different measures of nest size or mass were not associated with vegetation cover. In particular, nests located adjacent to streets with lower vegetation cover were not smaller or lighter than nests in parks with higher vegetation cover. Nests adjacent to streets contained more pine needles than nests in parks. In addition, in nests adjacent to streets, nests from boxes attached to pine trees contained more pine needles than nests from boxes attached to other trees. We suggest that urban-related alterations in vegetation cover do not directly impose physical limits on nest size in species that are opportunistic in the selection of nesting material. However, nest composition as reflected in the use of pine needles was clearly affected by habitat type and the planted tree species present, which implies that rapid habitat change impacts nest composition. We do not exclude that urbanization might impact other aspects of nest building behaviour not covered in our study (e.g. costs of searching for nest material), and that the strengths of the associations between urbanization and nest structures might differ among study populations or species.

Decoration Increases the Conspicuousness of Raptor Nests.

Science.gov (United States)

Canal, David; Mulero-Pázmány, Margarita; Negro, Juan José; Sergio, Fabrizio

2016-01-01

Avian nests are frequently concealed or camouflaged, but a number of species builds noticeable nests or use conspicuous materials for nest decoration. In most cases, nest decoration has a role in mate choice or provides thermoregulatory or antiparasitic benefits. In territorial species however, decorations may serve additional or complementary functions, such as extended phenotypic signaling of nest-site occupancy and social status to potential intruders. The latter may benefit both signaler and receiver by minimizing the risk of aggressive interactions, especially in organisms with dangerous weaponry. Support for this hypothesis was recently found in a population of black kites (Milvus migrans), a territorial raptor that decorates its nest with white artificial materials. However, the crucial assumption that nest decorations increased nest-site visibility to conspecifics was not assessed, a key aspect given that black kite nests may be well concealed within the canopy. Here, we used an unmanned aircraft system to take pictures of black kite nests, with and without an experimentally placed decoration, from different altitudes and distances simulating the perspective of a flying and approaching, prospecting intruder. The pictures were shown to human volunteers through a standardized routine to determine whether detection rates varied according the nest decoration status and distance. Decorated nests consistently showed a higher detection frequency and a lower detection-latency, compared to undecorated versions of the same nests. Our results confirm that nest decoration in this species may act as a signaling medium that enhances nest visibility for aerial receivers, even at large distances. This finding complements previous work on this communication system, which showed that nest decoration was a threat informing trespassing conspecifics on the social dominance, territory quality and fighting capabilities of the signaler.

Nest defense behaviors of native cavity-nesting birds to European Starlings

Science.gov (United States)

Rodney G. Olsen; Kathryn L. Purcell; David. Grubbs

2008-01-01

We used behavioral experiments to evaluate competition for nest sites and the extent to which European Starlings (Sturnus vulgaris) are seen as a threat by native bird species at the San Joaquin Experimental Range, Madera County, CA. We quantified the level of aggressive behavior of four species of native cavity-nesting birds to starlings at active...

Use of artificial nests to investigate predation on freshwater turtle nests

Science.gov (United States)

Michael N. Marchand; John A. Litvaitis; Thomas J. Maier; Richard M. DeGraaf

2002-01-01

Habitat fragmentation has raised concerns that populations of generalist predators have increased and are affecting a diverse group of prey. Previous research has included the use of artificial nests to investigate the role of predation on birds that nest on or near the ground. Because predation also is a major factor limiting populations of freshwater turtles, we...

Interspecific nest use by aridland birds

Science.gov (United States)

Deborah M. Finch

1982-01-01

Nest holes drilled by woodpeckers (Picidae) are frequently used by secondary cavity-nesting species, but interspecific use of open and domed nests is less well known. Nests constructed by many southwestern desert birds last longer than one year (pers. obs.) and are consequently reused by the same pair (e.g., Abert's Towhees [Pipilo aberti], pers. obs.) or by other...

Enhancement of the photoelectric performance in inverted bulk heterojunction solid solar cell with inorganic nanocrystals

International Nuclear Information System (INIS)

Luan, Weiling; Zhang, Chengxi; Luo, Lingli; Yuan, Binxia; Jin, Lin; Kim, Yong-Sang

2017-01-01

Highlights: • Solid solar cells based on FeS_2 or PbS NCs showed power conversion efficiency (PCE) of 3.0% and 3.11%, respectively. • The FeS_2 NCs/polymer solar cells showed good time and thermal stability when exposed in air condition. • Ternary solid solar cells based on PbS NCs exhibited a higher short circuit current density (J_s_c). - Abstract: Nanocrystal/polymer solid solar cells have the advantages of low-cost, simple process, and flexible manufacture. In this work, ternary solid solar cells based on FeS_2 and PbS nanocrystals exhibited photovoltaic conversion efficiency of 3.0% and 3.1%, respectively. As a kind of semiconductor with optical absorption in the visible and near-infrared regions, FeS_2 nanocrystals matched well with the solar radiation spectrum. Furthermore, PbS Nanocrystals could increase the number of electrons, due to its multiple exciton effect. Additionally, the FeS_2 nanocrystals solar cells showed high stability, with 83.3% of its initial efficiency remained after 15 weeks of exposure in air, and kept good stable performance at 20–80 °C. The photovoltaic conversion efficiency fluctuation magnitudes were also found to be smaller than quantum-dot sensitized solar cell under the same conditions.

Induction of oncogene addiction shift to NF-κB by camptothecin in solid tumor cells

International Nuclear Information System (INIS)

Togano, Tomiteru; Sasaki, Masataka; Watanabe, Mariko; Nakashima, Makoto; Tsuruo, Takashi; Umezawa, Kazuo; Higashihara, Masaaki; Watanabe, Toshiki; Horie, Ryouichi

2009-01-01

The biological basis of the resistance of solid tumor cells to chemotherapy is not well understood. While addressing this problem, we found that gastric cancer cell line St-4/CPT, lung cancer cell line A549/CPT, and colon cancer cell line HT-29/CPT, all of which are resistant to camptothecin (CPT), showed strong and constitutive nuclear factor (NF)-κB activity driven by IκB kinase compared with their parental cell lines St-4, A549, and HT-29. A new NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), reduced viability and induced apoptosis in St-4/CPT, A549/CPT, and HT-29/CPT cell lines, while their parental cell lines were resistant to DHMEQ. The results in this study present an example of the shift in signals that support the survival of solid tumor cells to NF-κB during the acquisition of resistance to CPT. The results also indicate that solid tumor cells that become resistant to chemotherapy may be more easily treated by NF-κB inhibitors.

Induction of oncogene addiction shift to NF-{kappa}B by camptothecin in solid tumor cells

Energy Technology Data Exchange (ETDEWEB)

Togano, Tomiteru; Sasaki, Masataka; Watanabe, Mariko; Nakashima, Makoto [Department of Hematology, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Tsuruo, Takashi [Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Umezawa, Kazuo [Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-0061 (Japan); Higashihara, Masaaki [Department of Hematology, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Watanabe, Toshiki [Laboratory of Tumor Cell Biology, Department of Medical Genome Sciences, Graduate School of Frontier Sciences, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Horie, Ryouichi, E-mail: rhorie@med.kitasato-u.ac.jp [Department of Hematology, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan)

2009-12-04

The biological basis of the resistance of solid tumor cells to chemotherapy is not well understood. While addressing this problem, we found that gastric cancer cell line St-4/CPT, lung cancer cell line A549/CPT, and colon cancer cell line HT-29/CPT, all of which are resistant to camptothecin (CPT), showed strong and constitutive nuclear factor (NF)-{kappa}B activity driven by I{kappa}B kinase compared with their parental cell lines St-4, A549, and HT-29. A new NF-{kappa}B inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), reduced viability and induced apoptosis in St-4/CPT, A549/CPT, and HT-29/CPT cell lines, while their parental cell lines were resistant to DHMEQ. The results in this study present an example of the shift in signals that support the survival of solid tumor cells to NF-{kappa}B during the acquisition of resistance to CPT. The results also indicate that solid tumor cells that become resistant to chemotherapy may be more easily treated by NF-{kappa}B inhibitors.

Cleaner mites: sanitary mutualism in the miniature ecosystem of neotropical bee nests.

Science.gov (United States)

Biani, Natalia B; Mueller, Ulrich G; Wcislo, William T

2009-06-01

Cleaning symbioses represent classic models of mutualism, and some bee mites are thought to perform cleaning services for their hosts in exchange for suitable environments for reproduction and dispersal. These mutual benefits, however, have not been rigorously demonstrated. We tested the sanitary role of bee mites by correlating mite loads with fungal contamination in natural nests of Megalopta genalis and Megalopta ecuadoria and by experimentally manipulating mite loads in artificial cells with developing brood. Field observations revealed significant correlations between the presence of mites and the absence of fungi inside the brood cells, as well as between the absence of mites and increased bee mortality. Likewise, experimental brood cells with mites have fewer fungal colonies than do cells without mites. Field observations and experimental manipulations, therefore, provide clear evidence of the sanitary effect of mites in nests of Megalopta bees. This bee-mite association constitutes one of the few examples of terrestrial cleaning mutualisms.

Preliminary evaluation of a nest usage sensor to detect double nest occupations of laying hens.

Science.gov (United States)

Zaninelli, Mauro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Agazzi, Alessandro; Savoini, Giovanni

2015-01-26

Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens' welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage "sensor", based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

Preliminary Evaluation of a Nest Usage Sensor to Detect Double Nest Occupations of Laying Hens

Directory of Open Access Journals (Sweden)

Mauro Zaninelli

2015-01-01

Full Text Available Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens’ welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage “sensor”, based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

Nest densities of cavity-nesting birds in relation to postfire salvage logging and time since wildfire

Science.gov (United States)

Victoria A. Saab; Robin E. Russell; Jonathan G. Dudley

2007-01-01

We monitored the nest densities and nest survival of seven cavity-nesting bird species, including four open-space foragers (American Kestrel [Falco sparverius], Lewis's Woodpecker [Melanerpes lewis], Western Bluebird [Sialia mexicana], and Mountain Bluebird [S. currucoides]) and three wood...

Notes on the nesting of three species of Megachilinae in the Dubai Desert Conservation Reserve, UAE

Directory of Open Access Journals (Sweden)

Sarah Kathleen Gess

2017-02-01

Full Text Available Some observations on the nesting of three species belonging to phylogenetically interesting lineages of Megachilinae are presented. Published knowledge of the nesting of these species, Megachile (Maximegachile maxillosa Guérin-Méneville (Megachilini, Megachile (Eurymella patellimana Spinola (Megachilini, and Pseudoheriades grandiceps Peters (currently assigned to the Osmiini, is fragmentary making the notes presented here a worthwhile addition. The brood cells of M. maxillosa and of P. grandiceps, constructed from a mixture of resin and sand, were positioned in pre-existing cavities, trap-nests, above ground. The cells of the former are equal in diameter to the boring and are constructed in linear series. Those of the latter are small ovoid and are grouped to form a cluster. Megachile patellimana was nesting in burrows in compacted sandy ground beneath a plant and in the banks of an irrigation furrow. At the former site a female was carrying a freshly cut leaf piece and at the latter another was carrying a cut length of narrow, tough, green plastic. The nest contained a group of identical lengths of plastic, clearly a substitute for leaves.

Contrasting Effects of Cattle Grazing Intensity on Upland-Nesting Duck Production at Nest and Field Scales in the Aspen Parkland, Canada

Directory of Open Access Journals (Sweden)

Jeffrey M. Warren

2008-12-01

Full Text Available The Aspen Parkland of Canada is one of the most important breeding areas for temperate nesting ducks in North America. The region is dominated by agricultural land use, with approximately 9.3 million ha in pasture land for cattle grazing. However, the effects of using land for cattle grazing on upland-nesting duck production are poorly understood. The current study was undertaken during 2001 and 2002 to investigate how nest density and nesting success of upland-nesting ducks varied with respect to the intensity of cattle grazing in the Aspen Parkland. We predicted that the removal and trampling of vegetation through cattle grazing would reduce duck nest density. Both positive and negative responses of duck nesting success to grazing have been reported in previous studies, leading us to test competing hypotheses that nesting success would (1 decline linearly with grazing intensity or (2 peak at moderate levels of grazing. Nearly 3300 ha of upland cover were searched during the study. Despite extensive and severe drought, nest searches located 302 duck nests. As predicted, nest density was higher in fields with lower grazing intensity and higher pasture health scores. A lightly grazed field with a pasture score of 85 out of a possible 100 was predicted to have 16.1 nests/100 ha (95% CI = 11.7-22.1, more than five times the predicted nest density of a heavily grazed field with a pasture score of 58 (3.3 nests/100 ha, 95% CI = 2.2-4.5. Nesting success was positively related to nest-site vegetation density across most levels of grazing intensity studied, supporting our hypothesis that reductions in vegetation caused by grazing would negatively affect nesting success. However, nesting success increased with grazing intensity at the field scale. For example, nesting success for a well-concealed nest in a lightly grazed field was 11.6% (95% CI = 3.6-25.0%, whereas nesting success for a nest with the same level of nest-site vegetation in a heavily grazed

Improving CART-Cell Therapy of Solid Tumors with Oncolytic Virus-Driven Production of a Bispecific T-cell Engager.

Science.gov (United States)

Wing, Anna; Fajardo, Carlos Alberto; Posey, Avery D; Shaw, Carolyn; Da, Tong; Young, Regina M; Alemany, Ramon; June, Carl H; Guedan, Sonia

2018-05-01

T cells expressing chimeric antigen receptors (CART) have shown significant promise in clinical trials to treat hematologic malignancies, but their efficacy in solid tumors has been limited. Oncolytic viruses have the potential to act in synergy with immunotherapies due to their immunogenic oncolytic properties and the opportunity of incorporating therapeutic transgenes in their genomes. Here, we hypothesized that an oncolytic adenovirus armed with an EGFR-targeting, bispecific T-cell engager (OAd-BiTE) would improve the outcome of CART-cell therapy in solid tumors. We report that CART cells targeting the folate receptor alpha (FR-α) successfully infiltrated preestablished xenograft tumors but failed to induce complete responses, presumably due to the presence of antigen-negative cancer cells. We demonstrated that OAd-BiTE-mediated oncolysis significantly improved CART-cell activation and proliferation, while increasing cytokine production and cytotoxicity, and showed an in vitro favorable safety profile compared with EGFR-targeting CARTs. BiTEs secreted from infected cells redirected CART cells toward EGFR in the absence of FR-α, thereby addressing tumor heterogeneity. BiTE secretion also redirected CAR-negative, nonspecific T cells found in CART-cell preparations toward tumor cells. The combinatorial approach improved antitumor efficacy and prolonged survival in mouse models of cancer when compared with the monotherapies, and this was the result of an increased BiTE-mediated T-cell activation in tumors. Overall, these results demonstrated that the combination of a BiTE-expressing oncolytic virus with adoptive CART-cell therapy overcomes key limitations of CART cells and BiTEs as monotherapies in solid tumors and encourage its further evaluation in human trials. Cancer Immunol Res; 6(5); 605-16. ©2018 AACR . ©2018 American Association for Cancer Research.

Concentration Impedance in Testing of Solid Oxide Cells Revisited

DEFF Research Database (Denmark)

Mogensen, Mogens Bjerg; Ebbesen, Sune Dalgaard; Jensen, Søren Højgaard

2017-01-01

The concentration impedance originating from diffusion and reactant conversion impedance of the Ni-YSZ supported fuel electrode in solid oxide cell has been treated many times during the latest couple of decades. In spite of this, the separation of the diffusion impedance from the conversion...

Lessons learned: from dye-sensitized solar cells to all-solid-state hybrid devices.

Science.gov (United States)

Docampo, Pablo; Guldin, Stefan; Leijtens, Tomas; Noel, Nakita K; Steiner, Ullrich; Snaith, Henry J

2014-06-25

The field of solution-processed photovoltaic cells is currently in its second spring. The dye-sensitized solar cell is a widely studied and longstanding candidate for future energy generation. Recently, inorganic absorber-based devices have reached new record efficiencies, with the benefits of all-solid-state devices. In this rapidly changing environment, this review sheds light on recent developments in all-solid-state solar cells in terms of electrode architecture, alternative sensitizers, and hole-transporting materials. These concepts are of general applicability to many next-generation device platforms. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Strategies for enhancing adoptive T-cell immunotherapy against solid tumors using engineered cytokine signaling and other modalities.

Science.gov (United States)

Shum, Thomas; Kruse, Robert L; Rooney, Cliona M

2018-05-04

Cancer therapy has been transformed by the demonstration that tumor-specific T-cells can eliminate tumor cells in a clinical setting with minimal long-term toxicity. However, significant success in the treatment of leukemia and lymphoma with T-cells using native receptors or redirected with chimeric antigen receptors (CARs) has not been recapitulated in the treatment of solid tumors. This lack of success is likely related to the paucity of costimulatory and cytokine signaling available in solid tumors, in addition to a range of inhibitory mechanisms. Areas covered: We summarize the latest developments in engineered T-cell immunotherapy, describe the limitations of these approaches in treating solid tumors, and finally highlight several strategies that may be useful in mediating solid tumor responses in the future, while also ensuring safety of engineered cells. Expert opinion: CAR-T therapies require further engineering to achieve their potential against solid tumors. Facilitating cytokine signaling in CAR T-cells appears to be essential in achieving better responses. However, the engineering of T-cells with potentially unchecked proliferation and potency raises the question of whether the simultaneous combination of enhancements will prove safe, necessitating continued advancements in regulating CAR-T activity at the tumor site and methods to safely switch off these engineered cells.

Chimeric antigen receptor-modified T cells for the treatment of solid tumors: Defining the challenges and next steps☆

OpenAIRE

Beatty, Gregory L.; O’Hara, Mark

2016-01-01

Chimeric antigen receptor (CAR) T cell therapy has shown promise in CD19 expressing hematologic malignancies, but how to translate this success to solid malignancies remains elusive. Effective translation of CAR T cells to solid tumors will require an understanding of potential therapeutic barriers, including factors that regulate CAR T cells expansion, persistence, trafficking, and fate within tumors. Herein, we describe the current state of CAR T cells in solid tumors; define key barriers t...

Nesting ecology of Arctic loons

Science.gov (United States)

Petersen, Margaret R.

1979-01-01

Arctic Loons were studied on the Yukon-Kuskokwim Delta, Alaska, from the time of their arrival in May to their departure in September, in 1974 and 1975. Pairs arrived on breeding ponds as soon as sufficient meltwater was available to allow their take-off and landing. Loons apparently do not initiate nests immediately after their arrival, even when nest-sites are available. Delayed egg-laying may be dependent on a period of yolk formation. Delaying yolk formation until after arrival on nest ponds is an adaptation by loons to the variable time suitable habitat becomes available for nesting. Predation of eggs by Glaucous Gulls, Long-tailed and Parasitic jaegers and foxes varied in relation to the location of the nest-site, and the availability of alternate prey. Hatching success was the lowest recorded for Arctic Loons (5%) in 1974, when eggs of both loons and Cackling Geese were taken in large numbers by predators. Hatching success increased to 32% in 1975 when an abundance of tundra voles was observed. No loon eggs hatched after the hatching of the Cackling Goose eggs when this alternate prey was no longer available. Nests destroyed by foxes were predominantly along shorelines, and those by gulls and jaegers were predominantly on islands. Nest-site selection by Arctic Loons may reflect an adaptive response to varying selective pressures by their predators.

