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Sample records for complex paraiba state

  1. Sm-Nd isotope geochemistry and U/Pb geochronological data of the Campina Grande complex, Paraiba State, NE Brazil

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    Almeida, C.N. [Pernambuco Univ., Recife, PE (Brazil). Pos-Graduacao em Geociencias; Guimaraes, I.P.; Silva Filho, A.F. da [Pernambuco Univ., Recife, PE (Brazil). Dept. de Geologia; Beurlen, H. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Engenharia de Minas

    1997-12-31

    The Campina Grande Complex (CCG) constitutes a 250 Km{sup 2} intrusion within the high grade gneiss-migmatitic terrain, in the contact zone between the Mesoproterozoic Pajeu-Paraiba Fold Belt and the Archean Caldas Brandao Massif of the Borborema Province, NE Brazil. The contact of the complex is made by the Guarabira Shear Zone (west) and the Campina Grande Shear Zone in the south. The CCG is composed of coarse grained porphyritic quartz-monzonites, quartz-monzodiorites and medium grained porphyritic granodiorites. Mafic enclaves are common and show composition ranging from diorites to quartz diorites. Field and petrographic features point out to magma mixing and mingling processes involved in the CCG evolution. Basalts of probably Cretaceous age occur as dykes cutting in the CCG. This work presents and discusses the Sm-Nd isotope geochemistry of the CCG and a gabro which occur very close to the south contact of the CCG. This also presents the U/Pb in zircon geochronological data for the CCG. (author) 4 refs., 2 figs.

  2. Notes of Recognition of the Potential of Natural Enemies for Farmers in Paraiba State, Brazil

    OpenAIRE

    Josefa Cabral; Paulo Alves Wanderley; José Bruno Malaquias; Luiz Leonardo Ferreira; Flávia Queiroz de Oliveira

    2010-01-01

    To achieve success in using natural enemies in the suppression of insect pests is very important knowledge about the potential of these regulators. Thus, this study aimed to educate small farmers on techniques of identification and conservation of insect predators in agroecosystems of different meso-regions of the state of Paraiba. The training was directed to 15 families in the Assentamento Oziel Pereira, located in the city of Remígio; 10 families in the Reference Center for Social Services...

  3. INFESTATION OF CITRUS BLACK FLY, ALEUROCANTHUS WOGLUMI ASHBY, 1915 (HEMIPTERA: ALEYRODIDAE IN AN AGROECOLOGICAL ORCHARD IN PARAIBA STATE

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    Geisa Mayana Miranda Souza

    2017-05-01

    Full Text Available Aleurocanthus woglumi is present in Paraiba state since 2009, causing a lot of damage to the citrus production in the State. There is a lack of knowledge about the bioecology of this Aleyrodidae member under the climatic conditions of Paraíba State. Thus, in order to know the population density of the pest and study the interference of climatic factors upon these insects, yellow sticky traps were installed evenly distributed in the orchard in the agroecological citrus property in Areia city, in Paraiba state. There were two distinct population peaks of the pest, one in September 2011 and another in April 2012. The lowest densities of the pest were recorded between October and December 2011, a period in which there was no new budding. The population monitoring of A. woglumi in Paraiba state has allowed knowing the time in which the insect occurs in the orchard and the variations in the number of individuals throughout time.

  4. Notes of Recognition of the Potential of Natural Enemies for Farmers in Paraiba State, Brazil

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    Josefa Cabral

    2010-06-01

    Full Text Available To achieve success in using natural enemies in the suppression of insect pests is very important knowledge about the potential of these regulators. Thus, this study aimed to educate small farmers on techniques of identification and conservation of insect predators in agroecosystems of different meso-regions of the state of Paraiba. The training was directed to 15 families in the Assentamento Oziel Pereira, located in the city of Remígio; 10 families in the Reference Center for Social Services in the municipality of Santana de Mangueira, and 7 families in the Site Almeida, located in the municipality of Lagoa Seca. Predators used were: earwig (Doru lineare, ladybugs (Cycloneda sanguinea, syrphidae (Toxomerus sp. and the lacewing (Chrysoperla externa. After viewing insects, there was work to raise awareness about the usefulness of natural enemies presented, where farmers were briefed on techniques for the identification and conservation of these predators in agroecosystems above-mentioned, because no producer recognized the importance hitherto, these predators, most associated as the pests, especially the predators C. sanguinea and Toxomerus sp. for the cultivation of beans and D. lineare for the corn crop.

  5. Quantitative analysis of savanna wood species, in Teixeira, state of Paraiba, Brazil

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    José Adelmo Nunes Leite

    2015-06-01

    Full Text Available Savanna is the vegetation of semi-arid northeastern region of Brazil, which is largely determined by climate and topography. The municipality of Teixeira in the state of Paraiba presents hyperxerophilous shrub-arboreal caatinga land cover, which differs in size and density from those found in Sertaneja Depression, due to higher humidity. The objective of this work was to quantify forest remnant in the municipality of Teixeira, using geographic information system and forest inventory techniques. Native vegetation was mapped using satellite images, from November, 2008. Forest inventory was carried out in 40 sample plots (20 m × 20 m that were selected systematically. Height and diameter at 1.30 m from soil level (DBH were measured in every tree with DBH ≥ 10 cm. Each tree was identified by common and scientific names. A total of 4,911 trees were sampled, representing 46 species and 24 families that corresponds to 3,069 trees ha-1. The species with highest importance value (IV were: Croton sonderianus, Mimosa tenuiflora and Piptadenia stipulacea and the more important families were Euphorbiaceae, Mimosaceae and Caesalpinaceae. The municipality of Teixeira has its best preserved areas in mountainous regions with difficult access.

  6. Rural biodigesters: a discussion on the state of Paraiba - Brazil experience; Biodigestores rurais: uma discussao sobre a experiencia paraibana

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    Oliveira, Leimar de; Castro, Moema Soares de; Oliveira, Aluzilda J. de [Paraiba Univ., Campina Grande, PB (Brazil). Dept. de Engenharia Eletrica. Nucleo de Energia]. E-mail: leimar@nerg.ufpb.br

    1999-07-01

    This work presents data of a large field research involving 76 rural properties, aiming the discussions and investigations on aspects of unifying the biogas supplying, the rural and domestic sectors demands. The analysis have been conducted from the stratified data as function of the final biogas use: cooking, lighting and refrigeration, for the domestic sector, and electric power, heating and electric generation for the agricultural sector. Some results from the Brazilian State of Paraiba experience have been checked viewing the improvement of the energy policies for the rural sector.

  7. Injuries caused by venomous animals and folk medicine in farmers from Cuité, State of Paraiba, Northeast of Brazil

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    Hellyson Fidel Araújo de Oliveira

    2013-09-01

    Full Text Available Injuries caused by venomous animals reported by the agricultural workers from the municipality of Cuité, Curimataú region of Paraiba State, Northeast of Brazil, and the practices of folk medicine which they use to treat these cases were studied in this work from June to August 2010. The farmers studied aged from 11 to 90 years. The number of people who reported cases of injury by these animals in their families was high (89.3%. Scorpions, wasps, bees and snakes were the most cited and the extremities of the body (hands, feet, legs and head were the most affected. The practice of folk medicine to treat these injuries includes various procedures ranging from ritualistic treatments, use of animals or parts of them, and some herbal preparations. The folk treatment was reported as effective by most of the workers injured (63.9%. Body parts of dead snakes are used in various zootherapic treatments. In the imaginary of the agricultural workers the venomous animals are considered hazardous (48.7% or disgusting (11.3%, and several parts of such animals as the rattle, bee sting or snake leather are used as amulet. Several legends have also been reported about snakes, scorpions and bees. The need for educational activities that aim to clarify these workers about the dangers of such practices is urgent.

  8. Dispersal syndromes in the largest protection area of the Atlantic Forest in the state of Paraiba, Brazil

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    Camila Ângelo Jerônimo Domingues

    2013-09-01

    Full Text Available The diaspore dispersal process is crucial for plant reproduction, since the diaspores must reach a suitable site to germinate. This paper aimed to study morphological aspects of diaspores and determine the dispersal syndromes of species occurring in the largest protection area of the Atlantic Forest in the state of Paraiba, Brazil, the Guaribas Biological Reserve. One conducted a monthly collection of fruits/seeds within the period from September 2007 to February 2009. All diaspores of the fruiting species were collected. After analyzing characteristics such as fruit and seed consistency, odor, color, size, and weight, one determined the dispersal syndrome of each species. One collected 3,080 diaspores belonging to 136 different species distributed into 27 families. Zoochory was the most abundant dispersal syndrome (58%, with 79 fruits adapted to it, followed by autochory (29%, and anemochory (13%. Throughout the study period, one found fruiting species, with a predominance of zoochoric fruits, a predictable fact in the Atlantic Forest, which provides fleshy fruits all the year round.

  9. Injuries caused by venomous animals and folk medicine in farmers from Cuité, State of Paraiba, Northeast of Brazil.

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    de Oliveira, Hellyson Fidel Araujo; da Costa, Cristiane Francisca; Sassi, Roberto

    2013-09-01

    Injuries caused by venomous animals reported by the agricultural workers from the municipality of Cuité, Curimataú region of Paraiba State, Northeast of Brazil, and the practices of folk medicine which they use to treat these cases were studied in this work from June to August 2010. The farmers studied aged from 11 to 90 years. The number of people who reported cases of injury by these animals in their families was high (89.3%). Scorpions, wasps, bees and snakes were the most cited and the extremities of the body (hands, feet, legs and head) were the most affected. The practice of folk medicine to treat these injuries includes various procedures ranging from ritualistic treatments, use of animals or parts of them, and some herbal preparations. The folk treatment was reported as effective by most of the workers injured (63.9%). Body parts of dead snakes are used in various zootherapic treatments. In the imaginary of the agricultural workers the venomous animals are considered hazardous (48.7%) or disgusting (11.3%), and several parts of such animals as the rattle, bee sting or snake leather are used as amulet. Several legends have also been reported about snakes, scorpions and bees. The need for educational activities that aim to clarify these workers about the dangers of such practices is urgent.

  10. Snakebite cases in the municipalities of the State of Paraiba, Brazil

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    Hellyson Fidel Araujo De Oliveira

    2013-10-01

    Full Text Available Introduction This study investigated the epidemiological and clinical profile of snakebite cases reported from 2007 to 2012 in the municipalities of the Curimataú region, State of Paraíba, in northeastern Brazil. Methods Data were collected from the Health Department of the State of Paraíba using the Injury Notification Information System data banks of the Health Ministry. Results A total of 304 snakebite cases were studied. The cases occurred most frequently from April to June. The genera Bothrops, Crotalus, and Micrurus were responsible for 74.6%, 6.2%, and 1.3% of cases, respectively. Snakebite cases predominated in males living in rural areas and between 10 and 19 years old. The highest incidence of bites occurred on the feet. The majority of the victims received medical assistance within 1 to 3h after being bitten. With regard to severity, 48% of the cases were classified as mild, 26% as moderate, and 2.6% as severe. Successful cures predominated, and no deaths were reported. The average antivenom ampoule dose used for the treatment in some snakebite cases was lower than that recommended by the Health Ministry. Conclusions Although our results show that Paraíba has a good level of medical care, there are serious deficiencies in recording snakebite information. These data indicate the need to improve the recording process for snakebite cases. Further training for health professionals seems to be necessary to optimize their skills in treating snakebite victims.

  11. Risk factors for Toxoplasma gondii and Neospora caninum seropositivity in buffaloes in Paraiba State, Brazil

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    Arthur Willian de Lima Brasil

    Full Text Available Abstract The aims of this survey were to determine the frequency of anti-Toxoplasma gondii and anti-Neospora caninum antibodies and to identify the risk factors associated with seropositivity among buffaloes in the state of Paraíba, Brazil. This survey included 136 buffaloes belonging to 14 herds. To detect anti-T. gondii and anti-N. caninum antibodies, the indirect fluorescent antibody test (IFAT was used. Among the 136 samples analyzed, 17 (12.5% were positive for anti-T. gondii antibodies with titers ranging from 64 to 1,024, and 26 (19.1% for anti-N. caninum with titers from 200 to 1,600. Animals seropositive for both T. gondii and N. caninum were found in 10 of the 14 herds (71.4%. Semi-intensive management systems (odds ratio = 2.99 and presence of pigs (odds ratio = 4.33 were identified as risk factors for T. gondii and N. caninum, respectively. It can be suggested that T. gondii and N. caninum are widespread in buffaloes in Paraíba, and that additional surveys are needed in order to ascertain the importance of these agents for this species and for pigs, and the influence of the farming type on occurrences of seropositive animals.

  12. Characterization of Paraiba state, Brazil, clays used for clearing of oil of frying for application as bio fuel; Cacterizacao de argilas do estado da Paraiba, Brasil, utilizaadas para clareamento de oleos de fritura usados para aplicacao como biobombustivel

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    Araujo, E.P.; Oliveira, S.V. de; Medeiros, K.M. de; Araujo, E.M.; Fook, M.V.L. [Universidade Federal de Campina Grande (DEMa/UFCG), PB (Brazil). Dept. de Engenharia de Materiais], e-mail: elainepatriciaaraujo@yahoo.com.br

    2008-07-01

    The search for new sources of renewable energy order to minimize environmental impacts has led the scientists to develop new alternatives, such as the use of recycling of frying oils to produce biodiesel. The reuse of these oils has the advantage of obtaining a biofuel with the cost / benefit competitive. However, the conditions of post-consumer oils require treatment prior to its conversion the chemical (transesterification), removing solid particulate contaminants and adjusting its color using the clay of Paraiba. The use of biodiesel as fuel presents a reduction of levels of environmental pollution. This study aimed to characterize clay of Paraiba to be used in the clearing of frying oil. It was observed through the results of the Xray fluorescence (XRF) and infrared spectroscopy by Fourier Transform (FTIR), which the clays tested, have been effective in clearing of frying oils, making them similar to oil 'virgin'. (author)

  13. Treatment of post-consumption oils from Paraiba state - Brazil - clays for application as bio fuel; Tratamento de oleos pos-consumo a partir de argilas da Paraiba para aplicacao como biocombustivel

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    Araujo, E.P.; Oliveira, S.V. de; Medeiros, K.M. de; Silva, D.F. da; Araujo, E.M.; Fook, M.V.L. [Universidade Federal de Campina Grande (DEMa/UFCG), PB (Brazil). Dept. de Engenharia de Materiais], e-mail: elainepatriciaaraujo@yahoo.com.br

    2008-07-01

    The utilization of fuels of agricultural origin in the cycle diesel engines is a good alternative to reduce dependence on importation petroleum, since these fuels are a renewable source of energy. The utilization of biodiesel as biofuel is a contribution to the environment, reducing the qualitative and quantitative form levels of environmental pollution. The recycling of post-consumption oil helps reduce the uncontrolled disposal and environmentally dangerous, than to obtain fuel with a cost / benefit and offering a competitive alternative commercial advantage. However, these oils should go through a process of decontamination and clearing up the stage of chemical conversion which is used clay to lighten the oil. This work had as its objective to make a literature revision evaluating the potential of the clearing clay modified in Paraiba, used in post-consumption oils for application as biofuel. (author)

  14. Intellectual property protection through the geographical indication “Chã de Jardim” of the banana leaf handicrafts (musa sp. in the State of Paraiba

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    Everaldo de França

    2015-11-01

    Full Text Available The construction of a Brazilian Geographical Indication System has been guided by a far wider range of goods, ranging from industrial and agricultural products, services, and even craftwork. Taking into account social, cultural and geographical characteristics, as well as the ethnic constitution of the population of Areia city in the State of Paraiba (Brazil, it is possible to suppose the vast local knowledge that this city’s communities have accumulated over the decades while they seek to incorporate such knowledge in their daily practices. One of the artesanal activities subject to protection of Geographical Indication (IG is the use of banana’s plant (Musa sp. stem as a raw material for some  manufactured products such as handbags, light fixtures, folders for events, cooking utensils etc. The IG records for this type of activity can value the local knowledge regarding the sustainable use of biodiversity and promote the cultural traditions of Areia city, bringing also improvements to the communities involved and consequently increasing the regional development. The identified geographical name to be protected for craftwork is “Chã de Jardim”. It is suggested that “Chã de Jardim” becomes protected by indication of origin whereas the artesanal products of this region feature good reputation. JEL-Code | O33; Q56; R11.

  15. Mavale project: Sensor techniques applied to macrozoning of the Paraiba Valley and littoral north of the State of Sao Paulo

    Science.gov (United States)

    1991-04-01

    This project was designed with two basic objectives in mind. The first is to support the Consortium for Integrated Development of the Paraiba Valley and the Northern Littoral (CODIVAP) for preparation of regulatory guidelines for use of the regional lands. The second is to place at the disposal of the country's technical/scientific community a regional planning method based on the use of Remote Orbital Sensor data. This project involved studies on the following areas: maps - geological, pedological, geomorphological, ground cover, land use, urban area and urban expansion in the last decade, areas favorable for replenishment and concentration of ground water; compartmentation of the region into sub-basins and study of the relationships of land use to surface water quality; generation of a map indicating the suitability of land for civil engineering and urban expansion projects and projects subject to geological risk; preparation of a map showing suitability for agricultural use of the land; and social/economic/demographic analysis. The region of the study encompasses 40 municipalities and portions of 4 others, in an overall region of 18.111 sq. km. Imagery from MSS/Landsat, TM/Landsat, and HRV/SPOT was interpreted, exploring the multispectral, multitemporal, synoptic characteristics as well as the detail (compatible with spatial resolutions of the sensor systems). As a function of the objectives of the different thematic studies involved in the environmental and physical diagnostics, images were interpreted visually or processed digitally in alternate scales of 1:250,000, 1:100,000, or 1:50,000. These studies were complemented with pre-existing bibliographical and cartographic information, and the final mapping products are presented to the scale of 1:250,000, compatible with decisions at the regional level. Thematic studies relative to the physical/territorial, and social/economical reality were integrated in the search for holistic understanding of the region and

  16. Evaluation of demand for water and electricity for papaya micro sprinkler irrigation system in Paraiba state, Brazil; Avaliacao das demandas de agua e energia eletrica para mamao irrigado por microaspersao no estado da Paraiba

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    Lopes, Riuzuani Michelle Bezerra Pedrosa; Dantas Neto, Jose; Farias, Soahd Arruda Rached Farias; Azevedo, Carlos Alberto Vieira de [Universidade Federal de Campina Grande (UAEAG/UFCG), PB (Brazil). Centro de Tecnologia e Recursos Naturais. Unidade Academica de Engenharia Agricola], Emails: riuzuani@yahoo.com.br, zedantas@deag.ufcg.edu.br, soahd_rached@hotmail.com, cazevedo@deag.ufcg.edu.br

    2010-07-01

    This study aimed to conduct an assessment on the demands for water and electricity for fruit irrigated by micro sprinkler irrigation in agricultural planning. We obtained the demands of gross water and electricity for papaya in 15 municipalities spread over the Rio Paraiba-PB, which was used by micro irrigation system with 90% application efficiency. The city of Joao Pessoa is the place to lower water consumption, requiring 32.9% of the amount required for papaya in Exile, which had the highest annual and daily evapotranspiration, combined with the lowest annual rainfall likely at a 75 % probability. The municipalities were chosen because they had a greater variance in terms of climate, in order to examine various irrigation demands. In Exile is a necessary volume of water-to 8.006,9 m{sup 3}.ha{sup -1}.year{sup -1} to produce one hectare of papaya while in Joao Pessoa need to 2.712,89 m{sup 3}.ha-1.year{sup -1}. The consumption of electricity in the city of Desterro is higher among the cities studied, necessitating 2.009,0 kW.ha{sup -1}.ano{sup -1} to produce one hectare of papaya, while in Joao Pessoa we only need 876,54 kW.ha {sup -1}.ano{sup -1} (author)

  17. Geologic evolution of the Paraiba do Sul complex, in the central part of the Ribeira belt, based on the geochemistry and U-Pb geochronology studies; Evolucao geologica do complexo Paraiba do Sul, no segmento central da faixa Ribeira, com base em estudos de geoquimica e geocronologia U-Pb

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    Valladares, Claudia Sayao

    1996-12-31

    Aiming the definition of the Complexo Paraiba do Sul evolution, the work presents a geochronological approach by the U-Pb method, considered appropriate to study polideformed terrains. The minerals used to the U-Pb dating (zircon, titanite and monazite) provides information about the ages of rock generation and the successive geological events the rocks were submitted. The U-Pb geochronological approach is pioneer in the investigated area and two questions referent to the Complexo Paraiba do Sul evolution in the central part of the Ribeira belt, were the aim of this approach. The first of them refers to the crystallization epoch and the gneisses metamorphism, interpreted here like orthogneisses, called Unidade Quirino of the Complexo Paraiba do Sul. The second refers to the metamorphism ages and meta sedimentary unit deformation. Looking for the contribution to the Complexo Paraiba do Sul evolution understanding, this work presents the data based on the geologic map of this area, comprising part of the Folha Volta Redonda (1:50.000), including petrographic, structural and microtectonic studies. It also presents and discusses the results of: 17 U-Pb analysis in zircon and titanite of the Complexo Paraiba do Sul orthogneisses collection; 24 geochemical analysis of major, minor, trace elements and ETR of the same collection; an U-Pb analysis in titanite of the Unidade Sao Joao, 5 U-Pb analysis in titanites and/or monazites of granites and granitoids; 12 geochemical analysis including major, minor and trace elements and ETR, in granites and sills of leucogranites. Finally, the data achieved were integrated with the objective to elaborate an evolutive view of the Complexo Paraiba do Sul 157 refs., 54 figs., 17 tabs.

  18. Determination of the equivalent doses due to the ingestion of radionuclides from the uranium and thorium series presents in drinking waters of the region of Santa Luzia, Paraiba state, Brazil; Determinacao das doses equivalentes devido a ingestao de radionuclideos das series do uranio e torio presentes em aguas de consumo do municipio de Santa Luzia, estado da Paraiba

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    Pastura, Valeria F. da S., E-mail: vpastura@cnen.gov.b [Comissao Nacional de Energia Nuclear (DRSN/CNEN), Rio de Janeiro, RJ (Brazil). Diretoria de Radioprotecao e Seguranca Nuclear. Coordenacao de Materias Primas e Minerais; Campos, Thomas F. da C.; Petta, Reinaldo A., E-mail: thomascampos@geologia.ufrn.b, E-mail: petta@geologia.ufrn.b [Universidade Federal do Rio Grande do Norte (LARANA/UFRN), Natal, RN (Brazil). Lab. de Radioatividade Natural

    2011-10-26

    This paper determined the original dose equivalents from radionuclides of uranium and thorium series in a drinking water of well which is supplied to the population of Santa Luzia, Paraiba state, Brazil. The collected waters are near to the mineralized phlegmatic bodies in rose quartz and amazonite feldspar. Radiometric measurements performed on the feldspar vein point out counting ratios surrounding 30000 cps and the analysis of collected samples of minerals presented tenors for the {sup 226}Ra and {sup 219}Pb varying from 0.50 to 2.30 Bq/sw. For determination of concentration of radionuclides U{sub Total}, {sup 226}Ra, {sup 228}Ra and {sup 219}Pb, found in the not desalinated, two methods were used, spectrophotometry with arsenazo and radiochemistry, both realized in the CNEN-LAPOC laboratories. For the calculation of dose equivalent it was taken into consideration the following parameters: the dose coefficients for incorporation by ingestion for public individuals with ages over 17 years (Norma CNEN-NN-3.01, Regulatory Position 3.01/011) and daily ingestion of 4 liters of water, which is over the recommended by the WHO of 2L/day - 1993. The obtained values were compared with the reference value for compromised dose equivalent established by WHO for evaluate the risk potential to the health of population, by ingestion. The radionuclide concentrations in the wells varies from 0.054 to 0.21 Bq/L, resulting dose equivalents of 3.94 x 10{sup -3} mSv/year and 0.17 mSv/year in the studied population

  19. Soil fertility and {sup 137} Cs redistribution as related to land use, landscape and texture in a watershed of Paraiba State; Fertilidade do solo e redistribuicao de {sup 137} Cs em funcao da cobertura vegetal, relevo, e classes texturais, em uma microbacia hidrografica do Estado da Paraiba

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    Santos, Antonio Clementino dos

    2004-03-15

    Intensive land use and growing deforestation of the natural vegetation in Northeastern Brazil have contributed to the degradation of resources, particularly the decrease of soil fertility. As a result, biodiversity and ecosystem capacity to restore its resources after disturbances have been diminished. The decrease in soil fertility is more substantial in areas dominated by an undulating topography. In these areas, erosion is intensified when crops or pasture replaces natural vegetation. Even though degradation processes are reflected in environmental, social, and economical changes, there is a lack of information regarding the interrelationship between these changes and soil fertility and erosion. Thus, the 'Vaca Brava' watershed (14,04 km{sup 2}), located in the 'Agreste' region of Paraiba State, was selected to study the interrelationships between land use, landscape, particle size distribution, soil fertility and erosion using {sup 137} Cs redistribution. Small farms, where subsistence agriculture is intensive, are common in this watershed, as well as areas for environmental protection. A georreferenced survey of the watershed topography was initially carried out. Based on the survey data, the watershed was digitalized using a scale of 1:5000, and a 3-D map was created. Each landform element had its area determined on a area (absolute value) and percentage (relative value) basis. Shoulder, backslope and footslope positions represented 83% of the cultivated area in the watershed. A data base of 360 georreferenced soil samples (0-20 cm), collected using a stratified sampling scheme, was further created. Sites were stratified based on their landscape position (summit, shoulder, backslope, footslope, and toeslope) in factorial combination with land use (annual crops, pasture, Pennisetum purpureum, Mimosa caesalpiniae folia, bush fallow, and native forest). Physical analyses of the soil samples included particle size distribution and bulk density

  20. Soil fertility and {sup 137} Cs redistribution as related to land use, landscape and texture in a watershed of Paraiba State; Fertilidade do solo e redistribuicao de {sup 137} Cs em funcao da cobertura vegetal, relevo, e classes texturais, em uma microbacia hidrografica do Estado da Paraiba

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Antonio Clementino dos

    2004-03-15

    Intensive land use and growing deforestation of the natural vegetation in Northeastern Brazil have contributed to the degradation of resources, particularly the decrease of soil fertility. As a result, biodiversity and ecosystem capacity to restore its resources after disturbances have been diminished. The decrease in soil fertility is more substantial in areas dominated by an undulating topography. In these areas, erosion is intensified when crops or pasture replaces natural vegetation. Even though degradation processes are reflected in environmental, social, and economical changes, there is a lack of information regarding the interrelationship between these changes and soil fertility and erosion. Thus, the 'Vaca Brava' watershed (14,04 km{sup 2}), located in the 'Agreste' region of Paraiba State, was selected to study the interrelationships between land use, landscape, particle size distribution, soil fertility and erosion using {sup 137} Cs redistribution. Small farms, where subsistence agriculture is intensive, are common in this watershed, as well as areas for environmental protection. A georreferenced survey of the watershed topography was initially carried out. Based on the survey data, the watershed was digitalized using a scale of 1:5000, and a 3-D map was created. Each landform element had its area determined on a area (absolute value) and percentage (relative value) basis. Shoulder, backslope and footslope positions represented 83% of the cultivated area in the watershed. A data base of 360 georreferenced soil samples (0-20 cm), collected using a stratified sampling scheme, was further created. Sites were stratified based on their landscape position (summit, shoulder, backslope, footslope, and toeslope) in factorial combination with land use (annual crops, pasture, Pennisetum purpureum, Mimosa caesalpiniae folia, bush fallow, and native forest). Physical analyses of the soil samples included particle size distribution and bulk density

  1. Caracterização das instalações avícolas na Mesorregião do Agreste Paraibano Characterization of poultry installations in the "Agreste" region of Paraiba State - Brazil

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    Dermeval A. Furtado

    2005-12-01

    Full Text Available Nos últimos anos, as instalações destinadas à produção avícola no Brasil têm-se destacado pelo aumento da densidade de criação que visa a otimizar mão-de-obra, equipamentos, transporte, assistência técnica e, sobretudo, instalações. O objetivo deste trabalho foi realizar pesquisa sobre as principais características tipológicas dos aviários existentes na mesorregião do Agreste do Estado da Paraíba. Observou-se que os aviários são predominantemente concebidos em pequenas dimensões de largura e comprimento, com baixa densidade de alojamento. A grande maioria dos galpões está localizada na direção leste-oeste, com pequena distância entre os aviários, apresentando piso de concreto, cobertura em formato de duas águas, estrutura do telhado em madeira, telhas de barro, ausência de lanternim, pé-direito baixo, beirais pequenos e muretas altas, além de disporem de cobertura vegetal ou outros elementos adequados ao correto paisagismo circundante. Quanto aos equipamentos, observou-se que a principal fonte de aquecimento é de campânulas à lenha, além de bebedouros automáticos pendulares e comedouros manuais. Cerca de 50% dos galpões possuíam ventiladores, mas pequena percentagem desses estava associada a nebulizadores.In the recent years, the installations destined for poultry production in Brazil have been remarkable due to increased bird density which aim to optimize man power, equipment, transport, technical assistance and over all installations. The objective of the present study was to conduct research on principal typological characteristics of poultry houses in the "Agreste" region of Paraiba State, Brazil. It was observed that the poultry houses are conceived in small dimensions of length and width with low housing density. The great majority of the sheds are located in the east-west direction, with short distances between poultry houses with concrete floor, roof tap with two slopes, wood covering structure

  2. Caracterização etnopedológica de Planossolos utilizados em cerâmica artesanal no Agreste Paraibano Ethnopedological studies on solonetz and Planosols used in pottery craftwork in the Agreste region, State of Paraiba

    Directory of Open Access Journals (Sweden)

    Ângelo Giuseppe Chaves Alves

    2005-06-01

    Full Text Available Técnicas adaptadas da etnociência clássica foram utilizadas para descrever e avaliar os conhecimentos de um grupo de artesãos camponeses do Agreste Paraibano sobre alguns solos que eles usam como recurso cerâmico. Cinco perfis de solo foram descritos por agrônomos-pesquisadores (abordagem eticista e por camponeses (abordagem emicista, em locais onde a população local extrai material para cerâmica. Amostras coletadas em ambas as abordagens foram usadas para caracterização morfológica e analítica desses solos. Os camponeses pesquisados foram capazes de distinguir, identificar e nomear diversos materiais de solo, arranjados em estratos ao longo dos perfis de solo, de modo comparável ao arranjo dos horizontes pedogenéticos. A visão, o tato e o paladar foram empregados pelos artesãos na avaliação da qualidade do solo para cerâmica. Quatro perfis descritos junto às fontes de material cerâmico foram classificados como Planossolo Nátrico e um como Planossolo Háplico. A realização de pesquisas etnopedológicas em diferentes contextos sociais e pedológicos pode contribuir para o avanço da ciência do solo, sendo também uma oportunidade para melhor compreender as formas camponesas de conhecimento e manejo de solos.Classic ethnoscientific techniques were adapted to describe and analyze the knowledge of peasant potters about soils they use for making pottery in a rural village in the Agreste region, State of Paraiba, northeastern Brazil. Five soil profiles from pits where local people obtain pottery clay were formally described by researchers (etic approach and by peasant artisans (emic approach. Samples collected during both the emic and etic approaches were used for the morphological and analytical soil characterization. The peasant potters were able to distinguish, identify, and name soil materials arranged in layers along the soil profiles, somehow comparable to the arrangement of the pedogenetic horizons. Vision, touch and

  3. Risk factors associated with BoHV-1 and BVDV seropositivity in buffaloes (Bubalus bubalis from the State of Paraiba, Northeastern Brazil

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    Leise Gomes Fernandes

    2016-08-01

    Full Text Available This study aimed to identify the risk factors associated with Bovine Herpesvirus Type 1 (BoHV-1 and Bovine Viral Diarrhea Virus (BVDV infections in buffaloes in the State of Paraíba, Northeastern Brazil, using 136 female buffaloes ? 24 months old from 14 herds. For the serological diagnosis of the BoHV-1 and BVDV infections, the virus-neutralization test (VN was used and in each herd, an epidemiological questionnaire was applied in order to obtain data to be used in the risk factor analysis. Of the 136 animals 86 (63.2% were positive for BoHV-1 and 12 (8.8% for BVDV. The presence of watering points (odds ratio = 17.68; 95% CI = 3.74 – 83.04 was identified as risk factor for BoHv-1, and animal purchasing was a risk factor for both BoHV-1 (odds ratio = 68.64; 95% CI = 12.28 – 383.73 and BVDV (odds ratio = 3.64; 95% CI = 1.04 – 12.76. The results from the present study showed an evidence of the presence of BoHV-1 and BVDV infections in buffaloes from the State of Paraíba, Northeastern Brazil. It is suggested that control and prevention measures should be adopted, such as the use of diagnostic tests prior to animal purchasing and the use of vaccines to avoid the introduction of infected animals into the herds and the consequent dissemination of the infections, minimizing economic losses.

  4. Perfil sanitário e zootécnico de rebanhos caprinos nas microrregiões do Cariri paraibano Sanitary profile of goat flocks in Cariri micro regions, Paraiba State, Brazil

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    D.A. Bandeira

    2007-12-01

    Full Text Available This work was performed in 60 goat farms located in 15 counties of the micro regions of Western and Eastern Cariri, in Paraiba, to describe and analyze the sanitary profile of the flocks. Visits were done and the answers, obtained from questionnaires that were applied to the farmers, were used. It was observed a mortality of 20% in young animals in 80% of the farms. The presence of technical assistance in 93.3% in the studied farms, adoption of prophylactic calendar in 85% and parasitic control in 83.3% of the flocks were also observed.

  5. Componentes qualitativos do cajá em sete municípios do brejo paraibano = Qualitative components of yellow mombin from seven counties of “Brejo” region in Paraiba State, Brazil

    Directory of Open Access Journals (Sweden)

    Lourival Ferreira Cavalcante

    2009-10-01

    Full Text Available A cajazeira (Spondias mombin L. é uma frutífera nativa com expressivo potencial agroindustrial no Nordeste brasileiro, em razão das qualidades sensoriais dos seus frutos, sendo uma espécie com possibilidade de cultivos comerciais mais extensivos. Neste sentido, objetivouse avaliar as características físicas e químicas de frutos de cajazeira visando o consumo in natura e agroindústria oriundos de plantas espontâneas localizadas nos municípios de Alagoa Grande,Alagoa Nova, Areia, Bananeiras, Borborema, Pilões e Serraria, localizados na Microrregião do Brejo Paraibano. Os tratamentos foram representados por sete municípios, nos quais foram selecionados 5 (cinco plantas espontâneas (repetições e em cada uma foram colhidos 30 (trintafrutos maduros, totalizando 150 (cento e cinqüenta frutos por município estudado avaliados em delineamento inteiramente casualizado. Os frutos foram avaliados quanto aos atributos externose internos: massa, diâmetro transversal e comprimento das sementes, porcentagens de polpa,casca e semente, umidade (%, teor de sólidos solúveis e pH da polpa. Conclui-se que os frutos de cajá avaliados apresentam massa variável de 8,36 a 20,4 g, com teores de sólidos solúveis e pH dentro dos padrões mercadológicos e rendimento em polpa, aquém da exigência das indústrias de processamento.Yellow mombin (Spondias mombin L. is a native fruit species with expressive potential for food industry in North Eastern of Brazil, due to the sensorial quality of its fruit, being a species that should be used for more extensive commercial crops. In this way, this work aimed to evaluate the physical and chemical characteristics of yellow mombin fruits for consumption as fresh or processed fruit from natural plants from Alagoa Grande,Alagoa Nova, Areia, Bananeiras, Borborema, Pilões and Serraria counties, located at “Brejo” microregion of Paraiba State, Brazil. Treatments were represented by seven counties were 5 (five

  6. Crescimento e bromatologia do feijão-bravo (Capparis flexuosa L. em área de Caatinga no Curimataú paraibano, Brasil Growth and bromatology of Capparis flexuosa at Curimatau region, Paraiba state, Brazil

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    Jorge Xavier de Almeida Neto

    2011-06-01

    Full Text Available Este trabalho teve como objetivo caracterizar aspectos relacionados com o crescimento e a bromatologia do feijão-bravo (Capparis flexuosa L. em uma área no Curimataú, Semiárido Paraibano. Para a análise da evolução do crescimento desta espécie formou-se quatro grupos de plantas segundo a classe de altura: GI até 0,50 m; GII de 0,51 a 1 m; GIII de 1,01 a 1,50 m e GIV a >1,51 m. No período de março a dezembro de 2007 determinou-se a altura e o número de ramos dos indivíduos, sendo o diâmetro do caule registrado de março a setembro. Avaliou-se também, a composição bromatológica das folhas e talos do feijão-bravo. Em todos os grupos, o feijão-bravo apresentou crescimento lento no período chuvoso. Entretanto, até o mês de agosto, observou-se o aumento no número de ramos das plantas, independente do grupo estabelecido. No Período amostrado, não se constatou diferença (p > 0,05 entre plantas em termos de diâmetro, em todos os grupos amostrados. Os dados bromatológicos registrados foram os seguintes: matéria orgânica (91,95%; cinzas (8,05%; matéria seca (47,1% e umidade (52,9%. Os teores de proteína bruta (8,13%; fibra bruta (32,32%; extrato etéreo (5,37%; e energia bruta (5.015 cal g-1 do feijão-bravo, dado a estas características, sugerem que esta espécie apresenta potencial para ser utilizada como forrageira.The general aim of this study was to describe the growth and bromatology of Capparis flexuosa L. in an area of Caatinga, Paraiba State, Brazil. To analyze the growth evolution, the plants were divided in four groups according to the height classes: GI until 0.50 m; GII from 0.51 to 1 m; GIII from 1.01 to 1.50 m and GIV above >1.51 m; the plants height, the number of branches and the basal diameter were determined, in the period between March and December, 2007. The bromatological composition of leaves and branches of Capparis flexuosa was evaluated. It was showed, in all groups, that Capparis flexuosa

  7. Complex fermion coherent states

    CERN Document Server

    Tyc, T; Sanders, B C; Oliver, W D; Tyc, Tomas; Hamilton, Brett; Sanders, Barry C.; Oliver, William D.

    2005-01-01

    Whereas boson coherent states provide an elegant, intuitive and useful representation, we show that the desirable features of boson coherent states do not carry over very well to fermion fields unless one is prepared to use exotic approaches such as Grassmann fields. Specifically, we identify four appealing properties of boson coherent states (eigenstate of annihilation operator, displaced vacuum state, preservation of product states under linear coupling, and factorization of correlators) and show that fermion coherent states, and approximations to fermion coherent states, defined over the complex field, do not behave well for any of these four criteria.

  8. Geology of the Curimatau medium region (Paraiba State, Brazil) and the emplacement of the Dona Ines granite associated to the Brasiliano transcurrent shear zones; Geologia da Regiao do Medio Curimatau (PB) e o alojamento do granito de Dona Ines associado a zonas de cisalhamento transcorrentes brasilianas

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Sergio Vieira Freire

    1996-12-31

    In an area of about 700 Km{sup 2} located in the northeast of Paraiba State and having as main point the town of Dona Ines, a geologic/structural mapping, a gravimetric survey and radiometric dating using the Rb/Sr method in whole rock and Sm.Nd model ages were undertaken in order to study and to understand the geology of this portion of terrain, the emplacement of the Dona Ines granitoids and its relationship with the enclosing rocks and the deformation acting at the time of the intrusion. The age of the pluton of Dona Ines was determined by the Rb/Sr whole rock method as 560 {+-} 20 Ma (end of Brasiliano Cycle in the region). Sm.Nd model ages in granitoids of Araras, Belem and Dona Ines have revealed paleoproterozoic ages for their crustal sources, as indicated by the negative {epsilon}{sub nd} of this rock 128 refs., 95 figs., 6 tabs., 7 maps

  9. Neurocysticercosis in Paraiba, Northeast Brazil. An endemic area?

    Science.gov (United States)

    Gonçalves-Coêlho, T D; Coêlho, M D

    1996-12-01

    Neurocysticercosis is the central nervous system infestation by Cysticercus cellulosae, the larval form of Taenia solium. It is related to poor hygiene habits and sanitation; although Northeast is poorest Region of Brazil, it has been always stated as a non-endemic area. After the installation of computed tomography (CT) service, the incidence of neurocysticercosis began to raise in neurology services in Campina Grande PB, a city where people from the interior Paraíba can find specialized medical facilities. We analyse 5,883 CT record of the TomoHPI Computed Tomography Service from August 1993 to December 1995, observing 1.02% suggestive neurocysticercosis cases and classified them according to sex and age, procedence and socioeconomic condition. Distribution of cases according to age is homogeneous until the age of 50 (mean: 28.36 years old). Men and women are equally affected. Urban areas inhabitants represented 83.33%. Residents of Campina Grande represented 48.33% and 48.34% were residents of cities around Campina Grande (until 50 Km around) and other cities of Paraíba State. Fifty-eight patients were dependent to public health care system. We conclude that neurocysticercosis seems to be endemic in Paraiba State, demanding a more detailed study to determine its incidence/prevalence.

  10. Programa Pesquisa para o SUS: a contribuição para gestão e serviços de saúde na Paraíba, Brasil Research program for the Brazilian Unified Health System (SUS: the contribution to health management and services in Paraiba State, Brazil

    Directory of Open Access Journals (Sweden)

    Suely Deysny de Matos Celino

    2013-01-01

    Full Text Available O Programa Pesquisa para o SUS: gestão compartilhada em saúde - PPSUS apresenta o intuito, entre outros, de financiar pesquisas em temas prioritários para a saúde da população brasileira. O objetivo deste estudo de abordagem qualitativa foi compreender a percepção dos pesquisadores sobre a contribuição das pesquisas financiadas pelos editais PPSUS no Estado da Paraíba, para a resolução dos problemas prioritários de saúde da população paraibana, para a redução das desigualdades regionais na área da saúde e para o fortalecimento da gestão do SUS. Realizaram-se levantamento documental nos editais e relatórios finais de pesquisas e, entrevista semiestruturada com 28 coordenadores desses estudos. Utilizou-se estratégia de triangulação de dados e estes foram submetidos à análise de conteúdo, que convergiram para as categorias: resolução dos problemas de saúde; redução das desigualdades regionais; contribuição para a gestão. A Paraíba necessita de ajustes para que o PPSUS possa se efetivar em completude, como a garantia de que o conhecimento gerado possa se concretizar em políticas e ações de saúde, visto que as pesquisas financiadas respondem às necessidades de saúde da população e dificuldades de gestão do SUS.The shared management in health of the Research Program for the Unified Health System (PPSUS has the purpose of funding research in priority areas for the health of the Brazilian population. The scope of this qualitative study is to understand the researchers' perception of the contribution of research funded by the PPSUS invitations to bid in the State of Paraiba, for resolving the priority health problems of the Paraiba population, for reducing regional inequalities in health and for bolstering the management of SUS. A documentary survey of the bids and final reports of research and a semi-structured interview with 28 coordinators of these studies was conducted. Triangulation strategy of data was

  11. SRTXRF analysis in sediments from the Paraiba do Sul river (Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Pareira, Marcelo O.; Calza, Cristiane; Lopes, Ricardo Tadeu [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Lab. de Instrumentacao Nuclear]. E-mail: ccalza@lin.ufrj.br; ricardo@lin.ufrj.br; Anjos, Marcelino Jose dos [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Fisica]. E-mail: marcelin@lin.ufrj.br; Araujo, Francisco Gerson [Universidade Federal Rural do Rio de Janeiro, RJ (Brazil). Lab. de Ecologia de Peixes]. E-mail: gerson@ufrrj.br

    2005-07-01

    The Paraiba do Sul is a medium-sized river located in a region between the two most important urban and industrial centers of Brazil (Rio de Janeiro and Sao Paulo), with 1145 km in length and a drainage basin of 55400 km{sup 2}. Formed by the junction of the Paraibuna and Paraitinga rivers, it arises in Serra da Bocaina (Sao Paulo state) and flows to the Atlantic Ocean until its mouth in Atafona (Rio de Janeiro State). In the last years, has been reported an increase in the water pollution, caused by the untreated domestic sewerage of the inhabitants, effluents discharged by various industries, mining activities and sand extraction of the riverbed. Consequently, a decline in the diversity and abundance of the fish species has been observed. This work used the Total Reflection X-Ray Fluorescence with Synchrotron Radiation (SRTXRF) technique to determine the heavy metals levels in the bioavailable and residual fractions from the surface sediment, in sampling points along the Paraiba do Sul River Basin. The samples were collected from November 2002 to April 2003. The analysis was performed at XRF beamline D09B of the Brazilian Synchrotron Light Laboratory (LNLS), using a white beam for the excitation and a Si(Li) semiconductor detector with resolution of 165 eV. All samples were excited for 100 s. The elements found in the sediment samples were: Ti, Cr, Mn, Fe, Cu, Zn, Rb, Sr, Ba and Pb. (author)

  12. Índices bioclimáticos e produtivos em diferentes galpões avícolas no semiárido paraibano Bioclimatic and production parameters in different poultry houses in the semiarid region of Paraiba State

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    Herlúcio P. da Rocha

    2010-12-01

    Full Text Available Objetivou-se, com este trabalho, analisar os efeitos ambientais sobre o desempenho produtivo de frangos de corte comerciais, criados em dois aviários, localizados na região semiárida paraibana, em condições de verão, sendo um com cobertura de telha de cerâmica e outro coberto com telha de fibrocimento. Não houve diferença significativa entre os galpões (P > 0,05 para temperatura e umidade relativa do ar, índice de temperatura de globo negro e umidade, carga térmica de radiação e a velocidade do vento e os galpões proporcionaram, nos horários considerados mais quentes do dia (10 às 16 h, valores médios considerados acima da zona de conforto, causando situação de desconforto para as aves, mas não influenciaram no seu desempenho produtivo. A temperatura da água nos dois galpões foi superior à recomendada, mas também não influenciou no desempenho produtivo. O nível de pressão sonora dentro dos aviários não causou desconforto às aves nem aos trabalhadores.The aim of this work was to analyse the environmental effects on the productive performance of commercial broiler chickens, raised in two poultry houses located in the semiarid region of Paraiba during the summer months, with one of them covered by a ceramic roof and the other covered with a fibrous cement roof. There was no significant difference between the poultry houses (P > 0.05 for temperature and relative humidity of air, index of black globe temperature and humidity, thermal load of radiation and wind speed. Poultry houses provided during the times considered hotest during the day (10 a.m. to 4 p.m., average values considered above the comfort zone, causing an uncomfortable situation for the animals, but did not influence the productive performance. The water temperature in both poultry houses was higher than recommended, but also did not affect the productive performance. The sound level inside the poultry house did not cause discomfort to the birds or to the

  13. Contribution to the stratigraphy of the onshore Paraiba Basin, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Rossetti, Dilce F.; Valeriano, Marcio M., E-mail: rossetti@dsr.inpe.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Divisao de Sensoriamento Remoto; Goes, Ana M.; Brito-Neves, Benjamim B. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Inst. de Geociencias; Bezerra, Francisco H.R.; Ochoa, Felipe L. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Ciencias Exatas e da Terra. Departamento de Geologia

    2012-06-15

    Several publications have contributed to improve the stratigraphy of the Paraiba Basin in northeastern Brazil. However, the characterization and distribution of sedimentary units in onshore areas of this basin are still incomplete, despite their significance for reconstructing the tectono- sedimentary evolution of the South American passive margin. This work provides new information to differentiate among lithologically similar strata, otherwise entirely unrelated in time. This approach included morphological, sedimentological and stratigraphic descriptions based on surface and sub-surface data integrated with remote sensing, optically stimulated luminescence dating, U+Th/He dating of weathered goethite, and heavy mineral analysis. Based on this study, it was possible to show that Cretaceous units are constrained to the eastern part of the onshore Paraiba Basin. Except for a few outcrops of carbonatic-rocks nearby the modern coastline, deposits of this age are not exposed to the surface in the study area. Instead, the sedimentary cover throughout the basin is constituted by mineralogically and chronologically distinctive deposits, inserted in the Barreiras Formation and mostly in the Post-Barreiras Sediments, of early/middle Miocene and Late Pleistocene-Holocene ages, respectively. The data presented in this work support tectonic deformation as a factor of great relevance to the distribution of the sedimentary units of the Paraiba Basin. (author)

  14. Investigation of wind characteristics and wind energy assessment in Sao Joao do Cariri (SJC) - Paraiba, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Laerte; Filho, Celso

    2010-09-15

    In this study wind characterization and wind energy assessment of the Sao Joao do Cariri (SJC) in Paraiba state situated in Brazilian northeast. The average wind speed and temperature for 25 and 50 m were found 4,74m/s, 24,46C and 5,31m/s 24,25C with wind speed predominate direction of SSE (165 degrees). Weibull shape, scale ,Weibull fit wind speed and Power wind density found 2,54, 5,4m/s, 4,76m/s and 103W/m2 for 25m wind height measurements and 2,59, 6,0m/s, 5,36m/s and 145W/m2 for 50m wind height measurements.

  15. State Complexity of Testing Divisibility

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    Emilie Charlier

    2010-08-01

    Full Text Available Under some mild assumptions, we study the state complexity of the trim minimal automaton accepting the greedy representations of the multiples of m >= 2 for a wide class of linear numeration systems. As an example, the number of states of the trim minimal automaton accepting the greedy representations of the multiples of m in the Fibonacci system is exactly 2m^2.

  16. Spatio-temporal drought characteristics of the tropical Paraiba do Sul River Basin and responses to the Mega Drought in 2014-2016

    Science.gov (United States)

    Nauditt, Alexandra; Metzke, Daniel; Ribbe, Lars

    2017-04-01

    The Paraiba do Sul River Basin (56.000 km2) supplies water to the Brazilian states Sao Paulo and Rio de Janeiro. Their large metropolitan areas were strongly affected by a Mega drought during the years 2014 and 2015 with severe implications for domestic water supply, the hydropower sector as well as for rural agricultural downstream regions. Longer drought periods are expected to become more frequent in the future. However, drought characteristics, low flow hydrology and the reasons for the recurrent water scarcity in this water abundant tropical region are still poorly understood. In order to separate the impact of human abstractions from hydro-climatic and catchment storage related hydrological drought propagation, we assessed the spatio-temporal distribution of drought severity and duration establishing relationships between SPI, SRI and discharge threshold drought anomalies for all subcatchments of the PdS based on a comprehensive hydro-meteorological data set of the Brazilian National Water Agency ANA. The water allocation model "Water Evaluation and Planning System (WEAP)" was established on a monthly basis for the entire Paraiba do Sul river basin incorporating human modifications of the hydrological system as major (hydropower) reservoirs and their operational rules, water diversions and major abstractions. It simulates reasonable discharges and reservoir levels comparable to the observed values. To evaluate the role of climate variability and drought responses for hydrological drought events, scenarios were developed to simulate discharge and reservoir level the impact of 1. Varying meteorological drought frequencies and durations and 2. Implementing operational rules as a response to drought. Uncertainties related to the drought assessment, modelling, parameter and input data were assessed. The outcome of this study for the first time provides an overview on the heterogeneous spatio-temporal drought characteristics of the Paraiba do Sul river basin and

  17. Comparative study of faculties of dentistry of Rio de Janeiro and Universidade Federal da Paraiba in relation to teaching of radiation protection in Dentistry; Estudo comparativo das faculdades de odontologia do Rio de Janeiro e da Universidade Federal da Paraiba no tocante ao ensino da radioprotecao em odontologia

    Energy Technology Data Exchange (ETDEWEB)

    Padilha Filho, L.G. [Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil); Fundacao Tecnico Educacional Souza Marques, Rio de Janeiro, RJ (Brazil); E-mail: lupadilha@ig.com.br; Raymundo Junior, R. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Odontologia; Koch, H.A. [Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil). Dept. de Radiologia; Guedes, W.M.S. [Paraiba Univ., Joao Pessoa, PB (Brazil). Faculdade de Odontologia; Oliveira, L.C.G.; Berquo, F.R.; Cherchinaro, C.C. [Fundacao Tecnico Educacional Souza Marques, Rio de Janeiro, RJ (Brazil). Curso de Fisica

    2001-07-01

    This study compares the qualification and formation in radiation protection, of the students of Dentistry Faculties of Universities in Rio de Janeiro and Paraiba States (Brazil), and recommends the inclusion of Radiation Protection and Image Quality discipline, in the curriculum of Dentistry Faculties, in order to unify the contents and programs in the different study plans. Also to elaborate an appropriate educational training, so that the students of the Brazilian Universities can have the same knowledge about these important themes.

  18. Minimum complexity echo state network.

    Science.gov (United States)

    Rodan, Ali; Tino, Peter

    2011-01-01

    Reservoir computing (RC) refers to a new class of state-space models with a fixed state transition structure (the reservoir) and an adaptable readout form the state space. The reservoir is supposed to be sufficiently complex so as to capture a large number of features of the input stream that can be exploited by the reservoir-to-output readout mapping. The field of RC has been growing rapidly with many successful applications. However, RC has been criticized for not being principled enough. Reservoir construction is largely driven by a series of randomized model-building stages, with both researchers and practitioners having to rely on a series of trials and errors. To initialize a systematic study of the field, we concentrate on one of the most popular classes of RC methods, namely echo state network, and ask: What is the minimal complexity of reservoir construction for obtaining competitive models and what is the memory capacity (MC) of such simplified reservoirs? On a number of widely used time series benchmarks of different origin and characteristics, as well as by conducting a theoretical analysis we show that a simple deterministically constructed cycle reservoir is comparable to the standard echo state network methodology. The (short-term) MC of linear cyclic reservoirs can be made arbitrarily close to the proved optimal value.

  19. Algorithmic complexity and entanglement of quantum states.

    Science.gov (United States)

    Mora, Caterina E; Briegel, Hans J

    2005-11-11

    We define the algorithmic complexity of a quantum state relative to a given precision parameter, and give upper bounds for various examples of states. We also establish a connection between the entanglement of a quantum state and its algorithmic complexity.

  20. Adubação do algodão colorido BRS 200 em sistema orgânico no Seridó Paraibano Fertilization of colored cotton BRS 200 under organic system in Serido, in the State of Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    Melchior N. B. da Silva

    2005-06-01

    Full Text Available É grande a potencialidade do algodão colorido para ser cultivado organicamente na região semi-árida, onde as condições edafoclimáticas possibilitam o cultivo sem defensivos agrícolas. Os adubos orgânicos têm sido utilizados para melhorar as propriedades físico-químicas do solo, o estabelecimento de microrganismos benéficos e o aumento da matéria orgânica, além de ser fonte de nutrientes. O objetivo deste trabalho foi determinar níveis e forma de aplicação do esterco bovino em algodoeiro colorido BRS 200-marrom, cultivado sob manejo orgânico nas condições edafoclimáticas do Seridó Paraibano. O experimento foi conduzido em blocos ao acaso, com nove tratamentos e quatro repetições, nos anos 2000, 2001 e 2002. Os tratamentos se originaram de um fatorial (4 x 2+1, cujos fatores foram quatro níveis de esterco bovino curtido (10, 20, 30 e 40 t ha-1 em dois locais de aplicação (abaixo e ao lado das sementes, adicionado de uma testemunha absoluta sem adubação orgânica. A presença do esterco bovino incrementou a produtividade do algodão. Quando ocorreu regularidade climática, a aplicação ao lado das sementes foi mais eficiente, alcançando-se o máximo rendimento com 30 t ha-1. A uniformidade do comprimento da fibra decresceu e o índice de fibras curtas aumentou com o incremento dos níveis de adubo.The naturally colored cotton has potentiality for growth in Northeast Semi-arid, where the edaphoclimatic conditions permit the cultivation without agrochemicals. Organic fertilizers have been used to improve physico-chemical properties of the soil, establishment of beneficial microorganisms, increase of the organic matter and nutrients. The objective of this work was to determine levels and forms of application of cattle manure in colored cotton BRS 200, cultivated under organic management in Seridó, in the State of Paraiba. The experiment was conducted in randomized blocks, with nine treatments and four replications

  1. Comparative study of ceramic blocks for masonry produced in Paraiba and Rio Grande do Norte; Estudo comparativo de blocos ceramicos para alvenaria produzidos na Paraiba e no Rio Grande do Norte (Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Santos, R.C. dos; Melo, O.B. de; Macedo, R.S. de; Silva, B.J. da; Goncalves, W.P.; Santana, L.N.L., E-mail: renato.materiais@gmail.com [Universidade Federal de Campina Grande (CCT/UAEMa/UFCG), Campina Grande, PB (Brazil). Unidade Acadamica de Engenharia de Materiais. Centro de Ciencias e Tecnologia

    2011-07-01

    The aim of this study to analyze the properties of ceramic blocks produced by the states of Paraiba and Rio Grande do Norte. For this, the raw materials used in the fabrication of these blocks were characterized using the techniques of chemical, granulometry and mineralogical analysis and determination of the plasticity index of mixture ceramic. The properties of the ceramic blocks were determined by evaluating the geometric and visual characteristics and determining the water absorption and compressive strength, according to technical recommendations ABNT NBR 15270. It can be observed that samples have chemical compositions with a predominance of SiO{sub 2} and Al{sub 2}O{sub 3} and Fe{sub 2}O{sub 3} and they are composed of mica, kaolinite, quartz, feldspar and goethite. It was also noted that all blocks showed compressive strength less than 1.5 MPa. (author)

  2. Eficiência de extratores de potássio disponível em solos do estado da Paraíba com graus de desenvolvimento pedogenético diferentes Efficiency of available potassium extractants in soils of Paraiba State with different degrees of pedogenetic development

    Directory of Open Access Journals (Sweden)

    Jailma dos Santos de Medeiros

    2010-02-01

    ássica.Potassium availability for plants depends on the contents of the K forms present in the soils (non exchangeable, exchangeable and soluble K, which vary according to the degree of pedogenetic development of soils. The objective of this study was to evaluate K availability in soils with different degrees of pedogenetic development, based on the extraction of K from the soils with different extractants and with corn plants. Samples of the surface layer (0-30 cm were collected from 12 representative soils in the state of Paraiba, of which six were more and six less developed. To the three replications of all 12 soils, five K doses (0; 50; 100; 200, and 300 mg dm-3 were applied in the form of KCl in solution and incubated for 21 days. Following, a sub-sample of 0.2 dm-3 of each soil was taken to determine the content of available K by the extractors Mehlich-1, Mehlich-3 and ion exchange resin. Then, corn was grown on the soils in a greenhouse for 30 days and the dry matter production and K plant content evaluated. The extractants Mehlich-1, Mehlich-3 and ion exchange resin extracted similar K amounts in the more developed soils. In the group of less developed soils, the extractants Mehlich-1 and Mehlich-3 extracted not very different K amounts, but much greater amounts than by ion exchange resin, especially in the soils with higher clay content and a larger proportion of 2:1 minerals. Unlike the extractants Mehlich-1 and Mehlich-3, ion exchange resin was not well-related with the exchangeable K content in the less developed soils. In this soil group, Mehlich-1 correlated best with the plant K content. In most soils the dry matter production of the plant did not increase with increasing K doses, but in all soils the K plant content increased in response to K fertilization.

  3. Influence of Paraiba uranium deposit in the evaluation of radioecological dosimetry from Sao Mamede- PB

    Energy Technology Data Exchange (ETDEWEB)

    Damascena, Kennedy Francys Rodrigues; Santos Junior, Jose Araujo; Charfuelan, Juana Maria Jimenez; Amaral, Romilton dos Santos; Silva, Alberto Antonio da; Santos, Josineide Marques do Nascimento; Fernandez, Zahily Herrero; Maciel Neto, Jose de Almeida, E-mail: kennedy.eng.ambiental@gmail.com, E-mail: jaraujo@ufpe.br, E-mail: romilton@ufpe.br, E-mail: juanitamariaj@gmail.com, E-mail: neideden@hotmail.com, E-mail: zahily1985@gmail.com, E-mail: profjosemaciel@gmail.com, E-mail: alberto.silva@barreiros.ifpe.edu.br [Universidade Federal de Pernambuco (RAE/DEN/UFPE), Recife, PE (Brazil). Grupo de Estudos em Radioecologia. Departamento de Energia Nuclear

    2015-07-01

    Regions with different levels of natural radionuclides should be investigated from the radioecological viewpoint, to establish protection criteria for environment and the population. The municipality of São Mamede in the state of Paraiba, is one of the closest of the uranium deposit in Espinharas - PB, and can be influenced, given its geological formation, which justifies conducting environmental dosimetric studies. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) established in 2008 a value for the environmental equivalent effective dose rate of 2.44 mSv / y, considering the different forms of exposure and outdoor environments and internal. The calculation for estimating the outdoor dose rate considered a factor of 0.2, which corresponds therefore to a dose rate of 0.46 mSv / y for these environments. The objective of this study was to determine the levels of natural ionizing radiation that municipality using estimated effective dose rate measured in air and 1.0 m from the surface, points to the presence of rocky outcrops using portable detector with discriminator combined probe of NaI (Tl) and BGO. The experimental setup allowed the evaluation of eighty-one points, dose rates ranged from 0.34 to 4.0 mSv / y, with an average of 0.76 mSv / y, exceeding the global average by a factor of 9, which characterizes the need to investigate the dosimetry for internal environments, which can define criteria to check a possible estimate of radioecological risk. (author)

  4. A Price Survey Comparison of Alcoholic Beverages with the Five Basic Food Groups in Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    Charles I. Abramson

    2006-01-01

    Full Text Available The study of alcohol abuse is relatively new in Brazil. Government estimates suggest that 11.2% of the Brazilian population is alcohol dependent. Problems associated with alcohol dependence include domestic violence, increased risk of traffic accidents, poor self-esteem and weak academic performance. A factor known to correlate with alcohol abuse in 12-17 year olds is to have the money necessary to purchase alcoholic beverages. No data is available, however, on the price of alcoholic beverages. The objective of the present study was to provide data on price and to compare the price of alcoholic beverages to basic food items in the Brazilian diet. We also had interest in studying a population in the northeast region of Brazil. This region is the poorest in Brazil, has the highest percentage of alcohol dependency and is seldom the focus of research on dependency. We report that the prices of many alcoholic beverages are less than the price of basic food items. Prices of alcoholic beverages including beer, wine and spirits were compared to the prices of select food items as represented in the Food Pyramid. Food items were selected from the categories of Grain, Dairy, Fruit, Meat and Vegetable. Data was gathered from 32 supermarkets in 8 cities in the northeast state of Paraiba. The price of alcohol is generally less expensive than most basic food group items, especially brands of cachaça (a spirit distilled from sugar cane and beer. Data on price should be considered in any alcohol dependency program in Brazil.

  5. Anticorpos contra o vírus da língua azul em bovinos do sertão da Paraíba Antibodies to bluetongue virus in bovines of Paraíba State, Brazil

    OpenAIRE

    C.B. Melo; Oliveira, A. M. de; Azevedo,E.O.; Z.I.P. Lobato; R.C. Leite

    2000-01-01

    In June of 1997 the prevalence of antibodies to bluetongue virus was between 3.94 and 4.82% in 137 bovine serum samples from 12 herds in Paraiba State, Brazil. This is the first report of antibodies to bluetongue virus in Paraiba State herds.

  6. Impactos da invasão de Prosopis juliflora (sw. DC. (Fabaceae sobre o estrato arbustivo-arbóreo em áreas de Caatinga no Estado da Paraíba, Brasil - doi: 10.4025/actascibiolsci.v32i3.4535 Impact of the invasion of Prosopis juliflora (Sw. DC. (Fabaceae in areas of Caatinga in the state of Paraiba, Brazil - doi: 10.4025/actascibiolsci.v32i3.4535

    Directory of Open Access Journals (Sweden)

    Juliano Ricardo Fabricante

    2010-09-01

    Full Text Available Estima-se que as áreas invadidas por algaroba – Prosopis juliflora (Sw. DC. (Fabaceae no semi-árido nordestino já ultrapassam um milhão de hectares. O presente trabalho objetivou estudar os impactos da invasão de P. juliflora sobre a fitodiversidade e a estrutura do componente arbustivo-arbóreo, em remanescentes de caatinga no Estado da Paraíba. Usando-se o método de parcelas, foram amostrados quatro ambientes, nos quais os indivíduos de todas as espécies arbustivas e arbóreas foram inventariados e medidos, estimando-se os parâmetros estruturais das comunidades. Também foi calculada a diversidade, pelo índice de Shannon-Wiener (H’ e o índice de impacto ambiental de exóticas (IIAE. No total, foram amostradas 19 famílias, 35 gêneros e 39 espécies. A invasora foi responsável por mais de 70% de toda a estrutura dos ambientes inventariados. A baixa diversidade e o elevado valor de impacto ambiental obtidos para os ambientes invadidos revelaram, conjuntamente com os dados de estrutura das populações, os graves impactos que P. juliflora provoca nas comunidades invadidas. Evidencia-se com isso a formação de sistemas monodominados pela espécie invasora, o que revela a necessidade de controle efetivo de P. juliflora para se proteger o patrimônio genético autóctone.It is estimated that invader populations of algaroba Prosopis juliflora (Sw. DC. (Fabaceae in the northeastern semi-arid, Brazil, cover more than one million ha. This study aimed to study the impacts of P. juliflora invasion on phytodiversity and on the structure of the shrub-tree component in caatinga fragments in Paraiba state. Four environments were sampled by plots in which all shrub-tree individuals were surveyed and measured, estimating structural parameters of the communities. Diversity was estimated by the Shannon-Wiener index (H', and the index of environmental impacts of exotic species (IIAE was also calculated. A total of 19 families, 35 genera and 39

  7. Communication complexity reduction from globally uncorrelated states

    Energy Technology Data Exchange (ETDEWEB)

    Wieśniak, Marcin, E-mail: marcin.wiesniak@univie.ac.at

    2015-04-03

    Bell inequality violating entangled states are the working horse for many potential quantum information processing applications, including secret sharing, cryptographic key distribution and communication complexity reduction in distributed computing. Here we explicitly demonstrate the power of certain multi-qubit states to improve the efficiency of partners in joint computation of some multi-qubit function, despite the fact that there could be no correlations between all distributed particles. It is important to stress that the class of functions that can be computed more efficiently is widened, as compared with the standard Bell inequalities. - Highlights: • We expand the set of functions, which can be computed more efficiently with quantum states. • We describe communication complexity reduction protocols based not only on full correlations. • We explicitly show an instance where, a globally uncorrelated state reduces communication complexity.

  8. Multibiomarker approach in fish to assess the impact of pollution in a large Brazilian river, Paraiba do Sul

    Energy Technology Data Exchange (ETDEWEB)

    Linde-Arias, Ana Rosa [Laboratorio de Toxicologia, Centro de Estudos da Saude do Trabalhador e Ecologia Humana, Escola Nacional de Saude Publica Sergio Arouca, Fundacao Oswaldo Cruz, Leopoldo Bulhoes, 1480, Rio de Janeiro (Brazil)], E-mail: arlinde@ensp.fiocruz.br; Inacio, Alan F.; Novo, Leonardo A.; Alburquerque, Carla de; Moreira, Josino C. [Laboratorio de Toxicologia, Centro de Estudos da Saude do Trabalhador e Ecologia Humana, Escola Nacional de Saude Publica Sergio Arouca, Fundacao Oswaldo Cruz, Leopoldo Bulhoes, 1480, Rio de Janeiro (Brazil)

    2008-12-15

    This article examines the advantages of the use of biomarkers as environmental indicators by applying it to Paraiba do Sul watershed, one of the most important Brazilian water bodies, which is in a critical environmental situation. We use a multibiomarker approach in fish as an integrated strategy to assess the impact of pollution. It comprehends a general biomarker of fish health, the condition factor (CF), and specific biomarkers of contaminant exposure such as metallothionein (MT), acetylcholinesterase (AChE) activity and biliary polycyclic aromatic hydrocarbons (PAH) metabolites. Our results revealed different effects in the fish from diverse locations with varying degrees of pollution. Furthermore, fish located just upstream of the water-treatment plant of the metropolitan area of Rio de Janeiro has shown to be affected by metals. This study indicates the usefulness of integrating a set of biomarkers to define the effects of anthropogenic inputs in aquatic bodies under complex polluted situations. - Integrated approach using biomarkers proofs suitable for environmental assessment of a diversely polluted river.

  9. Soil organic matter and soil acidity in Mangrove areas in the river Paraiba Estuary, Cabedelo, Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    Renata Wilma Vasconcelos

    2014-08-01

    Full Text Available Mangrove ecosystems are of great environmental significance, because of their fragility and role in feeding and breeding various animal species. In northeastern Brazil, the disorderly occupation of estuarine areas and the urban sprawl have led to a considerable loss of the original area occupied by mangroves. In the municipality of Cabedelo, State of Paraíba, there are about 4,900 ha of remnant mangrove areas in the estuarine complex of the Paraíba River. However, information about the attributes of mangrove soils at this location is quite scarce. The aim of this study was to quantify the soil organic matter and soil acidity in mangroves located in the estuary of the Paraíba River, State of Paraíba, Brazil, in order to increase the database of soil attributes in this region. The study area is in local influence of the Restinga de Cabedelo National Forest (Flona, an environmental conservation unit of the Chico Mendes Institute for Biodiversity Conservation. For the choice of sampling points, we considered an area that receives direct influence of the eviction of domestic and industrial effluents. The soil of the study area is an “Organossolo Háplico” in Brazilian Soil Classification (Histosol, and was sampled at four point sites: one upstream of the effluent discharge (P1, one in the watercourse receiving effluent water (P2, one downstream of the effluent discharge (P3 and another near Flona (P4, at 0-20 and 20-40 cm, in four replications in time (28/08/2012 in the morning and afternoon, and 21/01/2013 in the morning and afternoon. Potential acidity, pH and soil organic matter (SOM were determined. No significant differences were detected in the potential acidity of the four collection sites, which ranged from 0.38 to 0.45 cmolc dm-3. Soil pH was greatest at point P4 (7.0 and lowest at point P1 (5.8. The SOM was highest at point P1 (86.4 % and lowest at P2 (77.9 %. The attributes related to soil acidity were not sensitive to indicate

  10. Investigating transport capacity equations in sediment yield modelling for the Cariri semi-arid region of Paraiba-PB/Brazil

    Directory of Open Access Journals (Sweden)

    E. E. De Figueiredo

    2015-03-01

    Full Text Available In the semi arid Cariri region of the state of Paraiba, Brazil, runoff is of the Hortonian type generated by excess of rainfall over infiltration capacity, and soil erosion is governed by rainfall intensity and sediment size. However, the governing sediment transport mechanism is not well understood. Sediment transport generally depends on the load of sediment provided by soil erosion and on the transport capacity of the flow. The latter is mainly governed by mechanisms such as water shear stress, or stream power. Accordingly, the load of sediment transported by the flow may vary depending on the mechanism involved in the equation of estimation. Investigation of the sediment transport capacity of the flow via a distributed physically-based model is an important and necessary task, but quite rare in semi-arid climates, and particularly in the Cariri region of the state of Paraíba/Brazil. In this study, the equations of Yalin, Engelund & Hansen, Laursen, DuBoys and Bagnold have been coupled with the MOSEE distributed physically based model aiming at identifying the mechanisms leading to the best model simulations when compared with data observed at various basin scales and land uses in the study region. The results obtained with the investigated methods were quite similar and satisfactory suggesting the feasibility of the mechanisms involved, but the observed values were better represented with Bagnold’s equation, which is physically grounded on the stream power, and we recommend it for simulations of similar climate, runoff generation mechanisms and sediment characteristics as in the study region.

  11. Dosimetry of radium equivalent in construction material of brick works in Sao Jose do Sabugi City - Paraiba, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Eduardo Eudes Nobrega de; Santos Junior, Jose Araujo dos; Amaral, Romilton dos Santos; Santos, Josineide Marques do Nascimento; Spacov, Isabel Cristina Guerra; Fernandez, Zahily Herrero, E-mail: eduardo.eudes@ufpe.br, E-mail: jaraujo@ufpe.br, E-mail: romilton@ufpe.br, E-mail: neideden@hotmail.com, E-mail: isabelspacov@gmail.com, E-mail: zahily1985@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear. Grupo de Radioecologia

    2015-07-01

    The earth's crust has in its composition the Naturally Occurring Radioactive Material (NORM) that may have increased concentration due to activities of exploration and extraction of environmental resources. The civil construction is an economic activity that requires the use of much of the natural resources, such as the raw material of brick works, like clays, mainly used for the production of bricks and tiles. These construction materials may contain high levels of natural radioactive elements, even with concentrations higher than the limits established, given that the levels vary according to the composition of rocks and soil, due to the geological formation and may result in increased exposure of humans to natural radioactive activities. In this context, the radioecological dosimetry is defined in terms of Radium Equivalent activity (Ra{sub eq}), that ensure radiometric conditions for the use of material derived from clays before its final application in housing construction, an initiative that ensures the radioecological safety of population. Thus, this study aimed to establish the calculation of Ra{sub eq} in the raw material of brick works located in Sao Jose do Sabugi city, state of Paraiba, in an area adjacent to the uranium deposits of Espinharas, to estimate the risks associated with primordial radionuclides attributed to TENORM activities (Technologically Enhanced Naturally Occurring Radioactive Materials) from the extraction and use of clay as a raw material in the manufacture of bricks and tiles. Analyses were performed by High Resolution Gamma Spectrometry, with HPGe-Be detector, assuming the state of secular radioactive equilibrium. The results ranged from 183.2 to 747.78 Bq/kg, with an average of 494.6 Bq/kg which exceeded the limit of 370 Bq/kg established by UNSCEAR for construction materials. Some samples obtained values exceeded by up the double this limit, suggesting control and radiometric certification for application of this material

  12. Complex band structure and superlattice electronic states

    Science.gov (United States)

    Schulman, J. N.; McGill, T. C.

    1981-04-01

    The complex band structures of the bulk materials which constitute the alternating layer (001) semiconductor-semiconductor superlattice are investigated. The complex bands near the center of the Brillouin zone in the [001] direction are studied in detail. The decay lengths of superlattice states whose energies lie in the bulk band gaps of one of the semiconductors are determined from the dispersion curves of these bands for imaginary k-->. This method is applied using a tight-binding band-structure calculation to two superlattices: the AlAs-GaAs superlattice and the CdTe-HgTe superlattice. The decay lengths of AlAs-GaAs superlattice conduction-band minimum states are found to be substantially shorter than those for the CdTe-HgTe superlattice. These differences in the decay of the states in the two superlattices result in differences in the variation of the conduction-band effective masses with the thickness of the AlAs and CdTe layers. The conduction-band effective masses increase more rapidly with AlAs thickness in the AlAs-GaAs superlattice than with CdTe thickness in the CdTe-HgTe superlattice.

