WorldWideScience

Sample records for group c4 artificial

  1. Antifungal activities of pradimicin derivatives modified at C4'-amino group.

    Science.gov (United States)

    Kamachi, H; Okuyama, S; Hirano, M; Masuyoshi, S; Konishi, M; Oki, T

    1993-08-01

    In order to explore potent derivatives of pradimicins (PRMs), modification of their C4'-amino group was carried out. 4'-N-Cyano (1,2), 4'-deamino-4'-nitroguanidino (4), 4'-deamino-4'-ureido (7-9) and 4'-deamino-4'-thioureido (10) derivatives were synthesized by trimethylsilylation of PRMs A and C, followed by condensation with appropriate reagents. 4'-Deamino-4'-guanidino (5) and 4'-deamino-4'-amidino (6) derivatives were synthesized by catalytic hydrogenation of 4 and 2, respectively. 4'-N-Nitroso derivative 3 was prepared by treatment of PRM A with nitrous acid. Among these compounds, the 4'-N-cyano derivative of PRM C (2) exhibited in vitro and in vivo antifungal activities comparable to the parent compounds together with good water-solubility.

  2. Conserved patterns hidden within group A Streptococcus M protein hypervariability recognize human C4b-binding protein

    Energy Technology Data Exchange (ETDEWEB)

    Buffalo, Cosmo Z.; Bahn-Suh, Adrian J.; Hirakis, Sophia P.; Biswas, Tapan; Amaro, Rommie E.; Nizet, Victor; Ghosh, Partho

    2016-09-05

    No vaccine exists against group A Streptococcus (GAS), a leading cause of worldwide morbidity and mortality. A severe hurdle is the hypervariability of its major antigen, the M protein, with >200 different M types known. Neutralizing antibodies typically recognize M protein hypervariable regions (HVRs) and confer narrow protection. In stark contrast, human C4b-binding protein (C4BP), which is recruited to the GAS surface to block phagocytic killing, interacts with a remarkably large number of M protein HVRs (apparently ~90%). Such broad recognition is rare, and we discovered a unique mechanism for this through the structure determination of four sequence-diverse M proteins in complexes with C4BP. The structures revealed a uniform and tolerant ‘reading head’ in C4BP, which detected conserved sequence patterns hidden within hypervariability. Our results open up possibilities for rational therapies that target the M–C4BP interaction, and also inform a path towards vaccine design.

  3. GRASS SPECIES FROM C-4 CARBON FIXATION GROUP: POLISH EXPERIMENT WITH A NOVEL ENERGY AND FORAGE PURPOSES CROP

    Directory of Open Access Journals (Sweden)

    Włodzimierz Majtkowski

    2010-02-01

    Full Text Available Experiment was conducted during four years 2003-2006. Materials used were three genus grass species of C-4 photosynthesis: Andropogon gerardi Vitman, Panicum virgatum L. and Miscanthus sacchariflorus (Maxim. Hack. Plants were planted at spring 1998. Agrotechnical part of experiment was conducted in Botanical Garden of Plant Breeding Acclimatization Institute in Bydgoszcz and analytical part in Department of Animal Nutrition and Feed Management, Faculty of Animal Breeding and Biology of University of Technology and Life Science in Bydgoszcz. Forage from grass C-4 photosynthesis were material of good ensilage suitability. High structural carbohydrates (NDF, ADF contents in tested forage dry matter suggest ensilage at early phases of plant development. Above results suggest to possibility of usage of forage from grass C-4 carbon fixation group for animal feeding purposes. C-4 grass forage should be recognized as a supplementary source of green matter in periods of insufficient access to traditional silage sources.

  4. Towards Detecting Group Identities in Complex Artificial Societies

    DEFF Research Database (Denmark)

    Grappiolo, Corrado; Yannakakis, Georgios N.

    2012-01-01

    This paper presents a framework for modelling group struc- tures and dynamics in both artificial societies and human-populated vir- tual environments such as computer games. The group modelling (GM) framework proposed focuses on the detection of existing, pre-defined group structures and is compo......This paper presents a framework for modelling group struc- tures and dynamics in both artificial societies and human-populated vir- tual environments such as computer games. The group modelling (GM) framework proposed focuses on the detection of existing, pre-defined group structures...

  5. Artificial Evolution for the Detection of Group Identities in Complex Artificial Societies

    DEFF Research Database (Denmark)

    Grappiolo, Corrado; Togelius, Julian; Yannakakis, Georgios N.