Nest-site selection in the acorn woodpecker

Science.gov (United States)

Hooge, P.N.; Stanback, M.T.; Koenig, Walter D.

1999-01-01

Acorn Woodpeckers (Melanerpes formicivorus) at Hastings Reservation in central California prefer to nest in dead limbs in large, dead valley oaks (Quercus lobata) and California sycamores (Platanus racemosa) that are also frequently used as acorn storage trees. Based on 232 nest cavities used over an 18-year period, we tested whether preferred or modal nest-site characters were associated with increased reproductive success (the "nest-site quality" hypothesis). We also examined whether more successful nests were likely to experience more favorable microclimatic conditions or to be less accessible to terrestrial predators. We found only equivocal support for the nest-site quality hypothesis: only 1 of 5 preferred characters and 2 of 10 characters exhibiting a clear modality were correlated with higher reproductive success. All three characteristics of nests known or likely to be associated with a more favorable microclimate, and two of five characteristics likely to render nests less accessible to predators, were correlated with higher reproductive success. These results suggest that nest cavities in this population are built in part to take advantage of favorable microclimatic conditions and, to a lesser extent, to reduce access to predators. However, despite benefits of particular nest characteristics, birds frequently nested in apparently suboptimal cavities. We also found a significant relationship between mean group size and the history of occupancy of particular territories and the probability of nest cavities being built in microclimatically favorable live limbs, suggesting that larger groups residing on more stable territories were better able to construct nests with optimal characteristics. This indicates that there may be demographic, as well as ecological, constraints on nest-site selection in this primary cavity nester.

Strategies for Lowering Solid Oxide Fuel Cells Operating Temperature

Directory of Open Access Journals (Sweden)

Albert Tarancón

2009-11-01

Full Text Available Lowering the operating temperature of solid oxide fuel cells (SOFCs to the intermediate range (500–700 ºC has become one of the main SOFC research goals. High operating temperatures put numerous requirements on materials selection and on secondary units, limiting the commercial development of SOFCs. The present review first focuses on the main effects of reducing the operating temperature in terms of materials stability, thermo-mechanical mismatch, thermal management and efficiency. After a brief survey of the state-of-the-art materials for SOFCs, attention is focused on emerging oxide-ionic conductors with high conductivity in the intermediate range of temperatures with an introductory section on materials technology for reducing the electrolyte thickness. Finally, recent advances in cathode materials based on layered mixed ionic-electronic conductors are highlighted because the decreasing temperature converts the cathode into the major source of electrical losses for the whole SOFC system. It is concluded that the introduction of alternative materials that would enable solid oxide fuel cells to operate in the intermediate range of temperatures would have a major impact on the commercialization of fuel cell technology.

Nest-site competition between invasive and native cavity nesting birds and its implication for conservation.

Science.gov (United States)

Charter, Motti; Izhaki, Ido; Ben Mocha, Yitzchak; Kark, Salit

2016-10-01

Nesting cavities are often a limited resource that multiple species use. There is an ongoing discussion on whether invasive cavity nesting birds restrict the availability of this key limited resource. While the answer to this question has important conservation implications, little experimental work has been done to examine it. Here, we aimed to experimentally test whether alien cavity nesting birds affect the occupancy of cavities and the resulting breeding success of native cavity breeders in a large urban park located in Tel Aviv, Israel. Over three breeding seasons, we manipulated the entry size of nest boxes and compared the occupancy and breeding success of birds in nest boxes of two treatments. These included nest boxes with large-entrance and small-entrance holes. The large-entrance holes allowed access for both the native and invasive birds (the two main aliens in the park are the common mynas and rose-ringed parakeets). The smaller-entrance boxes, on the other hand, allowed only the smaller sized native cavity breeders (great tits and house sparrows) to enter the boxes but prevented the alien species from entering. We found that the large-entrance nest boxes were occupied by five different bird species, comprising three natives (great tit, house sparrow, Scops owl) and two invasive species (common myna, rose-ringed parakeet) while the small-entrance boxes were only occupied by the two native species. The alien common mynas and rose-ringed parakeets occupied 77.5% of the large-entrance nest boxes whereas native species, mainly great tits, occupied less than 9% of the large-entrance boxes and 36.5% of the small-entrance boxes. When examining the occupancy of those cavities that were not occupied by the aliens, natives occupied both the small and large-entrance nest boxes equally. Three quarters (78%) of the great tits breeding in the large-entrance boxes were usurped by common mynas during the breeding season and as a result breeding success was

Where to nest? Ecological determinants of chimpanzee nest abundance and distribution at the habitat and tree species scale.

Science.gov (United States)

Carvalho, Joana S; Meyer, Christoph F J; Vicente, Luis; Marques, Tiago A

2015-02-01

Conversion of forests to anthropogenic land-uses increasingly subjects chimpanzee populations to habitat changes and concomitant alterations in the plant resources available to them for nesting and feeding. Based on nest count surveys conducted during the dry season, we investigated nest tree species selection and the effect of vegetation attributes on nest abundance of the western chimpanzee, Pan troglodytes verus, at Lagoas de Cufada Natural Park (LCNP), Guinea-Bissau, a forest-savannah mosaic widely disturbed by humans. Further, we assessed patterns of nest height distribution to determine support for the anti-predator hypothesis. A zero-altered generalized linear mixed model showed that nest abundance was negatively related to floristic diversity (exponential form of the Shannon index) and positively with the availability of smaller-sized trees, reflecting characteristics of dense-canopy forest. A positive correlation between nest abundance and floristic richness (number of plant species) and composition indicated that species-rich open habitats are also important in nest site selection. Restricting this analysis to feeding trees, nest abundance was again positively associated with the availability of smaller-sized trees, further supporting the preference for nesting in food tree species from dense forest. Nest tree species selection was non-random, and oil palms were used at a much lower proportion (10%) than previously reported from other study sites in forest-savannah mosaics. While this study suggests that human disturbance may underlie the exclusive arboreal nesting at LCNP, better quantitative data are needed to determine to what extent the construction of elevated nests is in fact a response to predators able to climb trees. Given the importance of LCNP as refuge for Pan t. verus our findings can improve conservation decisions for the management of this important umbrella species as well as its remaining suitable habitats. © 2014 Wiley Periodicals, Inc.

Electrochemical Synthesis of Ammonia in Solid Electrolyte Cells

Directory of Open Access Journals (Sweden)

Ioannis eGaragounis

2014-01-01

Full Text Available Developed in the early 1900's, the Haber-Bosch synthesis is the dominant NH3 synthesis process. Parallel to catalyst optimization, current research efforts are also focused on the investigation of new methods for ammonia synthesis, including the electrochemical synthesis with the use of solid electrolyte cells. Since the first report on Solid State Ammonia Synthesis (SSAS, more than 30 solid electrolyte materials were tested and at least 15 catalysts were used as working electrodes. Thus far, the highest rate of ammonia formation reported is 1.13×10−8 mol s−1 cm−2, obtained at 80°C with a Nafion solid electrolyte and a mixed oxide, SmFe0.7Cu0.1Ni0.2O3, cathode. At high temperatures (>500oC the maximum rate was 9.5*10-9 mol s−1 cm−2 using Ce0.8Y0.2O2-δ -[Ca3(PO42 -K3PO4] as electrolyte and Ag-Pd as cathode. In this paper, the advantages and the disadvantages of SSAS vs the conventional process and the requirements that must be met in order to promote the electrochemical process into an industrial level, are discussed.

Electrochemical Synthesis of Ammonia in Solid Electrolyte Cells

International Nuclear Information System (INIS)

Garagounis, Ioannis; Kyriakou, Vasileios; Skodra, Aglaia; Vasileiou, Eirini; Stoukides, Michael

2014-01-01

Developed in the early 1900s, the “Haber–Bosch” synthesis is the dominant NH 3 synthesis process. Parallel to catalyst optimization, current research efforts are also focused on the investigation of new methods for ammonia synthesis, including the electrochemical synthesis with the use of solid electrolyte cells. Since the first report on Solid State Ammonia Synthesis (SSAS), more than 30 solid electrolyte materials were tested and at least 15 catalysts were used as working electrodes. Thus far, the highest rate of ammonia formation reported is 1.13 × 10 -8 mol s -1 cm -2 , obtained at 80°C with a Nafion solid electrolyte and a mixed oxide, SmFe 0.7 Cu 0.1 Ni 0.2 O 3 , cathode. At high temperatures (>500°C), the maximum rate was 9.5 × 10 −9 mol s -1 cm -2 using Ce 0.8 Y 0.2 O 2-δ –[Ca 3 (PO 4 ) 2 –K 3 PO 4 ] as electrolyte and Ag–Pd as cathode. In this paper, the advantages and the disadvantages of SSAS vs. the conventional process and the requirements that must be met in order to promote the electrochemical process into an industrial level are discussed.

Ant colonies prefer infected over uninfected nest sites

DEFF Research Database (Denmark)

Pontieri, Luigi; Vojvodic, Svjetlana; Graham, Riley

2014-01-01

with sporulating mycelium of the entomopathogenic fungus Metarhizium brunneum (infected nests), nests containing nestmates killed by freezing (uninfected nests), and empty nests. In contrast to the expectation pharaoh ant colonies preferentially (84%) moved into the infected nest when presented with the choice...... the high risk of epidemics in group-living animals. Choosing nest sites free of pathogens is hypothesized to be highly efficient in invasive ants as each of their introduced populations is often an open network of nests exchanging individuals (unicolonial) with frequent relocation into new nest sites...... and low genetic diversity, likely making these species particularly vulnerable to parasites and diseases. We investigated the nest site preference of the invasive pharaoh ant, Monomorium pharaonis, through binary choice tests between three nest types: nests containing dead nestmates overgrown...

Serenbe Nest Cottages

Energy Technology Data Exchange (ETDEWEB)

Butler, T.; Curtis, O.; Kim, E.; Roberts, S.; Stephenson, R.

2012-12-01

As part of the NAHB Research Center Industry Partnership, Southface partnered with Martin Dodson Builders and the Serenbe community on the construction of a new test home in the suburbs of Atlanta, GA in the mixed humid climate zone. The most recent subdivision within the Serenbe community, the Nest, will contain 15 small footprint cottage style homes, and Southface has selected Lot Nine, as the test home for this study. This Nest subdivision serves as a project showcase for both the builder partner and the Serenbe community as a whole. The planning and design incorporated into the Nest cottages will be implemented in each home within the subdivision. These homes addresses Building America Savings targets and serve as a basis of design for other homes Martin Dodson plans to build within the Serenbe community.

Serenbe Nest Cottages

Energy Technology Data Exchange (ETDEWEB)

Butler, T. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Curtis, O. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Kim, E. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Roberts, S. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Stephenson, R. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States)

2012-12-01

As part of the NAHB Research Center Industry Partnership, Southface partnered with Martin Dodson Builders and the Serenbe community on the construction of a new test home in the suburbs of Atlanta, GA, in the mixed humid climate zone. The most recent subdivision within the Serenbe community, the Nest, will contain 15 small footprint cottage-style homes, and Southface has selected Lot Nine, as the test home for this study. This Nest subdivision serves as a project showcase for both the builder partner and the Serenbe community as a whole. The planning and design incorporated into the Nest cottages will be implemented in each home within the subdivision. These homes addresses Building America savings targets and serve as a basis of design for other homes Martin Dodson plans to build within the Serenbe community.

Conservation significance of alternative nests of golden eagles

Science.gov (United States)

Brian A. Millsap; Teryl G. Grubb; Robert K. Murphy; Ted Swem; James W. Watson

2015-01-01

Golden eagles (Aquila chrysaetos) are long-lived raptors that maintain nesting territories that may be occupied for a century or longer. Within occupied nesting territories there is one nest in which eagles lay their eggs in a given year (i.e., the used nest), but there are usually other nests (i.e., alternative nests). Conservation plans often protect used nests, but...

Detection of Tumor Markers in Prostate Cancer and Comparison of Sensitivity between Real Time and Nested PCR

OpenAIRE

Matsuoka, Takayuki; Shigemura, Katsumi; Yamamichi, Fukashi; Fujisawa, Masato; Kawabata, Masato; Shirakawa, Toshiro

2012-01-01

The objective of this study is to investigate and compare the sensitivity in conventional PCR, quantitative real time PCR, nested PCR and western blots for detection of prostate cancer tumor markers using prostate cancer (PCa) cells. We performed conventional PCR, quantitative real time PCR, nested PCR, and western blots using 5 kinds of PCa cells. Prostate specific antigen (PSA), prostate specific membrane antigen (PSMA), and androgen receptor (AR) were compared for their detection sensitivi...

Nesting of the Blakiston's Fish-Owl in the Nest of the Steller’s Sea Eagle, Magadan Region, Russia

Directory of Open Access Journals (Sweden)

Irina G. Utekhina

2016-04-01

Full Text Available In 2015 one Steller’s Sea Eagle nest was occupied by a Blakiston’s Fish Owl, the first record of which came from the Nature Reserve Inspector, E.A. Stepanov, who, on May 17, noted the pair of fish owls near a Steller’s Sea Eagle nest on the western bank of the Chelomdja River, 3 km downstream from the Moldot ranger’s station. On that date one of the owls was sitting in the nest, and another was sitting in a tree nearby the nest. On May 26, E. Stepanov observed the owls in the same position. We observed the nest on 20 and 21 June 2015, and saw one large Blakiston’s Fish Owl chick in the nest; no adults were noted. Inspector A. Stepanov saw the chick in the nest on June 23, and an adult in a nearby.  Magadan State Reserve Inspector A. Akhanov reported that the nest was empty and no adults were seen on June 25.

Computer Simulations of Composite Electrodes in Solid-Oxide Fuel-Cells

Energy Technology Data Exchange (ETDEWEB)

Sunde, Svein

1999-07-01

Fuel cells are devices for converting the combined chemical (free) energy of fuels and oxygen (air) directly to electrical energy without relying on the dynamic action of steam heated by reacting fuel-oxygen mixtures, like in steam turbines, or of the reacting gas mixtures themselves, like in gas turbines. The basic rationale for fuel cells is their high efficiencies as compared to indirect-conversion methods. Fuel cells are currently being considered for a number of applications, among them de-centralised power supply. Fuel cells come in five basic types and are usually classified according to the type of electrolyte used, which in turn to a significant degree limits the options for anode and cathode materials. The solid-oxide fuel-cell (SOFC) , with which this thesis is concerned, is thus named after its oxide electrolyte, typically the oxide-ion conducting material yttria-stabilised zirconia (YSZ). While the cathode of an SOFC is often uniform in chemical composition (or at least intended to be), various problems of delamination, cracking etc. associated with the use of metallic anode electrocatalysts led to the development of composite SOFC anodes. Porous anodes consisting of Ni and YSZ particles in roughly 50/50 wt-% mixtures are now almost standard with any SOFC-development programme. The designer of composite SOFC electrodes is faced with at least three, interrelated questions: (1) What will be the optimum microstructure and composition of the composite electrode? (2) If the structure changes during operation, as is often observed, what will be the consequences for the internal losses in the cell? (3) How do we interpret electrochemical and conductivity measurements with regard to structure and composition? It is the primary purpose of this thesis to provide a framework for modelling the electrochemical and transport properties of composite electrodes for SOFC, and to arrive at some new insights that cannot be offered by experiment alone. Emphasis is put on

Copper-substituted perovskite compositions for solid oxide fuel cell cathodes and oxygen reduction electrodes in other electrochemical devices

Science.gov (United States)

Rieke, Peter C [Pasco, WA; Coffey, Gregory W [Richland, WA; Pederson, Larry R [Kennewick, WA; Marina, Olga A [Richland, WA; Hardy, John S [Richland, WA; Singh, Prabhaker [Richland, WA; Thomsen, Edwin C [Richland, WA

2010-07-20

The present invention provides novel compositions that find advantageous use in making electrodes for electrochemical cells. Also provided are electrochemical devices that include active oxygen reduction electrodes, such as solid oxide fuel cells, sensors, pumps and the like. The compositions comprises a copper-substituted ferrite perovskite material. The invention also provides novel methods for making and using the electrode compositions and solid oxide fuel cells and solid oxide fuel cell assemblies having cathodes comprising the compositions.

Nest site selection by Kentish plover suggests a trade-off between nest-crypsis and predator detection strategies.

Directory of Open Access Journals (Sweden)

Miguel Ángel Gómez-Serrano

Full Text Available Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of

Strong selection on mandible and nest features in a carpenter bee that nests in two sympatric host plants

OpenAIRE

Flores-Prado, Luis; Pinto, Carlos F; Rojas, Alejandra; Fontúrbel, Francisco E

2014-01-01

Host plants are used by herbivorous insects as feeding or nesting resources. In wood-boring insects, host plants features may impose selective forces leading to phenotypic differentiation on traits related to nest construction. Carpenter bees build their nests in dead stems or dry twigs of shrubs and trees; thus, mandibles are essential for the nesting process, and the nest is required for egg laying and offspring survival. We explored the shape and intensity of natural selection on phenotypi...

Habitat structure and diversity influence the nesting success of an endangered large cavity-nesting bird, the Southern Ground-hornbill

Directory of Open Access Journals (Sweden)

Leigh Combrink

2017-11-01

Full Text Available Habitat features can have a profound effect on the nesting success of birds. Savannas are often managed with predators and large herbivores as priority species, with little thought to the many bird species that management decisions could affect. Using a data set spanning seven breeding seasons, we examined how nesting success of Southern Ground-hornbills (SGHs Bucorvus leadbeateri in the Kruger National Park varied as a result of various environmental and habitat factors within a radius of 3 km surrounding the nest site. Identifying which factors affect nesting success will allow for targeted management efforts to ensure the long-term survival of SGHs both within and outside of protected areas. Habitat structure and diversity of the vegetation surrounding the nest were the most influential factors on SGH nesting success. SGHs require open grassy areas for foraging and areas with large trees for nesting. Savanna habitat drivers such as elephants and fire should be managed to ensure that sufficient large trees are able to establish in the landscape and to control for bush encroachment. This is especially important in areas earmarked for SGH reintroductions. Nest sites of SGHs should be monitored to mitigate any structural changes in the habitat surrounding the nests. Nests should be modified or artificial nest sites provided, where nests have been damaged or lost, to ensure the continued presence of these birds in African savannas. Conservation implications: Habitat structure and diversity surrounding Southern Groundhornbill nests has a significant impact on their nesting success. This highlights the importance of monitoring vegetation change in savanna habitats where they occur. Management of savanna areas should take factors that influence bush encroachment, such as fire and elephants, into account to ensure the long-term persistence of these birds.