  13. Exploration potential of Paraiba and Natal platform basins, NE Brazil; Potencial exploratorio das bacias da Paraiba e da plataforma de Natal, NE do Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Jose A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Lima Filho, Mario; Neumann, Virginio H. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Geologia; Maranhao Neto, Jose Carneiro; Araujo, Joao A.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Programa de Pos Graduacao em Geociencias

    2008-07-01

    The portion of Brazilian continental margin located between the Pernambuco Shear Zone (ZCPE) and Touros High, enclosing Natal Platform and Paraiba basin, NE Brazil, presents a thin sedimentary cover represented by Neo- Cretaceous deposits, over an elevated basement. In this zone the narrow platform ends abruptly against the ocean plate, forming a scarped slope. This area corresponds to the Transverse zone of Northeast Brazil (TZN) limited by two extensive transcurrent E-W shear zones that acted as accommodation zones for the strain produced by the advance of the southern and northern rift branches. During the Aptian, the rift suffered a NE deflection and contoured the Borborema Province and the TZN. The resistance of this block to the rift advance generated a prominent and elevated region into the Atlantic gulf which resulted in the absence of rift deposition over the Brazilian margin and its deviation to the African side. The model suggested by this paper denominates this area as the 'exception zone' of the Brazilian margin, which possess a poor petroliferous potential and need to be separated from the sector corresponding to the Pernambuco basin, located to south of ZCPE, representing the last piece of margin before the rift deflection and possessing an important petroliferous potential. (author)

  14. OSL dating results of post-Barreiras sediments in the Paraiba basin, Northeastern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Tudela, Diego R.G.; Munita, Casimiro S., E-mail: drtudela@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Mittani, Juan C.R.; Tatumi, Sonia H., E-mail: tatumi@fatecsp.br [Faculdade de Tecnologia de Sao Paulo (FATEC-SP/CEETEPS), Laboratorio de Datacao e Luminescencia de Cristais, Sao Paulo, SP (Brazil); Rossetti, Dilce F., E-mail: rossetti@dsr.inpe.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Centro de Observacao da Terra, Divisao de Sensoriamento Remoto - DSR

    2011-07-01

    In the present study we show ages of 39 sediments samples of two sedimentary units (PB1 and PB2) collected from Paraiba Basin, northeastern Brazil, obtained by optically stimulated luminescence (OSL) making use of standardized growth curve (SGC) and applying single aliquot regenerative dose (SAR) protocol in 15 randomly selected samples to validate the equivalent Dose (D{sub e}). Environmental radiation dosimetry of the area was performed to evaluate the natural concentrations of {sup 238}U, {sup 232}Th and {sup 40}K and in this way annual dose rates of the locations were evaluated. The results showed natural radioisotopes concentrations between 0.542-4.879 ppm for U, 1.314-26.098 ppm for Th and 0.141-1.12% for K and annual dose rates between 439-4172{mu}Gy/yr. The ages ranged from 1.8-178.3 kyr were obtained, and they are in agreements with the geological considerations. (author)

  15. Mapping ecological states in a complex environment

    Science.gov (United States)

    Steele, C. M.; Bestelmeyer, B.; Burkett, L. M.; Ayers, E.; Romig, K.; Slaughter, A.

    2013-12-01

    analysis provides a platform for classification that more closely resembles human recognition of objects within a remotely sensed image. The analysis presented here compares multiple thematic maps created for test locations on the USDA-ARS Jornada Experimental Range ranch. Three study sites in different pastures, each 300 ha in size, were selected for comparison on the basis of their ecological site type (';Clayey', ';Sandy' and a combination of both) and the degree of complexity of vegetation cover. Thematic maps were produced for each study site using (i) manual interpretation of digital aerial photography (by five independent interpreters); (ii) object-oriented, decision-tree classification of fine and moderate spatial resolution imagery (Quickbird; Landsat Thematic Mapper) and (iii) ground survey. To identify areas of uncertainty, we compared agreement in location, areal extent and class assignation between 5 independently produced, manually-digitized ecological state maps and with the map created from ground survey. Location, areal extent and class assignation of the map produced by object-oriented classification was also assessed with reference to the ground survey map.

  16. Silviculture of eucaliptus plantations in the Paraiba do Sul basin, Brazil, and its potential implication on the basin ecohydrology.

    Science.gov (United States)

    Carriello, Felix; Andres Rodriguez, Daniel; Marques Neves, Otto; Vicens, Raul

    2014-05-01

    Silviculture of eucaliptus plantations is an important driver of the Mata Atlântica biome conversion into another land use in the Paraíba do Sul basin, in the southeastern of Brazil. This region is located in one of the most developed areas in Brazil, between Rio de Janeiro and São Paulo, the most important cities in Brazil, linked by Presidente Dutra highway. Between both cities there are another cities that produce a variety of goods - from meat to planes, cars and mobile phones. This area is, at the same time, one the most important hot spot for the Mata Atlântica biome. Here we have a large Mata Atlântica fragment protected by law and others fragments being conversed to pasture, agriculture, silviculture and urban areas. Paraiba do Sul river drains the region and runs into Rio de Janeiro State. The basin is highly anthropized, with multiple approaches of its waters resources. Its waters also serve Rio de Janeiro metropolitan area. Because land use and land cover changes impact the water yield in a basin, the study of its dynamic its of great importance for water resources management. We study the land use and land cover change in the region between 1986 and 2010, focusing in the development of silviculture of eucaliptus plantations. We used the HAND (Height Above Nearest Drainage) approach that uses the height above the nearest water body, acquired from SRTM Data and transformed into a Terrain Numeric Mode, to classify the landscape into three different ecohydrological environments: floodplain, mountain top and hillslope. This classes were intersected with 1986 and 2010 land use and cover change classification obtained from Landsat imagery. Results show that silviculture has increased in the region from 1986 to 2010. In both years, silviculture areas are mainly located at the hillslope (47%), while floodplain and mountain top share 28 % and 23 % respectively. Available census data from the Brazilian Institute of Geography and Statistics, IBGE, for 1995 and

  17. Identificação e avaliação de práticas de produção enxuta em empresas calçadistas do estado da Paraíba/Identification and evaluation of lean production practices in footwear companies in the state of Paraíba

    National Research Council Canada - National Science Library

    Luciano Costa Santos; Cláudia Fabiana Gohr; Juliana Maria Silva Gonçalves; Flora Magna do Monte Vilar; Leonardo de Miranda Arnaud

    2017-01-01

    .... Considering the economic importance of the footwear industry for the State of Paraiba, this paper presents an exploratory study in five relevant factories to the region in order to obtain an initial...

  18. Correlation/Communication complexity of generating bipartite states

    OpenAIRE

    Jain, Rahul; Shi, Yaoyun; Wei, Zhaohui; Zhang, Shengyu

    2012-01-01

    We study the correlation complexity (or equivalently, the communication complexity) of generating a bipartite quantum state $\\rho$. When $\\rho$ is a pure state, we completely characterize the complexity for approximately generating $\\rho$ by a corresponding approximate rank, closing a gap left in Ambainis, Schulman, Ta-Shma, Vazirani and Wigderson (SIAM Journal on Computing, 32(6):1570-1585, 2003). When $\\rho$ is a classical distribution $P(x,y)$, we tightly characterize the complexity of gen...

  19. Correlation/Communication complexity of generating bipartite states

    CERN Document Server

    Jain, Rahul; Wei, Zhaohui; Zhang, Shengyu

    2012-01-01

    We study the correlation complexity (or equivalently, the communication complexity) of generating a bipartite quantum state $\\rho$. When $\\rho$ is a pure state, we completely characterize the complexity for approximately generating $\\rho$ by a corresponding approximate rank, closing a gap left in Ambainis, Schulman, Ta-Shma, Vazirani and Wigderson (SIAM Journal on Computing, 32(6):1570-1585, 2003). When $\\rho$ is a classical distribution $P(x,y)$, we tightly characterize the complexity of generating $P$ by the psd-rank, a measure recently proposed by Fiorini, Massar, Pokutta, Tiwary and de Wolf (STOC 2012). We also present a characterization of the complexity of generating a general quantum state $\\rho$.

  20. Gamma dosimetry of the uranium deposit in Sao Jose de Espinharas, Paraiba, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Alberto Antonio da, E-mail: alberto.silva@barreiros.ifpe.edu.br [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco (IFPE), Barreiros, PE (Brazil); Santos Junior, Jose Araujo dos; Cunha, Andre Felippe Vieira da; Amaral, Romilton dos Santos; Oliveira, Iane Andrade de; Bezerra, Jairo Dias; Silva, Flavio Ferreira da, E-mail: alberto.silva@barreiros.ifpe.edu.br, E-mail: jaraujo@ufpe.br, E-mail: andre.fvcunha@ufpe.br, E-mail: romilton@ufpe.br, E-mail: jairo.dias@ufpe.br, E-mail: iane_andrade@yahoo.com.br [Universidade Federal de Pernambuco (RAE/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudo sobre Radioecologia

    2013-07-01

    Radioecology studies contribute to the monitoring of both anthropic and natural radionuclides, as well as their correlation with the ecosystem and the population. Terrestrial sources, which mainly include the primary radionuclides of the {sup 238}U, {sup 232}Th, and {sup 40}K series, contribute to a higher effective dose received by humanity, with 84% from terrestrial radionuclides and another 16% derived from cosmogenic nuclides. Areas with high levels of natural radiation, above the acceptable limits, are of great relevance for the development of dosimetry studies, whose core aims include the preservation of the environment and the control of the population's exposure to radiation. The town of Sao Jose de Espinharas, Paraiba, Brazil, has a uranium oxide mine with an average grade of 1,200 mg/kg. In the present study, non-destructive, in situ assays were performed along the entire radiometrically anomalous area. The results obtained in terms of effective doses varied from 3.79 to 93.80 mSv.y{sup -1}, with an average of 19.47 mSv.y{sup -1} thus leading to the conclusion that all of the monitored points presented environmental doses of above the reference value of 2.4 mSv.y{sup -1}, suggesting that both qualitative and quantitative analyses concerning the environmental matrixes in question need to be performed. (author)

  1. Hydroelectric modelling of the Paraiba do Sul and Jequitinhonha rivers sub-basins by using the VALORAGUA computer program; Modelagem hidreletrica das sub bacias dos rios Paraiba do Sul e Jequitinhonha utilizando o programa VALORAGUA

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Vinicius Verna Magalhaes; Aronne, Ivan Dionysio [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil)]. E-mails: vvmf@urano.cdtn.br; aroneid@urano.cdtn.br; Martinez, Carlos Barreira; Versiani, Bruno Rabelo [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Escola de Engenharia. Dept. de Engenharia Hidraulica e Recursos Hidricos]. E-mail: martinez@cce.ufmg.br; versiani@ehr.ufmg.br

    2002-07-01

    This work presents a modelling of 50 hydroelectric power plants in the East Atlantica hydro graphic basin, operating, under construction or as basic projects. The simulations are performed by using the VALORAGUA computer code, developed by the EDP - Eletricidade de Portugal. The studies concentrate mostly on the sub basins of the Jequitinhonha and Paraiba do Sul rivers. The study includes the thermal power plants existent on the same geographical region. Some obtained results such as capacity factors and energy generation values are analysed. Some considerations are made on questions referring to the Brazilian energetic problems.

  2. Morbidade da esquistossomose mansoni no Brasil: II - Estudo em quatro áreas de campo nos Estados de Minas Gerais, Sergipe e Paraíba Morbidity of schistosomiasis mansoni in Brazil: II - Study in 4 field areas in the states of Minas Gerais, Sergipe and Paraiba

    Directory of Open Access Journals (Sweden)

    J. Rodrigues Coura

    1983-03-01

    , and Padre Paraíso, both in Minas Gerais State and two others in the Northeast Region (Riachuelo, Sergipe State and Alhandra, Paraíba State. The total sample studied in the four areas was 4,870, divided as follows: Capitão Andrade (area1 - 1,369; Riachuelo (area 2 - 850; Padre Paraíso (area 3 - 1,736; and Alhandra (area 4 - 915. In area 1, with a total population of 1,480 inhabitants, a study of the entire population was attempted. In areas 2, 3, and 4, due to the large number of inhabitants, a systematic sample by conglomerates was studied, of approximately 25 per cent of the population (family grouping of one in every four residences. The study consisted of an evaluation of the economic and sanitary conditions of the population, of contact with the local foci of transmission of schistosomiasis, of the frequency and intensity of infection by S. mansoni and of the relation between parasite load and the different clinical forms of the disease in different age groups. In parallel, a study was carried out of the intermediate hosts in each area and of the frequency of infection with S. mansoni cercariae. The prevalence of active S. mansoni infection was 60.8, 50.5, 63.1 and 46.6 per cent in areas 1, 2, 3 and, with a median egg elimination of 207, 77.6, 391 and 211 per gram, respectively. Progressive increases in frquency of infection of parasite load and of serious forms of the disease were observed from the first to the third decade in the areas of the Southeast Region and a later increase in the same parameters in the Northeast Region. Other correlations between clinical forms of the disease and age groups, sex, and ethnical origins of the patients, as well as frequency among the planorbids, were carried out.

  3. Análise da infra-estrutura existente em unidades de produção agrícola para processamento de mel na região do Vale do Paraíba-SP Analysis of production unit infrastructure of honey processing agricultural in the Paraiba Valley, São Paulo state-Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Eugênio Veneziani Pasin

    2008-04-01

    Full Text Available Objetivou-se neste trabalho analisar a existência de infra-estrutura para processamento de mel, em Unidades de Produção Agrícola-UPAs na região do Vale do Paraíba-SP. Para a realização desse trabalho utilizou-se o método de levantamento dos dados primários através de questionário. No período de janeiro de 2005 a março de 2006 realizou-se o trabalho com a amostra de 116 UPAs, que representam 33,7% do total de unidades onde há atividade apícola. Para avaliar-se a associação e a relação de dependência entre as variáveis equipamentos, casa do mel, escolaridade, tempo na atividade e número de colméias na UPA, utilizou-se o teste do qui-quadrado X² . Os resultados revelaram que a centrífuga está presente em 58,6% das UPAs e a casa do mel em 29,3% das UPAs das unidades da região. O nível de escolaridade, tempo de permanência do apicultor na atividade e o número de colméias são variáveis que estabelecem relações significativas com a existência de centrífuga e de casa do mel na UPA.The aim of this paper is to analyze the infrastructure for honey process in Agricultural Production Units (UPAs located in the Paraíba Valley (São Paulo state, Brazil. For this study to be carried out, the search of primary data method using a questionnaire was applied. From January 2005 to March 2006, 116 UPAs samples, representing 33.7% of all bee-related UPAs were used. For the association and relation of dependence among the equipment variables, "casa do mel", staff education level, time in the activity and number of bee-hives in the UPA, the chi-square (X² statistical tests were applied. The results revealed that centrifuges were present in 58.6% of UPAs, while the type of "casa do mel" occured in 29.3% of UPAs in the region. The staff education level, time in the activity and number of bee-hives are variables which are important when considering the existence of centrifuges and "casa do mel" in the UPA.

  4. Análise físico-química dos méis das abelhas Apis mellifera e Melipona scutellaris produzidos em regiões distintas no Estado da Paraíba Physical-Chemical analysis of honeybee Apis mellifera and Melipona scutellaris on two regions at Paraiba State, Brazil

    Directory of Open Access Journals (Sweden)

    Adriana Evangelista-Rodrigues

    2005-10-01

    determination its quality for commercialization. The objective of this work was the physical-chemical analysis of honeybee Apis mellifera and Melipona scutellaris to Brejo and Cariri (Paraíba State Brazil. With the gotten results, it was observed that the honeybee M. scutellaris presents a bigger water text (25.25% humidity when compared with the honeybee A. mellifera (18.76%, making difficult its storage, with lower time of shelf life. It had, as reply to the hidroximetilfurfural analyses, higher value for the honey produced in the Cariri when compared with the honey produced in the Brejo, what it can be explained by the difference temperature, of being higher in the Cariri. For the pH values was made as to the significance of the differences between the honeys was gotten, with the honey of the Cariri presenting lower value (3.8. For Total Acidity, the honeybee A. mellifera of the Brejo presented 41.6 meq/kg of honey, while the native honey presented 28.3 meq/kg of honey. For the too much studied parameters it didn't have significant difference between the group. As conclusion the analytical results on the honeys produced indicate a good level of quality both A.mellifera and M. scutellaris. The parameters indicatiing a shelf life of the product were most satisfactory.

  5. Entropy Concept for Paramacrosystems with Complex States

    Directory of Open Access Journals (Sweden)

    Yuri S. Popkov

    2012-05-01

    Full Text Available Consideration is given to macrosystems called paramacrosystems with states of finite capacity and distinguishable and undistinguishable elements with stochastic behavior. The paramacrosystems fill a gap between Fermi and Einstein macrosystems. Using the method of the generating functions, we have obtained expressions for probabilistic characteristics (distribution of the macrostate probabilities, physical and information entropies of the paramacrosystems. The cases with equal and unequal prior probabilities for elements to occupy the states with finite capacities are considered. The unequal prior probabilities influence the morphological properties of the entropy functions and the functions of the macrostate probabilities, transforming them in the multimodal functions. The examples of the paramacrosystems with two-modal functions of the entropy and distribution of the macrostate probabilities are presented. The variation principle does not work for such cases.

  6. The use of handheld radiometry for the identification of stratigraphic characteristics of Paraiba Basin units; A aplicacao da radiometria autoportada na identificacao de caracteristicas estratigraficas nas unidades da Bacia Paraiba

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Ebenezer Moreno de; Villar, Heldio Pereira; Lima, Ricardo de Andrade [Centro Regional de Ciencias Nucleares (CRCN), Recife, PE (Brazil); Lima Filho, Mario [Pernambuco Univ., Recife, PE (Brazil). Dept. de Geologia

    2000-07-01

    A study on the use of radiometric techniques for the identification of stratigraphic characteristics of Paraiba Basin units was carried out with handheld instrumentation. The area chosen ran from north Pernambuco to south Paraiba. The presence of radioactive material had been previously determined. For this work a portable scintillometer was fixed to the door of a vehicle, on the outside, with the probe directed downwards. Background radiation was measured as 40 cps (counts per second). The scintillometer has an alarm which sounds whenever the measured count rate rises above a pre-established figure, 100 cps in the present case. Monitoring then proceeded manually. In sites where the count rate was much higher than 100 cps, the probe was lowered to the soil surface. Local coordinates were obtained by GPS. Therefore, an isoradioactivity map of the area could be drawn. The comparison between this map and local geological charts showed significant correlation between observed count rates and geologic formations. Low count rates were indicative of the Barreiras formation, whereas the highest rates were obtained for the Gramame formation (with urano-phosphatic lythotypes). It is concluded that handheld radiometry is a useful tool in geological charting, is special in areas where stratigraphic units have been masked by environmental changes and human activities. (author)

  7. Thermodynamic Ground States of Complex Oxide Heterointerfaces

    DEFF Research Database (Denmark)

    Gunkel, F.; Hoffmann-Eifert, S.; Heinen, R. A.

    2017-01-01

    The formation mechanism of 2-dimensional electron gases (2DEGs) at heterointerfaces between nominally insulating oxides is addressed with a thermodynamical approach. We provide a comprehensive analysis of the thermodynamic ground states of various 2DEG systems directly probed in high temperature...... equilibrium conductivity measurements. We unambiguously identify two distinct classes of oxide heterostructures: For epitaxial perovskite/perovskite heterointerfaces (LaAlO3/SrTiO3, NdGaO3/SrTiO3, and (La,Sr)(Al,Ta)O3/SrTiO3), we find the 2DEG formation being based on charge transfer into the interface...

  8. Use of thin layer chromatography for the determination of radiochemical purity of radiopharmaceuticals in nuclear medicine services of Paraiba and Rio Grande do Norte, Brazil; Utilizacao da cromatografia em camada delgada para determinacao da pureza radioquimica de radiofarmacos em servicos de medicina nuclear da Paraiba e Rio Grande do Norte, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, W.G.; Santos, P.A.L.; Lima, F.R.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Programa de Pos-Graduacao em Tecnologia Energetica; Lima, F.F., E-mail: wellington.gandrade@gmail.com [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2012-07-01

    The paper chromatography and the thin layer chromatography are separation techniques in which the radioactive components migrate because of their affinity with the eluent (mobile phase) or stationary phase, respectively. In radiopharmaceuticals labeled with {sup 99m}Tc, besides its own radiopharmaceutical, {sup 99m}TcO{sup 4-} free and TcO{sub 2} can be identified and quantified. The evaluation of radiochemical purity of radiopharmaceuticals is essential to produce images free of artifacts as well as avoid unnecessary absorbed dose to the patient. Once they are managed in humans it is important and necessary that they undergo to strict quality control. Because of this, ANVISA in its 'Resolucao da Diretoria Colegiada (RDC) 38 of June 4th, 2008 states the obligation of performing a minimum of tests in nuclear medicine services routine prior to human administration. This work evaluated, by the method of thin layer chromatography (TLC), radiochemical purity, determined the pH of the radiopharmaceutical DEXTRAN- 500, DMSA, DTPA, PHYTATE, MDP, MIBI and Sn-Col used in nuclear medicine services in the states of Paraiba and Rio Grande do Norte - Brazil. The results show that the use of thin layer chromatography (TLC) as a standard method in routine of nuclear medicine services is possible, because it provides important data for the evaluation of radiochemical purity, allowing the exclusion of a radiopharmaceutical poorly marked. (author)

  9. Reconstructing complex networks with binary-state dynamics

    CERN Document Server

    Li, Jingwen; Lai, Ying-Cheng; Grebogi, Celso

    2015-01-01

    The prerequisite for our understanding of many complex networked systems lies in the reconstruction of network structure from measurable data. Although binary-state dynamics occurring in a broad class of complex networked systems in nature and society and has been intensively investigated, a general framework for reconstructing complex networks from binary states, the inverse problem, is lacking. Here we offer a general solution to the reconstruction problem by developing a data-based linearization approach for binary-state dynamics with linear, nonlinear, discrete and stochastic switching functions. The linearization allows us to convert the network reconstruction problem into a sparse signal reconstruction problem that can be resolved efficiently and credibly by convex optimization based on compressed sensing. The completely data-based linearization method and the sparse signal reconstruction constitutes a general framework for reconstructing complex networks without any knowledge of the binary-state dynami...

  10. Ultrafast laser spectroscopy in complex solid state materials

    Energy Technology Data Exchange (ETDEWEB)

    Li, Tianqi [Iowa State Univ., Ames, IA (United States)

    2014-12-01

    This thesis summarizes my work on applying the ultrafast laser spectroscopy to the complex solid state materials. It shows that the ultrafast laser pulse can coherently control the material properties in the femtosecond time scale. And the ultrafast laser spectroscopy can be employed as a dynamical method for revealing the fundamental physical problems in the complex material systems.

  11. Complexity and state-transitions in social dependence networks

    Directory of Open Access Journals (Sweden)

    Giuliano Pistolesi

    2001-01-01

    Full Text Available Computation of complexity in Social Dependence Networks is an interesting research domain to understand evolution processes and group exchange dynamics in natural and artificial intelligent Multi-Agent Systems. We perform an agent-based simulation by NET-PLEX (Conte and Pistolesi, 2000, a new software system able both to build interdependence networks tipically emerging in Multi-Agent System scenarios and to investigate complexity phenomena, i.e., unstability and state-transitions like Hopf bifurcation (Nowak and Lewenstein, 1994, and to describe social self organization phenomena emerging in these artificial social systems by means of complexity measures similar to those introduced by Hubermann and Hogg (1986. By performing analysis of complexity in these kind of artificial societies we observed interesting phenomena in emerging organizations that suggest state-transitions induced by critical configurations of parameters describing the social system similar to those observed in many studies on state-transitions in bifurcation chaos (Schuster, 1988; Ruelle, 1989.

  12. Finite-State Complexity and the Size of Transducers

    Directory of Open Access Journals (Sweden)

    Cristian Calude

    2010-08-01

    Full Text Available Finite-state complexity is a variant of algorithmic information theory obtained by replacing Turing machines with finite transducers. We consider the state-size of transducers needed for minimal descriptions of arbitrary strings and, as our main result, we show that the state-size hierarchy with respect to a standard encoding is infinite. We consider also hierarchies yielded by more general computable encodings.

  13. Direct observation of photoinduced bent nitrosyl excited-state complexes

    Energy Technology Data Exchange (ETDEWEB)

    Sawyer, Karma R.; Steele, Ryan P.; Glascoe, Elizabeth A.; Cahoon, James F.; Schlegel, Jacob P.; Head-Gordon, Martin; Harris, Charles B.

    2008-06-28

    Ground state structures with side-on nitrosyl ({eta}{sup 2}-NO) and isonitrosyl (ON) ligands have been observed in a variety of transition-metal complexes. In contrast, excited state structures with bent-NO ligands have been proposed for years but never directly observed. Here we use picosecond time-resolved infrared spectroscopy and density functional theory (DFT) modeling to study the photochemistry of Co(CO){sub 3}(NO), a model transition-metal-NO compound. Surprisingly, we have observed no evidence for ON and {eta}{sup 2}-NO structural isomers, but have observed two bent-NO complexes. DFT modeling of the ground and excited state potentials indicates that the bent-NO complexes correspond to triplet excited states. Photolysis of Co(CO){sub 3}(NO) with a 400-nm pump pulse leads to population of a manifold of excited states which decay to form an excited state triplet bent-NO complex within 1 ps. This structure relaxes to the ground triplet state in ca. 350 ps to form a second bent-NO structure.

  14. Chimaera simulation of complex states of flowing matter

    Science.gov (United States)

    Succi, S.

    2016-11-01

    We discuss a unified mesoscale framework (chimaera) for the simulation of complex states of flowing matter across scales of motion. The chimaera framework can deal with each of the three macro-meso-micro levels through suitable `mutations' of the basic mesoscale formulation. The idea is illustrated through selected simulations of complex micro- and nanoscale flows. This article is part of the themed issue 'Multiscale modelling at the physics-chemistry-biology interface'.

  15. Efficient growth of complex graph states via imperfect path erasure

    CERN Document Server

    Campbell, E T; Fitzsimons, J; Kok, P; Benjamin, Simon C.; Campbell, Earl T.; Fitzsimons, Joseph; Kok, Pieter

    2007-01-01

    Given a suitably large and well connected (complex) graph state, any quantum algorithm can be implemented purely through local measurements on the individual qubits. Measurements can also be used to create the graph state: Path erasure techniques allow one to entangle multiple qubits by determining only global properties of the qubits. Here, this powerful approach is extended by demonstrating that even imperfect path erasure can produce the required graph states with high efficiency. By characterizing the degree of error in each path erasure attempt, one can subsume the resulting imperfect entanglement into an extended graph state formalism. The subsequent growth of the improper graph state can be guided, through a series of strategic decisions, in such a way as to bound the growth of the error and eventually yield a high-fidelity graph state. As an implementation of these techniques, we develop an analytic model for atom (or atom-like) qubits in mismatched cavities, under the double-heralding entanglement pr...

  16. The State – Nation Imbalance. Peace and Complex Circumstances

    Directory of Open Access Journals (Sweden)

    Cristian - Sorin Prună

    2012-12-01

    Full Text Available The defining reference points of this paper take into consideration the creation of severalscientific premises which would structure the approached issue-constitutional state (nationcorrelated with the term security–by reference to the current international context coordinates. Thegoal of the proposed approach is organizing the elements which define the security of theconstitutional state from the perspective of the coexistence between peace and complex situations(crisis and war. In the effort of organizing such a scientific matter, we attempted to realize clear,concise boundaries by means of research–the study and analysis of conflicting phenomena(conclusive factors / consequences. Thus, we pointed out the role of the modern constitutional statein the current context, theinference between the state–nation balance, through its components, topreserve peace and nation security through efficient management of complex situations.

  17. Complex network analysis of state spaces for random Boolean networks

    Energy Technology Data Exchange (ETDEWEB)

    Shreim, Amer [Complexity Science Group, Department of Physics and Astronomy, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Berdahl, Andrew [Complexity Science Group, Department of Physics and Astronomy, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Sood, Vishal [Complexity Science Group, Department of Physics and Astronomy, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Grassberger, Peter [Complexity Science Group, Department of Physics and Astronomy, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Paczuski, Maya [Complexity Science Group, Department of Physics and Astronomy, University of Calgary, Calgary, AB, T2N 1N4 (Canada)

    2008-01-15

    We apply complex network analysis to the state spaces of random Boolean networks (RBNs). An RBN contains N Boolean elements each with K inputs. A directed state space network (SSN) is constructed by linking each dynamical state, represented as a node, to its temporal successor. We study the heterogeneity of these SSNs at both local and global scales, as well as sample to-sample fluctuations within an ensemble of SSNs. We use in-degrees of nodes as a local topological measure, and the path diversity (Shreim A et al 2007 Phys. Rev. Lett. 98 198701) of an SSN as a global topological measure. RBNs with 2 {<=} K {<=} 5 exhibit non-trivial fluctuations at both local and global scales, while K = 2 exhibits the largest sample-to-sample (possibly non-self-averaging) fluctuations. We interpret the observed 'multi scale' fluctuations in the SSNs as indicative of the criticality and complexity of K = 2 RBNs. 'Garden of Eden' (GoE) states are nodes on an SSN that have in-degree zero. While in-degrees of non-GoE nodes for K > 1 SSNs can assume any integer value between 0 and 2{sup N}, for K = 1 all the non-GoE nodes in a given SSN have the same in-degree which is always a power of two.

  18. Distinguishability of quantum states and shannon complexity in quantum cryptography

    Science.gov (United States)

    Arbekov, I. M.; Molotkov, S. N.

    2017-07-01

    The proof of the security of quantum key distribution is a rather complex problem. Security is defined in terms different from the requirements imposed on keys in classical cryptography. In quantum cryptography, the security of keys is expressed in terms of the closeness of the quantum state of an eavesdropper after key distribution to an ideal quantum state that is uncorrelated to the key of legitimate users. A metric of closeness between two quantum states is given by the trace metric. In classical cryptography, the security of keys is understood in terms of, say, the complexity of key search in the presence of side information. In quantum cryptography, side information for the eavesdropper is given by the whole volume of information on keys obtained from both quantum and classical channels. The fact that the mathematical apparatuses used in the proof of key security in classical and quantum cryptography are essentially different leads to misunderstanding and emotional discussions [1]. Therefore, one should be able to answer the question of how different cryptographic robustness criteria are related to each other. In the present study, it is shown that there is a direct relationship between the security criterion in quantum cryptography, which is based on the trace distance determining the distinguishability of quantum states, and the criterion in classical cryptography, which uses guesswork on the determination of a key in the presence of side information.

  19. Control of State Transitions in Complex and Biophysical Networks

    Science.gov (United States)

    Motter, Adilson; Wells, Daniel; Kath, William

    Noise is a fundamental part of intracellular processes. While the response of biological systems to noise has been studied extensively, there has been limited understanding of how to exploit it to induce a desired cell state. Here I will present a scalable, quantitative method based on the Freidlin-Wentzell action to predict and control noise-induced switching between different states in genetic networks that, conveniently, can also control transitions between stable states in the absence of noise. I will discuss applications of this methodology to predict control interventions that can induce lineage changes and to identify new candidate strategies for cancer therapy. This framework offers a systems approach to identifying the key factors for rationally manipulating network dynamics, and should also find use in controlling other classes of complex networks exhibiting multi-stability. Reference: D. K. Wells, W. L. Kath, and A. E. Motter, Phys. Rev. X 5, 031036 (2015). Work funded by CBC, NCI, NIGMS, and NSF.

  20. State analysis requirements database for engineering complex embedded systems

    Science.gov (United States)

    Bennett, Matthew B.; Rasmussen, Robert D.; Ingham, Michel D.

    2004-01-01

    It has become clear that spacecraft system complexity is reaching a threshold where customary methods of control are no longer affordable or sufficiently reliable. At the heart of this problem are the conventional approaches to systems and software engineering based on subsystem-level functional decomposition, which fail to scale in the tangled web of interactions typically encountered in complex spacecraft designs. Furthermore, there is a fundamental gap between the requirements on software specified by systems engineers and the implementation of these requirements by software engineers. Software engineers must perform the translation of requirements into software code, hoping to accurately capture the systems engineer's understanding of the system behavior, which is not always explicitly specified. This gap opens up the possibility for misinterpretation of the systems engineer's intent, potentially leading to software errors. This problem is addressed by a systems engineering tool called the State Analysis Database, which provides a tool for capturing system and software requirements in the form of explicit models. This paper describes how requirements for complex aerospace systems can be developed using the State Analysis Database.

  1. State analysis requirements database for engineering complex embedded systems

    Science.gov (United States)

    Bennett, Matthew B.; Rasmussen, Robert D.; Ingham, Michel D.

    2004-01-01

    It has become clear that spacecraft system complexity is reaching a threshold where customary methods of control are no longer affordable or sufficiently reliable. At the heart of this problem are the conventional approaches to systems and software engineering based on subsystem-level functional decomposition, which fail to scale in the tangled web of interactions typically encountered in complex spacecraft designs. Furthermore, there is a fundamental gap between the requirements on software specified by systems engineers and the implementation of these requirements by software engineers. Software engineers must perform the translation of requirements into software code, hoping to accurately capture the systems engineer's understanding of the system behavior, which is not always explicitly specified. This gap opens up the possibility for misinterpretation of the systems engineer's intent, potentially leading to software errors. This problem is addressed by a systems engineering tool called the State Analysis Database, which provides a tool for capturing system and software requirements in the form of explicit models. This paper describes how requirements for complex aerospace systems can be developed using the State Analysis Database.

  2. Nucleotide Docking: Prediction of Reactant State Complexes for Ribonuclease Enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Elsasser, Brigitta M.; Fels, Gregor

    2010-12-01

    Ribonuclease enzymes (RNases) play key roles in the maturation and metabolism of all RNA molecules. Computational simulations of the processes involved can help to elucidate the underlying enzymatic mechanism and is often employed in a synergistic approach together with biochemical experiments. Theoretical calculations require atomistic details regarding the starting geometries of the molecules involved, which, in the absence of crystallographic data, can only be achieved from computational docking studies. Fortunately, docking algorithms have improved tremendously in recent years, so that reliable structures of enzyme-ligand complexes can now be successfully obtained from computation. However, most docking programs are not particularly optimized for nucleotide docking. In order to assist our studies on the cleavage of RNA by the two most important ribonuclease enzymes, RNase A and RNase H, we evaluated four docking tools - MOE2009, Glide 5.5, QXP-Flo+0802, and Autodock 4.0 - for their ability to simulate complexes between these enzymes and RNA oligomers. To validate our results, we analyzed the docking results with respect to the known key interactions between the protein and the nucleotide. In addition, we compared the predicted complexes with X-ray structures of the mutated enzyme as well as with structures obtained from previous calculations. In this manner, we were able to prepare the desired reaction state complex so that it could be used as the starting structure for further DFT/B3LYP QM/MM reaction mechanism studies.

  3. Seasonal variation of particulate heavy metals in the Lower Paraiba do Sul River, R.J., Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, C.E.V. [Universidade Estadual do Norte Fluminense, Horto (Brazil). Lab. de Ciencias Ambientais]|[Universidade Federal Fluminense, Niteroi (Brazil). Dept. de Geoquimica; Ovalle, A.R.C.; Rezende, C.E.; Molisani, M.M.; Salomao, M.S.M.B. [Universidade Estadual do Norte Fluminense, Horto (Brazil). Lab. de Ciencias Ambientais; Lacerda, L.D. [Universidade Federal Fluminense, Niteroi (Brazil). Dept. de Geoquimica

    1999-04-01

    Temporal and spatial variability of particulate metal concentrations (Cu, Cr, Zn, Mn and Fe) were investigated in the lower drainage basin of the Paraiba do Sul River. The results showed that the spatial variability was not important for all the studied metals, however, temporal variations seems to be considerable. In general, two distinct behaviors were observed for particulate heavy metals: (1) metal concentration increase together with water flow (Fe and Cu) and (2) concentration decrease with increasing water flux (Zn, Cr and Mn). The Fe and Cu behavior is probably due to the strong association of these metals with surface runoff, although their sources seem to be distinct. Iron probably originates from the regional soils rich in iron oxides, and Cu is possibly associated to the large-scale use of copper fungicides in the sugar cane plantations. The opposite trend observed for Zn, Cr and Mn probably reflects the importance of the industrial and urban effluents as a secondary source of these elements for the system. Their behavior is probably associated with the dilution effect caused by the input of a suspended matter poor in these metals originated from the surface runoff during the rainy season. (orig.)

  4. Understanding and controlling complex states arising from magnetic frustration

    Energy Technology Data Exchange (ETDEWEB)

    Zapf, Vivien [Los Alamos National Laboratory

    2012-06-01

    Much of our national security relies on capabilities made possible by magnetism, in particular the ability to compute and store huge bodies of information as well as to move things and sense the world. Most of these technologies exploit ferromagnetism, i.e. the global parallel alignment of magnetic spins as seen in a bar magnet. Recent advances in computing technologies, such as spintronics and MRAM, take advantage of antiferromagnetism where the magnetic spins alternate from one to the next. In certain crystal structures, however, the spins take on even more complex arrangements. These are often created by frustration, where the interactions between spins cannot be satisfied locally or globally within the material resulting in complex and often non-coplanar spin textures. Frustration also leads to the close proximity of many different magnetic states, which can be selected by small perturbations in parameters like magnetic fields, temperature and pressure. It is this tunability that makes frustrated systems fundamentally interesting and highly desirable for applications. We move beyond frustration in insulators to itinerant systems where the interaction between mobile electrons and the non-coplanar magnetic states lead to quantum magneto-electric amplification. Here a small external field is amplified by many orders of magnitude by non-coplanar frustrated states. This greatly enhances their sensitivity and opens broader fields for applications. Our objective is to pioneer a new direction for condensed matter science at the Laboratory as well as for international community by discovering, understanding and controlling states that emerge from the coupling of itinerant charges to frustrated spin textures.

  5. Transition state ensemble optimization for reactions of arbitrary complexity

    Science.gov (United States)

    Zinovjev, Kirill; Tuñón, Iñaki

    2015-10-01

    In the present work, we use Variational Transition State Theory (VTST) to develop a practical method for transition state ensemble optimization by looking for an optimal hyperplanar dividing surface in a space of meaningful trial collective variables. These might be interatomic distances, angles, electrostatic potentials, etc. Restrained molecular dynamics simulations are used to obtain on-the-fly estimates of ensemble averages that guide the variations of the hyperplane maximizing the transmission coefficient. A central result of our work is an expression that quantitatively estimates the importance of the coordinates used for the localization of the transition state ensemble. Starting from an arbitrarily large set of trial coordinates, one can distinguish those that are indeed essential for the advance of the reaction. This facilitates the use of VTST as a practical theory to study reaction mechanisms of complex processes. The technique was applied to the reaction catalyzed by an isochorismate pyruvate lyase. This reaction involves two simultaneous chemical steps and has a shallow transition state region, making it challenging to define a good reaction coordinate. Nevertheless, the hyperplanar transition state optimized in the space of 18 geometrical coordinates provides a transmission coefficient of 0.8 and a committor histogram well-peaked about 0.5, proving the strength of the method. We have also tested the approach with the study of the NaCl dissociation in aqueous solution, a stringest test for a method based on transition state theory. We were able to find essential degrees of freedom consistent with the previous studies and to improve the transmission coefficient with respect to the value obtained using solely the NaCl distance as the reaction coordinate.

  6. Response to Disturbance and Abundance of Final State: a Measure for Complexity?

    Institute of Scientific and Technical Information of China (English)

    SHEN Dan; WANG Wen-Xiu; JIANG Yu-Mei; HE Yue; HE Da-Ren

    2007-01-01

    We propose a new definition of complexity. The definition shows that when a system evolves to a final state via a transient state, its complexity depends on the abundance of both the final state and transient state. The abundance of the transient state may be described by the diversity of the response to disturbance. We hope that this definition can describe a clear boundary between simple systems and complex systems by showing that all the simple systems have zero complexity, and all the complex systems have positive complexity. Some examples of the complexity calculations are presented, which supports our hope.

  7. Hydroxyl radical reactions with adenine: reactant complexes, transition states, and product complexes.

    Science.gov (United States)

    Cheng, Qianyi; Gu, Jiande; Compaan, Katherine R; Schaefer, Henry F

    2010-10-18

    In order to address problems such as aging, cell death, and cancer, it is important to understand the mechanisms behind reactions causing DNA damage. One specific reaction implicated in DNA oxidative damage is hydroxyl free-radical attack on adenine (A) and other nucleic acid bases. The adenine reaction has been studied experimentally, but there are few theoretical results. In the present study, adenine dehydrogenation at various sites, and the potential-energy surfaces for these reactions, are investigated theoretically. Four reactant complexes [A···OH]* have been found, with binding energies relative to A+OH* of 32.8, 11.4, 10.7, and 10.1 kcal mol(-1). These four reactant complexes lead to six transition states, which in turn lie +4.3, -5.4, (-3.7 and +0.8), and (-2.3 and +0.8) kcal mol(-1) below A+OH*, respectively. Thus the lowest lying [A···OH]* complex faces the highest local barrier to formation of the product (A-H)*+H(2)O. Between the transition states and the products lie six product complexes. Adopting the same order as the reactant complexes, the product complexes [(A-H)···H(2)O]* lie at -10.9, -22.4, (-24.2 and -18.7), and (-20.5 and -17.5) kcal mol(-1), respectively, again relative to separated A+OH*. All six A+OH* → (A-H)*+H(2)O pathways are exothermic, by -0.3, -14.7, (-17.4 and -7.8), and (-13.7 and -7.8) kcal mol(-1), respectively. The transition state for dehydrogenation at N(6) lies at the lowest energy (-5.4 kcal mol(-1) relative to A+OH*), and thus reaction is likely to occur at this site. This theoretical prediction dovetails with the observed high reactivity of OH radicals with the NH(2) group of aromatic amines. However, the high barrier (37.1 kcal mol(-1)) for reaction at the C(8) site makes C(8) dehydrogenation unlikely. This last result is consistent with experimental observation of the imidazole ring opening upon OH radical addition to C(8). In addition, TD-DFT computed electronic transitions of the N(6) product around 420 nm

  8. Complex Analysis of Financial State and Performance of Construction Enterprises

    Directory of Open Access Journals (Sweden)

    Algirdas Krivka

    2015-12-01

    Full Text Available The paper analyses the financial state and performance of large constructions enterprises by applying financial indicators. As there is no one single decisive financial indicator enabling to objectively assess enterprise performance, the multi-criteria decision making (MCDM methods are applied with four groups of financial ratios (profitability, liquidity, solvency and asset turnover acting as evaluation criteria, while the alternatives assessed are two enterprises compared throughout the reference period of three years, also with the average indicator values of the whole construction sector. The weights of the criteria have been estimated by involving competent experts with chi-square test employed to check the degree of agreement of expert estimates. The research methodology contributes to the issue of complex evaluation of enterprise financial state and performance, while the result of the multi-criteria assessment – the ranking of enterprises and sector average with respect to financial state and performance – could be considered worth attention from business owners, potential investors, customers or other possible stakeholders.

  9. Solid state photosensitive devices which employ isolated photosynthetic complexes

    Science.gov (United States)

    Peumans, Peter; Forrest, Stephen R.

    2009-09-22

    Solid state photosensitive devices including photovoltaic devices are provided which comprise a first electrode and a second electrode in superposed relation; and at least one isolated Light Harvesting Complex (LHC) between the electrodes. Preferred photosensitive devices comprise an electron transport layer formed of a first photoconductive organic semiconductor material, adjacent to the LHC, disposed between the first electrode and the LHC; and a hole transport layer formed of a second photoconductive organic semiconductor material, adjacent to the LHC, disposed between the second electrode and the LHC. Solid state photosensitive devices of the present invention may comprise at least one additional layer of photoconductive organic semiconductor material disposed between the first electrode and the electron transport layer; and at least one additional layer of photoconductive organic semiconductor material, disposed between the second electrode and the hole transport layer. Methods of generating photocurrent are provided which comprise exposing a photovoltaic device of the present invention to light. Electronic devices are provided which comprise a solid state photosensitive device of the present invention.

  10. Computational complexity of nonequilibrium steady states of quantum spin chains

    Science.gov (United States)

    Marzolino, Ugo; Prosen, Tomaž

    2016-03-01

    We study nonequilibrium steady states (NESS) of spin chains with boundary Markovian dissipation from the computational complexity point of view. We focus on X X chains whose NESS are matrix product operators, i.e., with coefficients of a tensor operator basis described by transition amplitudes in an auxiliary space. Encoding quantum algorithms in the auxiliary space, we show that estimating expectations of operators, being local in the sense that each acts on disjoint sets of few spins covering all the system, provides the answers of problems at least as hard as, and believed by many computer scientists to be much harder than, those solved by quantum computers. We draw conclusions on the hardness of the above estimations.

  11. Steady-state distributions of probability fluxes on complex networks

    Science.gov (United States)

    Chełminiak, Przemysław; Kurzyński, Michał

    2017-02-01

    We consider a simple model of the Markovian stochastic dynamics on complex networks to examine the statistical properties of the probability fluxes. The additional transition, called hereafter a gate, powered by the external constant force breaks a detailed balance in the network. We argue, using a theoretical approach and numerical simulations, that the stationary distributions of the probability fluxes emergent under such conditions converge to the Gaussian distribution. By virtue of the stationary fluctuation theorem, its standard deviation depends directly on the square root of the mean flux. In turn, the nonlinear relation between the mean flux and the external force, which provides the key result of the present study, allows us to calculate the two parameters that entirely characterize the Gaussian distribution of the probability fluxes both close to as well as far from the equilibrium state. Also, the other effects that modify these parameters, such as the addition of shortcuts to the tree-like network, the extension and configuration of the gate and a change in the network size studied by means of computer simulations are widely discussed in terms of the rigorous theoretical predictions.

  12. Adubação mineral da batatinha. II - Vale do Paraíba Mineral fertilization of potatoes II - Paraiba Valley

    Directory of Open Access Journals (Sweden)

    H. Gargantini

    1965-01-01

    Full Text Available Em 1962 realizaram-se nove experiências de adubação da batatinha (Solanum tuberosum L. em solos de várzeas do Rio Paraíba, onde a cultura é feita no inverno e com irrigação. Num esquema fatorial 3³, empregaram-se 0, 60, 120 kg/ha de N (sulfato de amônio, 0, 80, 160 kg/ha de P2O5. (superfosfato simples e 0, 45, 90 kg/ha de K2O (sulfato de potássio. O fósforo, o potássio e 1/3 das doses de nitrogênio foram aplicados na ocasião do plantio; os 2/3 restantes das de nitrogênio, em cobertura, antes da amontoa. Em média das sete experiências que puderam ser analisadas conjuntamente, os efeitos lineares dos três nutrientes foram positivos, mas sòmente os do nitrogênio e do fósforo foram significativos. As interações entre nutrientes não alcançaram significância, mas as respostas ao nitrogênio, ao fósforo e ao potássio foram bem maiores quando se empregou cada elemento na presença dos outros dois. Neste caso, os efeitos das doses 1 e 2de nitrogênio corresponderam a +3,36 e +3,62 t/ha (+36 e +39%; de fósforo, a +1,76 e +3,85 t/ha ( + 18 e +39%; de potássio, a +0,72 e +1,89 t/ha (+6 e +16%. Uma das duas experiências excluídas da análise conjunta foi prejudicada nos «stands». Na outra, porém, os três elementos aumentaram significativamente a produção, destacando-se o efeito do fósforo, que atingiu, em média das duas doses, +7,57 t/ha (+354%. Esta experiência foi instalada em solo nunca adubado, ao passo que as demais o foram em áreas que haviam recebido, nas culturas anteriores, duas ou mais aplicações de NPK.Nine experiments with potatoes were conducted in 1962 on the lowlands of the Paraiba Valley, State of São Paulo, where they are planted during the dry period (winter and irrigated by the subsurface method. In those experiment were studied, in a 3³ factorial scheme, increasing rates of application of nitrogen, phosphorus, and potassium. Averaging the seven experiments that could be analysed jointly, the

  13. Study of the environmental degradation of Bodocongó Reservoir in Campina Grande, State of Paraiba, Brasil.

    Directory of Open Access Journals (Sweden)

    Dany Geraldo Kramer Cavalcanti e Silva

    2009-08-01

    Full Text Available Nowadays the environmental resources has been suffering intense transformations impelled by the urbanization and industrial development, through the installation of industries and construction of homes, facts that can endanger the sustainability of any ecosystem. This work had as objective to diagnose the degradation processes practiced along the Bodocongó reservoir and to monitor the quality of the water of this reservoir. For this purpose were used: geoprocessing, digital analysis of images, photographic registrations, field visits. The results showed an absence of administration polices and, in this way a system for the management should be implanted for containing the environmental degradation and prevent the pollution in this aquatic ecosystem.Key-words: environmental degradation, water resource, pollution.

  14. Ground-state and excited-state structures of tungsten-benzylidyne complexes

    Energy Technology Data Exchange (ETDEWEB)

    Lovaasen, B. M.; Lockard, J. V.; Cohen, B. W.; Yang, S.; Zhang, X.; Simpson, C. K.; Chen, L. X.; Hopkins, M. D. (Chemical Sciences and Engineering Division); ( XSD); (The Univ. of Chicago)

    2012-01-01

    The molecular structure of the tungsten-benzylidyne complex trans-W({triple_bond}CPh)(dppe){sub 2}Cl (1; dppe = 1,2-bis(diphenylphosphino)ethane) in the singlet (d{sub xy}){sup 2} ground state and luminescent triplet (d{sub xy}){sup 1}({pi}*(WCPh)){sup 1} excited state (1*) has been studied using X-ray transient absorption spectroscopy, X-ray crystallography, and density functional theory (DFT) calculations. Molecular-orbital considerations suggest that the W-C and W-P bond lengths should increase in the excited state because of the reduction of the formal W-C bond order and decrease in W {yields} P {pi}-backbonding, respectively, between 1 and 1*. This latter conclusion is supported by comparisons among the W-P bond lengths obtained from the X-ray crystal structures of 1, (d{sub xy}){sup 1}-configured 1{sup +}, and (d{sub xy}){sup 2} [W(CPh)(dppe){sub 2}(NCMe)]{sup +} (2{sup +}). X-ray transient absorption spectroscopic measurements of the excited-state structure of 1* reveal that the W-C bond length is the same (within experimental error) as that determined by X-ray crystallography for the ground state 1, while the average W-P/W-Cl distance increases by 0.04 {angstrom} in the excited state. The small excited-state elongation of the W-C bond relative to the M-E distortions found for M({triple_bond}E)L{sub n} (E = O, N) compounds with analogous (d{sub xy}){sup 1}({pi}*(ME)){sup 1} excited states is due to the {pi} conjugation within the WCPh unit, which lessens the local W-C {pi}-antibonding character of the {pi}*(WCPh) lowest unoccupied molecular orbital (LUMO). These conclusions are supported by DFT calculations on 1 and 1*. The similar core bond distances of 1, 1{sup +}, and 1* indicates that the inner-sphere reorganization energy associated with ground- and excited-state electron-transfer reactions is small.

  15. Strain gradients and melt pathways, Twin Sisters complex, Washington State

    Science.gov (United States)

    Kruckenberg, S. C.; Newman, J.; Tikoff, B.; Toy, V. G.

    2009-12-01

    The Twin Sisters complex in the North Cascades of Washington state is a large (~6 by 16 km), virtually unaltered ultramafic body that provides information about the relationships between the formation of compositional layering, structural fabrics and the formation of inferred melt pathways in naturally deforming peridotites. Compositional layering is largely defined by alternating layers of orthopyroxene-absent dunite (>95% olivine) and orthopyroxene-present (~15% orthopyroxene; ~85% olivine) harzburgite aligned parallel to a roughly N-S striking and steeply dipping foliation. Orthopyroxene- and clinopyroxene-bearing dikes occur throughout the Twin Sisters and crosscut the host dunite and harzburgite layering. Orthopyroxene dikes range in thickness from 1 cm to >1 m and are variably oriented and may be folded. Clinopyroxene-bearing dikes are thinner, more consistently oriented (~N-S), and generally more tabular than the orthopyroxene dikes. In the Twin Sisters, cm- to m-scale zones of porphyroclastic dunite cross-cut the main dunite-harzburgite compositional layering and display a variety of relationships with pyroxene dikes in the region. These porphyroclastic dunite bands locally contain single olivine grains >10 cm and likely represent former pathways of melt migration. Transect mapping along an E-W traverse across the Twin Sisters massif reveals that these inferred melt channels form at various angles relative to the main dunite-harzburgite layering. In the west, porphyroclastic olivine layers form at low angle to the main foliation and compositional layering. These zone form at systematically higher angles across the structural section of the Twin Sisters massif to the east and commonly form conjugate cross-cutting sets at high-angle to the main N-S dunite-harzburgite layering. This change in band angle correlates broadly with changes in the intensity of folding of orthopyroxene-bearing dikes, with more intensely deformed dikes in the west to more planar dikes

  16. Physical dispersion state and fluorescent property of Eu-complex in the Eu-complex/silicon rubber composites

    Institute of Scientific and Technical Information of China (English)

    WEN Shipeng; HU Shui; ZHANG Xiaoping; ZHANG Liqun; LIU Li

    2008-01-01

    The fluorescent complex Eu(TTA)2(Phen)(MA) (HTTA=2-Thenoyltdfluoroacetone, Phen=l,10-phenanthroline, MA=Maleic an-hydrider) was synthesized and characterized with elemental analysis, infrared spectrum (IR), scanning electron microscope (SEM), X-ray Diffraction(XRD), differential scanning calorimetry(DSC), and fluorescent measurement. To explore the effect of different physical disper-sion state of Eu-complex on the fluorescent property of the Eu-complex/silicon rubber composites, various quantities of Eu(TTA)2(phen) (MA) were mixed with silicon rubber (SIR) and peroxide to form uncured composites. These composites were vulcanized to obtain cured Eu-complex/SiR composites at 250 ℃, which was higher than the melting-point of Eu-complex. The SEM, XRD, DSC, and the fluorescent measurement of these composites showed that both the complex molecules dispersed in the silicon rubber during the melting process and the parent Eu-complex particles had positive effects on fluorescent property, whereas the re-crystallized Eu-complex particles and the ggregating complexes formed during the melting-process had negative effects on fluorescent property. For the uncured composites, their fluorescent intensities almost did not change with the increasing amount of Eu-complex. Furthermore, for the composites with small content of Eu-complex, their fluorescent intensities decreased significantly after curing, and this difference in fluorescent intensity became smaller as the content of Eu-complex increases.

  17. Ground State and Excited State Tuning in Ferric Dipyrrin Complexes Promoted by Ancillary Ligand Exchange

    Energy Technology Data Exchange (ETDEWEB)

    Kleinlein, Claudia; Zheng, Shao-Liang; Betley, Theodore A.

    2017-04-24

    Three ferric dipyrromethene complexes featuring different ancillary ligands were synthesized by one electron oxidation of ferrous precursors. Four-coordinate iron complexes of the type (ArL)FeX2 [ArL = 1,9-(2,4,6-Ph3C6H2)2-5-mesityldipyrromethene] with X = Cl or tBuO were prepared and found to be high-spin (S = 5/2), as determined by superconducting quantum interference device magnetometry, electron paramagnetic resonance, and 57Fe Mössbauer spectroscopy. The ancillary ligand substitution was found to affect both ground state and excited properties of the ferric complexes examined. While each ferric complex displays reversible reduction and oxidation events, each alkoxide for chloride substitution results in a nearly 600 mV cathodic shift of the FeIII/II couple. The oxidation event remains largely unaffected by the ancillary ligand substitution and is likely dipyrrin-centered. While the alkoxide substituted ferric species largely retain the color of their ferrous precursors, characteristic of dipyrrin-based ligand-to-ligand charge transfer (LLCT), the dichloride ferric complex loses the prominent dipyrrin chromophore, taking on a deep green color. Time-dependent density functional theory analyses indicate the weaker-field chloride ligands allow substantial configuration mixing of ligand-to-metal charge transfer into the LLCT bands, giving rise to the color changes observed. Furthermore, the higher degree of covalency between the alkoxide ferric centers is manifest in the observed reactivity. Delocalization of spin density onto the tert-butoxide ligand in (ArL)FeCl(OtBu) is evidenced by hydrogen atom abstraction to yield (ArL)FeCl and HOtBu in the presence of substrates containing weak C–H bonds, whereas the chloride (ArL)FeCl2 analogue does not react under these conditions.

  18. A Two-Party Probabilistic Communication Complexity Scenario via Werner States

    Institute of Scientific and Technical Information of China (English)

    XUE Peng; LI Chuan-Feng; GUO Guang-Can

    2001-01-01

    We propose a probabilistic two-party communication complexity scenario with a prior Werner state and analyse the communication abilities of quantum correlations (entanglements) and classical correlations. This process can be used as an entanglement monotone of Werner states.

  19. Complexity in Simplicity: Flexible Agent-based State Space Exploration

    DEFF Research Database (Denmark)

    Rasmussen, Jacob Illum; Larsen, Kim Guldstrand

    2007-01-01

    In this paper, we describe a new flexible framework for state space exploration based on cooperating agents. The idea is to let various agents with different search patterns explore the state space individually and communicate information about fruitful subpaths of the search tree to each other...

  20. Complexity in Simplicity: Flexible Agent-based State Space Exploration

    DEFF Research Database (Denmark)

    Rasmussen, Jacob Illum; Larsen, Kim Guldstrand

    2007-01-01

    In this paper, we describe a new flexible framework for state space exploration based on cooperating agents. The idea is to let various agents with different search patterns explore the state space individually and communicate information about fruitful subpaths of the search tree to each other...

  1. Dark excited states of carotenoid in light harvesting complex probing with femtosecond stimulated Raman spectroscopy

    Directory of Open Access Journals (Sweden)

    Sakai S.

    2013-03-01

    Full Text Available Vibrational dynamics of dark excited states in carotenoids have been investigated using tunable Raman pump pulses. The S1 state has same vibrational dynamics in light-harvesting complex (LH1 and solution. The S* state in LH1 has similar vibrational modes with the triplet state of carotenoid. However, the so-called S* state in solution does not have the modes and is concluded to be different from the S* state in LH1.

  2. Topologically protected midgap states in complex photonic lattices

    CERN Document Server

    Schomerus, Henning

    2013-01-01

    One of the principal goals in the design of photonic crystals is the engineering of band gaps and defect states. Drawing on the concepts of band-structure topology, I here describe the formation of exponentially localized, topologically protected midgap states in photonic systems with spatially distributed gain and loss. When gain and loss are suitably arranged these states maintain their topological protection and then acquire a selectively tunable amplification rate. This finds applications in the beam dynamics along a photonic lattice and in the lasing of quasi-one-dimensional photonic crystals.

  3. Complexity and Chaos - State-of-the-Art; Formulations and Measures of Complexity

    Science.gov (United States)

    2007-09-01

    interpretation and description. That is the complexity of encoding the realisation into a descriptive code and decoding it back into a realisation of... GSM -05-20001 (http://www.dialog.com). Edmonds, Bruce, 1999. Syntactic Measures of Complexity. PhD Thesis. University of Manchester, number of pages

  4. Challenging the Research Base of the Common Core State Standards: A Historical Reanalysis of Text Complexity

    Science.gov (United States)

    Gamson, David A.; Lu, Xiaofei; Eckert, Sarah Anne

    2013-01-01

    The widely adopted Common Core State Standards (CCSS) call for raising the level of text complexity in textbooks and reading materials used by students across all grade levels in the United States; the authors of the English Language Arts component of the CCSS build their case for higher complexity in part upon a research base they say shows a…

  5. Mood states modulate complexity in heartbeat dynamics: A multiscale entropy analysis

    Science.gov (United States)

    Valenza, G.; Nardelli, M.; Bertschy, G.; Lanata, A.; Scilingo, E. P.

    2014-07-01

    This paper demonstrates that heartbeat complex dynamics is modulated by different pathological mental states. Multiscale entropy analysis was performed on R-R interval series gathered from the electrocardiogram of eight bipolar patients who exhibited mood states among depression, hypomania, and euthymia, i.e., good affective balance. Three different methodologies for the choice of the sample entropy radius value were also compared. We show that the complexity level can be used as a marker of mental states being able to discriminate among the three pathological mood states, suggesting to use heartbeat complexity as a more objective clinical biomarker for mental disorders.

  6. Complexity Leadership Theory: A United States Marine Corps Historical Overlay

    Science.gov (United States)

    2017-05-25

    service’s ability to innovate across the gap between organizational resources and an “uncertain” and “complex” future operating environment. As the...around the ability of each service to innovate across the gap between organizational resources and an “uncertain” and “complex” future operating...complexity. As a large organization attempts to achieve its purpose, it must identify, link, and execute the best emerging ideas and strategies from

  7. A State Recognition Approach for Complex Equipment Based on a Fuzzy Probabilistic Neural Network

    Directory of Open Access Journals (Sweden)

    Jing Xu

    2016-05-01

    Full Text Available Due to the traditional state recognition approaches for complex electromechanical equipment having had the disadvantages of excessive reliance on complete expert knowledge and insufficient training sets, real-time state identification system was always difficult to be established. The running efficiency cannot be guaranteed and the fault rate cannot be reduced fundamentally especially in some extreme working conditions. To solve these problems, an online state recognition method for complex equipment based on a fuzzy probabilistic neural network (FPNN was proposed in this paper. The fuzzy rule base for complex equipment was established and a multi-level state space model was constructed. Moreover, a probabilistic neural network (PNN was applied in state recognition, and the fuzzy functions and quantification matrix were presented. The flowchart of proposed approach was designed. Finally, a simulation example of shearer state recognition and the industrial application with an accuracy of 90.91% were provided and the proposed approach was feasible and efficient.

  8. The complex impact structure Serra da Cangalha, Tocantins State, Brazil

    Science.gov (United States)

    Kenkmann, Thomas; Vasconcelos, Marcos A. R.; Crósta, Alvaro P.; Reimold, Wolf U.

    2011-06-01

    Serra da Cangalha is a complex impact structure with a crater diameter of 13,700 m and a central uplift diameter of 5800 m. New findings of shatter cones, planar fractures, feather features, and possible planar deformation features are presented. Several ring-like features that are visible on remote sensing imagery are caused by selective erosion of tilted strata. The target at Serra da Cangalha is composed of Devonian to Permian sedimentary rocks, mainly sandstones that are interlayered with siltstone and claystones. NNE-SSW and WNW-ESE-striking joint sets were present prior to the impact and also overprinted the structure after its formation. As preferred zones of weakness, these joint sets partly controlled the shape of the outer perimeter of the structure and, in particular, affected the deformation within the central uplift. Joints in radial orientation to the impact center did not undergo a change in orientation during tilting of strata when the central uplift was formed. These planes were used as major displacement zones. The asymmetry of the central uplift, with preferred overturning of strata in the northern to western sector, may suggest a moderately oblique impact from a southerly direction. Buckle folding of tilted strata, as well as strata overturning, indicates that the central uplift became gravitationally unstable at the end of crater formation.

  9. Excited state decay of cyclometalated polypyridine ruthenium complexes: insight from theory and experiment.

    Science.gov (United States)

    Kreitner, Christoph; Heinze, Katja

    2016-09-21

    Deactivation pathways of the triplet metal-to-ligand charge transfer ((3)MLCT) excited state of cyclometalated polypyridine ruthenium complexes with [RuN5C](+) coordination are discussed on the basis of the available experimental data and a series of density functional theory calculations. Three different complex classes are considered, namely with [Ru(N^N)2(N^C)](+), [Ru(N^N^N)(N^C^N)](+) and [Ru(N^N^N)(N^N^C)](+) coordination modes. Excited state deactivation in these complex types proceeds via five distinct decay channels. Vibronic coupling of the (3)MLCT state to high-energy oscillators of the singlet ground state ((1)GS) allows tunneling to the ground state followed by vibrational relaxation (path A). A ligand field excited state ((3)MC) is thermally accessible via a (3)MLCT →(3)MC transition state with the (3)MC state being strongly coupled to the (1)GS surface via a low-energy minimum energy crossing point (path B). Furthermore, a (3)MLCT →(1)GS surface crossing point directly couples the triplet and singlet potential energy surfaces (path C). Charge transfer states either with higher singlet character or with different orbital parentage and intrinsic symmetry restrictions are thermally populated which promote non-radiative decay via tunneling to the (1)GS state (path D). Finally, the excited state can decay via phosphorescence (path E). The dominant deactivation pathways differ for the three individual complex classes. The implications of these findings for isoelectronic iridium(iii) or iron(ii) complexes are discussed. Ultimately, strategies for optimizing the emission efficiencies of cyclometalated polypyridine complexes of d(6)-metal ions, especially Ru(II), are suggested.

  10. Application of Bipartite Entangled States to Quantum Mechanical Version of Complex Wavelet Transforms

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    We introduce the bipartite entangled states to present a quantum mechanical version of complex wavelet transform. Using the technique of integral within an ordered product of operators we show that the complex wavelet transform can be studied in terms of various quantum state vectors in two-mode Fock space. In this way the creterion for mother wavelet can be examined quantum-mechanically and therefore more deeply.

  11. Quantum Query Complexity for Searching Multiple Marked States from an Unsorted Database

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    An important and usual sort of search problems is to find all marked states from an unsorted database with a large number of states. Grover's original quantum search algorithm is for finding single marked state with uncertainty, and it has been generalized to the case of multiple marked states, as well as been modified to find single marked state with certainty. However, the query complexity for finding all multiple marked states has not been addressed. We use a generalized Long's algorithm with high precision to solve such a problem. We calculate the approximate query complexity, which increases with the number of marked states and with the precision that we demand. In the end we introduce an algorithm for the problem on a "duality computer" and show its advantage over other algorithms.

  12. Methodological CASPT2 study of the valence excited states of an iron-porphyrin complex.

    Science.gov (United States)

    Ben Amor, Nadia; Soupart, Adrien; Heitz, Marie-Catherine

    2017-02-01

    The singlet valence excited states of an iron-porphyrin-pyrazine-carbonyl complex are investigated up to the Soret band (about 3 eV) using multi-state complete active space with perturbation at the second order (MS-CASPT2). This complex is a model for the active site of carboxy-hemoglobin/myoglobin. The spectrum of the excited states is rather dense, comprising states of different nature: d→π* transitions, d→d states, π→π* excitations of the porphyrin, and doubly excited states involving simultaneous intra-porphyrin π→π* and d→d transitions. Specific features of the MS-CASPT2 method are investigated. The effect of varying the number of roots in the state average calculation is quantified as well as the consequence of targeted modifications of the active space. The effect of inclusion of standard ionization potential-electron affinity (IPEA) shift in the perturbation treatment is also investigated.

  13. Solid-state NMR applied to photosynthetic light-harvesting complexes

    NARCIS (Netherlands)

    Pandit, A.; Groot, de H.J.M.

    2012-01-01

    This short review describes how solid-state NMR has provided a mechanistic and electronic picture of pigment–protein and pigment–pigment interactions in photosynthetic antenna complexes. NMR results on purple bacterial antenna complexes show how the packing of the protein and the pigments inside the

  14. Solid-state NMR applied to photosynthetic light-harvesting complexes

    NARCIS (Netherlands)

    Pandit, A.; Groot, de H.J.M.

    2012-01-01

    This short review describes how solid-state NMR has provided a mechanistic and electronic picture of pigment–protein and pigment–pigment interactions in photosynthetic antenna complexes. NMR results on purple bacterial antenna complexes show how the packing of the protein and the pigments inside the

  15. Modelling of Octahedral Manganese II Complexes with Inorganic Ligands: A Problem with Spin-States

    Directory of Open Access Journals (Sweden)

    Ludwik Adamowicz

    2003-08-01

    Full Text Available Abstract: Quantum mechanical ab initio UHF, MP2, MC-SCF and DFT calculations with moderate Gaussian basis sets were performed for MnX6, X = H2O, F-, CN-, manganese octahedral complexes. The correct spin-state of the complexes was obtained only when the counter ions neutralizing the entire complexes were used in the modelling at the B3LYP level of theory.

  16. Forbidden Electronic Transitions between the Singlet Ground State and the Triplet Excited State of Pt(II) Complexes.

    Science.gov (United States)

    Zheng, Greg Y.; Rillema, D. Paul; DePriest, Jeff; Woods, Clifton

    1998-07-13

    Direct access to the triplet emitting state from the ground state is observed for Pt(II) complexes containing heterocyclic (CwedgeC', CwedgeN, NwedgeN') and bis(diphenylphosphino)alkane (PwedgeP') ligands. Extinction coefficients for such transitions are in the range 4-25 M(-)(1) cm(-)(1). Emission quantum yields resulting from singlet-to-triplet excitation are as high as 61-77 times the emission quantum yields resulting from singlet-to-singlet excitation at 296 K. The intersystem crossing quantum yield from the singlet excited state to triplet emitting state is lower than 2% at 296 K but is greatly enhanced at 77 K. The forbidden electronic transition observed for Pt(II) complexes is attributed to result from spin-orbit coupling due to the presence of Pt(II) in the skeleton structure. The importance of excitation spectra on the computation of emission quantum yields is discussed.

  17. Intersections of potential energy surfaces of short-lived states: the complex analogue of conical intersections.

    Science.gov (United States)

    Feuerbacher, Sven; Sommerfeld, Thomas; Cederbaum, Lorenz S

    2004-02-15

    Whereas conical intersections between potential energy surfaces of bound states are well known, the interaction of short-lived states has been investigated only rarely. Here, we present several systematically constructed model Hamiltonians to study the topology of intersecting complex potential energy surfaces describing short-lived states: We find the general phenomenon of doubly intersecting complex energy surfaces, i.e., there are two points instead of one as in the case of bound states where the potential energy surfaces coalesce. In addition, seams of intersections of the respective real and imaginary parts of the potential energy surfaces emanate from these two points. Using the Sigma* and Pi* resonance states of the chloroethene anion as a practical example, we demonstrate that our complete linear model Hamiltonian is able to reproduce all phenomena found in explicitly calculated ab initio complex potential energy surfaces.

  18. Water and energy balance in the cultivated and bake soil in a montane area in Paraiba, Brazil; Balanco hidrico e de energia em solo cultivado e sem vegetacao, para as condicoes do brejo paraibano

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Jose Romualdo de Sousa

    2004-02-01

    In the areas of rain fed agriculture it is very important to quantify losses of water by evapotranspiration and soil evaporation. The methods used for measuring evapotranspiration and/or evaporation varies from direct measurements techniques, using lysimeters, to measurements of the water and energy balances. The precision lysimeters have high cost, being only used for research purposes. The water and energy balances methods have been very used due the simplicity, robustness and lower cost. Therefore, the objective of this study was to assess the water and energy balance components in the soil cultivated with cowpea (Vigna unguiculata (L) Walp) and without vegetation, besides comparing the methods used to determine the cowpea evapotranspiration. Two experiments (2002 and 2003) were performed in the 4 ha area of the Centro de Ciencias Agrarias, UFPB, municipality of Areia, Paraiba State (6 deg C 58 S, 5 deg C 41 W). To determine the energy balance, the area was instrumented with a rain gauge, a pyrano meter, a net radiometer, and sensors for measuring air temperature and humidity, and wind speed in two levels. Two locals, in the soil, were instrumented with two temperature sensors located at 2.0 cm and 8.0 cm below soil surface and one heat flux plate placed at 5.0 cm below soil surface. The measurements were recorded every 30 minutes on a data logger. To determine the water balance, three plots were installed, composed one-meter access tube for neutron probe measurements, and 8 tensiometers. The results show very good correlation between the aerodynamic method and the Bowen ration energy balance method, for all atmospherics and soil water conditions. For the two years, in average 72% of the net radiation was used by crop evapotranspiration. The energy and water balance can be used, the determine the crop evapotranspiration and soil evaporation, and regardless of the method used, the major water use by crop occurred in the reproductive stage. In the year of 2002

  19. Calculating the Lifetimes of Metastable States with Complex Density Functional Theory.

    Science.gov (United States)

    Zhou, Yongxi; Ernzerhof, Matthias

    2012-07-19

    Among other applications, complex absorbing potentials (CAPs) have proven to be useful tools in the theory of metastable states. They facilitate the conversion of unbound states of a finite lifetime into normalized bound states with a complex energy. Adding CAPs to a conventional Hamiltonian turns it into a non-Hermitian operator. Recently, we introduced a complex density functional theory (CODFT) that extends the Kohn-Sham method to the realm of non-Hermitian systems. Here, we combine CAPs with CODFT and present the first application of CODFT to metastable systems. In particular, we consider the negative ions of the beryllium atom and the nitrogen molecule. Using conventional exchange-correlation functionals as functionals of a complex density, the resonance positions and the resonance lifetimes are obtained, and they are in line with the findings of other studies.

  20. Crossover of high and low spin states in transition metal complexes

    CERN Document Server

    Raebiger, Hannes; Yasuhara, Hiroshi

    2012-01-01

    The stability of high vs. low spin states of transition metal complexes has been interpreted by ligand field theory, which is a perturbation theory of the electron-electron interaction. The present first principles calculation of a series of five cobalt complexes shows that the electron-electron interaction energy difference between the two states (i) exhibits the opposite trend to the total energy difference as the ligand nuclear charge varies, and (ii) is three or four orders of magnitude greater than the total energy difference. A new interpretation of the crossover of high and low spin states is given in terms of the chemical bonding.

  1. Intermolecular Vibrations of the Complex of NO in the nsσ Rydberg States and Ar

    OpenAIRE

    Tsuji, Kazuhide; Shibuya, Kazuhiko; Obi, Kinichi

    1995-01-01

    The resonance enhanced multiphoton ionization method has been applied to the study of NO-Ar van der Waals complex in the nsσ (n = 3,4) Rydberg states. We have assigned the intermolecular vibrations appearing in the ×X˜ excitation spectrum of the complex. The bending structure appeared only with the excitation of the stretching mode in the à state, which was interpreted by intermolecular forces. The E˜-à excitation spectra were independent of the initial intermolecular level in the à state an...

  2. Tracking excited-state charge and spin dynamics in iron coordination complexes

    DEFF Research Database (Denmark)

    Zhang, Wenkai; Alonso-Mori, Roberto; Bergmann, Uwe

    2014-01-01

    to spin state, can elucidate the spin crossover dynamics of [Fe(2,2'-bipyridine)(3)](2+) on photoinduced metal-to-ligand charge transfer excitation. We are able to track the charge and spin dynamics, and establish the critical role of intermediate spin states in the crossover mechanism. We anticipate......Crucial to many light-driven processes in transition metal complexes is the absorption and dissipation of energy by 3d electrons(1-4). But a detailed understanding of such non-equilibrium excited-state dynamics and their interplay with structural changes is challenging: a multitude of excited...... states and possible transitions result in phenomena too complex to unravel when faced with the indirect sensitivity of optical spectroscopy to spin dynamics(5) and the flux limitations of ultrafast X-ray sources(6,7). Such a situation exists for archetypal poly-pyridyl iron complexes, such as [Fe(2...

  3. Analysis of Pilot Feedback Regarding the Use of State Awareness Technologies During Complex Situations

    Science.gov (United States)

    Evans, Emory; Young, Steven D.; Daniels, Taumi; Santiago-Espada, Yamira; Etherington, Tim

    2016-01-01

    A flight simulation study was conducted at NASA Langley Research Center to evaluate flight deck systems that (1) predict aircraft energy state and/or autoflight configuration, (2) present the current state and expected future state of automated systems, and/or (3) show the state of flight-critical data systems in use by automated systems and primary flight instruments. Four new technology concepts were evaluated vis-à-vis current state-of-the-art flight deck systems and indicators. This human-in-the-loop study was conducted using commercial airline crews. Scenarios spanned a range of complex conditions and several emulated causal factors and complexity in recent accidents involving loss of state awareness by pilots (e.g. energy state, automation state, and/or system state). Data were collected via questionnaires administered after each flight, audio/video recordings, physiological data, head and eye tracking data, pilot control inputs, and researcher observations. This paper strictly focuses on findings derived from the questionnaire responses. It includes analysis of pilot subjective measures of complexity, decision making, workload, situation awareness, usability, and acceptability.