    2013-01-01

    This paper aims at detecting the presence of group structures in complex artificial societies by solely observing and analysing the interactions occurring among the artificial agents. Our approach combines: (1) an unsupervised method for clustering interactions into two possible classes, namely in......- group and out-group, (2) reinforcement learning for deriving the existing levels of collaboration within the society, and (3) an evolutionary algorithm for the detection of group structures and the assignment of group identities to the agents. Under a case study of static societies — i.e. the agents do...... not evolve their social preferences — where agents interact with each other by means of the Ultimatum Game, our approach proves to be successful for small-sized social networks independently on the underlying social structure of the society; promising results are also registered for mid-size societies....

  6. Hydrogen peroxide elimination from C4a-hydroperoxyflavin in a flavoprotein oxidase occurs through a single proton transfer from flavin N5 to a peroxide leaving group.

    Science.gov (United States)

    Sucharitakul, Jeerus; Wongnate, Thanyaporn; Chaiyen, Pimchai

    2011-05-13

    C4a-hydroperoxyflavin is found commonly in the reactions of flavin-dependent monooxygenases, in which it plays a key role as an intermediate that incorporates an oxygen atom into substrates. Only recently has evidence for its involvement in the reactions of flavoprotein oxidases been reported. Previous studies of pyranose 2-oxidase (P2O), an enzyme catalyzing the oxidation of pyranoses using oxygen as an electron acceptor to generate oxidized sugars and hydrogen peroxide (H(2)O(2)), have shown that C4a-hydroperoxyflavin forms in P2O reactions before it eliminates H(2)O(2) as a product (Sucharitakul, J., Prongjit, M., Haltrich, D., and Chaiyen, P. (2008) Biochemistry 47, 8485-8490). In this report, the solvent kinetic isotope effects (SKIE) on the reaction of reduced P2O with oxygen were investigated using transient kinetics. Our results showed that D(2)O has a negligible effect on the formation of C4a-hydroperoxyflavin. The ensuing step of H(2)O(2) elimination from C4a-hydroperoxyflavin was shown to be modulated by an SKIE of 2.8 ± 0.2, and a proton inventory analysis of this step indicates a linear plot. These data suggest that a single-proton transfer process causes SKIE at the H(2)O(2) elimination step. Double and single mixing stopped-flow experiments performed in H(2)O buffer revealed that reduced flavin specifically labeled with deuterium at the flavin N5 position generated kinetic isotope effects similar to those found with experiments performed with the enzyme pre-equilibrated in D(2)O buffer. This suggests that the proton at the flavin N5 position is responsible for the SKIE and is the proton-in-flight that is transferred during the transition state. The mechanism of H(2)O(2) elimination from C4a-hydroperoxyflavin is consistent with a single proton transfer from the flavin N5 to the peroxide leaving group, possibly via the formation of an intramolecular hydrogen bridge.

  7. Effects of different elevated CO2 concentrations on chlorophyll contents, gas exchange, water use efficiency, and PSII activity on C3 and C4 cereal crops in a closed artificial ecosystem.

    Science.gov (United States)

    Wang, Minjuan; Xie, Beizhen; Fu, Yuming; Dong, Chen; Hui, Liu; Guanghui, Liu; Liu, Hong

    2015-12-01

    Although terrestrial CO2 concentrations [CO2] are not expected to reach 1000 μmol mol(-1) (or ppm) for many decades, CO2 levels in closed systems such as growth chambers and greenhouses can easily exceed this concentration. CO2 levels in life support systems (LSS) in space can exceed 10,000 ppm (1 %). In order to understand how photosynthesis in C4 plants may respond to elevated CO2, it is necessary to determine if leaves of closed artificial ecosystem grown plants have a fully developed C4 photosynthetic apparatus, and whether or not photosynthesis in these leaves is more responsive to elevated [CO2] than leaves of C3 plants. To address this issue, we evaluated the response of gas exchange, water use efficiency, and photosynthetic efficiency of PSII by soybean (Glycine max (L.) Merr., 'Heihe35') of a typical C3 plant and maize (Zea mays L., 'Susheng') of C4 plant under four CO2 concentrations (500, 1000, 3000, and 5000 ppm), which were grown under controlled environmental conditions of Lunar Palace 1. The results showed that photosynthetic pigment by the C3 plants of soybean was more sensitive to elevated [CO2] below 3000 ppm than the C4 plants of maize. Elevated [CO2] to 1000 ppm induced a higher initial photosynthetic rate, while super-elevated [CO2] appeared to negate such initial growth promotion for C3 plants. The C4 plant had the highest ETR, φPSII, and qP under 500-3000 ppm [CO2], but then decreased substantially at 5000 ppm [CO2] for both species. Therefore, photosynthetic down-regulation and a decrease in photosynthetic electron transport occurred by both species in response to super-elevated [CO2] at 3000 and 5000 ppm. Accordingly, plants can be selected for and adapt to the efficient use of elevated CO2 concentration in LSS.