Fabrication of cathode supported tubular solid oxide electrolysis cell for high temperature steam electrolysis

Energy Technology Data Exchange (ETDEWEB)

Shao, Le; Wang, Shaorong; Qian, Jiqin; Xue, Yanjie; Liu, Renzhu

2011-01-15

In recent years, hydrogen has been identified as a potential alternative fuel and energy carrier for the future energy supply. Water electrolysis is one of the important hydrogen production technologies which do not emit carbon dioxide. High temperature steam electrolysis (HTSE) consumes even less electrical energy than low temperature water electrolysis. Theoretically, HTSE using solid oxide electrolysis cells (SOEC) can efficiently utilize renewable energy to produce hydrogen, and it is also possible to operate the SOEC in reverse mode as the solid oxide fuel cell (SOFC) to produce electricity. Tubular SOFC have been widely investigated. In this study, tubular solid oxide cells were fabricated by dip-coating and cosintering techniques. In SOEC mode, results suggested that steam ratio had a strong impact on the performance of the tubular cell; the tubular SOEC preferred to be operated at high steam ratio in order to avoid concentration polarization. The microstructure of the tubular SOEC should therefore be optimized for high temperature steam electrolysis.

Three-dimensional ionic conduction in the strained electrolytes of solid oxide fuel cells

International Nuclear Information System (INIS)

Han, Yupei; Zou, Minda; Lv, Weiqiang; He, Weidong; Mao, Yiwu; Wang, Wei

2016-01-01

Flexible power sources including fuel cells and batteries are the key to realizing flexible electronic devices with pronounced foldability. To understand the bending effects in these devices, theoretical analysis on three-dimensional (3-D) lattice bending is necessary. In this report, we derive a 3-D analytical model to analyze the effects of electrolyte crystal bending on ionic conductivity in flexible solid-state batteries/fuel cells. By employing solid oxide fuel cells as a materials' platform, the intrinsic parameters of bent electrolyte materials, including lattice constant, Young's modulus, and Poisson ratio, are evaluated. Our work facilitates the rational design of highly efficient flexible electrolytes for high-performance flexible device applications.

High-temperature, Knudsen cell-mass spectroscopic studies on lanthanum oxide/uranium dioxide solid solutions

International Nuclear Information System (INIS)

Sunder, S.; McEachern, R.; LeBlanc, J.C.

2001-01-01

Knudsen cell-mass spectroscopic experiments were carried out with lanthanum oxide/uranium oxide solid solutions (1%, 2% and 5% (metal at.% basis)) to assess the volatilization characteristics of rare earths present in irradiated nuclear fuel. The oxidation state of each sample used was conditioned to the 'uranium dioxide stage' by heating in the Knudsen cell under an atmosphere of 10% CO 2 in CO. The mass spectra were analyzed to obtain the vapour pressures of the lanthanum and uranium species. It was found that the vapour pressure of lanthanum oxide follows Henry's law, i.e., its value is directly proportional to its concentration in the solid phase. Also, the vapour pressure of lanthanum oxide over the solid solution, after correction for its concentration in the solid phase, is similar to that of uranium dioxide. (authors)

In vivo imaging of cytotoxic T cell infiltration and elimination of a solid tumor.

Science.gov (United States)

Boissonnas, Alexandre; Fetler, Luc; Zeelenberg, Ingrid S; Hugues, Stéphanie; Amigorena, Sebastian

2007-02-19

Although the immune system evolved to fight infections, it may also attack and destroy solid tumors. In most cases, tumor rejection is initiated by CD8(+) cytotoxic T lymphocytes (CTLs), which infiltrate solid tumors, recognize tumor antigens, and kill tumor cells. We use a combination of two-photon intravital microscopy and immunofluorescence on ordered sequential sections to analyze the infiltration and destruction of solid tumors by CTLs. We show that in the periphery of a thymoma growing subcutaneously, activated CTLs migrate with high instantaneous velocities. The CTLs arrest in close contact to tumor cells expressing their cognate antigen. In regions where most tumor cells are dead, CTLs resume migration, sometimes following collagen fibers or blood vessels. CTLs migrating along blood vessels preferentially adopt an elongated morphology. CTLs also infiltrate tumors in depth, but only when the tumor cells express the cognate CTL antigen. In tumors that do not express the cognate antigen, CTL infiltration is restricted to peripheral regions, and lymphocytes neither stop moving nor kill tumor cells. Antigen expression by tumor cells therefore determines both CTL motility within the tumor and profound tumor infiltration.

Influence of flotation cell volume and solids mass on kinetics of sulfide ore flotation

Directory of Open Access Journals (Sweden)

Plawski Michal

2016-01-01

Full Text Available The paper presents studies on the influence of flotation cell capacity and mass of solids in the suspension on the flotation kinetics of sulfide copper ore. A sample of copper ore that was collected from the Polkowice Mine of KGHM Polska Miedz S.A. in Poland was used in the experiments. It was determined that neither the volume of flotation cell nor the mass of solids had influence on the type of kinetics equation of flotation. Copper-bearing minerals floated according to the second-order equation, while the remaining components according to the first-order equation. The kinetic rate constants and maximum recovery of the studied components decreased with increasing solids mass in the flotation cell, regardless of the capacity of the cell. The best results were obtained for tests using a 1.0 dm3 cell, while the less favorable kinetics results were observed in the test with the smallest cell of 0.75 dm3 volume. The obtained results can be helpful in choosing the most appropriate methodology of upgrading the sulfide copper ore from Poland in order to obtain the best kinetics results.

Repeatability of nest morphology in African weaver birds.

Science.gov (United States)

Walsh, Patrick T; Hansell, Mike; Borello, Wendy D; Healy, Susan D

2010-04-23

It is generally assumed that birds build nests according to a genetic 'template', little influenced by learning or memory. One way to confirm the role of genetics in nest building is to assess the repeatability of nest morphology with repeated nest attempts. Solitary weaver birds, which build multiple nests in a single breeding season, are a useful group with which to do this. Here we show that repeatability of nest morphology was low, but significant, in male Southern Masked weaver birds and not significant in the Village weavers. The larger bodied Village weavers built larger nests than did Southern Masked weavers, but body size did not explain variation in Southern Masked weaver nest dimensions. Nests built by the same male in both species got shorter and lighter as more nests were constructed. While these data demonstrate the potential for a genetic component of variation in nest building in solitary weavers, it is also clear that there remains plenty of scope in both of these species for experience to shape nest construction.

Nest Construction by a Ground-nesting Bird Represents a Potential Trade-off Between Egg Crypticity and Thermoregulation

Science.gov (United States)

Predation selects against conspicuous colors in bird eggs and nests, while thermoregulatory constraints select for nest building behavior that regulates incubation temperatures. We present results that reveal a trade-off between nest crypticity and thermoregulation of eggs base...

Generator module architecture for a large solid oxide fuel cell power plant

Science.gov (United States)

Gillett, James E.; Zafred, Paolo R.; Riggle, Matthew W.; Litzinger, Kevin P.

2013-06-11

A solid oxide fuel cell module contains a plurality of integral bundle assemblies, the module containing a top portion with an inlet fuel plenum and a bottom portion receiving air inlet feed and containing a base support, the base supports dense, ceramic exhaust manifolds which are below and connect to air feed tubes located in a recuperator zone, the air feed tubes passing into the center of inverted, tubular, elongated, hollow electrically connected solid oxide fuel cells having an open end above a combustion zone into which the air feed tubes pass and a closed end near the inlet fuel plenum, where the fuel cells comprise a fuel cell stack bundle all surrounded within an outer module enclosure having top power leads to provide electrical output from the stack bundle, where the fuel cells operate in the fuel cell mode and where the base support and bottom ceramic air exhaust manifolds carry from 85% to all 100% of the weight of the stack, and each bundle assembly has its own control for vertical and horizontal thermal expansion control.

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: New Hampshire: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for nesting birds in New Hampshire. Vector points in this data set represent locations of nesting osprey...

Application of the monolithic solid oxide fuel cell to space power systems

International Nuclear Information System (INIS)

Myles, K.M.; Bhattacharyya, S.K.

1991-01-01

The monolithic solid-oxide fuel cell (MSOFC) is a promising electrochemical power generation device that is currently under development at Argonne National Laboratory. The extremely high power density of the MSOFC leads to MSOFC systems that have sufficiently high energy densities that they are excellent candidates for a number of space missions. The fuel cell can also be operated in reverse, if it can be coupled to an external power source, to regenerate the fuel and oxidant from the water product. This feature further enhances the potential mission applications of the MSOFC. In this paper, the current status of the fuel cell development is presented---the focus being on fabrication and currently achievable performance. In addition, a specific example of a space power system, featuring a liquid metal cooled fast spectrum nuclear reactor and a monolithic solid oxide fuel cell, is presented to demonstrate the features of an integrated system

Application of the monolithic solid oxide fuel cell to space power systems

Science.gov (United States)

Myles, Kevin M.; Bhattacharyya, Samit K.

1991-01-01

The monolithic solid-oxide fuel cell (MSOFC) is a promising electrochemical power generation device that is currently under development at Argonne National Laboratory. The extremely high power density of the MSOFC leads to MSOFC systems that have sufficiently high energy densities that they are excellent candidates for a number of space missions. The fuel cell can also be operated in reverse, if it can be coupled to an external power source, to regenerate the fuel and oxidant from the water product. This feature further enhances the potential mission applications of the MSOFC. In this paper, the current status of the fuel cell development is presented—the focus being on fabrication and currently achievable performance. In addition, a specific example of a space power system, featuring a liquid metal cooled fast spectrum nuclear reactor and a monolithic solid oxide fuel cell, is presented to demonstrate the features of an integrated system.

TAPE CALENDERING MANUFACTURING PROCESS FOR MULTILAYER THIN-FILM SOLID OXIDE FUEL CELLS

Energy Technology Data Exchange (ETDEWEB)

Nguyen Minh; Kurt Montgomery

2004-10-01

This report summarizes the work performed by Hybrid Power Generation Systems, LLC during the Phases I and II under Contract DE-AC26-00NT40705 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Tape Calendering Manufacturing Process For Multilayer Thin-Film Solid Oxide Fuel Cells''. The main objective of this project was to develop the manufacturing process based on tape calendering for multilayer solid oxide fuel cells (SOFC's) using the unitized cell design concept and to demonstrate cell performance under specified operating conditions. Summarized in this report is the development and improvements to multilayer SOFC cells and the unitized cell design. Improvements to the multilayer SOFC cell were made in electrochemical performance, in both the anode and cathode, with cells demonstrating power densities of nearly 0.9 W/cm{sup 2} for 650 C operation and other cell configurations showing greater than 1.0 W/cm{sup 2} at 75% fuel utilization and 800 C. The unitized cell design was matured through design, analysis and development testing to a point that cell operation at greater than 70% fuel utilization was demonstrated at 800 C. The manufacturing process for both the multilayer cell and unitized cell design were assessed and refined, process maps were developed, forming approaches explored, and nondestructive evaluation (NDE) techniques examined.

Aspectos da biologia de nidificação de Euplusia mussitans (Fabricius (Hymenoptera, Apidae, Euglossini Aspects of nesting biology of Euplusia mussitans Fabricius (Hymenoptera, Apidae, Euglossini

Directory of Open Access Journals (Sweden)

Blandina Felipe Viana

2001-12-01

Full Text Available The architecture and biology of Euplusia mussitans (Fabricius, 1787 nests were investigated, using trap nests made by wood, which were randomly distributed in a fragment of a coastal sand dunes, in Salvador, Bahia. Brazil (12º56'S and 38º21'W. 10 nests were found in cavities with 1.5 cm in diameter. From them emerged 10 females and 16 males (Sex ratio = 0,38. The nest cells were made of small pieces of bark cemented together with resin. The number of cells in the nests varied from 2 to 4, with females cells at the inner end and males cells towards the entrance. No significant difference was observed (t= 0.7274, P > 0.05 between the medium size for males (6.3 mm ± 0.16 and for females (6.4 mm ± 0.29. The development time of females was longer than males.

Analytical investigation on cell temperature control method of planar solid oxide fuel cell

Energy Technology Data Exchange (ETDEWEB)

Inui, Y.; Ito, N.; Nakajima, T.; Urata, A. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi (Japan)

2006-09-15

The solid oxide fuel cell (SOFC) has a problem in durability of the ceramics used as its cell materials because its operating temperature is very high and the cell temperature fluctuation induces thermal stress in the ceramics. The cell temperature distribution in the SOFC, therefore, should be kept as constant as possible during variable load operation through control of the average current density in the cell. Considering this fact, the authors numerically optimize the operating parameters of air utilization and the inlet gas temperature of the planar SOFC by minimizing the cell temperature shift from its nominal value and propose a new cell temperature control method that adopts these optimum operating parameters for each average current density. The effectiveness of the proposed method is very high and the temperature variation is suppressed to a very low level without lowering the single cell voltage for both the co-flow and counter-flow type cells, indicating that the proposed cell temperature control method makes variable load operation of the planar SOFC possible. (author)

Nest trampling and ground nesting birds: Quantifying temporal and spatial overlap between cattle activity and breeding redshank.

Science.gov (United States)

Sharps, Elwyn; Smart, Jennifer; Mason, Lucy R; Jones, Kate; Skov, Martin W; Garbutt, Angus; Hiddink, Jan G

2017-08-01

Conservation grazing for breeding birds needs to balance the positive effects on vegetation structure and negative effects of nest trampling. In the UK, populations of Common redshank Tringa totanus breeding on saltmarshes declined by >50% between 1985 and 2011. These declines have been linked to changes in grazing management. The highest breeding densities of redshank on saltmarshes are found in lightly grazed areas. Conservation initiatives have encouraged low-intensity grazing at nest trampling. If livestock distribution is not spatially or temporally homogenous but concentrated where and when redshank breed, rates of nest trampling may be much higher than expected based on livestock density alone. By GPS tracking cattle on saltmarshes and monitoring trampling of dummy nests, this study quantified (i) the spatial and temporal distribution of cattle in relation to the distribution of redshank nesting habitats and (ii) trampling rates of dummy nests. The distribution of livestock was highly variable depending on both time in the season and the saltmarsh under study, with cattle using between 3% and 42% of the saltmarsh extent and spending most their time on higher elevation habitat within 500 m of the sea wall, but moving further onto the saltmarsh as the season progressed. Breeding redshank also nest on these higher elevation zones, and this breeding coincides with the early period of grazing. Probability of nest trampling was correlated to livestock density and was up to six times higher in the areas where redshank breed. This overlap in both space and time of the habitat use of cattle and redshank means that the trampling probability of a nest can be much higher than would be expected based on standard measures of cattle density. Synthesis and applications : Because saltmarsh grazing is required to maintain a favorable vegetation structure for redshank breeding, grazing management should aim to keep livestock away from redshank nesting habitat between mid

The design and function of birds' nests

Science.gov (United States)

Mainwaring, Mark C; Hartley, Ian R; Lambrechts, Marcel M; Deeming, D Charles

2014-01-01

All birds construct nests in which to lay eggs and/or raise offspring. Traditionally, it was thought that natural selection and the requirement to minimize the risk of predation determined the design of completed nests. However, it is becoming increasingly apparent that sexual selection also influences nest design. This is an important development as while species such as bowerbirds build structures that are extended phenotypic signals whose sole purpose is to attract a mate, nests contain eggs and/or offspring, thereby suggesting a direct trade-off between the conflicting requirements of natural and sexual selection. Nest design also varies adaptively in order to both minimize the detrimental effects of parasites and to create a suitable microclimate for parents and developing offspring in relation to predictable variation in environmental conditions. Our understanding of the design and function of birds' nests has increased considerably in recent years, and the evidence suggests that nests have four nonmutually exclusive functions. Consequently, we conclude that the design of birds' nests is far more sophisticated than previously realized and that nests are multifunctional structures that have important fitness consequences for the builder/s. PMID:25505520

The design and function of birds' nests.

Science.gov (United States)

Mainwaring, Mark C; Hartley, Ian R; Lambrechts, Marcel M; Deeming, D Charles

2014-10-01

All birds construct nests in which to lay eggs and/or raise offspring. Traditionally, it was thought that natural selection and the requirement to minimize the risk of predation determined the design of completed nests. However, it is becoming increasingly apparent that sexual selection also influences nest design. This is an important development as while species such as bowerbirds build structures that are extended phenotypic signals whose sole purpose is to attract a mate, nests contain eggs and/or offspring, thereby suggesting a direct trade-off between the conflicting requirements of natural and sexual selection. Nest design also varies adaptively in order to both minimize the detrimental effects of parasites and to create a suitable microclimate for parents and developing offspring in relation to predictable variation in environmental conditions. Our understanding of the design and function of birds' nests has increased considerably in recent years, and the evidence suggests that nests have four nonmutually exclusive functions. Consequently, we conclude that the design of birds' nests is far more sophisticated than previously realized and that nests are multifunctional structures that have important fitness consequences for the builder/s.

Biomass-powered Solid Oxide Fuel Cells : Experimental and Modeling Studies for System Integrations

NARCIS (Netherlands)

Liu, M.

2013-01-01

Biomass is a sustainable energy source which, through thermo-chemical processes of biomass gasification, is able to be converted from a solid biomass fuel into a gas mixture, known as syngas or biosyngas. A solid oxide fuel cell (SOFC) is a power generation device that directly converts the chemical

Non-destructive delamination detection in solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Gazzarri, J.I.; Kesler, O. [Department of Mechanical Engineering, University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, BC V6T 1Z4 (Canada)

2007-05-15

A finite element model has been developed to simulate the steady state and impedance behaviour of a single operating solid oxide fuel cell (SOFC). The model results suggest that electrode delamination can be detected minimally-invasively by using electrochemical impedance spectroscopy. The presence of cathode delamination causes changes in the cell impedance spectrum that are characteristic of this type of degradation mechanism. These changes include the simultaneous increase in both the series and polarization resistances, in proportion to the delaminated area. Parametric studies show the dependence of these changes on the extent of delamination, on the operating point, and on the kinetic characteristics of the fuel cell under study. (author)

Three-phase boundary length in solid-oxide fuel cells: A mathematical model

Energy Technology Data Exchange (ETDEWEB)

Janardhanan, Vinod M. [Institutefor Chemical Technology and Polymer Chemistry, University of Karlsruhe (TH), Kaiserstr. 12, D-76128 Karlsruhe (Germany); Heuveline, Vincent; Deutschmann, Olaf [Institute for Applied and Numerical Mathematics, University of Karlsruhe (TH), Kaiserstr. 12, D-76128 Karlsruhe (Germany)

2008-03-15

A mathematical model to calculate the volume specific three-phase boundary length in the porous composite electrodes of solid-oxide fuel cell is presented. The model is exclusively based on geometrical considerations accounting for porosity, particle diameter, particle size distribution, and solids phase distribution. Results are presented for uniform particle size distribution as well as for non-uniform particle size distribution. (author)

Three-phase boundary length in solid-oxide fuel cells: A mathematical model

Science.gov (United States)

Janardhanan, Vinod M.; Heuveline, Vincent; Deutschmann, Olaf

A mathematical model to calculate the volume specific three-phase boundary length in the porous composite electrodes of solid-oxide fuel cell is presented. The model is exclusively based on geometrical considerations accounting for porosity, particle diameter, particle size distribution, and solids phase distribution. Results are presented for uniform particle size distribution as well as for non-uniform particle size distribution.