  4. Carving complex many-atom entangled states by single-photon detection

    CERN Document Server

    Chen, Wenlan; Duan, Yiheng; Braverman, Boris; Zhang, Hao; Vuletic, Vladan

    2015-01-01

    We propose a versatile and efficient method to generate a broad class of complex entangled states of many atoms via the detection of a single photon. For an atomic ensemble contained in a strongly coupled optical cavity illuminated by weak single- or multi-frequency light, the atom-light interaction entangles the frequency spectrum of a transmitted photon with the collective spin of the atomic ensemble. Simple time-resolved detection of the transmitted photon then projects the atomic ensemble into a desired pure entangled state. Complex entangled states such as multicomponent Schroedinger cat states can be generated with high fidelity. This probabilistic but fast heralded state-carving method can be made quasi-deterministic by repeated trial and feedback, yields high success probability per trial, and can be implemented with existing technology.

  5. Identifying the magnetoconductance responses by the induced charge transfer complex states in pentacene-based diodes

    Science.gov (United States)

    Huang, Wei-Shun; Lee, Tsung-Hsun; Guo, Tzung-Fang; Huang, J. C. A.; Wen, Ten-Chin

    2012-07-01

    We investigate the magnetoconductance (MC) responses in photocurrent, unipolar injection, and bipolar injection regimes in pentacene-based diodes. Both photocurrent and bipolar injection contributed MC responses show large difference in MC line shape, which are attributed to triplet-polaron interaction modulated by the magnetic field dependent singlet fission and the intersystem crossing of the polaron pair, respectively. By blending 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane into pentacene, all the MC responses are suppressed but the MC response at unipolar injection regime is enhanced, which is attributed to the induced charge transfer complex states (CT complex states). This work identify the MC responses between single carrier contributed MC and exciton related MC by the induced CT complex states.

  6. Realistic and verifiable coherent control of excitonic states in a light harvesting complex

    CERN Document Server

    Hoyer, Stephan; Montangero, Simone; Sarovar, Mohan; Calarco, Tommaso; Plenio, Martin B; Whaley, K Birgitta

    2013-01-01

    We explore the feasibility of coherent control of excitonic dynamics in light harvesting complexes despite the open nature of these quantum systems. We establish feasible targets for phase and phase/amplitude control of the electronically excited state populations in the Fenna-Mathews-Olson (FMO) complex and analyze the robustness of this control. We further present two possible routes to verification of the control target, with simulations for the FMO complex showing that steering of the excited state is experimentally verifiable either by extending excitonic coherence or by producing novel states in a pump-probe setup. Our results provide a first step toward coherent control of these systems in an ultrafast spectroscopy setup.

  7. Localized excitations in nonlinear complex systems current state of the art and future perspectives

    CERN Document Server

    Cuevas-Maraver, Jesús; Frantzeskakis, Dimitri; Karachalios, Nikos; Kevrekidis, Panayotis; Palmero-Acebedo, Faustino

    2014-01-01

    The study of nonlinear localized excitations is a long-standing challenge for research in basic and applied science, as well as engineering, due to their importance in understanding and predicting phenomena arising in nonlinear and complex systems, but also due to their potential for the development and design of novel applications. This volume is a compilation of chapters representing the current state-of-the-art on the field of localized excitations and their role in the dynamics of complex physical systems.

  8. Density of phonon states in the light-harvesting complex II of green plants

    CERN Document Server

    Pieper, J K; Irrgang, K D; Renger, G

    2002-01-01

    In photosynthetic antenna complexes, the coupling of electronic transitions to low-frequency vibrations of the protein matrix (phonons) plays an essential role in light absorption and ultra-fast excitation energy transfer (EET). The model calculations presented here indicate that inelastic neutron scattering experiments provide invaluable information on the phonon density of states for light-harvesting complex II, which may permit a consistent interpretation of contradictory results from high-resolution optical spectroscopy. (orig.)

  9. A universal indicator of critical state transitions in noisy complex networked systems

    OpenAIRE

    Junhao Liang; Yanqing Hu; Guanrong Chen; Tianshou Zhou

    2017-01-01

    Critical transition, a phenomenon that a system shifts suddenly from one state to another, occurs in many real-world complex networks. We propose an analytical framework for exactly predicting the critical transition in a complex networked system subjected to noise effects. Our prediction is based on the characteristic return time of a simple one-dimensional system derived from the original higher-dimensional system. This characteristic time, which can be easily calculated using network data,...

  10. Programming off and on states in chromatin: mechanisms of Polycomb and trithorax group complexes.

    Science.gov (United States)

    Simon, Jeffrey A; Tamkun, John W

    2002-04-01

    Polycomb and trithorax group proteins are evolutionarily conserved chromatin components that maintain stable states of gene expression. Recent studies have identified and characterized several multiprotein complexes containing these transcriptional regulators. Advances in understanding molecular activities of these complexes in vitro, and functional domains present in their subunits, suggest that they control transcription through multistep mechanisms that involve nucleosome modification, chromatin remodeling, and interaction with general transcription factors.

  11. (13)C and (15)N solid-state NMR studies on albendazole and cyclodextrin albendazole complexes.

    Science.gov (United States)

    Ferreira, M João G; García, A; Leonardi, D; Salomon, Claudio J; Lamas, M Celina; Nunes, Teresa G

    2015-06-05

    (13)C and (15)N solid-state nuclear magnetic resonance (NMR) spectra were recorded from albendazole (ABZ) and from ABZ:β-cyclodextrin, ABZ:methyl-β-cyclodextrin, ABZ:hydroxypropyl-β-cyclodextrin and ABZ:citrate-β-cyclodextrin, which were prepared by the spray-drying technique. ABZ signals were typical of a crystalline solid for the pure drug and of an amorphous compound obtained from ABZ:cyclodextrin samples. Relevant spectral differences were correlated with chemical interaction between ABZ and cyclodextrins. The number and type of complexes revealed a strong dependence on the cyclodextrin group substituent. Solid-state NMR data were consistent with the presence of stable inclusion complexes.

  12. Macroscopic description of complex adaptive networks co-evolving with dynamic node states

    CERN Document Server

    Wiedermann, Marc; Heitzig, Jobst; Lucht, Wolfgang; Kurths, Jürgen

    2015-01-01

    In many real-world complex systems, the time-evolution of the network's structure and the dynamic state of its nodes are closely entangled. Here, we study opinion formation and imitation on an adaptive complex network which is dependent on the individual dynamic state of each node and vice versa to model the co-evolution of renewable resources with the dynamics of harvesting agents on a social network. The adaptive voter model is coupled to a set of identical logistic growth models and we show that in such systems, the rate of interactions between nodes as well as the adaptive rewiring probability play a crucial role for the sustainability of the system's equilibrium state. We derive a macroscopic description of the system which provides a general framework to model and quantify the influence of single node dynamics on the macroscopic state of the network and is applicable to many fields of study, such as epidemic spreading or social modeling.

  13. Anonymous As a Cyber Tribe: A New Model for Complex, Non-State Cyber Actors

    Science.gov (United States)

    2015-05-01

    non- state cyber actors. The Air Force values a professional workplace that strictly prohibits racism , sexism, lewd material, and most forms of...AU/ACSC/LIDOWSKI, R/AY15 AIR COMMAND AND STAFF COLLEGE AIR UNIVERSITY ANONYMOUS AS A CYBER TRIBE: A NEW MODEL FOR COMPLEX, NON- STATE ...government or the Department of Defense. In accordance with Air Force Instruction 51-303, it is not copyrighted, but is the property of the United

  14. Parameter and State Estimation of Large-Scale Complex Systems Using Python Tools

    Directory of Open Access Journals (Sweden)

    M. Anushka S. Perera

    2015-07-01

    Full Text Available This paper discusses the topics related to automating parameter, disturbance and state estimation analysis of large-scale complex nonlinear dynamic systems using free programming tools. For large-scale complex systems, before implementing any state estimator, the system should be analyzed for structural observability and the structural observability analysis can be automated using Modelica and Python. As a result of structural observability analysis, the system may be decomposed into subsystems where some of them may be observable --- with respect to parameter, disturbances, and states --- while some may not. The state estimation process is carried out for those observable subsystems and the optimum number of additional measurements are prescribed for unobservable subsystems to make them observable. In this paper, an industrial case study is considered: the copper production process at Glencore Nikkelverk, Kristiansand, Norway. The copper production process is a large-scale complex system. It is shown how to implement various state estimators, in Python, to estimate parameters and disturbances, in addition to states, based on available measurements.

  15. Complex shifts between food web states in response to whole-ecosystem manipulations

    NARCIS (Netherlands)

    Schröder, A.; Persson, L.; de Roos, A.M.

    2012-01-01

    Food webs can respond in surprising and complex ways to temporary alterations in their species composition. When such a perturbation is reversed, food webs have been shown to either return to the pre-perturbation community state or remain in the food web configuration that established during the pert

  16. Universal data-based method for reconstructing complex networks with binary-state dynamics

    Science.gov (United States)

    Li, Jingwen; Shen, Zhesi; Wang, Wen-Xu; Grebogi, Celso; Lai, Ying-Cheng

    2017-03-01

    To understand, predict, and control complex networked systems, a prerequisite is to reconstruct the network structure from observable data. Despite recent progress in network reconstruction, binary-state dynamics that are ubiquitous in nature, technology, and society still present an outstanding challenge in this field. Here we offer a framework for reconstructing complex networks with binary-state dynamics by developing a universal data-based linearization approach that is applicable to systems with linear, nonlinear, discontinuous, or stochastic dynamics governed by monotonic functions. The linearization procedure enables us to convert the network reconstruction into a sparse signal reconstruction problem that can be resolved through convex optimization. We demonstrate generally high reconstruction accuracy for a number of complex networks associated with distinct binary-state dynamics from using binary data contaminated by noise and missing data. Our framework is completely data driven, efficient, and robust, and does not require any a priori knowledge about the detailed dynamical process on the network. The framework represents a general paradigm for reconstructing, understanding, and exploiting complex networked systems with binary-state dynamics.

  17. Stark spectroscopy of the light-harvesting complex II in different oligomerisation states

    NARCIS (Netherlands)

    Palacios, M.A.; Frese, R.N.; Gradinaru, C.C.; Stokkum, van I.H.M.; Premvardhan, L.L.; Horton, P.; Ruban, A.V.; Grondelle, van R.; Amerongen, van H.

    2003-01-01

    The electric field-induced absorption changes (Stark effect) of light-harvesting complex 11 (LHCII) in different oligomerisation states-monomeric, trimeric and aggregated-have been probed at 77 K. All the chlorophyll (Chl) a molecules exhibit electro-optic properties in the Q(y) absorption region ch

  18. Inversion formula and Parsval theorem for complex continuous wavelet transforms studied by entangled state representation

    CERN Document Server

    Hu, Li-yun

    2009-01-01

    In a preceding Letter (Opt. Lett. 32, 554 (2007)) we have proposed complex continuous wavelet transforms (CCWTs) and found Laguerre--Gaussian mother wavelets family. In this work we present the inversion formula and Parsval theorem for CCWT by virtue of the entangled state representation, which makes the CCWT theory complete. A new orthogonal property of mother wavelet in parameter space is revealed.

  19. Rotational State Microwave Mixing for Laser Cooling of Complex Diatomic Molecules

    Science.gov (United States)

    Yeo, Mark; Hummon, Matthew T.; Collopy, Alejandra L.; Yan, Bo; Hemmerling, Boerge; Chae, Eunmi; Doyle, John M.; Ye, Jun

    2015-06-01

    We demonstrate the mixing of rotational states in the ground electronic state using microwave radiation to enhance optical cycling in the molecule yttrium (II) monoxide (YO). This mixing technique is used in conjunction with a frequency modulated and chirped continuous wave laser to slow longitudinally a cryogenic buffer-gas beam of YO. We generate a flux of YO below 10 m /s , directly loadable into a three-dimensional magneto-optical trap. This technique opens the door for laser cooling of diatomic molecules with more complex loss channels due to intermediate states.

  20. Low-heating solid state synthetic reactions of cyclopeantadienyl organolanthanide complexes

    Institute of Scientific and Technical Information of China (English)

    ZHU Ming; LI Yanrong; LUO Jun; ZHOU Xigeng

    2003-01-01

    A novel and simple one-step, solid state reaction of multicomponent systems has been developed to synthesize cyclopentadienyl-containing organolanthanide complexes, in which the effects of the coordinated solvent molecules and the nature of the reactants were also studied. We also studied the solid state decomposition reaction of Cp2YbPz(HPz), and the formation of [CpYb(Pz)2]z may indicate that the constrained environment in solid state can lead to a novel chemical transformation, with product selectivity possibly different from that in the liquid phase.

  1. Occurrence and identification of the etiologic agents of plant diseases in cactus (Opuntia ficus-indica Mill. in the semi-arid region of Paraiba

    Directory of Open Access Journals (Sweden)

    Anne Evelyne Franco de Souza

    2010-01-01

    Full Text Available Cactus forage (Opuntia ficus-indica Mill., intensely cultivated in dry regions of northeast Brazil, although well adapted to the harsh semi-arid climate is affected by major problems such as pests and diseases, responsible for significant losses in production. This study aimed to investigate the occurrence and diversity of the etiologic agents of diseases of cactus cultivated in 38 municipalities in the semi-arid region of Paraiba. The analyses were conducted and processed at the Laboratory of Phytopathology of the Centro de Ciências Agrárias da Universidade Federal da Paraíba, in Areia - PB. Starting from sick cladodes isolations, multiplications and identifications of the found microorganisms were made. The identification of the microorganisms was achieved through observations of the macro and micromorphological characteristics of the cultures and tests of Gram and pathogenicity. Great incidence and diversity of microorganisms was verified in the cacti researched, but the highest occurrence was mainly that of fungus. The fungi of widest occurrence were: Scytallidium lignicola, Alternate tenuis, Macrophomina phaseolina, Cladosporium cladosporides, Lasiodiplodia theobromae, Fusarium oxysporum f. sp. opuntiarum, Curvularia lunata, Aspergillus niger, Nigrospora sphaerica, Colletotrichum gloeosporioides, Exserohilum turcicum, Pestalotia pitospora, Rhizopus stolonifer, Rhizoctonia solani and Sphaceloma protearum. A bacterium was also detected that was suspected to belong to the Erwinia sp. strain. Satisfaction of the Postulates of Koch proved the infectious nature of the detected microorganisms. High occurrence of the fungus S. lignicola, an agent of scale rot disease in 100% of the places researched, was observed. This fact is of great concern, since the progression of the disease can cause significant losses in production.

  2. Occurrence and identification of the etiologic agents of plant diseases in cactus (Opuntia ficus-indica Mill. in the semi-arid region of Paraiba

    Directory of Open Access Journals (Sweden)

    Anne Evelyne Franco de Souza

    2010-09-01

    Full Text Available Cactus forage (Opuntia ficus-indica Mill., intensely cultivated in dry regions of northeast Brazil, although well adapted to the harsh semi-arid climate is affected by major problems such as pests and diseases, responsible for significant losses in production. This study aimed to investigate the occurrence and diversity of the etiologic agents of diseases of cactus cultivated in 38 municipalities in the semi-arid region of Paraiba. The analyses were conducted and processed at the Laboratory of Phytopathology of the Centro de Ciências Agrárias da Universidade Federal da Paraíba, in Areia – PB. Starting from sick cladodes isolations, multiplications and identifications of the found microorganisms were made. The identification of the microorganisms was achieved through observations of the macro and micromorphological characteristics of the cultures and tests of Gram and pathogenicity. Great incidence and diversity of microorganisms was verified in the cacti researched, but the highest occurrence was mainly that of fungus. The fungi of widest occurrence were: Scytallidium lignicola, Alternate tenuis, Macrophomina phaseolina, Cladosporium cladosporides, Lasiodiplodia theobromae, Fusarium oxysporum f. sp. opuntiarum, Curvularia lunata, Aspergillus niger, Nigrospora sphaerica, Colletotrichum gloeosporioides, Exserohilum turcicum, Pestalotia pitospora, Rhizopus stolonifer, Rhizoctonia solani and Sphaceloma protearum. A bacterium was also detected that was suspected to belong to the Erwinia sp. strain. Satisfaction of the Postulates of Koch proved the infectious nature of the detected microorganisms. High occurrence of the fungus S. lignicola, an agent of scale rot disease in 100% of the places researched, was observed. This fact is of great concern, since the progression of the disease can cause significant losses in production.

  3. Quantum synchronization and quantum state sharing in an irregular complex network

    Science.gov (United States)

    Li, Wenlin; Li, Chong; Song, Heshan

    2017-02-01

    We investigate the quantum synchronization phenomenon of the complex network constituted by coupled optomechanical systems and prove that the unknown identical quantum states can be shared or distributed in the quantum network even though the topology is varying. Considering a channel constructed by quantum correlation, we show that quantum synchronization can sustain and maintain high levels in Markovian dissipation for a long time. We also analyze the state-sharing process between two typical complex networks, and the results predict that linked nodes can be directly synchronized, but the whole network will be synchronized only if some specific synchronization conditions are satisfied. Furthermore, we give the synchronization conditions analytically through analyzing network dynamics. This proposal paves the way for studying multi-interaction synchronization and achieving effective quantum information processing in a complex network.

  4. The Complexity of Quantum States and Transformations: From Quantum Money to Black Holes

    CERN Document Server

    Aaronson, Scott

    2016-01-01

    These are lecture notes from a weeklong course in quantum complexity theory taught at the Bellairs Research Institute in Barbados, February 21-25, 2016. The focus is quantum circuit complexity---i.e., the minimum number of gates needed to prepare a given quantum state or apply a given unitary transformation---as a unifying theme tying together several topics of recent interest in the field. Those topics include the power of quantum proofs and advice states; how to construct quantum money schemes secure against counterfeiting; and the role of complexity in the black-hole information paradox and the AdS/CFT correspondence (through connections made by Harlow-Hayden, Susskind, and others). The course was taught to a mixed audience of theoretical computer scientists and quantum gravity / string theorists, and starts out with a crash course on quantum information and computation in general.

  5. Quantum synchronization and quantum state sharing in an irregular complex network.

    Science.gov (United States)

    Li, Wenlin; Li, Chong; Song, Heshan

    2017-02-01

    We investigate the quantum synchronization phenomenon of the complex network constituted by coupled optomechanical systems and prove that the unknown identical quantum states can be shared or distributed in the quantum network even though the topology is varying. Considering a channel constructed by quantum correlation, we show that quantum synchronization can sustain and maintain high levels in Markovian dissipation for a long time. We also analyze the state-sharing process between two typical complex networks, and the results predict that linked nodes can be directly synchronized, but the whole network will be synchronized only if some specific synchronization conditions are satisfied. Furthermore, we give the synchronization conditions analytically through analyzing network dynamics. This proposal paves the way for studying multi-interaction synchronization and achieving effective quantum information processing in a complex network.

  6. Excited state potential energy surfaces of bistridentate RuII complexes - A TD-DFT study

    Science.gov (United States)

    Österman, Tomas; Persson, Petter

    2012-10-01

    Time-dependent density functional theory (TD-DFT) calculations have been used to investigate low-energy singlet and triplet excited state potential energy surfaces (PES) of two prototype RuII-bistridentate complexes: [RuII(tpy)2]2+ (tpy is 2,2':6',2''-terpyridine) and [RuII(dqp)2]2+ (dqp is 2,6-di(quinolin-8-yl)pyridine). Solvent effects were considered using a self-consistent reaction field scheme. The calculations provide information about the excited state manifold along pathways for activated decay of metal-to-ligand charge-transfer (MLCT) excited states via metal-centered (MC) states for the two complexes. Significant differences in the energy profiles of the investigated PESs are explained through characterization of the electronic properties of the involved states calculated by the TD-DFT calculations. Finally, implications of the computational results for the design of octahedral metal complexes utilizing ligand field splitting (LFS) strategies for efficient light-harvesting in photochemical applications such as artificial photosynthesis are discussed.

  7. Single-molecule spectroscopy reveals photosynthetic LH2 complexes switch between emissive states.

    Science.gov (United States)

    Schlau-Cohen, Gabriela S; Wang, Quan; Southall, June; Cogdell, Richard J; Moerner, W E

    2013-07-01

    Photosynthetic organisms flourish under low light intensities by converting photoenergy to chemical energy with near unity quantum efficiency and under high light intensities by safely dissipating excess photoenergy and deleterious photoproducts. The molecular mechanisms balancing these two functions remain incompletely described. One critical barrier to characterizing the mechanisms responsible for these processes is that they occur within proteins whose excited-state properties vary drastically among individual proteins and even within a single protein over time. In ensemble measurements, these excited-state properties appear only as the average value. To overcome this averaging, we investigate the purple bacterial antenna protein light harvesting complex 2 (LH2) from Rhodopseudomonas acidophila at the single-protein level. We use a room-temperature, single-molecule technique, the anti-Brownian electrokinetic trap, to study LH2 in a solution-phase (nonperturbative) environment. By performing simultaneous measurements of fluorescence intensity, lifetime, and spectra of single LH2 complexes, we identify three distinct states and observe transitions occurring among them on a timescale of seconds. Our results reveal that LH2 complexes undergo photoactivated switching to a quenched state, likely by a conformational change, and thermally revert to the ground state. This is a previously unobserved, reversible quenching pathway, and is one mechanism through which photosynthetic organisms can adapt to changes in light intensities.

  8. Structural oxidation state studies of the manganese cluster in the oxygen evolving complex of photosystem II

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Wenchuan [Univ. of California, Berkeley, CA (United States)

    1994-11-01

    X-ray absorption spectroscopy (XAS) was performed on Photosystem II (PSII)-enriched membranes prepared from spinach to explore: (1) the correlation between structure and magnetic spin state of the Mn cluster in the oxygen evolving complex (OEC) in the S2 state; and (2) the oxidation state changes of the Mn cluster in the flash-induced S-states. The structure of the Mn cluster in the S2 state with the g~4 electron paramagnetic resonance (EPR) signal (S2-g4 state) was compared with that in the S2 state with multiline signal (S2-MLS state) and the S1 state. The S2-g4 state has a higher XAS inflection point energy than that of the S1 state, indicating the oxidation of Mn in the advance from the S1 to the S2-g4 state. Differences in the edge shape and in the extended X-ray absorption fine structure (EXAFS) show that the structure of the Mn cluster in the S2-g4 state is different from that in the S2-MLS or the S1 state. In the S2-g4 state, the second shell of backscatterers from the Mn absorber contains two Mn-Mn distances of 2.73 Å and 2.85 Å. Very little distance disorder exists in the second shell of the S1 or S2-MLS states. The third shell of the S2-g4 state at about 3.3 Å also contains increased heterogeneity relative to that of the S2-MLS or the S1 state. Various S-states were prepared at room-temperature by saturating, single-turnover flashes. The flash-dependent oscillation in the amplitude of the MLS was used to characterize the S-state composition and to construct "pure" S-state Mn K-edge spectra. The edge position shifts to higher energy by 1.8 eV upon the S1 → S2 transition.

  9. Modelling excited states of weakly bound complexes with density functional theory.

    Science.gov (United States)

    Briggs, Edward A; Besley, Nicholas A

    2014-07-28

    The binding within the ethene-argon and formaldehyde-methane complexes in the ground and electronically excited states is studied with equation of motion coupled cluster theory (EOM-CCSD), second-order Møller-Plesset perturbation theory (MP2) and density functional theory with dispersion corrections (DFT-D). Electronically excited states are studied within MP2 and Kohn-Sham DFT formalisms by exploiting a procedure called the maximum overlap method that allows convergence of the relevant self-consistent field equations to higher energy (or excited state) solutions. Potential energy curves computed using MP2 are in good agreement with the EOM-CCSD calculations for both the valence and Rydberg excited states studied. For the DFT-D approach, B3LYP-D3/aug-cc-pVTZ calculations are found to be in agreement with EOM-CCSD for the ground and valence excited states. However, for the π3s Rydberg state of ethene-argon and the n3s Rydberg state of formaldehyde-methane significant deviation is observed, and this disagreement with EOM-CCSD is present for a variety of DFT-D based approaches. Variation of the parameters within the D2 dispersion correction results in closer agreement with EOM-CCSD for the Rydberg states but demonstrates that a different parameterisation from the ground state is required for these states. This indicates that time-dependent density functional theory calculations based upon a DFT-D reference may be satisfactory for excitations to valence states, but will potentially be inaccurate for excitations to Rydberg states, or more generally states where the nature of the electron density is significantly different from the ground state.

  10. Cation-mediated conversion of the state of charge in uranium arene inverted-sandwich complexes

    Energy Technology Data Exchange (ETDEWEB)

    Camp, Clement; Mougel, Victor; Pecaut, Jacques; Mazzanti, Marinella [Laboratoire de Reconnaissance Ionique et Chimie de Coordination, SCIB, UMR-E3 CEA-UJF, INAC, CEA-Grenoble (France); Maron, Laurent [LCPNO, CNRS and INSA, UPS, Universite de Toulouse (France)

    2013-12-16

    Two new arene inverted-sandwich complexes of uranium supported by siloxide ancillary ligands [K{U(OSi(OtBu)_3)_3}{sub 2}(μ-η{sup 6}:η{sup 6}-C{sub 7}H{sub 8})] (3) and [K{sub 2}{U(OSi(OtBu)_3)_3}{sub 2}(μ-η{sup 6}:η{sup 6}-C{sub 7}H{sub 8})] (4) were synthesized by the reduction of the parent arene-bridged complex [{U(OSi(OtBu)_3)_3}{sub 2}(μ-η{sup 6}:η{sup 6}-C{sub 7}H{sub 8})] (2) with stoichiometric amounts of KC{sub 8} yielding a rare family of inverted-sandwich complexes in three states of charge. The structural data and computational studies of the electronic structure are in agreement with the presence of high-valent uranium centers bridged by a reduced tetra-anionic toluene with the best formulation being U{sup V}-(arene{sup 4-})-U{sup V}, KU{sup IV}-(arene{sup 4-})-U{sup V}, and K{sub 2}U{sup IV}-(arene{sup 4-})-U{sup IV} for complexes 2, 3, and 4 respectively. The potassium cations in complexes 3 and 4 are coordinated to the siloxide ligands both in the solid state and in solution. The addition of KOTf (OTf=triflate) to the neutral compound 2 promotes its disproportionation to yield complexes 3 and 4 (depending on the stoichiometry) and the U{sup IV} mononuclear complex [U(OSi(OtBu){sub 3}){sub 3}(OTf)(thf){sub 2}] (5). This unprecedented reactivity demonstrates the key role of potassium for the stability of these complexes. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Biological correlates of complex posttraumatic stress disorder—state of research and future directions

    Directory of Open Access Journals (Sweden)

    Zoya Marinova

    2015-04-01

    Full Text Available Complex posttraumatic stress disorder (PTSD presents with clinical features of full or partial PTSD (re-experiencing a traumatic event, avoiding reminders of the event, and a state of hyperarousal together with symptoms from three additional clusters (problems in emotional regulation, negative self-concept, and problems in interpersonal relations. Complex PTSD is proposed as a new diagnostic entity in ICD-11 and typically occurs after prolonged and complex trauma. Here we shortly review current knowledge regarding the biological correlates of complex PTSD and compare it to the relevant findings in PTSD. Recent studies provide support to the validity of complex PTSD as a separate diagnostic entity; however, data regarding the biological basis of the disorder are still very limited at this time. Further studies focused on complex PTSD biological correlates and replication of the initial findings are needed, including neuroimaging, neurobiochemical, genetic, and epigenetic investigations. Identification of altered biological pathways in complex PTSD may be critical to further understand the pathophysiology and optimize treatment strategies.

  12. Tristable and multiple bistable activity in complex random binary networks of two-state units

    CERN Document Server

    Christ, Simon; Schimansky-Geier, Lutz

    2016-01-01

    We study complex networks of stochastic two-state units. Our aim is to model discrete stochastic excitable dynamics with a rest and an excited state. These two states are assumed to possess different waiting time distributions. The rest state is treated as an activation process with an exponentially distributed life time, whereas the latter in the excited state shall have a constant mean which may originate from any distribution. The activation rate of any single unit is determined by its neighbors according to a random complex network structure. In order to treat this problem in an analytical way, we use a heterogeneous mean-field approximation yielding a set of equations general valid for uncorrelated random networks. Based on this derivation we focus on random binary networks where the network is solely comprised of nodes with either of two degrees. The ratio between the two degrees is shown to be a crucial parameter. Dependent on the composition of the network the steady states show the usual transition f...

  13. Stereochemistry and solid-state circular dichroism spectroscopy of eight-coordinate chiral lanthanide complexes

    Institute of Scientific and Technical Information of China (English)

    ZHOU Nan; WAN ShiGang; ZHAO Jian; LIN YiJi; XUAN WeiMin; FANG XueMing; ZHANG Hui

    2009-01-01

    Eight-coordinate chiral lanthanide complexes[Eu(dbm)_3L~(RR)](1),[Eu(dbm)_3L~(SS)](2) and[Tb(dbm)_3L~(RR)](3)(L~(RR)/L~(SS)=(-)-1(+)-4,5-pineno-2,2'-bipyridine,Hdbm=dibenzoylmethane) were synthesized stereoselectively,which were characterized by UV-vis,CD spectra and X-ray single-crystal diffraction.The mirrorimage structure features of complexes 1 and 2 were obtained by combination of the solid-state CD spectra and the crystal structure analysis.After further comparison with the solid-state CD spectra of six-coordinate and seven-coordinate metal complexes containing β-diketone ligands,the CD spectraabsolute configuration correlation rule for the eight-coordinate β-diketonate lanthanide complexes was proposed through the exciton chirality method for the first time.The △ or Λ absolute configurations of complexes 1-3 with the distorted square antiprism geometry were confirmed by the X-ray single-crystal analysis.

  14. Stereochemistry and solid-state circular dichroism spectroscopy of eight-coordinate chiral lanthanide complexes

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Eight-coordinate chiral lanthanide complexes [Eu(dbm)3LRR](1),[Eu(dbm)3LSS](2) and [Tb(dbm)3LRR](3)(LRR/LSS =(-)-/(+)-4,5-pineno-2,2’-bipyridine,Hdbm = dibenzoylmethane) were synthesized stereoselectively,which were characterized by UV-vis,CD spectra and X-ray single-crystal diffraction.The mirrorimage structure features of complexes 1 and 2 were obtained by combination of the solid-state CD spectra and the crystal structure analysis.After further comparison with the solid-state CD spectra of six-coordinate and seven-coordinate metal complexes containing β-diketone ligands,the CD spectraabsolute configuration correlation rule for the eight-coordinate β-diketonate lanthanide complexes was proposed through the exciton chirality method for the first time.The △ or Λ absolute configurations of complexes 1―3 with the distorted square antiprism geometry were confirmed by the X-ray single-crystal analysis.

  15. Projected and Hidden Markov Models for calculating kinetics and metastable states of complex molecules

    CERN Document Server

    Noe, Frank; Prinz, Jan-Hendrik; Plattner, Nuria

    2013-01-01

    Markov state models (MSMs) have been successful in computing metastable states, slow relaxation timescales and associated structural changes, and stationary or kinetic experimental observables of complex molecules from large amounts of molecular dynamics simulation data. However, MSMs approximate the true dynamics by assuming a Markov chain on a clusters discretization of the state space. This approximation is difficult to make for high-dimensional biomolecular systems, and the quality and reproducibility of MSMs has therefore been limited. Here, we discard the assumption that dynamics are Markovian on the discrete clusters. Instead, we only assume that the full phase- space molecular dynamics is Markovian, and a projection of this full dynamics is observed on the discrete states, leading to the concept of Projected Markov Models (PMMs). Robust estimation methods for PMMs are not yet available, but we derive a practically feasible approximation via Hidden Markov Models (HMMs). It is shown how various molecula...

  16. Solvent dependence of the solid-state structures of salicylaldiminate magnesium amide complexes.

    Science.gov (United States)

    Rood, Jeffrey A; Landis, Ashley M; Forster, Daniel R; Goldkamp, Timothy; Oliver, Allen G

    2016-12-01

    There are challenges in using magnesium coordination complexes as reagents owing to their tendency to adopt varying aggregation states in solution and thus impacting the reactivity of the complexes. Many magnesium complexes are prone to ligand redistribution via Schlenk equilibrium due to the ionic character within the metal-ligand interactions. The role of the supporting ligand is often crucial for providing stability to the heteroleptic complex. Strategies to minimize ligand redistribution in alkaline earth metal complexes could include using a supporting ligand with tunable sterics and electronics to influence the degree of association to the metal atom. Magnesium bis(hexamethyldisilazide) was reacted with salicylaldimines [(1)L = N-(2,6-diisopropylphenyl)salicylaldimine and (2)L = 3,5-di-tert-butyl-N-(2,6-diisopropylphenyl)salicylaldimine] in either nondonor (toluene) or donor solvents [tetrahydrofuran (THF) or pyridine]. The structures of the magnesium complexes were studied in the solid state via X-ray diffraction. In the nondonor solvent, i.e. toluene, the heteroleptic complex bis{μ-2-[(2,6-diisopropylphenyl)iminomethyl]phenolato}-κ(3)N,O:O;κ(3)O:N,O-bis[(hexamethyldisilazido-κN)magnesium(II)], [Mg2(C19H22NO)2(C6H18NSi2)2] or [(1)LMgN(SiMe3)2]2, (1), was favored, while in the donor solvent, i.e. pyridine (pyr), the formation of the homoleptic complex {2,4-di-tert-butyl-6-[(2,6-diisopropylphenyl)iminomethyl]phenolato-κ(2)N,O}bis(pyridine-κN)magnesium(II) toluene monosolvate, [Mg(C27H38NO)2(C5H5N)2]·C5H5N or [{(2)L2Mg2(pyr)2}·pyr], (2), predominated. Heteroleptic complex (1) was crystallized from toluene, while homoleptic complexes (2) and the previously reported [(1)L2Mg·THF] [Quinque et al. (2011). Eur. J. Inorg. Chem. pp. 3321-3326] were crystallized from pyridine and THF, respectively. These studies support solvent-dependent ligand redistribution in solution. In-situ (1)H NMR experiments were carried out to further probe the solution behavior of

  17. Rotational state microwave mixing for laser cooling of complex diatomic molecules

    CERN Document Server

    Yeo, Mark; Collopy, Alejandra L; Yan, Bo; Hemmerling, Boerge; Chae, Eunmi; Doyle, John M; Ye, Jun

    2015-01-01

    We demonstrate the mixing of rotational states in the ground electronic state using microwave radiation to enhance optical cycling in the molecule yttrium (II) monoxide (YO). This mixing technique is used in conjunction with a frequency modulated and chirped continuous wave laser to slow longitudinally a cryogenic buffer gas beam of YO. We generate a measurable flux of YO below 10~m/s, directly loadable into a three-dimensional magneto-optical trap. This technique opens the door for laser cooling of molecules with more complex structure.

  18. Quantum transport in networks and photosynthetic complexes at the steady state.

    Directory of Open Access Journals (Sweden)

    Daniel Manzano

    Full Text Available Recently, several works have analysed the efficiency of photosynthetic complexes in a transient scenario and how that efficiency is affected by environmental noise. Here, following a quantum master equation approach, we study the energy and excitation transport in fully connected networks both in general and in the particular case of the Fenna-Matthew-Olson complex. The analysis is carried out for the steady state of the system where the excitation energy is constantly "flowing" through the system. Steady state transport scenarios are particularly relevant if the evolution of the quantum system is not conditioned on the arrival of individual excitations. By adding dephasing to the system, we analyse the possibility of noise-enhancement of the quantum transport.

  19. Quantum transport in networks and photosynthetic complexes at the steady state.

    Science.gov (United States)

    Manzano, Daniel

    2013-01-01

    Recently, several works have analysed the efficiency of photosynthetic complexes in a transient scenario and how that efficiency is affected by environmental noise. Here, following a quantum master equation approach, we study the energy and excitation transport in fully connected networks both in general and in the particular case of the Fenna-Matthew-Olson complex. The analysis is carried out for the steady state of the system where the excitation energy is constantly "flowing" through the system. Steady state transport scenarios are particularly relevant if the evolution of the quantum system is not conditioned on the arrival of individual excitations. By adding dephasing to the system, we analyse the possibility of noise-enhancement of the quantum transport.

  20. Nudged-elastic band method with two climbing images: finding transition states in complex energy landscapes

    CERN Document Server

    Zarkevich, Nikolai A

    2014-01-01

    The nudged-elastic band (NEB) method is modified with concomitant two climbing images (C2-NEB) to find a transition state (TS) in complex energy landscapes, such as those with serpentine minimal energy path (MEP). If a single climbing image (C1-NEB) successfully finds the TS, C2-NEB finds it with higher stability and accuracy. However, C2-NEB is suitable for more complex cases, where C1-NEB misses the TS because the MEP and NEB directions near the saddle point are different. Generally, C2-NEB not only finds the TS but guarantees that the climbing images approach it from the opposite sides along the MEP, and it estimates accuracy from the three images: the highest-energy one and its climbing neighbors. C2-NEB is suitable for fixed-cell NEB and the generalized solid-state NEB (SS-NEB).

  1. Steady-state and transient heat transfer through fins of complex geometry

    Directory of Open Access Journals (Sweden)

    Taler Dawid

    2014-06-01

    Full Text Available Various methods for steady-state and transient analysis of temperature distribution and efficiency of continuous-plate fins are presented. For a constant heat transfer coefficient over the fin surface, the plate fin can be divided into imaginary rectangular or hexangular fins. At first approximate methods for determining the steady-state fin efficiency like the method of equivalent circular fin and the sector method are discussed. When the fin geometry is complex, thus transient temperature distribution and fin efficiency can be determined using numerical methods. A numerical method for transient analysis of fins with complex geometry is developed. Transient temperature distributions in continuous fins attached to oval tubes is computed using the finite volume - finite element methods. The developed method can be used in the transient analysis of compact heat exchangers to calculate correctly the heat flow rate transferred from the finned tubes to the fluid.

  2. Crystal Structures of EF-G-Ribosome Complexes Trapped in Intermediate States of Translocation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jie; Lancaster, Laura; Donohue, John Paul; Noller, Harry F. [UCSC

    2013-11-12

    Translocation of messenger and transfer RNA (mRNA and tRNA) through the ribosome is a crucial step in protein synthesis, whose mechanism is not yet understood. The crystal structures of three Thermus ribosome-tRNA-mRNA–EF-G complexes trapped with β,γ-imidoguanosine 5'-triphosphate (GDPNP) or fusidic acid reveal conformational changes occurring during intermediate states of translocation, including large-scale rotation of the 30S subunit head and body. In all complexes, the tRNA acceptor ends occupy the 50S subunit E site, while their anticodon stem loops move with the head of the 30S subunit to positions between the P and E sites, forming chimeric intermediate states. Two universally conserved bases of 16S ribosomal RNA that intercalate between bases of the mRNA may act as “pawls” of a translocational ratchet. These findings provide new insights into the molecular mechanism of ribosomal translocation.

  3. Information processing reveals how microscopic components affect the macroscopic system-state in complex networks

    CERN Document Server

    Quax, Rick; Sloot, Peter M A

    2013-01-01

    Nature processes information. We observe this from physical systems, which register information in the system state, transfer information through interactions, and lose information due to thermal noise. Being able to quantify this information processing could lead to a unifying framework for a better understanding of complex systems. In this letter we present a formalism to describe to what extent a macroscopic system is affected by the microstates of its constituents. We study this numerically for a scale-free network of Ising-spins, a prototypical complex system, and present an answer to the unexplained phenomenon that real systems with a heterogeneous topology are mainly controlled by nodes with fewer connections. Counter to intuition we find that due to selective information dissipation, not the hubs but rather the intermediately connected nodes are remembered best by the system. Our study reveals that the framework of information processing improves our understanding of complex systems at large.

  4. Complex state variable- and disturbance observer-based current controllers for AC drives

    DEFF Research Database (Denmark)

    Dal, Mehmet; Teodorescu, Remus; Blaabjerg, Frede

    2013-01-01

    , extracted by a disturbance observer and then injected into the current controller. In this study, a revised version of a disturbance observer-based controller and a well known complex variable model-based design with a single set of complex pole are compared in terms of design aspects and performance...... of the parameter and the cross-coupling effect. Moreover, it provides a better performance, smooth and low noisy operation with respect to the complex variable controller....... of the stator current. In order to improve the current control performance an alternative current control strategy was proposed previously aiming to avoid the undesired cross-coupling and non-linearities between the state variables. These effects are assumed as disturbances arisen in the closed-loop path...

  5. A universal indicator of critical state transitions in noisy complex networked systems.

    Science.gov (United States)

    Liang, Junhao; Hu, Yanqing; Chen, Guanrong; Zhou, Tianshou

    2017-02-23

    Critical transition, a phenomenon that a system shifts suddenly from one state to another, occurs in many real-world complex networks. We propose an analytical framework for exactly predicting the critical transition in a complex networked system subjected to noise effects. Our prediction is based on the characteristic return time of a simple one-dimensional system derived from the original higher-dimensional system. This characteristic time, which can be easily calculated using network data, allows us to systematically separate the respective roles of dynamics, noise and topology of the underlying networked system. We find that the noise can either prevent or enhance critical transitions, playing a key role in compensating the network structural defect which suffers from either internal failures or environmental changes, or both. Our analysis of realistic or artificial examples reveals that the characteristic return time is an effective indicator for forecasting the sudden deterioration of complex networks.

  6. The T-shaped KrI2(ion-pair states) van der Waals complexes

    Science.gov (United States)

    Baturo, V. V.; Kevorkyants, R.; Lukashov, S. S.; Poretsky, S. A.; Pravilov, A. M.; Zhironkin, A. I.

    2017-09-01

    The T-shaped KrI2(E0g+) van der Waals complexes have been observed and studied for the first time. Analysis of the luminescence excitation spectra as well as luminescence spectra themselves in the spectral ranges, where the I2(E0g+ → B0u+, D0u+ → X0g+, β1g → A1u and D‧2g → A‧2u) transitions can occur, has been carried out. Branching ratios of the iodine molecule state formation and vibronic level population, as well as the potential parameters of the KrI2(E,vE = 0-8, nE) complexes have been determined. Binding energies of the KrI2(X0g+,vX = 0, nX = 0 and B0u+, vB = 19, nB = 0) complexes have been also estimated.

  7. A Hidden State in Light-Harvesting Complex II Revealed By Multipulse Spectroscopy.

    Science.gov (United States)

    van Oort, Bart; van Grondelle, Rienk; van Stokkum, Ivo H M

    2015-04-23

    Light-harvesting complex II (LHCII) is pivotal both for collecting solar radiation for photosynthesis, and for protection against photodamage under high light intensities (via a process called nonphotochemical quenching, NPQ). Aggregation of LHCII is associated with fluorescence quenching, and is used as an in vitro model system of NPQ. However, there is no agreement on the nature of the quencher and on the validity of aggregation as a model system. Here, we use ultrafast multipulse spectroscopy to populate a quenched state in unquenched (unaggregated) LHCII. The state shows characteristic features of lutein and chlorophyll, suggesting that it is an excitonically coupled state between these two compounds. This state decays in approximately 10 ps, making it a strong competitor for photodamage and photochemical quenching. It is observed in trimeric and monomeric LHCII, upon re-excitation with pulses of different wavelengths and duration. We propose that this state is always present, but is scarcely populated under low light intensities. Under high light intensities it may become more accessible, e.g. by conformational changes, and then form a quenching channel. The same state may be the cause of fluorescence blinking observed in single-molecule spectroscopy of LHCII trimers, where a small subpopulation is in an energetically higher state where the pathway to the quencher opens up.

  8. Solid-state characterization of sertraline base-β-cyclodextrin inclusion complex.

    Science.gov (United States)

    Ogawa, Noriko; Hashimoto, Takuro; Furuishi, Takayuki; Nagase, Hiromasa; Endo, Tomohiro; Yamamoto, Hiromitsu; Kawashima, Yoshiaki; Ueda, Haruhisa

    2015-03-25

    Sertraline is one of the serotonin-specific reuptake inhibitors that is effective in treating several disorders such as major depression, obsessive-compulsive disorder, panic disorder, and social phobia. It is marketed in the form of its hydrochloride salt, which exhibits better solubility in water than its free base form. However, the absorption of sertraline through biological membranes could be improved by enhancing the solubility of its base because it is more hydrophobic than sertraline hydrochloride. To clarify the mechanism for the interaction of sertraline base with β-CD, it is important to study the basic interaction between the β-CD ring and sertraline base. Therefore, in this study, the currently used hydrochloride salt form was converted into the free base and β-CD was used as a model for β-CD derivatives to evaluate the interaction between β-CD and the sertraline base. The solid-state physicochemical characteristics of the sertraline-β-CD complex were investigated by the phase solubility method, differential scanning calorimetry, Fourier transform IR spectroscopy, FT-Raman spectroscopy, powder X-ray diffraction, and (13)C cross-polarization magic-angle spinning NMR measurements. The results showed that sertraline base and β-CD form an inclusion complex, and the stoichiometric ratio of the solid-state sertraline base-β-CD complex is 1:1, which was estimated by the (1)H NMR measurements of the complex dissolved in DMSO-d6.

  9. Proton coupled electron transfer from the excited state of a ruthenium(II) pyridylimidazole complex.

    Science.gov (United States)

    Pannwitz, Andrea; Wenger, Oliver S

    2016-04-28

    Proton coupled electron transfer (PCET) from the excited state of [Ru(bpy)2pyimH](2+) (bpy = 2,2'-bipyridine; pyimH = 2-(2'-pyridyl)imidazole) to N-methyl-4,4'-bipyridinium (monoquat, MQ(+)) was studied. While this complex has been investigated previously, our study is the first to show that the formal bond dissociation free energy (BDFE) of the imidazole-N-H bond decreases from (91 ± 1) kcal mol(-1) in the electronic ground state to (43 ± 5) kcal mol(-1) in the lowest-energetic (3)MLCT excited state. This makes the [Ru(bpy)2pyimH](2+) complex a very strong (formal) hydrogen atom donor even when compared to metal hydride complexes, and this is interesting for light-driven (formal) hydrogen atom transfer (HAT) reactions with a variety of different substrates. Mechanistically, formal HAT between (3)MLCT excited [Ru(bpy)2pyimH](2+) and monoquat in buffered 1 : 1 (v : v) CH3CN/H2O was found to occur via a sequence of reaction steps involving electron transfer from Ru(ii) to MQ(+) coupled to release of the N-H proton to buffer base, followed by protonation of reduced MQ(+) by buffer acid. Our study is relevant in the larger contexts of photoredox catalysis and light-to-chemical energy conversion.

  10. Efeitos ambientais e genéticos sobre o ganho em peso diário de bovinos Nelore no Estado da Paraíba Genetic and environmental effects on Nellore cattle growth in Paraiba

    Directory of Open Access Journals (Sweden)

    José Lindenberg Rocha Sarmento

    2003-04-01

    Full Text Available Registros de 6.674 pesos de bovinos da raça Nelore nascidos entre 1975 e 1990 em duas fazendas no Estado da Paraíba foram utilizados para estudar efeitos ambientais e estimar parâmetros genéticos das características ganhos em peso diário do nascimento aos 205, dos 205 aos 365 e dos 365 aos 550 dias de idade. Os efeitos ambientais foram estudados usando-se o programa SAS®. O modelo incluiu o efeito aleatório de touro e os efeitos fixos de ano-mês-sexo, fazenda e idade da vaca como covariável linear e quadrática. Os componentes de (covariância usados para estimar os coeficientes de herdabilidade direta e materna foram obtidos pelo Método da Máxima Verossimilhança Restrita, usando o programa MTDFREML sob modelo animal. Todos os efeitos incluídos no modelo foram significativos, exceto o efeito de fazenda para o ganho diário do nascimento à desmama. As médias estimadas foram de 0,575 ± 0,089, 0,231 ± 0,114 e 0,283 ± 0,110 kg para ganhos em peso diário do nascimento aos 205, dos 205 aos 365 e dos 365 aos 550 dias de idade, respectivamente. As herdabilidades estimadas para efeito direto foram de 0,12, 042 e 0,21 e, para efeito materno, de 0,29, 0,00 e 0,00, na mesma ordem. Os coeficientes de herdabilidade indicam que a seleção baseada no ganho em peso pós-desmama até um ano de idade pode proporcionar considerável ganho genético.Records on 6,674 Nellore cattle weight, born from 1975 to 1990 in two farms located in Paraiba State were used to study environmental effects and to estimate genetic parameters for average daily gains from birth to 205 days, from 205 to 365 days and from 365 to 550 days. The SAS® program was used to study the environmental effects. The model included the random effect of sire and the fixed effects of year-month-sex, farm and age of the cow at calving as linear and quadratic covariate. The (covariance components used to estimate direct and maternal heritabilities were obtained by Derivative Free

  11. Avaliação de linhagens e cultivares de feijão-vagem de crescimento indeterminado, no município de Areia-PB Evaluation of breeding lines and cultivars of climbing snap beans in Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    Ademar P. Oliveira

    2001-07-01

    Full Text Available Avaliaram-se quinze linhagens (Hav 13, Hav 14, Hav 21, Hav 22, Hav 25, Hav 38, Hav 40, Hav 41, Hav 49, Hav 53, Hav 56, Hav 60, Hav 65, Hav 67 e Hav 68 e oito cultivares comerciais (Macarrão Favorito Ag 480, Macarrão Preferido Ag 482, Manteiga Maravilha Ag 481, Teresópolis Ag 484, Macarrão Bragança, Macarrão Trepador Topseed, Macarrão Trepador Hortivale e Macarrão Trepador Isla de feijão-vagem de crescimento indeterminado. O ensaio foi conduzido na Universidade Federal da Paraíba, em Areia, no período de março a agosto de 1999 em Latossolo Vermelho-Amarelo. As linhagens Hav 22 (31,6 t/ha, Hav 38 (35,00t/ha, Hav 41 (31,5 t/ha, Hav 68 (30,5 t/ha, e as cultivares Macarrão Favorito Ag 480 (30,3 t/ha, Macarrão Preferido Ag 482 (39,1 t/ha e Manteiga Maravilha Ag 481 (36,2 t/ha destacaram-se por apresentarem alta produtividade, peso médio de vagens de acordo com a preferência do mercado local, e teor de fibra dentro dos padrões comerciais. A cultivar Teresópolis Ag 484 (58,5 t/ha, embora tenha apresentado alta produtividade, necessita de estudos de mercado, para que possa ser indicada para os produtores, uma vez que apresenta vagens grandes e achatadas.Fifteen breeding lines (Hav 13; Hav 14; Hav 21; Hav 22; Hav 25; Hav 38; Hav 40; Hav 41; Hav 49; Hav 53; Hav 56; Hav 60; Hav 65; Hav 67 and Hav 68 and eight cultivars (Macarrão Favorito Ag 480; Macarrão Preferido Ag 482; Manteiga Maravilha Ag 481; Teresópolis Ag 484; Macarrão Bragança; Macarrão Trepador Topseed; Macarrão Trepador Hortivale and Macarrão Trepador ISLA of climbing snap beans were evaluated under field conditions in Areia, State of Paraiba, Brazil. The trial was carried out from March to August, 1999. The best results (high yield, good average weight and low fiber content of pods were obtained with the breeding lines Hav 22 (31.6 t/ha; Hav 38 (35.0 t/ha; Hav 41 (31.5 t/ha and Hav 68 (30.5 t/ha, and with the cultivars Macarrão Favorito Ag 480 (30.3 t/ha; Macarr

  12. Reconstructing Equation of State for Dark Energy in Double Complex Symmetric Gravitational Theory

    Institute of Scientific and Technical Information of China (English)

    SHAO Ying; GUI Yuan-Xing; WANG Wei

    2007-01-01

    We propose to study the accelerating expansion of the universe in the double complex symmetric gravitational theory (DCSGT). The universe we live in is taken as the real part of the whole spacetime M4C(J), which is double complex. By introducing the spatially flat FRW metric, not only the double Friedmann equations but also the two constraint conditions pJ = 0 and J2 = 1 are obtained. Furthermore, using parametric DL(z) ansatz, we reconstruct the ω′(z) and V(φ) for dark energy from real observational data. We find that in the two cases of J = i, pJ = 0, and J = ε, pJ ≠ 0, the corresponding equations of state ω′(z) remain close to -1 at present (z = 0) and change from below -1 to above -1. The results illustrate that the whole spacetime, i.e. the double complex spacetime M4C(J), may be either ordinary complex (J = i, pJ = 0) or hyperbolic complex (J = ε, pJ ≠ 0). And the fate of the universe would be Big Rip in the future.

  13. Paisaje, esclavitud y medio ambiente en la economía cafetalera brasileña: Vale do Paraiba, Siglo XIX

    Directory of Open Access Journals (Sweden)

    Marquese, Rafael

    2015-06-01

    Full Text Available The article analyses the landscape and labor management devices adopted in the nineteenth-century Paraiba Valley slave coffee plantations. It argues that the presence of an enormous mass of enslaved Africans in a turbulent local and global conjuncture framed by world competition between different coffee producers and increasing slave resistance led planters to adopt measures of landscape management that closely restricted slave autonomy in the labor process as they tried to extract the maxim amount of labor from the slaves. The outcome of these forms of landscape and labor management was a process of unprecedented environmental devastation. At the time of slavery crisis in the 1880s, these historical patterns turned against slaveholders, who however managed to maintain dominion over the land by means of a specific reconfiguration of the forms of agronomic exploitation.El artículo analiza las estrategias de administración del paisaje y del trabajo adoptadas en las plantaciones esclavistas del Valle de Paraíba a lo largo del siglo XIX. Sostiene que la presencia masiva de la población africana esclavizada, en un contexto local y global muy turbulento, marcado por la competencia entre los diferentes productores mundiales para el control de este artículo y por la intensificación de la resistencia esclava, condujo a la adopción, por los propietarios esclavistas, de las formas de administración del paisaje en sus haciendas que buscaron restringir la autonomía de los esclavos en el proceso de trabajo y, al mismo tiempo, explotar al máximo su capacidad de trabajo. El resultado de estas formas de administración del paisaje y del trabajo fue un proceso de devastación ambiental sin precedentes. En el momento de la crisis de la esclavitud en la década de 1880, estos patrones históricos se volvieron contra los propios esclavistas, que sin embargo lograron mantener el dominio sobre la tierra por medio de una reconfiguración específica de las

  14. Dark States in the Light-Harvesting complex 2 Revealed by Two-dimensional Electronic Spectroscopy

    Science.gov (United States)

    Ferretti, Marco; Hendrikx, Ruud; Romero, Elisabet; Southall, June; Cogdell, Richard J.; Novoderezhkin, Vladimir I.; Scholes, Gregory D.; van Grondelle, Rienk

    2016-02-01

    Energy transfer and trapping in the light harvesting antennae of purple photosynthetic bacteria is an ultrafast process, which occurs with a quantum efficiency close to unity. However the mechanisms behind this process have not yet been fully understood. Recently it was proposed that low-lying energy dark states, such as charge transfer states and polaron pairs, play an important role in the dynamics and directionality of energy transfer. However, it is difficult to directly detect those states because of their small transition dipole moment and overlap with the B850/B870 exciton bands. Here we present a new experimental approach, which combines the selectivity of two-dimensional electronic spectroscopy with the availability of genetically modified light harvesting complexes, to reveal the presence of those dark states in both the genetically modified and the wild-type light harvesting 2 complexes of Rhodopseudomonas palustris. We suggest that Nature has used the unavoidable charge transfer processes that occur when LH pigments are concentrated to enhance and direct the flow of energy.

  15. Spin state relaxation of iron complexes: The case for OPBE and S12g

    Directory of Open Access Journals (Sweden)

    Gruden Maja

    2015-01-01

    Full Text Available The structures of nine iron complexes that show a diversity of experimentally observed spin ground states are optimized and analyzed with Density Functional Theory (DFT. An extensive validation study of the new S12g functional is performed, with the discussion concerning the influence of the environment, geometry and its overall performance based on the comparison with the well proven OPBE functional. The OPBE and S12g functionals give the correct spin ground state for all investigated iron complexes. Since S12g performs remarkably well it can be considered a reliable tool for studying spin state energetics in complicated transition metal systems. [Ministerio de Ciencia e Innovación (MICINN, project CTQ2011-25086/BQU, the Ministerio de Economia y Competitividad (MINECO, project CTQ2014-59212/BQU and the DIUE of the Generalitat de Catalunya (project 2014SGR1202, and Xarxa de Referència en Química Teòrica i Computacional; MICINN and the FEDER fund (European Fund for Regional Development under grant UNGI10-4E-801, and the Serbian Ministry of Education and Science (Grant No. 172035. This work was performed in the framework of the COST action CM1305 "Explicit Control Over Spin-states in Technology and Biochemistry (ECOSTBio" (STSM reference: ECOST-STSM-CM1305-27360.

  16. Macroscopic description of complex adaptive networks coevolving with dynamic node states

    Science.gov (United States)

    Wiedermann, Marc; Donges, Jonathan F.; Heitzig, Jobst; Lucht, Wolfgang; Kurths, Jürgen

    2015-05-01

    In many real-world complex systems, the time evolution of the network's structure and the dynamic state of its nodes are closely entangled. Here we study opinion formation and imitation on an adaptive complex network which is dependent on the individual dynamic state of each node and vice versa to model the coevolution of renewable resources with the dynamics of harvesting agents on a social network. The adaptive voter model is coupled to a set of identical logistic growth models and we mainly find that, in such systems, the rate of interactions between nodes as well as the adaptive rewiring probability are crucial parameters for controlling the sustainability of the system's equilibrium state. We derive a macroscopic description of the system in terms of ordinary differential equations which provides a general framework to model and quantify the influence of single node dynamics on the macroscopic state of the network. The thus obtained framework is applicable to many fields of study, such as epidemic spreading, opinion formation, or socioecological modeling.

  17. Dark States in the Light-Harvesting complex 2 Revealed by Two-dimensional Electronic Spectroscopy.

    Science.gov (United States)

    Ferretti, Marco; Hendrikx, Ruud; Romero, Elisabet; Southall, June; Cogdell, Richard J; Novoderezhkin, Vladimir I; Scholes, Gregory D; van Grondelle, Rienk

    2016-02-09

    Energy transfer and trapping in the light harvesting antennae of purple photosynthetic bacteria is an ultrafast process, which occurs with a quantum efficiency close to unity. However the mechanisms behind this process have not yet been fully understood. Recently it was proposed that low-lying energy dark states, such as charge transfer states and polaron pairs, play an important role in the dynamics and directionality of energy transfer. However, it is difficult to directly detect those states because of their small transition dipole moment and overlap with the B850/B870 exciton bands. Here we present a new experimental approach, which combines the selectivity of two-dimensional electronic spectroscopy with the availability of genetically modified light harvesting complexes, to reveal the presence of those dark states in both the genetically modified and the wild-type light harvesting 2 complexes of Rhodopseudomonas palustris. We suggest that Nature has used the unavoidable charge transfer processes that occur when LH pigments are concentrated to enhance and direct the flow of energy.

  18. Complexity

    CERN Document Server

    Gershenson, Carlos

    2011-01-01

    The term complexity derives etymologically from the Latin plexus, which means interwoven. Intuitively, this implies that something complex is composed by elements that are difficult to separate. This difficulty arises from the relevant interactions that take place between components. This lack of separability is at odds with the classical scientific method - which has been used since the times of Galileo, Newton, Descartes, and Laplace - and has also influenced philosophy and engineering. In recent decades, the scientific study of complexity and complex systems has proposed a paradigm shift in science and philosophy, proposing novel methods that take into account relevant interactions.

  19. The B850/B875 Photosynthetic Complex Ground and Excited State are Both Coherent

    CERN Document Server

    Squire, R H; Rubio, A; Ingles, J R; Cunningham, W A

    2016-01-01

    A bacterial photosynthetic light harvesting complex PLHC absorbs a photon and transfers this energy almost perfectly at room temperature RT to a Reaction Center RC, where charge separation occurs. While there are a number of possible light absorbers involved in this process, our focus is the B850 and B875 complexes. We propose that the dominant feature of the ground states in the B850 ring and the B875 open chain are pseudo one dimensional metals due to each bacteriochlorophyll a BChl containing a coordinated magnesium ion Mg2+. The Mg ion structure undergoes a static Peierls distortion that results in symmetry breaking that changes the even spacing of the Mg/BChl molecules comprising the chains to the experimentally observed Mg/BChl dimers. The results are charge density waves CDW, one for each type of the two complexes that result in an energy gap in the single particle electronic spectrum and coherent phonon s spanning the entire rings. The ground state CDWs seem to have two functions the first is to form ...

  20. Engineering Complex Embedded Systems with State Analysis and the Mission Data System

    Science.gov (United States)

    Ingham, Michel D.; Rasmussen, Robert D.; Bennett, Matthew B.; Moncada, Alex C.

    2004-01-01

    It has become clear that spacecraft system complexity is reaching a threshold where customary methods of control are no longer affordable or sufficiently reliable. At the heart of this problem are the conventional approaches to systems and software engineering based on subsystem-level functional decomposition, which fail to scale in the tangled web of interactions typically encountered in complex spacecraft designs. Furthermore, there is a fundamental gap between the requirements on software specified by systems engineers and the implementation of these requirements by software engineers. Software engineers must perform the translation of requirements into software code, hoping to accurately capture the systems engineer's understanding of the system behavior, which is not always explicitly specified. This gap opens up the possibility for misinterpretation of the systems engineer s intent, potentially leading to software errors. This problem is addressed by a systems engineering methodology called State Analysis, which provides a process for capturing system and software requirements in the form of explicit models. This paper describes how requirements for complex aerospace systems can be developed using State Analysis and how these requirements inform the design of the system software, using representative spacecraft examples.

  1. Bending crystals. Solid state photomechanical properties of transition metal complexes containing semiquinonate ligands

    Indian Academy of Sciences (India)

    Cortlandt G Pierpont

    2002-08-01

    The properties of transition metal complexes containing catecholate and radical semiquinonate ligands have often been found to be unusual and unexpected. Crystals of Rh(CO)2(3,6-DBSQ), containing the 3,6-di-tert-butyl-1,2-semiquinonate ligand, form as long thin needles that are observed to bend reversibly upon irradiation with NIR light. Crystallographic characterization reveals a stacked solid state lattice with planar molecules aligned with metal atoms atop one another. Electronic spectra recorded in the solid state and in solution show an intense band at 1600 nm that maps the energy dependence of crystal bend angle. The transition is a property of the stacked assembly, rather than of an individual complex molecule, and appears associated with an MLCT process that transfers charge from an antibonding band formed by interacting Rh $d_{z}^{2}$ orbitals to the vacant quinone * orbital. Related observations have been made on the [Co(-pyz)(3,6-DBSQ)(3,6-DBCat)] polymer. Photomechanical properties appear associated with electronic transitions that lead to a physical change in axial length of a linear polymer, coupled with a soft solid state lattice that permits axial contraction/expansion without crystal fracture.

  2. A simple state-contingent pricing rule for complex intertemporal externalities

    Energy Technology Data Exchange (ETDEWEB)

    McKitrick, Ross [Guelph Univ., ON (Canada). Dept. of Economics

    2011-01-15

    Some externalities, such as global warming, involve complex relationships between emissions and an environmental state variable, with effects over lags of uncertain length. Coming up with theoretically-motivated and practical policy options in such cases has proven difficult. Deterministic intertemporal general equilibrium models yield what appear to be feasible optimal price paths, but only by assuming away many key uncertainties, nor do they specify how the possibility of new information should affect the policy path. Bayesian models allow limited uncertainty and optimal learning based on observed effects of policy changes, but suggest a discouraging delay before optimal policy can be identified. A full insurance model suggests that risk aversion and 'fat-tailed' probabilities of catastrophe imply an implausibly (or at least impractically) large risk premium, implying that practical policy decisions depend so critically on uncertain parameters as to be unavoidably arbitrary. This paper proposes an entirely new approach based on the observation that the situation giving rise to a complex intertemporal externality also yields an observable state variable that contains information relevant to the identification of the optimal policy path. I derive a simple transformation by which the state variable can yield a good approximation to the optimal externality price. I outline assumptions sufficient to yield the transformation, and present numerical examples that illustrate its ability to follow linear and nonlinear first-best price paths. A specific application to greenhouse gases is proposed. (author)

  3. Excited state dynamics in photosynthetic reaction center and light harvesting complex 1

    Science.gov (United States)

    Strümpfer, Johan; Schulten, Klaus

    2012-08-01

    Key to efficient harvesting of sunlight in photosynthesis is the first energy conversion process in which electronic excitation establishes a trans-membrane charge gradient. This conversion is accomplished by the photosynthetic reaction center (RC) that is, in case of the purple photosynthetic bacterium Rhodobacter sphaeroides studied here, surrounded by light harvesting complex 1 (LH1). The RC employs six pigment molecules to initiate the conversion: four bacteriochlorophylls and two bacteriopheophytins. The excited states of these pigments interact very strongly and are simultaneously influenced by the surrounding thermal protein environment. Likewise, LH1 employs 32 bacteriochlorophylls influenced in their excited state dynamics by strong interaction between the pigments and by interaction with the protein environment. Modeling the excited state dynamics in the RC as well as in LH1 requires theoretical methods, which account for both pigment-pigment interaction and pigment-environment interaction. In the present study we describe the excitation dynamics within a RC and excitation transfer between light harvesting complex 1 (LH1) and RC, employing the hierarchical equation of motion method. For this purpose a set of model parameters that reproduce RC as well as LH1 spectra and observed oscillatory excitation dynamics in the RC is suggested. We find that the environment has a significant effect on LH1-RC excitation transfer and that excitation transfers incoherently between LH1 and RC.

  4. Bounded-Error Quantum State Identification and Exponential Separations in Communication Complexity

    CERN Document Server

    Gavinsky, D; Kempe, J; Regev, O; Gavinsky, Dmitry; Kempe, Julia; Regev, Oded; Wolf, Ronald de

    2005-01-01

    We consider the problem of bounded-error quantum state identification: given either state \\alpha_0 or state \\alpha_1, we are required to output `0', `1' or `?' ("don't know"), such that conditioned on outputting `0' or `1', our guess is correct with high probability. The goal is to maximize the probability of not outputting `?'. We prove a direct product theorem: if we're given two such problems, with optimal probabilities a and b, respectively, and the states in the first problem are pure, then the optimal probability for the joint bounded-error state identification problem is O(ab). Our proof is based on semidefinite programming duality and may be of wider interest. Using this result, we present two exponential separations in the simultaneous message passing model of communication complexity. Both are shown in the strongest possible sense. First, we describe a relation that can be computed with O(log n) classical bits of communication in the presence of shared randomness, but needs Omega(n^{1/3}) communicat...

  5. Solid-state nanopore detection of protein complexes: applications in healthcare and protein kinetics.

    Science.gov (United States)

    Freedman, Kevin J; Bastian, Arangassery R; Chaiken, Irwin; Kim, Min Jun

    2013-03-11

    Protein conjugation provides a unique look into many biological phenomena and has been used for decades for molecular recognition purposes. In this study, the use of solid-state nanopores for the detection of gp120-associated complexes are investigated. They exhibit monovalent and multivalent binding to anti-gp120 antibody monomer and dimers. In order to investigate the feasibility of many practical applications related to nanopores, detection of specific protein complexes is attempted within a heterogeneous protein sample, and the role of voltage on complexed proteins is researched. It is found that the electric field within the pore can result in unbinding of a freely translocating protein complex within the transient event durations measured experimentally. The strong dependence of the unbinding time with voltage can be used to improve the detection capability of the nanopore system by adding an additional level of specificity that can be probed. These data provide a strong framework for future protein-specific detection schemes, which are shown to be feasible in the realm of a 'real-world' sample and an automated multidimensional method of detecting events.

  6. Statistical correlation of fractional oscillator response by complex spectral moments and state variable expansion

    Science.gov (United States)

    Pinnola, Francesco Paolo

    2016-10-01

    The statistical characterization of the oscillator response with non-integer order damping under Gaussian noise represents an important challenge in the modern stochastic mechanics. In fact, this kind of problem appears in several issues of different type (wave propagation in viscoelastic media, Brownian motion, fluid dynamics, RLC circuit, etc.). The aim of this paper is to provide a stochastic characterization of the stationary response of linear fractional oscillator forced by normal white noise. In particular, this paper shows a new method to obtain the correlation function by exact complex spectral moments. These complex quantities contain all the information to describe the random processes but in the considered case their analytical evaluation needs some mathematical manipulations. For this reason such complex spectral moment characterization is used in conjunction with a fractional-order state variable analysis. This kind of analysis permits to find the exact expression of complex spectral moments, and the correlation function by using the Mellin transform. Moreover, the proposed approach provides an analytical expression of the response variance of the fractional oscillator. Capability and efficiency of the present method are shown in the numerical examples in which correlation and variance of fractional oscillator response are found and compared with those obtained by Monte Carlo simulations.

  7. Steady-state and time-resolved fluorometry of fluorescent pollutants and heavy metal complexes

    Science.gov (United States)

    Resch, Ute; Rurack, Knut

    1997-05-01

    Time-resolved laser-induced fluorescence spectroscopy is one of the most sensitive optical methods which is well suited for on-line in situ analysis. Here, three examples for the steady- state and time-resolved fluorescence analysis of environmentally important analytes, the fluorescent monoaromatic hydrocarbons benzene, toluene, and xylene as well as non fluorescent heavy metal ions forming a fluorescent complex with a cation coordinating fluorescence probe, are presented and the potential of both methods is discussed. For BTX, various mixtures of the spectrally similar compounds B, T, and X showing different fluorescence lifetimes were studied with both methods. As an example for fluorometric metal ion analysis, the fluorescence probe BP(OH)2 (2,2'-bipyridyl- 3,3'-diol) was employed for the determination of d10 metal ions in water and the newly developed fluorescence probe APTA for the detection of Cu(II). Cation complexation of BP(OH2 yields spectrally very similar complexes which differ in their fluorescence lifetimes. Complexation of APTA to Cu(II) leads to small spectral changes and a strong increase in fluorescence quantum yield and lifetime. For the analytes studied, a comparison of the detection limits, standard deviations, and linear dynamic range of both methods clearly demonstrates the analytical potential of time-resolved fluorometry.

  8. Cutaneous leishmaniasis caused by members of Leishmania braziliensis complex in Nayarit, State of Mexico

    Directory of Open Access Journals (Sweden)

    Gustavo Sanchez-Tejeda

    2001-01-01

    Full Text Available An epidemiological study was carried out in the northern Mexican state, Nayarit. Fourteen patients with possible cutaneous leishmaniasis skin lesions gave positive Montenegro skin tests. Biopsies were taken from the skin ulcer and analyzed by polymerase chain reaction (PCR with specific primers for the Leishmania mexicana complex; however all biopsies were not amplified. PCR carried out with specific primers for the L. braziliensis complex resulted in the amplification of all patient DNA. DNA from 12 out of 14 biopsies gave positive amplification with primers species specific for L. (Viannia braziliensis and hybridized with a species specific L. (V. braziliensis probe. These results demonstrate the presence in Nayarit of at least two members of the L. braziliensis complex. Most of the cutaneous lesions were caused by L. (V. braziliensis and two by another species belonging to the L. braziliensis complex. As far as we are aware, this is the first report of L. (V. braziliensis in Nayarit. The main risk factor associated with the contraction of this disease in Nayarit is attributed to working on coffee plantations.

  9. Cutaneous leishmaniasis caused by members of Leishmania braziliensis complex in Nayarit, State of Mexico.

    Science.gov (United States)

    Sanchez-Tejeda, G; Rodríguez, N; Parra, C I; Hernandez-Montes, O; Barker, D C; Monroy-Ostria, A

    2001-01-01

    An epidemiological study was carried out in the northern Mexican state, Nayarit. Fourteen patients with possible cutaneous leishmaniasis skin lesions gave positive Montenegro skin tests. Biopsies were taken from the skin ulcer and analyzed by polymerase chain reaction (PCR) with specific primers for the Leishmania mexicana complex; however all biopsies were not amplified. PCR carried out with specific primers for the L. braziliensis complex resulted in the amplification of all patient DNA. DNA from 12 out of 14 biopsies gave positive amplification with primers species specific for L. (Viannia) braziliensis and hybridized with a species specific L. (V.) braziliensis probe. These results demonstrate the presence in Nayarit of at least two members of the L. braziliensis complex. Most of the cutaneous lesions were caused by L. (V.) braziliensis and two by another species belonging to the L. braziliensis complex. As far as we are aware, this is the first report of L. (V.) braziliensis in Nayarit. The main risk factor associated with the contraction of this disease in Nayarit is attributed to working on coffee plantations.

  10. Complex for monitoring visual acuity and its application for evaluation of human psycho-physiological state

    Science.gov (United States)

    Sorokoumov, P. S.; Khabibullin, T. R.; Tolstaya, A. M.

    2017-01-01

    The existing psychological theories associate the movement of a human eye with its reactions to external change: what we see, hear and feel. By analyzing the glance, we can compare the external human response (which shows the behavior of a person), and the natural reaction (that they actually feels). This article describes the complex for detection of visual activity and its application for evaluation of the psycho-physiological state of a person. The glasses with a camera capture all the movements of the human eye in real time. The data recorded by the camera are transmitted to the computer for processing implemented with the help of the software developed by the authors. The result is given in an informative and an understandable report, which can be used for further analysis. The complex shows a high efficiency and stable operation and can be used both, for the pedagogic personnel recruitment and for testing students during the educational process.

  11. Spin States of Iron(III) in Highly Saddled Dodecaphenylporphyrin Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Ohya, T., E-mail: ohyat@pharm.teikyo-u.ac.jp; Takeda, J.; Sato, M. [Teikyo University, Laboratory of Biophysics, Faculty of Pharmaceutical Sciences (Japan)

    2004-12-15

    Iron(III) complexes of highly saddled dodecaphenylporphyrin, Fe(DPP)X (X=Cl, Br or I) have been prepared and characterized by Moessbauer, UV-Vis and magnetic measurements. The Moessbauer spectra, recorded at temperatures from 5 to 300 K, contain two components A and B. Component A is attributed to iron(III) in a spin-admixed (S=3/2, 5/2) state. The UV-Vis spectra of solution samples of these complexes exhibit broad and red-shifted absorption bands. The effective magnetic moments derived from the molar magnetic susceptibilities measured by modified Gouy method at 298 K for X=Cl, Br and I are 5.52, 5.10 and 4.28 {mu}{sub B}, respectively.