  8. Cyclodextrin derivatives with cyanohydrin and carboxylate groups as artificial glycosidases

    DEFF Research Database (Denmark)

    Bols, Mikael; Ortega-Caballero, Fernando

    2006-01-01

    Two cyclodextrin derivatives (1 and 2) were prepared in an attempt to create glycosidase mimics with a general acid catalyst and a nucleophilic carboxylate group. The catalysts 1 and 2 were found to catalyse the hydrolysis of 4-nitrophenyl beta-D-glucopyranoside at pH 8.0, but rapidly underwent...

  9. C4ISR Involvement with the Distributed Engineering Plant (DEP)

    National Research Council Canada - National Science Library

    Le, BeEm V

    2001-01-01

    ...). The DEP Battle Group Interoperability Test (BGIT) was a combination of several Navy laboratories in which command, control, communications, computers, intelligence, surveillance, and reconnaissance (C4ISR...

  10. A modern artificial intelligence Playware art tool for psychological testing of group dynamics

    DEFF Research Database (Denmark)

    Pagliarini, Luigi; Lund, Henrik Hautop

    2015-01-01

    We describe an artistic method used for the psychological analysis of group dynamics. The design of the artistic system, which mediates group dynamics, emerges from our studies of modular Playware and remixing Playware. Inspired from remixing modular Playware, where users remix samples in the form...... and the psychological findings. We describe the modern artificial intelligence implementation of this instrument. Between an art piece and a psychological test, at a first cognitive analysis, it seems to be a promising research tool. In the discussion we speculate about potential industrial applications, as well....

  11. Artificial intelligence on the identification of risk groups for osteoporosis, a general review.

    Science.gov (United States)

    Cruz, Agnaldo S; Lins, Hertz C; Medeiros, Ricardo V A; Filho, José M F; da Silva, Sandro G

    2018-01-29

    The goal of this paper is to present a critical review on the main systems that use artificial intelligence to identify groups at risk for osteoporosis or fractures. The systems considered for this study were those that fulfilled the following requirements: range of coverage in diagnosis, low cost and capability to identify more significant somatic factors. A bibliographic research was done in the databases, PubMed, IEEExplorer Latin American and Caribbean Center on Health Sciences Information (LILACS), Medical Literature Analysis and Retrieval System Online (MEDLINE), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus, Web of Science, and Science Direct searching the terms "Neural Network", "Osteoporosis Machine Learning" and "Osteoporosis Neural Network". Studies with titles not directly related to the research topic and older data that reported repeated strategies were excluded. The search was carried out with the descriptors in German, Spanish, French, Italian, Mandarin, Portuguese and English; but only studies written in English were found to meet the established criteria. Articles covering the period 2000-2017 were selected; however, articles prior to this period with great relevance were included in this study. Based on the collected research, it was identified that there are several methods in the use of artificial intelligence to help the screening of risk groups of osteoporosis or fractures. However, such systems were limited to a specific ethnic group, gender or age. For future research, new challenges are presented. It is necessary to develop research with the unification of different databases and grouping of the various attributes and clinical factors, in order to reach a greater comprehensiveness in the identification of risk groups of osteoporosis. For this purpose, the use of any predictive tool should be performed in different populations with greater participation of male patients and inclusion of a larger age range for the

  12. A novel preformulation tool to group microcrystalline celluloses using artificial neural network and data clustering.

    Science.gov (United States)

    Soh, Josephine L P; Chen, Fei; Liew, Celine V; Shi, Daming; Heng, Paul W S

    2004-12-01

    To group microcrystalline celluloses (MCCs) using a combination of artificial neural network (ANN) and data clustering. Radial basis function (RBF) network was used to model the torque measurements of the various MCCs. Output from the RBF network was used to group the MCCs using a data clustering technique known as discrete incremental clustering (DIC). Rheological or torque profiles of various MCCs at different combinations of mixing time and water:MCC ratios were obtained using mixer torque rheometry (MTR). Correlation analysis was performed on the derived torque parameter Torque(max) and physical properties of the MCCs. Depending on the leniency of the predefined threshold parameters, the 11 MCCs can be assigned into 2 or 3 groups. Grouping results were also able to identify bulk and tapped densities as major factors governing water-MCC interaction. MCCs differed in their water retentive capacities whereby the denser Avicel PH 301 and PH 302 were more sensitive to the added water. An objective grouping of MCCs can be achieved with a combination of ANN and DIC. This aids in the preliminary assessment of new or unknown MCCs. Key properties that control the performance of MCCs in their interactions with water can be discovered.