The study of flow and proton exchange interactions in the cylindrical solid oxide fuel cell

International Nuclear Information System (INIS)

Saievar-Iranizad, E.; Malekifar, A.

2002-01-01

The solid oxide fuel cell operates at high temperature of about 1000 deg C. In this temperature, some known materials such as Ni, ... which is abundant in the nature, can be used as a catalyst in the electrodes. The electrolytes of such cell solid oxide fuel cell can be made through non-porous solid ceramics such as Zircon's (ZrO 2 ). It can be stabilized using a doped Yttrium oxide. The importance of Yttria-stabilised Zirconia at high temperature belongs to the transport of oxygen ions through the electrolyte. Oxygen using in the hot cathode side causes a considerable reduction in the concentration of oxygen molecules. The oxygen ions exchange through the electrolyte relates to the molecular oxygen concentration gradient between the anode and cathode. Applying fuels such as hydrogen or natural gas in the anode and its chemical reaction with oxygen ions transfer from cathode through the electrolyte, produce electricity, water and heat. To study the ion exchange and its interaction into solid oxide fuel cell, a mathematical model had been considered in this article. This model simulates and illustrates the interaction, diffusion and oxygen ions exchange into fuel cell. The electrical power of fuel cell due to the ion exchange can be obtained using a simulation method. The ion exchange simulation, diffusion of molecules, their interactions and system development through the mathematical model has been discussed in this paper

Electrochemical Synthesis of Ammonia in Solid Electrolyte Cells

Energy Technology Data Exchange (ETDEWEB)

Garagounis, Ioannis; Kyriakou, Vasileios [Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki (Greece); Chemical Processes and Energy Resources Institute, Center for Research and Technology Hellas, Thessaloniki (Greece); Skodra, Aglaia [Chemical Processes and Energy Resources Institute, Center for Research and Technology Hellas, Thessaloniki (Greece); Vasileiou, Eirini; Stoukides, Michael, E-mail: stoukidi@cperi.certh.gr [Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki (Greece); Chemical Processes and Energy Resources Institute, Center for Research and Technology Hellas, Thessaloniki (Greece)

2014-01-17

Developed in the early 1900s, the “Haber–Bosch” synthesis is the dominant NH{sub 3} synthesis process. Parallel to catalyst optimization, current research efforts are also focused on the investigation of new methods for ammonia synthesis, including the electrochemical synthesis with the use of solid electrolyte cells. Since the first report on Solid State Ammonia Synthesis (SSAS), more than 30 solid electrolyte materials were tested and at least 15 catalysts were used as working electrodes. Thus far, the highest rate of ammonia formation reported is 1.13 × 10{sup -8} mol s{sup -1} cm{sup -2}, obtained at 80°C with a Nafion solid electrolyte and a mixed oxide, SmFe{sub 0.7}Cu{sub 0.1}Ni{sub 0.2}O{sub 3}, cathode. At high temperatures (>500°C), the maximum rate was 9.5 × 10{sup −9} mol s{sup -1} cm{sup -2} using Ce{sub 0.8}Y{sub 0.2}O{sub 2-δ}–[Ca{sub 3}(PO{sub 4}){sub 2}–K{sub 3}PO{sub 4}] as electrolyte and Ag–Pd as cathode. In this paper, the advantages and the disadvantages of SSAS vs. the conventional process and the requirements that must be met in order to promote the electrochemical process into an industrial level are discussed.

Study of solid and liquid behavior in large copper flotation cells (130 m2) using radioactive tracers

International Nuclear Information System (INIS)

Diaz, F.; Jimenez, O.; Yianatos, J.; Contreras, F.

2013-01-01

The behavior of the solid and liquid phases, in large flotation cells, was characterized by means of the radioactive tracer technique. The use of radioactive tracers enabled the identification of the Residence Time Distribution, of floatable and non-floatable solid, from continuous (on-line) measuring at the output streams of the flotation cells. For this study, the proper radioactive tracers were selected and applied in order to characterize the different phases; i.e. for liquid phase Br-82 as Ammonium Bromide, for floatable solid recovered in the concentrate Cu-64, and for non-floatable solid in three particle size classes (coarse: >150 μm, intermediate: 45 μm, and fine: <45 μm), Na-24. The experimental results confirmed the strong effect of particle size on the Residence Time Distribution, and mean residence time of solids in larger flotation cells, and consequently in flotation hydrodynamics. From a hydrodynamic point of view, the experimental data confirmed that a single mechanical flotation cells, of large size, can deviate significantly from perfect mixing. The experimental work was developed in a 130 m3 industrial flotation cell of the rougher circuit at El Teniente Division, Codelco-Chile. (authors)

Estimating raptor nesting success: old and new approaches

Science.gov (United States)

Brown, Jessi L.; Steenhof, Karen; Kochert, Michael N.; Bond, Laura

2013-01-01

Studies of nesting success can be valuable in assessing the status of raptor populations, but differing monitoring protocols can present unique challenges when comparing populations of different species across time or geographic areas. We used large datasets from long-term studies of 3 raptor species to compare estimates of apparent nest success (ANS, the ratio of successful to total number of nesting attempts), Mayfield nesting success, and the logistic-exposure model of nest survival. Golden eagles (Aquila chrysaetos), prairie falcons (Falco mexicanus), and American kestrels (F. sparverius) differ in their breeding biology and the methods often used to monitor their reproduction. Mayfield and logistic-exposure models generated similar estimates of nesting success with similar levels of precision. Apparent nest success overestimated nesting success and was particularly sensitive to inclusion of nesting attempts discovered late in the nesting season. Thus, the ANS estimator is inappropriate when exact point estimates are required, especially when most raptor pairs cannot be located before or soon after laying eggs. However, ANS may be sufficient to assess long-term trends of species in which nesting attempts are highly detectable.

Complementary techniques for solid oxide cell characterisation on micro- and nano-scale

International Nuclear Information System (INIS)

Wiedenmann, D.; Hauch, A.; Grobety, B.; Mogensen, M.; Vogt, U.

2009-01-01

High temperature steam electrolysis by solid oxide electrolysis cells (SOEC) is a way with great potential to transform clean and renewable energy from non-fossil sources to synthetic fuels such as hydrogen, methane or dimethyl ether, which have been identified as promising alternative energy carriers. Also, as SOEC can operate in the reverse mode as solid oxide fuel cells (SOFC), during high peak hours e.g. hydrogen can be used in a very efficient way to reconvert chemically stored energy into electrical energy. As solid oxide cells (SOC) are working at high temperatures (700-900 o C), material degradation and evaporation can occur e.g. from the cell sealing material, leading to poisoning effects and aging mechanisms which are decreasing the cell efficiency and long-term durability. In order to investigate such cell degradation processes, thorough examination on SOC often requires the chemical and structural characterisation on the microscopic and the nanoscopic level. The combination of different microscope techniques like conventional scanning electron microscopy (SEM), electron-probe microanalysis (EPMA) and the focused ion-beam (FIB) preparation technique for transmission electron microscopy (TEM) allows performing post mortem analysis on a multi scale level of cells after testing. These complementary techniques can be used to characterize structural and chemical changes over a large and representative sample area (micro-scale) on the one hand, and also on the nano-scale level for selected sample details on the other hand. This article presents a methodical approach for the structural and chemical characterisation of changes in aged cathode-supported electrolysis cells produced at Riso DTU, Denmark. Also, results from the characterisation of impurities at the electrolyte/hydrogen interface caused by evaporation from sealing material are discussed. (author)

Reviews on Solid Oxide Fuel Cell Technology

Directory of Open Access Journals (Sweden)

Apinan Soottitantawat

2009-02-01

Full Text Available Solid Oxide Fuel Cell (SOFC is one type of high temperature fuel cell that appears to be one of the most promising technology to provide the efficient and clean energy production for wide range of applications (from small units to large scale power plants. This paper reviews the current status and related researches on SOFC technologies. In details, the research trend for the development of SOFC components(i.e. anode, electrolyte, cathode, and interconnect are presented. Later, the current important designs of SOFC (i.e. Seal-less Tubular Design, Segmented Cell in Series Design, Monolithic Design and Flat Plate Design are exampled. In addition, the possible operations of SOFC (i.e. external reforming, indirect internal reforming, and direct internal reforming are discussed. Lastly, the research studies on applications of SOFCs with co-generation (i.e. SOFC with Combined Heat and Power (SOFC-CHP, SOFC with Gas Turbine (SOFC-GT and SOFC with chemical production are given.

An afterburner-powered methane/steam reformer for a solid oxide fuel cells application

Science.gov (United States)

Mozdzierz, Marcin; Chalusiak, Maciej; Kimijima, Shinji; Szmyd, Janusz S.; Brus, Grzegorz

2018-04-01

Solid oxide fuel cell (SOFC) systems can be fueled by natural gas when the reforming reaction is conducted in a stack. Due to its maturity and safety, indirect internal reforming is usually used. A strong endothermic methane/steam reforming process needs a large amount of heat, and it is convenient to provide thermal energy by burning the remainders of fuel from a cell. In this work, the mathematical model of afterburner-powered methane/steam reformer is proposed. To analyze the effect of a fuel composition on SOFC performance, the zero-dimensional model of a fuel cell connected with a reformer is formulated. It is shown that the highest efficiency of a solid oxide fuel cell is achieved when the steam-to-methane ratio at the reforming reactor inlet is high.

Curvature and Strength of Ni-YSZ Solid Oxide Half-Cells After Redox Treatments

DEFF Research Database (Denmark)

Faes, Antonin; Frandsen, Henrik Lund; Pihlatie, Mikko

2010-01-01

One of the main drawbacks of anode-supported solid oxide fuel cell technology is the limited capability to withstand reduction and oxidation (“RedOx”) of the Ni phase. This study compares the effect of RedOx cycles on curvature and strength of half-cells, composed of a nickel-yttria-stabilized-zi......One of the main drawbacks of anode-supported solid oxide fuel cell technology is the limited capability to withstand reduction and oxidation (“RedOx”) of the Ni phase. This study compares the effect of RedOx cycles on curvature and strength of half-cells, composed of a nickel...... it is calculated analytically from the force. In this calculation the thermal stresses are estimated from the curvature of the half-cell. For each treatment, more than 30 samples are tested. About 20 ball-on-ring samples are laser cut from one original 12×12 cm2 half-cell. Curvature and porosity are measured...

Response of beach-nesting American Oystercatchers to off-road vehicles: An experimental approach reveals physiological nuances and decreased nest attendance

Science.gov (United States)

Felton, Shilo K.; Pollock, Kenneth H.; Simons, Theodore R.

2018-01-01

Shorebird populations face increasing challenges as rising sea levels and growing human populations constrain their breeding habitats. On recreational beaches, the nesting season often coincides with a season of high visitor use, increasing the potential for conflict, which may negatively influence beach-nesting shorebird species. We designed a field experiment to study the responses of nesting American Oystercatchers (Haematopus palliatus) to off-road passenger vehicles (ORVs) at Cape Hatteras and Cape Lookout National Seashores in North Carolina, USA. We used continuous video and heart rate recordings to assess changes in the behavior and physiology of incubating oystercatchers. We conducted driving experiments affecting 7 nesting pairs in 2014 and 19 nesting pairs in 2015, between April and July of each year. Experimental treatments were repeated throughout the incubation period for each nest. Although responses were highly variable within and among pairs, paired randomized permutation tests indicated that, overall, oystercatcher pairs spent a greater proportion of time with their heads up and exhibited slower heart rates during driving treatments. Pairs also left their nests more frequently and attended their nests for a lower proportion of time during driving treatments, although these responses diminished over time. Higher nest attendance and lower departure rates late in incubation may have reflected a stronger attachment to nests closer to hatching or habituation to the driving treatment, although individuals continued to exhibit physiological responses to passing vehicles throughout incubation. Beach-nesting birds may benefit from reduced vehicle traffic at their nesting sites, allowing parents to spend more time attending the nest and less time on defensive behaviors.

Advanced impedance modeling of solid oxide electrochemical cells

DEFF Research Database (Denmark)

Graves, Christopher R.; Hjelm, Johan

2014-01-01

Impedance spectroscopy is a powerful technique for detailed study of the electrochemical and transport processes that take place in fuel cells and electrolysis cells, including solid oxide cells (SOCs). Meaningful analysis of impedance measurements is nontrivial, however, because a large number...... techniques to provide good guesses for the modeling parameters, like transforming the impedance data to the distribution of relaxation times (DRT), together with experimental parameter sensitivity studies, is the state-of-the-art approach to achieve good EC model fits. Here we present new impedance modeling...... electrode and 2-D gas transport models which have fewer unknown parameters for the same number of processes, (ii) use of a new model fitting algorithm, “multi-fitting”, in which multiple impedance spectra are fit simultaneously with parameters linked based on the variation of measurement conditions, (iii...

EFL Students' and Teachers' Attitudes toward Foreign Language Speaking Anxiety: A Look at NESTs and Non-NESTs

Science.gov (United States)

Han, Turgay; Tanriöver, Ahmet Serkan; Sahan, Özgür

2016-01-01

Native English Speaking Teachers (NESTs) have been employed in various English language teaching (ELT) positions and departments at private and state universities in Turkey, particularly over the last three decades. However, undergraduate EFL students' attitudes toward NESTs and Non-Native English Speaking Teachers (Non-NESTs) remain seriously…

Copper accumulation by stickleback nests containing spiggin.

Science.gov (United States)

Pinho, G L L; Martins, C M G; Barber, I

2016-07-01

The three-spined stickleback is a ubiquitous fish of marine, brackish and freshwater ecosystems across the Northern hemisphere that presents intermediate sensitivity to copper. Male sticklebacks display a range of elaborate reproductive behaviours that include nest construction. To build the nests, each male binds nesting material together using an endogenous glycoprotein nesting glue, known as 'spiggin'. Spiggin is a cysteine-rich protein and, therefore, potentially binds heavy metals present in the environment. The aim of this study was to investigate the capacity of stickleback nests to accumulate copper from environmental sources. Newly built nests, constructed by male fish from polyester threads in laboratory aquaria, were immersed in copper solutions ranging in concentration from 21.1-626.6 μg Cu L(-1). Bundles of polyester threads from aquaria without male fish were also immersed in the same copper solutions. After immersion, nests presented higher amounts of copper than the thread bundles, indicating a higher capacity of nests to bind this metal. A significant, positive correlation between the concentration of copper in the exposure solution and in the exposed nests was identified, but there was no such relationship for thread bundles. Since both spiggin synthesis and male courtship behaviour are under the control of circulating androgens, we predicted that males with high courtship scores would produce and secrete high levels of the spiggin protein. In the present study, nests built by high courtship score males accumulated more copper than those built by low courtship score males. Considering the potential of spiggin to bind metals, the positive relationship between fish courtship and spiggin secretion seems to explain the higher amount of copper on the nests from the fish showing high behaviour scores. Further work is now needed to determine the consequences of the copper binding potential of spiggin in stickleback nests for the health and survival of

Spectroelectrochemical cell for in situ studies of solid oxide fuel cells

DEFF Research Database (Denmark)

Hagen, Anke; Traulsen, Marie Lund; Kiebach, Wolff-Ragnar

2012-01-01

to control before the technology can achieve breakthrough. They have been widely studied, predominately by electrochemical testing with subsequent micro-structural analysis. In order to be able to develop better SOFCs, it is important to understand how the measured electrochemical performance depends......Solid oxide fuel cells (SOFCs) are able to produce electricity and heat from hydrogen- or carbon-containing fuels with high efficiencies and are considered important cornerstones for future sustainable energy systems. Performance, activation and degradation processes are crucial parameters...... on materials and structural properties, preferably at the atomic level. A characterization of these properties under operation is desired. As SOFCs operate at temperatures around 1073 K, this is a challenge. A spectroelectrochemical cell was designed that is able to study SOFCs at operating temperatures...

PREPARATION AND CHARACTERIZATION OF SOLID ELECTROLYTES: FUEL CELL APPLICATIONS

Energy Technology Data Exchange (ETDEWEB)

Rambabu Bobba; Josef Hormes; T. Wang; Jaymes A. Baker; Donald G. Prier; Tommy Rockwood; Dinesha Hawkins; Saleem Hasan; V. Rayanki

1997-12-31

The intent of this project with Federal Energy Technology Center (FETC)/Morgantown Energy Technology Center (METC) is to develop research infrastructure conductive to Fuel Cell research at Southern University and A and M College, Baton Route. A state of the art research laboratory (James Hall No.123 and No.114) for energy conversion and storage devices was developed during this project duration. The Solid State Ionics laboratory is now fully equipped with materials research instruments: Arbin Battery Cycling and testing (8 channel) unit, Electrochemical Analyzer (EG and G PAR Model 273 and Solartron AC impedance analyzer), Fuel Cell test station (Globe Tech), Differential Scanning Calorimeter (DSC-10), Thermogravimetric Analyzer (TGA), Scanning Tunneling Microscope (STM), UV-VIS-NIR Absorption Spectrometer, Fluorescence Spectrometer, FT-IR Spectrometer, Extended X-ray Absorption Fine Structure (EXAFS) measurement capability at Center for Advanced Microstructure and Devices (CAMD- a multimillion dollar DOE facility), Glove Box, gas hood chamber, high temperature furnaces, hydraulic press and several high performance computers. IN particular, a high temperature furnace (Thermodyne 6000 furnace) and a high temperature oven were acquired through this project funds. The PI Dr. R Bobba has acquired additional funds from federal agencies include NSF-Academic Research Infrastructure program and other DOE sites. They have extensively used the multimillion dollar DOE facility ''Center'' for Advanced Microstructures and Devices (CAMD) for electrochemical research. The students were heavily involved in the experimental EXAFS measurements and made use of their DCM beamline for EXAFS research. The primary objective was to provide hands on experience to the selected African American undergraduate and graduate students in experimental energy research.The goal was to develop research skills and involve them in the Preparation and Characterization of Solid

Construction patterns of birds' nests provide insight into nest-building behaviours

OpenAIRE

Biddle, Lucia; Goodman, Adrian; Deeming, Charles

2017-01-01

Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in a...