  12. Semilocal and Hybrid Density Embedding Calculations of Ground-State Charge-Transfer Complexes

    CERN Document Server

    Laricchia, S; Della Sala, F; 10.1063/1.4795825

    2013-01-01

    We apply the frozen density embedding method, using a full relaxation of embedded densities through a freeze-and-thaw procedure, to study the electronic structure of several benchmark ground-state charge-transfer complexes, in order to assess the merits and limitations of the approach for this class of systems. The calculations are performed using both semilocal and hybrid exchange-correlation (XC) functionals. The results show that embedding calculations using semilocal XC functionals yield rather large deviations with respect to the corresponding supermolecular calculations. Due to a large error cancellation effect, however, they can often provide a relatively good description of the electronic structure of charge-transfer complexes, in contrast to supermolecular calculations performed at the same level of theory. On the contrary, when hybrid XC functionals are employed, both embedding and supermolecular calculations agree very well with each other and with the reference benchmark results. In conclusion, fo...

  13. Complex

    African Journals Online (AJOL)

    CLEMENT O BEWAJI

    Schiff bases and their complex compounds have been studied for their .... establishing coordination of the N–(2 – hydroxybenzyl) - L - α - valine Schiff base ..... (1967); “Spectrophotometric Identification of Organic Compounds”, Willey, New.

  14. Solid-state electrochemiluminescence of a novel iridium(Ⅲ) complex

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The sofid-state ECL behavior of a water-insoluble bis-cyclometalated (pq)2Ir(N-phMA) complex is presented, in which pq is a 2-phenylquinoline anion and N-phMA is N-phenyl methacrylamide, a monoanionic bidentate ligand. The MWNTs/(pq)2Ir(N-phMA) film, MWNTs/Ru(bpy)32+ film and (pq)2Ir(N-phMA) directly modified glassy carbon electrode were fabricated; only the MWNTs/(pq)2Ir(N-phMA) film can produce steady ECL in the presence of tri-n-propylamine as a coreactant.

  15. Combined Parameter and State Estimation Problem in a Complex Domain: RF Hyperthermia Treatment Using Nanoparticles

    Science.gov (United States)

    Bermeo Varon, L. A.; Orlande, H. R. B.; Eliçabe, G. E.

    2016-09-01

    The particle filter methods have been widely used to solve inverse problems with sequential Bayesian inference in dynamic models, simultaneously estimating sequential state variables and fixed model parameters. This methods are an approximation of sequences of probability distributions of interest, that using a large set of random samples, with presence uncertainties in the model, measurements and parameters. In this paper the main focus is the solution combined parameters and state estimation in the radiofrequency hyperthermia with nanoparticles in a complex domain. This domain contains different tissues like muscle, pancreas, lungs, small intestine and a tumor which is loaded iron oxide nanoparticles. The results indicated that excellent agreements between estimated and exact value are obtained.

  16. Evolution of the Hox gene complex from an evolutionary ground state.

    Science.gov (United States)

    Gehring, Walter J; Kloter, Urs; Suga, Hiroshi

    2009-01-01

    In this chapter, we consider the question of how the ordered clusters of Hox genes arose during evolution. Since ordered Hox clusters are found in all major superphyla, we have to assume that the Hox clusters arose before the Cambrian "explosion" giving rise to all of these taxa. Based on his studies of the bithorax complex (BX-C) in Drosophila Lewis considered the ground state to be the mesothoracic segment (T2) since the deletion of all of the genes of the BX-C leads to a transformation of all segments from T3 to A8/9 (the last abdominal segment) into T2 segments. We define the developmental ground state genetically, by assuming that loss-of-function mutants lead to transformations toward the ground state, whereas gain-of-function mutants lead to homeotic transformations away from the ground state. By this definition, T2 also represents the developmental ground state, if one includes the anterior genes, that is, those of the Antennapedia complex. We have reconstructed the evolution of the Hox cluster on the basis of known genetic mechanisms which involve unequal crossover and lead from an urhox gene, first to an anterior and a posterior gene and subsequently to intermediate genes which are progressively inserted, between the anterior and posterior genes. These intermediate genes are recombinant due to unequal crossover, whereas the anterior and posterior genes are not affected and therefore had the longest time to diverge from the urhox gene. The molecular phylogenetic analysis strongly supports this model. We consider the ground state to be both developmental and evolutionary and to represent the prototypic body segment. It corresponds to T2 and is specified by Antennapedia or Hox6, respectively. Experiments in the mouse also suggest that the ground state is a thoracic segment. Evolution leads from the prototypic segment to segmental divergence in both the anterior and posterior direction. The most anterior head and tail segments are specified by homeobox genes

  17. Protein dynamics tunes excited state positions in light-harvesting complex II.

    Science.gov (United States)

    Vrandecic, Kamarniso; Rätsep, Margus; Wilk, Laura; Rusevich, Leonid; Golub, Maksym; Reppert, Mike; Irrgang, Klaus-Dieter; Kühlbrandt, Werner; Pieper, Jörg

    2015-03-12

    Light harvesting and excitation energy transfer in photosynthesis are relatively well understood at cryogenic temperatures up to ∼100 K, where crystal structures of several photosynthetic complexes including the major antenna complex of green plants (LHC II) are available at nearly atomic resolution. The situation is much more complex at higher or even physiological temperatures, because the spectroscopic properties of antenna complexes typically undergo drastic changes above ∼100 K. We have addressed this problem using a combination of quasielastic neutron scattering (QENS) and optical spectroscopy on native LHC II and mutant samples lacking the Chl 2/Chl a 612 pigment molecule. Absorption difference spectra of the Chl 2/Chl a 612 mutant of LHC II reveal pronounced changes of spectral position and their widths above temperatures as low as ∼80 K. The complementary QENS data indicate an onset of conformational protein motions at about the same temperature. This finding suggests that excited state positions in LHC II are affected by protein dynamics on the picosecond time scale. In more detail, this means that at cryogenic temperatures the antenna complex is trapped in certain protein conformations. At higher temperature, however, a variety of conformational substates with different spectral position may be thermally accessible. At the same time, an analysis of the widths of the absorption difference spectra of Chl 2/Chl a 612 reveals three different reorganization energies or Huang-Rhys factors in different temperature ranges, respectively. These findings imply that (dynamic) pigment-protein interactions fine-tune electronic energy levels and electron-phonon coupling of LHC II for efficient excitation energy transfer at physiological temperatures.

  18. Towards Hybrid Online On-Demand Querying of Realtime Data with Stateful Complex Event Processing

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Qunzhi; Simmhan, Yogesh; Prasanna, Viktor K.

    2013-10-09

    Emerging Big Data applications in areas like e-commerce and energy industry require both online and on-demand queries to be performed over vast and fast data arriving as streams. These present novel challenges to Big Data management systems. Complex Event Processing (CEP) is recognized as a high performance online query scheme which in particular deals with the velocity aspect of the 3-V’s of Big Data. However, traditional CEP systems do not consider data variety and lack the capability to embed ad hoc queries over the volume of data streams. In this paper, we propose H2O, a stateful complex event processing framework, to support hybrid online and on-demand queries over realtime data. We propose a semantically enriched event and query model to address data variety. A formal query algebra is developed to precisely capture the stateful and containment semantics of online and on-demand queries. We describe techniques to achieve the interactive query processing over realtime data featured by efficient online querying, dynamic stream data persistence and on-demand access. The system architecture is presented and the current implementation status reported.

  19. Solid-state NMR applied to photosynthetic light-harvesting complexes.

    Science.gov (United States)

    Pandit, Anjali; de Groot, Huub J M

    2012-03-01

    This short review describes how solid-state NMR has provided a mechanistic and electronic picture of pigment-protein and pigment-pigment interactions in photosynthetic antenna complexes. NMR results on purple bacterial antenna complexes show how the packing of the protein and the pigments inside the light-harvesting oligomers induces mutual conformational stress. The protein scaffold produces deformation and electrostatic polarization of the BChl macrocycles and leads to a partial electronic charge transfer between the BChls and their coordinating histidines, which can tune the light-harvesting function. In chlorosome antennae assemblies, the NMR template structure reveals how the chromophores can direct their self-assembly into higher macrostructures which, in turn, tune the light-harvesting properties of the individual molecules by controlling their disorder, structural deformation, and electronic polarization without the need for a protein scaffold. These results pave the way for addressing the next challenge, which is to resolve the functional conformational dynamics of the lhc antennae of oxygenic species that allows them to switch between light-emitting and light-energy dissipating states.

  20. Assessing the costs of water and electrical energy for banana irrigated by sprinkler in State of Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    José Dantas Neto

    2008-12-01

    Full Text Available The main goal of this research was carried out an evaluation on costs of water and electricity for fruit irrigated by sprinkler irrigation in agricultural planning. Originally was obtained the demands of gross water and electricity for the cultivation of bananas for 15 municipalities spread over the Paraiba River, in the state of Paraiba, which was used sprinkler irrigation system. The city of João Pessoa, located in the lower Rio Paraiba, is the site of lowest consumption of water, requiring 37.71% of the amount required at county of Desterro for papaya. Desterro, is located in the sub-basin of the Taperoá, had the highest annual and daily evapotranspiration, combined with the lowest annual rainfall likely at a 75% probability of occurring. The cities were chosen because they had a greater variance in terms of climate, in order to examine various demands for irrigation. The rate of energy for Campina Grande has CELB as concessionaire of energy, and for other localities, SAELPA. The results showed that municipalities belonging to the sub-basin of the Taperoá require a higher water demand due to a higher evapotranspiration, and a low rainfall and hence a greater impact on costs.

  1. Oriented bilayers of a proteolipid complex, Annexin V phospholipids, for solid state NMR analyses

    Science.gov (United States)

    Saurel, O.; Demange, P.; Milon, A.

    1998-02-01

    We were able to obtain oriented bilayers in the presence of annexin V (35 kDa) and to measure structural and dynamic parameters. NMR results obtained so far show that annexin does not affect the structure of the membrane but modifies the dynamics of the phospholipids (T2e decrease). Our new method to prepare oriented biological samples, based on the preparation of small unilamellar proteolipid vesicles in biological buffers, should be suitable for any membrane protein phospholipid complex and for solid state NMR or neutron diffraction experiments. La préparation de petites vésicules protéo-lipidiques dans un tampon physiologique, nous a permis d'obtenir des bicouches orientées en présence d'annexine V (35 kDa) et de mesurer les paramètres structuraux et dynamiques de ce complexe protéolipidique. Les résultats obtenus par RMN du solide montrent que l'annexine n'affecte pas la structure en bicouche de la membrane mais modifie la dynamique des phospholipides (diminution du temps de relaxation T2e). Cette nouvelle méthode de préparation d'échantillons orientés peut être applicable à tout complexe protéine-phospholipides pour des études par RMN à l'état solide ou par diffraction des neutrons.

  2. Determination of electronic ground state properties of a dinuclear iron(II) spin crossover complex

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, T. O., E-mail: thbauer@rhrk.uni-kl.de [University of Kaiserslautern, Department of Physics (Germany); Schmitz, M.; Graf, M.; Kelm, H.; Krüger, H.-J. [University of Kaiserslautern, Department of Chemistry (Germany); Schünemann, V. [University of Kaiserslautern, Department of Physics (Germany)

    2016-12-15

    The dinuclear complex [(Fe(L-N{sub 4}Me{sub 2})){sub 2}(BiBzIm)](ClO{sub 4}){sub 2}⋅2EtCN (1) has been investigated by Mössbauer spectroscopy carried out in the temperature range from 5 to 150 K with externally applied magnetic fields of up to B = 5 T. By means of a consistent simulation of all experimental data sets within the Spin Hamiltonian formalism, the zero-field splitting D and the rhombicity parameter E/D of the ferrous high-spin (HS) site in this complex was determined to be D = −15.0 ± 1.0 cm{sup −1} and E/D = 0.33 respectively. The sign of the quadrupole splitting of the HS site is positive which indicates that this iron site of the dinuclear complex 1 has an electronic ground state with the d{sub xy} orbital being twofold occupied.

  3. Variance-Constrained State Estimation for Complex Networks With Randomly Varying Topologies.

    Science.gov (United States)

    Dong, Hongli; Hou, Nan; Wang, Zidong; Ren, Weijian

    2017-05-23

    This paper investigates the variance-constrained H∞ state estimation problem for a class of nonlinear time-varying complex networks with randomly varying topologies, stochastic inner coupling, and measurement quantization. A Kronecker delta function and Markovian jumping parameters are utilized to describe the random changes of network topologies. A Gaussian random variable is introduced to model the stochastic disturbances in the inner coupling of complex networks. As a kind of incomplete measurements, measurement quantization is taken into consideration so as to account for the signal distortion phenomenon in the transmission process. Stochastic nonlinearities with known statistical characteristics are utilized to describe the stochastic evolution of the complex networks. We aim to design a finite-horizon estimator, such that in the simultaneous presence of quantized measurements and stochastic inner coupling, the prescribed variance constraints on the estimation error and the desired H∞ performance requirements are guaranteed over a finite horizon. Sufficient conditions are established by means of a series of recursive linear matrix inequalities, and subsequently, the estimator gain parameters are derived. A simulation example is presented to illustrate the effectiveness and applicability of the proposed estimator design algorithm.

  4. Distinguishing cognitive state with multifractal complexity of hippocampal interspike interval sequences

    Directory of Open Access Journals (Sweden)

    Dustin eFetterhoff

    2015-09-01

    Full Text Available Fractality, represented as self-similar repeating patterns, is ubiquitous in nature and the brain. Dynamic patterns of hippocampal spike trains are known to exhibit multifractal properties during working memory processing; however, it is unclear whether the multifractal properties inherent to hippocampal spike trains reflect active cognitive processing. To examine this possibility, hippocampal neuronal ensembles were recorded from rats before, during and after a spatial working memory task following administration of tetrahydrocannabinol (THC, a memory-impairing component of cannabis. Multifractal detrended fluctuation analysis was performed on hippocampal interspike interval sequences to determine characteristics of monofractal long-range temporal correlations (LRTCs, quantified by the Hurst exponent, and the degree/magnitude of multifractal complexity, quantified by the width of the singularity spectrum. Our results demonstrate that multifractal firing patterns of hippocampal spike trains are a marker of functional memory processing, as they are more complex during the working memory task and significantly reduced following administration of memory impairing THC doses. Conversely, LRTCs are largest during resting state recordings, therefore reflecting different information compared to multifractality. In order to deepen conceptual understanding of multifractal complexity and LRTCs, these measures were compared to classical methods using hippocampal frequency content and firing variability measures. These results showed that LRTCs, multifractality, and theta rhythm represent independent processes, while delta rhythm correlated with multifractality. Taken together, these results provide a novel perspective on memory function by demonstrating that the multifractal nature of spike trains reflects hippocampal microcircuit activity that can be used to detect and quantify cognitive, physiological and pathological states.

  5. Designing molecular complexes using free-energy derivatives from liquid-state integral equation theory

    Science.gov (United States)

    Mrugalla, Florian; Kast, Stefan M.

    2016-09-01

    Complex formation between molecules in solution is the key process by which molecular interactions are translated into functional systems. These processes are governed by the binding or free energy of association which depends on both direct molecular interactions and the solvation contribution. A design goal frequently addressed in pharmaceutical sciences is the optimization of chemical properties of the complex partners in the sense of minimizing their binding free energy with respect to a change in chemical structure. Here, we demonstrate that liquid-state theory in the form of the solute-solute equation of the reference interaction site model provides all necessary information for such a task with high efficiency. In particular, computing derivatives of the potential of mean force (PMF), which defines the free-energy surface of complex formation, with respect to potential parameters can be viewed as a means to define a direction in chemical space toward better binders. We illustrate the methodology in the benchmark case of alkali ion binding to the crown ether 18-crown-6 in aqueous solution. In order to examine the validity of the underlying solute-solute theory, we first compare PMFs computed by different approaches, including explicit free-energy molecular dynamics simulations as a reference. Predictions of an optimally binding ion radius based on free-energy derivatives are then shown to yield consistent results for different ion parameter sets and to compare well with earlier, orders-of-magnitude more costly explicit simulation results. This proof-of-principle study, therefore, demonstrates the potential of liquid-state theory for molecular design problems.

  6. Designing molecular complexes using free-energy derivatives from liquid-state integral equation theory.

    Science.gov (United States)

    Mrugalla, Florian; Kast, Stefan M

    2016-09-01

    Complex formation between molecules in solution is the key process by which molecular interactions are translated into functional systems. These processes are governed by the binding or free energy of association which depends on both direct molecular interactions and the solvation contribution. A design goal frequently addressed in pharmaceutical sciences is the optimization of chemical properties of the complex partners in the sense of minimizing their binding free energy with respect to a change in chemical structure. Here, we demonstrate that liquid-state theory in the form of the solute-solute equation of the reference interaction site model provides all necessary information for such a task with high efficiency. In particular, computing derivatives of the potential of mean force (PMF), which defines the free-energy surface of complex formation, with respect to potential parameters can be viewed as a means to define a direction in chemical space toward better binders. We illustrate the methodology in the benchmark case of alkali ion binding to the crown ether 18-crown-6 in aqueous solution. In order to examine the validity of the underlying solute-solute theory, we first compare PMFs computed by different approaches, including explicit free-energy molecular dynamics simulations as a reference. Predictions of an optimally binding ion radius based on free-energy derivatives are then shown to yield consistent results for different ion parameter sets and to compare well with earlier, orders-of-magnitude more costly explicit simulation results. This proof-of-principle study, therefore, demonstrates the potential of liquid-state theory for molecular design problems.

  7. Obtaining of mullite by fast burning from bentonite clays from Paraiba state, BR; Obtencao de mulita por queima rapida a partir de argilas bentonitas paraibanas

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, J.; Rocha, A.I.O.; Oliveira, S.S.; Neves, G.A.; Lira, H.L.; Santana, L.N.L. [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Dept. de Engenharia de Materiais; Menezes, R.R., E-mail: josileido@yahoo.com.br, E-mail: lisiane@dema.ufcg.edu.br [Universidade Federal da Paraiba (UFPB), PB (Brazil). Dept. de Engenharia de Materiais

    2012-07-01

    Bentonite clays are aluminium-silicates that when heated turn into mullite. The sintering of mullite obtained from these mineral clays by quick microwaves heating comes up as an alternative process for mullite powders synthesis. The use of quick heating on ceramics nanopowders synthesis is a recent technology that is being successfully used on synthesis with microwaves and synthesis process by combustion. The quick microwaves heating enables adding heat quickly and equally, accelerating the nucleation kinetics and the development of the mullite stage. Thus, the purpose of this work is to analyze the effect of the microwaves heating process variables, analyzing the influence of the applied power and of the heating rate on the mullite powders obtaining from bentonite clays. The clays have been favored and submitted to the following characterizations: chemical granulometric and mineralogically. Subsequently, the clays have been delaminated aiming deagglomeration and separation of the thinner fractions and submitted to granulometric and mineralogical characterization. The synthesis has been realized on a domestic microwaves oven. The obtained powders have been characterized by X-ray diffraction. The results showed that the applied power variation and the sintering time are fundamental on the obtaining of mullite powders. (author)

  8. Calculation of Vibrational and Electronic Excited-State Absorption Spectra of Arsenic-Water Complexes Using Density Functional Theory

    Science.gov (United States)

    2016-06-03

    IR and UV-visible ranges. The absorption spectrum corresponding to excitation states of As-H2O complexes consisting of relatively small numbers of...complexes consisting of relatively small numbers of water molecules using DFT and TD- DFT. Calculation of excited state resonance structure using DFT and TD...absorption spectra. A significant aspect of using DFT and TD-DFT for the calculation of absorption spectra is that it adopts the perspective of computational

  9. Flora of the State of Paraíba, Brazil: Loranthaceae Juss.

    Directory of Open Access Journals (Sweden)

    Gabriella Carla Leite de Vasconcelos

    2015-08-01

    Full Text Available The family Loranthaceae Juss., characterized by its parasitic habit, is rarely studied in Brazil. Current research provides a taxonomic survey of Loranthaceae in the State of Paraiba, northeastern Brazil, in which ten species belonging to four genera have been recorded: Passovia (one species, Psittacanthus (two species, Pusillanthus (one species and Struthanthus (six species. Struthanthus concinnus Mart. was found for the first time in the state of Paraíba. A key to the species identification and taxonomic descriptions is presented, with images, geographic distribution and host data.

  10. HARDWARE AND SOFTWARE COMPLEX FOR FUNCTIONAL STATE MONITORING OF MOTHER AND FETUS

    Directory of Open Access Journals (Sweden)

    I. V. Tolmachyov

    2014-01-01

    Full Text Available Text abstract Mother’s and fetus’s health are very important in present time. With timely diagnosis perinatal pathology, birth injuries, antenatal stillbirths and newborn perinatal death can be prevented. At the moment in the world there are no complexes which enable monitoring of the fetus without any risk to his health. So the main aim of this work is development of hardware and software system to assess the functional status of the mother and fetus by the analysis of the signals recorded from the abdominal electrodes.Objectives:1 to formulate the requirements to noninvasive monitoring system and functional state assessment of mother and fetus.2 to develop algorithms and software for monitoring system and functional state assessment of mother and fetus.3 to determine fetus functional state at 32–33 week in women with uncomplicated pregnancies and in women with placental insufficiency in the compensation stage and subcompensation.The system concept is based on fetal heart rate recognition and analysis. Fetal heart rate has been extracted from the mixed signals received from abdominal electrodes. This technique is passive for a body so there is no research time limit. Device for simultaneous registration of fetal and maternal electrocardiogram is high sensitive bioamplifier with low level of intrinsic noises, high input resistance and suppression of inphase noises more than 80 DB. Digital processing of a signal is carried out by microcontroller of the registration module and personal computer. Preprocessing is carried out in microcontroller by receiving signals from the analog-to-digital converter on the increased sampling rate, digital filtering, decimation.With the help of the developed complex two-stage study was conducted. At first stage the fetal cardiointervalogram (i.e. fetus heartbeat period and the distribution pattern of these intervals in time was studied. Second stage was carried out to search additional criteria of fetal

  11. Intercalation complex of proflavine with DNA: Structure and dynamics by solid-state NMR

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Pei; Juang, Chilong; Harbison, G.S. (State Univ. of New York, Stony Brook (USA))

    1990-07-06

    The structure of the complex formed between the intercalating agent proflavine and fibrous native DNA was studied by one- and two-dimensional high-resolution solid-state nuclear magnetic resonance (NMR). Carbon-13-labeled proflavine was used to show that the drug is stacked with the aromatic ring plane perpendicular to the fiber axis and that it is essentially immobile. Natural abundance carbon-13 NMR of the DNA itself shows that proflavine binding does not change the puckering of the deoxyribose ring. However, phosphorus-31 NMR spectra show profound changes in the orientation of the phosphodiester grouping on proflavine binding, with some of the phosphodiesters tilting almost parallel to the helix axis, and a second set almost perpendicular. The first group to the phosphodiesters probably spans the intercalation sites, whereas the tilting of the second set likely compensates for the unwinding of the DNA by the intercalator.

  12. Effects of External Magnetic Fields on the Excited States of (ND)8 Metal Complexes.

    Science.gov (United States)

    Helms, Charles Alan

    Large changes in the steady state emissions and lifetimes as a function of external magnetic field strength have been observed for (nd)^8 mononuclear and binuclear complexes. These unusually pronounced effects are attributed to a field-induced symmetry reduction leading to a relaxation of transition dipole selection rules. Both spin-orbit coupling and magnetic field strength appear to play a role in determining the magnitude of the observed effect. A theoretical model has been developed to rationalize the results obtained for the Pt_2(H _2P_2O _5)_sp{4}{4-} ion. An analogous model should pertain to the mononuclear systems. Closed-shell (La(III), Lu(III)) rare earth salts of the Pt_2(H_2P _2O_5)_sp{4 }{4-} ion show the same dependence on an externally applied magnetic field as the previously examined K and Ba analogs, in all respects. However, the luminescence properties of the openshell salts are markedly different, even in the absence of a magnetic field. The zero-field phosphorescence lifetime of GdKPt_2 (H_2P_2O _5)_4 is one-tenth that of the closed-shell lifetime, but the position of the phosphorescence is unchanged from the closed-shell case. The application of an external magnetic field produces no further changes in the electronic properties of the open-shell salts. Salts containing rare earth ions with low-lying atomic states (Eu(III)) exhibit complete quenching of the Pt _2(H_2P_2 O_5)_sp{4}{4 -} phosphorescence, indicating efficient energy transfer. Results from complexes containing rare earth ions are analyzed in terms of an angular momentum coupling scheme. A recently published derivation of basis functions for the Pt_2(H_2 P_2O_5)_sp {4}{4-} ion including spin-orbit interactions was repeated and confirmed.

  13. Influence of Copper Oxidation State on the Bonding and Electronic Structure of Cobalt-Copper Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Eisenhart, Reed J.; Carlson, Rebecca K.; Clouston, Laura J.; Young, Jr., Victor G.; Chen, Yu-Sheng; Bill, Eckhard; Gagliardi, Laura; Lu, Connie C. (UC); (UMM); (MXPL)

    2016-03-04

    Heterobimetallic complexes that pair cobalt and copper were synthesized and characterized by a suite of physical methods, including X-ray diffraction, X-ray anomalous scattering, cyclic voltammetry, magnetometry, electronic absorption spectroscopy, electron paramagnetic resonance, and quantum chemical methods. Both Cu(II) and Cu(I) reagents were independently added to a Co(II) metalloligand to provide (py3tren)CoCuCl (1-Cl) and (py3tren)CoCu(CH3CN) (2-CH3CN), respectively, where py3tren is the triply deprotonated form of N,N,N-tris(2-(2-pyridylamino)ethyl)amine. Complex 2-CH3CN can lose the acetonitrile ligand to generate a coordination polymer consistent with the formula “(py3tren)CoCu” (2). One-electron chemical oxidation of 2-CH3CN with AgOTf generated (py3tren)CoCuOTf (1-OTf). The Cu(II)/Cu(I) redox couple for 1-OTf and 2-CH3CN is reversible at -0.56 and -0.33 V vs Fc+/Fc, respectively. The copper oxidation state impacts the electronic structure of the heterobimetallic core, as well as the nature of the Co–Cu interaction. Quantum chemical calculations showed modest electron delocalization in the (CoCu)+4 state via a Co–Cu σ bond that is weakened by partial population of the Co–Cu σ antibonding orbital. By contrast, no covalent Co–Cu bonding is predicted for the (CoCu)+3 analogue, and the d-electrons are fully localized at individual metals.

  14. Crystallizing Vanadium Pentoxide Nanostructures in the Solid-State Using Modified Block Copolymer and Chitosan Complexes

    Directory of Open Access Journals (Sweden)

    C. Diaz

    2015-01-01

    Full Text Available A systematic study of the synthesis of V2O5 nanostructured materials using macromolecular PS-co-4-PVP·(VCl3y and chitosan·(VCl3y complexes is presented. It is demonstrated that various coordination degrees of the metal into the polymeric chain specifically influence the product formation after pyrolysis. PS-co-4-PVP·(VCl3y and chitosan·(VCl3y complexes were prepared by simple coordination reaction of VCl3 with the respective polymer in molar ratios 1 : 1, 1 : 5, and 1 : 10 metal/polymer and characterized by elemental analysis, IR spectroscopy, and TGA/DSC analysis. Solid-state thermolysis of these precursors at several temperatures under air results in nanostructured V2O5 using all precursors. The size and shape of the nanostructured V2O5 depend on the nature of the polymer. For the chitosan·(VCl3y precursors sub-10 nm nanocrystals are formed. The calcination process, involved in the preparation method, produces V2O5 with photoluminescence in the visible light region, suggesting the possible application in oxygen sensing devices.

  15. Generalized coherent states for time-dependent and nonlinear Hamiltonian operators via complex Riccati equations

    Science.gov (United States)

    Castaños, Octavio; Schuch, Dieter; Rosas-Ortiz, Oscar

    2013-02-01

    Based on the Gaussian wave packet solution for the harmonic oscillator and the corresponding creation and annihilation operators, a generalization is presented that also applies for wave packets with time-dependent width as they occur for systems with different initial conditions, time-dependent frequency or in contact with a dissipative environment. In all these cases, the corresponding coherent states, position and momentum uncertainties and quantum mechanical energy contributions can be obtained in the same form if the creation and annihilation operators are expressed in terms of a complex variable that fulfils a nonlinear Riccati equation which determines the time-evolution of the wave packet width. The solutions of this Riccati equation depend on the physical system under consideration and on the (complex) initial conditions and have close formal similarities with general superpotentials leading to isospectral potentials in supersymmetric quantum mechanics. The definition of the generalized creation and annihilation operator is also in agreement with a factorization of the operator corresponding to the Ermakov invariant that exists in all cases considered.

  16. Enhancement of Vibronic and Ground-State Vibrational Coherences in 2D Spectra of Photosynthetic Complexes

    CERN Document Server

    Chenu, Aurélia; Kauffmann, Harald F; Mančal, Tomáš

    2013-01-01

    A vibronic-exciton model is applied to investigate the mechanism of enhancement of coherent oscillations due to mixing of electronic and nuclear degrees of freedom recently proposed as the origin of the long-lived oscillations in 2D spectra of the FMO complex [Christensson et al. J. Phys. Chem. B 116 (2012) 7449]. We reduce the problem to a model BChl dimer to elucidate the role of resonance coupling, site energies, nuclear mode and energy disorder in the enhancement of vibronic-exciton and ground-state vibrational coherences, and to identify regimes where this enhancement is significant. For a heterodimer representing the two coupled BChls 3 and 4 of the FMO complex, the initial amplitude of the vibronic-exciton and vibrational coherences are enhanced by up to 15 and 5 times, respectively, compared to the vibrational coherences in the isolated monomer. This maximum initial amplitude enhancement occurs when there is a resonance between the electronic energy gap and the frequency of the vibrational mode. The b...

  17. Resting state fMRI entropy probes complexity of brain activity in adults with ADHD.

    Science.gov (United States)

    Sokunbi, Moses O; Fung, Wilson; Sawlani, Vijay; Choppin, Sabine; Linden, David E J; Thome, Johannes

    2013-12-30

    In patients with attention deficit hyperactivity disorder (ADHD), quantitative neuroimaging techniques have revealed abnormalities in various brain regions, including the frontal cortex, striatum, cerebellum, and occipital cortex. Nonlinear signal processing techniques such as sample entropy have been used to probe the regularity of brain magnetoencephalography signals in patients with ADHD. In the present study, we extend this technique to analyse the complex output patterns of the 4 dimensional resting state functional magnetic resonance imaging signals in adult patients with ADHD. After adjusting for the effect of age, we found whole brain entropy differences (P=0.002) between groups and negative correlation (r=-0.45) between symptom scores and mean whole brain entropy values, indicating lower complexity in patients. In the regional analysis, patients showed reduced entropy in frontal and occipital regions bilaterally and a significant negative correlation between the symptom scores and the entropy maps at a family-wise error corrected cluster level of Pentropy is a useful tool in revealing abnormalities in the brain dynamics of patients with psychiatric disorders.

  18. Ab initio potential energy surface and bound states for the Kr-OCS complex.

    Science.gov (United States)

    Feng, Eryin; Sun, Chunyan; Yu, Chunhua; Shao, Xi; Huang, Wuying

    2011-09-28

    The first ab initio potential energy surface of the Kr-OCS complex is developed using the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)]. The mixed basis sets, aug-cc-pVTZ for the O, C, and S atom, and aug-cc-pVQZ-PP for the Kr atom, with an additional (3s3p2d1f) set of midbond functions are used. A potential model is represented by an analytical function whose parameters are fitted numerically to the single point energies computed at 228 configurations. The potential has a T-shaped global minimum and a local linear minimum. The global minimum occurs at R = 7.146 a(0), θ = 105.0° with energy of -270.73 cm(-1). Bound state energies up to J = 9 are calculated for three isotopomers (82)Kr-OCS, (84)Kr-OCS, and (86)Kr-OCS. Analysis of the vibrational wavefunctions and energies suggests the complex can exist in two isomeric forms: T-shaped and quasi-linear. The calculated transition frequencies and spectroscopic constants of the three isotopomers are in good agreement with the experimental values.

  19. A steady-state saturation model to determine the subsurface travel time (STT in complex hillslopes

    Directory of Open Access Journals (Sweden)

    T. Sabzevari

    2010-06-01

    Full Text Available The travel time of subsurface flow in complex hillslopes (hillslopes with different plan shape and profile curvature is an important parameter in predicting the subsurface flow in catchments. This time depends on the hillslopes geometry (plan shape and profile curvature, soil properties and climate conditions. The saturation capacity of hillslopes affect the travel time of subsurface flow. The saturation capacity, and subsurface travel time of compound hillslopes depend on parameters such as soil depth, porosity, soil hydraulic conductivity, plan shape (convergent, parallel or divergent, hillslope length, profile curvature (concave, straight or convex and recharge rate to the groundwater table. An equation for calculating subsurface travel time for all complex hillslopes was presented. This equation is a function of the saturation zone length (SZL on the surface. Saturation zone length of the complex hillslopes was calculated numerically by using the hillslope-storage kinematic wave equation for subsurface flow, so an analytical equation was presented for calculating the saturation zone length of the straight hillslopes and all plan shapes geometries. Based on our results, the convergent hillslopes become saturated very soon and they showed longer SZL with shorter travel time compared to the parallel and divergent ones. The subsurface average flow rate in convergent hillslopes is much less than the divergent ones in the steady state conditions. Concerning to subsurface travel time, convex hillslopes have more travel time in comparison to straight and concave hillslopes. The convex hillslopes exhibit more average flow rate than concave hillslopes and their saturation capacity is very low. Finally, the effects of recharge rate variations, average bedrock slope and soil depth on saturation zone extension were investigated.

  20. Disrupting neural activity related to awake-state sharp wave-ripple complexes prevents hippocampal learning

    Directory of Open Access Journals (Sweden)

    Miriam Shirin Nokia

    2012-12-01

    Full Text Available Oscillations in hippocampal local-field potentials reflect the crucial involvement of the hippocampus in memory trace formation: theta (4-8 Hz oscillations and ripples (~200 Hz occurring during sharp waves are thought to mediate encoding and consolidation, respectively. During sharp wave-ripple complexes (SPW-Rs, hippocampal cell firing closely follows the pattern that took place during the initial experience, most likely reflecting replay of that event. Disrupting hippocampal ripples using electrical stimulation either during training in awake animals or during sleep after training retards spatial learning. Here, adult rabbits were trained in trace eyeblink conditioning, a hippocampus-dependent associative learning task. A bright light was presented to the animals during the inter-trial interval, when awake, either during SPW-Rs or irrespective of their neural state. Learning was particularly poor when the light was presented following SPW-Rs. While the light did not disrupt the ripple itself, it elicited a theta-band oscillation, a state that does not usually coincide with SPW-Rs. Thus, it seems that consolidation depends on neuronal activity within and beyond the hippocampus taking place immediately after, but by no means limited to, hippocampal SPW-Rs.

  1. Steady-state ab initio laser theory for complex gain media

    CERN Document Server

    Cerjan, Alexander; Stone, A Douglas

    2014-01-01

    We derive and test a generalization of Steady-State Ab Initio Laser Theory (SALT) to treat complex gain media. The generalized theory (C-SALT) is able to treat atomic and molecular gain media with diffusion and multiple lasing transitions, and semiconductor gain media in the free carrier approximation including fully the effect of Pauli blocking. The key assumption of the theory is stationarity of the level populations, which leads to coupled self-consistent equations for the populations and the lasing modes that fully include the effects of openness and non-linear spatial hole-burning. These equations can be solved efficiently for the steady-state lasing properties by a similar iteration procedure as in SALT, where a static gain medium with a single transition is assumed. The theory is tested by comparison to much less efficient Finite Difference Time Domain (FDTD) methods and excellent agreement is found. Using C-SALT to analyze the effects of varying gain diffusion constant we demonstrate a cross-over betw...

  2. Complex Type 2 Reactions in Three Patients with Hansen's Disease from a Southern United States Clinic.

    Science.gov (United States)

    Leon, Kristoffer E; Salinas, Jorge L; McDonald, Robert W; Sheth, Anandi N; Fairley, Jessica K

    2015-11-01

    In non-endemic countries, leprosy, or Hansen's disease (HD), remains rare and is often underrecognized. Consequently, the literature is currently lacking in clinical descriptions of leprosy complications in the United States. Immune-mediated inflammatory states known as reactions are common complications of HD. Type 1 reactions are typical of borderline cases and occur in 30% of patients and present as swelling and inflammation of existing skin lesions, neuritis, and nerve dysfunction. Type 2 reactions are systemic events that occur at the lepromatous end of the disease spectrum, and typical symptoms include fever, arthralgias, neuritis, and classic painful erythematous skin nodules known as erythema nodosum leprosum. We report three patients with lepromatous leprosy seen at a U.S. HD clinic with complicated type 2 reactions. The differences in presentations and clinical courses highlight the complexity of the disease and the need for increased awareness of unique manifestations of lepromatous leprosy in non-endemic areas. © The American Society of Tropical Medicine and Hygiene.

  3. Steady-state ab initio laser theory for complex gain media.

    Science.gov (United States)

    Cerjan, Alexander; Chong, Y D; Stone, A Douglas

    2015-03-09

    We derive and test a generalization of the steady-state ab initio laser theory (SALT) to treat complex gain media. The generalized theory (C-SALT) is able to treat atomic and molecular gain media with diffusion and multiple lasing transitions, and semiconductor gain media in the free carrier approximation including fully the effect of Pauli blocking. The key assumption of the theory is stationarity of the level populations, which leads to coupled self-consistent equations for the populations and the lasing modes that fully include the effects of openness and non-linear spatial hole-burning. These equations can be solved efficiently for the steady-state lasing properties by a similar iteration procedure as in SALT, where a static gain medium with a single transition is assumed. The theory is tested by comparison to much less efficient finite difference time domain (FDTD) methods and excellent agreement is found. Using C-SALT to analyze the effects of varying gain diffusion constant we demonstrate a cross-over between the regime of strong spatial hole burning with multimode lasing to a regime of negligible spatial hole burning, leading to gain-clamping, and single mode lasing. The effect of spatially inhomogeneous pumping combined with diffusion is also studied and a relevant length scale for spatial inhomogeneity to persist under these conditions is determined. For the semiconductor gain model, we demonstrate the frequency shift due to Pauli blocking as the pumping strength changes.

  4. The Road to C4 Photosynthesis: Evolution of a Complex Trait via Intermediary States.

    Science.gov (United States)

    Schlüter, Urte; Weber, Andreas P M

    2016-05-01

    C4 photosynthesis enables high photosynthetic energy conversion efficiency as well as high nitrogen and water use efficiencies. Given the multitude of biochemical, structural and molecular changes in comparison with C3 photosynthesis, it appears unlikely that such a complex trait would evolve in a single step. C4 photosynthesis is therefore believed to have evolved from the ancestral C3 state via intermediary stages. Consequently, the identification and detailed characterization of plant species representing transitory states between C3 and C4 is important for the reconstruction of the sequence of evolutionary events, especially since C4 evolution occurred in very different phylogenetic backgrounds. There is also significant interest in engineering of C4 or at least C4-like elements into C3 crop plants. A detailed and mechanistic understanding of C3-C4 intermediates is likely to provide guidance for the experimental design of such approaches. Here we provide an overview on the most relevant results obtained on C3-C4 intermediates to date. Recent knowledge gains in this field will be described in more detail. We thereby concentrate especially on biochemical and physiological work. Finally, we will provide a perspective and outlook on the continued importance of research on C3-C4 intermediates.

  5. Fully delocalized (ethynyl)(vinyl)phenylene bridged triruthenium complexes in up to five different oxidation states.

    Science.gov (United States)

    Wuttke, Evelyn; Pevny, Florian; Hervault, Yves-Marie; Norel, Lucie; Drescher, Malte; Winter, Rainer F; Rigaut, Stéphane

    2012-02-01

    Triruthenium [(dppe)(2)Ru{-C≡C-1,4-C(6)H(2)-2,5-R(2)-CH═CH-RuCl(CO)(P(i)Pr(3))(2)}(2)](n+) (4a, R = H; 4b, R = OMe) containing unsymmetrical (ethynyl)(vinyl)phenylene bridging ligands and displaying five well-separated redox states (n = 0-4) are compared to their bis(alkynyl)ruthenium precursors (dppe)(2)Ru{-C≡C-1,4-C(6)H(2)-2,5-R(2)-C≡CR'} (2a,b: R' = TMS; 3a,b: R' = H) and their symmetrically substituted bimetallic congeners, complexes {Cl(dppe)(2)Ru}(2){μ-C≡C-1,4-C(6)H(2)-2,5-R(2)-C≡C} (A(a), R = H; A(b), R = OMe) and {RuCl(CO)(P(i)Pr(3))(2)}(2){μ-CH═CH-1,4-C(6)H(2)-2,5-R(2)-CH═CH} (V(a), R = H; V(b), R = OMe) as well as the mixed (ethynyl)(vinyl)phenylene bridged [Cl(dppe)(2)Ru-C≡C-1,4-C(6)H(4)-CH═CH-RuCl(CO)(P(i)Pr(3))(2)] (M(a)). Successive one-electron transfer steps were studied by means of cyclic voltammetry, EPR and UV-vis-NIR-IR spectroelectrochemistry. These studies show that the first oxidation mainly involves the central bis(alkynyl) ruthenium moiety with only limited effects on the appended vinyl ruthenium moieties. The second to fourth oxidations (n = 2, 3, 4) involve the entire carbon-rich conjugated path of the molecule with an increased charge uniformly distributed between the two arms of the molecules, including the terminal vinyl ruthenium sites. In order to assess the charge distribution, we judiciously use (13)CO labeled analogues to distinguish stretching vibrations due to the acetylide triple bonds and the intense and charge-sensitive Ru(CO) IR probe in different oxidation states. The comparison between complex pairs 4a,b(n+) (n = 0-3), A(a,b)(n+) and V(a,b)(n+) (n = 0-2) serves to elucidate the effect of the methoxy donor substituents on the redox and spectroscopic properties of these systems in their various oxidation states and on the metal/ligand contributions to their frontier orbitals.

  6. Studies on solid state synthesis and the oxygenation property of cobalt(II) Schiff base (vanilline polyamine)complexes

    Institute of Scientific and Technical Information of China (English)

    XIAO Furong; CHEN Lu; WANG Jide; WU Ronglan; YUE Fan; LI Jing

    2007-01-01

    Three new cobalt complexes were synthesized by solid-state reaction at room temperature and the resultant Co complexes reacted with two equivalent oxygen molecules at room temperature to produce the oxygenated complexes 2H2O (L3=N, N'-bis(4-hydroxyl-3-methoxy-benzyltetraethylenepentamine).The oxygenated complexes were characterized by elemental analysis,IR (Infrared),1H-NMR (Nuclear Magnetic Resonance),and UV-Vis (Ultraviolet Visual) spectrometry,and TG/DTA (Thermogravimetry/Differential Thermal Analysis) analysis,and molar conductance.The coordinated oxygen contents in the oxygenated complexes were also determined by weight method.It was supposed that only one O2 molecule coordinated to the Co ion forming a superoxo type oxygenated complex.

  7. Solid-State Synthesis, Characterization, and Biological Activity of the Bioinorganic Complex of Aspartic Acid and Arsenic Triiodide

    Directory of Open Access Journals (Sweden)

    Guo-Qing Zhong

    2013-01-01

    Full Text Available The bioinorganic complex of aspartic acid and arsenic triiodide was synthesized by a solid-state reaction at room temperature. The formula of the complex is AsI3[HOOCCH2CH(NH2COOH]2.5. The crystal structure of the complex belongs to monoclinic system with lattice parameters: a=1.0019 nm, b=1.5118 nm, c=2.1971 nm, and β=100.28°. The infrared spectra can demonstrate the complex formation between the arsenic ion and aspartic acid, and the complex may be a dimer with bridge structure. The result of primary biological test indicates that the complex possesses better biological activity for the HL-60 cells of the leukemia than arsenic triiodide.

  8. Direct observation of intersystem crossing in a thermally activated delayed fluorescence copper complex in the solid state.

    Science.gov (United States)

    Bergmann, Larissa; Hedley, Gordon J; Baumann, Thomas; Bräse, Stefan; Samuel, Ifor D W

    2016-01-01

    Intersystem crossing in thermally activated delayed fluorescence (TADF) materials is an important process that controls the rate at which singlet states convert to triplets; however, measuring this directly in TADF materials is difficult. TADF is a significant emerging technology that enables the harvesting of triplets as well as singlet excited states for emission in organic light emitting diodes. We have observed the picosecond time-resolved photoluminescence of a highly luminescent, neutral copper(I) complex in the solid state that shows TADF. The time constant of intersystem crossing is measured to be 27 picoseconds. Subsequent overall reverse intersystem crossing is slow, leading to population equilibration and TADF with an average lifetime of 11.5 microseconds. These first measurements of intersystem crossing in the solid state in this class of mononuclear copper(I) complexes give a better understanding of the excited-state processes and mechanisms that ensure efficient TADF.

  9. Solid-state NMR analysis of a complex crystalline phase of ronacaleret hydrochloride.

    Science.gov (United States)

    Vogt, Frederick G; Williams, Glenn R; Strohmeier, Mark; Johnson, Matthew N; Copley, Royston C B

    2014-08-28

    A crystalline phase of the pharmaceutical compound ronacaleret hydrochloride is studied by solid-state nuclear magnetic resonance (SSNMR) spectroscopy and single-crystal X-ray diffraction. The crystal structure is determined to contain two independent cationic molecules and chloride anions in the asymmetric unit, which combine with the covalent structure of the molecule to yield complex SSNMR spectra. Experimental approaches based on dipolar correlation, chemical shift tensor analysis, and quadrupolar interaction analysis are employed to obtain detailed information about this phase. Density functional theory (DFT) calculations are used to predict chemical shielding and electric field gradient (EFG) parameters for comparison with experiment. (1)H SSNMR experiments performed at 16.4 T using magic-angle spinning (MAS) and homonuclear dipolar decoupling provide information about hydrogen bonding and molecular connectivity that can be related to the crystal structure. (19)F and (13)C assignments for the Z' = 2 structure are obtained using DFT calculations, (19)F homonuclear dipolar correlation, and (13)C-(19)F heteronuclear dipolar correlation experiments. (35)Cl MAS experiments at 16.4 T observe two chlorine sites that are assigned using calculated chemical shielding and EFG parameters. SSNMR dipolar correlation experiments are used to extract (1)H-(13)C, (1)H-(15)N, (1)H-(19)F, (13)C-(19)F, and (1)H-(35)Cl through-space connectivity information for many positions of interest. The results allow for the evaluation of the performance of a suite of SSNMR experiments and computational approaches as applied to a complex but typical pharmaceutical solid phase.

  10. A novel method of complex evaluation of meibomian glands morphological and functional state

    Directory of Open Access Journals (Sweden)

    V. N. Trubilin

    2014-01-01

    Full Text Available A novel method that provides complex assessment of meibomian glands morphological and functional state — biometry of meibomian glands — was developed. The results of complex examination (including meibomian glands biometry, correlation analysis data and clinical findings demonstrate direct association between the objective (i.e., meibomian glands dysfunction by biomicroscopy, tear film break-up time / TBUT, symptomatic TBUT, compression testing and subjective signs of meibomian glands dysfunction (patient’s complaints and the parameters of meibomian glands biometry. High direct correlation between biometrical index and compression test result was revealed (p = 0.002, Spearman’s rank correlation coefficient = 0.6644. Meibomian glands dysfunction is characterized by biometric parameters abnormalities, i.e., dilatation of meibomian glands orifices, decrease of distance between meibomian glands orifices, partial or total atrophy of meibomian glands (even up to gland collapse with its visual reduction and increase of distance between the glands. The suppression of inflammatory process and the recovery of meibomian glands secretion improve biometric parameters and result in the opening of meibomian glands orifices, liquefaction of clogs, evacuation of meibomian glands secretion, narrowing of meibomian glands orifices and increase of distance between them. The proposed method expands the armamentarium of meibomian glands dysfunction and lipid-deficient dry eye diagnosing. Meibomian glands biometry can be applied in specialized ophthalmological hospitals and outpatient departments. It is a simple procedure of short duration that does not require any special equipment or professional skills. Meibomian glands biometry enables to prescribe pathogenically targeted therapy and to improve quality of life. 

  11. The role of spin state on the local atomic and electronic structures of some metalloporphyrin complexes

    Energy Technology Data Exchange (ETDEWEB)

    Suchkova, S A; Soldatov, A [Southern Federal University, Sorge str. 5, 344090 Rostov-on-Don (Russian Federation); Dziedzik-Kocurek, K [Yagellonian University, Krakow (Poland); Stillman, M J, E-mail: suchkova_sv@inbox.r [University of Western Ontario, London, Ontario (Canada)

    2009-11-15

    The Porphyrin molecule is an archetypal metalloorganic complex, which shows up in many biochemical molecules like chlorophyll, haemoglobin and cytochrome. The prospect of switching the spin in the metalloporphyrin ring is a particularly interesting one, as this could be used, for example, for spin-dependent electric transport through biomolecular devices. These molecules can be used in various applications like optical switches, information storage and non linear optics. Here, we study the molecular spin state of chloro-hemin, hemin cyanide and hemin carbonyl molecules by ADF code. Chloro-hemin has been studied by analyzing the Fe K-edge X-Ray Absorption Near Edge Structure (XANES) spectra. At first stage of investigation we assume an approximate initial geometry, then we perform the geometry optimization with different molecular spin states and search for configuration with minimal total energy with the use of Density Functional Theory (ADF 2008). The results of geometry optimization of chloro-hemin molecule performed with the GGA OPBE functional showed that configuration with total spin S = 5/2 has minimal total energy. This configuration corresponds well with the geometry structure obtained via X-Ray diffraction method (Fe-N-N angle is 13.3{sup 0}). The similar calculations that were carried out for hemin carbonyl and hemin cyanide molecules showed that for these structures minimal energy is found to be for S = 1/2. The experimental Fe K-XANES spectra of the investigated compound have been collected. The theoretical analysis of the experimental data has been performed on the basis of finite difference method (FDMnes2007 program code).

  12. Effects of excited state mixing on transient absorption spectra in dimers Application to photosynthetic light-harvesting complex II

    CERN Document Server

    Valkunas, L; Trinkunas, G; Müller, M G; Holzwarth, A R

    1999-01-01

    The excited state mixing effect is taken into account considering the difference spectra of dimers. Both the degenerate (homo) dimer as well as the nondegenerate (hetero) dimer are considered. Due to the higher excited state mixing with the two-exciton states in the homodimer, the excited state absorption (or the difference spectrum) can be strongly affected in comparison with the results obtained in the Heitler-London approximation. The difference spectrum of the heterodimer is influenced by two resonance effects (i) mixing of the ground state optical transitions of both monomers in the dimer and (ii) mixing of the excited state absorption of the excited monomer with the ground state optical transition in the nonexcited monomer. These effects have been tested by simulating the difference absorption spectra of the light-harvesting complex of photosystem II (LHC II) experimentally obtained with the 60 fs excitation pulses at zero delay times and various excitation wavelengths. The pairs of coupled chlorophylls...

  13. [Triatoma vandae sp.n. of the oliveirai complex from the State of Mato Grosso, Brazil (Hemiptera: Reduviidae: Triatominae)].

    Science.gov (United States)

    Carcavallo, Rodolfo U; Jurberg, José; Rocha, Dayse da Silva; Galvao, Cleber; Noireau, François; Lent, Herman

    2002-07-01

    There are several specific complexes belonging to the genus Triatoma Laporte, 1832, which are generally associated to specific geographic areas. Recent publications have linked the oliveirai complex to ecosystems of Mato Grosso, which are also present in other Brazilian states and even in other bordering countries as eastern Paraguay. The study of the abundant material collected during the last years allowed the description of several new species of the oliveirai complex: T. jurbergi Carcavallo, Galvão Lent, 1998; T. baratai Carcavallo Jurberg, 2000 and T. klugi Carcavallo, Jurberg, Lent Galvão, 2001. Another new species belonging to the same complex is described here as T. vandae sp.n. It originates from the state of Mato Grosso, and has been reared in the insectary of the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Departamento de Entomologia, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro.

  14. Efeito da Gliricidia sepium sobre nutrientes do solo, microclima e produtividade do milho em sistema agroflorestal no Agreste Paraibano Effects of Gliricidia sepium on soil nutrients, microclimate and maize yield in an agroforestry system in semi-arid Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    Aldrin Martin Pérez Marin

    2006-06-01

    Northeastern semi-arid region of Brazil because of its good development under water stress conditions. However, little information is available on the effects of the introduction of this species into regional agroecosystems. The objective of the present study was to evaluate the influence of the distance of Gliricidia sepium plants on the characteristics of maize crop, soil properties and microclimate conditions in the semi-arid region of Paraiba, Brazil. The study was conducted in the Esperança County, Paraíba State, Brazil., where G. sepium trees were planted on a 0.5 ha field in 1996. The spacing used was 6 m between rows and 1 m between plants within the rows. In 2002, four 48 m² plots were established within this field. Within each plot, three sampling positions were established: (1 under tree crowns in the rows (0 m; (2 1 m apart from tree rows; and (3 3 m apart from the tree rows. The experiment had a randomized block design with four replications. Litterfall dry matter amounted to 1.390 kg ha-1 under the trees and decreased to 270 kg ha-1 at a distance of 3 m from the trees. Soil P, K and light fraction of organic matter were significantly greater under the trees as compared to those between the tree rows. Soil and air monthly minimum temperature averages were not influenced by the distance from the trees. However, soil and air monthly maximum temperature averages were 6 and 2 °C lower under the trees, respectively. Soil moisture was significantly lower under the trees as compared to positions 1 and 3 m away from tree rows. Maize grain and straw yields as well as nutrient accumulation were higher under the trees and decreased with increasing the distance from the trees.

  15. Avaliação hematologica de caprinos exóticos e nativos no semi-árido paraibano Hematological evaluation of exotic and native goats in Paraiba's Semi-arid

    Directory of Open Access Journals (Sweden)

    Elisângela Maria Nunes da Silva

    2008-04-01

    Full Text Available O presente experimento foi conduzido na Estação Experimental de Pendência, pertencente à Empresa Estadual de Pesquisa Agropecuária da Paraíba S.A. (EMEPA, localizada no município de Soledade -PB, na microrregião do Curimataú Ocidental, Semi-árido da Paraíba. Objetivou-se com este trabalho realizar uma avaliação hematológica de caprinos exóticos e nativos criados no Semi-árido paraibano. Foram utilizadas 40 fêmeas das raças Boer, Savana, Anglo-Nubiana e Moxotó, sendo 10 de cada raça, com idade média de cinco meses, distribuídos num delineamento inteiramente casualizado, com 10 repetições, criadas em sistema semi-intensivo. Foram registradas as variáveis ambientais na sombra e no sol às 9:00 e às 15:00 horas, com auxílio de termômetros de máxima e mínima temperaturas, bulbo seco e bulbo úmido e de globo negro, e determinado o índice de temperatura do globo negro e umidade (ITGU, na sombra e no sol. Para a realização da hematimetria e leucometria foram coletadas amostras de 5 mL de sangue de cada animal, em tubo à vácuo com anticoagulante. A análise de variância revelou efeito de raça para os seguintes parâmetros hematológicos: eritrócitos, hematócrito e hemoglobina. Para o número de eritrócitos houve diferença significativa entre as raças Savana, Anglo-Nubiana e Moxotó, mas a raça Boer não diferiu em relação às raças Savana e Anglo-Nubiana. Houve efeito significativo para a variável leucócitos, tendo as raças Savana e Moxotó diferido das raças Boer e Anglo-Nubiana. Embora fatores como raça e ambiente influenciem sobre os parâmetros hematológicos, todas as raças apresentaram médias dentro dos limites normais para a espécie, demonstrando estarem bem adaptadas às condições climáticas do semi-árido.The present experiment was carried out in the Experimental Station of Dispute, belonging to the State Company of Agricultural Research of Paraíba S.A. (EMEPA, located in the municipal

  16. INVESTMENT ACTIVITY OF AGRIBUSINESS IN THE AGROINDUSTRIAL COMPLEX REGION, AS ONE OF THE ELEMENTS OF THE FINANCIAL SECURITY OF THE AGRO-INDUSTRIAL COMPLEX OF THE STATE

    Directory of Open Access Journals (Sweden)

    Olga Nikolaevna Uglitskikh

    2015-09-01

    Full Text Available The developed economic-political situation around of Russia, specifies an indispensability of support of agricultural commodity producers as from their financial well-being, investment activity the financial security of agrarian and industrial complex of the state depends. Limitation of own financial resources at agrarians does not allow them to realize independently conceived projects. Studying of questions of formation and functioning of investment activity in agriculture of Stavropol Territory and an assessment of investment projects offered to reali-zation, have allowed to analyse investment activity of agrarian and industrial complex of region up to the introduction of Russia into WTO and in conditions of its membership. By results of the lead assessment the administrative areas of region showing the greatest investment activity, threats of a financial security of agrarian and industrial complex of region not putting by the activity have been revealed. It is drawn a conclusion on influence West-American sanctions on financial without-danger agra-rian and industrial complex of the state and the responsibility сельхозтоваропроизводителей about delivery of agricultural production in necessary volume and import substitution.

  17. Natural radionuclides in the Brazilian coast region: 1. Estuarine complex Cananeia-Iguape, Sao Paulo State

    Energy Technology Data Exchange (ETDEWEB)

    Franca, E.J. de; Ferreira, Fabiano S.; Silva Neto, Paulo C.; Farias, Emerson E.G. de; Figueira, Rubens C.L.; Ribeiro, Andreza P., E-mail: ejfranca@cnen.gov.br, E-mail: biologofabiano10@gmail.com, E-mail: ptpoli@yahoo.com.br, E-mail: emersonemiliano@yahoo.com.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2015-07-01

    Mangrove forests are of utmost important ecosystems for biogeochemical transport processes in a global scale because of the preferential transport via sediments and organic matter from continents to oceans. Such ecosystems are the richest biodiversity areas, in which bioaccumulation of chemical substances can be expected for some species, in this case, there is a lack of knowledge of natural radionuclides accumulation in mangrove vegetation. This work encompasses the first results obtained for the Estuarine Complex Cananeia-Iguape, a peculiar coast area of the Sao Paulo State, Brazil. In 2011, leaf samples of Rhyzophora mangle and Laguncularia racemosa trees with perimeter at the breast height higher than 15 cm were collected in the conservation unit Parque Estadual Ilha do Cardoso. Sample preparation consisted of leaf washing, oven-drying, milling in porcelain mortar at the particle size lower than 0.5 mm. Portions of 10 g were transferred to polyethylene vials of appropriate geometry for the analysis by high resolution gamma-ray spectrometry. Reference materials were analyzed together to evaluate the quality of the analytical procedure. K-40 was preferentially allocated in leaves. Some accumulation in leaves was noticed for Pb-210 and Ac-228 depending on the species, indicating differences of radionuclide distribution in the mangrove vegetation. (author)

  18. Molecular characterization of the Trichomonas gallinae morphologic complex in the United States.

    Science.gov (United States)

    Gerhold, Richard W; Yabsley, Michael J; Smith, Autumn J; Ostergaard, Elissa; Mannan, William; Cann, Jeff D; Fischer, John R

    2008-12-01

    Forty-two Trichomonas gallinae isolates were molecularly characterized to determine whether isolates differed in genetic sequence of multiple gene targets depending on host species or geographical location. The 5.8S ribosomal RNA (rRNA) and flanking internal transcribed spacer (ITS) gene regions were amplified by polymerase chain reaction, and the sequences were analyzed phylogenetically. The results of the sequence analysis strongly suggest at least 2 species may exist within the T. gallinae morphologic complex. Based on ITS sequences, one group demonstrated high nucleotide identity to the 3 T. gallinae sequences available in GenBank, whereas the second group was more closely related to T. vaginalis (98%) than to T. gallinae (92%). Two common ground-dove (Columbina passerina) isolates shared a 95% identity with T. vaginalis and a 92% identity with T. gallinae and T. tenax. Sequence analysis of both the 18S rRNA and alpha-tubulin genes from a subset of the isolates supports the 5.8S-ITS sequence results. All of the T. vaginalis-like isolates originated from Arizona, California, or Texas, whereas T. gallinae isolates were found in all sampled states. Both T. vaginalis-like and T. gallinae isolates were involved in trichomoniasis outbreaks in California and Arizona.

  19. STATE OF THE ART TECHNIQUES USED FOR NOISE SOURCE IDENTIFICATION ON COMPLEX BODIES

    Directory of Open Access Journals (Sweden)

    Corneliu STOICA

    2010-03-01

    Full Text Available Over the last few decades, many approaches have been undertaken in order to asses detailed noise source identification on complex bodies, i.e. aircrafts, cars, machinery. Noise source identification implies to accurately obtain the position and frequency of the dominant noise sources. There are cases where traditional testing methods can not be applied at all or their use involves some limitations. Optical systems used for near field analysis require a line of sight that may not be available. The state-of-the-art technology for this purpose is the use of a large number of microphones whose signals are acquired simultaneously, i.e. microphone phased array. Due to the excessive cost of the instruments and the data acquisition system required, the implementation of this technology was restricted to governmental agencies (NASA, DLR and big companies such as Boeing and Airbus. During the past years, this technique was developed in wind tunnels and some universities to perform noise source identification on scale airframes, main landing gear models, and aerodynamic profiles (used on airplanes, helicopter rotors and wind mills.

  20. Decamethylytterbocene Complexes of Bipyridines and Diazabutadienes: Multiconfigurational Ground States and Open-Shell Singlet Formation

    Energy Technology Data Exchange (ETDEWEB)

    Booth, Corwin H.; Walter, Marc D.; Kazhdan, Daniel; Hu, Yung-Jin; Lukens, Wayne W.; Bauer, Eric D.; Maron, Laurent; Eisenstein, Odile; Andersen, Richard A.

    2009-04-22

    Partial ytterbium f-orbital occupancy (i.e., intermediate valence) and open-shell singlet formation are established for a variety of bipyridine and diazabutadiene adducts with decamethylytterbocene, (C5Me5)2Yb, abbreviated as Cp*2Yb. Data used to support this claim include ytterbium valence measurements using Yb LIII-edge X-ray absorption near-edge structure spectroscopy, magnetic susceptibility, and complete active space self-consistent field (CASSCF) multiconfigurational calculations, as well as structural measurements compared to density functional theory calculations. The CASSCF calculations indicate that the intermediate valence is the result of a multiconfigurational ground-state wave function that has both an open-shell singlet f13(?*)1, where pi* is the lowest unoccupied molecular orbital of the bipyridine or dpiazabutadiene ligands, and a closed-shell singlet f14 component. A number of other competing theories for the unusual magnetism in these materials are ruled out by the lack of temperature dependence of the measured intermediate valence. These results have implications for understanding chemical bonding not only in organolanthanide complexes but also for f-element chemistry in general, as well as understanding magnetic interactions in nanoparticles and devices.

  1. Decamethylytterbocene complexes of bipyridines and diazabutadines: multiconfigurational ground states and open-shell singlet formation

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Eric D [Los Alamos National Laboratory; Booth, C H [LBNL; Walter, M D [LBNL; Kazhdan, D [LBNL; Hu, Y - J [LBNL; Lukens, Wayne [LBNL; Maron, Laurent [INSA TOULOUSE; Eisentein, Odile [UNIV MONTPELLIER 2; Anderson, Richard [LBNL

    2009-01-01

    Partial ytterbium f-orbital occupancy (i.e. intermediate valence) and open-shell singlet Draft 12/formation are established for a variety of bipyridine and diazabutadiene adducts to decamethylytterbocene, (C{sub 5}Me{sub 5}){sub 2}Yb or Cp*{sub 2}Yb. Data used to support this claim includes ytterbium valence measurements using Yb Lm-edge x-ray absorption near-edge structure (XANES) spectroscopy, magnetic susceptibility and Complete Active Space Self-Consistent Field (CASSCF) multi configurational calculations, as well as structural measurements compared to density-functional theory (DFT) calculations. The CASSCF calculations indicate that the intermediate valence is the result of a multiconfigurational ground state wave function that has both an open-shell singlet f{sup 13} and a closed-shell singlet f{sup 14} component. A number of other competing theories for the unusual magnetism in these materials are ruled out by the presence of intermediate valence and its lack of any significant temperature dependence. These results have implications for understanding chemical bonding not only in organolanthanide complexes, but also for organometallic chemistry in general, as well as understanding magnetic interactions in nanopartic1es and devices.

  2. IMPROVING THE MECHANISMS OF STATE REGULATION OF THE AGRO-INDUSTRIAL COMPLEX OF THE KRASNODAR REGION IN MODERN CONDITIONS

    Directory of Open Access Journals (Sweden)

    Artemova E. I.

    2016-03-01

    Full Text Available The article examines features of the functioning of the agro-industrial complex of Russia and the Krasnodar region in the economic crisis. It substantiates the urgency of adaptation of state regulation of agro-industrial complex mechanisms to modern economic realities, we have disclosed functions and principles for the development of regional policy strategy in the agricultural sector. It is proved, that the system of state regulation of regional agro-industrial complex should correlate with the priorities of the development of its main component - agriculture and to promote structural reforms in the agricultural sector, enhance its innovation and investment potential and maintain the social orientation of the agrarian reforms. Improving the mechanisms of state support of the agro-industrial complex of Russia and the Krasnodar region requires a special approach in relation to the country's membership in the World Trade Organization. Due to this, we have proposed the adjustment of state support instruments of domestic agro-industrial complex, which involves the use of priority measures of the "green box", including an increase in funding for research in agriculture, development of an effective institutional environment, which will stimulate the efficiency and competitiveness of the agricultural sector

  3. Theoretical study on OH{sup −} site and electronic spin state of oxygen-evolving complex in photosystem II at the dark S{sub 1} state

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, Makoto; Ogata, Koji; Nakamura, Shinichiro [RIKEN Research Cluster for Innovation, Nakamura Laboratory, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Uchida, Waka [Department of Biomolecular Engineering, Tokyo Institute of Technology, B-70, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503 (Japan)

    2013-12-10

    Possible protonation and electronic-spin states of oxygen-evolving complex (OEC) in photosystem II have been investigated by using QM(DFT-UB3LYP)/MM(Amber) calculation, in order to elucidate which OEC state satisfies the known experimental results at the dark stable state (S{sub 1}), i.e. OEC involves Mn{sub 4}(III{sub 2},IV{sub 4})-cluster and a S=0 state as the lowest energy electronic-spin state at S{sub 1}. The configuration of Mn oxidation numbers and the lowest energy spin state within the Mn{sub 4}-cluster depend on the protonation state of one oxo-anion bridging three Mn ions. When all water-ligands and oxo-bridges form H{sub 2}O and O{sup 2−}, respectively, the resulting OEC model involved Mn{sub 4}(III{sub 2},IV{sub 2})-cluster and one S=0 state as the lowest energy spin state. To rationalize the O{sup 2−}-bridge model at S{sub 1} state, a new H{sup +}-release scheme during the H{sub 2}O-splitting reaction is proposed.

  4. Bounded H∞ synchronization and state estimation for discrete time-varying stochastic complex networks over a finite horizon.

    Science.gov (United States)

    Shen, Bo; Wang, Zidong; Liu, Xiaohui

    2011-01-01

    In this paper, new synchronization and state estimation problems are considered for an array of coupled discrete time-varying stochastic complex networks over a finite horizon. A novel concept of bounded H(∞) synchronization is proposed to handle the time-varying nature of the complex networks. Such a concept captures the transient behavior of the time-varying complex network over a finite horizon, where the degree of bounded synchronization is quantified in terms of the H(∞)-norm. A general sector-like nonlinear function is employed to describe the nonlinearities existing in the network. By utilizing a time-varying real-valued function and the Kronecker product, criteria are established that ensure the bounded H(∞) synchronization in terms of a set of recursive linear matrix inequalities (RLMIs), where the RLMIs can be computed recursively by employing available MATLAB toolboxes. The bounded H(∞) state estimation problem is then studied for the same complex network, where the purpose is to design a state estimator to estimate the network states through available output measurements such that, over a finite horizon, the dynamics of the estimation error is guaranteed to be bounded with a given disturbance attenuation level. Again, an RLMI approach is developed for the state estimation problem. Finally, two simulation examples are exploited to show the effectiveness of the results derived in this paper.

  5. Carotenoid to chlorophyll energy transfer in the peridinin–chlorophyll-a–protein complex involves an intramolecular charge transfer state

    Science.gov (United States)

    Zigmantas, Donatas; Hiller, Roger G.; Sundström, Villy; Polívka, Tomáš

    2002-01-01

    Carotenoids are, along with chlorophylls, crucial pigments involved in light-harvesting processes in photosynthetic organisms. Details of carotenoid to chlorophyll energy transfer mechanisms and their dependence on structural variability of carotenoids are as yet poorly understood. Here, we employ femtosecond transient absorption spectroscopy to reveal energy transfer pathways in the peridinin–chlorophyll-a–protein (PCP) complex containing the highly substituted carotenoid peridinin, which includes an intramolecular charge transfer (ICT) state in its excited state manifold. Extending the transient absorption spectra toward near-infrared region (600–1800 nm) allowed us to separate contributions from different low-lying excited states of peridinin. The results demonstrate a special light-harvesting strategy in the PCP complex that uses the ICT state of peridinin to enhance energy transfer efficiency. PMID:12486228

  6. [Design of software and hardware complex of automated systems for the management of the State Sanitary and Epidemiological Surveillance].

    Science.gov (United States)

    Mel'nichenko, P I; Muzychenko, F V; Malinovskiĭ, A A; Leont'ev, L Iu; Ustiukhin, N V

    2005-05-01

    A new information system (IS) - the software and hardware complex for controlling the state sanitary-and-epidemiological inspection (SSEI) was created. The system represents the aggregate of automated working places of RF MD chief state sanitary physician arid specialists from the department of state sanitary-and-epidemiological inspection of the Main Military Medical Headquarters. They interact through communications with working places of specialists from SSEI Main Center, chief state sanitary physicians from the Armed Forces, military districts (fleets) and RFAF CSSEI. The special software provides automation of the following technological processes: operative sanitary-and epidemiological and epidemiological monitoring; the epidemiological analysis of infectious diseases; the evaluation of quality and efficiency of sanitary-and epidemiological work. At present the complex works in the regime of experimental exploitation when the adjustment of communications and special software is performed.

  7. Design, synthesis and excited-state properties of mononuclear Ru(II) complexes of tridentate heterocyclic ligands.

    Science.gov (United States)

    Pal, Amlan K; Hanan, Garry S

    2014-09-07

    Artificial photosynthetic systems that contain light-harvesting coordination complexes may one day replace conventional non-renewable sources of energy with renewable solar energy sources. Light-Harvesting Complexes (LHC) are important components of natural photosynthetic systems and are also sought after in artificial systems as well. Polynuclear photoactive complexes are therefore very attractive, and those based on stereogenic [Ru(2,2'-bipyridine)3](2+) are photophysically appealing, but difficult to obtain in a stereochemically pure form. On the other hand, polynuclear complexes based on the achiral [Ru(2,2':6',2''-terpyridine)2](2+) motif are easy to synthesise, however, these complexes are devoid of attractive excited-state properties. Hence strategies to increase the r.t. excited-state lifetime of these complexes would be of practical importance in vectorial electron and/or electron transfer in various optoelectronic applications. This tutorial review will report on the sophisticated synthetic strategies currently in use to enhance the photophysical properties of mononuclear Ru(II) complexes of tridentate ligands at room temperature.

  8. In situ solid-state NMR spectroscopy of protein in heterogeneous membranes: the baseplate antenna complex of Chlorobaculum tepidum.

    Science.gov (United States)

    Kulminskaya, Natalia V; Pedersen, Marie Ø; Bjerring, Morten; Underhaug, Jarl; Miller, Mette; Frigaard, Niels-Ulrik; Nielsen, Jakob T; Nielsen, Niels Chr

    2012-07-01

    A clever combination: an in situ solid-state NMR analysis of CsmA proteins in the heterogeneous environment of the photoreceptor of Chlorobaculum tepidum is reported. Using different combinations of 2D and 3D solid-state NMR spectra, 90 % of the CsmA resonances are assigned and provide on the basis of chemical shift data information about the structure and conformation of CsmA in the CsmA-bacteriochlorophyll a complex.

  9. Importance of out-of-state spin-orbit coupling for slow magnetic relaxation in mononuclear Fe(II) complexes.

    Science.gov (United States)

    Lin, Po-Heng; Smythe, Nathan C; Gorelsky, Serge I; Maguire, Steven; Henson, Neil J; Korobkov, Ilia; Scott, Brian L; Gordon, John C; Baker, R Tom; Murugesu, Muralee

    2011-10-12

    Two mononuclear high-spin Fe(II) complexes with trigonal planar ([Fe(II)(N(TMS)(2))(2)(PCy(3))] (1) and distorted tetrahedral ([Fe(II)(N(TMS)(2))(2)(depe)] (2) geometries are reported (TMS = SiMe(3), Cy = cyclohexyl, depe = 1,2-bis(diethylphosphino)ethane). The magnetic properties of 1 and 2 reveal the profound effect of out-of-state spin-orbit coupling (SOC) on slow magnetic relaxation. Complex 1 exhibits slow relaxation of the magnetization under an applied optimal dc field of 600 Oe due to the presence of low-lying electronic excited states that mix with the ground electronic state. This mixing re-introduces orbital angular momentum into the electronic ground state via SOC, and 1 thus behaves as a field-induced single-molecule magnet. In complex 2, the lowest-energy excited states have higher energy due to the ligand field of the distorted tetrahedral geometry. This higher energy gap minimizes out-of-state SOC mixing and zero-field splitting, thus precluding slow relaxation of the magnetization for 2.

  10. Multi-path variational transition state theory for chemical reaction rates of complex polyatomic species: ethanol + OH reactions.

    Science.gov (United States)

    Zheng, Jingjing; Truhlar, Donald G

    2012-01-01

    Complex molecules often have many structures (conformations) of the reactants and the transition states, and these structures may be connected by coupled-mode torsions and pseudorotations; some but not all structures may have hydrogen bonds in the transition state or reagents. A quantitative theory of the reaction rates of complex molecules must take account of these structures, their coupled-mode nature, their qualitatively different character, and the possibility of merging reaction paths at high temperature. We have recently developed a coupled-mode theory called multi-structural variational transition state theory (MS-VTST) and an extension, called multi-path variational transition state theory (MP-VTST), that includes a treatment of the differences in the multi-dimensional tunneling paths and their contributions to the reaction rate. The MP-VTST method was presented for unimolecular reactions in the original paper and has now been extended to bimolecular reactions. The MS-VTST and MP-VTST formulations of variational transition state theory include multi-faceted configuration-space dividing surfaces to define the variational transition state. They occupy an intermediate position between single-conformation variational transition state theory (VTST), which has been used successfully for small molecules, and ensemble-averaged variational transition state theory (EA-VTST), which has been used successfully for enzyme kinetics. The theories are illustrated and compared here by application to three thermal rate constants for reactions of ethanol with hydroxyl radical--reactions with 4, 6, and 14 saddle points.