  13. Multiple regression analyses in artificial-grammar learning: the importance of control groups.

    Science.gov (United States)

    Lotz, Anja; Kinder, Annette; Lachnit, Harald

    2009-03-01

    In artificial-grammar learning, it is crucial to ensure that above-chance performance in the test stage is due to learning in the training stage but not due to judgemental biases. Here we argue that multiple regression analysis can be successfully combined with the use of control groups to assess whether participants were able to transfer knowledge acquired during training when making judgements about test stimuli. We compared the regression weights of judgements in a transfer condition (training and test strings were constructed by the same grammar but with different letters) with those in a control condition. Predictors were identical in both conditions-judgements of control participants were treated as if they were based on knowledge gained in a standard training stage. The results of this experiment as well as reanalyses of a former study support the usefulness of our approach.

  14. The application of artificial intelligence for the identification of the maceral groups and mineral components of coal

    Science.gov (United States)

    Mlynarczuk, Mariusz; Skiba, Marta

    2017-06-01

    The correct and consistent identification of the petrographic properties of coal is an important issue for researchers in the fields of mining and geology. As part of the study described in this paper, investigations concerning the application of artificial intelligence methods for the identification of the aforementioned characteristics were carried out. The methods in question were used to identify the maceral groups of coal, i.e. vitrinite, inertinite, and liptinite. Additionally, an attempt was made to identify some non-organic minerals. The analyses were performed using pattern recognition techniques (NN, kNN), as well as artificial neural network techniques (a multilayer perceptron - MLP). The classification process was carried out using microscopy images of polished sections of coals. A multidimensional feature space was defined, which made it possible to classify the discussed structures automatically, based on the methods of pattern recognition and algorithms of the artificial neural networks. Also, from the study we assessed the impact of the parameters for which the applied methods proved effective upon the final outcome of the classification procedure. The result of the analyses was a high percentage (over 97%) of correct classifications of maceral groups and mineral components. The paper discusses also an attempt to analyze particular macerals of the inertinite group. It was demonstrated that using artificial neural networks to this end makes it possible to classify the macerals properly in over 91% of cases. Thus, it was proved that artificial intelligence methods can be successfully applied for the identification of selected petrographic features of coal.

  15. Engineering C4 photosynthetic regulatory networks.

    Science.gov (United States)

    Weissmann, Sarit; Brutnell, Thomas P

    2012-06-01

    C4 photosynthesis is a complex metabolic pathway responsible for carbon fixation in major feed, food and bioenergy crops. Although many enzymes driving this pathway have been identified, regulatory mechanisms underlying this system remain elusive. C4 photosynthesis contributes to photosynthetic efficiency in major bioenergy crops such as sugarcane, Miscanthus, switchgrass, maize and sorghum, and international efforts are underway to engineer C4 photosynthesis into C3 crops. A fundamental understanding of the C4 network is thus needed. New experimental and informatics methods can facilitate the accumulation and analysis of high-throughput data to define components of the C4 system. The use of new model plants, closely related to C4 crops, will also contribute to our understanding of the mechanisms that regulate this complex and important pathway. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Functional groupings and food web of an artificial reef used for sea cucumber aquaculture in northern China

    Science.gov (United States)