The TMI Regenerative Solid Oxide Fuel Cell

Science.gov (United States)

Cable, Thomas L.; Ruhl, Robert C.; Petrik, Michael

1996-01-01

Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. Systems generally consist of photovoltaic solar arrays which operate (during sunlight cycles) to provide system power and regenerate fuel (hydrogen) via water electrolysis and (during dark cycles) fuel cells convert hydrogen into electricity. Common configurations use two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Reliability, power to weight and power to volume ratios could be greatly improved if both power production (fuel cells) and power storage (electrolysis) functions can be integrated into a single unit. The solid oxide fuel cell (SOFC) based design integrates fuel cell and electrolyzer functions and potentially simplifies system requirements. The integrated fuel cell/electrolyzer design also utilizes innovative gas storage concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H20 electrode (SOFC anode/electrolyzer cathode) materials for regenerative fuel cells. Tests have shown improved cell performance in both fuel and electrolysis modes in reversible fuel cell tests. Regenerative fuel cell efficiencies, ratio of power out (fuel cell mode) to power in (electrolyzer mode), improved from 50 percent using conventional electrode materials to over 80 percent. The new materials will allow a single SOFC system to operate as both the electolyzer and fuel cell. Preliminary system designs have also been developed to show the technical feasibility of using the design for space applications requiring high energy storage efficiencies and high specific energy. Small space systems also have potential for dual-use, terrestrial applications.

Constructing bald eagle nests with natural materials

Science.gov (United States)

T. G. Grubb

1995-01-01

A technique for using natural materials to build artificial nests for bald eagles (Haliaeetus leucocephalus) and other raptors is detailed. Properly constructed nests are as permanently secured to the nest tree or cliff substrate as any eagle-built nest or human-made platform. Construction normally requires about three hours and at least two people. This technique is...

Solid oxide fuel cell field trial evaluation

Energy Technology Data Exchange (ETDEWEB)

Wilcox, C.P.; Winstanley, R.; Nietsch, T.; Smith, C.; Knight, R.; Seymore, C.

2000-07-01

This report focuses on issues relating to a field trial of a solid oxide fuel cell (SOFC). Aspects examined include markets for SOFC systems, the choice of systems for demonstration in year 2002, the assessment of industrial interest, and evaluation and ranking of candidate systems. The identification and evaluation of interest in field trials, the estimation of the capital and running costs of a field trial, and identification of the benefits to the UK and barriers to implementation of SOFC systems are discussed. (UK)

Light pollution affects nesting behavior of loggerhead turtles and predation risk of nests and hatchlings.

Science.gov (United States)

Silva, Elton; Marco, Adolfo; da Graça, Jesemine; Pérez, Héctor; Abella, Elena; Patino-Martinez, Juan; Martins, Samir; Almeida, Corrine

2017-08-01

The introduction of artificial light into wildlife habitats is a rapidly expanding aspect of global change, which has many negative impacts on a wide range of taxa. In this experimental study, which took place on a beach located on the island of Boa Vista (Cabo Verde), three types of artificial light were tested on nesting loggerhead sea turtles as well as on ghost crabs, which intensively predate on nests and hatchlings, to determine the effects they would produce on the behavior of both species. Over the course of 36days, female loggerheads and ghost crabs were studied under yellow, orange and red lights, with observations also being made on dark nights that served as a control treatment. During this period, the frequencies of nesting attempts, the time taken by turtles to complete each phase of the nesting process, and ghost crab abundance and behaviors were carefully recorded. 1146 loggerhead nesting attempts were observed and recorded during the experiments, and results showed a decrease in nesting attempts of at least 20% when artificial lighting was present. A significant decline in successful attempts was also observed within the central sections of the beach, which corresponded to those that received more light. This artificial lighting significantly increased the time that turtles spent on the nesting process and forced them to do more extensive beach crawls. Despite this, the presence of light had no apparent effect on the final selection of the nesting site. Yellow and orange lights significantly disrupted the sea finding behavior and turtles were often unable to orient themselves seaward under these color lights. Disoriented turtles were observed crawling in circuitous paths in front of the light source for several minutes. In addition, artificial lights had the potential to increase the number of ghost crabs present within the illuminated stretches of the beach. However, only yellow lighting produced a significant change on aggressive and prey

Bristol Bay, Alaska Subarea ESI: NESTS (Nest Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for nesting seabirds (alcids, pelagic birds), gulls, terns, diving birds, and raptors in the Bristol Bay...

Novel quasi-symmetric solid oxide fuel cells with enhanced electrochemical performance

KAUST Repository

Chen, Yonghong; Cheng, Zhuanxia; Yang, Yang; Gu, Qingwen; Tian, Dong; Lu, Xiaoyong; Yu, Weili; Lin, Bin

2016-01-01

Symmetrical solid oxide fuel cell (SSOFC) using same materials as both anode and cathode simultaneously has gained extensively attentions, which can simplify fabrication process, minimize inter-diffusion between components, enhance sulfur and coking

Strong selection on mandible and nest features in a carpenter bee that nests in two sympatric host plants.

Science.gov (United States)

Flores-Prado, Luis; Pinto, Carlos F; Rojas, Alejandra; Fontúrbel, Francisco E

2014-05-01

Host plants are used by herbivorous insects as feeding or nesting resources. In wood-boring insects, host plants features may impose selective forces leading to phenotypic differentiation on traits related to nest construction. Carpenter bees build their nests in dead stems or dry twigs of shrubs and trees; thus, mandibles are essential for the nesting process, and the nest is required for egg laying and offspring survival. We explored the shape and intensity of natural selection on phenotypic variation on three size measures of the bees (intertegular width, wing length, and mandible area) and two nest architecture measures (tunnel length and diameter) on bees using the native species Chusquea quila (Poaceae), and the alloctonous species Rubus ulmifolius (Rosaceae), in central Chile. Our results showed significant and positive linear selection gradients for tunnel length on both hosts, indicating that bees building long nests have more offspring. Bees with broader mandibles show greater fitness on C. quila but not on R. ulmifolius. Considering that C. quila represents a selective force on mandible area, we hypothesized a high adaptive value of this trait, resulting in higher fitness values when nesting on this host, despite its wood is denser and hence more difficult to be bored.

Preference of rabbit does among different nest materials

Directory of Open Access Journals (Sweden)

T.P. Farkas

2018-03-01

Full Text Available Nest quality is important for the survival of new-born rabbits. Nesting material in rabbit farms generally consists of wood shavings, which is completely different from the dry grass used by the European wild rabbit (Oryctolagus cuniculus. The aim of the experiments was to examine which nest materials are preferred by rabbit does when building their nest. In experiment 1, the choice of multiparous rabbit does (n=37 among nest boxes bedded with different nesting materials was monitored. In each pen (1.0×1.83 m 1 doe and 4 nest boxes (0.37×0.23×0.31 m with different nest materials (meadow hay [H], wheat straw [S], fine fibre material [Lignocel®, L] or wood shavings [W] were placed 3 days before the expected parturition (gestation length is about 31 d in the Pannon White breed. Some 48.6% of the does kindled in nest boxes that contained pure materials (L: 40.5%, S: 5.4%, H: 2.7%, and 51.3% of the does kindled in nest boxes where the nest materials of different nest boxes were mixed by the does (S with L: 21.5%, S with L and H: 5.4%, W with L: 8.1%, L with H and S: 5.4%. Does preferred kindling in the nest box bedded with L, and most of them refused the nest box with W. In experiment 2/a (n=32 does and 2/b (n=25 does, each pen (1×0.91 m was equipped with 3 and 2 hay racks and filled with H, S or L, and H or S, respectively. The experiments lasted from the 27th day of pregnancy until the day of parturition and 24-h video recordings (10 does/experiment were evaluated throughout the experiment. The events of carrying the nest materials from the hay racks were registered. In experiment 2/a, the frequency of nest material carrying was highest on the day of parturition. The preferred nest material was L (compared to H and S on each experimental day except day 30 of pregnancy. At the day of kindling, 87.5, 6.3 and 6.3% of the nests contained pure L, mixed L-H and L-S, respectively. In experiment 2/b, the frequency of nest material carrying (mostly S

Solid Oxide Cell and Stack Testing, Safety and Quality Assurance (SOCTESQA)

OpenAIRE

Auer, Corinna; Lang, Michael; Couturier, Karine; Nielsen, Eva Ravn; Mc Phail, Stephen; Tsotridis, Georgios; FU, Qingxi; Chan, Siew Hwa

2015-01-01

The market penetration of fuel and electrolysis cell energy systems in Europe requires the development of reliable assessment, testing and prediction of performance and durability of solid oxide cells and stacks (SOC). To advance in this field the EU-project “SOCTESQA” was launched in May 2014. Partners from different countries in Europe and one external party from Singapore are working together to develop uniform and industry wide test procedures and protocols for SOC cell/stack assembly. In...

Design and performance of tubular flat-plate solid oxide fuel cell

Energy Technology Data Exchange (ETDEWEB)

Matsushima, T.; Ikeda, D.; Kanagawa, H. [NTT Integrated Information & Energy Systems Labs., Tokyo (Japan)] [and others

1996-12-31

With the growing interest in conserving the environmental conditions, much attention is being paid to Solid Oxide Fuel Cell (SOFC), which has high energy-conversion efficiency. Many organizations have conducted studies on tubular and flat type SOFCs. Nippon Telegraph and Telephone Corporation (NTT) has studied a combined tubular flat-plate SOFC, and already presented the I-V characteristics of a single cell. Here, we report the construction of a stack of this SOFC cell and successful generation tests results.

Co-Electrolysis of Steam and Carbon Dioxide in Solid Oxide Cells

DEFF Research Database (Denmark)

Ebbesen, Sune Dalgaard; Knibbe, Ruth; Mogensen, Mogens Bjerg

2012-01-01

Reduction of H2O and CO2 as well as oxidation of H2 and CO was studied in a Ni/YSZ electrode supported Solid Oxide Cell (SOC) produced at DTU Energy conversion (former Risø DTU). Even though these Ni/YSZ based SOCs were developed and optimized for fuel cell use, they can work as reversible SOCs i...

Evaluation of alginate microspheres for mesenchymal stem cell engraftment on solid organ

OpenAIRE

Trouche, E.; Girod Fullana, S.; Mias, C.; Ceccaldi, C.; Tortosa, F.; Seguelas, M. H.; Calise, D.; Parini, A.; Cussac, D.; Sallerin, B.

2010-01-01

Mesenchymal stem cells (MSCs) may be used as a cell source for cell therapy of solid organs due to their differentiation potential and paracrine effect. Nevertheless, optimization of MSC-based therapy needs to develop alternative strategies to improve cell administration and efficiency. One option is the use of alginate microencapsulation, which presents an excellent biocompatibility and an in vivo stability. As MSCs are hypoimmunogenic, it was conceivable to produce microparticles with [algi...

Is it safe to nest near conspicuous neighbours? Spatial patterns in predation risk associated with the density of American Golden-Plover nests.

Science.gov (United States)

Giroux, Marie-Andrée; Trottier-Paquet, Myriam; Bêty, Joël; Lamarre, Vincent; Lecomte, Nicolas

2016-01-01

Predation is one of the main factors explaining nesting mortality in most bird species. Birds can avoid nest predation or reduce predation pressure by breeding at higher latitude, showing anti-predator behaviour, selecting nest sites protected from predators, and nesting in association with protective species. American Golden-Plovers (Pluvialis dominica) defend their territory by using various warning and distraction behaviours displayed at varying levels of intensity (hereafter "conspicuous behaviour"), as well as more aggressive behaviours such as aerial attacks, but only in some populations. Such antipredator behaviour has the potential to repel predators and thus benefit the neighbouring nests by decreasing their predation risk. Yet, conspicuous behaviour could also attract predators by signalling the presence of a nest. To test for the existence of a protective effect associated with the conspicuous antipredator behaviour of American Golden-Plovers, we studied the influence of proximity to plover nests on predation risk of artificial nests on Igloolik Island (Nunavut, Canada) in July 2014. We predicted that the predation risk of artificial nests would decrease with proximity to and density of plover nests. We monitored 18 plover nests and set 35 artificial nests at 30, 50, 100, 200, and 500 m from seven of those plover nests. We found that the predation risk of artificial nests increases with the density of active plover nests. We also found a significant negative effect of the distance to the nearest active protector nest on predation risk of artificial nests. Understanding how the composition and structure of shorebird communities generate spatial patterns in predation risks represents a key step to better understand the importance of these species of conservation concern in tundra food webs.

Fuel cells with solid polymer electrolyte and their application on vehicles

Energy Technology Data Exchange (ETDEWEB)

Fateev, V.

1996-04-01

In Russia, solid polymer electrolyte MF-4-SK has been developed for fuel cells. This electrolyte is based on perfluorinated polymer with functional sulfogroups. Investigations on electrolyte properties and electrocatalysts have been carried out.

A solid oxide fuel cell system for buildings

International Nuclear Information System (INIS)

Zink, Florian; Lu, Yixin; Schaefer, Laura

2007-01-01

This paper examines an integrated solid oxide fuel cell (SOFC) absorption heating and cooling system used for buildings. The integrated system can provide heating/cooling and/or hot water for buildings while consuming natural gas. The aim of this study is to give an overall description of the system. The possibility of such an integrated system is discussed and the configuration of the system is described. A system model is presented, and a specific case study of the system, which consists of a pre-commercial SOFC system and a commercial LiBr absorption system, is performed. In the case study, the detailed configuration of an integrated system is given, and the heat and mass balance and system performance are obtained through numerical calculation. Based on the case study, some considerations with respect to system component selection, system configuration and design are discussed. Additionally, the economic and environmental issues of this specific system are evaluated briefly. The results show that the combined system demonstrates great advantages in both technical and environmental aspects. With the present development trends in solid oxide fuel cells and the commercial status of absorption heating and cooling systems, it is very likely that such a combined system will become increasingly feasible within the following decade

Fermi Potential across Working Solid Oxide Cells with Zirconia or Ceria Electrolytes

DEFF Research Database (Denmark)

Jacobsen, Torben; Chatzichristodoulou, Christodoulos; Mogensen, Mogens Bjerg

2014-01-01

A solid electrolyte will always possess a finite electronic conductivity, in particular electrolytes like doped ceria that easily get reduced and become mixed ionic and electronic conductors. This given rise too high leak currents through the solid oxide cell (SOC). Especially, problems have been...... driving the O2-ions is not the Fermi potential, which is the potential of the electrons, but the Galvani potential (or inner potential) (1). The concepts of potentials describing the electrical situation of a solid electrolyte is shown i Fig. 1, and an example of the Fermi potential (π) and Galvani...

Low heritability of nest construction in a wild bird.

Science.gov (United States)

Järvinen, Pauliina; Kluen, Edward; Brommer, Jon E

2017-10-01

In birds and other taxa, nest construction varies considerably between and within populations. Such variation is hypothesized to have an adaptive (i.e. genetic) basis, but estimates of heritability in nest construction are largely lacking. Here, we demonstrate with data collected over 10 years from 1010 nests built by blue tits in nest-boxes that nest size (height of nest material) and nest composition (proportion of feathers in the nest) are repeatable but only weakly (12-13%) heritable female traits. These findings imply that nest construction may evolve but only if subjected to strong and consistent selection pressures. © 2017 The Author(s).

Plasma Membranes Modified by Plasma Treatment or Deposition as Solid Electrolytes for Potential Application in Solid Alkaline Fuel Cells

Science.gov (United States)

Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

2012-01-01

In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane. PMID:24958295

Plasma membranes modified by plasma treatment or deposition as solid electrolytes for potential application in solid alkaline fuel cells.

Science.gov (United States)

Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

2012-07-30

In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane.

Solid Oxide Fuel Cells Operating on Alternative and Renewable Fuels

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaoxing; Quan, Wenying; Xiao, Jing; Peduzzi, Emanuela; Fujii, Mamoru; Sun, Funxia; Shalaby, Cigdem; Li, Yan; Xie, Chao; Ma, Xiaoliang; Johnson, David; Lee, Jeong; Fedkin, Mark; LaBarbera, Mark; Das, Debanjan; Thompson, David; Lvov, Serguei; Song, Chunshan

2014-09-30

This DOE project at the Pennsylvania State University (Penn State) initially involved Siemens Energy, Inc. to (1) develop new fuel processing approaches for using selected alternative and renewable fuels – anaerobic digester gas (ADG) and commercial diesel fuel (with 15 ppm sulfur) – in solid oxide fuel cell (SOFC) power generation systems; and (2) conduct integrated fuel processor – SOFC system tests to evaluate the performance of the fuel processors and overall systems. Siemens Energy Inc. was to provide SOFC system to Penn State for testing. The Siemens work was carried out at Siemens Energy Inc. in Pittsburgh, PA. The unexpected restructuring in Siemens organization, however, led to the elimination of the Siemens Stationary Fuel Cell Division within the company. Unfortunately, this led to the Siemens subcontract with Penn State ending on September 23rd, 2010. SOFC system was never delivered to Penn State. With the assistance of NETL project manager, the Penn State team has since developed a collaborative research with Delphi as the new subcontractor and this work involved the testing of a stack of planar solid oxide fuel cells from Delphi.

Understanding the processes governing performance and durability of solid oxide electrolysis cells

DEFF Research Database (Denmark)

Ebbesen, Sune Dalgaard; Sun, Xiufu; Mogensen, Mogens Bjerg

2015-01-01

Operation of a Ni–YSZ electrode supported Solid Oxide Cell (SOC) was studied in both fuel cell mode (FC-mode) and electrolysis cell mode (EC-mode) in mixtures of H2O/H2, CO2/CO, H2O/H2O/CO2/CO at 750 °C, 800 °C and 850 °C. Although the SOCs are reversible, the polarisation characterisation shows ...

Thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell in combined heat and power applications

Science.gov (United States)

Abraham, F.; Dincer, I.

2015-12-01

This paper presents a comprehensive steady state modelling and thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell integrated with Gas Turbine power cycle (DU-SOFC/GT). The use of urea as direct fuel mitigates public health and safety risks associated with the use of hydrogen and ammonia. The integration scheme in this study covers both oxygen ion-conducting solid oxide fuel cells (SOFC-O) and hydrogen proton-conducting solid oxide fuel cells (SOFC-H). Parametric case studies are carried out to investigate the effects of design and operating parameters on the overall performance of the system. The results reveal that the fuel cell exhibited the highest level of exergy destruction among other system components. Furthermore, the SOFC-O based system offers better overall performance than that with the SOFC-H option mainly due to the detrimental reverse water-gas shift reaction at the SOFC anode as well as the unique configuration of the system.

Mapping sleeping bees within their nest: spatial and temporal analysis of worker honey bee sleep.

Science.gov (United States)

Klein, Barrett Anthony; Stiegler, Martin; Klein, Arno; Tautz, Jürgen

2014-01-01

Patterns of behavior within societies have long been visualized and interpreted using maps. Mapping the occurrence of sleep across individuals within a society could offer clues as to functional aspects of sleep. In spite of this, a detailed spatial analysis of sleep has never been conducted on an invertebrate society. We introduce the concept of mapping sleep across an insect society, and provide an empirical example, mapping sleep patterns within colonies of European honey bees (Apis mellifera L.). Honey bees face variables such as temperature and position of resources within their colony's nest that may impact their sleep. We mapped sleep behavior and temperature of worker bees and produced maps of their nest's comb contents as the colony grew and contents changed. By following marked bees, we discovered that individuals slept in many locations, but bees of different worker castes slept in different areas of the nest relative to position of the brood and surrounding temperature. Older worker bees generally slept outside cells, closer to the perimeter of the nest, in colder regions, and away from uncapped brood. Younger worker bees generally slept inside cells and closer to the center of the nest, and spent more time asleep than awake when surrounded by uncapped brood. The average surface temperature of sleeping foragers was lower than the surface temperature of their surroundings, offering a possible indicator of sleep for this caste. We propose mechanisms that could generate caste-dependent sleep patterns and discuss functional significance of these patterns.