  11. Diversidade de Scarabaeidae s. str. (Coleoptera da Reserva Biológica Guaribas, Mamanguape, Paraíba, Brasil: uma comparação entre Mata Atlântica e Tabuleiro Nordestino Diversity of Scarabaeidae s. str. (Coleoptera in the Reserva Biológica Guaribas, Mamanguape, Paraiba, Brazil: a comparison between Atlantic Forest and northeast's Tabuleiro

    Directory of Open Access Journals (Sweden)

    Ana Aline Endres

    2007-03-01

    Full Text Available Os Scarabaeidae consomem fezes e carcaças de grandes vertebrados. Comunidades de escarabeídeos foram comparadas entre áreas de Mata e Tabuleiro da Reserva Biológica Guaribas, Mamanguape, Paraíba. As amostragens foram realizadas mensalmente durante o período de Novembro/2001 a Abril/2002 em áreas de Tabuleiro e Mata. Para coleta dos insetos foram utilizadas 24 armadilhas pitfall iscadas, 12 em cada área, sendo seis iscadas com fezes humanas e seis com fígado apodrecido. Na área de Mata foram coletados 15 espécies e 1298 indivíduos. Na área de Tabuleiro, 25 espécies e 2235 indivíduos. Onze espécies ocorrem conjuntamente nos dois ambientes, sendo 14 registradas apenas para o Tabuleiro e 4 para a Mata. Dichotomius sericeus (Harold, 1867 foi a espécie mais abundante nas duas áreas. A área de Tabuleiro apresentou maior riqueza, entretanto a Mata apresentou maior dominância. O compartilhamento de espécies comuns entre a Mata e o Tabuleiro confere a estes ambientes similaridade moderada.Diversity of Scarabaeidae s. str. (Coleoptera in the Reserva Biológica Guaribas, Mamanguape, Paraiba, Brazil: a comparison between Atlantic Forest and northeast's Tabuleiro. Scarabaeid beetles consume dung and carcasses of large vertebrates. Guilds of scarabeids were compared between Forest and Tabuleiro at the Reserva Biológica Guaribas, Mamanguape, in the state of Paraíba. Samples were collected monthly from November 2001 to April 2002 in Forest and Tabuleiro. Insects were collected by using 24 pitfall-traps, 12 in each area, with six traps baited with human excrement and six with rotten liver. Fifteen species and 1298 specimens were collected in the Forest and 25 species and 2235 specimens in the Tabuleiro. Eleven species occurred in both areas, whereas 14 were found only in the Tabuleiro and four in the Forest. Dichotomius sericeus (Harold, 1867 was the most abundant species in the two areas. The Tabuleiro was the most species-rich; however

  12. Rovibrational states of the H2O-H2 complex: An ab initio calculation

    Science.gov (United States)

    van der Avoird, Ad; Nesbitt, David J.

    2011-01-01

    All bound rovibrational levels of the H2O-H2 dimer are calculated for total angular momentum J = 0-5 on two recent intermolecular potential surfaces reported by Valiron et al. [J. Chem. Phys. 129, 134306 (2008)] and Hodges et al. [J. Chem. Phys. 120, 710 (2004)] obtained through ab initio calculations. The method used handles correctly the large amplitude internal motions in this complex; it involves a discrete variable representation of the intermolecular distance coordinate R and a basis of coupled free rotor wave functions for the hindered internal rotations and the overall rotation of the dimer. The basis is adapted to the permutation symmetry associated with the para/ortho (p/o) nature of both H2O and H2 as well as to inversion symmetry. Dimers containing oH2 are more strongly bound than dimers with pH2, as expected, with dissociation energies D_0 of 33.57, 36.63, 53.60, and 59.04 cm^{-1}for pH2O-pH2, oH2O-pH2, pH2O-oH2, and oH2O-oH2, respectively, on the potential of Valiron et al. that corresponds to a binding energy D_e of 235.14 cm^{-1}. Rovibrational wave functions are computed as well and the nature of the bound states in the four different dimer species is discussed. Converged rovibrational levels on both potentials agree well with the high-resolution spectrum reported by Weida and Nesbitt [J. Chem. Phys. 110, 156 (1999)]; the hindered internal rotor model that was used to interpret this spectrum is qualitatively correct.

  13. Calculation of the scalar curvature for the four state complex spin model and investigation of its behaviour

    Directory of Open Access Journals (Sweden)

    T. Mardani

    2005-06-01

    Full Text Available  In various statistical mechanical models, introduction of a metric into space of prameters gives a new perspective to the phase structure. In this paper, the scalar curvature R of this metric for a one dimensional four-state complex spin model is calculated. It is shown that this parameter has a similar behaviour to the Ising and Potts models.

  14. Accessing the Long-Lived Triplet Excited States in Transition-Metal Complexes: Molecular Design Rationales and Applications.

    Science.gov (United States)

    Cui, Xiaoneng; Zhao, Jianzhang; Mohmood, Zafar; Zhang, Caishun

    2016-02-01

    Transition-metal complex triplet photosensitizers are versatile compounds that have been widely used in photocatalysis, photovoltaics, photodynamic therapy (PDT) and triplet-triplet annihilation (TTA) upconversion. The principal photophysical processes in these applications are the intermolecular energy transfer or electron transfer. One of the major challenges facing these triplet photosensitizers is the short triplet-state lifetime, which is detrimental to the above-mentioned photophysical processes. In order to address this challenge, transition-metal complexes showing long-lived triplet excited states are highly desired. This review article summarizes the development of this fascinating area, including the molecular design rationales, the principal photophysical properties, and the applications of these complexes in PDT and TTA upconversion.

  15. Solid-state and solution-state coordination chemistry of lanthanide(III) complexes with α-hydroxyisobutyric acid.

    Science.gov (United States)

    Chen, Xiao-Yan; Goff, George S; Ewing, William C; Scott, Brian L; Runde, Wolfgang

    2012-12-17

    Despite the wide range of applications of α-hydroxyisobutyric acid (HIBA) in biochemical processes, pharmaceutical formulations, and group and elemental separations of lanthanides and actinides, the structures and geometries of lanthanide-HIBA complexes are still not well understood. We reacted HIBA with lanthanides in aqueous solution at pH = 5 and synthesized 14 lanthanide-HIBA complexes of the formula [Ln(HIBA)(2)(H(2)O)(2)](NO(3))·H(2)O (Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11), Tm (12), Yb (13), Lu (14)), isolating single crystals (1-7, 10, and 11) and powders (8, 9, and 12-14). Both single-crystal and powder X-ray diffraction studies reveal a two-dimensional extended structure across the entire lanthanide series. The environment around the eight-coordinated Ln(III) atom is best described as a distorted dodecahedron, where HIBA acts as a monoanionic tridentate ligand with one carboxylato oxygen atom and one hydroxyl oxygen atom chelating to one Ln(III) center. The carboxylato oxygen atom from a second HIBA ligand bridges to a neighboring Ln(III) atom to form a two-dimensional extended structure. While the coordination mode for HIBA is identical across the lanthanide series, three different structure types are found for La, Ce-Ho, and Er-Lu. Solution characterization using (13)C NMR further confirmed a single solution complex under the crystallization conditions. Raman and UV-vis-NIR absorbance and diffuse reflectance spectra of HIBA-Ln(III) complexes were also measured.

  16. Implementation of a complex multi-phase equation of state for cerium and its correlation with experiment

    Energy Technology Data Exchange (ETDEWEB)

    Cherne, Frank J [Los Alamos National Laboratory; Jensen, Brian J [Los Alamos National Laboratory; Elkin, Vyacheslav M [VNIITF

    2009-01-01

    The complexity of cerium combined with its interesting material properties makes it a desirable material to examine dynamically. Characteristics such as the softening of the material before the phase change, low pressure solid-solid phase change, predicted low pressure melt boundary, and the solid-solid critical point add complexity to the construction of its equation of state. Currently, we are incorporating a feedback loop between a theoretical understanding of the material and an experimental understanding. Using a model equation of state for cerium we compare calculated wave profiles with experimental wave profiles for a number of front surface impact (cerium impacting a plated window) experiments. Using the calculated release isentrope we predict the temperature of the observed rarefaction shock. These experiments showed that the release state occurs at different magnitudes, thus allowing us to infer where dynamic {gamma} - {alpha} phase boundary is.

  17. Chromium(0), molybdenum(0), and tungsten(0) isocyanide complexes as luminophores and photosensitizers with long-lived excited states

    Energy Technology Data Exchange (ETDEWEB)

    Bueldt, Laura A. [Institute of Inorganic Chemistry, University of Tuebingen, Auf der Morgenstelle 18, 72076, Tuebingen (Germany); Wenger, Oliver S. [Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel (Switzerland)

    2017-05-15

    Arylisocyanide complexes based on earth-abundant Group 6 d{sup 6} metals are interesting alternatives to photoactive complexes made from precious metals such as Ru{sup II}, Re{sup I}, Os{sup II}, or Ir{sup III}. Some of these complexes have long-lived {sup 3}MLCT excited states that exhibit luminescence with good quantum yields as well as nano- to microsecond lifetimes, and they are very strongly reducing. Recent studies have demonstrated that Cr{sup 0}, Mo{sup 0}, and W{sup 0} arylisocyanide complexes have great potential for applications in luminescent devices, photoredox catalysis, and dye-sensitized solar cells. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Line bundle twisted chiral de Rham complex and bound states of D-branes on toric manifolds

    Energy Technology Data Exchange (ETDEWEB)

    Parkhomenko, S.E., E-mail: spark@itp.ac.ru [Landau Institute for Theoretical Physics, 142432 Chernogolovka, Moscow region (Russian Federation); Moscow Institute of Physics and Technology, 141707 Dolgoprudny, Moscow region (Russian Federation)

    2014-04-15

    In this note we calculate elliptic genus in various examples of twisted chiral de Rham complex on two-dimensional toric compact manifolds and Calabi–Yau hypersurfaces in toric manifolds. At first the elliptic genus is calculated for the line bundle twisted chiral de Rham complex on a compact smooth toric manifold and K3 hypersurface in P{sup 3}. Then we twist chiral de Rham complex by sheaves localized on positive codimension submanifolds in P{sup 2} and calculate in each case the elliptic genus. In the last example the elliptic genus of chiral de Rham complex on P{sup 2} twisted by SL(N) vector bundle with instanton number k is calculated. In all the cases considered we find the infinite tower of open string oscillator contributions and identify directly the open string boundary conditions of the corresponding bound state of D-branes.

  19. [AIDS-complex and our Leviathan. Can and should the state educate us about AIDS?].

    Science.gov (United States)

    Sigusch, V

    1989-08-01

    Sigusch pleads for removing AIDS education from the jurisdiction of the state. He reasons that as caretaker of citizens' sexual lives the state cannot avoid consolidating their status as its subjects.

  20. Solid-state and solution-state coordination chemistry of lanthanide(III) complexes with (pyrazol-1-yl)acetic acid.

    Science.gov (United States)

    Chen, Xiao-Yan; Goff, George S; Scott, Brian L; Janicke, Michael T; Runde, Wolfgang

    2013-03-18

    As a precursor of carboxyl-functionalized task-specific ionic liquids (TSILs) for f-element separations, (pyrazol-1-yl)acetic acid (L) can be deprotonated as a functionalized pyrazolate anion to coordinate with hard metal cations. However, the coordination chemistry of L with f-elements remains unexplored. We reacted L with lanthanides in aqueous solution at pH = 5 and synthesized four lanthanide complexes of general formula [Ln(L)3(H2O)2]·nH2O (1, Ln = La, n = 2; 2, Ln = Ce, n = 2; 3, Ln = Pr, n = 2; 4, Ln = Nd, n = 1). All complexes were characterized by single crystal X-ray diffraction analysis revealing one-dimensional chain formations. Two distinct crystallographic structures are governed by the different coordination modes of carboxylate groups in L: terminal bidentate and bridging tridentate (1-3); terminal bidentate, bridging bidentate, and tridentate coordination in 4. Comparison of the solid state UV-vis-NIR diffuse reflectance spectra with solution state UV-vis-NIR spectra suggests a different species in solution and solid state. The different coordination in solid state and solution was verified by distinctive (13)C NMR signals of the carboxylate groups in the solid state NMR.

  1. Cyclotriphosphazene appended porphyrins and fulleropyrrolidine complexes as supramolecular multiple photosynthetic reaction centers: steady and excited states photophysical investigation.

    Science.gov (United States)

    Nair, Vishnu Sukumaran; Pareek, Yogita; Karunakaran, Venugopal; Ravikanth, Mangalampalli; Ajayaghosh, Ayyappanpillai

    2014-06-01

    New multiple photosynthetic reaction centers were constructed from cyclophosphazene decorated multiporphyrin chromophores and a fulleropyrrolidine having a pyridine ligand (FPY). The excited state electron transfer in the self-assembled donor-acceptor assembly was investigated by using steady state absorption and emission, time-resolved emission spectroscopy and nanosecond laser flash photolysis. The effect of metal (Zn(2+)) coordination to porphyrin units in the multiporphyrin arrays on cyclophosphazine scaffold (P3N3Zn) was studied by comparing with metal free porphyrin assembly on a cyclophosphazene scaffold (P3N3). In P3N3Zn, the decrease of absorption and fluorescence intensity and the lowering of the amplitude of longer fluorescence lifetime with increase of FPY concentration reflect the formation of a ground state complex with an association constant of ∼14,910 M(-1). When compared to the metal-free complex P3N3, the metal-coordinated derivative P3N3Zn exhibited shortening of the singlet and triplet state lifetimes and lowering of the singlet and triplet quantum yields. The cause of the decrease of the triplet quantum yields by insertion of zinc metal is discussed along with the possible non-planarity of the porphyrin ring. From the fluorescence lifetime measurements for the P3N3Zn-FPY mixture, it is proposed that self-assembly of the donor-acceptor complex leads to charge separated species with a rate constant of 7.1 × 10(9) s(-1). The decrease of triplet state intensity and lifetime of the P3N3Zn in the P3N3Zn-FPY complex from the nanosecond transient absorption studies support the occurrence of intermolecular electron transfer in the triplet state.

  2. Raman scattering and photophysics in spin-state-labile d(6) metal complexes

    NARCIS (Netherlands)

    Browne, WR; McGarvey, JJ

    2006-01-01

    In this review two areas of d(6) transition metal ion chemistry and photophysics are briefly reviewed (i) that of Ru(II)dipyridophenazine (dppz) complexes as DNA intercalators and (ii) spin crossover behavior in Fe(II) complexes. In both areas the role of Raman spectroscopy in providing information

  3. Tuning excited state isomerization dynamics through ground state structural changes in analogous ruthenium and osmium sulfoxide complexes.

    Science.gov (United States)

    Garg, Komal; Engle, James T; Ziegler, Christopher J; Rack, Jeffrey J

    2013-08-26

    The complexes [Ru(bpy)2(pyESO)](PF6)2 and [Os(bpy)2(pyESO)](PF6)2, in which bpy is 2,2'-bipyridine and pyESO is 2-((isopropylsulfinyl)ethyl)pyridine, were prepared and studied by (1)H NMR, UV-visible and ultrafast transient absorption spectroscopy, as well as by electrochemical methods. Crystals suitable for X-ray structural analysis were grown for [Ru(bpy)2(pyESO)](PF6)2. Cyclic voltammograms of both complexes provide evidence for S→O and O→S isomerization as these voltammograms are described by an ECEC (electrochemical-chemical electrochemical-chemical) mechanism in which isomerization follows Ru(2+) oxidation and Ru(3+) reduction. The S- and O-bonded Ru(3+/2+) couples appear at 1.30 and 0.76 V versus Ag/AgCl in propylene carbonate. For [Os(bpy)2(pyESO)](PF6)2, these couples appear at 0.97 and 0.32 V versus Ag/AgCl in acetonitrile, respectively. Charge-transfer excitation of [Ru(bpy)2(pyESO)](PF6)2 results in a significant change in the absorption spectrum. The S-bonded isomer of [Ru(bpy)2(pyESO)](2+) features a lowest energy absorption maximum at 390 nm and the O-bonded isomer absorbs at 480 nm. The quantum yield of isomerization in [Ru(bpy)2(pyESO)](2+) was found to be 0.58 in propylene carbonate and 0.86 in dichloroethane solution. Femtosecond transient absorption spectroscopic measurements were collected for both complexes, revealing time constants of isomerizations of 81 ps (propylene carbonate) and 47 ps (dichloroethane) in [Ru(bpy)2(pyESO)](2+). These data and a model for the isomerizing complex are presented. A striking conclusion from this analysis is that expansion of the chelate ring by a single methylene leads to an increase in the isomerization time constant by nearly two orders of magnitude.

  4. Development of Bipolar All-solid-state Lithium Battery Based on Quasi-solid-state Electrolyte Containing Tetraglyme-LiTFSA Equimolar Complex

    OpenAIRE

    Yoshiyuki Gambe; Yan Sun; Itaru Honma

    2015-01-01

    The development of high energy–density lithium-ion secondary batteries as storage batteries in vehicles is attracting increasing attention. In this study, high-voltage bipolar stacked batteries with a quasi-solid-state electrolyte containing a Li-Glyme complex were prepared, and the performance of the device was evaluated. Via the successful production of double-layered and triple-layered high-voltage devices, it was confirmed that these stacked batteries operated properly without any interna...

  5. Occurrence of new species of mealybug on cotton fields in the states of Bahia and Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Domingues da Silva

    2012-01-01

    Full Text Available The cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae has been reported occurring in several countries causing severe losses in economically important crops, including cotton. Based on information reported by farmers in the regions of the Southwest and Middle São Francisco, Bahia and also in the regions of the Agreste and Semi-arid of the Paraiba State, high infestations of cotton mealybugs have occurred in these regions during the cotton season of 2007 and 2008. The cotton mealybug was identified as P. solenopsis and this represents the first record of this insect attacking cotton in Brazil.

  6. Coupled dynamics of node and link states in complex networks: A model for language competition

    CERN Document Server

    Carro, Adrián; Miguel, Maxi San

    2016-01-01

    Inspired by language competition processes, we present a model of coupled evolution of node and link states. In particular, we focus on the interplay between the use of a language and the preference or attitude of the speakers towards it, which we model, respectively, as a property of the interactions between speakers (a link state) and as a property of the speakers themselves (a node state). Furthermore, we restrict our attention to the case of two socially equivalent languages and to socially inspired network topologies based on a mechanism of triadic closure. As opposed to most of the previous literature, where language extinction is an inevitable outcome of the dynamics, we find a broad range of possible asymptotic configurations, which we classify as: frozen extinction states, frozen coexistence states, and dynamically trapped coexistence states. Moreover, metastable coexistence states with very long survival times and displaying a non-trivial dynamics are found to be abundant. Interestingly, a system si...

  7. Synthesis of Pyridine– and Pyrazine–BF 3 Complexes and Their Characterization in Solution and Solid State

    Energy Technology Data Exchange (ETDEWEB)

    Chénard, Etienne; Sutrisno, Andre; Zhu, Lingyang; Assary, Rajeev S.; Kowalski, Jeffrey A.; Barton, John L.; Bertke, Jeffery A.; Gray, Danielle L.; Brushett, Fikile R.; Curtiss, Larry A.; Moore, Jeffrey S.

    2016-03-31

    Following the discovery of the redox-active 1,4- bis-BF3-quinoxaline complex, we undertook a structure- activity study with the objective to understand the active nature of the quinoxaline complex. Through systematic synthesis and characterization, we have compared complexes prepared from pyridine and pyrazine derivatives, as heterocyclic core analogues. This paper reports the structural requirements that give rise to the electrochemical features of the 1,4-bis-BF3-quinoxaline adduct. Using solution and solidstate NMR spectroscopy, the role of aromatic ring fusion and nitrogen incorporation in bonding and electronics was elucidated. We establish the boron atom location and its interaction with its environment from 1D and 2D solution NMR, X-ray diffraction analysis, and 11B solid-state NMR experiments. Crystallographic analysis of single crystals helped to correlate the boron geometry with 11B quadrupolar coupling constant (CQ) and asymmetry parameter (ηQ), extracted from 11B solid-state NMR spectra. Additionally, computations based on density functional theory were performed to predict electrochemical behavior of the BF3-heteroaromatic complexes. We then experimentally measured electrochemical potential using cyclic voltammetry and found that the redox potentials and CQ values are similarly affected by electronic changes in the complexes.

  8. Light-harvesting Complexes (LHCs) Cluster Spontaneously in Membrane Environment Leading to Shortening of Their Excited State Lifetimes.

    Science.gov (United States)

    Natali, Alberto; Gruber, J Michael; Dietzel, Lars; Stuart, Marc C A; van Grondelle, Rienk; Croce, Roberta

    2016-08-05

    The light reactions of photosynthesis, which include light-harvesting and charge separation, take place in the amphiphilic environment of the thylakoid membrane. The light-harvesting complex II (LHCII) is the main responsible for light absorption in plants and green algae and is involved in photoprotective mechanisms that regulate the amount of excited states in the membrane. The dual function of LHCII has been extensively studied in detergent micelles, but recent results have indicated that the properties of this complex differ in a lipid environment. In this work we checked these suggestions by studying LHCII in liposomes. By combining bulk and single molecule measurements, we monitored the fluorescence characteristics of liposomes containing single complexes up to densely packed proteoliposomes. We show that the natural lipid environment per se does not alter the properties of LHCII, which for single complexes remain very similar to that in detergent. However, we show that LHCII has the strong tendency to cluster in the membrane and that protein interactions and the extent of crowding modulate the lifetimes of the excited state in the membrane. Finally, the presence of LHCII monomers at low concentrations of complexes per liposome is discussed.

  9. Chemistry of high-oxidation-state groups V and VI complexes: Novel silyl and imido complexes and the reactions of silyl and alkyl alkylidyne complexes with oxygen

    Science.gov (United States)

    Chen, Tianniu

    This dissertation describes the synthesis and characterization of the novel early transition metal (especially group VI metals) complexes free of anionic pi-ligands such as cyclopentadienyl (Cp) and studies of their reactions with oxygen and silanes. Our study of Cp-free tungsten silyl chemistry is reported. A novel d 0 tungsten silyl complex 2 [(ButCH 2)W(=CHBut)2(SiButPh2 ) (2a) ⇌ (ButCH2)2W(≡CBu t)(SiButPh2) (2b)] and an equilibrium between 2a and 2b are described in Chapter 2. The thermodynamics of this equilibrium [DeltaH° = -0.9(0.2) kcal/mol, DeltaS° = -0.6(0.8) eu] was investigated by 1H NMR. The studies of the alpha-hydrogen exchange between 2a and 2b by 2-D EXSY experiments gave kinetic parameters of the exchange: DeltaH≠ = 17.9(1.1) kcal/mol, DeltaS≠ = 1.9(5.7) eu for the forward reaction (2a → 2b) and Delta H≠ = 18.6 (1.1) kcal/mol, DeltaS ≠ = 1.9(5.7) eu for the back reaction (2b → 2a). The reaction of O2 with silyl alkylidyne 2b [(Bu tCH2)W(=CHBut)2(SiBut Ph2) (2a) ⇌ (ButCH2)2W(≡CBu t)(SiButPh2) (2b)] is described in Chapter 3. A silyl migration product (ButCH2) 2W(=O)[=C(But)(SiButPh2)] ( 5) was characterized. A siloxy analog of 2b, (Bu tCH2)2W≡CBut(OSiBu tPh2) (6), was prepared and excluded as a possible intermediate in the formation of 5. Ab initio calculations suggested a pathway involving silyl migration in 2b to give a tungsten (IV) intermediate (ButCH 2)2W=C(But)(SiButPh2) (7) prior to the reaction with O2. A crystal structure of (Me3SiCH2)2W(=O)(=CHSiMe3)(O=PMe 3)•(Me3SiCH2)3W≡CSiMe 3 (12) was obtained from the reaction of alkyl alkylidyne (Me3SiCH2)3W≡CSiMe3 with O2 in the presence of PMe3. In Chapter 4, preparation and characterization of bis(2,6-diisopropylphenylimido)molybdenum(VI) amide and silyl complexes (ArN=)2Mo(NMe2)2 (14), (ArN=)2Mo(NMe2)[Si(SiMe3) 3] (15), (ArN=)2MoCl[N(SiMe3) 2] (16), (ArN=)2Mo(NMe2)[N(SiMe 3)2] (17), and (ArN=)2Mo(NHAr) 2 (18) are reported. In addition, new bis

  10. Effect of inclusion complexation with cyclodextrins on photostability of nifedipine in solid state.

    Science.gov (United States)

    Bayomi, Mohsen A; Abanumay, Khalid A; Al-Angary, Abdulaziz A

    2002-08-28

    Nifedipine is a highly photosensitive drug that requires restricted protection from light during manufacturing, storage and handling of its dosage forms. Inclusion complexation of nifedipine with cyclodextrins (CDs) could be advantageous in protecting the drug against the effect of light. In this study, solid inclusion complexes of nifedipine with beta-cyclodextrin (beta-CD), hydroxypropyl-beta-cyclodextrin (HP-beta-CD) and dimethyl-beta-cyclodextrin (DM-beta-CD) were prepared using the coprecipitation method. The obtained solid inclusion complexes have been confirmed by differential scanning calorimetry (DSC), X-ray diffraction and infrared spectroscopy (IR). The IR spectra indicated partial inclusion of nifedipine molecules into CD cavities through the dihydropyridine ring. Inclusion complexation was also associated with a dramatic enhancement of drug dissolution with magnitudes depended on the type of CD. The effect of exposure to fluorescent lamp and sunlight on the photodegradation of uncomplexed and complexed nifedipine was tested. Photodegradation of nifedipine was monitored using a high performance liquid chromatographic (HPLC) assay method. Inclusion complexation of nifedipine showed to retard drug photodegradation as indicated by degradation rate constant lowering with values depended on light source and type of complexing agent. This effect was the least with beta-CD compared with that of modified beta-CD. It was also interesting to notice that inclusion complexation of nifedipine offered much higher protection against the effect of fluorescent lamp than that of sunlight. The obtained results suggests that the design of solid dosage forms of nifedipine such as a fast dissolving nifedipine tablets is possible with the advantages of low required light protection.

  11. Minimal classical communication and measurement complexity for quantum information splitting of a two-qubit state

    Indian Academy of Sciences (India)

    Prasanta K Panigrahi; Siddharth Karumanchi; Sreraman Muralidharan

    2009-09-01

    We investigate the usefulness of the highly entangled five-partite cluster and Brown states for the quantum information splitting (QIS) of a special kind of two-qubit state using remote state preparation. In our schemes, the information that is to be shared is known to the sender. We show that, QIS can be accomplished with just two classical bits, as opposed to four classical bits, when the information that is to be shared is unknown to the sender. The present algorithm, demonstrated through the cluster and Brown states is deterministic as compared to the previous works in which it was probabilistic.

  12. Electronic spectra and photophysics of platinum(II) complexes with alpha-diimine ligands - Solid-state effects. I - Monomers and ligand pi dimers

    Science.gov (United States)

    Miskowski, Vincent M.; Houlding, Virginia H.

    1989-01-01

    Two types of emission behavior for Pt(II) complexes containing alpha-diimine ligands have been observed in dilute solution. If the complex also has weak field ligands such as chloride, ligand field (d-d) excited states become the lowest energy excited states. If only strong field ligands are present, a diimine 3(pi-pi/asterisk/) state becomes the lowest. In none of the cases studied did metal-to-ligand charge transfer excited state lie lowest.

  13. Complex angular momentum theory of state-to-state integral cross sections: resonance effects in the F + HD → HF(v' = 3) + D reaction.

    Science.gov (United States)

    Sokolovski, D; Akhmatskaya, E; Echeverría-Arrondo, C; De Fazio, D

    2015-07-28

    State-to-state reactive integral cross sections (ICSs) are often affected by quantum mechanical resonances, especially near a reactive threshold. An ICS is usually obtained by summing partial waves at a given value of energy. For this reason, the knowledge of pole positions and residues in the complex energy plane is not sufficient for a quantitative description of the patterns produced by resonance. Such description is available in terms of the poles of an S-matrix element in the complex plane of the total angular momentum. The approach was recently implemented in a computer code ICS_Regge, available in the public domain [Comput. Phys. Commun., 2014, 185, 2127]. In this paper, we employ the ICS_Regge package to analyse in detail, for the first time, the resonance patterns predicted for integral cross sections (ICSs) of the benchmark F + HD → HF(v' = 3) + D reaction. The v = 0, j = 0, Ω = 0 → v' = 3, j' = 0, 1, 2, and Ω' = 0, 1, 2 transitions are studied for collision energies from 58.54 to 197.54 meV. For these energies, we find several resonances, whose contributions to the ICS vary from symmetric and asymmetric Fano shapes to smooth sinusoidal Regge oscillations. Complex energies of metastable states and Regge pole positions and residues are found by Padé reconstruction of the scattering matrix elements. The accuracy of the ICS_Regge code, relation between complex energies and Regge poles, various types of Regge trajectories, and the origin of the J-shifting approximation are also discussed.

  14. Modeling inference of mental states : As simple as possbile, as complex as necessary

    NARCIS (Netherlands)

    Meijering, Ben; Taatgen, Niels; van Rijn, Hedderik; Verbrugge, Rineke

    2014-01-01

    Behavior oftentimes allows for many possible interpretations in terms of mental states, such as goals, beliefs, desires, and intentions. Reasoning about the relation between behavior and mental states is therefore considered to be an effortful process. We argue that people use simple strategies to d

  15. Solid State NMR Characterization of Complex Metal Hydrides systems for Hydrogen Storage Applications

    Directory of Open Access Journals (Sweden)

    Son-Jong Hwang

    2011-12-01

    Full Text Available Solid state NMR is widely applied in studies of solid state chemistries for hydrogen storage reactions. Use of 11B MAS NMR in studies of metal borohydrides (BH4 is mainly focused, revisiting the issue of dodecaborane formation and observation of 11B{1H} Nuclear Overhauser Effect.

  16. Solid-state NMR on complex biomolecules: novel methods and applications

    NARCIS (Netherlands)

    Nand, D.

    2011-01-01

    Solid-state NMR (ssNMR) represents a versatile technique in providing atomic-resolution information without the need for crystals or fast molecular motion required for X-ray crystallography and solution-state NMR, respectively. Recent past has witnessed the ability of this technique in providing det

  17. A steady-state analytical slope stability model for complex hillslopes

    NARCIS (Netherlands)

    Talebi, A.; Troch, P.A.; Uijlenhoet, R.

    2008-01-01

    This paper presents a steady-state analytical hillslope stability model to study the role of topography on rain-induced shallow landslides. We combine a bivariate continuous function of the topographic surface, a steady-state hydrological model of hillslope saturated storage, and the infinite slope

  18. A steady-state analytical slope stability model for complex hillslopes

    NARCIS (Netherlands)

    Talebi, A.; Troch, P.A.; Uijlenhoet, R.

    2008-01-01

    This paper presents a steady-state analytical hillslope stability model to study the role of topography on rain-induced shallow landslides. We combine a bivariate continuous function of the topographic surface, a steady-state hydrological model of hillslope saturated storage, and the infinite slope

  19. Fractal complexity in spontaneous EEG metastable-state transitions: new vistas on integrated neural dynamics

    Directory of Open Access Journals (Sweden)

    Paolo Allegrini

    2010-09-01

    Full Text Available Resting-state EEG signals undergo Rapid Transition Processes (RTPs that glue otherwise stationary epochs. We study the fractal properties of RTPs in space and time, supporting the hypothesis that the brain works at a critical state. We discuss how the global intermittent dynamics of collective excitations is linked to mentation, namely non-constrained non-task-oriented mental activity.

  20. IMPROVING THE EFFICIENCY OF THE STATE FINANCIAL CONTROL IN THE SPHERE OF HIGH-TECH MILITARY-INDUSTRIAL COMPLEX

    Directory of Open Access Journals (Sweden)

    Anzhela Zakhitovna Namitulina

    2016-01-01

    Full Text Available The presented research topic is particularly relevant due to the high value and the need to strengthen fi nancial control for the development of the military-industrial complex (MIC, to ensure the country's economic security, preservation and development of scientifi c and technical potential. The urgency of acquiring those aspects of economic relations which are connected with the supply the export of high-tech military products in a limited budget funding State should have levers of infl uence on the functioning of the military-industrial complex, the ability to pursue an independent foreign military-technical policy. In the new economic conditions, it became necessary to address the problems of fi nancial security of the defense-industrial complex, in order to strengthen the independence and security of Russia, as well as the need to give priority nature of the measures of state control in the economy related to the implementation of the defense order, ie, in the sphere of military-industrial complex. At the present stage of economic development of Russia, the rate of growth of the national economy largely depends on what the situation is in the military-industrial complex (MIC. This is due to the fact that the defense industry is the most high-quality, high-tech economy. It concentrated the largest part of the Russian potential, the best staff of scientists and experts. Products and DIC technology widely used in other industries. The modern military-industrial complex produces a signifi cant part of civil production. DIC integration with civilian industries – it is also a technological basis for solving the basic problems currently facing the Russian economy, and, above all, the basis of the formation of a new technological basis for the development of high technology and competitive products, which determines the pace of scientifi c and technological progress and the growth of the national economy. Objectives. The aim of the paper is the

  1. Clearing the haze: the complexities and challenges of research on state marijuana laws.

    Science.gov (United States)

    Choo, Esther K; Emery, Sherry L

    2017-04-01

    As states increasingly liberalize marijuana laws, high-quality research is needed that will inform the public and policymakers about the health and societal impact of these laws. However, there are many challenges to studying marijuana policy, including the heterogeneity of the drug and its use, the variability in the laws and their implementation from state to state, the need to capture a wide variety of relevant outcomes, and the poorly understood influence of marijuana commercialization. Furthermore, current instruments generally fail to distinguish between types of users and lack accurate and detailed measures of use. This review provides a background on marijuana laws in the United States and an overview of existing policy research, discusses methodological considerations when planning analysis of state marijuana laws, and highlights specific topics needing further development and investigation. © 2016 New York Academy of Sciences.

  2. Radical reactions of diamine bis(phenolate) vanadium(iii) complexes. Solid state binding of O2 to form a vanadium(v) peroxo complex.

    Science.gov (United States)

    Barroso, Sónia; Coelho, Ana M; Adão, Pedro; Calhorda, Maria José; Martins, Ana M

    2017-07-25

    [VCl3(THF)3] reacted with the sodium salt of a tripodal diamine bisphenolate ligand precursor Na2L2 to give a paramagnetic d(2) complex [V(L2)Cl] (2). The reaction of 2 with oxygen is strongly dependent on the experimental conditions, affording [VO(L2)Cl] (6) or [V(η(2)-O2)(L2)Cl] (7). The formation of 7 involves the direct addition of O2 to V(iii) in the solid state with oxidation to V(v) without significantly disturbing the structure of 2. DFT calculations showed that compound 7 is an intermediate in the formation of 6 from 2. The reaction involves the cleavage of the η(1)-O-O bond in a proposed dimeric species. The overall reaction of 2 moles of vanadium(iii), complex 2, and one mole of O2 to yield two moles of product 6 is a favourable process with ΔG298 = -38.3 kcal mol(-1). 7 is the first non-oxido peroxidovanadium(v) complex obtained directly from the reaction of a crystal and the second example of a structurally characterized complex of that type. Reactions of V(L1)Cl (1) and V(L2)Cl (2) with one equivalent of the nitroxyl radical TEMPO in toluene also result in the formation of oxido V(v) complexes, VO(L1)Cl (5) and VO(L2)Cl (6). The reaction of VO(O(i)Pr)3 with Na2L2 afforded [VO(L2)(O(i)Pr)] (8) in high yield. A major isomer having the V[double bond, length as m-dash]O moiety in the equatorial plane was characterised by X-ray diffraction although solution NMR data showed the presence of a minor species with the oxido ligand trans to the tripodal nitrogen, as in 6. Complexes 6 and 8 are very active and selective sulfoxidation catalysts of thioanisole, but no enantiomeric excess was obtained.

  3. Visualization of the eEF2-80S ribosome transition-state complex by cryo-electron microscopy

    DEFF Research Database (Denmark)

    Nilsson, Jakob; Sengupta, Jayati; Gursky, Richard

    2008-01-01

    In an attempt to understand ribosome-induced GTP hydrolysis on eEF2, we determined a 12.6-A cryo-electron microscopy reconstruction of the eEF2-bound 80S ribosome in the presence of aluminum tetrafluoride and GDP, with aluminum tetrafluoride mimicking the gamma-phosphate during hydrolysis....... This is the first visualization of a structure representing a transition-state complex on the ribosome. Tight interactions are observed between the factor's G domain and the large ribosomal subunit, as well as between domain IV and an intersubunit bridge. In contrast, some of the domains of eEF2 implicated in small...... and 14. This complex is structurally distinct from the eEF2-bound 80S ribosome complexes previously reported, and analysis of this map sheds light on the GTPase-coupled translocation mechanism....

  4. The phase delay and its complex time: From stationary states up to wave packets

    Energy Technology Data Exchange (ETDEWEB)

    Grossel, Ph., E-mail: philippe.grossel@univ-reims.fr

    2013-03-15

    Complex time is often invoked about tunneling effect where the classical phase delay is completed with a crucial filter effect. Usually the complex times are obtained by considering the flux-flux correlation function, but this can be obtained by a very simple approach using the search of the maximum of the generalized complex phase function, including the amplitude of the wave function. Various aspects of the phase delay are presented in the case of wave packets impinging on simple or resonant quantum barriers. Formal links with the classical mechanics give birth to quasi-trajectories of the quantum particle, totally compatible with the quantum mechanics. - Highlights: Black-Right-Pointing-Pointer The stationary phase method is extended in including the variations of the spectra. Black-Right-Pointing-Pointer The complex phase delay leads to a complex trajectory inside and out-side the barrier. Black-Right-Pointing-Pointer Examples of quasi-trajectories are given in case of different quantum barriers. Black-Right-Pointing-Pointer Phase delays are specified for resonant tunneling or above-barrier wave-packets. Black-Right-Pointing-Pointer The coherence between the quasi-trajectories and quantum mechanics is shown.

  5. Spectroscopic characterization of both aqueous and solid-state diacerhein/hydroxypropyl-β-cyclodextrin inclusion complexes

    Science.gov (United States)

    Petralito, Stefania; Zanardi, Iacopo; Spera, Romina; Memoli, Adriana; Travagli, Valter

    2014-06-01

    Diacerhein, a poorly water soluble antirheumatic prodrug, was spectroscopically characterized to form inclusion complexes with hydroxypropyl-β-cyclodextrin (HPβCD) in both aqueous solution and in solid phase. Complexation with the hydrophilic carriers was used to improve the solubility and dissolution rate of the compound. The kinetics of the prodrug degradation to the active rhein in aqueous buffer solution were also investigated as a function of HPβCD concentration. The solid complexes prepared by different methods such as physical mixture, kneading, co-evaporation method and freeze dried method in 1:1 M ratio, were characterized by DSC and FTIR. The dissolution profiles of solid complexes were determined and compared with diacerhein alone and their physical mixture, in the simulated intestinal fluid at 37 °C. The accurate molecular spectroscopic characterization of diacerhein in the presence of different amounts of aqueous cyclodextrins was essential to determine the correct binding constants for the diacerhein/HPβCD system. The binding constants were also validated by UV spectrometry and HPLC procedure in order to compare the values from the different methods. Higuchi-Connors phase solubility method has proved not suitable when either the free or/and the complexed prodrug degrade in aqueous solution.

  6. Luminescence from the ligand to metal charge transfer state of the neptunyl (V) ion and its complexes in solution

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, Rebecca; Sykes, Daniel; Faulkner, Stephen [University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford (United Kingdom); Natrajan, Louise S; Livens, Francis R [Centre for Radiochemistry Research, School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Taylor, Robin J, E-mail: Stephen.Faulkner@chem.ox.ac.uk [Central Laboratory, National Nuclear Laboratory, Sellafield, Seascale, Cumbria, CA20 1PG (United Kingdom)

    2010-03-15

    The photophysical properties of the neptunyl (V) ion in aqueous solution have been studied using time-resolved luminescence spectroscopy. While any f-f transitions in emission are too weak to detect using available technology, the ligand to metal charge transfer state is emissive in the visible part of the spectrum. Both the aquo ion and its complexes with bidentate ligands exhibit biexponential decay kinetics, which can be rationalised by slow exchange on the timescale of the experiment.

  7. Atomistic modeling of two-dimensional electronic spectra and excited-state dynamics for a Light Harvesting 2 complex.

    Science.gov (United States)

    van der Vegte, C P; Prajapati, J D; Kleinekathöfer, U; Knoester, J; Jansen, T L C

    2015-01-29

    The Light Harvesting 2 (LH2) complex is a vital part of the photosystem of purple bacteria. It is responsible for the absorption of light and transport of the resulting excitations to the reaction center in a highly efficient manner. A general description of the chromophores and the interaction with their local environment is crucial to understand this highly efficient energy transport. Here we include this interaction in an atomistic way using mixed quantum-classical (molecular dynamics) simulations of spectra. In particular, we present the first atomistic simulation of nonlinear optical spectra for LH2 and use it to study the energy transport within the complex. We show that the frequency distributions of the pigments strongly depend on their positions with respect to the protein scaffold and dynamics of their local environment. Furthermore, we show that although the pigments are closely packed the transition frequencies of neighboring pigments are essentially uncorrelated. We present the simulated linear absorption spectra for the LH2 complex and provide a detailed explanation of the states responsible for the observed two-band structure. Finally, we discuss the energy transfer within the complex by analyzing population transfer calculations and 2D spectra for different waiting times. We conclude that the energy transfer from the B800 ring to the B850 ring is mediated by intermediate states that are delocalized over both rings, allowing for a stepwise downhill energy transport.

  8. Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling

    CERN Document Server

    Powell, B J

    2015-01-01

    There is longstanding fundamental interest in 6-fold coordinated $d^6$ ($t_{2g}^6$) transition metal complexes such as [Ru(bpy)$_3$]$^{2+}$ and Ir(ppy)$_3$, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, $T_1$, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of $T_1$ and of the relative radiative rates of the three sublevels in terms of the conservation of time-revers...

  9. Geometries of low spin states of multi-centre transition metal complexes through extended broken symmetry variational Monte Carlo

    Science.gov (United States)

    Barborini, Matteo; Guidoni, Leonardo

    2016-09-01

    The correct description of the ground state electronic and geometrical properties of multi-centre transition metal complexes necessitates of a high-level description of both dynamical and static correlation effects. In di-metallic complexes, the ground state low spin properties can be computed starting from single-determinants High-Spin (HS) and Broken Symmetry (BS) states by reconstructing an approximated low spin potential energy surface through the extended broken symmetry approach, based on the Heisenberg Hamiltonian. In the present work, we first apply this approach within the variational Monte Carlo method to tackle the geometry optimization of a Fe2S2(SH)42- model complex. To describe the HS and BS wavefunctions, we use a fully optimized unrestricted single determinant with a correlated Jastrow factor able to recover a large amount of dynamical correlation. We compared our results with those obtained by density functional theory and other multiconfigurational approaches, discussing the role of the nodal surface on the structural parameters.

  10. Decoding Complex Cognitive States Online by Manifold Regularization in Real-Time fMRI

    DEFF Research Database (Denmark)

    Hansen, Toke Jansen; Hansen, Lars Kai; Madsen, Kristoffer Hougaard

    2011-01-01

    Human decision making is complex and influenced by many factors on multiple time scales, reflected in the numerous brain networks and connectivity patterns involved as revealed by fMRI. We address mislabeling issues in paradigms involving complex cognition, by considering a manifold regularizing...... prior for modeling a sequence of neural events leading to a decision. The method is directly applicable for online learning in the context of real-time fMRI, and our experimental results show that the method can efficiently avoid model degeneracy caused by mislabeling....

  11. Uncertainty Quantification for Complex RF-structures Using the State-space Concatenation Approach

    CERN Document Server

    Heller, Johann; Schmidt, Christian; Van Rienen, Ursula

    2015-01-01

    as well as to employ robust optimizations, a so-called uncertainty quantification (UQ) is applied. For large and complex structures such computations are heavily demanding and cannot be carried out using standard brute-force approaches. In this paper, we propose a combination of established techniques to perform UQ for long and complex structures, where the uncertainty is located only in parts of the structure. As exemplary structure, we investigate the third-harmonic cavity, which is being used at the FLASH accelerator at DESY, assuming an uncertain...

  12. Influence of ligand substitution on excited state structural dynamics in Cu(I) bis-phenanthroline complexes.

    Energy Technology Data Exchange (ETDEWEB)

    Lockard, J. V.; Kabehie, S.; Zink, J. I.; Smolentsev, G.; Soldatov, A.; Chen, L. X. (Chemical Sciences and Engineering Division); (Northwestern Univ.); (Univ. of California at Los Angeles); (Southern Federal Univ.); (Lund Univ.)

    2010-01-01

    This study explores the influences of steric hindrance and excited state solvent ligation on the excited state dynamics of Cu{sup I} diimine complexes. Ultrafast excited state dynamics of Cu(I)bis(3,8-di(ethynyltrityl)-1,10-phenanthroline) [Cu{sup I}(detp){sub 2}]{sup +} are measured using femtosecond transient absorption spectroscopy. The steady state electronic absorption spectra and measured lifetimes are compared to those of Cu(I)bis(1,10-phenanthroline), [Cu{sup I}(phen){sub 2}]{sup +}, and Cu(I)bis(2-9-dimethyl-1,10-phenanthroline), [Cu{sup I}(dmp){sub 2}]{sup +}, model complexes to determine the influence of different substitution patterns of the phenanthroline ligand on the structural dynamics associated with the metal to ligand charge transfer excited states. Similarities between the [Cu{sup I}(detp){sub 2}]{sup +} and [Cu{sup I}(phen){sub 2}]{sup +} excited state lifetimes were observed in both coordinating and noncoordinating solvents and attributed to the lack of steric hindrance from substitution at the 2- and 9-positions. The solution-phase X-ray absorption spectra of [Cu{sup I}(detp){sub 2}]{sup +}, [Cu{sup I}(phen){sub 2}]{sup +}, and [Cu{sup I}(dmp){sub 2}]{sup +} are reported along with finite difference method calculations that are used to determine the degree of ground state dihedral angle distortion in solution and to account for the pre-edge features observed in the XANES region.

  13. Coupled dynamics of node and link states in complex networks: a model for language competition

    Science.gov (United States)

    Carro, Adrián; Toral, Raúl; San Miguel, Maxi

    2016-11-01

    Inspired by language competition processes, we present a model of coupled evolution of node and link states. In particular, we focus on the interplay between the use of a language and the preference or attitude of the speakers towards it, which we model, respectively, as a property of the interactions between speakers (a link state) and as a property of the speakers themselves (a node state). Furthermore, we restrict our attention to the case of two socially equivalent languages and to socially inspired network topologies based on a mechanism of triadic closure. As opposed to most of the previous literature, where language extinction is an inevitable outcome of the dynamics, we find a broad range of possible asymptotic configurations, which we classify as: frozen extinction states, frozen coexistence states, and dynamically trapped coexistence states. Moreover, metastable coexistence states with very long survival times and displaying a non-trivial dynamics are found to be abundant. Interestingly, a system size scaling analysis shows, on the one hand, that the probability of language extinction vanishes exponentially for increasing system sizes and, on the other hand, that the time scale of survival of the non-trivial dynamical metastable states increases linearly with the size of the system. Thus, non-trivial dynamical coexistence is the only possible outcome for large enough systems. Finally, we show how this coexistence is characterized by one of the languages becoming clearly predominant while the other one becomes increasingly confined to ‘ghetto-like’ structures: small groups of bilingual speakers arranged in triangles, with a strong preference for the minority language, and using it for their intra-group interactions while they switch to the predominant language for communications with the rest of the population.

  14. 76 FR 28328 - Fisheries of the Northeastern United States; Northeast Skate Complex Fishery; Framework Adjustment 1

    Science.gov (United States)

    2011-05-17

    ... biological status of the resource. The management measures implemented in Amendment 3 were designed to...) possession limit). Because the only significant alternative considered in this case is the status quo, under... Complex Fishery Management Plan (Skate FMP). Framework Adjustment 1 was developed by the New...

  15. The total quasi-steady-state approximation for complex enzyme reactions

    DEFF Research Database (Denmark)

    Pedersen, Morten Gram; Bersani, A. M.; Bersani, E.

    2008-01-01

    Biochemistry in general and enzyme kinetics in particular have been heavily influenced by the model of biochemical reactions known as Michaelis-Menten kinetics. Assuming that the complex concentration is approximately constant after a short transient phase leads to the usual Michaelis-Menten (MM...

  16. Zirconium-allyl complexes as resting states in zirconocene-catalyzed α-olefin polymerization.

    Science.gov (United States)

    Panchenko, Valentina N; Babushkin, Dmitrii E; Brintzinger, Hans H

    2015-01-01

    UV-vis spectroscopic data indicate that zirconocene cations with Zr-bound allylic chain ends are generally formed during olefin polymerization with zirconocene catalysts. The rates and extent of their formation and of their re-conversion to the initial pre-catalyst cations depend on the types of zirconocene complexes and activators used.

  17. Thermodynamics, structure, and charge state of hydrogen-vacancy complexes in δ-plutonium

    Science.gov (United States)

    Taylor, Christopher D.; Francis, Michael F.; Schwartz, Daniel S.

    2014-06-01

    Hydrogen-vacancy complexes can form in a material due to the exothermic binding of hydrogen atoms to vacancy sites. We explore the structure and electronic properties of hydrogen-vacancy complexes in δ-Pu using a density functional theory supercell approach, with up to eight hydrogen atoms stored in the vacancy site. We find that the hydrogen atoms bind to the inner edge of the vacancy site, preferring pseudo-octahedral configurations that optimize the Pu-H bond length. Hydrogen binding to the vacancy site remains exothermic, with binding energies around -0.4 eV/H atom. A statistical mechanics analysis is derived and applied to reveal the range of hydrogen chemical potentials that would lead to hydrogen-vacancy complex formation. We find that these chemical potentials are higher than those required to form the hydride phase, indicating that hydriding should occur before any appreciable concentration of vacancy-hydrogen complexes is realized. Some remarks are made comparing this theoretical finding to the experimental work on this topic, with suggestions given for future work that may help reconcile some apparent contradictions.

  18. Orthodontic Treatment Need and Complexity among Nigerian Adolescents in Rivers State, Nigeria

    Directory of Open Access Journals (Sweden)

    Elfleda Angelina Aikins

    2011-01-01

    Full Text Available Introduction. The assessment of orthodontic treatment need and complexity are necessary for informed planning of orthodontic services. The aim of this cross-sectional study was to assess these parameters using the Index of Complexity, Outcome, and Need (ICON in a Nigerian adolescent population in a region where orthodontic services are just being established. Methods. Six hundred and twelve randomly selected Nigerian adolescents aged 12 to 18 years were examined using the ICON in their school compounds. Descriptive statistics were employed in the data analysis. Results. Out of a total of 38.1% of the population found to need orthodontic treatment, there were more males and older adolescents. The overall mean ICON score for the population was 39.7±25.3 SD with males having statistically higher mean ICON score. The grades of complexity of the population were 21.6% for very difficult and difficult, 7.5% moderate, and 70.9% mild/easy. Conclusions. Although just over a third of the adolescents were found to have a need for treatment, about a quarter of them were found to have difficult and very difficult complexity grades indicating a need for specialist care. The authors recommend the training of more specialist orthodontists in this region.

  19. Ab initio potential-energy surface and rovibrational states of the HCN-HCl complex

    NARCIS (Netherlands)

    Avoird, A. van der; Pedersen, T.B.; Dhont, G.S.F.; Fernandez, B.; Koch, H.

    2006-01-01

    A four-dimensional intermolecular potential-energy surface has been calculated for the HCN-HCl complex, with the use of the coupled cluster method with single and double excitations and noniterative inclusion of triples. Data for more than 13 000 geometries were represented by an angular expansion i

  20. Loss of BAF (mSWI/SNF Complexes Causes Global Transcriptional and Chromatin State Changes in Forebrain Development

    Directory of Open Access Journals (Sweden)

    Ramanathan Narayanan

    2015-12-01

    Full Text Available BAF (Brg/Brm-associated factors complexes play important roles in development and are linked to chromatin plasticity at selected genomic loci. Nevertheless, a full understanding of their role in development and chromatin remodeling has been hindered by the absence of mutants completely lacking BAF complexes. Here, we report that the loss of BAF155/BAF170 in double-conditional knockout (dcKO mice eliminates all known BAF subunits, resulting in an overall reduction in active chromatin marks (H3K9Ac, a global increase in repressive marks (H3K27me2/3, and downregulation of gene expression. We demonstrate that BAF complexes interact with H3K27 demethylases (JMJD3 and UTX and potentiate their activity. Importantly, BAF complexes are indispensable for forebrain development, including proliferation, differentiation, and cell survival of neural progenitor cells. Our findings reveal a molecular mechanism mediated by BAF complexes that controls the global transcriptional program and chromatin state in development.

  1. Dinuclear Pt(II)-bisphosphonate complexes: a scaffold for multinuclear or different oxidation state platinum drugs.

    Science.gov (United States)

    Piccinonna, Sara; Margiotta, Nicola; Pacifico, Concetta; Lopalco, Antonio; Denora, Nunzio; Fedi, Serena; Corsini, Maddalena; Natile, Giovanni

    2012-08-28

    Geminal bisphosphonates (BPs), used in the clinic for the treatment of hypercalcaemia and skeletal metastases, have been also exploited for promoting the specific accumulation of platinum antitumor drugs in bone tissue. In this work, the platinum dinuclear complex [{Pt(en)}(2)(μ-AHBP-H(2))](+) (1) (the carbon atom bridging the two phosphorous atoms carrying a 2-ammonioethyl and a hydroxyl group, AHBP-H(2)) has been used as scaffold for the synthesis of a Pt(II) trinuclear complex, [{Pt(en)}(3)(μ-AHBP)](+) (2), and a Pt(IV) adamantane-shaped dinuclear complex featuring an oxo-bridge, [{Pt(IV)(en)Cl}(2)(μ-O)(μ-AHBP-H(2))](+) (3) (X-ray structure). Compound 2 undergoes a reversible, pH dependent, rearrangement with a neat switch point around pH = 5.4. Compound 3 undergoes a one-step electrochemical reduction at E(pc) = -0.84 V affording compound 1. Such a potential is far lower than that of glutathione (-0.24 V), nevertheless compound 3 can undergo chemical reduction to 1 by GSH, most probably through a different (inner-sphere) mechanism. In vitro cytotoxicity of the new compounds, tested against murine glioma (C6) and human cervix (HeLa) and hepatoma (HepG2) cell lines, has shown that, while the Pt(IV) dimer 3 is inactive up to a concentration of 50 μM, the two Pt(II) polynuclear compounds 1 and 2 have a cytotoxicity comparable to that of cisplatin with the trinuclear complex 2 generally more active than the dinuclear complex 1.

  2. New AIE-active pyrimidine-based boronfluoride complexes with high solid-state emission and reversible mechanochromism luminescence behavior.

    Science.gov (United States)

    Qi, Fen; Lin, Jianjian; Wang, Xiaoqing; Cui, Peng; Yan, Hui; Gong, Shuwen; Ma, Chunlin; Liu, Zhipeng; Huang, Wei

    2016-04-25

    A new family of pyrimidine-based BF2 complexes () with aggregation-induced emission (AIE) and mechanochromic luminescence properties were developed. These compounds exhibit intense fluorescence in their aggregation/solid-state resulting from their large Stokes shift and AIE. X-ray crystallographic analysis shows that the weak intermolecular interactions by fixing the molecular conformations of are responsible for the intense fluorescence in solid-state. In addition to their pronounced AIE behaviour, also exhibits a reversible chromic response to grinding, and a distinct red-shift of emission is observed. The high solid-state luminescence and grinding-stimuli response properties of these compounds make them potential candidates for smart materials.

  3. Remote preparation of complex spatial states of single photons and verification by two-photon coincidence experiment.

    Science.gov (United States)

    Kang, Yoonshik; Cho, Kiyoung; Noh, Jaewoo; Vitullo, Dashiell L P; Leary, Cody; Raymer, M G

    2010-01-18

    We propose and provide experimental evidence in support of a theory for the remote preparation of a complex spatial state of a single photon. An entangled two-photon source was obtained by spontaneous parametric down-conversion, and a double slit was placed in the path of the signal photon as a scattering object. The signal photon was detected after proper spatial filtering so that the idler photon was prepared in the corresponding single-photon state. By using a two-photon coincidence measurement, we obtained the Radon transform, at several longitudinal distances, of the single-photon Wigner distribution function modified by the double slit. The experimental results are consistent with the idler photon being in a pure state. An inverse Radon transformation can, in principle, be applied to the measured data to reconstruct the modified single-photon Wigner function, which is a complete representation of the amplitude and phase structure of the scattering object.

  4. Generation of bound states of pulses in a soliton laser with complex relaxation of a saturable absorber

    Energy Technology Data Exchange (ETDEWEB)

    Zolotovskii, I O; Korobko, D A; Okhotnikov, O G [Ulyanovsk State University, Ulyanovsk (Russian Federation); Gumenyuk, R V [Optoelectronics Research Center, Tampere University of Technology, Tampere (Finland)

    2015-01-31

    A numerical model of a soliton fibre laser with a semiconductor saturable absorber mirror (SESAM), characterised by the complex dynamics of absorption relaxation, is considered. It is shown that stationary bound states of pulses can be formed in this laser as a result of their interaction via the dispersion-wave field. The stability of stationary bound states of several pulses is analysed. It is shown that an increase in the number of pulses in a stationary bound state leads eventually to its decay and formation of a random bunch. It is found that the bunch stability is caused by the manifestation of nonlinear self-phase modulation, which attracts pulses to the bunch centre. The simulation results are in qualitative agreement with experimental data. (nonlinear optical phenomena)

  5. Automated charge state determination of complex isotope-resolved mass spectra by peak-target Fourier transform.

    Science.gov (United States)

    Chen, Li; Yap, Yee Leng

    2008-01-01

    This study describes a new algorithm for charge state determination of complex isotope-resolved mass spectra. This algorithm is based on peak-target Fourier transform (PTFT) of isotope packets. It is modified from the widely used Fourier transform method because Fourier transform may give ambiguous charge state assignment for low signal-to-noise ratio (S/N) or overlapping isotopic clusters. The PTFT algorithm applies a novel "folding" strategy to enhance peaks that are symmetrically spaced about the targeted peak before applying the FT. The "folding" strategy multiplies each point to the high-m/z side of the targeted peak by its counterpart on the low-m/z side. A Fourier transform of this "folded" spectrum is thus simplified, emphasizing the charge state of the "chosen" ion, whereas ions of other charge states contribute less to the transformed data. An intensity-dependent technique is also proposed for charge state determination from frequency signals. The performance of PTFT is demonstrated using experimental electrospray ionization Fourier transform ion cyclotron resonance mass spectra. The results show that PTFT is robust for charge state determination of low S/N and overlapping isotopic clusters, and also useful for manual verification of potential hidden isotopic clusters that may be missed by the current analysis algorithms, i.e., AID-MS or THRASH.

  6. The lunar-tide cycle viewed by crustacean and mollusc gatherers in the State of Paraíba, Northeast Brazil and their influence in collection attitudes

    Directory of Open Access Journals (Sweden)

    Alves Rômulo RN

    2006-01-01

    Full Text Available Abstract Traditional human communities have a wide knowledge of their environment. Collection of animals in estuarine and coastal areas are directly influenced by tidal cycles. The aim of this study is to evaluate the understanding of the tides associated with the lunar cycle held by people who gather crustaceans and molluscs in the State of Paraiba. The empirical knowledge of 20 crab gatherers and 30 mollusc gatherers was recorded through open interviews and structured questionnaires. The results showed that the gatherers have an accurate comprehension of tidal phenomenon based on their exploitation of natural resources, which perpetuates through generations.

  7. Complex Metal Hydrides for hydrogen storage and solid-state ion conductors

    DEFF Research Database (Denmark)

    Payandeh GharibDoust, SeyedHosein

    and electricity in batteries. However, both hydrogen and electricity must be stored in a very dense way to be useful, e.g. for mobile applications. Complex metal hydrides have high hydrogen density and have been studied during the past twenty years in hydrogen storage systems. Moreover, they have shown high ionic...... conductivities which promote their application as solid electrolytes in batteries. This dissertation presents the synthesis and characterization of a variety of complex metal hydrides and explores their hydrogen storage properties and ionic conductivity. Five halide free rare earth borohydrides RE(BH4)3, (RE...... = La, Ce, Pr, Nd, Er) have been synthesized, which pave the way for studying the polymorphic transition in these compounds, obtaining new bimetallic borohydrides and designing new reactive hydride composites with improved hydrogen storage capacities. Two novel polymorphs of Pr(BH4)3 are identified...

  8. Understanding the Excited State Behavior of Cyclometalated Bis(tridentate)ruthenium(II) Complexes: A Combined Experimental and Theoretical Study.

    Science.gov (United States)

    Kreitner, Christoph; Erdmann, Elisa; Seidel, Wolfram W; Heinze, Katja

    2015-12-07

    The synthesis and characterization of the donor-acceptor substituted cyclometalated ruthenium(II) polypyridine complex isomers [Ru(dpb-NHCOMe)(tpy-COOEt)](PF6) 1(PF6) and [Ru(dpb-COOEt)(tpy-NHCOMe)](PF6) 2(PF6) (dpbH = 1,3-dipyridin-2-ylbenzene, tpy = 2,2';6,2"-terpyridine) with inverted functional group pattern are described. A combination of resonance Raman spectroscopic and computational techniques shows that all intense visible range absorption bands arise from mixed Ru → tpy/Ru → dpb metal-to-ligand charge transfer (MLCT) excitations. 2(PF6) is weakly phosphorescent at room temperature in fluid solution and strongly emissive at 77 K in solid butyronitrile matrix, which is typical for ruthenium(II) polypyridine complexes. Density functional theory calculations revealed that the weak emission of 2(PF6) arises from a (3)MLCT state that is efficiently thermally depopulated via metal-centered ((3)MC) excited states. The activation barrier for the deactivation process was estimated experimentally from variable-temperature emission spectroscopic measurements as 11 kJ mol(-1). In contrast, 1(PF6) is nonemissive at room temperature in fluid solution and at 77 K in solid butyronitrile matrix. Examination of the electronic excited states of 1(PF6) revealed a ligand-to-ligand charge-transfer ((3)LL'CT) as lowest-energy triplet state due to the very strong push-pull effect across the metal center. Because of the orthogonality of the participating ligands, emission from the (3)LL'CT is symmetry-forbidden. Hence, in this type of complex a stronger push-pull effect does not increase the phosphorescence quantum yields but completely quenches the emission.

  9. A Hidden State in Light-Harvesting Complex II Revealed By Multipulse Spectroscopy

    OpenAIRE

    Oort, Bart van; van Grondelle, Rienk; van Stokkum, Ivo H. M.

    2015-01-01

    Light-harvesting complex II (LHCII) is pivotal both for collecting solar radiation for photosynthesis, and for protection against photodamage under high light intensities (via a process called nonphotochemical quenching, NPQ). Aggregation of LHCII is associated with fluorescence quenching, and is used as an in vitro model system of NPQ. However, there is no agreement on the nature of the quencher and on the validity of aggregation as a model system. Here, we use ultrafast multipulse spectrosc...

  10. Complex Adaptive Systems and the Development of Force Structures for the United States Air Force

    Science.gov (United States)

    2014-12-01

    begins with a concise primer on complexity theory, the cutting edge of scientific understanding of organizations and networks, and distills it into a...form of control is seen in the so-called space transport network, a dense collection of trajectories connecting libration points in the solar ...Defense Analyses. 2nd ed. Wash- ington, DC: AIAA, 1994. Reilly, Jeffrey M. “Design: Distilling Clarity for Decisive Action.” Course ma- terials

  11. Mechanism of 1,2-shift through p -complex transition state

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A systematic calculation of the potential curves or surfaces for 1,2-shift has been realized by using MNDO or other models in MOPAC programs. By referring to the previous authors' viewpoints, the 1,2-shift can be divided into two categories. 1,2-electron-deficient shift is that the electronic configuration of the atom which accepts the migrating group is a cation or an electron- deficient atom, and 1,2-anion shift is the one that the accepted atom of the migration group is a negative ion. In terms of the experimental facts and the calculation of the potential surfaces, in electron-deficient shift such as Beckmann or Baeyer-Villiger rearrangement, the migration occurs through a transition complex formed between the p -bond and the cation or electron-deficient migrating group, but in anion shift such as Wittig or Stevens rearrangement, the electron pair in p -orbit excites at first to p * orbit, and then the migration occurs through the new formed complex between the anion migration group and the vacant p orbit. The above mechanisms explain reasonably the intramolecular properties, the configuration retentions of the migration group, and the corresponding migratory aptitudes of the two type 1,2-shifts. The partial and less important free radical reaction of 1,2-anion shift has been explained by the p -complex mechanism too.

  12. Active-state models of ternary GPCR complexes: determinants of selective receptor-G-protein coupling.

    Directory of Open Access Journals (Sweden)

    Ralf C Kling

    Full Text Available Based on the recently described crystal structure of the β2 adrenergic receptor--Gs-protein complex, we report the first molecular-dynamics simulations of ternary GPCR complexes designed to identify the selectivity determinants for receptor-G-protein binding. Long-term molecular dynamics simulations of agonist-bound β2AR-Gαs and D2R-Gαi complexes embedded in a hydrated bilayer environment and computational alanine-scanning mutagenesis identified distinct residues of the N-terminal region of intracellular loop 3 to be crucial for coupling selectivity. Within the G-protein, specific amino acids of the α5-helix, the C-terminus of the Gα-subunit and the regions around αN-β1 and α4-β6 were found to determine receptor recognition. Knowledge of these determinants of receptor-G-protein binding selectivity is essential for designing drugs that target specific receptor/G-protein combinations.

  13. Isotope effects of ground and lowest lying vibrational states of H 3 - x D x O2 - complexes

    Science.gov (United States)

    Ansari, Narjes; Meyer, Hans-Dieter

    2016-02-01

    Isotope effects of the H 3 O2 - anion are investigated. For this, the 24 lowest excited vibrational states of the H 3 - x D x O2 - complexes, with x = 0-3, are computed using two different Hamiltonians, namely, a 7D reduced-dimensionality one with a numerical representation of the kinetic energy operator (KEO) and a 9D full-dimensionality Hamiltonian with an exact analytic KEO. The computations are carried out with the multiconfiguration time-dependent Hartree method. The obtained results show that bridge and terminal H-D exchange cause a variation in energy with or without a rearrangement of states. A clear rearrangement of fundamental modes is observed in bridge H-D exchange of the H 3 O2 - complex, where the frequency of bridge hydrogen stretching (z) is strongly lowered by substitution. The isotope effects show that rotation (ϕ), rocking (u1 + u2), wagging (u1 - u2), and O-O stretch (R) modes are sensitive to terminal H-D exchange, while the bridge-atom bending (x,y) and stretch (z) modes are sensitive to bridge H-D exchange. An influence coefficient, which measures the influence of an excitation of one mode on the various 1D reduced densities, is defined and analyzed in detail. It is shown that the D 3 O2 - complex is more strongly correlated or coupled than the other isotopologues.

  14. Profiles of Quality and Intrusion: The Complex Courtship of State Governments and Higher Education.

    Science.gov (United States)

    Krotseng, Marsha V.

    1990-01-01

    Four works are reviewed that contrast cases of constructive state government/university partnerships with examples of inappropriate involvement, and profile the primary political and governing bodies influencing higher education. The quest for quality without undue intrusion emerges as a recurrent theme. (Author/MSE)

  15. Cellular solid-state NMR on large prokaryotic and eukaryotic membrane protein complexes

    NARCIS (Netherlands)

    Kaplan, M.

    2015-01-01

    Unraveling the structure and dynamics of biomolecules is pivotal to understand their function. Hitherto, structural biology has been dependent on data obtained under in-vitro circumstances thereby neglecting the influence of the natural environment. Here, we developed a solid-state Nuclear Magnetic

  16. Cellular solid-state NMR on large prokaryotic and eukaryotic membrane protein complexes

    NARCIS (Netherlands)

    Kaplan, M.

    2015-01-01

    Unraveling the structure and dynamics of biomolecules is pivotal to understand their function. Hitherto, structural biology has been dependent on data obtained under in-vitro circumstances thereby neglecting the influence of the natural environment. Here, we developed a solid-state Nuclear Magnetic

  17. Binary-state dynamics on complex networks: pair approximation and beyond

    CERN Document Server

    Gleeson, James P

    2012-01-01

    A wide class of binary-state dynamics on networks---including, for example, the voter model, the Bass diffusion model, and threshold models---can be described in terms of transition rates (spin-flip probabilities) that depend on the number of nearest neighbors in each of the two possible states. High-accuracy approximations for the emergent dynamics of such models on uncorrelated, infinite networks are given by recently-developed compartmental models or approximate master equations (AME). Pair approximations (PA) and mean-field theories can be systematically derived from the AME. We show that PA and AME solutions can coincide under certain circumstances, and numerical simulations confirm that PA is highly accurate in these cases. For monotone dynamics (where transitions out of one nodal state are impossible, e.g., SI disease-spread or Bass diffusion), PA and AME give identical results for the fraction of nodes in the infected (active) state for all time, provided the rate of infection depends linearly on the ...

  18. State Regulation of the Regional Agricultural Complex Development: Assessment and Rationalization Issues

    Directory of Open Access Journals (Sweden)

    Natal’ya Viktorovna Mironenko

    2015-11-01

    Full Text Available The article discusses the current state and the main trends in the development of agriculture (on the example of agricultural enterprises in the Vologda Oblast. Nowadays there is a trend of decline in the production of basic agricultural products. The insufficient financing of agricultural enterprises is one of the key reasons for this situation. Internal and external sources of funding can be such tools. As world practice shows, the largest share in the funds, which are at the disposal of agricultural enterprises, accounts for direct budgetary financing. However, in the Russian Federation there is another trend: over the last decades there is noticeable reduction in direct state support of agricultural producers. In addition, in the framework of Russia’s accession to the WTO there will be further decline in such support and simultaneous transfer of financial burden onto agricultural enterprises. Therefore, the government faces an acute problem of planning and forecasting volumes of state support and earnings of agricultural enterprises. In this regard, this work makes a forecast calculation of the amount of public support and the revenue size of agricultural enterprises. To make forecasts the author uses methods of econometric modeling and forecasting (in particular, the method of correlation and regression analysis. The forecasts are presented in 3 scenarios: most realistic, optimistic and pessimistic. The article offers recommendations on determining the actual needs of regional agricultural enterprises in the amount of state support

  19. Manipulating charge transfer excited state relaxation and spin crossover in iron coordination complexes with ligand substitution

    DEFF Research Database (Denmark)

    Zhang, Wenkai; Kjær, Kasper Skov; Alonso-Mori, Roberto

    2017-01-01

    ) Kβ hard X-ray fluorescence spectroscopy with femtosecond time-resolved UV-visible absorption spectroscopy to characterize the electronic excited state dynamics initiated by MLCT excitation of [Fe(CN)4(bpy)]2-. The two experimental techniques are highly complementary; the time-resolved UV...

  20. Alpha-1 Adrenoceptor Hyperresponsiveness in Three Neuropathic Pain States: Complex Regional Pain Syndrome 1, Diabetic Peripheral Neuropathic Pain and Central Pain States Following Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Robert W Teasell

    2004-01-01

    Full Text Available The pathophysiology of the pain associated with complex regional pain syndrome, spinal cord injury and diabetic peripheral neuropathy is not known. The pain of complex regional pain syndrome has often been attributed to abnormal sympathetic nervous system activity based on the presence of vasomotor instability and a frequently reported positive response, albeit a temporary response, to sympathetic blockade. In contrast, the pain below the level of spinal cord injury and diabetic peripheral neuropathy are generally seen as deafferentation phenomena. Each of these pain states has been associated with abnormal sympathetic nervous system function and increased peripheral alpha-1 adrenoceptor activity. This increased responsiveness may be a consequence of alpha-1 adrenoceptor postsynaptic hypersensitivity, or alpha-2 adrenoceptor presynaptic dysfunction with diminished noradrenaline reuptake, increased concentrations of noradrenaline in the synaptic cleft and increased stimulation of otherwise normal alpha-1 adrenoceptors. Plausible mechanisms based on animal research by which alpha-1 adrenoceptor hyperresponsiveness can lead to chronic neuropathic-like pain have been reported. This raises the intriguing possibility that sympathetic nervous system dysfunction may be an important factor in the generation of pain in many neuropathic pain states. Although results to date have been mixed, there may be a greater role for new drugs which target peripheral alpha-2 adrenoceptors (agonists or alpha-1 adrenoceptors (antagonists.

  1. Development of bipolar all-solid-state lithium battery based on quasi-solid-state electrolyte containing tetraglyme-LiTFSA equimolar complex.

    Science.gov (United States)

    Gambe, Yoshiyuki; Sun, Yan; Honma, Itaru

    2015-03-09

    The development of high energy-density lithium-ion secondary batteries as storage batteries in vehicles is attracting increasing attention. In this study, high-voltage bipolar stacked batteries with a quasi-solid-state electrolyte containing a Li-Glyme complex were prepared, and the performance of the device was evaluated. Via the successful production of double-layered and triple-layered high-voltage devices, it was confirmed that these stacked batteries operated properly without any internal short-circuits of a single cell within the package: Their plateau potentials (6.7 and 10.0 V, respectively) were two and three times that (3.4 V) of the single-layered device, respectively. Further, the double-layered device showed a capacity retention of 99% on the 200th cycle at 0.5 C, which is an indication of good cycling properties. These results suggest that bipolar stacked batteries with a quasi-solid-state electrolyte containing a Li-Glyme complex could readily produce a high voltage of 10 V.

  2. Unraveling the complexity of protein backbone dynamics with combined (13)C and (15)N solid-state NMR relaxation measurements.

    Science.gov (United States)

    Lamley, Jonathan M; Lougher, Matthew J; Sass, Hans Juergen; Rogowski, Marco; Grzesiek, Stephan; Lewandowski, Józef R

    2015-09-14

    Typically, protein dynamics involve a complex hierarchy of motions occurring on different time scales between conformations separated by a range of different energy barriers. NMR relaxation can in principle provide a site-specific picture of both the time scales and amplitudes of these motions, but independent relaxation rates sensitive to fluctuations in different time scale ranges are required to obtain a faithful representation of the underlying dynamic complexity. This is especially pertinent for relaxation measurements in the solid state, which report on dynamics in a broader window of time scales by more than 3 orders of magnitudes compared to solution NMR relaxation. To aid in unraveling the intricacies of biomolecular dynamics we introduce (13)C spin-lattice relaxation in the rotating frame (R1ρ) as a probe of backbone nanosecond-microsecond motions in proteins in the solid state. We present measurements of (13)C'R1ρ rates in fully protonated crystalline protein GB1 at 600 and 850 MHz (1)H Larmor frequencies and compare them to (13)C'R1, (15)N R1 and R1ρ measured under the same conditions. The addition of carbon relaxation data to the model free analysis of nitrogen relaxation data leads to greatly improved characterization of time scales of protein backbone motions, minimizing the occurrence of fitting artifacts that may be present when (15)N data is used alone. We also discuss how internal motions characterized by different time scales contribute to (15)N and (13)C relaxation rates in the solid state and solution state, leading to fundamental differences between them, as well as phenomena such as underestimation of picosecond-range motions in the solid state and nanosecond-range motions in solution.