    Xu, Qinzeng; Zhang, Libin; Zhang, Tao; Zhang, Xuelei; Yang, Hongsheng

    2017-01-01

    Artificial reef is considered as a useful tool to remodel habitats in coastal and estuarine area. Some artificial reefs (ARs) were conducted in Shandong Peninsula for sea cucumber Apostichopus japonicus integrated multi-trophic aquaculture (IMTA). Little is known about the main feeding type and food resources of living organisms in this IMTA ecosystem. Neither is the information about other animals competing food with A. japonicus. Functional group (FG) and their food resources of mobile organisms and epifauna in ARs area were investigated. There were three types of food resources and five FGs within two trophic levels in studied area. Particle organic matter (POM), seaweed detritus and sediment were considered to be the main food resources. The first three FGs were primary consumers and were mainly epifauna, while the other two FGs were secondary consumers. FG 1 species were filter feeders, and group 2 was all deposit feeders and A. japonicus was in this group. FG 2 contained few species and this indicated that A. japonicus had few food competitors. FG 3 contained most epifauna species which were detritus feeders and this result implied that the artificial oyster shell reed can retain detritus effectively. The food sources of group 4 were complex. Species of group 5, mostly fish, occupied the top trophic level and fed primarily on species of FG 1 and FG 2. This kind of ARs can retain detritus effectively and provide suitable habitat to epifauna and surrounding natural fauna community.

  17. ISLSCP II C4 Vegetation Percentage

    Data.gov (United States)

    National Aeronautics and Space Administration — The photosynthetic composition (C3 or C4) of vegetation on the land surface is essential for accurate simulations of biosphere-atmosphere exchanges of carbon, water,...

  18. ISLSCP II C4 Vegetation Percentage

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The photosynthetic composition (C3 or C4) of vegetation on the land surface is essential for accurate simulations of biosphere-atmosphere exchanges of...

  19. Prediction of enthalpy of fusion of pure compounds using an Artificial Neural Network-Group Contribution method

    Energy Technology Data Exchange (ETDEWEB)

    Gharagheizi, Farhad, E-mail: fghara@ut.ac.ir [Saman Energy Giti Co., Postal Code 3331619636,Tehran (Iran, Islamic Republic of); Salehi, Gholam Reza [Islamic Azad University Nowshahr Branch, Nowshahr (Iran, Islamic Republic of)

    2011-07-10

    Highlights: {yields} An Artificial Neural Network-Group Contribution method is presented for prediction of enthalpy of fusion of pure compounds at their normal melting point. {yields} Validity of the model is confirmed using a large evaluated data set containing 4157 pure compounds. {yields} The average percent error of the model is equal to 2.65% in comparison with the experimental data. - Abstract: In this work, the Artificial Neural Network-Group Contribution (ANN-GC) method is applied to estimate the enthalpy of fusion of pure chemical compounds at their normal melting point. 4157 pure compounds from various chemical families are investigated to propose a comprehensive and predictive model. The obtained results show the Squared Correlation Coefficient (R{sup 2}) of 0.999, Root Mean Square Error of 0.82 kJ/mol, and average absolute deviation lower than 2.65% for the estimated properties from existing experimental values.

  20. C# 4.0 in a Nutshell

    CERN Document Server

    Albahari, Joseph

    2010-01-01

    What people are saying about C# 4.0 in a Nutshell "C# 4.0 in a Nutshell is one of the few books I keep on my desk as a quick reference. It is a book I recommend."--Scott Guthrie, Corporate Vice President, .NET Developer Platform, Microsoft Corporation "A must-read for a concise but thorough examination of the parallel programming features in the .NET Framework 4."--Stephen Toub, Parallel Computing Platform Program Manager, Microsoft "This wonderful book is a great reference for developers of all levels."-- Chris Burrows, C# Compiler Team, Microsoft When you have questions about how to u

  1. A tailored biocatalyst achieved by the rational anchoring of imidazole groups on a natural polymer: furnishing a potential artificial nuclease by sustainable materials engineering.

    Science.gov (United States)

    Ferreira, José G L; Grein-Iankovski, Aline; Oliveira, Marco A S; Simas-Tosin, Fernanda F; Riegel-Vidotti, Izabel C; Orth, Elisa S

    2015-04-11

    Foreseeing the development of artificial enzymes by sustainable materials engineering, we rationally anchored reactive imidazole groups on gum arabic, a natural biocompatible polymer. The tailored biocatalyst GAIMZ demonstrated catalytic activity (>10(5)-fold) in dephosphorylation reactions with recyclable features and was effective in cleaving plasmid DNA, comprising a potential artificial nuclease.