Effect of Composting Parameters on the Power Performance of Solid Microbial Fuel Cells

Directory of Open Access Journals (Sweden)

Chin-Tsan Wang

2015-09-01

Full Text Available Nowadays, solid organic waste is of major environmental concern and is reaching critical levels worldwide. Currently, a form of natural decomposition, known as composting technology, is widely used to deal with organic waste. This method is applied to enhance the performance of solid microbial fuel cells (SMFCs in this study. Operational composting parameters (carbon/nitrogen ratio, moisture content and pH value are investigated to explore the optimal power performance of solid microbial fuel cells (SMFCs. Results indicate that the carbon/nitrogen ratio and the moisture content displayed the most significant impact on SMFCs. When the carbon/nitrogen ratio is 31.4 and moisture content is 60%, along with a pH value of 6–8, a better SMFC power performance would be obtained. These findings would provide positive information regarding the application of compost in SMFCs.

Is it safe to nest near conspicuous neighbours? Spatial patterns in predation risk associated with the density of American Golden-Plover nests

Directory of Open Access Journals (Sweden)

Marie-Andrée Giroux

2016-08-01

Full Text Available Predation is one of the main factors explaining nesting mortality in most bird species. Birds can avoid nest predation or reduce predation pressure by breeding at higher latitude, showing anti-predator behaviour, selecting nest sites protected from predators, and nesting in association with protective species. American Golden-Plovers (Pluvialis dominica defend their territory by using various warning and distraction behaviours displayed at varying levels of intensity (hereafter “conspicuous behaviour”, as well as more aggressive behaviours such as aerial attacks, but only in some populations. Such antipredator behaviour has the potential to repel predators and thus benefit the neighbouring nests by decreasing their predation risk. Yet, conspicuous behaviour could also attract predators by signalling the presence of a nest. To test for the existence of a protective effect associated with the conspicuous antipredator behaviour of American Golden-Plovers, we studied the influence of proximity to plover nests on predation risk of artificial nests on Igloolik Island (Nunavut, Canada in July 2014. We predicted that the predation risk of artificial nests would decrease with proximity to and density of plover nests. We monitored 18 plover nests and set 35 artificial nests at 30, 50, 100, 200, and 500 m from seven of those plover nests. We found that the predation risk of artificial nests increases with the density of active plover nests. We also found a significant negative effect of the distance to the nearest active protector nest on predation risk of artificial nests. Understanding how the composition and structure of shorebird communities generate spatial patterns in predation risks represents a key step to better understand the importance of these species of conservation concern in tundra food webs.

Hierarchically nested river landform sequences

Science.gov (United States)

Pasternack, G. B.; Weber, M. D.; Brown, R. A.; Baig, D.

2017-12-01

River corridors exhibit landforms nested within landforms repeatedly down spatial scales. In this study we developed, tested, and implemented a new way to create river classifications by mapping domains of fluvial processes with respect to the hierarchical organization of topographic complexity that drives fluvial dynamism. We tested this approach on flow convergence routing, a morphodynamic mechanism with different states depending on the structure of nondimensional topographic variability. Five nondimensional landform types with unique functionality (nozzle, wide bar, normal channel, constricted pool, and oversized) represent this process at any flow. When this typology is nested at base flow, bankfull, and floodprone scales it creates a system with up to 125 functional types. This shows how a single mechanism produces complex dynamism via nesting. Given the classification, we answered nine specific scientific questions to investigate the abundance, sequencing, and hierarchical nesting of these new landform types using a 35-km gravel/cobble river segment of the Yuba River in California. The nested structure of flow convergence routing landforms found in this study revealed that bankfull landforms are nested within specific floodprone valley landform types, and these types control bankfull morphodynamics during moderate to large floods. As a result, this study calls into question the prevailing theory that the bankfull channel of a gravel/cobble river is controlled by in-channel, bankfull, and/or small flood flows. Such flows are too small to initiate widespread sediment transport in a gravel/cobble river with topographic complexity.

Impact of nest sanitation on the immune system of parents and nestlings in a passerine bird.

Science.gov (United States)

Evans, Jessica K; Griffith, Simon C; Klasing, Kirk C; Buchanan, Katherine L

2016-07-01

Bacterial communities are thought to have fundamental effects on the growth and development of nestling birds. The antigen exposure hypothesis suggests that, for both nestlings and adult birds, exposure to a diverse range of bacteria would select for stronger immune defences. However, there are relatively few studies that have tested the immune/bacterial relationships outside of domestic poultry. We therefore sought to examine indices of immunity (microbial killing ability in naive birds, which is a measure of innate immunity, and the antibody response to sheep red blood cells, which measures adaptive immunity) in both adult and nestling zebra finches (Taeniopygia guttata). We did this throughout breeding and between reproductive attempts in nests that were experimentally manipulated to change the intensity of bacterial exposure. Our results suggest that nest sanitation and bacterial load affected measures of the adaptive immune system, but not the innate immune parameters tested. Adult finches breeding in clean nests had a lower primary antibody response to sheep red blood cells, particularly males, and a greater difference between primary and secondary responses. Adult microbial killing of Escherichia coli decreased as parents moved from incubation to nestling rearing for both nest treatments; however, killing of Candida albicans remained consistent throughout. In nestlings, both innate microbial killing and the adaptive antibody response did not differ between nest environments. Together, these results suggest that exposure to microorganisms in the environment affects the adaptive immune system in nesting birds, with exposure upregulating the antibody response in adult birds. © 2016. Published by The Company of Biologists Ltd.

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

Science.gov (United States)

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.

Ultrasensitive quantitation of human papillomavirus type 16 E6 oncogene sequences by nested real time PCR

Directory of Open Access Journals (Sweden)

López-Revilla Rubén

2010-05-01

Full Text Available Abstract Background We have developed an ultrasensitive method based on conventional PCR preamplification followed by nested amplification through real time PCR (qPCR in the presence of the DNA intercalating agent EvaGreen. Results Amplification mixtures calibrated with a known number of pHV101 copies carrying a 645 base pair (bp-long insert of the human papillomavirus type 16 (HPV16 E6 oncogene were used to generate the E6-1 amplicon of 645 bp by conventional PCR and then the E6-2 amplicon of 237 bp by nested qPCR. Direct and nested qPCR mixtures for E6-2 amplification corresponding to 2.5 × 102-2.5 × 106 initial pHV101 copies had threshold cycle (Ct values in the ranges of 18.7-29.0 and 10.0-25.0, respectively. The Ct of qPCR mixtures prepared with 1/50 volumes of preamplified mixtures containing 50 ng of DNA of the SiHa cell line (derived from an invasive cervical cancer with one HPV16 genome per cell was 19.9. Thermal fluorescence extinction profiles of E6-2 amplicons generated from pHV101 and SiHa DNA were identical, with a peak at 85.5°C. Conclusions Our method based on conventional preamplification for 15 cycles increased 10,750 times the sensitivity of nested qPCR for the quantitation of the E6 viral oncogene and confirmed that the SiHa cell line contains one E6-HPV16 copy per cell.

High temperature fuel cell with ceria-based solid electrolyte

International Nuclear Information System (INIS)

Arai, H.; Eguchi, K.; Yahiro, H.; Baba, Y.

1987-01-01

Cation-doped ceria is investigated as an electrolyte for the solid oxide fuel cell. As for application to the fuel cells, the electrolyte are desired to have high ionic conductivity in deriving a large electrical power. A series of cation-doped ceria has higher ionic conductivity than zirconia-based oxides. In the present study, the basic electrochemical properties of cation-doped ceria were studied in relation to the application of fuel cells. The performance of fuel cell with yttria-doped ceria electrolyte was evaluated. Ceria-based oxides were prepared by calcination of oxide mixtures of the components or calcination of co-precipitated hydroxide mixtures from the metal nitrate solution. The oxide mixtures thus obtained were sintered at 1650 0 C for 15 hr in air into disks. Ionic transference number, t/sub i/, was estimated from emf of oxygen concentration cell. Electrical conductivities were measured by dc-4 probe method by varying the oxygen partial pressure. The fuel cell was operated by oxygen and hydrogen

Failure analysis of electrolyte-supported solid oxide fuel cells

Science.gov (United States)

Fleischhauer, Felix; Tiefenauer, Andreas; Graule, Thomas; Danzer, Robert; Mai, Andreas; Kuebler, Jakob

2014-07-01

For solid oxide fuel cells (SOFCs) one key aspect is the structural integrity of the cell and hence its thermo mechanical long term behaviour. The present study investigates the failure mechanisms and the actual causes for fracture of electrolyte supported SOFCs which were run using the current μ-CHP system of Hexis AG, Winterthur - Switzerland under lab conditions or at customer sites for up to 40,000 h. In a first step several operated stacks were demounted for post-mortem inspection, followed by a fractographic evaluation of the failed cells. The respective findings are then set into a larger picture including an analysis of the present stresses acting on the cell like thermal and residual stresses and the measurements regarding the temperature dependent electrolyte strength. For all investigated stacks, the mechanical failure of individual cells can be attributed to locally acting bending loads, which rise due to an inhomogeneous and uneven contact between the metallic interconnect and the cell.

Kinetic and geometric aspects of solid oxide fuel cell electrodes

DEFF Research Database (Denmark)

Mogensen, Mogens Bjerg; Skaarup, Steen

1996-01-01

The paper gives an overview of the main factors controlling the performance of the solid oxide fuel cell (SOFC) electrodes, emphasizing the most widely chosen anodes and cathodes, Ni-YSZ and LSM-YSZ. They are often applied as composites (mixtures) of the electron conducting electrode material...

Common cuckoos Cuculus canorus change their nest-searching strategy according to the number of available host nests

Czech Academy of Sciences Publication Activity Database

Jelínek, Václav; Procházka, Petr; Požgayová, Milica; Honza, Marcel

2014-01-01

Roč. 156, č. 1 (2014), s. 189-197 ISSN 0019-1019 R&D Projects: GA AV ČR IAA600930605; GA AV ČR IAA600930903 Institutional support: RVO:68081766 Keywords : brood parasitism * cuckoo perch * edge effect host aggression * host choice * nest height * nest visibility * nest volume Subject RIV: EG - Zoology Impact factor: 1.921, year: 2014

The study of flow and proton exchange interactions in the cylindrical solid oxide fuel cell

CERN Document Server

Saievar-Iranizad, E

2002-01-01

The solid oxide fuel cell operates at high temperature of about 1000 deg C. In this temperature, some known materials such as Ni, ... which is abundant in the nature, can be used as a catalyst in the electrodes. The electrolytes of such cell solid oxide fuel cell can be made through non-porous solid ceramics such as Zircon's (ZrO sub 2). It can be stabilized using a doped Yttrium oxide. The importance of Yttria-stabilised Zirconia at high temperature belongs to the transport of oxygen ions through the electrolyte. Oxygen using in the hot cathode side causes a considerable reduction in the concentration of oxygen molecules. The oxygen ions exchange through the electrolyte relates to the molecular oxygen concentration gradient between the anode and cathode. Applying fuels such as hydrogen or natural gas in the anode and its chemical reaction with oxygen ions transfer from cathode through the electrolyte, produce electricity, water and heat. To study the ion exchange and its interaction into solid oxide fuel cel...

An economical wireless cavity-nest viewer

Science.gov (United States)

Daniel P. Huebner; Sarah R. Hurteau

2007-01-01

Inspection of cavity nests and nest boxes is often required during studies of cavity-nesting birds, and fiberscopes and pole-mounted video cameras are sometimes used for such inspection. However, the cost of these systems may be prohibitive for some potential users. We describe a user-built, wireless cavity viewer that can be used to access cavities as high as 15 m and...

An all-solid-state lithium/polyaniline rechargeable cell

Science.gov (United States)

Li, Changzhi; Peng, Xinsheng; Zhang, Borong; Wang, Baochen

1992-07-01

The performance of an all-solid-state cell having a lithium negative electrode, a modified polyethylene oxide (PEO)-epoxy resin (ER) electrolyte, and a polyaniline (PAn) positive electrode has been studied using cyclic voltammetry, charge/discharge cycling, and polarization curves at various temperatures. The redox reaction of the PAn electrode at the PAn/modified PEO-ER interface exhibits good reversibility. At 50-80 C, the Li/PEO-ER-LiClO4/PAn cell shows more than 40 charge/discharge cycles, 90 percent charge/discharge efficiency, and 54 W h kg discharge energy density (on PAn weight basis) at 50 micro-A between 2 and 4 V. The polarization performance of the battery improves steadily with increase in temperature.

Effects of accelerated degradation on metal supported thin film-based solid oxide fuel cell

DEFF Research Database (Denmark)

Reolon, R. P.; Sanna, S.; Xu, Yu

2018-01-01

A thin film-based solid oxide fuel cell is deposited on a Ni-based metal porous support by pulsed laser deposition with a multi-scale-graded microstructure design. The fuel cell, around 1 μm in thickness, is composed of a stabilized-zirconia/doped-ceria bi-layered dense electrolyte and nanostruct......A thin film-based solid oxide fuel cell is deposited on a Ni-based metal porous support by pulsed laser deposition with a multi-scale-graded microstructure design. The fuel cell, around 1 μm in thickness, is composed of a stabilized-zirconia/doped-ceria bi-layered dense electrolyte......, electrochemical performances are steady, indicating the stability of the cell. Under electrical load, a progressive degradation is activated. Post-test analysis reveals both mechanical and chemical degradation of the cell. Cracks and delamination of the thin films promote a significant nickel diffusion and new...

Preliminary Electrochemical Characterization of Anode Supported Solid Oxide Cell (AS-SOC) Produced in the Institute of Power Engineering Operated in Electrolysis Mode (SOEC)

Science.gov (United States)

Kupecki, Jakub; Motyliński, Konrad; Skrzypkiewicz, Marek; Wierzbicki, Michał; Naumovich, Yevgeniy

2017-12-01

The article discusses the operation of solid oxide electrochemical cells (SOC) developed in the Institute of Power Engineering as prospective key components of power-to-gas systems. The fundamentals of the solid oxide cells operated as fuel cells (SOFC - solid oxide fuel cells) and electrolysers (SOEC - solid oxide fuel cells) are given. The experimental technique used for electrochemical characterization of cells is presented. The results obtained for planar cell with anodic support are given and discussed. Based on the results, the applicability of the cells in power-to-gas systems (P2G) is evaluated.

Development of solid oxide fuel cell technology

Energy Technology Data Exchange (ETDEWEB)

Kang, Dae Kab; Kim, Sun Jae; Jung, Choong Hwan; Kim, Kyung Hoh; Park, Ji Yun; Oh, Suk Jin [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-01-01

Solid Oxide Fuel Cell (SOFC) technologies that use zirconium oxide as the electrolyte material were studied in this present report. SOFC exhibits a very high power generation efficiency of over 50 %, and does not discharge pollution materials such as dusts, sulfur dioxide, and nitrogen oxide. Zirconia, Ni/YSZ (yttria stabilized zirconia), and La-Sr-Mn-Oxide materials were developed for the electrolyte material, for the anode, and for the cathode, respectively. After making thin zirconia plate using tape casting process, anode and cathode powders were screen printed on the zirconia plate for fabricating unit cells. A test system composed of a vertical tube furnace, digital multimeter, DC current supplier, and measuring circuit was constructed for testing the unit cell performance. This system was controlled by a home-made computer program. Founded on this unit cell technology and system, a multi-stack SOFC system was studied. This system was composed of 10 unit cells each of them had an electrode area of 40 x 40 mm. Based on this system design, large and thin zirconia plates of 70 x 70 mm in area was fabricated for the electrolyte. Different from in the unit cell system, interconnectors are needed in the multi-stack system for connecting unit cells electrically. For this interconnectors, Inconel 750 alloy was selected, sliced into wafers, machined, surface finished, and then Pt-plated. 55 figs, 8 tabs, 51 refs. (Author).

Development of solid oxide fuel cell technology

International Nuclear Information System (INIS)

Kang, Dae Kab; Kim, Sun Jae; Jung, Choong Hwan; Kim, Kyung Hoh; Park, Ji Yun; Oh, Suk Jin

1995-01-01

Solid Oxide Fuel Cell (SOFC) technologies that use zirconium oxide as the electrolyte material were studied in this present report. SOFC exhibits a very high power generation efficiency of over 50 %, and does not discharge pollution materials such as dusts, sulfur dioxide, and nitrogen oxide. Zirconia, Ni/YSZ (yttria stabilized zirconia), and La-Sr-Mn-Oxide materials were developed for the electrolyte material, for the anode, and for the cathode, respectively. After making thin zirconia plate using tape casting process, anode and cathode powders were screen printed on the zirconia plate for fabricating unit cells. A test system composed of a vertical tube furnace, digital multimeter, DC current supplier, and measuring circuit was constructed for testing the unit cell performance. This system was controlled by a home-made computer program. Founded on this unit cell technology and system, a multi-stack SOFC system was studied. This system was composed of 10 unit cells each of them had an electrode area of 40 x 40 mm. Based on this system design, large and thin zirconia plates of 70 x 70 mm in area was fabricated for the electrolyte. Different from in the unit cell system, interconnectors are needed in the multi-stack system for connecting unit cells electrically. For this interconnectors, Inconel 750 alloy was selected, sliced into wafers, machined, surface finished, and then Pt-plated. 55 figs, 8 tabs, 51 refs. (Author)

Nesting Biology and Occurrence of Social Nests in a Bivoltine and Basically Solitary Halictine Bee, Lasioglossum (Lasioglossum) scitulum Smith (Hymenoptera : Halictidae)

OpenAIRE

Ryoichi, MIYANAGA; Yasuo, MAETA; Kazuo, HOSHIKAWA; Division of Environmental Biology, Faculty of Life and Environmental Science, Shimane University; Division of Environmental Biology, Faculty of Life and Environmental Science, Shimane University; Division of Environmental Biology, Faculty of Life and Environmental Science, Shimane University

2000-01-01

The life cycle and sociality of the halictine bee, Lasioglossum (Lasioglossum) scitulum were studied in a greenhouse at Matsue (lat. 35°22′N), south-western Japan in 1988 and 1989. This species was a bivoltine bee with solitary to primitively social behavior. During the summer brooding period of 1988, 51 solitary nests and 8 multi-female nests (3 matrifilial and 5 sororal nests) were discovered. In 1989, 11 multi-female nests (3 matrifilial and 8 sororal nests), together with 59 solitary nest...