  3. Disentangling the low-energy states of the major light-harvesting complex of plants and their role in photoprotection.

    Science.gov (United States)

    Krüger, Tjaart P J; Ilioaia, Cristian; Johnson, Matthew P; Ruban, Alexander V; van Grondelle, Rienk

    2014-07-01

    The ability to dissipate large fractions of their absorbed light energy as heat is a vital photoprotective function of the peripheral light-harvesting pigment-protein complexes in photosystem II of plants. The major component of this process, known as qE, is characterised by the appearance of low-energy (red-shifted) absorption and fluorescence bands. Although the appearance of these red states has been established, the molecular mechanism, their site and particularly their involvement in qE are strongly debated. Here, room-temperature single-molecule fluorescence spectroscopy was used to study the red emission states of the major plant light-harvesting complex (LHCII) in different environments, in particular conditions mimicking qE. It was found that most states correspond to peak emission at around 700nm and are unrelated to energy dissipative states, though their frequency of occurrence increased under conditions that mimicked qE. Longer-wavelength emission appeared to be directly related to energy dissipative states, in particular emission beyond 770nm. The ensemble average of the red emission bands shares many properties with those obtained from previous bulk in vitro and in vivo studies. We propose the existence of at least three excitation energy dissipating mechanisms in LHCII, each of which is associated with a different spectral signature and whose contribution to qE is determined by environmental control of protein conformational disorder. Emission at 700nm is attributed to a conformational change in the Lut 2 domain, which is facilitated by the conformational change associated with the primary quenching mechanism involving Lut 1.

  4. Homoleptic Ce(III) and Ce(IV) Nitroxide Complexes: Significant Stabilization of the 4+ Oxidation State

    Energy Technology Data Exchange (ETDEWEB)

    Bogart, Justin A.; Lewis, Andrew J.; Medling, Scott A.; Piro, Nicholas A.; Carroll, Patrick J.; Booth, Corwin H.; Schelter, Eric J.

    2014-06-25

    Electrochemical experiments performed on the complex Ce-IV[2-((BuNO)-Bu-t)py](4), where [2-((BuNO)-Bu-t)py](-) = N-tert-butyl-N-2-pyridylnitroxide, indicate a 2.51 V stabilization of the 4+ oxidation state of Ce compared to [(Bu4N)-Bu-n](2)[Ce(NO3)(6)] in acetonitrile and a 2.95 V stabilization compared to the standard potential for the ion under aqueous conditions. Density functional theory calculations suggest that this preference for the higher oxidation state is a result of the tetrakis(nitroxide) ligand framework at the Ce cation, which allows for effective electron donation into, and partial covalent overlap with, vacant 4f orbitals with delta symmetry. The results speak to the behavior of CeO2 and related solid solutions in oxygen uptake and transport applications, in particular an inherent local character of bonding that stabilizes the 4+ oxidation state. The results indicate a cerium(IV) complex that has been stabilized to an unprecedented degree through tuning of its ligand-field environment.

  5. Theoretical investigation of potential energy surface and bound states for the van der Waals complex Ar–BrCl dimer

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Rui [School of Mathematics and Information Science, North China University of Water Resources and Electric Power, Zhengzhou (China); Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan (China); Li, Song, E-mail: lsong@yangtzeu.edu.cn [School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou (China); Chen, Shan-Jun; Chen, Yan [School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou (China); Zheng, Li-Min [Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan (China)

    2015-09-08

    Highlights: • A two-dimensional potential for Ar–BrCl is constructed at the CCSD(T) level. • The PES is characterized by three minima and two saddle points between them. • Bound state calculations were carried out for the complex. - Abstract: The intermolecular potential energy surface (PES) of the ground electronic state for the Ar–BrCl dimer is constructed at the CCSD(T) level with the aug-cc-pVQZ basis set and mid-bond functions. The PES is characterized by three minima and two saddle points. The global minimum corresponding to a collinear Ar–BrCl configuration, which has been observed experimentally, is located at R = 4.10 Å and θ = 2.5° with a well depth of −285.207 cm{sup −1}. A nearly T-shaped structure and an anti-linear Ar–ClBr geometry is also predicted. The bound state calculations are preformed to study intermolecular vibrational modes, rotational levels and average structures for the complex. Our transition frequencies, spectroscopic constants and average structures for all isotopomers of the collinear isomer agree well with experimental data. We have also provided pure rotational transitional frequencies for both nearly T-shaped and anti-linear isomers. These results are significant for further experimental investigations of the Ar–BrCl dimer.

  6. Homoleptic cerium(III) and cerium(IV) nitroxide complexes: significant stabilization of the 4+ oxidation state.

    Science.gov (United States)

    Bogart, Justin A; Lewis, Andrew J; Medling, Scott A; Piro, Nicholas A; Carroll, Patrick J; Booth, Corwin H; Schelter, Eric J

    2013-10-07

    Electrochemical experiments performed on the complex Ce(IV)[2-((t)BuNO)py]4, where [2-((t)BuNO)py](-) = N-tert-butyl-N-2-pyridylnitroxide, indicate a 2.51 V stabilization of the 4+ oxidation state of Ce compared to [(n)Bu4N]2[Ce(NO3)6] in acetonitrile and a 2.95 V stabilization compared to the standard potential for the ion under aqueous conditions. Density functional theory calculations suggest that this preference for the higher oxidation state is a result of the tetrakis(nitroxide) ligand framework at the Ce cation, which allows for effective electron donation into, and partial covalent overlap with, vacant 4f orbitals with δ symmetry. The results speak to the behavior of CeO2 and related solid solutions in oxygen uptake and transport applications, in particular an inherent local character of bonding that stabilizes the 4+ oxidation state. The results indicate a cerium(IV) complex that has been stabilized to an unprecedented degree through tuning of its ligand-field environment.

  7. States of an on-axis two-hydrogenic-impurity complex in concentric double quantum rings

    Energy Technology Data Exchange (ETDEWEB)

    R-Fulla, M., E-mail: marlonfulla@yahoo.com [Escuela de Física, Universidad Nacional de Colombia, A.A. 3840, Medellín (Colombia); Institución Universitaria Pascual Bravo, A.A. 6564, Medellín (Colombia); Marín, J.H.; Suaza, Y.A. [Escuela de Física, Universidad Nacional de Colombia, A.A. 3840, Medellín (Colombia); Duque, C.A. [Grupo de Materia Condensada-U de A, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, calle 70 No. 52-21, Medellín (Colombia); Mora-Ramos, M.E. [Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209, Cuernavaca, Morelos (Mexico)

    2014-06-13

    The energy structure of an on-axis two-donor system (D{sub 2}{sup 0}) confined in GaAs concentric double quantum rings under the presence of magnetic field and hydrostatic pressure was analyzed. Based on structural data for the double quantum ring morphology, a rigorous adiabatic procedure was implemented to separate the electrons' rapid in-plane motions from the slow rotational ones. A one-dimensional equation with an effective angular-dependent potential, which describes the two-electron rotations around the common symmetry axis of quantum rings was obtained. It was shown that D{sub 2}{sup 0} complex characteristic features are strongly dependent on the quantum ring geometrical parameters. Besides, by changing the hydrostatic pressure and magnetic field strengths, it is possible to tune the D{sub 2}{sup 0} energy structure. Our results are comparable to those previously reported for a single and negative ionized donor in a spherical quantum dot after a selective setting of the geometrical parameters of the structure. - Highlights: • We report the eigenenergies of a D{sub 2}{sup 0} complex in concentric double quantum rings. • Our model is versatile enough to analyze the dissociation process D{sub 2}{sup 0}→D{sup 0}+D{sup +}+e{sup −}. • We compare the D{sup 0} eigenenergies in horn toroidal and spherical shaped quantum dots. • We show the effects of hydrostatic pressure and magnetic field on the D{sub 2}{sup 0} spectrum. • The use of hydrostatic pressure provides higher thermal stability to the D{sub 2}{sup 0} complex.

  8. “Designing Danger”: Complex Engineering by Violent Non-State Actors: Introduction to the Special Issue

    Directory of Open Access Journals (Sweden)

    Gary Ackerman

    2016-03-01

    Full Text Available This Special Issue of the Journal of Strategic Security (JSS presents the results of a series of case studies of prior efforts by VNSAs to engage in complex engineering tasks, in the hope of informing strategic assessments of the threat of VNSA exploitation of emerging technologies. One particular concern in international security lies at the nexus of violent non-state actors (VNSAs and sophisticated technologies. When it comes to the assessment of such threats, much of the analysis hinges upon being able to accurately judge the desire and capability of adversaries to successfully carry out complex engineering operations. Yet, the actual process of how and why VNSAs engage in these efforts and the determinants of their success or failure are understudied aspects, at least in terms of systematic comparison across actors, technologies and time periods. This special issue presents the results of a series of case studies of prior efforts by VNSAs to engage in complex engineering tasks, in the hope of informing strategic assessments of the threat of VNSA exploitation of emerging technologies. The introductory article defines a complex engineering effort, summarizes the existing literature on the topic and sets out the methodology and framing questions used in the case studies.

  9. Electrical manipulation of spin states in a single electrostatically gated transition-metal complex

    DEFF Research Database (Denmark)

    Osorio, Edgar A; Moth-Poulsen, Kasper; van der Zant, Herre S J;

    2010-01-01

    We demonstrate an electrically controlled high-spin (S = 5/2) to low-spin (S = 1/2) transition in a three-terminal device incorporating a single Mn(2+) ion coordinated by two terpyridine ligands. By adjusting the gate-voltage we reduce the terpyridine moiety and thereby strengthen the ligand...... a strongly gate-dependent singlet-triplet splitting on the low-spin side. The measured bias-spectroscopy is shown to be consistent with an exact diagonalization of the Mn-complex, and an interpretation of the data is given in terms of a simplified effective model....

  10. A novel frequency tracking method based on complex adaptive linear neural network state vector in power systems

    Energy Technology Data Exchange (ETDEWEB)

    Sadinezhad, I.; Joorabian, M. [Electrical Engineering Department, Shahid Chamran University, Ahvaz 61355 (Iran)

    2009-08-15

    This paper presents the application of a Complex Adaptive Linear Neural Network (CADALINE) in tracking the fundamental power system frequency. In this method, by using stationary-axes Park transformation in addition to producing a complex input measurement, the decaying DC offset is eliminated. As the proposed method uses first-order differentiator to estimate frequency changes, a Hamming filter is used to smoothen the response and cancel high-frequency noises. The most distinguishing features of the proposed method are the reduction in the size of observation state vector required by a simple Adaptive Linear Neural Network (ADALINE) and increase in the accuracy and convergence speed under transient conditions. This paper concludes with the presentation of the representative results obtained in numerical simulation and simulation in PSCAD/EMTDC software as well as in practical study. (author)

  11. A new method for predicting response in complex linear systems. II. [under random or deterministic steady state excitation

    Science.gov (United States)

    Bogdanoff, J. L.; Kayser, K.; Krieger, W.

    1977-01-01

    The paper describes convergence and response studies in the low frequency range of complex systems, particularly with low values of damping of different distributions, and reports on the modification of the relaxation procedure required under these conditions. A new method is presented for response estimation in complex lumped parameter linear systems under random or deterministic steady state excitation. The essence of the method is the use of relaxation procedures with a suitable error function to find the estimated response; natural frequencies and normal modes are not computed. For a 45 degree of freedom system, and two relaxation procedures, convergence studies and frequency response estimates were performed. The low frequency studies are considered in the framework of earlier studies (Kayser and Bogdanoff, 1975) involving the mid to high frequency range.

  12. A Rhodium–Pentane Sigma‐Alkane Complex: Characterization in the Solid State by Experimental and Computational Techniques

    Science.gov (United States)

    Chadwick, F. Mark; Rees, Nicholas H.; Krämer, Tobias; Iannuzzi, Marcella

    2016-01-01

    Abstract The pentane σ‐complex [Rh{Cy2P(CH2CH2)PCy2}(η2:η2‐C5H12)][BArF 4] is synthesized by a solid/gas single‐crystal to single‐crystal transformation by addition of H2 to a precursor 1,3‐pentadiene complex. Characterization by low temperature single‐crystal X‐ray diffraction (150 K) and SSNMR spectroscopy (158 K) reveals coordination through two Rh⋅⋅⋅H−C interactions in the 2,4‐positions of the linear alkane. Periodic DFT calculations and molecular dynamics on the structure in the solid state provide insight into the experimentally observed Rh⋅⋅⋅H−C interaction, the extended environment in the crystal lattice and a temperature‐dependent pentane rearrangement implicated by the SSNMR data. PMID:26880330

  13. A Rhodium-Pentane Sigma-Alkane Complex: Characterization in the Solid State by Experimental and Computational Techniques.

    Science.gov (United States)

    Chadwick, F Mark; Rees, Nicholas H; Weller, Andrew S; Krämer, Tobias; Iannuzzi, Marcella; Macgregor, Stuart A

    2016-03-07

    The pentane σ-complex [Rh{Cy2 P(CH2 CH2 )PCy2 }(η(2) :η(2) -C5 H12 )][BAr(F) 4 ] is synthesized by a solid/gas single-crystal to single-crystal transformation by addition of H2 to a precursor 1,3-pentadiene complex. Characterization by low temperature single-crystal X-ray diffraction (150 K) and SSNMR spectroscopy (158 K) reveals coordination through two Rh⋅⋅⋅H-C interactions in the 2,4-positions of the linear alkane. Periodic DFT calculations and molecular dynamics on the structure in the solid state provide insight into the experimentally observed Rh⋅⋅⋅H-C interaction, the extended environment in the crystal lattice and a temperature-dependent pentane rearrangement implicated by the SSNMR data. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. [Informational cooperation of the complex of software and hardware tools in automatization of state disease control management].

    Science.gov (United States)

    Akimkin, V G; Muzychenko, F V; Malinovskiĭ, A A; Moiseev, A N; Shvedov, D V

    2008-09-01

    Nowadays, taking into account new tasks, that should be resolved by the medical service, could be marked enlargement of informational cooperation at the expense of perspective program-technical solutions, put in the complex of program-technical means of automatization of administration of state disease control CPTMADC during it's creating. It's planed to elaborate an additional programmatic module for the purpose of using in CPTMADC the methodology of valuation of risk for resolving of tasks of socially-hygienic monitoring. Before it's elaborating, there was examined a capacity to conversion of patterns of weekly reports about the sanitarian condition of objects and it's following using for informational transporting using electronic means of connection of the complex CPTMADC by the way of including in patterns the data about the staff under the influence of adverse factor, and following rangering the objects by the level of risk for staff.

  15. A complex control system based on the fuzzy PID control and state predictor feedback control

    Institute of Scientific and Technical Information of China (English)

    Zhengxi Li; Jie Liu; Dehui Sun; Rentao Zhao

    2004-01-01

    A multi-mode adaptive controller was proposed. The controller features in the combination of Bang-bang and Fuzzy PID controls with state predictor. When large error exists, the controller operates in Bang-bang mode, otherwise it works as a fuzzy PID controller. For only few parameters to be adjusted, the real time controlled system achieveed good stability and fast response. Furthermore, the introduction of state observer was also discussed to extend the capability of the proposed controller to the plant with time-delay factors. The classical PID controller and the multi-mode controller were applied to the same second-order system successively. By comparison of the simulation results, the effectiveness of the controller were shown. At last, on electric-wire production line, this approach was practiced to control electric-wire diameter with an additive random disturbance signal. The test result further proved the effectiveness of the multi-mode controller.

  16. The Complexity of the Consistency and N-representability Problems for Quantum States

    CERN Document Server

    Liu, Yi-Kai

    2007-01-01

    QMA (Quantum Merlin-Arthur) is the quantum analogue of the class NP. There are a few QMA-complete problems, most notably the ``Local Hamiltonian'' problem introduced by Kitaev. In this dissertation we show some new QMA-complete problems. The first one is ``Consistency of Local Density Matrices'': given several density matrices describing different (constant-size) subsets of an n-qubit system, decide whether these are consistent with a single global state. This problem was first suggested by Aharonov. We show that it is QMA-complete, via an oracle reduction from Local Hamiltonian. This uses algorithms for convex optimization with a membership oracle, due to Yudin and Nemirovskii. Next we show that two problems from quantum chemistry, ``Fermionic Local Hamiltonian'' and ``N-representability,'' are QMA-complete. These problems arise in calculating the ground state energies of molecular systems. N-representability is a key component in recently developed numerical methods using the contracted Schrodinger equation...

  17. Mechanism of 1,2-shift through π-complex transition state

    Institute of Scientific and Technical Information of China (English)

    戴乾圜; 周志刚; 张大平

    2000-01-01

    A systematic calculation of the potential curves or surfaces for 1,2-shift has been realized by using MNDO or other models in MOPAC programs. By referring to the previous authors’ viewpoints, the 1,2-shift can be divided into two categories. 1,2-electron-deficient shift is that the electronic configuration of the atom which accepts the migrating group is a cation or an electron-deficient atom, and 1,2-anion shift is the one that the accepted atom of the migration group is a negative ion. In terms of the experimental facts and the calculation of the potential surfaces, in electron-deficient shift such as Beckmann or Baeyer-Villiger rearrangement, the migration occurs through a transition complex formed between the 7i-bond and the cation or electron-deficient migrating group, but in anion shift such as Wittig or Stevens rearrangement, the electron pair in it-orbit excites at first to π* orbit, and then the migration occurs through the new formed complex between the anion migration group and the vacant rc

  18. Diverse Molecular Genotypes of Mycobacterium tuberculosis Complex Isolates Circulating in the Free State, South Africa

    Directory of Open Access Journals (Sweden)

    Anneke Van der Spoel van Dijk

    2016-01-01

    Full Text Available Tuberculosis is a serious public health concern especially in Africa and Asia. Studies describing strain diversity are lacking in the Free State region of South Africa. The aim of the study was to describe the diversity of Mycobacterium tuberculosis (M. tuberculosis strain families in the Free State province of South Africa. A total of 86 M. tuberculosis isolates were genotyped using spoligotyping. A 12-locus mycobacterial interspersed repetitive units-variable-number tandem repeats (MIRU-VNTRs typing was used to further characterize the resulting spoligotyping clusters. SITVITWEB identified 49 different patterns with allocation to six lineages including Latin-American-Mediterranean (LAM (18 isolates, T (14 isolates, Beijing (five isolates, S (six isolates, Haarlem (one isolate, and X (five isolates, while 37 (43.0% orphans were identified. Eight clusters included 37 isolates with identical spoligotypes (2 to 13/cluster. MIRU-VNTR typing further differentiated three spoligotyping clusters: SIT1/Beijing/MIT17, SIT33/LAM3/MIT213, and confirmed one SIT34/S/MIT311. In addition, SpolDB3/RIM assignment of the orphan strains resulted in a further 10 LAM and 13 T families. In total, LAM (28 isolates and T (27 isolates cause 63% of the individual cases of MTB in our study. The Free State has a highly diverse TB population with LAM being predominant. Further studies with inclusion of multidrug-resistant strains with larger sample size are warranted.

  19. A complex state transition from the black hole candidate Swift J1753.5-0127

    CERN Document Server

    Soleri, P; Motta, S; Belloni, T; Casella, P; Méndez, M; Altamirano, D; Linares, M; Wijnands, R; Fender, R; van der Klis, M

    2012-01-01

    We present our monitoring campaign of the outburst of the black-hole candidate Swift J1753.5-0127, observed with the Rossi X-ray Timing Explorer and the Swift satellites. After ~4.5 years since its discovery, the source had a transition to the hard intermediate state. We performed spectral and timing studies of the transition showing that, unlike the majority of the transient black holes, the system did not go to the soft states but it returned to the hard state after a few months. During this transition Swift J1753.5-0127 features properties which are similar to those displayed by the black hole Cygnus X-1. We compared Swift J1753.5-0127 to one dynamically confirmed black hole and two neutron stars showing that its power spectra are in agreement with the binary hosting a black hole. We also suggest that the prolonged period at low flux that followed the initial flare is reminiscent of that observed in other X-ray binaries, as well as in cataclysmic variables.

  20. Single molecule magnet behavior of a pentanuclear Mn-based metallacrown complex: solid state and solution magnetic studies.

    Science.gov (United States)

    Zaleski, Curtis M; Tricard, Simon; Depperman, Ezra C; Wernsdorfer, Wolfgang; Mallah, Talal; Kirk, Martin L; Pecoraro, Vincent L

    2011-11-21

    The magnetic behavior of the pentanuclear complex of formula Mn(II)(O(2)CCH(3))(2)[12-MC(Mn(III)(N)shi)-4](DMF)(6), 1, was investigated using magnetization and magnetic susceptibility measurements both in the solid state and in solution. Complex 1 has a nearly planar structure, made of a central Mn(II) ion surrounded by four peripheral Mn(III) ions. Solid state variable-field dc magnetic susceptibility experiments demonstrate that 1 possesses a low value for the total spin in the ground state; fitting appropriate expressions to the data results in antiferromangetic coupling both between the peripheral Mn(III) ions (J = -6.3 cm(-1)) and between the central Mn(II) ion and the Mn(III) ones (J' = -4.2 cm(-1)). In order to obtain a reasonable fit, a relatively large single ion magnetic anisotropy (D) value of 1 cm(-1) was necessary for the central Mn(II) ion. The single crystal magnetization measurements using a microsquid array display a very slight opening of the hysteresis loop but only at a very low temperature (0.04 K), which is in line with the ac susceptibility data where a slow relaxation of the magnetization occurs just around 2 K. In frozen solution, complex 1 displays a frequency dependent ac magnetic susceptibility signal with an energy barrier to magnetization reorientation (E) and relaxation time at an infinite temperature (τ(o)) of 14.7 cm(-1) and 1.4 × 10(-7) s, respectively, demonstrating the single molecule magnetic behavior in solution.

  1. Activation energies as the validity criterion of a model for complex reactions that can be in oscillatory states

    Directory of Open Access Journals (Sweden)

    Anić S.

    2007-01-01

    Full Text Available Modeling of any complex reaction system is a difficult task. If the system under examination can be in various oscillatory dynamic states, the apparent activation energies corresponding to different pathways may be of crucial importance for this purpose. In that case the activation energies can be determined by means of the main characteristics of an oscillatory process such as pre-oscillatory period, duration of the oscillatory period, the period from the beginning of the process to the end of the last oscillation, number of oscillations and others. All is illustrated on the Bray-Liebhafsky oscillatory reaction.

  2. User's manual for EVITS: a steady state fluids code for complex two-dimensional geometries

    Energy Technology Data Exchange (ETDEWEB)

    Domanus, H.M.

    1976-07-01

    A 2-D computer code, EVITS, has been developed for estimating steady state, incompressible, isothermal flow fields in complex geometries. A vorticity-stream function formulation is used along with a model to resolve viscous effects at solid boundaries. Sufficient geometry and boundary type options are included within the code so that a large number of flow situations can be specified without modifying the program. All instructions to the code are via an input dataset. Detailed instructions for preparing the user oriented input, along with examples, are included in this users' manual.

  3. Electrical manipulation of spin states in a single electrostatically gated transition-metal complex

    DEFF Research Database (Denmark)

    Osorio, Edgar A; Moth-Poulsen, Kasper; van der Zant, Herre S J

    2010-01-01

    We demonstrate an electrically controlled high-spin (S = 5/2) to low-spin (S = 1/2) transition in a three-terminal device incorporating a single Mn(2+) ion coordinated by two terpyridine ligands. By adjusting the gate-voltage we reduce the terpyridine moiety and thereby strengthen the ligand......-field on the Mn-atom. Adding a single electron thus stabilizes the low-spin configuration and the corresponding sequential tunnelling current is suppressed by spin-blockade. From low-temperature inelastic cotunneling spectroscopy, we infer the magnetic excitation spectrum of the molecule and uncover also...... a strongly gate-dependent singlet-triplet splitting on the low-spin side. The measured bias-spectroscopy is shown to be consistent with an exact diagonalization of the Mn-complex, and an interpretation of the data is given in terms of a simplified effective model....

  4. Current state and development trends of the agroindustrial complex and rural territories of Perm Region

    Directory of Open Access Journals (Sweden)

    Gennadiy Vladimirovich Klimenkov

    2011-12-01

    Full Text Available Analysis of regional agricultural sector status and rural areas of Perm in 1990-2011 years indicates a systemic crisis of agriculture in Perm region, which is largely determined by the fact that Perm region has no strategy or strategic plan and program for sustainable agricultural sector and rural areas of Perm region development, there is no scheme of territorial development and master plans of territorial development with the development of agro-industrial complex of Perm region. In these circumstances, there is a steady downward trend in production, weakening and bankruptcy of enterprises, social impoverishment of rural areas, appearance of many of irreversible processes (sale and neglect of agricultural land, demographic problems associated with low living standards, population migration, policy optimization in the areas of education and health, union of territories, policy of depopulation of territories etc.. This paper presents main recommendations for improving the situation in agriculture of Perm region.

  5. Application of the cubic-plus-association (CPA) equation of state to complex mixtures with aromatic hydrocarbons

    DEFF Research Database (Denmark)

    Folas, Georgios; Kontogeorgis, Georgios; Michelsen, Michael Locht;

    2006-01-01

    The cubic-plus-association (CPA) equation of state is applied to phase equilibria of mixtures containing alcohols, glycols, water, and aromatic or olefinic hydrocarbons. Previously, CPA has been successfully used for mixtures containing various associating compounds (alcohols, glycols, amines......, organic acids, and water) and aliphatic hydrocarbons. We show in this work that the model can be satisfactorily extended to complex vapor-liquid-liquid equilibria with aromatic or olefinic hydrocarbons. The solvation between aromatics/olefinics and polar compounds is accounted for. This is particularly...... of the model (the Soave-Redlich-Kwong (SRK) equation of state) can be obtained from mixtures with aliphatic hydrocarbons. For mixtures of glycols with aromatic hydrocarbons, two parameters have been fitted to experimental data, one in the physical (SRK) part and one in the association part of the model...

  6. Ultrafast Spin-State Dynamics in Transition-Metal Complexes Triggered by Soft-X-Ray Light

    Science.gov (United States)

    Wang, Huihui; Bokarev, Sergey I.; Aziz, Saadullah G.; Kühn, Oliver

    2017-01-01

    Recent advances in attosecond physics provide access to the correlated motion of valence and core electrons on their intrinsic timescales. For valence excitations, processes related to the electron spin are usually driven by nuclear motion. For core-excited states, where the core hole has a nonzero angular momentum, spin-orbit coupling is strong enough to drive spin flips on a much shorter time scale. Here, unprecedented short spin crossover is demonstrated for L -edge (2 p →3 d ) excited states of a prototypical Fe(II) complex. It occurs on a time scale, which is faster than the core-hole lifetime of about 4 fs and can be manipulated by the excitation conditions. A detailed analysis of such phenomena will help to gain a fundamental understanding of spin-crossover processes and establish the basis for their control by light.

  7. Modeling of dielectric properties of complex fluids with an equation of state

    DEFF Research Database (Denmark)

    Maribo-Mogensen, Bjørn; Kontogeorgis, Georgios M.; Thomsen, Kaj

    2013-01-01

    permittivity) can be modeled simultaneously with thermodynamic properties. The static permittivity is calculated from an extension of the framework developed by Onsager, Kirkwood, and Fröhlich to associating mixtures. The thermodynamic properties are calculated from the cubic-plus-association (CPA) equation...... of state that includes the Wertheim association model as formulated in the statistical associating fluid theory (SAFT) to account for hydrogen bonding molecules. We show that, by using a simple description of the geometry of the association, we may calculate the Kirkwood g-factor as a function...

  8. Processes of globalization, economic policy and the role of state in raw materials and energy complex

    Directory of Open Access Journals (Sweden)

    Vladimír Vodzinský

    2009-09-01

    Full Text Available Authors dedicate this article to impacts of constrains in paradigm of potentials forming our society.As entire societies are assembled in certain pattern, this article is dedicated to reasoning why economical growth builton influence and a use of knowledge of the reasons would accelerate consumer orientation of reproduction cycle on the levelof ownership.Both of these, causes and reasons, result in aggravation of social order and ecological crises.End products of globalization and concomitant state economic policies do not lead to crisis solution nor do they lead to effectivedisappearance of their consequences.

  9. Observation of a Novel Low-Lying Excited State in Zinc Complexes.

    Science.gov (United States)

    1985-01-22

    Truesdell and G. A. Crosby * Prepared for Publication In The Journal of the American Chemical Society Washington State University Chemical Physics Program...spin signature has not yet been determined. 14 J J- I.F. ...r at.ion/___.. Ielt I, ty Codes Av-*l and/er This work supported in part by the Office of...REFERENCES (I) -Bray, R. G.; Ferguson, J.; Hawkins, C. J. Aust. J. Chem. 1969, 22, 2091. (2) Highland, R. G.; Crosby, G.A. Manuscript In preparation . (3

  10. Soil Organic Matter in Its Native State: Unravelling the Most Complex Biomaterial on Earth.

    Science.gov (United States)

    Masoom, Hussain; Courtier-Murias, Denis; Farooq, Hashim; Soong, Ronald; Kelleher, Brian P; Zhang, Chao; Maas, Werner E; Fey, Michael; Kumar, Rajeev; Monette, Martine; Stronks, Henry J; Simpson, Myrna J; Simpson, André J

    2016-02-16

    Since the isolation of soil organic matter in 1786, tens of thousands of publications have searched for its structure. Nuclear magnetic resonance (NMR) spectroscopy has played a critical role in defining soil organic matter but traditional approaches remove key information such as the distribution of components at the soil-water interface and conformational information. Here a novel form of NMR with capabilities to study all physical phases termed Comprehensive Multiphase NMR, is applied to analyze soil in its natural swollen-state. The key structural components in soil organic matter are identified to be largely composed of macromolecular inputs from degrading biomass. Polar lipid heads and carbohydrates dominate the soil-water interface while lignin and microbes are arranged in a more hydrophobic interior. Lignin domains cannot be penetrated by aqueous solvents even at extreme pH indicating they are the most hydrophobic environment in soil and are ideal for sequestering hydrophobic contaminants. Here, for the first time, a complete range of physical states of a whole soil can be studied. This provides a more detailed understanding of soil organic matter at the molecular level itself key to develop the most efficient soil remediation and agricultural techniques, and better predict carbon sequestration and climate change.

  11. Hydrologic consistency as a basis for assessing complexity of monthly water balance models for the continental United States

    Science.gov (United States)

    Martinez, Guillermo F.; Gupta, Hoshin V.

    2011-12-01

    Methods to select parsimonious and hydrologically consistent model structures are useful for evaluating dominance of hydrologic processes and representativeness of data. While information criteria (appropriately constrained to obey underlying statistical assumptions) can provide a basis for evaluating appropriate model complexity, it is not sufficient to rely upon the principle of maximum likelihood (ML) alone. We suggest that one must also call upon a "principle of hydrologic consistency," meaning that selected ML structures and parameter estimates must be constrained (as well as possible) to reproduce desired hydrological characteristics of the processes under investigation. This argument is demonstrated in the context of evaluating the suitability of candidate model structures for lumped water balance modeling across the continental United States, using data from 307 snow-free catchments. The models are constrained to satisfy several tests of hydrologic consistency, a flow space transformation is used to ensure better consistency with underlying statistical assumptions, and information criteria are used to evaluate model complexity relative to the data. The results clearly demonstrate that the principle of consistency provides a sensible basis for guiding selection of model structures and indicate strong spatial persistence of certain model structures across the continental United States. Further work to untangle reasons for model structure predominance can help to relate conceptual model structures to physical characteristics of the catchments, facilitating the task of prediction in ungaged basins.

  12. Direct measurement of the Mn(II) hydration state in metal complexes and metalloproteins through 17O NMR line widths.

    Science.gov (United States)

    Gale, Eric M; Zhu, Jiang; Caravan, Peter

    2013-12-11

    Here we describe a simple method to estimate the inner-sphere hydration state of the Mn(II) ion in coordination complexes and metalloproteins. The line width of bulk H2(17)O is measured in the presence and absence of Mn(II) as a function of temperature, and transverse (17)O relaxivities are calculated. It is demonstrated that the maximum (17)O relaxivity is directly proportional to the number of inner-sphere water ligands (q). Using a combination of literature data and experimental data for 12 Mn(II) complexes, we show that this method provides accurate estimates of q with an uncertainty of ±0.2 water molecules. The method can be implemented on commercial NMR spectrometers working at fields of 7 T and higher. The hydration number can be obtained for micromolar Mn(II) concentrations. We show that the technique can be extended to metalloproteins or complex:protein interactions. For example, Mn(II) binds to the multimetal binding site A on human serum albumin with two inner-sphere water ligands that undergo rapid exchange (1.06 × 10(8) s(-1) at 37 °C). The possibility of extending this technique to other metal ions such as Gd(III) is discussed.

  13. Time-dependent density functional theory study on the electronic excited-state geometric structure, infrared spectra, and hydrogen bonding of a doubly hydrogen-bonded complex.

    Science.gov (United States)

    Liu, Yufang; Ding, Junxia; Liu, Ruiqiong; Shi, Deheng; Sun, Jinfeng

    2009-12-01

    The geometric structures and infrared (IR) spectra in the electronically excited state of a novel doubly hydrogen-bonded complex formed by fluorenone and alcohols, which has been observed by IR spectra in experimental study, are investigated by the time-dependent density functional theory (TDDFT) method. The geometric structures and IR spectra in both ground state and the S(1) state of this doubly hydrogen-bonded FN-2MeOH complex are calculated using the DFT and TDDFT methods, respectively. Two intermolecular hydrogen bonds are formed between FN and methanol molecules in the doubly hydrogen-bonded FN-2MeOH complex. Moreover, the formation of the second intermolecular hydrogen bond can make the first intermolecular hydrogen bond become slightly weak. Furthermore, it is confirmed that the spectral shoulder at around 1700 cm(-1) observed in the IR spectra should be assigned as the doubly hydrogen-bonded FN-2MeOH complex from our calculated results. The electronic excited-state hydrogen bonding dynamics is also studied by monitoring some vibraitonal modes related to the formation of hydrogen bonds in different electronic states. As a result, both the two intermolecular hydrogen bonds are significantly strengthened in the S(1) state of the doubly hydrogen-bonded FN-2MeOH complex. The hydrogen bond strengthening in the electronically excited state is similar to the previous study on the singly hydrogen-bonded FN-MeOH complex and play important role on the photophysics of fluorenone in solutions.

  14. Sandy Point, Green Cay and Buck Island National Wildlife Refuges: United States Virgin Islands, Caribbean Islands National Wildlife Refuge Complex: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on United States Virgin Islands, Caribbean Islands NWR Complex for the next 15 years. This...

  15. Complex step-based low-rank extended Kalman filtering for state-parameter estimation in subsurface transport models

    KAUST Repository

    El Gharamti, Mohamad

    2014-02-01

    The accuracy of groundwater flow and transport model predictions highly depends on our knowledge of subsurface physical parameters. Assimilation of contaminant concentration data from shallow dug wells could help improving model behavior, eventually resulting in better forecasts. In this paper, we propose a joint state-parameter estimation scheme which efficiently integrates a low-rank extended Kalman filtering technique, namely the Singular Evolutive Extended Kalman (SEEK) filter, with the prominent complex-step method (CSM). The SEEK filter avoids the prohibitive computational burden of the Extended Kalman filter by updating the forecast along the directions of error growth only, called filter correction directions. CSM is used within the SEEK filter to efficiently compute model derivatives with respect to the state and parameters along the filter correction directions. CSM is derived using complex Taylor expansion and is second order accurate. It is proven to guarantee accurate gradient computations with zero numerical round-off errors, but requires complexifying the numerical code. We perform twin-experiments to test the performance of the CSM-based SEEK for estimating the state and parameters of a subsurface contaminant transport model. We compare the efficiency and the accuracy of the proposed scheme with two standard finite difference-based SEEK filters as well as with the ensemble Kalman filter (EnKF). Assimilation results suggest that the use of the CSM in the context of the SEEK filter may provide up to 80% more accurate solutions when compared to standard finite difference schemes and is competitive with the EnKF, even providing more accurate results in certain situations. We analyze the results based on two different observation strategies. We also discuss the complexification of the numerical code and show that this could be efficiently implemented in the context of subsurface flow models. © 2013 Elsevier B.V.

  16. Dynamic translocation of ligand-complexed DNA through solid-state nanopores with optical tweezers.

    Science.gov (United States)

    Sischka, Andy; Spiering, Andre; Khaksar, Maryam; Laxa, Miriam; König, Janine; Dietz, Karl-Josef; Anselmetti, Dario

    2010-11-17

    We investigated the threading and controlled translocation of individual lambda-DNA (λ-DNA) molecules through solid-state nanopores with piconewton force sensitivity, millisecond time resolution and picoampere ionic current sensitivity with a set-up combining quantitative 3D optical tweezers (OT) with electrophysiology. With our virtually interference-free OT set-up the binding of RecA and single peroxiredoxin protein molecules to λ-DNA was quantitatively investigated during dynamic translocation experiments where effective forces and respective ionic currents of the threaded DNA molecule through the nanopore were measured during inward and outward sliding. Membrane voltage-dependent experiments of reversible single protein/DNA translocation scans yield hysteresis-free, asymmetric single-molecule fingerprints in the measured force and conductance signals that can be attributed to the interplay of optical trap and electrostatic nanopore potentials. These experiments allow an exact localization of the bound protein along the DNA strand and open fascinating applications for label-free detection of DNA-binding ligands, where structural and positional binding phenomena can be investigated at a single-molecule level.

  17. A new method to study complex materials in solid state chemistry: application to chalcogenide materials

    Science.gov (United States)

    Lippens, P. E.; Olivier-Fourcade, J.; Jumas, J. C.

    1998-08-01

    We show that a combined application of Mössbauer spectroscopy and other experimental tools such as X-ray photoelectron spectroscopy, X-ray absorption spectroscopy and nuclear magnetic resonance provides a coherent picture of the local electronic structure in chalcogenide materials. In order to develop this idea we propose an analysis of the Sn, Sb and Te local electronic structures for three different systems of materials. The first example concerns the In Sn S system. We show that Li insertion in In16Sn4S32 leads to changes of the Sn oxidation states from Sn(IV) to Sn(II). The second example concerns materials of the Tl Sb S system. We show that variations of the 121Sb Mössbauer isomer shift and surface of the first peak of the X-ray absorption spectra at the Sb LIII edge can be linearly correlated because of the main influence of the Sb 5s electrons. This is explained by changes in the local environment of the Sb atoms. The last example concerns the crystalline phases of the Tl Sn Te system. The formal oxidation numbers of the Te atoms are determined from 125Te Mössbauer spectroscopy and X-ray photoelectron spectroscopy. They are related to the different types of bonds involving the Te atoms in the Tl Sn Te compounds.

  18. State stiffness parameters of the vascular wall in hypertensive patients complex therapy cytoprotector and sartans

    Directory of Open Access Journals (Sweden)

    V. P. Mikhin

    2015-01-01

    Full Text Available A randomized study of the state of stiffness parameters arteries wall (CAVI — cardio-ankle vascular index, AI (augmentation index PEP (duration of the voltage of the left ventricle using «VaSera-1000» («Fukuda Denshi», Japan in primary hypertension patients (80 not treated with systemic antihypertensive therapy. The effect of long-term (3 months was be marketed. Losartan combined with Mexicor 300mg/day or mildronate 1000 mg/day for the specified parameters. It sets the initial reduction the properties of the arterial wall in patients with hypertension, in contrast to healthy individuals. Mexicor or mildronat accompanied by improvement east-cal properties of the arterial wall, reducing CAVI and AI in 3 months on 9.4% and 8.9%, 14.9% and 15.4%, respectively. In the control group-term change CAVI and AI no. Mexicor led to a more pronounced increase in PEP, than mildronate, respectively, on 23.7% and 18.9%. Losartan monotherapy results in a less pronounced decrease in the stiffness of the vessel wall.

  19. Control system of mobile radiographic complex to study equations of state of substances

    Science.gov (United States)

    Belov, O. V.; Valekzhanin, R. V.; Kustov, D. V.; Shamro, O. A.; Sharov, T. V.

    2017-05-01

    A source of x-ray radiation is one of the tools to study equations of state of substances in dynamics. The mobile radiographic bench based on BIM-1500 [1] was developed in RFNC-VNIIEF to increase output parameters of the x-ray radiation source. From automated control system side, BIM-1500 is a set of six high-voltage generators based on the capacitive energy storage, technological equipment, and elements of a blocking system. This paper considers automated control system of the mobile radiographic bench MCA BIM 1500. It consists of six high-voltage generator control circuits, synchronization subsystem, and block subsystem. The object of control has some peculiarities: high level of electromagnetic noise, remoteness of the control panel from the object of control. In connection with this, the coupling devices are arranged closer to the object of control and performed in the form of a set of galvanically insulated control units, which are combined into a net. The operator runs MCA BIM using the operator’s screens on PC or by means of manual control on the equipment in the mode of debugging. The control software provides performance of the experiment in automatic regime in accordance with preset settings. The operator can stop the experiment at the stage of charging the capacitive storage.

  20. The valence state of technetium-99 in its complexes with bleomycin, 1-hydroxy-ethylidene-1,1-diphosphonate and human serum albumin

    NARCIS (Netherlands)

    Korteland, J.; Dekker, B.G.; Ligny, C.L. de

    1980-01-01

    The valence state of technetium-99 in its complexes with bleomycin, 1-hydroxy-ethylidene-1,1-diphosphonate and human serum albumin was determined by titration of 99TcO4− with Sn(II) in the presence of these complexing agents. Both direct titration, and addition of an excess of Sn(II) and back-titrat

  1. Sulfato-bridged ECE-pincer palladium(II) complexes: structures in the solid-state and in solution, and catalytic properties

    NARCIS (Netherlands)

    Kruithof, C.A.; Berger, A.; Dijkstra, H.P.; Soulimani, F.; Visser, T.; Lutz, M.; Spek, A.L.; Klein Gebbink, R.J.M.; van Koten, G.

    2009-01-01

    ECE-pincer sulfato palladium complexes (pincer = [C(6)H(3)(CH(2)E)(2)-2,6](-); E = SPh (), SMe (), S(t)Bu (), NMe(2) ()) were synthesized and characterized. In the solid-state (X-ray determinations) and exist as neutral ECE-pincer palladium sulfato complexes with a mu(2)-O,O' bridging sulfato ligand

  2. The valence state of technetium-99 in its complexes with bleomycin, 1-hydroxy-ethylidene-1,1-diphosphonate and human serum albumin

    NARCIS (Netherlands)

    Korteland, J.; Dekker, B.G.; Ligny, C.L. de

    1980-01-01

    The valence state of technetium-99 in its complexes with bleomycin, 1-hydroxy-ethylidene-1,1-diphosphonate and human serum albumin was determined by titration of 99TcO4− with Sn(II) in the presence of these complexing agents. Both direct titration, and addition of an excess of Sn(II) and back-titrat

  3. Impact of Substituents on Excited-State and Photosensitizing Properties in Cationic Iridium(III) Complexes with Ligands of Coumarin 6.

    Science.gov (United States)

    Takizawa, Shin-Ya; Ikuta, Naoya; Zeng, Fanyang; Komaru, Shohei; Sebata, Shinogu; Murata, Shigeru

    2016-09-01

    A series of bis-cyclometalated cationic iridium (Ir) complexes were synthesized employing two coumarin 6 ligands and a 2,2'-bipyridine (bpy) with various substituents as new sensitizers, realizing both features of strong visible-light absorption and long-lived excited state. Complexes 2-4, with electron-donating methyl and methoxy groups, absorbed visible light strongly (ε: 126 000-132 000 M(-1) cm(-1)) and exhibited room-temperature phosphorescence with remarkably long lifetimes (21-23 μs) in dichloromethane. In contrast, the excited state of prototype complex 1 without any substituents was short-lived, particularly in highly polar acetonitrile. Phosphorescence of complex 5 with the strong electron-withdrawing CF3 groups was too weak to be detected at room temperature even in less polar dichloromethane. The triplet energies of their coumarin ligand-centered ((3)LC) phosphorescent states were almost invariable, demonstrating that selective tuning of the excited-state lifetime is possible through this "simple chemical modification of the bpy ligand" (we name it the "SCMB" method). The spectroscopic and computational investigations in this study suggest that a potential source of the nonradiative deactivation is a triplet ligand-to-ligand charge-transfer state ((3)LLCT state, coumarin 6 → bpy) and lead us to conclude that the energy level of this dark (3)LLCT state, as well as its thermal population, is largely dependent on the substituents and solvent polarity. In addition, the significant difference in excited-state lifetime was reflected in the photosensitizing ability of complexes 1-5 in visible-light-driven hydrogen generation using sodium ascorbate and a cobalt(III) diglyoxime complex as an electron donor and a water-reduction catalyst, respectively. This study suggests that the SCMB method should be generally effective in controlling the excited state of other bis-cyclometalated cationic Ir(III) complexes.

  4. Solution-phase mechanistic study and solid-state structure of a tris(bipyridinium radical cation) inclusion complex.

    Science.gov (United States)

    Fahrenbach, Albert C; Barnes, Jonathan C; Lanfranchi, Don Antoine; Li, Hao; Coskun, Ali; Gassensmith, Jeremiah J; Liu, Zhichang; Benítez, Diego; Trabolsi, Ali; Goddard, William A; Elhabiri, Mourad; Stoddart, J Fraser

    2012-02-15

    The ability of the diradical dicationic cyclobis(paraquat-p-phenylene) (CBPQT(2(•+))) ring to form inclusion complexes with 1,1'-dialkyl-4,4'-bipyridinium radical cationic (BIPY(•+)) guests has been investigated mechanistically and quantitatively. Two BIPY(•+) radical cations, methyl viologen (MV(•+)) and a dibutynyl derivative (V(•+)), were investigated as guests for the CBPQT(2(•+)) ring. Both guests form trisradical complexes, namely, CBPQT(2(•+))⊂MV(•+) and CBPQT(2(•+))⊂V(•+), respectively. The structural details of the CBPQT(2(•+))⊂MV(•+) complex, which were ascertained by single-crystal X-ray crystallography, reveal that MV(•+) is located inside the cavity of the ring in a centrosymmetric fashion: the 1:1 complexes pack in continuous radical cation stacks. A similar solid-state packing was observed in the case of CBPQT(2(•+)) by itself. Quantum mechanical calculations agree well with the superstructure revealed by X-ray crystallography for CBPQT(2(•+))⊂MV(•+) and further suggest an electronic asymmetry in the SOMO caused by radical-pairing interactions. The electronic asymmetry is maintained in solution. The thermodynamic stability of the CBPQT(2(•+))⊂MV(•+) complex was probed by both isothermal titration calorimetry (ITC) and UV/vis spectroscopy, leading to binding constants of (5.0 ± 0.6) × 10(4) M(-1) and (7.9 ± 5.5) × 10(4) M(-1), respectively. The kinetics of association and dissociation were determined by stopped-flow spectroscopy, yielding a k(f) and k(b) of (2.1 ± 0.3) × 10(6) M(-1) s(-1) and 250 ± 50 s(-1), respectively. The electrochemical mechanistic details were studied by variable scan rate cyclic voltammetry (CV), and the experimental data were compared digitally with simulated data, modeled on the proposed mechanism using the thermodynamic and kinetic parameters obtained from ITC, UV/vis, and stopped-flow spectroscopy. In particular, the electrochemical mechanism of association

  5. Heteroleptic cyclometalated iridium(III) complexes displaying blue phosphorescence in solution and solid state at room temperature.

    Science.gov (United States)

    Yang, Cheng-Han; Li, Shih-Wen; Chi, Yun; Cheng, Yi-Ming; Yeh, Yu-Shan; Chou, Pi-Tai; Lee, Gene-Hsiang; Wang, Chih-Hsiang; Shu, Ching-Fong

    2005-10-31

    A series of heteroleptic Ir(III) metal complexes 1-3 bearing two N-phenyl-substituted pyrazoles and one 2-pyridyl pyrazole (or triazole) ligands were synthesized and characterized to attain highly efficient, room-temperature blue phosphorescence. The N-phenylpyrazole ligands, dfpzH = 1-(2,4-difluorophenyl)pyrazole, fpzH = 1-(4-fluorophenyl)pyrazole, dfmpzH = 1-(2,4-difluorophenyl)-3,5-dimethylpyrazole, and fmpzH = 1-(4-fluorophenyl)-3,5-dimethylpyrazole, show a similar reaction pattern with respect to the typical cyclometalated (C(wedge)N) chelate, which utilizes its ortho-substituted phenyl segment to link with the central Ir(III) atom, while the second 2-pyridylpyrazole (or triazole) ligand, namely, fppzH = 3-(trifluoromethyl)-5-(2-pyridyl)pyrazole, fptzH = 3-(trifluoromethyl)-5-(2-pyridyl)triazole, and hptzH = 3-(heptafluoropropyl)-5-(2-pyridyl)triazole, undergoes typical anionic (N--N) chelation to complete the octahedral framework. X-ray structural analyses on complexes [(dfpz)(2)Ir(fppz)] (1a) and [(fmpz)(2)Ir(hptz)] (3d) were established to confirm their molecular structures. Increases of the pipi energy gaps of the Ir(III) metal complexes were systematically achieved with two tuning strategies. One involves the substitution for one or two fluorine atoms at the N-phenyl segment or the introduction of two electron-releasing methyl substituents at the pyrazole segment of the H(C--N) ligands. Alternatively, we have applied the more electron-accepting triazolate in place of the pyrazolate segment for the third (N--N)H ligand. Our results, on the basis of steady-state, relaxation dynamics, and theoretical approaches, lead to a conclusion that, for complexes 1-3, the weakening of iridium metal-ligand bonding strength in the T(1) state plays a crucial role for the fast radiationless deactivation. For the case of [(fmpz)(2)Ir(hptz)] (3d), a thermal deactivation barrier of 4.8 kcal/mol was further deduced via temperature-dependent studies. The results provide a

  6. The Complex Spin State of 103P-Hartley 2: Kinematics and Orientation in Space

    Science.gov (United States)

    Belton, Michael J. S.; Thomas, Peter; Li, Jian-Yang; Williams, Jade; Carcich, Brian; A'Hearn, Michael F.; McLaughlin, Stephanie; Farnham, Tony; McFadden, Lucy; Lisse, Carey M.; Collins, Steven; Besse, Sebastien; Klaasen, Kenneth; Sunshine, Jessica; Meech, Karen J.; Lindler, Don

    2013-01-01

    We derive the spin state of the nucleus of Comet 103P/Hartley 2, its orientation in space, and its short-term temporal evolution from a mixture of observations taken from the DIXI (Deep Impact Extended Investigation) spacecraft and radar observations. The nucleus is found to spin in an excited long-axis mode (LAM) with its rotational angular momentum per unit mass, M, and rotational energy per unit mass, E, slowly decreasing while the degree of excitation in the spin increases through perihelion passage. M is directed toward (RA, Dec; J2000) = 8+/-+/- 4 deg., 54 +/- 1 deg. (obliquity = 48 +/- 1 deg.). This direction is likely changing, but the change is probably <6 deg. on the sky over the approx. 81.6 days of the DIXI encounter. The magnitudes of M and E at closest approach (JD 2455505.0831866 2011-11-04 13:59:47.310) are 30.0 +/- 0.2 sq. m/s and (1.56 +/- 0.02) X 10(exp -3) sq. m /sq. s respectively. The period of rotation about the instantaneous spin vector, which points in the direction (RA, Dec; J2000) = 300 +/- 3.2deg., 67 +/- 1.3 deg. at the time of closest approach, was 14.1 +/- 0.3 h. The instantaneous spin vector circulates around M, inclined at an average angle of 33.2 +/- 1.3 deg. with an average period of 18.40 +/- 0.13 h at the time of closest approach. The period of roll around the principal axis of minimum inertia (''long'' axis) at that time is 26.72 +/- 0.06 h. The long axis is inclined to M by approx. 81.2 +/- 0.6 deg. on average, slowly decreasing through encounter. We infer that there is a periodic nodding motion of the long axis with half the roll period, i.e., 13.36+/- 0.03 h, with amplitude of 1 again decreasing through encounter. The periodic variability in the circulation and roll rates during a cycle was at the 2% and 10-14% level respectively. During the encounter there was a secular lengthening of the circulation period of the long axis by 1.3 +/- 0.2 min/d, in agreement with ground-based estimates, while the period of roll around the

  7. Tetrakis(dimethoxyphenyl)adamantane (TDA) and its inclusion complexes in the crystalline state: a versatile carrier for small molecules.

    Science.gov (United States)

    Schwenger, Alexander; Frey, Wolfgang; Richert, Clemens

    2015-06-08

    Molecular storage solutions for incorporating small molecules in crystalline matrices are of interest in the context of structure elucidation, decontamination, and slow release of active ingredients. Here we report the syntheses of 1,3,5,7-tetrakis(2,4-dimethoxyphenyl)adamantane, 1,3,5,7-tetrakis(4-methoxyphenyl)adamantane, 1,3,5,7-tetrakis(4-methoxy-2-methylphenyl)adamantane, and 1,3,5,7-tetrakis(4-methoxy-2-ethylphenyl)adamantane, together with their X-ray crystal structures. All four compounds crystallize readily. Only the octaether shows an unusual level of (pseudo)polymorphism in its crystalline state, combined with the ability to include a number of different small molecules in its crystal lattices. A total of 20 different inclusion complexes with guest molecules as different as ethanol or trifluorobenzene were found. For nitromethane and benzene, schemes for uptake and release are presented.

  8. Event-based state estimation for a class of complex networks with time-varying delays: A comparison principle approach

    Science.gov (United States)

    Zhang, Wenbing; Wang, Zidong; Liu, Yurong; Ding, Derui; Alsaadi, Fuad E.

    2017-01-01

    The paper is concerned with the state estimation problem for a class of time-delayed complex networks with event-triggering communication protocol. A novel event generator function, which is dependent not only on the measurement output but also on a predefined positive constant, is proposed with hope to reduce the communication burden. A new concept of exponentially ultimate boundedness is provided to quantify the estimation performance. By means of the comparison principle, some sufficient conditions are obtained to guarantee that the estimation error is exponentially ultimately bounded, and then the estimator gains are obtained in terms of the solution of certain matrix inequalities. Furthermore, a rigorous proof is proposed to show that the designed triggering condition is free of the Zeno behavior. Finally, a numerical example is given to illustrate the effectiveness of the proposed event-based estimator.

  9. The Dissociative Subtype of Posttraumatic Stress Disorder: Unique Resting-State Functional Connectivity of Basolateral and Centromedial Amygdala Complexes.

    Science.gov (United States)

    Nicholson, Andrew A; Densmore, Maria; Frewen, Paul A; Théberge, Jean; Neufeld, Richard Wj; McKinnon, Margaret C; Lanius, Ruth A

    2015-09-01

    Previous studies point towards differential connectivity patterns among basolateral (BLA) and centromedial (CMA) amygdala regions in patients with posttraumatic stress disorder (PTSD) as compared with controls. Here we describe the first study to compare directly connectivity patterns of the BLA and CMA complexes between PTSD patients with and without the dissociative subtype (PTSD+DS and PTSD-DS, respectively). Amygdala connectivity to regulatory prefrontal regions and parietal regions involved in consciousness and proprioception were expected to differ between these two groups based on differential limbic regulation and behavioral symptoms. PTSD patients (n=49) with (n=13) and without (n=36) the dissociative subtype and age-matched healthy controls (n=40) underwent resting-state fMRI. Bilateral BLA and CMA connectivity patterns were compared using a seed-based approach via SPM Anatomy Toolbox. Among patients with PTSD, the PTSD+DS group exhibited greater amygdala functional connectivity to prefrontal regions involved in emotion regulation (bilateral BLA and left CMA to the middle frontal gyrus and bilateral CMA to the medial frontal gyrus) as compared with the PTSD-DS group. In addition, the PTSD+DS group showed greater amygdala connectivity to regions involved in consciousness, awareness, and proprioception-implicated in depersonalization and derealization (left BLA to superior parietal lobe and cerebellar culmen; left CMA to dorsal posterior cingulate and precuneus). Differences in amygdala complex connectivity to specific brain regions parallel the unique symptom profiles of the PTSD subgroups and point towards unique biological markers of the dissociative subtype of PTSD.

  10. International competitiveness of brazilian and paraná state`s coffe complex / Competitividade internacional do complexo cafeeiro brasileiro e paranaense

    Directory of Open Access Journals (Sweden)

    Marcela Vasques Cintra

    2008-08-01

    Full Text Available The objective of this article is to analyze the determinants aspects of the competitiveness of the exportations of the coffee complex in Paraná State between 1990 and 2003 . The study intends to systematize: the recent literature on the subject, focusing the competitiveness of the main products of the brazilian guideline of exportations. A critical review of literature was made about the theories of international trade and competitiveness. It was characterized the dynamics of the complex of Brazilian coffee. The article identifies the competitive advantages of the Paraná coffee (green, roasted, soluble and special in relation to the competing countries; discusses the barriers to imports imposed to the brazilian coffee by the importing countries, and ends with the possible public and private policies favorable to the competitiveness of the coffee exportations.O objetivo deste artigo é analisar os determinantes da competitividade das exportações do complexo cafeeiro paranaense entre 1990 e 2003. O estudo pretende sistematizar: a literatura recente sobre o tema, enfocando a competitividade de um dos principais produtos da pauta de exportações brasileira e do Paraná. Realizou-se a revisão crítica da literatura das teorias do comércio internacional e da competitividade e em seguida, caracterizou-se a dinâmica do complexo cafeeiro do brasileiro e paranaense. O artigo identifica as vantagens competitivas do café paranaense (verde, torrado, solúvel e especial em relação aos países concorrentes; discute as barreiras às importações impostas ao café brasileiro pelos países importadores; e finaliza com as possíveis políticas públicas e privadas favoráveis à competitividade das exportações de café.

  11. Steady state and time-resolved fluorescence spectroscopy of quinine sulfate dication bound to sodium dodecylsulfate micelles: Fluorescent complex formation

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Sunita; Pant, Debi D., E-mail: ddpant@pilani.bits-pilani.ac.in

    2014-01-15

    Interaction of quinine sulfate dication (QSD) with anionic, sodium dodecylsulphate (SDS) surfactant has been studied at different premicellar, micellar and postmicellar concentrations in aqueous phase using steady state, time-resolved fluorescence and fluorescence anisotropy techniques. At premicellar concentrations of SDS, the decrease in absorbance, appearance of an extra fluorescence band at lower wavelengths and tri-exponential decay behavior of fluorescence, are attributed to complex formation between QSD molecules and surfactant monomers. At postmicellar concentrations the red shift in fluorescence spectrum, increase in quantum yield and increase in fluorescence lifetimes are attributed to incorporation of solute molecules to micelles. At lower concentrations of SDS, a large shift in fluorescence is observed on excitation at the red edge of absorption spectrum and this is explained in terms of distribution of ion pairs of different energies in the ground state and the observed fluorescence lifetime behavior corroborates with this model. The temporal fluorescence anisotropy decay of QSD in SDS micelles allowed determination of restriction on the motion of the fluorophore. All the different techniques used in this study reveal that the photophysics of QSD is very sensitive to the microenvironments of SDS micelles and QSD molecules reside at the water-micelle interface. -- Highlights: • Probe molecule is very sensitive to microenvironment of micelles. • Highly fluorescent ion-pair formation has been observed. • Modulated photophysics of probe molecule in micellar solutions has been observed. • Probe molecules strongly bind with micelles and reside at probe–micelle interface.

  12. Quantizing the Complexity of the Western United States Fault System with Geodetically and Geologically Constrained Block Models

    Science.gov (United States)

    Evans, E. L.; Meade, B. J.

    2014-12-01

    Geodetic observations of interseismic deformation provide constraints on miroplate rotations, earthquake cycle processes, slip partitioning, and the geometric complexity of the Pacific-North America plate boundary. Paleoseismological observations in the western United States provide a complimentary dataset of Quaternary fault slip rate estimates. These measurements may be integrated and interpreted using block models, in which the upper crust is divided into microplates bounded by mapped faults, with slip rates defined by the differential relative motions of adjacent microplates. The number and geometry of microplates are typically defined with boundaries representing a limited sub-set of the large number of potentially seismogenic faults. An alternative approach is to include large number of potentially active faults in a dense array of microplates, and then deterministically estimate the boundaries at which strain is localized, while simultaneously satisfying interseismic geodetic and geologic observations. This approach is possible through the application of total variation regularization (TVR) which simultaneously minimizes the L2 norm of data residuals and the L1 norm of the variation in the estimated state vector. Applied to three-dimensional spherical block models, TVR reduces the total variation between estimated rotation vectors, creating groups of microplates that rotate together as larger blocks, and localizing fault slip on the boundaries of these larger blocks. Here we consider a suite of block models containing 3-137 microplates, where active block boundaries have been determined by TVR optimization constrained by both interseismic GPS velocities and geologic slip rate estimates.

  13. Structure and excited state relaxation dynamics in nanoscale self-assembled arrays: multiporphyrin complexes, porphyrin-quantum dot composites

    Science.gov (United States)

    Zenkevich, E. I.; von Borczyskowski, C.

    2005-06-01

    Self-assembled nanoscale arrays of controllable geometry and composition (up to 8 tetrapyrroles) have been formed via non-covalent binding interactions of the meso-phenyl bridged Zn-octaethylporphyrin chemical dimers or trimers with di- /tetrapyridyl substituted porphyrin extra-ligands. In these complexes using steady-state and time-resolved (ps fluorescence and fs pump-probe) measurements pathways and efficiencies of the energy transfer photoinduced charge separation as well as exchange d-π effects have been studied in solutions of variable polarity at 77-293 K. The same principles of aggregation via the key-hole scheme "Zn-pyridyl" have been used also for the surface passivation of pyridylsubstituted tetrapyrroles on the coreshell semiconductor CdSe/ZnS quantum dots (QD) showing quantum confinement effects. Picosecond time-resolved and steady-state data reveal that CdSe/ZnS QD emission is multiexponential and the efficiency of its quenching by attached porphyrins (due to energy transfer and photoinduced charge separation) depends strongly on the number of anchoring groups their arrangement in the porphyrin molecule as well as on QD size and number of ZnS monolayers. The analysis of spectroscopic and kinetic findings reveals that on average only ~l/5 porphyrin molecules are assembled on the QD and a limited number of "vacancies" accessible for porphyrin attachment is available on the QD surface.

  14. Correlations between (51)V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts.

    Science.gov (United States)

    Fenn, Annika; Wächtler, Maria; Gutmann, Torsten; Breitzke, Hergen; Buchholz, Axel; Lippold, Ines; Plass, Winfried; Buntkowsky, Gerd

    2009-12-01

    The parameters describing the quadrupolar and CSA interactions of 51V solid-state MAS NMR investigations of model complexes mimicking vanadoenzymes as well as vanadium containing catalysts and enzyme complexes are interpreted with respect to the chemical structure. The interpretation is based on the data of 15 vanadium complexes including two new complexes with previously unpublished data and 13 complexes with data previously published by us. Correlations between the chemical structure and the 51V solid-state NMR data of this class of compounds have been established. Especially for the isotropic chemical shift delta(iso) and the chemical shift anisotropy delta(sigma), correlations with specific structural features like the coordination number of the vanadium atom, the number of coordinating nitrogens, the number of oxygen atoms and the chemical surrounding of the complex could be established for these compounds. Moreover, quantitative correlations between the solid-state NMR parameters and specific bond angles and bond lengths have been obtained. Our results can be of particular interest for future investigations concerning the structure and the mode of action of related vanadoenzymes and vanadate protein assemblies, including the use of vanadate adducts as transition state analogs for phosphate metabolizing systems.

  15. Waste is a Terrible Thing to Mind: Perspectives on the Cleanup of the United States Nuclear Weapons Complex

    Science.gov (United States)

    Bodde, David

    1997-03-01

    For the 50 years of the Cold War, the United States nuclear arsenal was the cornerstone of our national security. These weapons were designed, manufactured, and armed with fissionable materials in an industrial complex that, at its peak, included about 16 major facilities and vast tracts of land in Nevada, Idaho, Washington, and South Carolina. Included among these are such well-known sites as the Savannah River Plant, the Hanford, Oak Ridge, and the Idaho National Engineering Laboratory. The Cold War, that "long twilight struggle" in the evocative phrase of John Kennedy, left little time and few resources for understanding and managing the environmental consequences of nuclear weapons production. At the same time, perceptions of the special nature of the atom led to a concentration of governance in the Atomic Energy Commission and the Joint Committee on Atomic Energy. Thus, external feedback for the managers of the complex was heavily filtered. But the imperatives of the Cold War have waned, and our understanding of the implications for the environment and the health and safety of workers has grown. By 1995 the Department of Energy (DoE) had spent about 23 billion in identifying and characterizing its waste, managing it, and assessing the actions needed to clean up the 120 sites in 36 states. Yet the majority of the task appeared ahead. Estimates made in 1995 suggested a total cost ranging from 200-350 billion and a time to complete of 75 years. If these were true, the cleanup of the weapons complex would become the largest civil works project in the history of humankind. Over the past year or so, the DoE program has shifted its focus from studies to actual cleanup. A strategic plan has been proposed that would accomplish most of the needed work over ten years at a cost of about $85 billion. At the same time, the Department is proposing to transfer oversight to the Nuclear Regulatory Commission, the Environmental Protection Agency, and the states. This Invited

  16. Mechanochemically assisted solid-state and citric acid complex syntheses of Cu-doped sodium cobaltite ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Pršić, S., E-mail: sanjaprsic@imsi.bg.ac.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade (Serbia); Savić, S.M., E-mail: slavicas@imsi.bg.ac.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade (Serbia); Branković, Z., E-mail: zorica.brankovic@imsi.bg.ac.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade (Serbia); Vrtnik, S., E-mail: stane.vrtnik@ijs.si [Institute Jožef Stefan, Condensed Matter Physics, Jamova cesta 39, 1000 Ljubljana (Slovenia); Dapčević, A., E-mail: hadzi-tonic@tmf.bg.ac.rs [Department of General and Inorganic Chemistry, Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11120 Belgrade (Serbia); Branković, G., E-mail: goran.brankovic@imsi.bg.ac.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade (Serbia)

    2015-08-15

    Highlights: • Sodium cobaltite was synthesized by mechanochemically assisted solid-state reaction and citric acid complex (CAC) method. • We investigated effect of Cu-doping in NaCo{sub 2−x}Cu{sub x}O{sub 4} (x = 0, 0.01, 0.03, 0.05). • ICP analysis showed that the controlling of the samples composition is easier by the CAC method. • The Seebeck coefficient in Cu-doped samples was higher compared to the undoped one. • The highest figure of merit was observed in the sample with the lowest Cu concentration. - Abstract: In the last decade, the sodium cobaltite ceramic became a promising candidate for potential thermoelectric applications, because of its large thermopower and low resistivity. In this work, polycrystalline samples of NaCo{sub 2−x}Cu{sub x}O{sub 4} (x = 0, 0.01, 0.03, 0.05) were prepared using mechanochemically assisted solid-state reaction method (MASSR) and the citric acid complex method (CAC). Bulk samples were prepared by pressing into disc-shaped pellets and subsequently subjected to a thermal treatment at 880 °C in inert argon atmosphere. Changes in structural and microstructural characteristics of the samples, caused by the substitution of Cu for Co, were characterized using X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM), respectively. The results of inductively coupled plasma (ICP) analysis showed that the compositions of the final products correspond to γ-NaCo{sub 2}O{sub 4} and confirmed that desired compound was obtained in both syntheses procedures. The advantages and disadvantages of these two syntheses procedures have been observed and discussed: the CAC method enabled obtaining samples with higher density and fine microstructure compared to the MASSR method, thus better thermoelectric properties. The Cu{sup 2+} substitution led to the increase in Seebeck coefficient in both synthesis routes. The highest figure of merit of 0.022 at 300 K was observed for the sample doped with 1 mol% Cu, obtained by

  17. Nickel(II) complexes having Imidazol-2-ylidene-N′-phenylurea ligand in the coordination sphere – syntheses and solid state structures

    Indian Academy of Sciences (India)

    Kishor Naktode; Abhinanda Kundu; Sudeshna Saha; Hari Pada Nayek; Tarun K Panda

    2015-08-01

    We report the syntheses and structural studies of two nickel(II) complexes of imidazol-2-ylidene- N'-phenylureate ligand of composition [{ImBu NCON(H)Ph}2 Ni(acac)2] (1) and [(C6H5NH2)2 Ni(acac)2] [ImMes NCON(H)Ph] (2). The nickel complex 1 was readily prepared by the reaction of nickel(II) acetylacetonate [Ni(acac) 2 ] with imidazol-2-ylidene-N'-phenylureate ligand [ImBu NCON(H)Ph] (L1) in THF under reflux condition for 72 h. The nickel complex 2 was obtained by the reaction of [Ni(acac)2], mesityl derivative of imidazol-2-ylidene-N′-phenylureate ligand [ImMes NCON(H)Ph] (L2) in the presence of aniline as base under reflux condition in THF. Both the paramagnetic complexes have been characterized by FT-IR spectroscopy and elemental analyses. Solid-state structures of both the new complexes were established by single crystal X-ray diffraction analysis. In the molecular structures of complexes 1 and 2, each nickel(II) ion is six fold coordinated and form a distorted octahedral geometry. The optical properties of both complexes have been explored. The Hirshfeld surfaces are used to view and analyze the intermolecular contacts in crystalline state for complex 2.

  18. Resonance Raman spectra of TNT and RDX using vibronic theory, excited-state gradient, and complex polarizability approximations.

    Science.gov (United States)

    Al-Saidi, W A; Asher, Sanford A; Norman, Patrick

    2012-08-02

    Geometries, UV absorption bands, and resonance Raman (RR) cross sections of TNT and RDX are investigated using density functional theory (DFT) in conjunction with the Coulomb attenuated B3LYP exchange-correlation functional. The absorption and RR spectra are determined with use of vibronic (VB) theory, excited-state gradient, and complex polarizability (CPP) approximations. We examined low-energy isomers (two for TNT and four for RDX) whose energies differ by less than 1 kcal/mol, such that they would appreciably be populated at room temperature. The two TNT isomers differ by an internal rotation of the methyl group, while the four conformers of RDX differ by the arrangements of the nitro group relative to the ring. Our theoretical optical properties of the TNT and RDX isomers are in excellent agreement with experimental and recent CCSD-EOM results, respectively. For the two TNT isomers, the ultraviolet RR (UVRR) spectra are similar and in good agreement with recently measured experimental results. Additionally, the UVRR spectra computed using the excited-state and CPP approaches compare favorably with the VB theory results. On the other hand, the RR spectra of the RDX conformers differ from one another, reflecting the importance of the positioning of the NO2 groups with respect to the ring. In the gas phase or in solution, RDX would give a spectrum associated with a conformationally averaged structure. It is encouraging that the computed spectra of the conformers show similarities to recent measured RDX spectra in acetonitrile solution, and reproduce the 10-fold decrease in the absolute Raman cross sections of RDX compared to TNT for the observed 229 nm excitation. We show that in TNT and RDX vibrational bands that couple to NO2 or the ring are particularly resonance enhanced. Finally, the computed RDX spectra of the conformers present a benchmark for understanding the RR spectra of the solid-phase polymorphs of RDX.

  19. Modernization of the Mechanism of State Regulation of Regional Russian Agro-Industrial Complex Under New Social and Economic Constructs

    Directory of Open Access Journals (Sweden)

    Babich Tatyana Vladimirovna

    2014-11-01

    Full Text Available The article highlights the obstacles in building the necessary amount of food and in ensuring the full import substitution based on the efficient use of the available resources: Russia’s lagging behind economically developed countries in the technical and technological modernization of agricultural sectors; low-rate processes of production intensification in the ongoing targeted programs; insufficient use of existing competitive advantages of individual regions. Consequently, in the current environment of increased competition between agricultural commodity producers of different countries, the mechanism of Russian agriculture state support needs to be improved. Based on the analysis of threats due to Russia’s entry into the WTO in terms of sanctions imposed by the European Union in relation to the events in Ukraine, the authors proposed and justified measures aimed at modernizing the mechanism of state regulation of regional agriculture of Russia in the new economic and social constructs. In order to develop a high-tech industrial chain in agricultural business, the authors have developed the mechanism of functioning production and logistics agrocenter organized to bring together competences and cooperation between enterprises in different industries. Agrocenter is a special investment area, which should be provided with all necessary infrastructure and professional management for subsequent placement on the same territory: commercial resident working in the agricultural sector; commercial residents working in the transport and warehouse complex; financial market enterprises and organizations for quality control and certification; consulting firms for the development and promotion agrocenter; consumers of agricultural products: manufacturing, wholesale and retail, commercial enterprises, social sphere.

  20. Genetic diversity of Mycobacterium tuberculosis complex strains isolated from patients with pulmonary tuberculosis in Anambra State, Nigeria.

    Science.gov (United States)

    Uzoewulu, Gertrude N; Lawson, Lovett; Nnanna, Ibeh S; Rastogi, Nalin; Goyal, Madhu

    2016-03-01

    In this study, we analyzed Mycobacterium tuberculosis complex (MTC) genetic diversity in Anambra State, Nigeria based on spoligotyping followed by 5-loci exact tandem repeats (ETRs). Spoligotyping of 180 MTC strains isolated in 2009-2011 from pulmonary tuberculosis (TB) patients led to a total of 31 distinct patterns. A comparison with the SITVIT2 international database showed that all the 31 patterns could be classified as Shared-types (SITs) in this database; briefly, 26/31 SITs (n=174 isolates) matched a preexisting shared-type in the database, whereas 5/31 SITs (n=6 isolates) were newly created due to 2 or more strains belonging to an identical new pattern within this study (SIT3396) or after a match with an orphan in the database (SIT3397, SIT3398, SIT3399 and SIT3400). A total of 18/31 SITs containing 167 or 92.8% isolates were clustered within this study (2-89 isolates per cluster) while 13/31 SITs contained unique strains. Using VNTR typing, a total of 36 distinct patterns were identified; 27 patterns (n=157 isolates) matched a pattern already reported in the SITVIT2 database. Combination of both the methods generated 47 combined patterns for the 180 strains: 17 belonged to clustered isolates (n=127 isolates or 70.5%) while 30 corresponded to as many unique strains (note 23 strains could not be typed using 5-loci ETRs). No correlation was found between the spoligotyping pattern and the HIV status of the patient or drug sensitivity of the strain. This study showed that the LAM10-CAM prototype SIT61 accounted for highest number of isolates (n=89) in Anambra State, showing its relative contribution to the TB burden in the study.

  1. Unique insula subregion resting-state functional connectivity with amygdala complexes in posttraumatic stress disorder and its dissociative subtype.