  2. Enhancing drought tolerance in C(4) crops.

    Science.gov (United States)

    Lopes, Marta S; Araus, Jose Luis; van Heerden, Philippus D R; Foyer, Christine H

    2011-05-01

    Adaptation to abiotic stresses is a quantitative trait controlled by many different genes. Enhancing the tolerance of crop plants to abiotic stresses such as drought has therefore proved to be somewhat elusive in terms of plant breeding. While many C(4) species have significant agronomic importance, most of the research effort on improving drought tolerance has focused on maize. Ideally, drought tolerance has to be achieved without penalties in yield potential. Possibilities for success in this regard are highlighted by studies on maize hybrids performed over the last 70 years that have demonstrated that yield potential and enhanced stress tolerance are associated traits. However, while our understanding of the molecular mechanisms that enable plants to tolerate drought has increased considerably in recent years, there have been relatively few applications of DNA marker technologies in practical C(4) breeding programmes for improved stress tolerance. Moreover, until recently, targeted approaches to drought tolerance have concentrated largely on shoot parameters, particularly those associated with photosynthesis and stay green phenotypes, rather than on root traits such as soil moisture capture for transpiration, root architecture, and improvement of effective use of water. These root traits are now increasingly considered as important targets for yield improvement in C(4) plants under drought stress. Similarly, the molecular mechanisms underpinning heterosis have considerable potential for exploitation in enhancing drought stress tolerance. While current evidence points to the crucial importance of root traits in drought tolerance in C(4) plants, shoot traits may also be important in maintaining high yields during drought.

  3. On the smell of Composition C-4.

    Science.gov (United States)

    Kranz, William; Kitts, Kelley; Strange, Nicholas; Cummins, Joshua; Lotspeich, Erica; Goodpaster, John

    2014-03-01

    In efforts to locate hidden explosives, humans have had few allies as valuable as the explosives-detecting canine. The unrivaled sensitivity and selectivity of the canine nose have combined to make these animals an attractive choice for law enforcement, military, and private security applications. Although the efficacy of trained detector dogs is well-established, the question of which chemical compounds are responsible for causing a dog to recognize a particular odor and alert to it remains a subject of debate for several explosive formulations--including, perhaps most notably, Composition C-4. Previous studies have indicated that cyclohexanone, 2,3-dimethyl-2,3-dinitrobutane, and 2-ethyl-1-hexanol are the chemicals that may cause canines to alert to C-4. This has led to the suggestion that these substances could be used as a substitute for genuine C-4 in the training, testing, and maintenance of explosives-detecting canines. In this paper, we present an alternative view. Using gas chromatography-mass spectrometry with solid phase microextraction as a pre-concentration technique, we have discovered that 2-ethyl-1-hexanol off-gasses not only from C-4, but also from benign sources, such as the common plasticizers bis(2-ethylhexyl)adipate, bis(2-ethylhexyl)sebacate, and bis(2-ethylhexyl)phthalate; as well as several plasticized items common to our everyday world, including PVC tile, PVC pipe, electrical tape, and credit cards. This observation may potentially discourage the use of 2-ethyl-1-hexanol for training purposes. We also present the results of our own canine field trials focused on the detection of C-4. Through the use of contingency tables and statistical testing, we demonstrate the failure of trained law enforcement dogs in our study to respond in any significant way to these potential odor compounds. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. ARTIFICIAL NEURAL NETWORK BASED METHOD OF ASSESSMENT OF STUDENTS` FOREIGN LANGUAGE COMPETENCE BY THE GROUP OF EXPERTS

    Directory of Open Access Journals (Sweden)

    Olha V. Zastelo

    2015-09-01

    Full Text Available In this article the method of the integral assessment of the level of students` foreign language communicative competence by the group of experts through the complex test in a foreign language is considered. The use of mathematical methods and modern specialized software during complex testing of students significantly improves the expert methods, particularly in the direction of increasing the reliability of the assessment. Capitalizing analytical software environment realizes the simulation of non-linear generalizations based on artificial neural networks, which increases the accuracy of the estimate and allows further efficient use of the competent experts` experience gained in the model.

  5. Crystal structures of Er4Ni13C4 and UW4C4

    International Nuclear Information System (INIS)

    Khalili, M.M.; Bodak, O.I.; Marusin, E.P.; Pecharskaya, A.O.

    1990-01-01

    Crystal structures of Er 4 Ni 13 C 4 (1) (sp.gr. Cmmm, a=1.1975(4), b=1.1694(3), c=0.3856(1) nm, Z=2) and UW 4 C 4 (2) (sp.gr. P4/m, a=0.8328(8), c=0.31345(9) nm, Z=2), relating to new types are determined. Structural type (1) is a derivative of La 2 Ni 5 C 3 structure, structural type (2) is close to UCr 4 C 4 structure

  6. C4 cycles: past, present, and future research on C4 photosynthesis.

    Science.gov (United States)