Durable solid oxide electrolysis cells and stacks

Energy Technology Data Exchange (ETDEWEB)

Ming Chen

2010-08-15

The purpose of this project was to make a substantial contribution to development of a cost competitive electrolysis technology based on solid oxide cells. The strategy was to address what had been identified as the key issues in previous research projects. Accordingly five lines of work were carried out in the here reported project: 1) Cell and stack element testing and post test characterization to identify major degradation mechanisms under electrolysis operation. 2) Development of interconnects and coatings to allow stable electrolysis operation at approx850 deg. C or above. 3) Development of seals with reduced Si emission. 4) Development of durable SOEC cathodes. 5) Modeling. Good progress has been made on several of the planned activities. The outcome and most important achievements of the current project are listed for the five lines of the work. (LN)

Durability of solid oxide electrolysis cells for hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Hauch, A.; Hoejgaard Jensen, S.; Dalgaard Ebbesen, S.

2007-05-15

In the perspective of the increasing interest in renewable energy and hydrogen economy, the reversible solid oxide cells (SOCs) is a promising technology as it has the potential of providing efficient and cost effective hydrogen production by high temperature electrolysis of steam (HTES). Furthermore development of such electrolysis cells can gain from the results obtained within the R and D of SOFCs. For solid oxide electrolysis cells (SOEC) to become interesting from a technological point of view, cells that are reproducible, high performing and long-term stable need to be developed. In this paper we address some of the perspectives of the SOEC technology i.e. issues such as a potential H2 production price as low as 0.71 US dollar/kg H{sub 2} using SOECs for HTES; is there a possible market for the electrolysers? and what R and D steps are needed for the realisation of the SOEC technology? In the experimental part we present electrolysis test results on SOCs that have been optimized for fuel cell operation but applied for HTES. The SOCs are produced on a pre-pilot scale at Risoe National Laboratory. These cells have been shown to have excellent initial electrolysis performance, but the durability of such electrolysis cells are not optimal and examples of results from SOEC tests over several hundreds of hours are given here. The long-term tests have been run at current densities of -0.5 A/cm{sup 2} and -1 A/cm{sup 2}, temperatures of 850 deg. C and 950 deg. C and p(H{sub 2}O)/p(H{sub 2}) of 0.5/0.5 and 0.9/0.1. Long-term degradation rates are shown to be up to 5 times higher for SOECs compared to similar SOFC testing. Furthermore, hydrogen and synthetic fuel production prices are calculated using the experimental results from long-term electrolysis test as input and a short outlook for the future work on SOECs will be given as well. (au)

Strontium Titanate-based Composite Anodes for Solid Oxide Fuel Cells

DEFF Research Database (Denmark)

Blennow Tullmar, Peter; Kammer Hansen, Kent; Wallenberg, L.R.

2008-01-01

Surfactant-assisted infiltration of Gd-doped ceria (CGO) in Nb-doped SrTiO3 (STN) was investigated as a potential fuel electrode for solid oxide fuel cells (SOFC). An electronically conductive backbone structure of STN was first fabricated at high temperatures and then combined with the mixed con...

Technoeconomy of different solid oxide fuel cell based hybrid cycle

DEFF Research Database (Denmark)

Rokni, Masoud

2014-01-01

Gas turbine, steam turbine and heat engine (Stirling engine) is used as bottoming cycle for a solid oxide fuel cell plant to compare different plants efficiencies, CO2 emissionsand plants cost in terms of $/kW. Each plant is then integrated with biomass gasification and finally six plants...

Medium-temperature solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Maffei, N.; Kuriakose, A.K. [Natural Resources Canada, Ottawa, ON (Canada). Materials Technology Lab

2000-07-01

The Materials Technology Laboratory (MTL) of Natural Resources Canada has been conducting research on the development of a solid oxide fuel cell (SOFC) for the past decade. Fuel cells convert chemical energy directly into electric energy in an efficient and environmentally friendly manner. SOFCs are considered to be good stationary power sources for commercial and residential applications and will likely be commercialized in the near future. The research at MTL has focused on the development of new electrolytes for use in SOFCs. In the course of this research, monolithic planar single cell SOFCs based on doubly doped ceria and lanthanum gallate have been fabricated and tested at 700 degrees C. This paper compared the performance characteristics of both these systems. The data suggested the presence of a significant electronic conductivity in the SOFC incorporating doubly doped ceria, resulting in lower than expected voltage output. The stability of the SOFC, however, did not appear to be negatively affected. The lanthanum gallate based SOFC performed well. It was concluded that reducing the operating temperature of SOFCs would improve their reliability and enhance their operating life. First generation commercial SOFCs will use a zirconium oxide-based electrolytes while second generation units might possibly use ceria-based and/or lanthanum gallate electrolytes. 24 refs., 6 figs.

Study of Seal Glass for Solid Oxide Fuel/Electrolyzer Cells

OpenAIRE

Mahapatra, Manoj Kumar

2009-01-01

Seal glass is essential and plays a crucial role in solid oxide fuel/electrolyzer cell performance and durability. A seal glass should have a combination of thermal, chemical, mechanical, and electrical properties in order to seal different cell components and stacks and prevent gas leakage. All the desired properties can simultaneously be obtained in a seal glass by suitable compositional design. In this dissertation, SrO-La₂O₃-A₂O₃-B₂O₃3-SiO₂ based seal glasses have been developed and compo...

Current status of Westinghouse tubular solid oxide fuel cell program

Energy Technology Data Exchange (ETDEWEB)

Parker, W.G. [Westinghouse Science and Technology Center, Pittsburgh, PA (United States)

1996-04-01

In the last ten years the solid oxide fuel cell (SOFC) development program at Westinghouse has evolved from a focus on basic material science to the engineering of fully integrated electric power systems. Our endurance for this cell is 5 to 10 years. To date we have successfully operated at power for over six years. For power plants it is our goal to have operated before the end of this decade a MW class power plant. Progress toward these goals is described.

Performance Characterization of Solid Oxide Cells Under High Pressure

DEFF Research Database (Denmark)

Sun, Xiufu; Bonaccorso, Alfredo Damiano; Graves, Christopher R.

2015-01-01

on partial pressures (oxygen, steam and hydrogen) were affected by increasing the pressure. In electrolysis mode at low current density, the performance improvement was counteracted by the increase in open circuit voltage, but it has to be borne in mind that the pressurized gas contains higher molar free......In this work, recent pressurized test results of a planar Ni- YSZ (YSZ: Yttria stabilized Zirconia) supported solid oxide cell are presented. Measurements were performed at 800 C in both fuel cell and electrolysis mode at different pressures. A comparison of the electrochemical performance...... of the cell at 1 and 3 bar shows a significant and equal performance gain at higher pressure in both fuel cell mode and electrolysis mode. Electrochemical impedance spectroscopy revealed that the serial resistance was not affected by the operation pressure; all the other processes that are dependent...

Subterranean ant nests: Trace fossils past and future?

OpenAIRE

Tschinkel, Walter R.

2003-01-01

Many species of ants excavate complex, species-typical nests in soil. The basic structural units of many nests are descending tunnels connecting flattened, generally horizontal chambers of oval to lobed outline. The species-typical structure of many nests results from variation in the size, shape, number and arrangement of these basic elements. Nest architecture can be rendered by filling subterranean nests with a thin slurry of orthodontal plaster, then excavating and reconstructing the hard...

Converting nested algebra expressions into flat algebra expressions

NARCIS (Netherlands)

Paredaens, J.; Van Gucht, D.

1992-01-01

Nested relations generalize ordinary flat relations by allowing tuple values to be either atomic or set valued. The nested algebra is a generalization of the flat relational algebra to manipulate nested relations. In this paper we study the expressive power of the nested algebra relative to its

Structural design considerations for micromachined solid-oxide fuel cells

Science.gov (United States)

Srikar, V. T.; Turner, Kevin T.; Andrew Ie, Tze Yung; Spearing, S. Mark

Micromachined solid-oxide fuel cells (μSOFCs) are among a class of devices being investigated for portable power generation. Optimization of the performance and reliability of such devices requires robust, scale-dependent, design methodologies. In this first analysis, we consider the structural design of planar, electrolyte-supported, μSOFCs from the viewpoints of electrochemical performance, mechanical stability and reliability, and thermal behavior. The effect of electrolyte thickness on fuel cell performance is evaluated using a simple analytical model. Design diagrams that account explicitly for thermal and intrinsic residual stresses are presented to identify geometries that are resistant to fracture and buckling. Analysis of energy loss due to in-plane heat conduction highlights the importance of efficient thermal isolation in microscale fuel cell design.

HLA-mismatched hematopoietic stem cell tranplantation for pediatric solid tumors

Directory of Open Access Journals (Sweden)

Andrea Pession

2011-06-01

Full Text Available Even if the overall survival of children with cancer is significantly improved over these decades, the cure rate of high-risk pediatric solid tumors such as neuroblastoma, Ewing’s sarcoma family tumors or rhabdomiosarcoma remain challenging. Autologous hematopoietic stem cell transplantation (HSCT allows chemotherapy dose intensification beyond marrow tolerance and has become a fundamental tool in the multimodal therapeutical approach of these patients. Anyway this procedure does not allow to these children an eventfree survival approaching more than 50% at 5 years. New concepts of allogeneic HSCT and in particular HLA-mismatched HSCT for high risk solid tumors do not rely on escalation of chemo therapy intensity and tumor load reduction but rather on a graft-versus-tumor effect. We here report an experimental study design of HLA-mismatched HSCT for the treatment of pediatric solid tumors and the inherent preliminary results.

Does removal of mammalian predators significantly affect success of simulated nests in linear habitats? Case study on American mink Mustela vison \\& Predation on simulated duck nests in relation to nest density and habitat type

OpenAIRE

PADYŠÁKOVÁ, Eliška

2007-01-01

This thesis is made up of two studies dealing with predation of waterfowl nests. in the first study, we determined wheather removal of introduced predator Mustela vison affected nest survival of simulated duck nests in linear habitat. In the second study, we tested two hypothesis: 1)predation depends on density of waterfowl nests, 2)mammals are main predators in forest habitat and birds mainly depredate nests deployed in open land.

Thermal radiation modelling in a tubular solid oxide fuel cell

International Nuclear Information System (INIS)

Austin, M.E.; Pharoah, J.G.; Vandersteen, J.D.J.

2004-01-01

Solid Oxide Fuel Cells (SOFCs) are becoming the fuel cell of choice among companies and research groups interested in small power generation units. Questions still exist, however, about the operating characteristics of these devices; in particular the temperature distribution in the fuel cell. Using computational fluid dynamics (CFD) a model is proposed that incorporates conduction, convection and radiation. Both surface-to-surface and participating media are considered. It is hoped that a more accurate account of the temperature field in the various flow channels and cell components will be made to assist work on design of fuel cell components and reaction mechanisms. The model, when incorporating radiative heat transfer with participating media, predicts substantially lower operating temperatures and smaller temperature gradients than it does without these equations. It also shows the importance of the cathode air channel in cell cooling. (author)

Co-flow anode/cathode supply heat exchanger for a solid-oxide fuel cell assembly

Science.gov (United States)

Haltiner, Jr., Karl J.; Kelly, Sean M.

2005-11-22

In a solid-oxide fuel cell assembly, a co-flow heat exchanger is provided in the flow paths of the reformate gas and the cathode air ahead of the fuel cell stack, the reformate gas being on one side of the exchanger and the cathode air being on the other. The reformate gas is at a substantially higher temperature than is desired in the stack, and the cathode gas is substantially cooler than desired. In the co-flow heat exchanger, the temperatures of the reformate and cathode streams converge to nearly the same temperature at the outlet of the exchanger. Preferably, the heat exchanger is formed within an integrated component manifold (ICM) for a solid-oxide fuel cell assembly.

Harpy eagle (Harpia harpyja) nesting in manipulated forests

Science.gov (United States)

Alvarez, E.; Ellis, D.H.

1994-01-01

Continental records point to shooting, removal of young and destruction of nests as the primary conservation problems for harpy eagles (Harpia harpyja); bird-observer visits are a new source of concern. Nesting events are roughly 3 yr apart. Nests are used during and after intensive manipulation of the surrounding habitat, and minimum distance between active sites was 3-5 km. In nine nesting sites along a 100-km stretch of the Imalaca Mountains in Venezuela, we fitted five fledglings with satellite-tracked tags from NASA. One of these birds was hacked with the help of the loggers who destroyed its nest. All these nests were active while logging ensued. Out of three renesting attempts, one failed when the nest collapsed. We salvaged two additional fledglings found in captivity. We are monitoring five nests in the buffer area of the Darien National Park in Panama, all within 3 km of human settlements where trees are regularly felled for firewood, lumber, and to clear more cropland. Eagles have been killed at two sites, a third site remains inactive since 1991, and the other two nests currently have fledglings.

Simulating large-scale spiking neuronal networks with NEST

OpenAIRE

Schücker, Jannis; Eppler, Jochen Martin

2014-01-01

The Neural Simulation Tool NEST [1, www.nest-simulator.org] is the simulator for spiking neural networkmodels of the HBP that focuses on the dynamics, size and structure of neural systems rather than on theexact morphology of individual neurons. Its simulation kernel is written in C++ and it runs on computinghardware ranging from simple laptops to clusters and supercomputers with thousands of processor cores.The development of NEST is coordinated by the NEST Initiative [www.nest-initiative.or...

A novel approach to model the transient behavior of solid-oxide fuel cell stacks

Science.gov (United States)

Menon, Vikram; Janardhanan, Vinod M.; Tischer, Steffen; Deutschmann, Olaf

2012-09-01

This paper presents a novel approach to model the transient behavior of solid-oxide fuel cell (SOFC) stacks in two and three dimensions. A hierarchical model is developed by decoupling the temperature of the solid phase from the fluid phase. The solution of the temperature field is considered as an elliptic problem, while each channel within the stack is modeled as a marching problem. This paper presents the numerical model and cluster algorithm for coupling between the solid phase and fluid phase. For demonstration purposes, results are presented for a stack operated on pre-reformed hydrocarbon fuel. Transient response to load changes is studied by introducing step changes in cell potential and current. Furthermore, the effect of boundary conditions and stack materials on response time and internal temperature distribution is investigated.

Jordan Isomorphisms on Nest Subalgebras

Directory of Open Access Journals (Sweden)

Aili Yang

2015-01-01

Full Text Available This paper is devoted to the study of Jordan isomorphisms on nest subalgebras of factor von Neumann algebras. It is shown that every Jordan isomorphism ϕ between the two nest subalgebras algMβ and algMγ is either an isomorphism or an anti-isomorphism.

Gregarious nesting - An anti-predator response in laying hens

DEFF Research Database (Denmark)

Riber, Anja Brinch

2012-01-01

Gregarious nesting can be defined as a behaviour that occurs when a laying hen (Gallus gallus domesticus) given the choice between an occupied and an unoccupied nest site chooses the occupied nest site. It occurs frequently in flocks of laying hens kept under commercial conditions, contrasting...... the behaviour displayed by feral hens that isolate themselves from the flock during nesting activities. What motivates laying hens to perform gregarious nesting is unknown. One possibility is that gregarious nesting is an anti-predator response to the risk of nest predation emerging from behavioural flexibility...

Solid pseudopapillary tumor of pancreas with sickle cell trait: A rare case report

Directory of Open Access Journals (Sweden)

Harish S Permi

2013-01-01

Full Text Available Solid pseudopapillary tumor of pancreas is a rare pancreatic neoplasm affecting young women, has low malignant potential and amenable for surgical excision with good long-term survival. Sickle cell trait is benign condition, which involves one normal beta-globin chain and one HbS chain. Although it is a benign condition, individuals are prone to have rare complications that may predispose to death under certain circumstances. We report a rare coexistence of solid pseudopapillary tumor of pancreas with sickle cell trait in an 18-year-old female who underwent distal pancreatectomy with splenectomy. Histopathological examination and haemoglobin electrophoresis confirmed the diagnosis.

Trap-nests for stingless bees (Hymenoptera, Meliponini)

OpenAIRE

Oliveira , Ricardo; Menezes , Cristiano; Soares , Ademilson; Fonseca , Vera

2012-01-01

International audience; Most stingless bee species build their nests inside tree hollows. In this paper, we present trap-nest containers which simulate nesting cavities so as to attract swarms of stingless bees. Although regularly used by stingless bee beekeepers in Brazil, this technique to obtain new colonies has not yet been systematically studied. We used two different types of trap-nests (plastic and cardboard) of four different sizes (0.5, 1.0, 2.0, and 3.0 L) containing propolis extrac...

Parallel recognition of cancer cells using an addressable array of solid-state micropores.

Science.gov (United States)

Ilyas, Azhar; Asghar, Waseem; Kim, Young-tae; Iqbal, Samir M

2014-12-15

Early stage detection and precise quantification of circulating tumor cells (CTCs) in the peripheral blood of cancer patients are important for early diagnosis. Early diagnosis improves the effectiveness of the therapy and results in better prognosis. Several techniques have been used for CTC detection but are limited by their need for dye tagging, low throughput and lack of statistical reliability at single cell level. Solid-state micropores can characterize each cell in a sample providing interesting information about cellular populations. We report a multi-channel device which utilized solid-state micropores array assembly for simultaneous measurement of cell translocation. This increased the throughput of measurement and as the cells passed the micropores, tumor cells showed distinctive current blockade pulses, when compared to leukocytes. The ionic current across each micropore channel was continuously monitored and recorded. The measurement system not only increased throughput but also provided on-chip cross-relation. The whole blood was lysed to get rid of red blood cells, so the blood dilution was not needed. The approach facilitated faster processing of blood samples with tumor cell detection efficiency of about 70%. The design provided a simple and inexpensive method for rapid and reliable detection of tumor cells without any cell staining or surface functionalization. The device can also be used for high throughput electrophysiological analysis of other cell types. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of nest design, passages, and hybrid on use of nest and production performance of layers in furnished cages.

Science.gov (United States)

Wall, H; Tauson, R; Elwinger, K

2002-03-01

Production performance, including egg quality, and proportion of eggs laid in nests were studied in furnished experimental cages incorporating nests, litter baths, and perches. The study comprised a total of 972 hens of two genotypes: Lohmann Selected Leghorn (LSL) and Hy-Line White. The birds were studied from 20 to 80 wk of age, and conventional four-hen cages were included as a reference. In furnished cages for six hens, the effects of 30 or 50% vs. 100% nest bottom lining (Astro turf) were studied with LSL hens. Nest bottom lining had no significant effect on egg production or proportions of cracked or dirty eggs, but the use of nests was significantly higher in cages incorporating nests with 100% lining, compared with 50 or 30%. The two hybrids were compared when housed in large, group-furnished cages for 14 or 16 hens of two designs; with a rear partition with two pop holes or fully open, i.e., no rear partition. LSL birds produced significantly better and had a significantly lower proportion of cracked eggs. There was no difference between H- and O-cages, either in production or in egg quality. LSL birds laid a significantly lower proportion of eggs in the nests, especially in O-cages, implying a significant hybrid x cage interaction. When housed in conventional cages, the hybrids did not differ in proportion of cracked eggs but differed in production traits. It was concluded that with the present nest design, the proportion of nest bottom lining cannot be reduced without affecting birds' use of nests, but the proportion did not affect exterior egg quality. The effect of genotype should be considered in the further development of furnished cages.