    Science.gov (United States)

    Nicholson, Andrew A; Sapru, Iman; Densmore, Maria; Frewen, Paul A; Neufeld, Richard W J; Théberge, Jean; McKinnon, Margaret C; Lanius, Ruth A

    2016-04-30

    The insula and amygdala are implicated in the pathophysiology of posttraumatic stress disorder (PTSD), where both have been shown to be hyper/hypoactive in non-dissociative (PTSD-DS) and dissociative subtype (PTSD+DS) PTSD patients, respectively, during symptom provocation. However, the functional connectivity between individual insula subregions and the amygdala has not been investigated in persons with PTSD, with or without the dissociative subtype. We examined insula subregion (anterior, mid, and posterior) functional connectivity with the bilateral amygdala using a region-of-interest seed-based approach via PickAtlas and SPM8. Resting-state fMRI was conducted with (n=61) PTSD patients (n=44 PTSD-DS; n=17 PTSD+DS), and (n=40) age-matched healthy controls. When compared to controls, the PTSD-DS group displayed increased insula connectivity (bilateral anterior, bilateral mid, and left posterior) to basolateral amygdala clusters in both hemispheres, and the PTSD+DS group displayed increased insula connectivity (bilateral anterior, left mid, and left posterior) to the left basolateral amygdala complex. Moreover, as compared to PTSD-DS, increased insula subregion connectivity (bilateral anterior, left mid, and right posterior) to the left basolateral amygdala was found in PTSD+DS. Depersonalization/derealization symptoms and PTSD symptom severity correlated with insula subregion connectivity to the basolateral amygdala within PTSD patients. This study is an important first step in elucidating patterns of neural connectivity associated with unique symptoms of arousal/interoception, emotional processing, and awareness of bodily states, in PTSD and its dissociative subtype. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Balanço de energia em um solo cultivado com feijão caupi no brejo paraibano Energy balance in a soil cultivated with cowpeas in a mountaineous area in Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    José R. de S. Lima

    2005-12-01

    Full Text Available Os componentes do balanço de energia num solo cultivado com feijão caupi nas condições do Brejo Paraibano, foram determinados numa área de 4 ha do Centro de Ciências Agrárias, da UFPB, localizada no município de Areia, PB (6o 58' S, 35o 41' W e 620 m. Para tal, instalou-se uma torre no centro da área, contendo um pluviógrafo, um piranômetro, um saldo radiômetro e sensores para medida da temperatura e da umidade relativa do ar, em dois níveis acima do dossel da cultura; além disso, dois locais no solo foram instrumentados, cada um com duas sondas térmicas instaladas horizontalmente, nas profundidades de z1 = 2,0 cm e z2 = 8,0 cm, além de uma placa destinada à medida do fluxo de calor no solo, a 5,0 cm. Essas medidas foram armazenadas a cada 30 min, num sistema de aquisição de dados. Verificou-se que o valor médio do saldo de radiação (Rn foi de 78%, sendo a Rn utilizada, em média, como 71% no fluxo de calor latente (LE, 19% como fluxo de calor sensível (H e 10% como fluxo de calor no solo (G. A fração do saldo de radiação utilizada como fluxo de calor latente aumentou com a evolução da cobertura do solo pela cultura, enquanto a fração utilizada como fluxo de calor sensível e de calor no solo, diminuiu.The energy balance components in a cowpea crop growing in the mountain region of Paraiba, Brazil ("Brejo Paraibano" was determined in a 4 ha area in the Centro de Ciências Agrárias, UFPB, in the municipality of Areia, PB (6o 58' S, 35o 41' W e 620 m. Measurements of rainfall, net and global radiation were made. Sensors at two levels above the canopy were also mounted, allowing the measurements of air temperature and relative humidity. Below the soil surface, two different sites were provided with two thermal probes, horizontally installed at depths of 2.0 and 8.0 cm, besides a heat flux plate 5.0 cm deep for soil heat flux measurements. All data were stored in a datalogger each 30 min. The average value of the net

  3. Ternary inclusion complex formation and stabilization of limaprost, a prostaglandin E1 derivative, in the presence of α- and β-cyclodextrins in the solid state.

    Science.gov (United States)

    Inoue, Yasuo; Iohara, Daisuke; Sekiya, Noboru; Yamamoto, Masanobu; Ishida, Hiroyuki; Sakiyama, Yoko; Hirayama, Fumitoshi; Arima, Hidetoshi; Uekama, Kaneto

    2016-07-25

    Limaprost/α-cyclodextrin (CD)/β-CD ternary inclusion complex was prepared by freeze-drying a solution containing all three components. Under humid conditions, limaprost was more stable in the ternary α-/β-CD inclusion complex than in the binary α- or β-CD complex. Specifically, during storage at 30°C/75% relative humidity (R.H.) for 4 weeks, about 19% of limaprost degraded into 17S,20-dimethyl-trans-Δ(2)-prostaglandin A1 (referred as 11-deoxy-Δ(10)) in the β-CD complex, 8.1% degraded in the α-CD complex, and only 2.2% degraded in the α-/β-CD complex. The mechanism of limaprost stabilization in the presence of both CDs was investigated by Raman and solid-state NMR spectroscopy and powder X-ray diffractometry. The fast degradation of limaprost to 11-deoxy-Δ(10) in the β-CD complex was due to the rapid crystallization of β-CD from the complex, liberating the free amorphous drug, which is susceptible to degradation. The dissociation and crystallization of β-CD from the inclusion complex were suppressed by freeze-drying limaprost in the presence of both α- and β-CDs. In addition, the interaction between limaprost and the two CDs was reinforced by inclusion of different moieties of limaprost: α-CD predominantly included the alkyl ω-chain, whereas β-CD included the five-membered ring. Thus, a stable ternary inclusion complex was formed that included limaprost, maintaining the amorphous state of the complex and dramatically stabilizing the drug under humid conditions.

  4. A total quasi-steady-state formulation of substrate uptake kinetics in complex networks and an example application to microbial litter decomposition

    OpenAIRE

    Tang, J Y; Riley, W.J.

    2013-01-01

    We demonstrate that substrate uptake kinetics in any consumer–substrate network subject to the total quasi-steady-state assumption can be formulated as an equilibrium chemistry (EC) problem. If the consumer-substrate complexes equilibrate much faster than other metabolic processes, then the relationships between consumers, substrates, and consumer-substrate complexes are in quasi-equilibrium and the change of a given total substrate (free plus consumer-bounded) is determined...

  5. A total quasi-steady-state formulation of substrate uptake kinetics in complex networks and an example application to microbial litter decomposition

    OpenAIRE

    Tang, J Y; Riley, W.J.

    2013-01-01

    We demonstrate that substrate uptake kinetics in any consumer-substrate network subject to the total quasi-steady-state assumption can be formulated as an equilibrium chemistry (EC) problem. If the consumer-substrate complexes equilibrate much faster than other metabolic processes, then the relationships between consumers, substrates, and consumer-substrate complexes are in quasi-equilibrium and the change of a given total substrate (free plus consumer-bounded) is determined by the deg...

  6. C-HCl(-) hydrogen bonds in solution and in the solid-state: HgCl2 complexes with cyclen-based cryptands.

    Science.gov (United States)

    Ikeda, Mari; Sah, Ajay Kumar; Iwase, Miki; Murashige, Rina; Ishi-I, Jun-Ichi; Hasegawa, Masatoshi; Kachi-Terajima, Chihiro; Park, Ki-Min; Kuwahara, Shunsuke; Habata, Yoichi

    2017-03-21

    Structural evidence is reported for C-HCl(-) hydrogen bonds in solution and in the solid state of HgCl2 complexes with cyclen-based cryptands. These cyclen-based cryptands (1) and (2) are bridged by di- and triethylene glycol units, respectively, between two aromatic rings. The X-ray structure indicates that the 2/HgCl2 complex contains an acetonitrile molecule in the cavity.

  7. Factors Affecting the Efficiency of Excited-States Interactions of Complexes between Some Visible Light-Emitting Lanthanide Ions and Cyclophanes Containing Spirobiindanol Phosphonates

    Directory of Open Access Journals (Sweden)

    M. S. Attia

    2007-01-01

    Full Text Available The efficiency of excited-states interactions between lanthanide ions Tb3+ and Eu3+ and some new cyclophanes (I, II, and III has been studied in different media. High luminescence quantum yield values for terbium and europium complexes in DMSO and PMMA were obtained. The photophysical properties of the green and red emissive Tb3+ and Eu3+ complexes have been elucidated, respectively.

  8. The orbital ground state of the azide-substrate complex of human heme oxygenase is an indicator of distal H-bonding: Implications for the enzyme mechanism‡

    Science.gov (United States)

    Ogura, Hiroshi; Evans, John P.; Peng, Dungeng; Satterlee, James D.; de Montellano, Paul R. Ortiz; Mar, Gerd N. La

    2009-01-01

    The active site electronic structure of the azide complex of substrate-bound human heme oxygenase-1, (hHO) has been investigated by 1H NMR spectroscopy to shed light on the orbital/spin ground state as an indicator of the unique distal pocket environment of the enzyme. 2D 1H NMR assignments of the substrate and substrate-contact residue signals reveal a pattern of substrate methyl contact shifts, that places the lone iron π-spin in the dxz orbital, rather than the dyz orbital found in the cyanide complex. Comparison of iron spin relaxivity, magnetic anisotropy and magnetic susceptibilities argues for a low-spin, (dxy)2(dyz,dxz)3, ground state in both azide and cyanide complexes. The switch from singly-occupied dyz for the cyanide to dxz for the azide complex of hHO is shown to be consistent with the orbital hole determined by the azide π-plane in the latter complex, which is ∼90° in-plane rotated from that of the imidazole π-plane. The induction of the altered orbital ground state in the azide relative to the cyanide hHO complex, as well as the mean low-field bias of methyl hyperfine shifts and their paramagnetic relaxivity relative to those in globins, indicate that azide exerts a stronger ligand field in hHO than in the globins, or that the distal H-bonding to azide is weaker in hHO than in globins. The Asp140 → Ala hHO mutant that abolishes activity retains the unusual WT azide complex spin/orbital ground state. The relevance of our findings for other HO complexes and the HO mechanism is discussed. PMID:19243105

  9. The orbital ground state of the azide-substrate complex of human heme oxygenase is an indicator of distal H-bonding: implications for the enzyme mechanism.

    Science.gov (United States)

    Ogura, Hiroshi; Evans, John P; Peng, Dungeng; Satterlee, James D; Ortiz de Montellano, Paul R; La Mar, Gerd N

    2009-04-14

    The active site electronic structure of the azide complex of substrate-bound human heme oxygenase 1 (hHO) has been investigated by (1)H NMR spectroscopy to shed light on the orbital/spin ground state as an indicator of the unique distal pocket environment of the enzyme. Two-dimensional (1)H NMR assignments of the substrate and substrate-contact residue signals reveal a pattern of substrate methyl contact shifts that places the lone iron pi-spin in the d(xz) orbital, rather than the d(yz) orbital found in the cyanide complex. Comparison of iron spin relaxivity, magnetic anisotropy, and magnetic susceptibilities argues for a low-spin, (d(xy))(2)(d(yz),d(xz))(3), ground state in both azide and cyanide complexes. The switch from singly occupied d(yz) for the cyanide to d(xz) for the azide complex of hHO is shown to be consistent with the orbital hole determined by the azide pi-plane in the latter complex, which is approximately 90 degrees in-plane rotated from that of the imidazole pi-plane. The induction of the altered orbital ground state in the azide relative to the cyanide hHO complex, as well as the mean low-field bias of methyl hyperfine shifts and their paramagnetic relaxivity relative to those in globins, indicates that azide exerts a stronger ligand field in hHO than in the globins, or that the distal H-bonding to azide is weaker in hHO than in globins. The Asp140 --> Ala hHO mutant that abolishes activity retains the unusual WT azide complex spin/orbital ground state. The relevance of our findings for other HO complexes and the HO mechanism is discussed.

  10. Substrate water exchange for the oxygen evolving complex in PSII in the S1, S2, and S3 states.

    Science.gov (United States)

    Siegbahn, Per E M

    2013-06-26

    Detailed mechanisms for substrate water exchange in the oxygen evolving complex in photosystem II have been determined with DFT methods for large models. Existing interpretations of the experimental water exchange results have been quite different. By many groups, these results have been the main argument against the water oxidation mechanism suggested by DFT, in which the oxygen molecule is formed between a bridging oxo and an oxyl radical ligand in the center of the OEC. That mechanism is otherwise in line with most experiments. The problem has been that the mechanism requires a rather fast exchange of a bridging oxo ligand, which is not a common finding for smaller Mn-containing model systems. However, other groups have actually favored a substrate derived oxo ligand partly based on the same experiments. In the present study, three S-states have been studied, and the rates have been well reproduced by the calculations. The surprising experimental finding that water exchange in S1 is slower than the one in S2 is reproduced and explained. The key to this rate difference is the ease by which one of the manganese centers (Mn3) is reduced. This reduction has to occur to release the substrate water from Mn3. The similar rate of the slow exchange in S2 and S3 has been rationalized on the basis of earlier experiments combined with the present calculations. The results strongly support the previous DFT-suggested water oxidation mechanism.

  11. Activation of anaphase-promoting complex by p53 induces a state of dormancy in cancer cells against chemotherapeutic stress

    Science.gov (United States)

    Dai, Yafei; Wang, Lujuan; Tang, Jingqun; Cao, Pengfei; Luo, Zhaohui; Sun, Jun; Kiflu, Abraha; Sai, Buqing; Zhang, Meili; Wang, Fan; Li, Guiyuan; Xiang, Juanjuan

    2016-01-01

    Cancer dormancy is a stage in tumor progression in which residual disease remains occult and asymptomatic for a prolonged period. Cancer cell dormancy is the main cause of cancer recurrence and failure of therapy. However, cancer dormancy is poorly characterized and the mechanisms of how cancer cells develop dormancy and relapse remain elusive. In this study, 5- fluorouracil (5-FU) was used to induce cancer cell dormancy. We found that cancer cells escape the cytotoxicity of 5-FU by becoming “dormant”. After exposure to 5-FU, residual non-small cell lung cancer (NSCLC) cells underwent epithelial-mesenchymal transition (EMT), followed by mesenchymal-epithelial transition (MET). These EMT-transformed NSCLC cells were in the state of cell quiescence where cells were not dividing and were arrested in the cell cycle in G0-G1. The dormant cells underwent an EMT showed characteristics of cancer stem cells. P53 is strongly accumulated in response to 5-FU-induced dormant cells through the activation of ubiquitin ligase anaphase-promoting complex (APC/C) and TGF-β/Smad signaling. In contrast to the EMT-transformed cells, MET-transformed cells showed an increased ability to proliferate, suggesting that dormant EMT cells were reactivated in the MET process. During the EMT-MET process, DNA repair including nonhomologous end joining (NHEJ) and homologous recombination (HR) is critical to dormant cell reactivation. Our findings provide a mechanism to unravel cancer cell dormancy and reactivation of the cancer cell population. PMID:27009858

  12. Development of complex hydride-based all-solid-state lithium ion battery applying low melting point electrolyte

    Science.gov (United States)

    Suzuki, Shohei; Kawaji, Jun; Yoshida, Koji; Unemoto, Atsushi; Orimo, Shin-ichi

    2017-08-01

    A thermally durable all-solid-state lithium ion battery composed of a complex hydride, oxide electrolytes, and LiNi1/3Mn1/3Co1/3O2 active material is developed. This battery exhibits a discharge capacity of 56 mAh g-1, and the tenth capacity retention ratio is 29% at 150 °C owing to the large contact resistance between the electrolyte layer and the composite positive electrode layer. This large contact resistance is reduced by introducing an adhesive layer comprised of a mixture of LiBH4 and LiNH2 that is easily melted by thermal treatment and fills the voids and pores at the interface between the two layers. As a result, repeated charge-discharge cycles are successfully demonstrated at 150 °C with a high discharge capacity and discharge capacity retention ratio. The first discharge capacity is enhanced to 114 mAh g-1 and the capacity retention ratio at the tenth cycle is improved to 71%. These results demonstrate that using an adhesive layer is an effective measure to reduce the contact resistance and thereby enhance the performance of the battery.

  13. Production of Biomass-Degrading Multienzyme Complexes under Solid-State Fermentation of Soybean Meal Using a Bioreactor.

    Science.gov (United States)

    Vitcosque, Gabriela L; Fonseca, Rafael F; Rodríguez-Zúñiga, Ursula Fabiola; Bertucci Neto, Victor; Couri, Sonia; Farinas, Cristiane S

    2012-01-01

    Biomass-degrading enzymes are one of the most costly inputs affecting the economic viability of the biochemical route for biomass conversion into biofuels. This work evaluates the effects of operational conditions on biomass-degrading multienzyme production by a selected strain of Aspergillus niger. The fungus was cultivated under solid-state fermentation (SSF) of soybean meal, using an instrumented lab-scale bioreactor equipped with an on-line automated monitoring and control system. The effects of air flow rate, inlet air relative humidity, and initial substrate moisture content on multienzyme (FPase, endoglucanase, and xylanase) production were evaluated using a statistical design methodology. Highest production of FPase (0.55 IU/g), endoglucanase (35.1 IU/g), and xylanase (47.7 IU/g) was achieved using an initial substrate moisture content of 84%, an inlet air humidity of 70%, and a flow rate of 24 mL/min. The enzymatic complex was then used to hydrolyze a lignocellulosic biomass, releasing 4.4 g/L of glucose after 36 hours of saccharification of 50 g/L pretreated sugar cane bagasse. These results demonstrate the potential application of enzymes produced under SSF, thus contributing to generate the necessary technological advances to increase the efficiency of the use of biomass as a renewable energy source.

  14. Synthesis, spectral characterization, structures, and oxidation state distributions in [(corrolato)Fe(III)(NO)](n) (n = 0, +1, -1) complexes.

    Science.gov (United States)

    Sinha, Woormileela; Deibel, Naina; Agarwala, Hemlata; Garai, Antara; Schweinfurth, David; Purohit, Chandra Shekhar; Lahiri, Goutam Kumar; Sarkar, Biprajit; Kar, Sanjib

    2014-02-03

    Two novel trans-A2B-corroles and three [(corrolato){FeNO}(6)] complexes have been prepared and characterized by various spectroscopic techniques. In the native state, all these [(corrolato){FeNO}(6)] species are diamagnetic and display "normal" chemical shifts in the (1)H NMR spectra. For two of the structurally characterized [(corrolato){FeNO}(6)] derivatives, the Fe-N-O bond angles are 175.0(4)° and 171.70(3)° (DFT: 179.94°), respectively, and are designated as linear nitrosyls. The Fe-N (NO) bond distances are 1.656(4) Å and 1.650(3) Å (DFT: 1.597 Å), which point toward a significant Fe(III) → NO back bonding. The NO bond lengths are 1.159(5) Å and 1.162(3) Å (DFT: 1.162 Å) and depict their elongated character. These structural data are typical for low-spin Fe(III). Electrochemical measurements show the presence of a one-electron oxidation and a one-electron reduction process for all the complexes. The one-electron oxidized species of a representative [(corrolato){FeNO}(6)] complex exhibits ligand to ligand charge transfer (LLCT) transitions (cor(π) → cor(π*)) at 399 and 637 nm, and the one-electron reduced species shows metal to ligand charge transfer (MLCT) transition (Fe(dπ) → cor(π*)) in the UV region at 330 nm. The shift of the νNO stretching frequency of a representative [(corrolato){FeNO}(6)] complex on one-electron oxidation occurs from 1782 cm(-1) to 1820 cm(-1), which corresponds to 38 cm(-1), and on one-electron reduction occurs from 1782 cm(-1) to 1605 cm(-1), which corresponds to 177 cm(-1). The X-band electron paramagnetic resonance (EPR) spectrum of one-electron oxidation at 295 K in CH2Cl2/0.1 M Bu4NPF6 displays an isotropic signal centered at g = 2.005 with a peak-to-peak separation of about 15 G. The in situ generated one-electron reduced species in CH2Cl2/0.1 M Bu4NPF6 at 295 K shows an isotropic signal centered at g = 2.029. The 99% contribution of corrole to the HOMO of native species indicates that oxidation occurs from

  15. Chemical physics behind formation of efficient charge-separated state for complexation between PC70BM and designed diporphyrin in solution.

    Science.gov (United States)

    Ray, Anamika; Banerjee, Shrabanti; Ghosh, Shalini; Bauri, Ajoy K; Bhattacharya, Sumanta

    2016-01-05

    The present work reports supramolecular interaction of [6,6]-phenyl C71 butyric acid methyl ester (PC70BM) with two designed diporphyrin molecules having dithiophene (1) and carbazole (2) spacer in solvent having varying polarity. Studies on complex formation reveal relatively higher binding constant for PC70BM/2 complex in all the solvent studied. Solvent dependence of charge separation and charge recombination processes in PC70BM/diporphyrin non-covalent complexes has been well established in present work. Donor-acceptor geometry and stabilization of the singlet excited state of the diporphyrin during charge recombination are considered to be the possible reasons for this behavior.

  16. Density functional theory calculations on the complexation of p-arsanilic acid with hydrated iron oxide clusters: structures, reaction energies, and transition states.

    Science.gov (United States)

    Adamescu, Adrian; Hamilton, Ian P; Al-Abadleh, Hind A

    2014-07-31

    Aromatic organoarsenicals, such as p-arsanilic acid (pAsA), are still used today as feed additives in the poultry and swine industries in developing countries. Through the application of contaminated litter as a fertilizer, these compounds enter the environment and interact with reactive soil components such as iron and aluminum oxides. Little is known about these surface interactions at the molecular level. We report density functional theory (DFT) calculations on the energies, optimal geometries, and vibrational frequencies for hydrated pAsA/iron oxide complexes, as well as changes in Gibbs free energy, enthalpy, and entropy for various types of ligand exchange reactions leading to both inner- and outer-sphere complexes. Similar calculations using arsenate are also shown for comparison, along with activation barriers and transition state geometries between inner-sphere complexes. Minimum energy calculations show that the formation of inner- and outer-sphere pAsA/iron oxide complexes is thermodynamically favorable, with the monodentate mononuclear complexes being the most favorable. Interatomic As-Fe distances are calculated to be between 3.3 and 3.5 Å for inner-sphere complexes and between 5.2 and 5.6 Å for outer-sphere complexes. In addition, transition state calculations show that activation energies greater than 23 kJ/mol are required to form the bidentate binuclear pAsA/iron oxide complexes, and that formation of arsenate bidentate binuclear complexes is thermodynamically -rather than kinetically- driven. Desorption thermodynamics using phosphate ions show that reactions are most favorable using HPO4(2-) species. The significance of our results for the overall surface complexation mechanism of pAsA and arsenate is discussed.

  17. Effect of Rasbha spin-orbit interaction on the ground state energy of a hydrogenic D{sup 0} complex in a Gaussian quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Boda, Aalu, E-mail: aaluphd@gmail.com; Kumar, D. Sanjeev; Chatterjee, Ashok [School of Physics, University of Hyderabad, Hyderabad-500046, Telangana (India); Mukhopadhyay, Soma [Department of Physics, DVR College of Engineering and Technology, Sangareddy Mandal, Hyderabad 502285 (India)

    2015-06-24

    The ground state energy of a hydrogenic D{sup 0} complex trapped in a three-dimensional GaAs quantum dot with Gaussian confinement is calculated variationally incorporating the effect of Rashba spin-orbit interaction. The results are obtained as a function of the quantum dot size and the Rashba spin-orbit interaction. The results show that the Rashba interaction reduces the ground state energy of the system.

  18. Solid-state thermolysis of a fac-rhenium(I) carbonyl complex with a redox non-innocent pincer ligand.

    Science.gov (United States)

    Jurca, Titel; Chen, Wen-Ching; Michel, Sheila; Korobkov, Ilia; Ong, Tiow-Gan; Richeson, Darrin S

    2013-03-25

    The development of rhenium(I) chemistry has been restricted by the limited structural and electronic variability of the common pseudo-octahedral products fac-[ReX(CO)3L2] (L2 = α-diimine). We address this constraint by first preparing the bidentate bis(imino)pyridine complexes [(2,6-{2,6-Me2C6H3N=CPh}2C5H3N)Re(CO)3X] (X = Cl 2, Br 3), which were characterized by spectroscopic and X-ray crystallographic means, and then converting these species into tridentate pincer ligand compounds, [(2,6-{2,6-Me2C6H3N=CPh}2C5H3N)Re(CO)2X] (X = Cl 4, Br 5). This transformation was performed in the solid-state by controlled heating of 2 or 3 above 200 °C in a tube furnace under a flow of nitrogen gas, giving excellent yields (≥95 %). Compounds 4 and 5 define a new coordination environment for rhenium(I) carbonyl chemistry where the metal center is supported by a planar, tridentate pincer-coordinated bis(imino)pyridine ligand. The basic photophysical features of these compounds show significant elaboration in both number and intensity of the d-π* transitions observed in the UV/Vis spec tra relative to the bidentate starting materials, and these spectra were analyzed using time-dependent DFT computations. The redox nature of the bis(imino)pyridine ligand in compounds 2 and 4 was examined by electrochemical analysis, which showed two ligand reduction events and demonstrated that the ligand reduction shifts to a more positive potential when going from bidentate 2 to tridentate 4 (+160 mV for the first reduction step and +90 mV for the second). These observations indicate an increase in electrostatic stabilization of the reduced ligand in the tridentate conformation. Elaboration on this synthetic methodology documented its generality through the preparation of the pseudo-octahedral rhenium(I) triflate complex [(2,6-{2,6-Me2C6H3N=CPh}2C5H3N)Re(CO)2OTf] (7, 93 % yield). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Synthesis, spectroscopic characterization, solid state d.c. electrical conductivity and biological studies of some lanthanide(III chloride complexes with a heterocyclic Schiff base ligand

    Directory of Open Access Journals (Sweden)

    K. Mohanan

    2016-07-01

    Full Text Available Condensation of 2-hydroxy-1-naphthaldehyde with 2-amino-3-carboxyethyl-4,5-dimethylthiophene in 1:1 molar ratio, yielded a potentially tridentate Schiff base viz. 2-[N-(2′-hydroxy-1-naphthylideneamino]-3-carboxyethyl-4,5-dimethylthiophene (HNAT. This ligand formed complexes with lanthanum(III, cerium(III, praseodymium(III, neodymium(III, samarium(III, europium(III and gadolinium(III chloride under well defined conditions. These complexes were characterized through elemental analysis, molar conductance, magnetic moment measurements, IR, UV–Vis, FAB mass and 1H NMR spectral studies. Analytical data showed that all the metal complexes exhibited 1:1 metal–ligand ratio. Molar conductance values adequately confirmed the non-electrolytic nature of the metal complexes. The proton NMR spectral observations supplement the IR spectral assignments. The spectral data revealed that the ligand acted as neutral tridentate, coordinating to the metal ion through azomethine nitrogen, ester carbonyl and naphtholate oxygen without deprotonation. The ligand and its lanthanum(III chloride complex were subjected to XRD studies. The lanthanum(III chloride complex has undergone a facile transesterification reaction. The solid state d.c. electrical conductivity of some selected complexes were measured as a function of temperature, indicating the semiconducting nature of the metal complexes. The antimicrobial activities were examined by disk diffusion method against some pathogenic bacterial and fungal species.

  20. Photosystem I light-harvesting complex Lhca4 adopts multiple conformations : Red forms and excited-state quenching are mutually exclusive

    NARCIS (Netherlands)

    Passarini, Francesca; Wientjes, Emilie; van Amerongen, Herbert; Croce, Roberta

    2010-01-01

    In this work we have investigated the origin of the multi-exponential fluorescence decay and of the short excited-state lifetime of Lhca4. Lhca4 is the antenna complex of Photosystem I which accommodates the red-most chlorophyll forms and it has been proposed that these chlorophylls can play a role

  1. Photosystem I light-harvesting complex Lhca4 adopts multiple conformations: red forms and excited-state quenching are mutually exclusive

    NARCIS (Netherlands)

    Passarini, F.; Wientjes, E.; Amerongen, van H.; Croce, R.

    2010-01-01

    In this work we have investigated the origin of the multi-exponential fluorescence decay and of the short excited-state lifetime of Lhca4. Lhca4 is the antenna complex of Photosystem I which accommodates the red-most chlorophyll forms and it has been proposed that these chlorophylls can play a role

  2. The effects of detergents DDM and β-OG on the singlet excited state lifetime of the chlorophyll a in cytochrome b6f complex from spinach chloroplasts

    Institute of Scientific and Technical Information of China (English)

    CHEN XiaoBo; ZHAO XiaoHui; ZHANG JianPing; LI LiangBi; KUANG TingYun

    2007-01-01

    The singlet excited state lifetime of the chlorophyll a (Chi a) in cytochrome b6f (Cyt b6f) complex was reported to be shorter than that of free Chl a in methanol, but the value was different for Cyt b6f complexes from different sources (~200 and ~600 ps are the two measured results). The present study demonstrated that the singiet excited state lifetime is associated with the detergents n-dodecyl-β-D-maltoside (DDM) and n-octyl-β-D-glucopyranoside (β-OG), but has nothing to do with the different sources of Cyt b6f complexes. Compared with the Cyt b6f dissolved in β-OG, the Cyt b6f in DDM had a lower fluorescence yield, a lower photodegradation rate of Chl a, and a shorter lifetime of Chl a excited state. In short, the singlet excited state lifetime, ~200 ps, of the Chl a in Cyt b6f complex in DDM is closer to the true in vivo.

  3. The effects of detergents DDM and β-OG on the singlet excited state lifetime of the chlorophyll a in cytochrome b6f complex from spinach chloroplasts

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The singlet excited state lifetime of the chlorophyll a (Chl a) in cytochrome b6f (Cyt b6f) complex was reported to be shorter than that of free Chl a in methanol, but the value was different for Cyt b6f com-plexes from different sources (~200 and ~600 ps are the two measured results). The present study demonstrated that the singlet excited state lifetime is associated with the detergents n-dodecyl-β-D- maltoside (DDM) and n-octyl-β-D-glucopyranoside (β-OG), but has nothing to do with the different sources of Cyt b6f complexes. Compared with the Cyt b6f dissolved in β-OG, the Cyt b6f in DDM had a lower fluorescence yield, a lower photodegradation rate of Chl a, and a shorter lifetime of Chl a excited state. In short, the singlet excited state lifetime, ~200 ps, of the Chl a in Cyt b6f complex in DDM is closer to the true in vivo.

  4. The "Reading the Mind in Films" Task [Child Version]: Complex Emotion and Mental State Recognition in Children with and without Autism Spectrum Conditions

    Science.gov (United States)

    Golan, Ofer; Baron-Cohen, Simon; Golan, Yael

    2008-01-01

    Children with autism spectrum conditions (ASC) have difficulties recognizing others' emotions. Research has mostly focused on "basic" emotion recognition, devoid of context. This study reports the results of a new task, assessing recognition of "complex" emotions and mental states in social contexts. An ASC group (n = 23) was compared to a general…

  5. The Complex Life Experience of First-Generation College Students Who Are Working Adults in the Appalachian Region of the United States: A Phenomenological Study

    Science.gov (United States)

    Thurman, Deborah Elizabeth

    2016-01-01

    The purpose of this transcendental phenomenological study was to describe and understand the complexity of life experiences for first-generation college students or recent graduates who are working adults in the Central and South-Central Appalachian region of the United States in light of the construct resilience and how purposefully selected…

  6. Resonant X-ray emission spectroscopy reveals d-d ligand-field states involved in the self-assembly of a square-planar platinum complex.

    Science.gov (United States)

    Garino, Claudio; Gallo, Erik; Smolentsev, Nikolay; Glatzel, Pieter; Gobetto, Roberto; Lamberti, Carlo; Sadler, Peter J; Salassa, Luca

    2012-11-28

    Resonant X-ray Emission Spectroscopy (RXES) is used to characterize the ligand field states of the prototypic self-assembled square-planar complex, [Pt(tpy)Cl]Cl (tpy=2,2':6',2''-terpyridine), and determine the effect of weak metal-metal and π-π interactions on their energy.

  7. Excited state intramolecular proton transfer (ESIPT) in six-coordinated zinc(ii)-quinoxaline complexes with ligand hydrogen bonds: their fluorescent properties sensitive to axial positions.

    Science.gov (United States)

    Sakai, Ken-Ichi; Takahashi, Sami; Kobayashi, Ataru; Akutagawa, Tomoyuki; Nakamura, Takayoshi; Dosen, Masaaki; Kato, Masako; Nagashima, Umpei

    2010-02-28

    Zinc(ii)-quinoxaline complexes, [Zn(hqxc)(2)(py)(2)] and [Zn(hqxc)(2)(DMSO)(2)] (hqxc = 3-hydroxy-2-quinoxalinecarboxylate, py = pyridine, DMSO = dimethyl sulfoxide), were prepared and characterized by X-ray crystallography and fluorescence spectroscopy. In both complexes, the zinc ion is six-coordinated by two equatorial bidentate hqxc ligands with an intramolecular hydrogen bond and two axial monodentate ligands such as pyridine or DMSO. In spite of similar coordination geometries, there is a remarkable difference between their solid-state fluorescent properties. The pyridine complex is strongly fluorescent (fluorescence quantum yield Phi = 0.22), giving rise to a significantly Stokes-shifted spectrum. From its thin film photopumped by a nitrogen gas laser, amplified spontaneous emission was observed. These results suggest that the fluorescence occurs by way of excited-state intramolecular proton-transfer (ESIPT) in the hydrogen bond of hqxc. On the other hand, the DMSO complex shows fluorescent intensity (Phi = 0.08) lower than that of the pyridine complex, and shows normal emission in addition to ESIPT emission. From IR measurements for these complexes, it is concluded that axial ligands influence the hydrogen bond strength of the equatorial hqxc ligand via zinc and thus the ESIPT efficiency.

  8. Exploring excited-state tunability in luminescent tris-cyclometalated platinum(IV) complexes: synthesis of heteroleptic derivatives and computational calculations.

    Science.gov (United States)

    Juliá, Fabio; Aullón, Gabriel; Bautista, Delia; González-Herrero, Pablo

    2014-12-22

    The synthesis, structure, electrochemistry, and photophysical properties of a series of heteroleptic tris- cyclometalated Pt(IV) complexes are reported. The complexes mer-[Pt(C^N)2 (C'^N')]OTf, with C^N=C-deprotonated 2-(2,4-difluorophenyl)pyridine (dfppy) or 2-phenylpyridine (ppy), and C'^N'=C-deprotonated 2-(2-thienyl)pyridine (thpy) or 1-phenylisoquinoline (piq), were obtained by reacting bis- cyclometalated precursors [Pt(C^N)2 Cl2] with AgOTf (2 equiv) and an excess of the N'^C'H pro-ligand. The complex mer-[Pt(dfppy)2 (ppy)]OTf was obtained analogously and photoisomerized to its fac counterpart. The new complexes display long-lived luminescence at room temperature in the blue to orange color range. The emitting states involve electronic transitions almost exclusively localized on the ligand with the lowest π-π* energy gap and have very little metal character. DFT and time-dependent DFT (TD-DFT) calculations on mer-[Pt(ppy)2 (C'^N')](+) (C'^N'=thpy, piq) and mer/fac-[Pt(ppy)3](+) support this assignment and provide a basis for the understanding of the luminescence of tris-cyclometalated Pt(IV) complexes. Excited states of LMCT character may become thermally accessible from the emitting state in the mer isomers containing dfppy or ppy as chromophoric ligands, leading to strong nonradiative deactivation. This effect does not operate in the fac isomers or the mer complexes containing thpy or piq, for which nonradiative deactivation originates mainly from vibrational coupling to the ground state. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. The performance of nonhybrid density functionals for calculating the structures and spin states of Fe(II) and Fe(III) complexes.

    Science.gov (United States)

    Deeth, Robert J; Fey, Natalie

    2004-11-30

    The local density approximation and a range of nonhybrid gradient corrected density functionals (PW91, BLYP, PBE, revPBE, RPBE) have been assessed with respect to the prediction of geometries and spin-state energy preferences for a range of homoleptic Fe(II)L6 and Fe(III)L6 complexes, where L = Cl-, CN-, NH3, pyridine, imidazole, H2O, O=CH2 and tetrahydrofuran. While the qualitative spin-state energies from in vacuo structure optimizations are reasonable the geometries are relatively poorly treated, especially for [FeCl6]3-/4-. Structural results for all the complexes are significantly improved by including environmental effects. The best compromise between structural and spin-state predictive accuracy was obtained for the RPBE functional in combination with the COSMO solvation approach. This approach systematically overestimates the energetic preference for a low spin state, which is partly due to the well-known effect of the lack of exact exchange in nonhybrid functionals and partly due to the larger solvation stabilization of low-spin complexes that have shorter bond lengths and thus smaller molecular volumes than their high-spin partners. Calculations on low spin [Fe(bipy)3]2+ and [Fe(phen)3]2+ and their ortho methyl substituted analogs, which are high spin at room temperature but cross over to low spin at low temperature, suggest the RPBE/COSMO combination generates low spin states which are too stable by approximately 13 kcal mol(-1).

  10. Parasites of Psittaciformes and Accipitriformes in Paraíba state, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Cristiane Maria Fernandes de Melo

    Full Text Available In this study, we investigated the presence of gastrointestinal helminths in 97 captive birds (Psittaciformes and Accipitriformes necropsied between June and December 2011 in the state of Paraiba, Brazil. Forty-three birds were infected. Psittaciformes were infected by nematode Ascaridia hermaphrodita (97.6% and cestodeRaillietina sp. (2.4%. A. hermaphrodita was found in all species of parrots andRaillietina sp. was found only in Amazona aestiva. A. hermaphrodita was the cause of death, by intestinal obstruction, in 14 of the 40 birds investigated. Accipitriformes were infected by nematode Synhimantus(Synhimantus rectus (100% and acantocephalan Centrorhynchus tumidulus (50%. In Brazil, Diopsittaca nobilis and A. aestiva are reported for the first time as hosts of A. hermaphrodita andRaillietina sp., respectively. We concluded that Psittaciformes and Accipitriformes in captivity are affected by nematodes, cestodes and acanthocephalans and that implementation of control measures is essential.

  11. Solid-state characterization and in vitro dissolution behavior of lorazepam: Hydroxypropyl-β-cyclodextrin inclusion complex.

    Science.gov (United States)

    Patel, R; Patel, M

    2010-12-01

    The objectives of this research were to prepare and characterize inclusion complexes of lorazepam with hydroxypropyl-β-cyclodextrin and to study the effect of complexation on the dissolution rate of lorazepam, a water-insoluble drug. The phase solubility profile of lorazepam with hydroxypropyl-β-cyclodextrin was an AP-type, indicating the formation of 2:1 stoichiometric inclusion complexes. Gibbs free energy values were all negative, indicating the spontaneous nature of lorazepam solubilization, and they decreased with an increase in the cyclodextrin concentration, demonstrating that the reaction conditions became more favorable as the concentration of cyclodextrins increased. Complexes of lorazepam were prepared with cyclodextrin using various methods such as physical mixing, kneading, spray-drying, and lyophilization. The complexes were characterized by differential scanning calorimetry, Fourier-transform infrared, scanning electron microscopy, and powder X-ray diffraction studies. These studies indicated that a complex prepared by lyophilization had successful inclusion of the lorazepam molecule into the cyclodextrin cavity. Complexation resulted in a marked improvement in the solubility and wettability of lorazepam. Among all the samples, a complex prepared with hydroxypropyl-β-cyclodextrin by lyophilization had the greatest improvement in the in vitro rate of lorazepam dissolution. The mean dissolution time for lorazepam decreased significantly after preparing complexes and physical mixtures of lorazepam with cyclodextrin. The similarity factor indicated a significant difference between the release profiles of lorazepam from complexes and physical mixtures and from plain lorazepam. Tablets containing complexes prepared with cyclodextrins had significant improvement in the release profile of lorazepam as compared to tablets containing lorazepam without cyclodextrin.

  12. Gas-phase doubly charged complexes of cyclic peptides with copper in +1, +2 and +3 formal oxidation states: formation, structures and electron capture dissociation.

    Science.gov (United States)

    Afonso, Carlos; Tabet, Jean-Claude; Giorgi, Gianluca; Tureček, František

    2012-02-01

    Copper complexes with a cyclic D-His-β-Ala-L-His-L-Lys and all-L-His-β-Ala-His-Lys peptides were generated by electrospray which were doubly charged ions that had different formal oxidation states of Cu(I), Cu(II) and Cu(III) and different protonation states of the peptide ligands. Electron capture dissociation showed no substantial differences between the D-His and L-His complexes. All complexes underwent peptide cross-ring cleavages upon electron capture. The modes of ring cleavage depended on the formal oxidation state of the Cu ion and peptide protonation. Density functional theory (DFT) calculations, using the B3LYP with an effective core potential at Cu and M06-2X functionals, identified several precursor ion structures in which the Cu ion was threecoordinated to pentacoordinated by the His and Lys side-chain groups and the peptide amide or enolimine groups. The electronic structure of the formally Cu(III) complexes pointed to an effective Cu(I) oxidation state with the other charge residing in the peptide ligand. The relative energies of isomeric complexes of the [Cu(c-HAHK + H)](2+) and [Cu(c-HAHK - H)](2+) type with closed electronic shells followed similar orders when treated by the B3LYP and M06-2X functionals. Large differences between relative energies calculated by these methods were obtained for open-shell complexes of the [Cu(c-HAHK)](2+) type. Charge reduction resulted in lowering the coordination numbers for some Cu complexes that depended on the singlet or triplet spin state being formed. For [Cu(c-HAHK - H)](2+) complexes, solution H/D exchange involved only the N-H protons, resulting in the exchange of up to seven protons, as established by ultra-high mass resolution measurements. Contrasting the experiments, DFT calculations found the lowest energy structures for the gas-phase ions that were deprotonated at the peptide C(α) positions.

  13. Changes in magnetic properties from solid state to solution in a trinuclear linear copper(II) complex

    NARCIS (Netherlands)

    Koval, I.A.; Akhideno, H.; Tanase, S.; Belle, C.; Duboc, C.; Saint-Aman, E.; Gamez, P.; Tooke, D.M.; Spek, A.L.; Pierre, J.-L.; Reedijk, J.

    2007-01-01

    A linear trinuclear copper(II) complex containing phenoxido- and alkoxido-bridges between the metal centers has been isolated and structurally characterized. The complex cation consists of a linear array of three copper ions, assembled by means of two doubly deprotonated ligands. The octahedral coor

  14. Crescimento e bromatologia do feijão-bravo (Capparis flexuosa L.) em área de Caatinga no Curimataú paraibano, Brasil Growth and bromatology of Capparis flexuosa at Curimatau region, Paraiba state, Brazil

    National Research Council Canada - National Science Library

    Jorge Xavier de Almeida Neto; Albericio Pereira de Andrade; Alecksandra Vieira de Lacerda; Leonardo Pessoa Félix; Divan Soares da Silva

    2011-01-01

    Este trabalho teve como objetivo caracterizar aspectos relacionados com o crescimento e a bromatologia do feijão-bravo (Capparis flexuosa L.) em uma área no Curimataú, Semiárido Paraibano. Para a análise da...

  15. Mitochondrial bioenergetics and redox state are unaltered in Trypanosoma cruzi isolates with compromised mitochondrial complex I subunit genes.

    Science.gov (United States)

    Carranza, Julio César; Kowaltowski, Alicia J; Mendonça, Marco Aurélio G; de Oliveira, Thays C; Gadelha, Fernanda R; Zingales, Bianca

    2009-06-01

    In trypanosomatids the involvement of mitochondrial complex I in NADH oxidation has long been debated. Here, we took advantage of natural Trypanosoma cruzi mutants which present conspicuous deletions in ND4, ND5 and ND7 genes coding for complex I subunits to further investigate its functionality. Mitochondrial bioenergetics of wild type and complex I mutants showed no significant differences in oxygen consumption or respiratory control ratios in the presence of NADH-linked substrates or FADH(2)-generating succinate. No correlation could be established between mitochondrial membrane potentials and ND deletions. Since release of reactive oxygen species occurs at complex I, we measured mitochondrial H(2)O(2) formation induced by different substrates. Significant differences not associated to ND deletions were observed among the parasite isolates, demonstrating that these mutations are not important for the control of oxidant production. Our data support the notion that complex I has a limited function in T. cruzi.

  16. Chronic Intermittent Hypoxia Differentially Impacts Different States of Inspiratory Activity at the Level of the preBötzinger Complex

    Directory of Open Access Journals (Sweden)

    Alfredo J. Garcia

    2017-08-01

    Full Text Available The preBötzinger complex (preBötC is a medullary brainstem network crucially involved in the generation of different inspiratory rhythms. In the isolated brainstem slice, the preBötC reconfigures to produce different rhythms that we refer to as “fictive eupnea” under baseline conditions (i.e., carbogen, and “fictive gasping” in hypoxia. We recently demonstrated that fictive eupnea is irregular following exposure to chronic intermittent hypoxia (CIH. However, it is unknown how CIH impacts fictive gasping. To address this, brain slices containing the preBötC were prepared from control and CIH exposed mice. Electrophysiological recordings of rhythmogenesis were obtained during the perihypoxic interval. We examined how CIH affects various dynamic aspects of the rhythm characterized by: (1 the irregularity score (IrS, to assess burst-to-variability; (2 the fluctuation value (χ, to quantify the gain of oscillations throughout the time series; and (3 Sample Entropy (sENT, to characterize the pattern/structure of oscillations in the time series. In baseline conditions, CIH increased IrS of amplitude (0.21 ± 0.2 and χ of amplitude (0.34 ± 0.02 but did not affect sENT of amplitude. This indicated that CIH increased burst-to-burst irregularity and the gain of amplitude fluctuations but did not affect the overall pattern/structure of amplitude oscillations. During the transition to hypoxia, 33% of control rhythms whereas 64% of CIH-exposed rhythms showed no doubling of period, suggesting that the probability for stable rhythmogenesis during the transition to hypoxia was greater following CIH. While 29% of control rhythms maintained rhythmicity throughout hypoxia, all slices from CIH exposed mice exhibited rhythms throughout the hypoxic interval. During hypoxia, differences in χ for amplitude were no longer observed between groups. To test the contribution of the persistent sodium current, we examined how riluzole influenced rhythmogenesis

  17. Preparation, physicochemical analysis and molecular modeling investigation of 2,2‧-Bipyridine: β-Cyclodextrin inclusion complex in solution and solid state

    Science.gov (United States)

    Periasamy, R.; Kothainayaki, S.; Sivakumar, K.

    2015-11-01

    Supramolecular interaction between 2,2‧-Bipyridine (BPY) and β-Cyclodextrin (β-CD) has been investigated in solution and solid state. Non-covalent interaction between BPY and β-CD was studied in solution using absorption and fluorescence spectroscopy. Inclusion complex of BPY and β-CD was prepared in solid state by co-precipitation method and it was characterized using Fourier Transform Infra-red spectroscopy (FT-IR), Thermal analysis, Scanning Electron Microscopy (SEM), Powder X-ray diffractometry (XRD) and Atomic Force Microscopy (AFM). Binding constant values and 1:1 stoichiometry of the inclusion complex were calculated using Benesi-Hildebrand plots at 303 K. Using continuous variation method the 1:1 stoichiometry has been confirmed for BPY: β-CD complex. Thermodynamic parameter, ΔG of inclusion complex formation was determined and the negative value indicated that the inclusion process was an exergonic and spontaneous process. The most probable model of BPY: β-CD inclusion complex suggested by molecular docking studies was in good agreement with the results obtained by experimental methods.

  18. Numerical Simulation of Unsteady-State Flow in Dual Porous Coalbed Methane Horizontal Wells with Complex Boundary Conditions

    Directory of Open Access Journals (Sweden)

    Cheng-yong Li

    2015-01-01

    Full Text Available The bottom-hole pressure response which can reflect the gas flow characteristics is important to study. A mathematical model for description of gas from porous coalbed methane (CBM reservoirs with complex boundary conditions flowing into horizontal wells has been developed. Meanwhile, basic solution of boundary elements has been acquired by combination of Lord Kelvin point source solution, the integral of Bessel function, and Poisson superimpose formula for CBM horizontal wells with complex boundary conditions. Using this model, type curves of dimensionless pressure and pressure derivative are obtained, and flow characteristics of horizontal wells in complex boundary reservoirs and relevant factors are accordingly analyzed.

  19. Hydrido-ruthenium cluster complexes as models for reactive surface hydrogen species of ruthenium nanoparticles. Solid-state 2H NMR and quantum chemical calculations.

    Science.gov (United States)

    Gutmann, Torsten; Walaszek, Bernadeta; Yeping, Xu; Wächtler, Maria; del Rosal, Iker; Grünberg, Anna; Poteau, Romuald; Axet, Rosa; Lavigne, Guy; Chaudret, Bruno; Limbach, Hans-Heinrich; Buntkowsky, Gerd

    2010-08-25

    The (2)H quadrupolar interaction is a sensitive tool for the characterization of deuterium-metal binding states. In the present study, experimental solid-state (2)H MAS NMR techniques are used in the investigations of two ruthenium clusters, D(4)Ru(4)(CO)(12) (1) and D(2)Ru(6)(CO)(18) (2), which serve as model compounds for typical two-fold, three-fold, and octahedral coordination sites on metal surfaces. By line-shape analysis of the (2)H MAS NMR measurements of sample 1, a quadrupolar coupling constant of 67 +/- 1 kHz, an asymmetry parameter of 0.67 +/- 0.1, and an isotropic chemical shift of -17.4 ppm are obtained. In addition to the neutral complex, sample 2 includes two ionic clusters, identified as anionic [DRu(6)(CO)(18)](-) (2(-)) and cationic [D(3)Ru(6)(CO)(18)](+) (2(+)). By virtue of the very weak quadrupolar interaction (Quantum chemical DFT calculations at different model structures for these ruthenium clusters were arranged in order to help in the interpretation of the experimental results. It is shown that the (2)H nuclear quadrupolar interaction is a sensitive tool for distinguishing the binding state of the deuterons to the transition metal. Combining the data from the polynuclear complexes with the data from mononuclear complexes, a molecular ruler for quadrupolar interactions is created. This ruler now permits the solid-state NMR spectroscopic characterization of deuterium adsorbed on the surfaces of catalytically active metal nanoparticles.

  20. Simplifying complexity

    NARCIS (Netherlands)

    Leemput, van de I.A.

    2016-01-01

    In this thesis I use mathematical models to explore the properties of complex systems ranging from microbial nitrogen pathways and coral reefs to the human state of mind. All are examples of complex systems, defined as systems composed of a number of interconnected parts, where the systemic behavior

  1. Syntheses and solid state structures of zinc (II) complexes with Bi-dentate -(Aryl)imino-acenapthenone (Ar-BIAO) ligands

    Indian Academy of Sciences (India)

    Srinivas Anga; Supriya Rej; Kishor Naktode; Tigmansu Pal; Tarun K Panda

    2015-01-01

    We have synthesized five zinc complexes of molecular formulae [ZnCl2(2,6-dimethylphenyl-BIAO)]2 (1a), [ZnBr2(2,6-dimethylphenyl-BIAO)]2 (1b), [ZnI2(2,6-dimethylphenyl-BIAO)]2(1c), [ZnBr2(mes-BIAO)]2(2b) and [ZnBr2(dipp-BIAO)] (3b) with rigid unsymmetrical iminoacenaphthenone ligands, (2,6-dimethylphenyl-BIAO) (1), (mesityl-BIAO) (2) and (2,6-diisopropylphenyl-BIAO) (3). The zinc complex 1a was prepared by the reaction of ZnCl2 and neutral (mesityl-BIAO) (1). However, complexes 1b, 2b and 3b were obtained by the treatment of ZnBr2 and neutral ligands 1-3 respectively in 1:1 molar ratio in dichloromethane at ambient temperature. In a similar reaction of ZnI2 with (2,6-dimethylphenyl-BIAO) (1) in dichloromethane the corresponding iodo-complex 1c was obtained in good yield. All the zinc (II) complexes are characterized by FT-IR, 1H and 13C{1H} NMR spectroscopic techniques. The solid state structures of the complexes 1a, 1b, 1c, 2b and 3b are confirmed by single crystal X-ray diffraction analysis. The molecular structures of complexes 1a, 1b, 1c and 2b reveal the dimeric nature of the complexes and subsequently the centre atom zinc is penta-coordinated to adopt distorted trigonal bipyramidal geometry around it. In contrast, the complex 3b is in monomeric in nature due to bulkier size of the ligand and zinc ion is tetra coordinated to adopt distorted tetrahedral geometry.

  2. Critical assessment of electron spin resonance studies on Cu(I)-NO complexes in Cu-ZSM-5 zeolites prepared by solid- and liquid-state ion exchange.

    Science.gov (United States)

    Umamaheswari, V; Hartmann, Martin; Pöppl, Andreas

    2005-10-27

    Cu(I)-NO adsorption complexes were formed over Cu-ZSM-5 zeolites prepared by (i) solid-state ion exchange of NH(4)-ZSM-5 with CuCl and (ii) liquid-state ion exchange of ZSM-5 with Cu(CH(3)COO)(2). Electron spin resonance spectroscopy revealed the formation of two different Cu(I)-NO species A and B in both systems, whose spin Hamiltonian parameters are comparable with those already reported for the Cu(I)-NO species formed over 66% Cu(II) liquid-state ion-exchanged Cu-ZSM-5 materials. The population of the species A and B differs for the two systems studied. Formation of species B is more favored in the solid-state ion-exchanged Cu-ZSM-5 when compared to the liquid-state exchanged zeolite. The X-, Q- and W-band electron spin resonance spectra recorded at 6 and 77 K reveal the presence of a rigid geometry of the adsorption complexes at 6 K and a dynamic complex structure at higher temperatures such as 77 K. This is indicated by the change in the spin Hamiltonian parameters of the formed Cu(I)-NO species in both the liquid- and solid-state ion-exchanged Cu-ZSM-5 zeolites from 6 to 77 K. Possible models for the motional effects found at elevated temperatures are discussed. The temperature dependence of the electron spin phase memory time measured by two-pulse electron spin-echo experiments indicates, likewise, the onset of a motional process of the adsorbed NO molecules at temperatures above 10 K. The studies support previous assignments where the NO complexes are formed at two different Cu(I) cationic sites in the ZSM-5 framework and highlight that multifrequency electron spin resonance experiments at low temperatures are essential for reliable determination of the spin Hamiltonian parameters of the formed adsorption complexes for further comparison with Cu(I)-NO complex structures predicted by quantum chemical calculations.

  3. Semiconduction properties of some polyene-iodine charge-transfer complexes and their application in solid-state batteries

    Energy Technology Data Exchange (ETDEWEB)

    Sen, S.; Pal, P.; Misra, T.N. (Indian Association for the Cultivation of Science, Calcutta (India). Dept. of Spectroscopy)

    1993-03-01

    The conjugated polyenes [beta]-carotene, lutein, retinoic acid and [beta]-apo-8'-carotenal are shown to form charge-transfer (CT) complexes with the electron acceptor iodine. The conductivity increases by several orders of magnitude and the activation energy decreases on CT complex formation. Using these complexes as cathodic material, batteries with the configuration Mg/(polyene-iodine CT complex)/graphite are developed. Different battery parameters are evaluated. The effects of ambient temperature and humidity on battery performance are also studied. Results show that a [beta]-apo-8'-carotenal-1[sub 2] based battery has the maximum power density and longest self-life and is suitable for use as a micro-electronic gadget energizer. (author)

  4. Structural analysis of the transitional state of Arp2/3 complex activation by two actin-bound WCAs.

    Science.gov (United States)

    Boczkowska, Malgorzata; Rebowski, Grzegorz; Kast, David J; Dominguez, Roberto

    2014-01-01

    Actin filament nucleation and branching by Arp2/3 complex is activated by nucleation-promoting factors (NPFs), whose C-terminal WCA region contains binding sites for actin (W) and Arp2/3 complex (CA). It is debated whether one or two NPFs are required for activation. Here we present evidence in support of the two-NPF model and show that actin plays a crucial role in the interactions of two mammalian NPFs, N-WASP and WAVE2, with Arp2/3 complex. Competition between actin-WCA and glia maturation factor (GMF) for binding to Arp2/3 complex suggests that during activation the first actin monomer binds at the barbed end of Arp2. Based on distance constraints obtained by time-resolved fluorescence resonance energy transfer, we define the relative position of the two actin-WCAs on Arp2/3 complex and propose an atomic model of the 11-subunit transitional complex.

  5. Realistic calculations of correlations and final state interaction effects in the A(e,e'p)X process off complex nuclei

    CERN Document Server

    Alvioli, M; Morita, H

    2003-01-01

    A linked cluster expansion for the calculation of ground state observables of complex nuclei with realistic interactions has been used to calculate the ground state energy, density and momentum distribution of 16O and 40Ca. Using the same cluster expansion and the wave function and correlation parameters obtained from the energy calculation, we have evaluated the semi inclusive reaction A(e,e'p)X taking final state interaction (FSI) into account by a Glauber type approach; the comparison between the distorted and undistorted momentum distributions provides an estimate of the transparency of the nuclear medium to the propagation of the hit proton. The effect of color transparency is also included by considering the Finite Formation Time (FFT) that the hit hadron needs to reach its asymptotic physical state.

  6. Investigation of the lowest triplet state of the pyrochlorophyllide a-apomyoglobin complex by zero-field optically detected magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, R.H. (Boston Univ., MA); Hanlon, E.B.; Boxer, S.G.

    1982-06-04

    The zero-field fluorescence-detected triplet state magnetic resonance spectra have been obtained for the pyrochlorophyllide a-apomyoglobin complex at 2 K. The triplet state zero-field splittings and spin sublevel dynamics were detected on the resolved features of the structured low-temperature fluorescence. Structured fluorescence is not observed for pyrochlorophyllide a in an organic matrix under identical conditions. These data are interpreted in terms of the local binding site of the pyrochlorophyllide a chromophore in the protein and the low-temperature conformation of the protein matrix. 15 references, 1 figure, 1 table.

  7. Large fluorescence response by alcohol from a bis(benzoxazole)-zinc(II) complex: the role of excited state intramolecular proton transfer.

    Science.gov (United States)

    Wang, Junfeng; Chu, Qinghui; Liu, Xiumin; Wesdemiotis, Chrys; Pang, Yi

    2013-04-18

    The formation of a bis(HBO) anion is known to turn on the fluorescence to give red emission, via controlling the excited-state intramolecular proton transfer (ESIPT). The poor stability of the formed anion, however, hampered its application. The anion stability is found to be greatly improved by attaching the anion to Zn(2+) cation (i.e., forming zinc complex), whose emission is at λem ≈ 550 and 760 nm. Interestingly, addition of methanol to the zinc complex induces a remarkable red fluorescence (λem ≈ 630 nm, φfl ≈ 0.8). With the aid of spectroscopic studies ((1)H NMR, UV-vis, fluorescence, and mass spectra), the structures of the zinc complexes are characterized. The emission species is identified as a dimer-like structure. The study thus reveals an effective fluorescence switching mechanism that could further advance the application of ESIPT-based sensors.

  8. [Features of the dynamics of the state of health of the population residing near fuel and energy complex of the Republic of Kazakhstan].

    Science.gov (United States)

    Sraubaev, E N; Kulov, D B; Aĭtmagambetova, S S; Serik, B; Erdesov, N Zh

    2014-01-01

    There was performed the analysis of the state of health of the population residing near fuel and energy complex of the Republic of Kazakhstan in the vicinity of the fuel and energy complex of Kazakhstan, namely, of the Lebyazhinsky district of the Pavlodar region. The chemicals contained in the emissions of existing enterprises of the fuel and energy complex, have a direct impact on public health. There is noted an increase of some diseases such as respiratory diseases, complications of pregnancy, childbirths and the postpartum period, diseases of the nervous system, mental and behavioral disorders, neoplasms. The child population is particularly prone to the impact of air pollutants. In children from the studied area every year the incidence of asthma is increasing by 3 times, the incidence of neoplasms--by 2 times.

  9. Cationic copper (I) complexes with bulky 1,4-diaza-1,3-butadiene ligands - Synthesis, solid state structure and catalysis

    Science.gov (United States)

    Anga, Srinivas; Kottalanka, Ravi K.; Pal, Tigmansu; Panda, Tarun K.

    2013-05-01

    We report the full characterization of two glyoxal-based ligands N,N bis(diphenylmethyl)-1,4-diaza-1,3-butadiene ligand (DADPh2, 1) and more bulky N,N bis(triphenylmethyl)-1,4-diaza-1,3-butadiene ligand (DADPh3, 2) by the condensation reaction of glyoxal and diphenylmethanamine and triphenyl-methanamine respectively. The copper (I) complex of composition [Cu(DADPh2)2]PF6 (3) having two neutral bidentate N,N bis(diphenyl-methyl)-1,4-diaza-1,3-butadiene ligand was prepared by the reaction of [Cu(CH3CN)4]PF6 and 1 in 1:2 ratio in dichloromethane. In a similar reaction with N,N bis(triphenylmethyl)-1,4-diaza-1,3-butadiene ligand (2) and [Cu(CH3CN)4]PF6 in dichloromethane yielded corresponding heteroleptic copper (I) complex [Cu(DADPh3)(CH3CN)2]PF6 (4). Another copper (I) complex [Cu(DADPh2)(PPh3)]PF6 (5) can also be obtained by the one pot reaction involving ligand 1, [Cu(CH3CN)4]PF6 and triphenylphosphine. Solid state structures of all the five compounds were established by single crystal X-ray diffraction analysis. The solid state structures of the copper complexes 3-5 reveal a distorted tetrahedral geometry around the copper (I) centers. The copper complexes 3-5 were tested as catalysts for the coupling reaction of o-iodophenol and phenyl acetylene and it was observed that complex 4 exhibits the highest catalytic activity.

  10. Steady-State Configuration and Tension Calculations of Marine Cables Under Complex Currents via Separated Particle Swarm Optimization

    Institute of Scientific and Technical Information of China (English)

    徐雪松

    2014-01-01

    Under complex currents, the motion governing equations of marine cables are complex and nonlinear, and the calculations of cable configuration and tension become difficult compared with those under the uniform or simple currents. To obtain the numerical results, the usual Newton−Raphson iteration is often adopted, but its stability depends on the initial guessed solution to the governing equations. To improve the stability of numerical calculation, this paper proposed separated the particle swarm optimization, in which the variables are separated into several groups, and the dimension of search space is reduced to facilitate the particle swarm optimization. Via the separated particle swarm optimization, these governing nonlinear equations can be solved successfully with any initial solution, and the process of numerical calculation is very stable. For the calculations of cable configuration and tension of marine cables under complex currents, the proposed separated swarm particle optimization is more effective than the other particle swarm optimizations.

  11. A formal high oxidation state inverse-sandwich diuranium complex. A new route to f-block-metal bonds

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Dipti; Moro, Fabrizio; McMaster, Jonathan; Lewis, William; Blake, Alexander J.; Liddle, Stephen T. [Nottingham Univ. (United Kingdom). School of Chemistry

    2011-10-24

    Reduction of [U(Ts{sup Xy})(Cl)(thf)] [Ts{sup Xy}=HC(SiMe{sub 2}NAr){sub 3}; Ar=3,5-Me{sub 2}C{sub 6}H{sub 3}] with KC{sub 8} in toluene afforded the new arene-bridged diuranium complex 2, whereas reduction of 1 in aliphatic hydrocarbons resulted in C-N bond activation and formation of an imido-aryl complex, which exhibits an unusual ferromagnetic interaction between the two uranium centers. The synthetic utility of 2 was demonstrated by the first synthesis of a U-Co complex, [U(Ts{sup Xy})Co(CO){sub 3}(PPh{sub 3})].

  12. Elucidating connectivity and metal-binding structures of unlabeled paramagnetic complexes by 13C and 1H solid-state NMR under fast magic angle spinning.

    Science.gov (United States)

    Wickramasinghe, Nalinda P; Shaibat, Medhat A; Ishii, Yoshitaka

    2007-08-23

    Characterizing paramagnetic complexes in solids is an essential step toward understanding their molecular functions. However, methodologies to characterize chemical and electronic structures of paramagnetic systems at the molecular level have been notably limited, particularly for noncrystalline solids. We present an approach to obtain connectivities of chemical groups and metal-binding structures for unlabeled paramagnetic complexes by 13C and 1H high-resolution solid-state NMR (SSNMR) using very fast magic angle spinning (VFMAS, spinning speed >or=20 kHz). It is experimentally shown for unlabeled Cu(II)(Ala-Thr) that 2D 13C/1H correlation SSNMR under VFMAS provides the connectivity of chemical groups and assignments for the characterization of unlabeled paramagnetic systems in solids. We demonstrate that on the basis of the assignments provided by the VFMAS approach multiple 13C-metal distances can be simultaneously elucidated by a combination of measurements of 13C anisotropic hyperfine shifts and 13C T1 relaxation due to hyperfine interactions for this peptide-Cu(II) complex. It is also shown that an analysis of 1H anisotropic hyperfine shifts allows for the determination of electron-spin states in Fe(III)-chloroprotoporphyin-IX in solid states.

  13. Structural study of the thermal and photochemical spin states in the spin crossover complex [Fe(phen)2(NCSe)2].

    Science.gov (United States)

    MacLean, Elizabeth J; McGrath, Catherine M; O'Connor, Charles J; Sangregorio, Claudio; Seddon, Jon M W; Sinn, Ekk; Sowrey, Frank E; Teat, Simon J; Terry, Ann E; Vaughan, Gavin B M; Young, Nigel A

    2003-11-07

    The first structural data for [Fe(phen)(2)(NCSe)(2)] (obtained using the extraction method of sample preparation) in its high-spin, low-spin and LIESST induced metastable high-spin states have been recorded using synchrotron radiation single crystal diffraction. The space group for all of the spin states was found to be Pbcn. On cooling from the high-spin state (HS-1) at 292 K through the spin crossover at about 235 K to the low-spin state at 100 K (LS-1) the iron coordination environment changed to a more regular octahedral geometry and the Fe-N bond lengths decreased by 0.216 and 0.196 A (Fe-N(phen)) and 0.147 A (Fe-N(CSe)). When the low-spin state was illuminated with visible light at about 26 K, the structure of this LIESST induced metastable high-spin state (HS-2) was very similar to that of HS-1 with regards to the Fe-phen bond lengths, but there were some differences in the bond lengths in the Fe-NCSe unit between HS-1 and HS-2. When HS-2 was warmed in the dark to 50 K, the resultant low-spin state (LS-2) had an essentially identical structure to LS-1. In all spin states, all of the shortest intermolecular contacts (in terms of van der Waals radii) involved the NCSe ligand, which may be important in describing the cooperativity in the solid state. The quality of the samples was confirmed by magnetic susceptibility and IR measurements.

  14. Complex of Burkholderia cepacia lipase with transition state analogue of 1-phenoxy-2-acetoxybutane: biocatalytic, structural and modelling study.

    Science.gov (United States)

    Luić, M; Tomić, S; Lescić, I; Ljubović, E; Sepac, D; Sunjić, V; Vitale, L; Saenger, W; Kojic-Prodić, B

    2001-07-01

    In a series of four racemic phenoxyalkyl-alkyl carbinols, 1-phenoxy-2-hydroxybutane (1) is enantioselectively acetylated by Burkholderia cepacia (formerly Pseudomonas cepacia) lipase with an E value > or = 200, whereas for the other three racemates E was found to be analogue with a tetrahedral P-atom, (R(P),S(P))-O-(2R)-(1-phenoxybut-2-yl)methylphosphonic acid chloride was prepared and crystallized in complex with B. cepacia lipase. The X-ray structure of the complex was determined, allowing to compare the conformation of the inhibitor with results of molecular modelling.

  15. Up-regulation of Paxillin and Focal Adhesion Signaling follows Dystroglycan Complex deletions and promotes a Hypertensive State of Differentiation

    OpenAIRE

    Sen, Shamik; Tewari, Manorama; Zajac, Allison; Barton, Elisabeth; Sweeney, H. Lee; Discher, Dennis E.

    2011-01-01

    Anchorage to matrix is mediated for many cells not only by integrin-based focal adhesions but also by a parallel assembly of integral and peripheral membrane proteins known as the Dystroglycan Complex. Deficiencies in either dystrophin (mdx mice) or γ-sarcoglycan (γSG−/− mice) components of the Dystroglycan Complex lead to upregulation of numerous focal adhesion proteins, and the phosphoprotein paxillin proves to be among the most prominent. In mdx muscle, paxillin-Y31 and Y118 are both hyper...

  16. A complexity basis for phenomenology: How information states at criticality offer a new approach to understanding experience of self, being and time.

    Science.gov (United States)

    Hankey, Alex

    2015-12-01

    In the late 19th century Husserl studied our internal sense of time passing, maintaining that its deep connections into experience represent prima facie evidence for it as the basis for all investigations in the sciences: Phenomenology was born. Merleau-Ponty focused on perception pointing out that any theory of experience must accord with established aspects of biology i.e. be embodied. Recent analyses suggest that theories of experience require non-reductive, integrative information, together with a specific property connecting them to experience. Here we elucidate a new class of information states with just such properties found at the loci of control of complex biological systems, including nervous systems. Complexity biology concerns states satisfying self-organized criticality. Such states are located at critical instabilities, commonly observed in biological systems, and thought to maximize information diversity and processing, and hence to optimize regulation. Major results for biology follow: why organisms have unusually low entropies; and why they are not merely mechanical. Criticality states form singular self-observing systems, which reduce wave packets by processes of perfect self-observation associated with feedback gain g = 1. Analysis of their information properties leads to identification of a new kind of information state with high levels of internal coherence, and feedback loops integrated into their structure. The major idea presented here is that the integrated feedback loops are responsible for our 'sense of self', and also the feeling of continuity in our sense of time passing. Long-range internal correlations guarantee a unique kind of non-reductive, integrative information structure enabling such states to naturally support phenomenal experience. Being founded in complexity biology, they are 'embodied'; they also fulfill the statement that 'The self is a process', a singular process. High internal correlations and René Thom

  17. Studies of Structure and Dynamics of Light Harvesting Complex 1 of R. Sphaeroides by Solid State NMR

    Energy Technology Data Exchange (ETDEWEB)

    McDermott, Ann E [Columbia Univ., New York, NY (United States)

    2014-11-14

    Studies of the structure and dynamics of a light harvesting complex from photosynthetic bacteria are described. Using Nuclear Magnetic Resonance methods, we explored the idea that optical properties are modulated via a conformational switch in the BChl chromophores, in a way that provides benefits for the efficiency of energy conversion.

  18. Ab initio treatment of the chemical reaction precursor complex Cl(P-2)-HF. 2 : Bound states and infrared spectrum

    NARCIS (Netherlands)

    Fishchuk, A.V.; Groenenboom, G.C.; Avoird, A. van der

    2006-01-01

    Bound energy levels and properties of the Cl((2)p)-HF complex were obtained from full three-dimensional (3D) calculations, with the use of the ab initio computed diabatic potential surfaces from the preceding paper and the inclusion of spin-orbit coupling. For a better understanding of the dynamics

  19. Instream wood recruitment, channel complexity, and their relationship to stream ecology in forested headwater streams under alternative stable states

    Science.gov (United States)

    Livers, B.; Wohl, E.

    2015-12-01

    Human alteration to forests has had lasting effects on stream channels worldwide. Such land use changes affect how wood enters and is stored in streams as individual pieces and as logjams. Changes in wood recruitment affect the complexity and benefits wood can provide to the stream environment, such as zones of flow separation that store fine sediment and organic matter, increased nutrient processing, and greater habitat potential, which can enhance biota and cascade through stream-riparian ecosystems. Previous research in our study area shows that modern headwater streams flowing through old-growth, unmanaged forests have more wood than streams in young, managed forests, but does not explicitly evaluate how wood affects channel complexity or local ecology. 'Managed' refers to forests previously or currently exposed to human alteration. Alteration has long since ceased in some areas, but reduced wood loads in managed streams persist. Our primary objective was to quantify stream complexity metrics, with instream wood as a mediator, on streams across a gradient of management and disturbance histories in order to examine legacy effects of human alteration to forests. Data collected in the Southern Rocky Mountains include 24 2nd to 3rd order subalpine streams categorized into: old-growth unmanaged; younger, naturally disturbed unmanaged; and younger managed. We assessed instream wood loads and logjams and evaluated how they relate to channel complexity using a number of metrics, such as standard deviation of bed and banks, volume of pools, ratios of stream to valley lengths and stream to valley area, and diversity of substrate, gradient, and morphology. Preliminary results show that channel complexity is directly related to instream wood loads and is greatest in streams in old-growth. Related research in the field area indicates that streams with greater wood loads also have increased nutrient processing and greater abundance and diversity of aquatic insect predators.

  20. Azobenzene-derived tris-β-diketonate lanthanide complexes: reversible trans-to-cis photoisomerization in solution and solid state.

    Science.gov (United States)

    Lin, Li-Rong; Wang, Xuan; Wei, Gao-Ning; Tang, Hui-Hui; Zhang, Hui; Ma, Li-Hua

    2016-10-14

    Novel azobenzene-derived β-diketonates (4,4,5,5,6,6,6-heptafluoro-1-azobenzene-1,3-hexanedione (LA), 4,4,5,5,6,6,6-heptafluoro-1-(4-dimethylamino)azobenzene-1,3-hexanedione (LB)) were designed and their complexes with lanthanide cations (La(3+), Eu(3+), Gd(3+), Yb(3+)) were prepared and characterized by (1)H NMR, FT-IR, and elemental analysis. Three of the complexes were crystallized successfully and identified by X-ray diffraction. It was significant to find that LA showed remarkably reversible trans-to-cis isomerization properties, however, LB, bearing an electron donor compared with LA, slowed down the isomerization to an extent. The presence of Ln(iii) enhanced the reversible trans-to-cis isomerization properties of both LA and LB a little upon photoirradiation in organic solvents, and amazingly increased the fatigue resistance. In addition, the complexes doped in polymethyl methacrylate (PMMA) films produced a similar phenomenon as well as when in solution. Theoretical calculations based on time dependent density functional theory (TD-DFT) were performed for geometry optimization and to determine the excitation energies of LA and LB to gain further insight into the electronic structure of the complexes, and the data were consistent with the experimental results. The excellent reversible photoisomerization properties of the newly designed Ln(iii) complexes can offer important advantages that will help with the further study of these materials to reach their full potential in applications such as molecular switching devices.