    Langdale, Jane A

    2011-11-01

    In the late 1960s, a vibrant new research field was ignited by the discovery that instead of fixing CO(2) into a C(3) compound, some plants initially fix CO(2) into a four-carbon (C(4)) compound. The term C(4) photosynthesis was born. In the 20 years that followed, physiologists, biochemists, and molecular and developmental biologists grappled to understand how the C(4) photosynthetic pathway was partitioned between two morphologically distinct cell types in the leaf. By the early 1990s, much was known about C(4) biochemistry, the types of leaf anatomy that facilitated the pathway, and the patterns of gene expression that underpinned the biochemistry. However, virtually nothing was known about how the pathway was regulated. It should have been an exciting time, but many of the original researchers were approaching retirement, C(4) plants were proving recalcitrant to genetic manipulation, and whole-genome sequences were not even a dream. In combination, these factors led to reduced funding and the failure to attract young people into the field; the endgame seemed to be underway. But over the last 5 years, there has been a resurgence of interest and funding, not least because of ambitious multinational projects that aim to increase crop yields by introducing C(4) traits into C(3) plants. Combined with new technologies, this renewed interest has resulted in the development of more sophisticated approaches toward understanding how the C(4) pathway evolved, how it is regulated, and how it might be manipulated. The extent of this resurgence is manifest by the publication in 2011 of more than 650 pages of reviews on different aspects of C(4). Here, I provide an overview of our current understanding, the questions that are being addressed, and the issues that lie ahead.

  7. Hierarchical and non-hierarchical clustering and artificial neural networks for thechracterization of groups of feedlot-finished male cattle

    Directory of Open Access Journals (Sweden)

    Wignez Henrique

    2015-03-01

    Full Text Available The individual experimental results of 1,393 feedlot-finished cattle of different genetic groups obtained at different research institutions were collected. Exploratory multivariate hierarchical analysis was applied, which permitted the division of cattle into seven groups containing animals with similar performance patterns. The following variables were studied: weight of the animal at feedlot entry and exit, concentrate percentage, time spent in the feedlot, dry matter intake, weight gain, and feed efficiency. The data were submitted to non-hierarchical k-means cluster analysis, which revealed that all traits should be considered. In addition to the variables used in the previous analysis, the following variables were included: dietary nutrient content, crude protein and total digestible nutrient intake, hot carcass weight and yield, fat coverage, and loin eye area. Using all of these data, structures of 3 to 14 groups were formed which were analyzed using Kohonen self-organizing maps. Specimens of the Nellore breed, either intact or castrated, were diluted among groups in hierarchical and non-hierarchical analysis, as well as in the analysis of artificial neural networks. Nellore animals therefore cannot be characterized as having a single behavior when finished in feedlots, since they participate in groups formed with animals of other Zebu breeds (Gyr, Guzerá and with animals of European breeds (Hereford, Aberdeen Angus, Caracu that exhibit different performance potentials.

  8. Finding Risk Groups by Optimizing Artificial Neural Networks on the Area under the Survival Curve Using Genetic Algorithms.

    Directory of Open Access Journals (Sweden)

    Jonas Kalderstam

    Full Text Available We investigate a new method to place patients into risk groups in censored survival data. Properties such as median survival time, and end survival rate, are implicitly improved by optimizing the area under the survival curve. Artificial neural networks (ANN are trained to either maximize or minimize this area using a genetic algorithm, and combined into an ensemble to predict one of low, intermediate, or high risk groups. Estimated patient risk can influence treatment choices, and is important for study stratification. A common approach is to sort the patients according to a prognostic index and then group them along the quartile limits. The Cox proportional hazards model (Cox is one example of this approach. Another method of doing risk grouping is recursive partitioning (Rpart, which constructs a decision tree where each branch point maximizes the statistical separation between the groups. ANN, Cox, and Rpart are compared on five publicly available data sets with varying properties. Cross-validation, as well as separate test sets, are used to validate the models. Results on the test sets show comparable performance, except for the smallest data set where Rpart's predicted risk groups turn out to be inverted, an example of crossing survival curves. Cross-validation shows that all three models exhibit crossing of some survival curves on this small data set but that the ANN model manages the best separation of groups in terms of median survival time before such crossings. The conclusion is that optimizing the area under the survival curve is a viable approach to identify risk groups. Training ANNs to optimize this area combines two key strengths from both prognostic indices and Rpart. First, a desired minimum group size can be specified, as for a prognostic index. Second, the ability to utilize non-linear effects among the covariates, which Rpart is also able to do.