Secondary lithium solid polymer electrolyte cells

International Nuclear Information System (INIS)

Fix, K.A.; Sammells, A.F.

1988-01-01

A strategy for developing morphologically invariant lithium/solid polymer electrolyte interface is being investigated via the use of lithium intercalated electrodes. Emphasis is being placed upon the rutile material Li/sub x/WO/sub 2/ 0.1 < x < 1.0. An absence of shape change at this interface is expected to result in both long cycle life electrochemical cells and the simultaneous maintenance of small interelectrode spacing so that low IR losses can be maintained. During fabrication of cells investigated here both electrochemical and chemical lithium intercalation of WO/sub 2/ was pursued. In the case of larger WO/sub 2/ electrodes initially prepared for fully discharged state cells, electrochemical intercalation during cell charge was found to require significant time, and the reproducible achievement of complete uniform intercalation across the negative electrode became an issue. Emphasis was consequently placed upon cells fabricated using Li/sub x/WO/sub 2/ electrodes initially chemically intercalated by lithium prior to cell assembly. Previous work has demonstrated direct lithium intercalation of metal dichalcogenides using n-BuLi. Lithium activity in n-BuLi is, however, insufficient to achieve lithium intercalation of WO/sub 2//sup 4/. However, recent work has shown that WO/sub 2/ can be directly lithium intercalated upon immersion in lithium naphthalide. Li/sub x/WO/sub 2/ electrodes prepared in this work were intercalated using lithium naphthalide (0.8M) in 2MeTHF. Lithium intercalation was found to readily occur at room temperature, being initially rapid and slowing as bulk intercalation within the electrode proceeded. For electrodes intercalated in this manner, a relationship was identified between the degree of lithium intercalation and initial open-circuit potential in liquid non-aqueous electrolyte

Mapping Sleeping Bees within Their Nest: Spatial and Temporal Analysis of Worker Honey Bee Sleep

Science.gov (United States)

Klein, Barrett Anthony; Stiegler, Martin; Klein, Arno; Tautz, Jürgen

2014-01-01

Patterns of behavior within societies have long been visualized and interpreted using maps. Mapping the occurrence of sleep across individuals within a society could offer clues as to functional aspects of sleep. In spite of this, a detailed spatial analysis of sleep has never been conducted on an invertebrate society. We introduce the concept of mapping sleep across an insect society, and provide an empirical example, mapping sleep patterns within colonies of European honey bees (Apis mellifera L.). Honey bees face variables such as temperature and position of resources within their colony's nest that may impact their sleep. We mapped sleep behavior and temperature of worker bees and produced maps of their nest's comb contents as the colony grew and contents changed. By following marked bees, we discovered that individuals slept in many locations, but bees of different worker castes slept in different areas of the nest relative to position of the brood and surrounding temperature. Older worker bees generally slept outside cells, closer to the perimeter of the nest, in colder regions, and away from uncapped brood. Younger worker bees generally slept inside cells and closer to the center of the nest, and spent more time asleep than awake when surrounded by uncapped brood. The average surface temperature of sleeping foragers was lower than the surface temperature of their surroundings, offering a possible indicator of sleep for this caste. We propose mechanisms that could generate caste-dependent sleep patterns and discuss functional significance of these patterns. PMID:25029445

Mapping sleeping bees within their nest: spatial and temporal analysis of worker honey bee sleep.

Directory of Open Access Journals (Sweden)

Barrett Anthony Klein

Full Text Available Patterns of behavior within societies have long been visualized and interpreted using maps. Mapping the occurrence of sleep across individuals within a society could offer clues as to functional aspects of sleep. In spite of this, a detailed spatial analysis of sleep has never been conducted on an invertebrate society. We introduce the concept of mapping sleep across an insect society, and provide an empirical example, mapping sleep patterns within colonies of European honey bees (Apis mellifera L.. Honey bees face variables such as temperature and position of resources within their colony's nest that may impact their sleep. We mapped sleep behavior and temperature of worker bees and produced maps of their nest's comb contents as the colony grew and contents changed. By following marked bees, we discovered that individuals slept in many locations, but bees of different worker castes slept in different areas of the nest relative to position of the brood and surrounding temperature. Older worker bees generally slept outside cells, closer to the perimeter of the nest, in colder regions, and away from uncapped brood. Younger worker bees generally slept inside cells and closer to the center of the nest, and spent more time asleep than awake when surrounded by uncapped brood. The average surface temperature of sleeping foragers was lower than the surface temperature of their surroundings, offering a possible indicator of sleep for this caste. We propose mechanisms that could generate caste-dependent sleep patterns and discuss functional significance of these patterns.

Nesting success and within-season breeding dispersal in the ...

African Journals Online (AJOL)

Nest predation is a primary cause of nesting mortality for many bird species, particularly passerines. Nest location can affect predation, and it has also been demonstrated that predation risk can alter nest site selection. Birds can limit predation risk by selecting specific habitat characteristics; by changing nest site ...

Colour preferences in nest-building zebra finches.

Science.gov (United States)

Muth, Felicity; Steele, Matthew; Healy, Susan D

2013-10-01

Some bird species are selective in the materials they choose for nest building, preferring, for example, materials of one colour to others. However, in many cases the cause of these preferences is not clear. One of those species is the zebra finch, which exhibits strong preferences for particular colours of nest material. In an attempt to determine why these birds strongly prefer one colour of material over another, we compared the preferences of paired male zebra finches for nest material colour with their preferences for food of the same colours. We found that birds did indeed prefer particular colours of nest material (in most cases blue) but that they did not generally prefer food of one colour over the other colours. It appears, then, that a preference for one colour or another of nest material is specific to the nest-building context. This article is part of a Special Issue entitled: insert SI title. Copyright © 2013 Elsevier B.V. All rights reserved.

Reversible solid oxide fuel cells (R-SOFCs) with chemically stable proton-conducting oxides

KAUST Repository

Bi, Lei

2015-07-01

Proton-conducting oxides offer a promising way of lowering the working temperature of solid oxide cells to the intermediate temperate range (500 to 700. °C) due to their better ionic conductivity. In addition, the application of proton-conducting oxides in both solid oxide fuel cells (SOFCs) and sold oxide electrolysis cells (SOECs) provides unique advantages compared with the use of conventional oxygen-ion conducting conductors, including the formation of water at the air electrode site. Since the discovery of proton conduction in some oxides about 30. years ago, the development of proton-conducting oxides in SOFCs and SOECs (the reverse mode of SOFCs) has gained increased attention. This paper briefly summarizes the development in the recent years of R-SOFCs with proton-conducting electrolytes, focusing on discussing the importance of adopting chemically stable materials in both fuel cell and electrolysis modes. The development of electrode materials for proton-conducting R-SOFCs is also discussed. © 2015 Elsevier B.V.

Landscape distribution of food and nesting sites affect larval diet and nest size, but not abundance of Osmia bicornis.

Science.gov (United States)

Coudrain, Valérie; Rittiner, Sarah; Herzog, Felix; Tinner, Willy; Entling, Martin H

2016-10-01

Habitat fragmentation is a major threat for beneficial organisms and the ecosystem services they provide. Multiple-habitat users such as wild bees depend on both nesting and foraging habitat. Thus, they may be affected by the fragmentation of at least two habitat types. We investigated the effects of landscape-scale amount of and patch isolation from both nesting habitat (woody plants) and foraging habitat (specific pollen sources) on the abundance and diet of Osmia bicornis L. Trap-nests of O. bicornis were studied in 30 agricultural landscapes of the Swiss Plateau. Nesting and foraging habitats were mapped in a radius of 500 m around the sites. Pollen composition of larval diet changed as isolation to the main pollen source, Ranunculus, increased, suggesting that O. bicornis adapted its foraging strategy in function of the nest proximity to main pollen sources. Abundance of O. bicornis was neither related to isolation or amount of nesting habitat nor to isolation or abundance of food plants. Surprisingly, nests of O. bicornis contained fewer larvae in sites at forest edge compared to isolated sites, possibly due to higher parasitism risk. This study indicates that O. bicornis can nest in a variety of situations by compensating scarcity of its main larval food by exploiting alternative food sources. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Parameters influencing charge separation in solid-state dye-sensitized solar cells using novel hole conductors

NARCIS (Netherlands)

Kroeze, J.E.; Hirata, N.; Schmidt-Mende, L.; Orizu, C.; Ogier, S.D.; Carr, K.; Grätzel, M.; Durrant, J.R.

2006-01-01

Solid-state dye-sensitized solar cells employing a solid organic hole-transport material (HTM) are currently under intensive investigation, since they offer a number of practical advantages over liquid-electrolyte junction devices. Of particular importance to the design of such devices is the

Turkey habitat use and nesting characteristics in ponderosa pine

Science.gov (United States)

Mark A. Rumble; Stanley H. Anderson

1987-01-01

Turkeys (Meleagris gallapovo) selected nest sites that provided good horizontal concealment. Rock or rock outcrops were selected most frequently for nest concealment on first-nest attempts. Renest attempts showed a selection preference for shrubs as nest cover; most of these were located in meadows. Nesting success doubled for renests versus first...

Response of predators to Western Sandpiper nest exclosures

Science.gov (United States)

Niehaus, Amanda C.; Ruthrauff, Daniel R.; McCaffery, Brian J.

2004-01-01

In 2001, predator exclosures were used to protect nests of the Western Sandpiper (Calidris mauri) in western Alaska. During the exclosure experiment, nest contents in exclosures had significantly higher daily survival rates than control nests, however, late in the study predators began to cue in on exclosures and predate the nest contents. An Arctic Fox (Alopex lagopus) dug under one exclosure and took the newly hatched chicks, and Long-tailed Jaegers (Stercorarius longicaudus) learned to associate exclosures with active nests and repeatedly visited them. The jaegers attempted to gain access to exclosed nests and pursued adult sandpipers as they emerged from the exclosures. The exclosures were removed to reduce potential mortality to adult and young sandpipers, but subsequently, post-exclosure nests had lower daily survival rates than controls during the same time period. Predation of post-exclosure eggs and chicks highlighted the lasting influence of the exclosure treatment on offspring survival because predators probably remembered nest locations. Researchers are urged to use caution when considering use of predator exclosures in areas where jaegers occur.

Semi-solid electrode cell having a porous current collector and methods of manufacture

Science.gov (United States)

Chiang, Yet-Ming; Carter, William Craig; Cross, III, James C.; Bazzarella, Ricardo; Ota, Naoki

2017-11-21

An electrochemical cell includes an anode, a semi-solid cathode, and a separator disposed therebetween. The semi-solid cathode includes a porous current collector and a suspension of an active material and a conductive material disposed in a non-aqueous liquid electrolyte. The porous current collector is at least partially disposed within the suspension such that the suspension substantially encapsulates the porous current collector.

Incorporation of cigarette butts into nests reduces nest ectoparasite load in urban birds: new ingredients for an old recipe?

Science.gov (United States)

Suárez-Rodríguez, Monserrat; López-Rull, Isabel; Garcia, Constantino Macías

2013-02-23

Birds are known to respond to nest-dwelling parasites by altering behaviours. Some bird species, for example, bring fresh plants to the nest, which contain volatile compounds that repel parasites. There is evidence that some birds living in cities incorporate cigarette butts into their nests, but the effect (if any) of this behaviour remains unclear. Butts from smoked cigarettes retain substantial amounts of nicotine and other compounds that may also act as arthropod repellents. We provide the first evidence that smoked cigarette butts may function as a parasite repellent in urban bird nests. The amount of cellulose acetate from butts in nests of two widely distributed urban birds was negatively associated with the number of nest-dwelling parasites. Moreover, when parasites were attracted to heat traps containing smoked or non-smoked cigarette butts, fewer parasites reached the former, presumably due to the presence of nicotine. Because urbanization changes the abundance and type of resources upon which birds depend, including nesting materials and plants involved in self-medication, our results are consistent with the view that urbanization imposes new challenges on birds that are dealt with using adaptations evolved elsewhere.

Solidification of liquid electrolyte with imidazole polymers for quasi-solid-state dye-sensitized solar cells

International Nuclear Information System (INIS)

Wang Miao; Lin Yuan; Zhou Xiaowen; Xiao Xurui; Yang Lei; Feng Shujing; Li Xueping

2008-01-01

Quasi-solid-state electrolytes were prepared by employing the imidazole polymers to solidify the liquid electrolyte containing lithium iodide, iodine and ethylene carbonate (EC)/propylene carbonate (PC) mixed solvent. The ionic conductivity and diffusion behavior of triiodide in the quasi-solid-state electrolytes were examined in terms of the polymer content. Application of the quasi-solid-state electrolytes to the dye-sensitized solar cells, the maximum energy conversion efficiency of 7.6% (AM 1.5, 100 mW cm -2 ) was achieved. The dependence of the photovoltaic performance on the polymer content and on the different anions of the imidazole polymers was studied by electrochemical impedance spectroscopy and cyclic voltammetry. The results indicate the charge transfer behaviors occurred at nanocrystalline TiO 2 /electrolyte and Pt/electrolyte interface play an important role in influencing the photovoltaic performance of quasi-solid-state dye-sensitized solar cells

Performance characterization of solid oxide cells under high pressure

DEFF Research Database (Denmark)

Sun, Xiufu; Bonaccorso, Alfredo Damiano; Graves, Christopher R.

2014-01-01

in both fuel cell mode and electrolysis mode. In electrolysis mode at low current density, the performance improvement was counteracted by the increase in open circuit voltage, but it has to be born in mind that the pressurised gas contains higher molar free energy. Operating at high current density...... hydrocarbon fuels, which is normally performed at high pressure to achieve a high yield. Operation of SOECs at elevated pressure will therefore facilitate integration with the downstream fuel synthesis and is furthermore advantageous as it increases the cell performance. In this work, recent pressurised test...... results of a planar Ni-YSZ (YSZ: Yttria stabilized Zirconia) supported solid oxide cell are presented. The test was performed at 800 °C at pressures up to 15 bar. A comparison of the electrochemical performance of the cell at 1 and 3 bar shows a significant and equal performance gain at higher pressure...

Chimeric antigen receptor T cell (CAR-T) immunotherapy for solid tumors: lessons learned and strategies for moving forward.

Science.gov (United States)

Li, Jian; Li, Wenwen; Huang, Kejia; Zhang, Yang; Kupfer, Gary; Zhao, Qi

2018-02-13

Recently, the US Food and Drug Administration (FDA) approved the first chimeric antigen receptor T cell (CAR-T) therapy for the treatment CD19-positive B cell acute lymphoblastic leukemia. While CAR-T has achieved remarkable success in the treatment of hematopoietic malignancies, whether it can benefit solid tumor patients to the same extent is still uncertain. Even though hundreds of clinical trials are undergoing exploring a variety of tumor-associated antigens (TAA), no such antigen with comparable properties like CD19 has yet been identified regarding solid tumors CAR-T immunotherapy. Inefficient T cell trafficking, immunosuppressive tumor microenvironment, suboptimal antigen recognition specificity, and lack of safety control are currently considered as the main obstacles in solid tumor CAR-T therapy. Here, we reviewed the solid tumor CAR-T clinical trials, emphasizing the studies with published results. We further discussed the challenges that CAR-T is facing for solid tumor treatment and proposed potential strategies to improve the efficacy of CAR-T as promising immunotherapy.

Research and Development of solar cell frame. Study on solar cell array solid with building material-business building

Energy Technology Data Exchange (ETDEWEB)

1986-08-01

This is a NEDO annual report for 1985. A feasibility study was carried out from the viewpoints demanded both from the building material side and the solar cell. Evaluation from the technical, institutional, and economical viewpoints indicated the possibility of using a roof material solid with carbon-fiber-reinforced concrete and a curtain wall. The solar cell module was verified as a building material to be resistant against the external force, water, and heat. A problem left is how to enlarge the module. Integrated use of CFRC (Carbon Fiber Reinforced Concrete) and a cell of maximum size (1,240 x 700 mm), which is industrially available, can be expected. Present solar cell array can be utilized as a building material as it is for a curtain wall. Cost calculation of the CFRC solid roofing material indicates 276 yen/KWH for 15 years depreciation, 10 % residual value, and 8% annual interest, which is a little expensive, but this cost may be applicable to the use as a curtain wall.

Operation strategy for solid oxide fuel cell systems for small-scale stationary applications

DEFF Research Database (Denmark)

Liso, Vincenzo; Nielsen, Mads Pagh; Kær, Søren Knudsen

2009-01-01

Solid oxide fuel cell micro cogeneration systems have the potential to reduce domestic energy consumption by providing both heat and power on site without transmission losses. The high grade heat produced during the operation of the power causes high thermal transients during startup/shutdown pha......Solid oxide fuel cell micro cogeneration systems have the potential to reduce domestic energy consumption by providing both heat and power on site without transmission losses. The high grade heat produced during the operation of the power causes high thermal transients during startup....../shutdown phases and degrades the fuel cells. To counteract the degradation, the system has not to be stressed with rapid load variation during the operation. The analysis will consider an average profile for heat and power demand of a family house. Finally data analysis and power system limitations will be used...

Feasibility of solid oxide fuel cell dynamic hydrogen coproduction to meet building demand

Science.gov (United States)

Shaffer, Brendan; Brouwer, Jacob

2014-02-01

A dynamic internal reforming-solid oxide fuel cell system model is developed and used to simulate the coproduction of electricity and hydrogen while meeting the measured dynamic load of a typical southern California commercial building. The simulated direct internal reforming-solid oxide fuel cell (DIR-SOFC) system is controlled to become an electrical load following device that well follows the measured building load data (3-s resolution). The feasibility of the DIR-SOFC system to meet the dynamic building demand while co-producing hydrogen is demonstrated. The resulting thermal responses of the system to the electrical load dynamics as well as those dynamics associated with the filling of a hydrogen collection tank are investigated. The DIR-SOFC system model also allows for resolution of the fuel cell species and temperature distributions during these dynamics since thermal gradients are a concern for DIR-SOFC.

Degradation of Solid Oxide Electrolysis Cells Operated at High Current Densities

DEFF Research Database (Denmark)

Tao, Youkun; Ebbesen, Sune Dalgaard; Mogensen, Mogens Bjerg

2014-01-01

In this work the durability of solid oxide cells for co-electrolysis of steam and carbon dioxide (45 % H2O + 45 % CO2 + 10 % H2) at high current densities was investigated. The tested cells are Ni-YSZ electrode supported, with a YSZ electrolyte and either a LSM-YSZ or LSCF-CGO oxygen electrode....... A current density of -1.5 and -2.0 A/cm2 was applied to the cell and the gas conversion was 45 % and 60 %, respectively. The cells were operated for a period of up to 700 hours. The electrochemical analysis revealed significant performance degradation for the ohmic process, oxygen ion interfacial transfer...

Semantic Analysis of Virtual Classes and Nested Classes