  1. Mixed ligand complexation of some transition metal ions in solution and solid state: Spectral characterization, antimicrobial, antioxidant, DNA cleavage activities and molecular modeling

    Science.gov (United States)

    Shobana, Sutha; Dharmaraja, Jeyaprakash; Selvaraj, Shanmugaperumal

    2013-04-01

    Equilibrium studies of Ni(II), Cu(II) and Zn(II) mixed ligand complexes involving a primary ligand 5-fluorouracil (5-FU; A) and imidazoles viz., imidazole (him), benzimidazole (bim), histamine (hist) and L-histidine (his) as co-ligands(B) were carried out pH-metrically in aqueous medium at 310 ± 0.1 K with I = 0.15 M (NaClO4). In solution state, the stoichiometry of MABH, MAB and MAB2 species have been detected. The primary ligand(A) binds the central M(II) ions in a monodentate manner whereas him, bim, hist and his co-ligands(B) bind in mono, mono, bi and tridentate modes respectively. The calculated Δ log K, log X and log X' values indicate higher stability of the mixed ligand complexes in comparison to binary species. Stability of the mixed ligand complex equilibria follows the Irving-Williams order of stability. In vitro biological evaluations of the free ligand(A) and their metal complexes by well diffusion technique show moderate activities against common bacterial and fungal strains. Oxidative cleavage interaction of ligand(A) and their copper complexes with CT DNA is also studied by gel electrophoresis method in the presence of oxidant. In vitro antioxidant evaluations of the primary ligand(A), CuA and CuAB complexes by DPPH free radical scavenging model were carried out. In solid, the MAB type of M(II)sbnd 5-FU(A)sbnd his(B) complexes were isolated and characterized by various physico-chemical and spectral techniques. Both the magnetic susceptibility and electronic spectral analysis suggest distorted octahedral geometry. Thermal studies on the synthesized mixed ligand complexes show loss of coordinated water molecule in the first step followed by decomposition of the organic residues subsequently. XRD and SEM analysis suggest that the microcrystalline nature and homogeneous morphology of MAB complexes. Further, the 3D molecular modeling and analysis for the mixed ligand MAB complexes have also been carried out.

  2. Characterization of the low-temperature triplet state of chlorophyll in photosystem II core complexes: Application of phosphorescence measurements and Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Zabelin, Alexey A; Neverov, Konstantin V; Krasnovsky, Alexander A; Shkuropatova, Valentina A; Shuvalov, Vladimir A; Shkuropatov, Anatoly Ya

    2016-06-01

    Phosphorescence measurements at 77 K and light-induced FTIR difference spectroscopy at 95 K were applied to study of the triplet state of chlorophyll a ((3)Chl) in photosystem II (PSII) core complexes isolated from spinach. Using both methods, (3)Chl was observed in the core preparations with doubly reduced primary quinone acceptor QA. The spectral parameters of Chl phosphorescence resemble those in the isolated PSII reaction centers (RCs). The main spectral maximum and the lifetime of the phosphorescence corresponded to 955±1 nm and of 1.65±0.05 ms respectively; in the excitation spectrum, the absorption maxima of all core complex pigments (Chl, pheophytin a (Pheo), and β-carotene) were observed. The differential signal at 1667(-)/1628(+)cm(-1) reflecting a downshift of the stretching frequency of the 13(1)-keto C=O group of Chl was found to dominate in the triplet-minus-singlet FTIR difference spectrum of core complexes. Based on FTIR results and literature data, it is proposed that (3)Chl is mostly localized on the accessory chlorophyll that is in triplet equilibrium with P680. Analysis of the data suggests that the Chl triplet state responsible for the phosphorescence and the FTIR difference spectrum is mainly generated due to charge recombination in the reaction center radical pair P680(+)PheoD1(-), and the energy and temporal parameters of this triplet state as well as the molecular environment and interactions of the triplet-bearing Chl molecule are similar in the PSII core complexes and isolated PSII RCs.

  3. Solid-state C-13 and Co-59 NMR spectroscopy of C-13-methylcobalt(III) complexes with amine ligands

    DEFF Research Database (Denmark)

    Ooms, K J; Bernard, G M; Kadziola, A

    2009-01-01

    that the EFG tensors are either axially symmetric or close to being so but there is a wide range of C-Q values, from -40 MHz for the complex with X = H2O to -105 MHz with X = CN-. The Co chemical shift tensors are approximately axially symmetric with the spans. delta(11) - delta(33), ranging from 3700 to 5600...... ppm for X = H2O and CN-, respectively. The latter measurements also established the relative orientations of the Co EFG and chemical shift tensors. Density functional theory calculations of the Co-59 EFG and magnetic shielding tensors as well as of (1)J(Co-59, C-13) for the NO2- and N-3(-) complexes...

  4. STATE TRANSITION7-Dependent Phosphorylation Is Modulated by Changing Environmental Conditions, and Its Absence Triggers Remodeling of Photosynthetic Protein Complexes.

    Science.gov (United States)

    Bergner, Sonja Verena; Scholz, Martin; Trompelt, Kerstin; Barth, Johannes; Gäbelein, Philipp; Steinbeck, Janina; Xue, Huidan; Clowez, Sophie; Fucile, Geoffrey; Goldschmidt-Clermont, Michel; Fufezan, Christian; Hippler, Michael

    2015-06-01

    In plants and algae, the serine/threonine kinase STN7/STT7, orthologous protein kinases in Chlamydomonas reinhardtii and Arabidopsis (Arabidopsis thaliana), respectively, is an important regulator in acclimation to changing light environments. In this work, we assessed STT7-dependent protein phosphorylation under high light in C. reinhardtii, known to fully induce the expression of light-harvesting complex stress-related protein3 (LHCSR3) and a nonphotochemical quenching mechanism, in relationship to anoxia where the activity of cyclic electron flow is stimulated. Our quantitative proteomics data revealed numerous unique STT7 protein substrates and STT7-dependent protein phosphorylation variations that were reliant on the environmental condition. These results indicate that STT7-dependent phosphorylation is modulated by the environment and point to an intricate chloroplast phosphorylation network responding in a highly sensitive and dynamic manner to environmental cues and alterations in kinase function. Functionally, the absence of the STT7 kinase triggered changes in protein expression and photoinhibition of photosystem I (PSI) and resulted in the remodeling of photosynthetic complexes. This remodeling initiated a pronounced association of LHCSR3 with PSI-light harvesting complex I (LHCI)-ferredoxin-NADPH oxidoreductase supercomplexes. Lack of STT7 kinase strongly diminished PSII-LHCII supercomplexes, while PSII core complex phosphorylation and accumulation were significantly enhanced. In conclusion, our study provides strong evidence that the regulation of protein phosphorylation is critical for driving successful acclimation to high light and anoxic growth environments and gives new insights into acclimation strategies to these environmental conditions. © 2015 American Society of Plant Biologists. All Rights Reserved.

  5. The 1:2 Complex of Piperazine with Some Phenols:Hydrogen Bonding Pattern Involved in Transition States in Solution

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A novel model for the 1: 2 complex of piperazine with some phenols in solution is established and verified. In CDCl3 solution, one piperazine molecule is tied to two phenol molecules by hydrogen bonds of O-H---N and N-H---O. And the protons of >NH and -OH groups exchange quickly and simultaneously between the atoms of phenol oxygen and piperazine nitrogen.

  6. Solid State C-13 and H-2 NMR Investigations of Paramagnetic Ni(II)(acac)(2)L-2 Complexes

    DEFF Research Database (Denmark)

    Lennartson, A.; Christensen, Lene Ulrikke; McKenzie, C. J.

    2014-01-01

    Nine structurally related paramagnetic acetylacetonato nickel(II) complexes: [Ni(acac)(2)] and trans-[Ni(acac)(2)(X)(2)]nH/D2O, X = H2O, D2O, NH3, MeOH, PMePh2, PMe2Ph, or [dppe](1/2), n = 0 or 1, dppe = 1,2-his(diphenylphosphino)ethane, as well as cis-[Ni(F-6-acac)(2)(D2O)(2)], F-6-acac = hexafl...

  7. The apical complex protein Pals1 is required to maintain cerebellar progenitor cells in a proliferative state.

    Science.gov (United States)

    Park, Jun Young; Hughes, Lucinda J; Moon, Uk Yeol; Park, Raehee; Kim, Sang-Bae; Tran, Khoi; Lee, Ju-Seog; Cho, Seo-Hee; Kim, Seonhee

    2016-01-01

    Through their biased localization and function within the cell, polarity complex proteins are necessary to establish the cellular asymmetry required for tissue organization. Well-characterized germinal zones, mitogenic signals and cell types make the cerebellum an excellent model for addressing the crucial function of polarity complex proteins in the generation and organization of neural tissues. Deletion of the apical polarity complex protein Pals1 in the developing cerebellum results in a remarkably undersized cerebellum with disrupted layers in poorly formed folia and strikingly reduced granule cell production. We demonstrate that Pals1 is not only essential for cerebellum organogenesis, but also for preventing premature differentiation and thus maintaining progenitor pools in cerebellar germinal zones, including cerebellar granule neuron precursors in the external granule layer. In the Pals1 mouse mutants, the expression of genes that regulate the cell cycle was diminished, correlating with the loss of the proliferating cell population of germinal zones. Furthermore, enhanced Shh signaling through activated Smo cannot overcome impaired cerebellar cell generation, arguing for an epistatic role of Pals1 in proliferation capacity. Our study identifies Pals1 as a novel intrinsic factor that regulates the generation of cerebellar cells and Pals1 deficiency as a potential inhibitor of overactive mitogenic signaling.

  8. Synthesis of trans-bis(glycinato) copper(II) complex nanorods by room temperature solid-state reaction

    Institute of Scientific and Technical Information of China (English)

    WANG Li; LIU Lang; JIA Dianzeng; CAO Yali; XIN Xinquan

    2005-01-01

    Trans-[Cu(glyo)2(H2O)] nanoparticles with average diameters about 20-30 nm were prepared by one- step room temperature solid-state reaction. Trans-[Cu(glyo)2] nanorods with diameters ranging from 100 to 150 nm and lengths up to several μm were also prepared by one-step room temperature solid-state reaction in the presence of a suitable nonionic surfactant PEG400. The chemical composition and structural features of the products were investigated by elemental analyses, XRD, TG, SEM and TEM, respectively. The mechanisms of formation were also discussed.

  9. USE OF ENZYMES IN COMPLEX TREATMENT OF ANTIPHOSPHOLIPID SYNDROME IN WOMEN WITH REPRODUCTIVE LOSSES OF ANDIJAN STATE

    Directory of Open Access Journals (Sweden)

    Gulnoza Maniyozova

    2014-11-01

    Full Text Available Obstetric complications developing at antiphospholipid syndrome are serious medical-social problem. Seeking of the treatment methods sets conditions for urgency of the article reviewed. Enzyme preparations are widely applied for treatment of women with fecundity disorder and hemorheology changes. Research objective was in clinico-laboratorial evaluation of Serrata drug impact in antiphospholipid syndrome in women with reproductive losses of Andijan state. Methods: Data of 43 women in the non-pregnancy state with reproductive losses (RL in past history with revealed APS had been studied by us. Results: Thus, conducted therapy with Serrata was conductive to haemostasis. Conducted researches confirm the safety of application.

  10. Capturing the photo-signaling state of a photoreceptor in a steady-state fashion by binding a transition metal complex.

    Science.gov (United States)

    Yu, Pengyun; Song, Lei; Qin, Jun; Wang, Jianping

    2017-08-30

    Binding a small molecule to proteins causes conformational changes, but often to a limited extent. Here we demonstrate that the interaction of a CO-releasing molecule (CORM3) with a photoreceptor photoactive yellow protein (PYP) drives large structural changes in the latter. The interaction of CORM3 and a mutant of PYP, Met100Ala, not only triggers the isomerization of its chromophore, p-coumaric acid, from its anionic trans configuration to a protonated cis configuration, but also increases the content of β-sheet at the cost of α-helix and random coil in the secondary structure of the protein. The CORM3 derived Met100Ala is found to highly resemble the signaling state, which is one of the key photo-intermediates of this photoactive protein, in both protein local conformation and chromophore configuration. The organometallic reagents hold promise as protein engineering tools. This work highlights a novel approach to structurally accessing short lived intermediates of proteins in a steady-state fashion. This article is protected by copyright. All rights reserved. © 2017 The Protein Society.

  11. Solid state luminescence of CuI and CuNCS complexes with phenanthrolines and a new tris (aminomethyl) phosphine derived from N-methyl-2-phenylethanamine

    Energy Technology Data Exchange (ETDEWEB)

    Starosta, Radosław, E-mail: radoslaw.starosta@chem.uni.wroc.pl; Komarnicka, Urszula K.; Puchalska, Małgorzata

    2014-01-15

    A new tris (aminomethyl) phosphine derived from N-methyl-2-phenylethanamine P(CH{sub 2}N(CH{sub 3})CH{sub 2}CH{sub 2}Ph){sub 3} (1) has been synthesized and characterized by the NMR spectra. Also, three new copper(I) iodide or isothiocyanate complexes with 1 1,10-phenanthroline (phen) and 2,9-dimethyl-1,10-phenanthroline (dmp) [CuI(phen)P(CH{sub 2}N(CH{sub 3})CH{sub 2}CH{sub 2}Ph){sub 3}] (1P) CuI(dmp)P(CH{sub 2}N(CH{sub 3})CH{sub 2}CH{sub 2}Ph){sub 3}] (1I) and [CuNCS(dmp)P(CH{sub 2}N(CH{sub 3})CH{sub 2}CH{sub 2}Ph){sub 3}] (1T), have been synthesized and characterized by elemental analysis as well as studied by NMR, UV–vis, IR and luminescence spectroscopies. An X-ray structure of 1P complex revealed that the geometry around Cu(I) center in this complex is distorted pseudo-tetrahedral. Investigated complexes exhibit orange, rather weak photoluminescence in the solid state. This relatively low intensity may be related to the high flattening deformations of the molecular geometries in the excited triplet states On the basis of TDDFT calculations we confirmed that the absorbance and luminescence bands of (MX,MPR{sub 3})LCT as well as of (MX)LCT types result mainly from the transitions from the copper–iodine (or isothiocyanate) bonds and a small admixture of copper–phosphine bonds to antibonding orbitals of phen or dmp diimines. -- Highlights: • A novel tris(aminomethyl)phosphine is obtained from N-methyl-2-phenylethanamine. • Three new CuI and CuNCS complexes with phen or dmp and a novel phosphine are presented. • The obtained complexes are luminescent in the solid state. • Main absorbance and luminescence bands are of (MX,MPR{sub 3})LCT as well as (MX)LCT types.

  12. Conformational states of Ras complexed with the GTP analogue GppNHp or GppCH2p: implications for the interaction with effector proteins.

    Science.gov (United States)

    Spoerner, Michael; Nuehs, Andrea; Ganser, Petra; Herrmann, Christian; Wittinghofer, Alfred; Kalbitzer, Hans Robert

    2005-02-15

    The guanine nucleotide-binding protein Ras occurs in solution in two different states, state 1 and state 2, when the GTP analogue GppNHp is bound to the active center as detected by (31)P NMR spectroscopy. Here we show that Ras(wt).Mg(2+).GppCH(2)p also exists in two conformational states in dynamic equilibrium. The activation enthalpy DeltaH(++)(12) and the activation entropy DeltaS(++)(12) for the transition from state 1 to state 2 are 70 kJ mol(-1) and 102 J mol(-1) K(-1), within the limits of error identical to those determined for the Ras(wt).Mg(2+).GppNHp complex. The same is true for the equilibrium constants K(12) = [2]/[1] of 2.0 and the corresponding DeltaG(12) of -1.7 kJ mol(-1) at 278 K. This excludes a suggested specific effect of the NH group of GppNHp on the equilibrium. The assignment of the phosphorus resonance lines of the bound analogues has been done by two-dimensional (31)P-(31)P NOESY experiments which lead to a correction of the already reported assignments of bound GppNHp. Mutation of Thr35 in Ras.Mg(2+).GppCH(2)p to serine leads to a shift of the conformational equilibrium toward state 1. Interaction of the Ras binding domain (RBD) of Raf kinase or RalGDS with Ras(wt) or Ras(T35S) shifts the equilibrium completely to state 2. The (31)P NMR experiments suggest that, besides the type of the side chain of residue 35, a main contribution to the conformational equilibrium in Ras complexes with GTP and GTP analogues is the effective acidity of the gamma-phosphate group of the bound nucleotide. A reaction scheme for the Ras-effector interaction is presented which includes the existence of two conformations of the effector loop and a weak binding state.

  13. A COMPLEX ADAPTIVE STATE SYSTEM: NETWORKS, ARMS RACES AND MORAL HAZARDS Un sistema adaptativo complejo: Redes, carreras armamentistas y peligros morales

    Directory of Open Access Journals (Sweden)

    PABLO POLICZER

    2012-01-01

    Full Text Available Much of the debate over stateness in Latin America assumes that states should sustain basic levels of stability, and if they cannot, the question is why not. This article departs from the assumption of stability, by asking how the relationship between states and other actors has evolved over time. This departure requires a shift in focus: from stateness as referring to states and how they should operate, to stateness as referring to the relationships between states and other actors, and how they change over time. The article argues that such relationships can be understood as emergent complex adaptive systems (CAS, and considers three specific CAS mechanisms: networks, arms races, and moral hazards. This conceptual shift in how to think about states is especially challenging in a region historically accustomed to hierarchical governance.Buena parte del debate sobre la estatalidad en América Latina presupone que los estados deben mantener niveles básicos de estabilidad, y que si no pueden hacerlo, la pregunta es por qué no. Este artículo se aleja del supuesto de la estabilidad, al preguntar cómo la relación entre los estados y otros actores ha evolucionado con el tiempo. Esto requiere un cambio de enfoque: de estatalidad que se refiere a los estados y cómo debieran funcionar, a la estatalidad en referencia a las relaciones entre los estados y otros actores, y cómo éstas cambian con el tiempo. El artículo sostiene que este tipo de relaciones se puede entender como sistemas complejos adaptativos (SCA emergentes, y considera tres mecanismos específicos de SCA: redes, carreras armamentistas y peligros morales (moral hazards. Este cambio conceptual en laforma de pensar acerca de los estados es especialmente difícil en una región históricamente acostumbrada a la gobernanza jerárquica.

  14. Complex-scaled equation-of-motion coupled-cluster method with single and double substitutions for autoionizing excited states: theory, implementation, and examples.

    Science.gov (United States)

    Bravaya, Ksenia B; Zuev, Dmitry; Epifanovsky, Evgeny; Krylov, Anna I

    2013-03-28

    Theory and implementation of complex-scaled variant of equation-of-motion coupled-cluster method for excitation energies with single and double substitutions (EOM-EE-CCSD) is presented. The complex-scaling formalism extends the EOM-EE-CCSD model to resonance states, i.e., excited states that are metastable with respect to electron ejection. The method is applied to Feshbach resonances in atomic systems (He, H(-), and Be). The dependence of the results on one-electron basis set is quantified and analyzed. Energy decomposition and wave function analysis reveal that the origin of the dependence is in electron correlation, which is essential for the lifetime of Feshbach resonances. It is found that one-electron basis should be sufficiently flexible to describe radial and angular electron correlation in a balanced fashion and at different values of the scaling parameter, θ. Standard basis sets that are optimized for not-complex-scaled calculations (θ = 0) are not sufficiently flexible to describe the θ-dependence of the wave functions even when heavily augmented by additional sets.

  15. Structure, bonding and energetics of N-heterocyclic carbene (NHC) stabilized low oxidation state group 2 (Be, Mg, Ca, Sr and Ba) metal complexes: A theoretical study

    Indian Academy of Sciences (India)

    Ashim Baishya; V Rao Mundlapati; Sharanappa Nembenna; Himansu S Biswal

    2014-11-01

    A series of N-heterocyclic carbene stabilized low oxidation state group 2 metal halide and hydrides with metal-metal bonds ([L(X) M-M(X) L]; L = NHC ((CHNH)2C:), M = Be, Mg, Ca, Sr and Ba, and X = Cl or H) has been studied by computational methods. The main objective of this study is to predict whether it is possible to stabilize neutral ligated low oxidation state alkaline-earth metal complexes with metal-metal bonds. The homolytic metal-metal Bond Dissociation Energy (BDE) calculation, Natural Bond Orbital (NBO) and Energy Decomposition Analyses (EDA) on density functional theory (DFT) optimized [L(X)M-M(X)L] complexes revealed that they are as stable as their -diketiminate, guanidinate and -diimine counterparts. The optimized structures of the complexes are in trans-linear geometries. The bond order analyses such as Wiberg Bond Indices (WBI) and Fuzzi Bond Order (FBO) confirm the existence of single bond between two metal atoms, and it is covalent in nature.

  16. Quantum state-resolved differential cross sections for complex-forming chemical reactions: Asymmetry is the rule, symmetry the exception

    Energy Technology Data Exchange (ETDEWEB)

    Larrégaray, Pascal, E-mail: pascal.larregaray@u-bordeaux.fr; Bonnet, Laurent, E-mail: laurent.bonnet@u-bordeaux.fr [ISM, UMR 5255, CNRS, F-33400 Talence (France); ISM, UMR 5255, Univ. Bordeaux, F-33400 Talence (France)

    2015-10-14

    We argue that statistical theories are generally unable to accurately predict state-resolved differential cross sections for triatomic bimolecular reactions studied in beam experiments, even in the idealized limit where the dynamics are fully chaotic. The basic reason is that quenching of interferences between partial waves is less efficient than intuitively expected, especially around the poles.

  17. Transient-state kinetic analysis of complex formation between photoprotein clytin and GFP from jellyfish Clytia gregaria

    NARCIS (Netherlands)

    Eremeeva, Elena V.; Berkel, Van Willem J.H.; Vysotski, Eugene S.

    2016-01-01

    Luminous organisms use different protein-mediated strategies to modulate light emission color. Here, we report the transient-state kinetic studies of the interaction between photoprotein clytin from Clytia gregaria and its antenna protein, cgreGFP. We propose that cgreGFP forms a transient comple

  18. Transient-state kinetic analysis of complex formation between photoprotein clytin and GFP from jellyfish Clytia gregaria

    NARCIS (Netherlands)

    Eremeeva, Elena V.; Berkel, Van Willem J.H.; Vysotski, Eugene S.

    2016-01-01

    Luminous organisms use different protein-mediated strategies to modulate light emission color. Here, we report the transient-state kinetic studies of the interaction between photoprotein clytin from Clytia gregaria and its antenna protein, cgreGFP. We propose that cgreGFP forms a transient

  19. High-resolution steady-state and time-resolved luminescence studies on the complexes of Eu(III) with aromatic or aliphatic carboxylic acids.

    Science.gov (United States)

    Marmodée, Bettina; de Klerk, Joost S; Ariese, Freek; Gooijer, Cees; Kumke, Michael U

    2009-10-12

    Eu(III) luminescence spectroscopy, both in the steady-state and the time-resolved mode, is an appropriate technique to study the properties of complexes between heavy metal ions and humic substances (HS), which play a key role in the distribution of metal species in the environment. Unfortunately, room temperature luminescence spectra of Eu(III) complexes with aromatic and aliphatic carboxylic acids - model compounds of HS binding sites - are too broad to fully exploit their potential analytical information content. It is shown that under cryogenic conditions fluorescence-line-narrowing (FLN) is achieved, and the highly resolved spectra provide detailed information on the complexes. Ten model ligands were investigated. Total luminescence spectra (TLS) were recorded, using the (5)D(0)(7)F(1) and (5)D(0)-->(7)F(2) transitions for emission. The energy of the excitation transition depends on the ligand involved and the structure and composition of the complex. For most ligands, discontinuities in the high-resolution TLS indicated that more species, i.e. distinct complex structures, coexisted in the sample. Selective excitation was performed to measure the species-associated luminescence decay times tau. The latter strongly depend on nearby OH oscillators from coordinating water molecules or ligand hydroxyl groups. Furthermore, the asymmetry ratios r, defined as the intensity ratio of the (5)D(0)-->(7)F(2) and (5)D(0)-->(7)F(1) transitions, were calculated and the variation of the excitation energy E(exc) with the splitting of the (7)F(1) triplet (DeltaE) was determined, which yielded the crystal field strength parameter N(nu)(B(2q)), as well as the crystal field parameters B(20) and B(22). An in-depth analysis of the results is presented, providing detailed information on the number of coexisting complexes, their stoichiometry, the number of water molecules in the first coordination sphere and their geometry (symmetry point group).

  20. Solid-state flurbiprofen and methyl-β-cyclodextrin inclusion complexes prepared using a single-step, organic solvent-free supercritical fluid process.

    Science.gov (United States)

    Rudrangi, Shashi Ravi Suman; Kaialy, Waseem; Ghori, Muhammad U; Trivedi, Vivek; Snowden, Martin J; Alexander, Bruce David

    2016-07-01

    The aim of this study was to enhance the apparent solubility and dissolution properties of flurbiprofen through inclusion complexation with cyclodextrins. Especially, the efficacy of supercritical fluid technology as a preparative technique for the preparation of flurbiprofen-methyl-β-cyclodextrin inclusion complexes was evaluated. The complexes were prepared by supercritical carbon dioxide processing and were evaluated by solubility, differential scanning calorimetry, X-ray powder diffraction, scanning electron microscopy, practical yield, drug content estimation and in vitro dissolution studies. Computational molecular docking studies were conducted to study the possibility of molecular arrangement of inclusion complexes between flurbiprofen and methyl-β-cyclodextrin. The studies support the formation of stable molecular inclusion complexes between the drug and cyclodextrin in a 1:1 stoichiometry. In vitro dissolution studies showed that the dissolution properties of flurbiprofen were significantly enhanced by the binary mixtures prepared by supercritical carbon dioxide processing. The amount of flurbiprofen dissolved into solution alone was very low with 1.11±0.09% dissolving at the end of 60min, while the binary mixtures processed by supercritical carbon dioxide at 45°C and 200bar released 99.39±2.34% of the drug at the end of 30min. All the binary mixtures processed by supercritical carbon dioxide at 45°C exhibited a drug release of more than 80% within the first 10min irrespective of the pressure employed. The study demonstrated the single step, organic solvent-free supercritical carbon dioxide process as a promising approach for the preparation of inclusion complexes between flurbiprofen and methyl-β-cyclodextrin in solid-state.

  1. Encapsulating model complexity and landscape-scale analyses of state-and-transition simulation models: an application of ecoinformatics and juniper encroachment in sagebrush steppe ecosystems

    Science.gov (United States)

    O'Donnell, Michael

    2015-01-01

    State-and-transition simulation modeling relies on knowledge of vegetation composition and structure (states) that describe community conditions, mechanistic feedbacks such as fire that can affect vegetation establishment, and ecological processes that drive community conditions as well as the transitions between these states. However, as the need for modeling larger and more complex landscapes increase, a more advanced awareness of computing resources becomes essential. The objectives of this study include identifying challenges of executing state-and-transition simulation models, identifying common bottlenecks of computing resources, developing a workflow and software that enable parallel processing of Monte Carlo simulations, and identifying the advantages and disadvantages of different computing resources. To address these objectives, this study used the ApexRMS® SyncroSim software and embarrassingly parallel tasks of Monte Carlo simulations on a single multicore computer and on distributed computing systems. The results demonstrated that state-and-transition simulation models scale best in distributed computing environments, such as high-throughput and high-performance computing, because these environments disseminate the workloads across many compute nodes, thereby supporting analysis of larger landscapes, higher spatial resolution vegetation products, and more complex models. Using a case study and five different computing environments, the top result (high-throughput computing versus serial computations) indicated an approximate 96.6% decrease of computing time. With a single, multicore compute node (bottom result), the computing time indicated an 81.8% decrease relative to using serial computations. These results provide insight into the tradeoffs of using different computing resources when research necessitates advanced integration of ecoinformatics incorporating large and complicated data inputs and models. - See more at: http://aimspress.com

  2. “Covalent Hydration” Reactions in Model Monomeric Ru 2,2'-Bipyridine Complexes: Thermodynamic Favorability as a Function of Metal Oxidation and Overall Spin States

    Energy Technology Data Exchange (ETDEWEB)

    Ozkanlar, Abdullah; Cape, Jonathan L.; Hurst, James K.; Clark, Aurora E.

    2011-09-05

    Density functional theory (DFT) has been used to investigate the plausibility of water addition to the simple mononuclear ruthenium complexes, [(NH{sub 3}){sub 3}(bpy)Ru=O]{sup 2+}/{sup 3+} and [(NH{sub 3}){sub 3}(bpy)RuOH]{sup 3+}, in which the OH fragment adds to the 2,2{prime}-bipyridine (bpy) ligand. Activation of bpy toward water addition has frequently been postulated within the literature, although there exists little definitive experimental evidence for this type of 'covalent hydration'. In this study, we examine the energetic dependence of the reaction upon metal oxidation state, overall spin state of the complex, as well as selectivity for various positions on the bipyridine ring. The thermodynamic favorability is found to be highly dependent upon all three parameters, with free energies of reaction that span favorable and unfavorable regimes. Aqueous addition to [(NH{sub 3}){sub 3}(bpy)Ru=O]{sup 3+} was found to be highly favorable for the S = 1/2 state, while reduction of the formal oxidation state on the metal center makes the reaction highly unfavorable. Examination of both facial and meridional isomers reveals that when bipyridine occupies the position trans to the ruthenyl oxo atom, reactivity toward OH addition decreases and the site preferences are altered. The electronic structure and spectroscopic signatures (EPR parameters and simulated spectra) have been determined to aid in recognition of 'covalent hydration' in experimental systems. EPR parameters are found to uniquely characterize the position of the OH addition to the bpy as well as the overall spin state of the system.

  3. Encapsulating model complexity and landscape-scale analyses of state-and-transition simulation models: an application of ecoinformatics and juniper encroachment in sagebrush steppe ecosystems

    Directory of Open Access Journals (Sweden)

    Michael S. O'Donnell

    2015-06-01

    Full Text Available State-and-transition simulation modeling relies on knowledge of vegetation composition and structure (states that describe community conditions, mechanistic feedbacks such as fire that can affect vegetation establishment, and ecological processes that drive community conditions as well as the transitions between these states. However, as the need for modeling larger and more complex landscapes increase, a more advanced awareness of computing resources becomes essential. The objectives of this study include identifying challenges of executing state-and-transition simulation models, identifying common bottlenecks of computing resources, developing a workflow and software that enable parallel processing of Monte Carlo simulations, and identifying the advantages and disadvantages of different computing resources. To address these objectives, this study used the ApexRMS® SyncroSim software and embarrassingly parallel tasks of Monte Carlo simulations on a single multicore computer and on distributed computing systems. The results demonstrated that state-and-transition simulation models scale best in distributed computing environments, such as high-throughput and high-performance computing, because these environments disseminate the workloads across many compute nodes, thereby supporting analysis of larger landscapes, higher spatial resolution vegetation products, and more complex models. Using a case study and five different computing environments, the top result (high-throughput computing versus serial computations indicated an approximate 96.6% decrease of computing time. With a single, multicore compute node (bottom result, the computing time indicated an 81.8% decrease relative to using serial computations. These results provide insight into the tradeoffs of using different computing resources when research necessitates advanced integration of ecoinformatics incorporating large and complicated data inputs and models.

  4. Photobehavior of copper(I) compounds. 4. Role of the triplet state of (arylphosphine)copper(I) complexes in the photosensitized isomerization dienes

    Energy Technology Data Exchange (ETDEWEB)

    Liaw, B.; Orchard, S.W.; Kutal, C.

    1988-04-20

    Photoisomerization of cis- and trans-piperylene can be sensitized with high quantum efficiency by Cu(diphos)BH/sub 4/ (diphos is 1,2-bis(diphenylphosphino)ethane) and Cu(prophos)BH/sub 4/ (prophos is 1,3-bis(diphenylphosphino)propane). Sensitization is accompanied by quenching of the emissive /sup 3/(/sigma/-a/sub /pi//) excited state in each copper(I) complex, and the two processes occur with identical Stern-Volmer kinetics. Measurements of the trans/cis diene ratio at the photostationary state can be used to estimate the triplet-state energy as 60-61 kcal for Cu(diphos)BH/sub 4/ and > 61 kcal for Cu(prophos)BH/sub 4/; additional evidence suggests that 66-67 kcal is a reasonable value for the latter complex. Collectively, the results support the assignment of triplet-triplet energy transfer as the primary mechanism for sensitization and quenching in these systems. This mechanism also can accommodate earlier reports that Cu(diphos)BH/sub 4/ and Cu(prophos)BH/sub 4/ sensitize the valence isomerization of norbornadiene to quadricyclene with markedly different quantum efficiencies. 17 refs., 6 figs., 2 tabs.

  5. Upregulation of paxillin and focal adhesion signaling follows Dystroglycan Complex deletions and promotes a hypertensive state of differentiation.

    Science.gov (United States)

    Sen, Shamik; Tewari, Manorama; Zajac, Allison; Barton, Elisabeth; Sweeney, H Lee; Discher, Dennis E

    2011-01-01

    Anchorage to matrix is mediated for many cells not only by integrin-based focal adhesions but also by a parallel assembly of integral and peripheral membrane proteins known as the Dystroglycan Complex. Deficiencies in either dystrophin (mdx mice) or γ-sarcoglycan (γSG(-/-) mice) components of the Dystroglycan Complex lead to upregulation of numerous focal adhesion proteins, and the phosphoprotein paxillin proves to be among the most prominent. In mdx muscle, paxillin-Y31 and Y118 are both hyper-phosphorylated as are key sites in focal adhesion kinase (FAK) and the stretch-stimulatable pro-survival MAPK pathway, whereas γSG(-/-) muscle exhibits more erratic hyper-phosphorylation. In cultured myotubes, cell tension generated by myosin-II appears required for localization of paxillin to adhesions while vinculin appears more stably integrated. Overexpression of wild-type (WT) paxillin has no obvious effect on focal adhesion density or the physical strength of adhesion, but WT and a Y118F mutant promote contractile sarcomere formation whereas a Y31F mutant shows no effect, implicating Y31 in striation. Self-peeling of cells as well as Atomic Force Microscopy (AFM) probing of cells with or without myosin-II inhibition indicate an increase in cell tension within paxillin-overexpressing cells. However, prednisolone, a first-line glucocorticoid for muscular dystrophies, decreases cell tension without affecting paxillin at adhesions, suggesting a non-linear relationship between paxillin and cell tension. Hypertension that results from upregulation of integrin adhesions is thus a natural and treatable outcome of Dystroglycan Complex down-regulation.

  6. MS-CASPT2 study of hole transfer in guanine-indole complexes using the generalized Mulliken-Hush method: effective two-state treatment.

    Science.gov (United States)

    Butchosa, C; Simon, S; Blancafort, L; Voityuk, A

    2012-07-12

    Because hole transfer from nucleobases to amino acid residues in DNA-protein complexes can prevent oxidative damage of DNA in living cells, computational modeling of the process is of high interest. We performed MS-CASPT2 calculations of several model structures of π-stacked guanine and indole and derived electron-transfer (ET) parameters for these systems using the generalized Mulliken-Hush (GMH) method. We show that the two-state model commonly applied to treat thermal ET between adjacent donor and acceptor is of limited use for the considered systems because of the small gap between the ground and first excited states in the indole radical cation. The ET parameters obtained within the two-state GMH scheme can deviate significantly from the corresponding matrix elements of the two-state effective Hamiltonian based on the GMH treatment of three adiabatic states. The computed values of diabatic energies and electronic couplings provide benchmarks to assess the performance of less sophisticated computational methods.

  7. A thermogravimetric analysis (TGA) method developed for estimating the stoichiometric ratio of solid-state {alpha}-cyclodextrin-based inclusion complexes

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Yuxiang; Wang, Jinpeng; Bashari, Mohanad; Hu, Xiuting [The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122 (China); Feng, Tao [School of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai 201418 (China); Xu, Xueming [The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122 (China); Jin, Zhengyu, E-mail: jinlab2008@yahoo.com [The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122 (China); Tian, Yaoqi, E-mail: yqtian@jiangnan.edu.cn [The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122 (China)

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer We develop a TGA method for the measurement of the stoichiometric ratio. Black-Right-Pointing-Pointer A series of formulas are deduced to calculate the stoichiometric ratio. Black-Right-Pointing-Pointer Four {alpha}-CD-based inclusion complexes were successfully prepared. Black-Right-Pointing-Pointer The developed method is applicable. - Abstract: An approach mainly based on thermogravimetric analysis (TGA) was developed to evaluate the stoichiometric ratio (SR, guest to host) of the guest-{alpha}-cyclodextrin (Guest-{alpha}-CD) inclusion complexes (4-cresol-{alpha}-CD, benzyl alcohol-{alpha}-CD, ferrocene-{alpha}-CD and decanoic acid-{alpha}-CD). The present data obtained from Fourier transform-infrared (FT-IR) spectroscopy showed that all the {alpha}-CD-based inclusion complexes were successfully prepared in a solid-state form. The stoichiometric ratios of {alpha}-CD to the relative guests (4-cresol, benzyl alcohol, ferrocene and decanoic acid) determined by the developed method were 1:1, 1:2, 2:1 and 1:2, respectively. These SR data were well demonstrated by the previously reported X-ray diffraction (XRD) method and the NMR confirmatory experiments, except the SR of decanoic acid with a larger size and longer chain was not consistent. It is, therefore, suggested that the TGA-based method is applicable to follow the stoichiometric ratio of the polycrystalline {alpha}-CD-based inclusion complexes with smaller and shorter chain guests.

  8. Development of InP solid state detector and liquid scintillator containing metal complex for measurement of pp/7Be solar neutrinos and neutrinoless double beta decay

    Science.gov (United States)

    Fukuda, Yoshiyuki; Moriyama, Shigetaka

    2012-07-01

    A large volume solid state detector using a semi-insulating Indium Phosphide (InP) wafer have been developed for measurement of pp/7Be solar neutrinos. Basic performance such as the charge collection efficiency and the energy resolution were measured by 60% and 20%, respectively. In order to detect two gammas (115keV and 497keV) from neutrino capture, we have designed hybrid detector which consist InP detector and liquid xenon scintillator for IPNOS experiment. New InP detector with thin electrode (Cr 50Å- Au 50Å). For another possibility, an organic liquid scintillator containing indium complex and zirconium complex were studied for a measurement of low energy solar neutrinos and neutrinosless double beta decay, respectively. Benzonitrile was chosen as a solvent because of good solubility for the quinolinolato complexes (2 wt%) and of good light yield for the scintillation induced by gamma-ray irradiation. The photo-luminescence emission spectra of InQ3 and ZrQ4 in benzonitrile was measured and liquid scintillator cocktail using InQ3 and ZrQ4 (50mg) in benzonitrile solutions (20 mL) with secondary scintillators with PPO (100mg) and POPOP (10mg) was made. The energy spectra of incident gammas were measured, and they are first results of the gamma-ray energy spectra using luminescent of metal complexes.

  9. A cyclometalated iridium(III) complex with enhanced phosphorescence emission in the solid state (EPESS): synthesis, characterization and its application in bioimaging.

    Science.gov (United States)

    Wu, Huazhou; Yang, Tianshe; Zhao, Qiang; Zhou, Jing; Li, Chunyan; Li, Fuyou

    2011-03-07

    Iridium(III) complexes with intense phosphorescence in solution have been widely applied in organic light-emitting diodes, chemosensors and bioimaging. However, little attention has been paid to iridium(III) complexes showing weak phosphorescence in solution and enhanced phosphorescence emission in the solid state (EPESS). In the present study, two β-diketonate ligands with different degrees of conjugation, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HL1) and 1-phenyl-3-methyl-4-phenylacetyl-5-pyrazolone (HL2), have been synthesized to be used as ancillary ligands for two iridium(III) complexes, Ir(ppy)(2)(L1) and Ir(ppy)(2)(L2) (Hppy = 2-phenylpyridine). The two complexes have been characterized by single-crystal X-ray crystallography, (1)H NMR and elemental analysis. Interestingly, Ir(ppy)(2)(L1) is EPESS-active whereas Ir(ppy)(2)(L2) exhibits moderately intense emission both in solution and as a neat film, indicating that the degree of conjugation of the β-diketone ligands determines the EPESS-activity. The single-crystal X-ray analysis has indicated that there are π-π interactions between the adjacent ppy ligands in Ir(ppy)(2)(L1) but not in Ir(ppy)(2)(L2). Finally, EPESS-active Ir(ppy)(2)(L1) has been successfully embedded in polymer nanoparticles and used as a luminescent label in bioimaging.

  10. Estimation of multi-state life table functions and their variability from complex survey data using the SPACE Program

    Directory of Open Access Journals (Sweden)

    Liming Cai

    2010-01-01

    Full Text Available The multistate life table (MSLT model is an important demographic method to document life cycle processes. In this study, we present the SPACE (Stochastic Population Analysis for Complex Events program to estimate MSLT functions and their sampling variability. It has several advantages over other programs, including the use of microsimulation and the bootstrap method to estimate the sampling variability. Simulation enables researchers to analyze a broader array of statistics than the deterministic approach, and may be especially advantageous in investigating distributions of MSLT functions. The bootstrap method takes sample design into account to correct the potential bias in variance estimates.

  11. An Integrated Approach for Structural Characterization of Complex Solid State Electrolytes: The Case of Lithium Lanthanum Titanate

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yongqiang [ORNL; Bi, [ORNL; Huq, Ashfia [ORNL; Feygenson, Mikhail [ORNL; Bridges, Craig A [ORNL; Paranthaman, Mariappan Parans [ORNL; Sumpter, Bobby G [ORNL

    2014-01-01

    Neutron scattering and first principles simulation are integrated to reveal the atomic-level to nanoscale structure of lithium lanthanum titanate (LLTO), a representative solid electrolyte material with applications in Li-ion batteries. The integrated approach solves the hierarchical local structure of LLTO in detail, including the coupled chemical order and topological distortion, as well as their correlation length scale and the spatial modulation with coherent boundaries. Ab initio molecular dynamics simulations are used to map out the distribution of the mobile ions and identify the migration pathway. Overall, this integrated approach provides a powerful means for detailed study of materials with complex local chemical and topological environment.

  12. Satellite remote sensing of landscape freeze/thaw state dynamics for complex Topography and Fire Disturbance Areas Using multi-sensor radar and SRTM digital elevation models

    Science.gov (United States)

    Podest, Erika; McDonald, Kyle; Kimball, John; Randerson, James

    2003-01-01

    We characterize differences in radar-derived freeze/thaw state, examining transitions over complex terrain and landscape disturbance regimes. In areas of complex terrain, we explore freezekhaw dynamics related to elevation, slope aspect and varying landcover. In the burned regions, we explore the timing of seasonal freeze/thaw transition as related to the recovering landscape, relative to that of a nearby control site. We apply in situ biophysical measurements, including flux tower measurements to validate and interpret the remotely sensed parameters. A multi-scale analysis is performed relating high-resolution SAR backscatter and moderate resolution scatterometer measurements to assess trade-offs in spatial and temporal resolution in the remotely sensed fields.

  13. Calculating vibrational spectra without determining excited eigenstates: Solving the complex linear equations of damped response theory for vibrational configuration interaction and vibrational coupled cluster states.

    Science.gov (United States)

    Godtliebsen, Ian H; Christiansen, Ove

    2015-10-07

    It is demonstrated how vibrational IR and Raman spectra can be calculated from damped response functions using anharmonic vibrational wave function calculations, without determining the potentially very many eigenstates of the system. We present an implementation for vibrational configuration interaction and vibrational coupled cluster, and describe how the complex equations can be solved using iterative techniques employing only real trial vectors and real matrix-vector transformations. Using this algorithm, arbitrary frequency intervals can be scanned independent of the number of excited states. Sample calculations are presented for the IR-spectrum of water, Raman spectra of pyridine and a pyridine-silver complex, as well as for the infra-red spectrum of oxazole, and vibrational corrections to the polarizability of formaldehyde.

  14. Satellite remote sensing of landscape freeze/thaw state dynamics for complex Topography and Fire Disturbance Areas Using multi-sensor radar and SRTM digital elevation models

    Science.gov (United States)

    Podest, Erika; McDonald, Kyle; Kimball, John; Randerson, James

    2003-01-01

    We characterize differences in radar-derived freeze/thaw state, examining transitions over complex terrain and landscape disturbance regimes. In areas of complex terrain, we explore freezekhaw dynamics related to elevation, slope aspect and varying landcover. In the burned regions, we explore the timing of seasonal freeze/thaw transition as related to the recovering landscape, relative to that of a nearby control site. We apply in situ biophysical measurements, including flux tower measurements to validate and interpret the remotely sensed parameters. A multi-scale analysis is performed relating high-resolution SAR backscatter and moderate resolution scatterometer measurements to assess trade-offs in spatial and temporal resolution in the remotely sensed fields.

  15. Phobias of attachment-related inner states in the psychotherapy of adult survivors of childhood complex trauma.

    Science.gov (United States)

    Liotti, Giovanni

    2013-11-01

    The clinical case described in this article illustrates the value of taking into account the dynamics of disorganized attachment in the assessment of attachment-related phobias (phobia of attachment and phobia of attachment loss) during the psychotherapy of chronically traumatized patients. These seemingly opposite phobias typically coexist in the same patient, appear as phobias of both inner states (affect phobias) and relational experiences, and are linked to dissociated representations of self-with-other. Theory and research on attachment disorganization provide a clinician-friendly conceptual framework for capturing both the intrapsychic (e.g., intrusive and nonintegrated mental states) and the relational (e.g., dramatic unsolvable dilemmas in interpersonal exchanges) aspects of the attachment-related phobias. The therapeutic strategy and the key interventions that logically follow from a case formulation based on this conceptual framework are examined.

  16. Sub-picosecond time resolved infrared spectroscopy of high-spin state formation in Fe(II) spin crossover complexes

    DEFF Research Database (Denmark)

    Døssing, Anders Rørbæk; Wolf, Matthias M. N.; Gross, Ruth

    2008-01-01

      The photoinduced low-spin (S = 0) to high-spin (S = 2) transition of the iron(II) spin-crossover systems [Fe(btpa)](PF6)2 and [Fe(b(bdpa))](PF6)2 in solution have been studied for the first time by means of ultrafast transient infrared spectroscopy at room temperature. Negative and positive...... absorption cross sections. The simulated infrared difference spectra are dominated by an increase of the absorption cross section upon high-spin state formation in accordance with the experimental infrared spectra....... infrared difference bands between 1000 and 1065 cm-1 that appear within the instrumental system response time of 350 fs after excitation at 387 nm display the formation of the vibrationally unrelaxed and hot high-spin 5T2 state. Vibrational relaxation is observed and characterized by the time constants 9...

  17. Preliminary assessment of nuclear energy centers and energy systems complexes in the western United States. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gottlieb, P.; Robinson, J.H.; Smith, D.R.

    1978-02-01

    The Nuclear Energy Center siting opportunities in the eleven western states have been systematically examined. The study area has been divided into 10-mile by 10-mile grid cells, and each cell has been evaluated in terms of overall suitability and site-related costs. Composite suitability consists of a weighted sum of ten important nuclear power plant siting issues; the particular weights used for this study were decided by a Delphi session of twenty individuals with energy facility siting expertise, with at least one representative from each of the eleven western states. Site-related costs consist of the additional expenditures required for seismic hardening (in seismically active areas), electric power transmission lines (for sites significantly far from load centers), and wet/dry cooling system costs (limited water availability and/or high summer temperatures).

  18. Structural dynamics of nitrosylruthenium isomeric complexes studied with steady-state and transient pump-probe infrared spectroscopies

    Science.gov (United States)

    Zhao, Yan; Yang, Fan; Wang, Jianru; Yu, Pengyun; Pan, Huifen; Wang, Hongfei; Wang, Jianping

    2016-09-01

    The characteristic nitrosyl stretching (NO) in the region of 1800-1900 cm- 1 was used to study the geometric and ligand effect on two nitrosylruthenium complexes, namely [Ru(OAc)(2QN)2NO] (QN = 2-chloro-8-quinolinol (H2cqn) or QN = 2-methyl-8-quinolinol (H2mqn)). The NO stretching frequency (νNO) was found in the following order: νcis-1 (2cqn) > νcis-2 (2cqn) > νcis-1 (2mqn) > νtrans (2mqn). The results exhibited a spectral sensitivity of the NO mode to both charge distribution and ligand arrangement, which was supported by ab initio computations and natural bond orbital (NBO) analyses. Further, the vibrational population of the vibrationally excited NO stretching mode was found to relax on the order of 7-10 ps, showing less than 30% variation from one isomer to another, which were explained on the basis of NO local structures and solute-solvent interactions in these isomeric nitrosylruthenium complexes.

  19. Symmetry breaking and light-induced spin-state trapping in a mononuclear FeII complex with the two-step thermal conversion

    Science.gov (United States)

    Buron-Le Cointe, M.; Ould Moussa, N.; Trzop, E.; Moréac, A.; Molnar, G.; Toupet, L.; Bousseksou, A.; Létard, J. F.; Matouzenko, G. S.

    2010-12-01

    Crystallographic, magnetic, and Raman investigations of the mononuclear [FeII(Hpy-DAPP)](BF4)2 complex are presented. Its particular feature is a two-step thermal spin conversion in spite of a unique symmetry-independent iron site per unit cell. The plateau around 140 K is associated with a symmetry breaking visible by the appearance of weak (0k0) k odd Bragg peaks. Symmetries of the high-temperature high-spin state and of the low-temperature low-spin state are both monoclinic P21/c , so that the symmetry breaking on the plateau is associated with a reentrant phase transition. It is discussed in relation with Ising-type microscopic models. At the plateau level, the two symmetry-independent molecules differ both by their spin state and the conformation (chair versus twist-boat) of one metallocycle. At low-temperature photoinduced phenomena have been investigated: a partial phototransformation [light-induced excited spin-state trapping (LIESST) effect] is observed under visible red irradiation. Raman spectroscopy shows that the molecular photoinduced state is the high-spin one. Nevertheless, as no macroscopic symmetry breaking is observed, the unique average cationic [FeII(Hpy-DAPP)] state of the unit cell is intermediate between pure low-spin and high-spin states and presents a conformational disorder for one metallocycle. Reverse-LIESST has also been evidenced using near infrared excitation. Thus, the mononuclear [Fe(Hpy-DAPP)](BF4)2 compound offers the opportunity to discuss the interplay between spin conversion, molecular conformational change, and ordering processes.

  20. A Comparison of Heart Rate States by Complexity Measures%基于复杂性测度的心率状态对比

    Institute of Scientific and Technical Information of China (English)

    王涛; 沈谦; 冯焕清

    2002-01-01

    本文介绍了近似熵(ApEn)和谱熵(SE)两种复杂性测度,研究了在两组静默(采用中国气功和Kundalini瑜珈练习方法)和正常状态下的心率复杂性.观察到两种状态下复杂度有明显差异,但两种状态下复杂性数值的大小关系对取决于不同的个体.研究结果进一步在心率变化的复杂性方面支持了关于在人体心率和自主调节间存在某种关联的看法,并提供了新的定量描述心率不同状态的方式和途径.%Two complexity measures, approximate entropy (ApEn) and spectral entropy (SE) were introduced and investigated on heart rate (HR) sequences recorded from healthy young adults by Peng C-K with specific traditional forms of Chinese Chi and Kundalini Yoga meditation techniques. According to these measurements, distinctions of complexity between premedication and medication were observed. However, conclusion as to which state is more complex is subject-dependent. The results supported the conjecture that meditation does not appear to be only a psychologically and physiologically quiescent (homeostatic) state as conventionally believed, and there are connections in terms of complexity between beat-to-beat heart rate dynamics and automatic regulation.

  1. Synthesis and characterizations of NiO nanoparticles via solid-state thermal decomposition of nickel(II) Schiff base complexes

    Science.gov (United States)

    Khalaji, Aliakbar Dehno; Das, Debasis

    2014-08-01

    To raise the need of new precursors in the synthesis of NiO nanoparticles, mononuclear nickel(II) Schiff base complexes, viz. Ni(salbn) and Ni(Me2-salpn), were employed as precursor in solid-state thermal decomposition. Structure, purity and morphology of these nanoparticles have been examined by Fourier transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy (TEM). TEM analysis reveals that the synthesized nanoparticles have cubic particles with an average diameter of around 5-15 nm. This method is simple, less costly, and fast and safe for production of NiO nanoparticles in industrial applications.

  2. [Efficiency of using vitamin-mineral complexes in the prevention of iron-deficiency states in athletes].

    Science.gov (United States)

    Zaĭtseva, I P

    2010-01-01

    Examinations of 49 athletes aged 18 to 22 years established that 2-week intake of vitamin-mineral complexes (VMC) caused a significant increase in the concentrations of iron, copper, and magnesium in plasma and blood corpuscles and a rise in the content of hemoglobin, red blood cells, and body vitamin C provision, and exercise performance during the positive balance of the above trace elements (TE), which is indicative of their deficiency in the body in summer. Supplementation of TE to diets showed that increasing the dose of minerals as components of VMC substantially reduced the percentage assimilation of iron, copper, and magnesium as constituents of preparations and increased fecal and urinary ME excretion.

  3. Vol. 33 - Compact State-Space Models for Complex Superconducting Radio-Frequency Structures Based on Model Order Reduction and Concatenation Methods

    CERN Document Server

    Flisgen, Thomas

    2015-01-01

    The modeling of large chains of superconducting cavities with couplers is a challeng- ing task in computational electrical engineering. The direct numerical treatment of these structures can easily lead to problems with more than ten million degrees of freedom. Problems of this complexity are typically solved with the help of parallel programs running on supercomputing infrastructures. However, these infrastructures are expensive to purchase, to operate, and to maintain. The aim of this thesis is to introduce and to validate an approach which allows for modeling large structures on a standard workstation. The novel technique is called State-Space Concatena- tions and is based on the decomposition of the complete structure into individual segments. The radio-frequency properties of the generated segments are described by a set of state-space equations which either emerge from analytical considera- tions or from numerical discretization schemes. The model order of these equations is reduced...

  4. Solid-state 51V MAS NMR spectroscopy determines component concentration and crystal phase in co-crystallised mixtures of vanadium complexes

    DEFF Research Database (Denmark)

    Nielsen, Ulla Gro; Hazell, Alan Charles; Skibsted, Jørgen Bengaard

    2010-01-01

    resonances are sensitive to intermolecular interactions specific to each crystal phase. The solid-state V-51 MAS NMR spectroscopic data show that the different phases do not co-precipitate but the concentration of the solute (which can be either 1 or 2) can vary. Thus co-crystallised mixtures of 1 and 2 can...... be classed as a molecular mixture capable of forming continuous solid solutions....... for the vanadium atoms of the two complexes mean that V-51 solution state and MAS NMR spectroscopy can be used to determine the concentration of 1 and 2 in bulk samples. Significantly, however, V-51 MAS NMR spectroscopy also reports on the identity of the crystal phase. This is possible because the isotropic V-51...

  5. A strong steric hindrance effect on ground state, excited state, and charge separated state properties of a CuI-diimine complex captured by X-ray transient absorption spectroscopy

    DEFF Research Database (Denmark)

    Huang, J.; Mara, M.W.; Stickrath, A.B.

    2014-01-01

    Photophysical and structural properties of a CuI diimine complex with very strong steric hindrance, [CuI(dppS)2]+ (dppS = 2,9-diphenyl-1,10-phenanthroline disulfonic acid disodium salt), are investigated by optical and X-ray transient absorption (OTA and XTA) spectroscopy. The bulky phenylsulfonic...... of metal complex/semiconductor NP hybrids but also provide guidance for designing efficient CuI diimine complexes with optimized structures for application in solar-to-electricity conversion. This journal is...

  6. Photo-Induced Spin-State Conversion in Solvated Transition Metal Complexes Probed via Time-Resolved Soft X-ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Huse, Nils; Kim, Tae Kyu; Jamula, Lindsey; McCusker, James K.; de Groot, Frank M. F.; Schoenlein, Robert W.

    2010-04-30

    Solution-phase photoinduced low-spin to high-spin conversion in the FeII polypyridyl complex [Fe(tren(py)3)]2+ (where tren(py)3 is tris(2-pyridylmethyliminoethyl)amine) has been studied via picosecond soft X-ray spectroscopy. Following 1A1 --> 1MLCT (metal-to-ligand charge transfer) excitation at 560 nm, changes in the iron L2- and L3-edges were observed concomitant with formation of the transient high-spin 5T2 state. Charge-transfer multiplet calculations coupled with data acquired on low-spin and high-spin model complexes revealed a reduction in ligand field splitting of 1 eV in the high-spin state relative to the singlet ground state. A significant reduction in orbital overlap between the central Fe-3d and the ligand N-2p orbitals was directly observed, consistent with the expected ca. 0.2 Angstrom increase in Fe-N bond length upon formation of the high-spin state. The overall occupancy of the Fe-3d orbitals remains constant upon spin crossover, suggesting that the reduction in sigma-donation is compensated by significant attenuation of pi-back-bonding in the metal-ligand interactions. These results demonstrate the feasibility and unique potential of time-resolved soft X-ray absorption spectroscopy to study ultrafast reactions in the liquid phase by directly probing the valence orbitals of first-row metals as well as lighter elements during the course of photochemical transformations.

  7. Structures of ceftazidime and its transition-state analogue in complex with AmpC beta-lactamase: Implications for resistance mutations and inhibitor design

    Energy Technology Data Exchange (ETDEWEB)

    Powers, R.A.; Caselli, E.; Focia, P.J.; Prati, F.; Shoichet, B.K.

    2010-03-08

    Third-generation cephalosporins are widely used {beta}-lactam antibiotics that resist hydrolysis by {beta}-lactamases. Recently, mutant {beta}-lactamases that rapidly inactivate these drugs have emerged. To investigate why third-generation cephalosporins are relatively stable to wild-type class C {beta}-lactamases and how mutant enzymes might overcome this, the structures of the class C {beta}-lactamase AmpC in complex with the third-generation cephalosporin ceftazidime and with a transition-state analogue of ceftazidime were determined by X-ray crystallography to 2.0 and 2.3 {angstrom} resolution, respectively. Comparison of the acyl-enzyme structures of ceftazidime and loracarbef, a {beta}-lactam substrate, reveals that the conformation of ceftazidime in the active site differs from that of substrates. Comparison of the structures of the acyl-enzyme intermediate and the transition-state analogue suggests that ceftazidime blocks formation of the tetrahedral transition state, explaining why it is an inhibitor of AmpC. Ceftazidime cannot adopt a conformation competent for catalysis due to steric clashes that would occur with conserved residues Val211 and Tyr221. The X-ray crystal structure of the mutant {beta}-lactamase GC1, which has improved activity against third-generation cephalosporins, suggests that a tandem tripeptide insertion in the {Omega} loop, which contains Val211, has caused a shift of this residue and also of Tyr221 that would allow ceftazidime and other third-generation cephalosporins to adopt a more catalytically competent conformation. These structural differences may explain the extended spectrum activity of GC1 against this class of cephalosporins. In addition, the complexed structure of the transition-state analogue inhibitor (K{sub i} 20 nM) with AmpC reveals potential opportunities for further inhibitor design.

  8. Trends in permanent pacemaker implantation in the United States from 1993 to 2009: increasing complexity of patients and procedures.

    Science.gov (United States)

    Greenspon, Arnold J; Patel, Jasmine D; Lau, Edmund; Ochoa, Jorge A; Frisch, Daniel R; Ho, Reginald T; Pavri, Behzad B; Kurtz, Steven M

    2012-10-16

    This study sought to define contemporary trends in permanent pacemaker use by analyzing a large national database. The Medicare National Coverage Determination for permanent pacemaker, which emphasized single-chamber pacing, has not changed significantly since 1985. We sought to define contemporary trends in permanent pacemaker use by analyzing a large national database. We queried the Nationwide Inpatient Sample to identify permanent pacemaker implants between 1993 and 2009 using the International Classification of Diseases-Ninth Revision-Clinical Modification procedure codes for dual-chamber (DDD), single-ventricular (VVI), single-atrial (AAI), or biventricular (BiV) devices. Annual permanent pacemaker implantation rates and patient demographics were analyzed. Between 1993 and 2009, 2.9 million patients received permanent pacemakers in the United States. Overall use increased by 55.6%. By 2009, DDD use increased from 62% to 82% (p pacemaker use fell from 36% to 14% (p = 0.01). Use of DDD devices was higher in urban, nonteaching hospitals (79%) compared with urban teaching hospitals (76%) and rural hospitals (72%). Patients with private insurance (83%) more commonly received DDD devices than Medicaid (79%) or Medicare (75%) recipients (p pacemakers in the United States. Although DDD device use is increasing, whereas single-chamber ventricular pacemaker use is decreasing. Patients are becoming older and have more medical comorbidities. These trends have important health care policy implications. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  9. Surface fuels quantification in forest plantations and remaining of atlantic forest in the “Brejo” region in Paraíba State, Brazil”

    Directory of Open Access Journals (Sweden)

    Patrícia Carneiro Souto

    2009-12-01

    Full Text Available Studies on the accumulation of combustible material in native forests and plantations are mainly important tool for estimating the risk of forest fires. This study aimed to determine the amount of combustible material in forest stands and in the remaining rain forest located in the municipality of Areia, in Brejo of Paraiba. The collection of combustible material was carried out in plots of 1m ², randomly selected areas. The fuel accumulated in the different areas were classified according to the physiological state of alive and dead. The largest amount of combustible material was obtained in the area of the Atlantic with 19.47 Mg ha-1. The amount of combustible material alive did not differ between the studied areas.

  10. The Northern triangle: relations between the United States, the EU and Russia A flexible and complex complementariness

    Directory of Open Access Journals (Sweden)

    Francesc Serra Massansalvador

    2005-05-01

    Full Text Available This article sets out to analyse the structural implications of the cooperation between the United States, the European Union and Russia, as well as the shape this cooperation assumes according to the area dealt with. At the beginning of this new century, the structureof the international system presents symptoms of variable geometry, in which the country that appears to be the hegemonic power in the area of security needs solid supports in order to exercise this hegemony. These supports will have to be sought not only at thestrategic level, but, above all, in such aspects as trade, control of international organisations and even the ideological arena, all of which are areas in which it would be difficult to exert hegemony through a unilateral approach.

  11. Intermolecular potential and rovibrational states of the H{sub 2}O-D{sub 2} complex

    Energy Technology Data Exchange (ETDEWEB)

    Avoird, Ad van der, E-mail: A.vanderAvoird@theochem.ru.nl [Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Scribano, Yohann [Laboratoire Interdisciplinaire Carnot de Bourgogne-UMR 5209, CNRS-Universite de Bourgogne, 9 Av. Alain Savary, B.P. 47870, F-21078 Dijon Cedex (France); Faure, Alexandre [UJF-Grenoble 1/CNRS, Institut de Planetologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble F-38041 (France); Weida, Miles J. [Daylight Solutions, 15378 Avenue of Science, San Diego, CA 92128 (United States); Fair, Joanna R. [Department of Radiology, MSC10 5530, 1 University of New Mexico, Albuquerque, NM 87131-0001 (United States); Nesbitt, David J. [JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0440 (United States)

    2012-05-03

    Graphical abstract: H{sub 2}O-D{sub 2} potential surface and pH{sub 2}O-oD{sub 2} ground state wave function, for planar geometries. Highlights: Black-Right-Pointing-Pointer The interaction between H{sub 2}O and H{sub 2} is of great astrophysical interest. Black-Right-Pointing-Pointer The rovibrational states of H{sub 2}O-D{sub 2} were computed on an ab initio potential surface. Black-Right-Pointing-Pointer Results are compared with the rovibrational states of H{sub 2}O-H{sub 2} computed recently. Black-Right-Pointing-Pointer We measured the high-resolution infrared spectrum of H{sub 2}O-D{sub 2} in the H{sub 2}O bend region. Black-Right-Pointing-Pointer Comparison with the calculations provides information on H{sub 2}O-H{sub 2} potential surface. - Abstract: A five-dimensional intermolecular potential for H{sub 2}O-D{sub 2} was obtained from the full nine-dimensional ab initio potential surface of Valiron et al. [P. Valiron, M. Wernli, A. Faure, L. Wiesenfeld, C. Rist, S. Kedzuch, J. Noga, J. Chem. Phys. 129 (2008) 134306] by averaging over the ground state vibrational wave functions of H{sub 2}O and D{sub 2}. On this five-dimensional potential with a well depth D{sub e} of 232.12 cm{sup -1} we calculated the bound rovibrational levels of H{sub 2}O-D{sub 2} for total angular momentum J = 0-3. The method used to compute the rovibrational levels is similar to a scattering approach-it involves a basis of coupled free rotor wave functions for the hindered internal rotations and the overall rotation of the dimer-while it uses a discrete variable representation of the intermolecular distance coordinate R. The basis was adapted to the permutation symmetry associated with the para/ortho (p/o) nature of both H{sub 2}O and D{sub 2}, as well as to inversion symmetry. As expected, the H{sub 2}O-D{sub 2} dimer is more strongly bound than its H{sub 2}O-H{sub 2} isotopologue [cf. A. van der Avoird, D.J. Nesbitt, J. Chem. Phys. 134 (2011) 044314], with dissociation energies D

  12. Mismatch negativity and P3a/reorienting complex in subjects with schizophrenia or at-risk mental state

    Directory of Open Access Journals (Sweden)

    Yuko eHiguchi

    2014-05-01

    Full Text Available Introduction: Shorter duration of untreated psychosis has been associated with better prognosis in patients with schizophrenia. In Introduction: In this study, we measured duration mismatch negativity (dMMN, P3a and reorienting negativity (RON in subjects with at-risk mental state (ARMS, patients with first-episode or chronic schizophrenia, and healthy volunteers. The main interest was to determine if these event-related potentials provide a biomarker associated with progression to overt schizophrenia in ARMS subjects.Methods: Seventeen ARMS subjects meeting the criteria of the Comprehensive Assessment of At-Risk Mental State, 38 patients with schizophrenia (19 first-episode and 19 chronic, and 19 healthy controls participated in the study. dMMN, P3a and RON were measured with an auditory odd-ball paradigm at baseline. Results: During the follow-up period (2.2 years, 4 out of the 19 ARMS subjects transitioned to schizophrenia (Converters while 15 did not (non-Converters. dMMN amplitudes of Converters were significantly smaller than those of non-Converters at frontal and central electrodes before onset of illness. dMMN amplitudes of non-Converters did not differ from those of healthy controls, while Converters showed significantly smaller dMMN amplitudes compared to control subjects. RON amplitudes were also reduced at frontal and central electrodes in subjects with schizophrenia, but not ARMS. Converter subjects tended to show smaller RON amplitudes compared to non-Converters. Conclusions: Our data confirm that diminished dMMN amplitudes provide a biomarker which is present before and after the development of psychosis. In this respect, RON amplitudes may also be useful, as suggested for the first time in this study.

  13. Pulse EPR, 55Mn-ENDOR and ELDOR-detected NMR of the S2-state of the oxygen evolving complex in photosystem II.

    Science.gov (United States)

    Kulik, Leonid; Epel, Boris; Messinger, Johannes; Lubitz, Wolfgang

    2005-06-01

    Pulse EPR, 55Mn-ENDOR and ELDOR-detected NMR experiments were performed on the S2-state of the oxygen-evolving complex from spinach Photosystem II. The novel technique of random acquisition in ENDOR was used to suppress heating artefacts. Our data unambiguously shows that four Mn ions have significant hyperfine coupling constants. Numerical simulation of the 55Mn-ENDOR spectrum allowed the determination of the principal values of the hyperfine interaction tensors for all four Mn ions of the oxygen-evolving complex. The results of our 55Mn-ENDOR experiments are in good agreement with previously published data [Peloquin JM et al. (2000) J Am Chem Soc 122: 10926-10942]. For the first time ELDOR-detected NMR was applied to the S2-state and revealed a broad peak that can be simulated numerically with the same parameters that were used for the simulation of the 55Mn-ENDOR spectrum. This provides strong independent support for the assigned hyperfine parameters.

  14. Comparison of Escherichia coli tRNAPhe in the free state, in the ternary complex and in the ribosomal A and P sites by chemical probing

    DEFF Research Database (Denmark)

    Douthwaite, S; Garrett, R A; Wagner, R

    1983-01-01

    with elongation factor EF-Tu and GTP and in the ribosomal A and P sites were compared. A special procedure was devised to monitor, exclusively, tRNA molecules in the aminoacylated state. In the free tRNA, the most reactive bases are confined to the A73-C-C-A sequence of the aminoacyl stem, the anticodon loop......tRNAPheE.coli was modified at accessible guanosine, cytidine, and adenosine residues using the chemical modification method described by Peattie and Gilbert [Proc. Natl Acad. Sci. USA, 77, 4679-4689 (1980)]. Modification characteristics of the tRNA in the free state, in the ternary complex......, the D-loop and the extra loop and the results correlate well with the three-dimensional structure of tRNAPheyeast determined by X-ray studies. The pattern of reactivity was not affected either by charging the tRNA with phenylalanine or by labelling the 3' terminus with pCp. In the ternary complex...

  15. A chelate-stabilized ruthenium(sigma-pyrrolato) complex: resolving ambiguities in nuclearity and coordination geometry through 1H PGSE and 31P solid-state NMR studies.

    Science.gov (United States)

    Foucault, Heather M; Bryce, David L; Fogg, Deryn E

    2006-12-11

    Reaction of RuCl2(PPh3)3 with LiNN' (NN' = 2-[(2,6-diisopropylphenyl)imino]pyrrolide) affords a single product, with the empirical formula RuCl[(2,6-iPr2C6H3)N=CHC4H3N](PPh3)2. We identify this species as a sigma-pyrrolato complex, [Ru(NN')(PPh3)2]2(mu-Cl)2 (3b), rather than mononuclear RuCl(NN')(PPh3)2 (3a), on the basis of detailed 1D and 2D NMR characterization in solution and in the solid state. Retention of the chelating, sigma-bound iminopyrrolato unit within 3b, despite the presence of labile (dative) chloride and PPh3 donors, indicates that the chelate effect is sufficient to inhibit sigma --> pi isomerization of 3b to a piano-stool, pi-pyrrolato structure. 2D COSY, SECSY, and J-resolved solid-state 31P NMR experiments confirm that the PPh3 ligands on each metal center are magnetically and crystallographically inequivalent, and 31P CP/MAS NMR experiments reveal the largest 99Ru-31P spin-spin coupling constant (1J(99Ru,31P) = 244 +/- 20 Hz) yet measured. Finally, 31P dipolar-chemical shift spectroscopy is applied to determine benchmark phosphorus chemical shift tensors for phosphine ligands in hexacoordinate ruthenium complexes.

  16. Molecular and Growth-Based Drug Susceptibility Testing of Mycobacterium tuberculosis Complex for Ethambutol Resistance in the United States

    Directory of Open Access Journals (Sweden)

    Mitchell A. Yakrus

    2016-01-01

    Full Text Available Ethambutol (EMB is used as a part of drug regimens for treatment of tuberculosis (TB. Susceptibility of Mycobacterium tuberculosis complex (MTBC isolates to EMB can be discerned by DNA sequencing to detect mutations in the embB gene associated with resistance. US Public Health Laboratories (PHL primarily use growth-based drug susceptibility test (DST methods to determine EMB resistance. The Centers for Disease Control and Prevention (CDC provides a service for molecular detection of drug resistance (MDDR by DNA sequencing and concurrent growth-based DST using agar proportion. PHL and CDC test results were compared for 211 MTBC samples submitted to CDC from September 2009 through February 2011. Concordance between growth-based DST results from PHL and CDC was 88.2%. A growth-based comparison of 39 samples, where an embB mutation associated with EMB resistance was detected, revealed a higher percentage of EMB resistance by CDC (84.6% than by PHL (59.0% which was significant (P value = 0.002. Discordance between all growth-based test results from PHL and CDC was also significant (P value = 0.003. Most discordance was linked to false susceptibility using the BACTEC™ MGIT™ 960 (MGIT growth-based system. Our analysis supports coalescing growth-based and molecular results for an informed interpretation of potential EMB resistance.

  17. Xanthan Exopolysaccharide: Cu(2+) Complexes Affected from the pH-Dependent Conformational State; Implications for Environmentally Relevant Biopolymers.

    Science.gov (United States)

    Causse, Benjamin; Spadini, Lorenzo; Sarret, Géraldine; Faure, Adeline; Travelet, Christophe; Madern, Dominique; Delolme, Cécile

    2016-04-05

    The conformational impact of environmental biopolymers on metal sorption was studied through Cu sorption on xanthan. The apparent Cu(2+) complexation constant (logK; Cu(2+) + L(-) ↔ CuL(+)) decreased from 2.9 ± 0.1 at pH 3.5 to 2.5 ± 0.1 at pH 5.5 (ionic strength I = 0.1). This behavior is in apparent contradiction with basic thermodynamics, as usually the higher the pH the more cations bind. Our combined titration, circular dichroism and dynamic light scattering study indicated that the change observed in Cu bond strength relates to a conformational change of the structure of xanthan, which generates more chelating sites at pH 3.5 than at pH 5.5. This hypothesis was validated by the fact that the Cu sorption constants on xanthan were always higher than those measured on a mixture of pyruvic and glucuronic acids (logK = 2.2), which are the two constitutive ligands present in the xanthan monomer. This study shows the role of the structural conformation of natural biopolymers in metal bond strength. This finding may help to better predict the fate of Cu and other metals in acidic environmental settings such as aquatic media affected by acid mine drainage, as well as peats and acidic soils, and to better define optimal conditions for bioremediation processes.

  18. End State Condition Report for Materials and Fuels Complex Facilities MFC-799, 799A, and 770C

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mecham

    2010-10-01

    The Materials and Fuels Complex (MFC) facilities MFC-799, “Sodium Processing Facility” (a single building consisting of two areas: the Sodium Process Area and the Carbonate Process Area); MFC-799A, “Caustic Storage Area;” and MFC-770C, “Nuclear Calibration Laboratory,” have been declared excess to future Department of Energy (DOE) Office of Nuclear Energy(NE) mission requirements. Transfer of these facilities from NE to the DOE Office of Environmental Management (EM), and an associated schedule for doing so, have been agreed upon by the two offices. This report documents the completion of pre-transfer stabilization actions, as identified in DOE Guide 430.1-5, “Transition Implementation Guide,” for buildings MFC-799/799A and 770C, and indicates that these facilities are ready for transfer from NE to EM. The facilities are in a known, safe condition and information is provided to support efficient decommissioning and demolition (D&D) planning while minimizing the possibility of encountering unforeseen circumstances during the D&D activities.

  19. Solid state molecular device based on a rhenium(I) polypyridyl complex immobilized on TiO2 films.

    Science.gov (United States)

    Patrocinio, Antonio Otavio T; Frin, Karina P M; Murakami Iha, Neyde Y

    2013-05-20

    The photochemical and photophysical behaviors of fac-[Re(CO)3(phen)(trans-stpyCOOH)](+) (phen = 1,10-phenanthroline, trans-stpyCOOH = 4-[trans-(pyridin-4-yl-vinyl)]benzoic acid) in acetonitrile solution and adsorbed on a TiO2 film have been investigated. The trans-to-cis photoisomerization at 404 nm irradiation of coordinated stpyCOOH occurs efficiently in fluid solution as shown by quantum yield determined spectrophotometrically (Φ(UV-vis) = 0.37 ± 0.04) and, more accurately, by (1)H NMR (Φ(NMR) = 0.48 ± 0.04), following the photoproduct signals in the distinct region of the reactant. For the first time, the trans-to-cis isomerization is also reported for the complex adsorbed on the TiO2 surface (Φ(UV-vis) = 0.23 ± 0.03). The photoproduct, fac-[Re(CO)3(phen)(cis-stpyCOOH)](+), is emissive in acetonitrile (ϕ = 0.032), but its radiative decay is highly quenched on the oxide surface by electron photoinjection into the semiconductor, leading to an increasing photocurrent as the trans-to-cis isomerization takes place. Therefore, the photoinduced trans-to-cis isomerization of coordinated ligand immobilized on TiO2 films acts as a trigger for the electron injection process. This system exemplifies the use of photoinduced molecular motion to yield electrical current, which can be used as a "proof of concept" for molecular machines/devices.