  9. Theoretical studies of the C4 molecule

    International Nuclear Information System (INIS)

    Ritchie, J.P.; King, H.F.; Young, W.S.

    1985-01-01

    Optimized geometries and relative energies for three states of the C 4 molecule have been obtained from single-reference configuration interaction (SRCI) calculations. At the SRCI level, a rhombic form is calculated to lie 1.1 kcal below the triplet form; consideration of the Davidson correction reduces this difference to 0.4 kcal, while more complete basis sets are expected to increase the difference only by about 0.2 kcal. Consideration of these effects and difference in zero-point energy leads to a final estimated splitting of 1.2 kcal, favoring the rhombus. To aid the determination of the ground state, preliminary estimates of the lowest optical transitions were obtained from SRCI calculations and vibrational frequencies were obtained from SCF calculations. Comparison of the calculated results with experimentally obtained spectra suggest the possibility that both the linear triplet and the rhombus may have already been observed. 19 refs., 4 figs., 4 tabs

  10. Study of Aided Diagnosis of Hepatic Carcinoma Based on Artificial Neural Network Combined with Tumor Marker Group

    Science.gov (United States)

    Tan, Shanjuan; Feng, Feifei; Wu, Yongjun; Wu, Yiming

    To develop a computer-aided diagnostic scheme by using an artificial neural network (ANN) combined with tumor markers for diagnosis of hepatic carcinoma (HCC) as a clinical assistant method. 140 serum samples (50 malignant, 40 benign and 50 normal) were analyzed for α-fetoprotein (AFP), carbohydrate antigen 125 (CA125), carcinoembryonic antigen (CEA), sialic acid (SA) and calcium (Ca). The five tumor marker values were then used as ANN inputs data. The result of ANN was compared with that of discriminant analysis by receiver operating characteristic (ROC) curve (AUC) analysis. The diagnostic accuracy of ANN and discriminant analysis among all samples of the test group was 95.5% and 79.3%, respectively. Analysis of multiple tumor markers based on ANN may be a better choice than the traditional statistical methods for differentiating HCC from benign or normal.

  11. From proto-Kranz to C4 Kranz: building the bridge to C4 photosynthesis.

    Science.gov (United States)

    Sage, Rowan F; Khoshravesh, Roxana; Sage, Tammy L

    2014-07-01

    In this review, we examine how the specialized "Kranz" anatomy of C4 photosynthesis evolved from C3 ancestors. Kranz anatomy refers to the wreath-like structural traits that compartmentalize the biochemistry of C4 photosynthesis and enables the concentration of CO2 around Rubisco. A simplified version of Kranz anatomy is also present in the species that utilize C2 photosynthesis, where a photorespiratory glycine shuttle concentrates CO2 into an inner bundle-sheath-like compartment surrounding the vascular tissue. C2 Kranz is considered to be an intermediate stage in the evolutionary development of C4 Kranz, based on the intermediate branching position of C2 species in 14 evolutionary lineages of C4 photosynthesis. In the best-supported model of C4 evolution, Kranz anatomy in C2 species evolved from C3 ancestors with enlarged bundle sheath cells and high vein density. Four independent lineages have been identified where C3 sister species of C2 plants exhibit an increase in organelle numbers in the bundle sheath and enlarged bundle sheath cells. Notably, in all of these species, there is a pronounced shift of mitochondria to the inner bundle sheath wall, forming an incipient version of the C2 type of Kranz anatomy. This incipient version of C2 Kranz anatomy is termed proto-Kranz, and is proposed to scavenge photorespiratory CO2. By doing so, it may provide fitness benefits in hot environments, and thus represent a critical first stage of the evolution of both the C2 and C4 forms of Kranz anatomy. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  12. [Artificial nutrition in the home. Annual information 1996.Group NADYA-SENPE].

    Science.gov (United States)

    Gómez Candela, C; de Cos, A I; Iglesias, C; Carbonell, M D; Camarero, E; Carrera, J A; Celador, A; Chamorro, J; Ferrón, F; García Luna, P P; Goenaga, A; Gómez Enterría, P; León, M; Martí Bomarti, E; Martín Peña, G; Mejías, S; Molina, J B; Moreno, F; Ordóñez, J; Pavón, P; Pedrón, C; Pereira, J L; Pérez de la Cruz, A; Planas, M; Wanden-Berghe, C

    1999-01-01

    Using a simplified questionnaire from the NADYA group, data referring to age, sex, diagnosis, access route, duration, form of administration, complications, and quality of life have been gathered from 1,400 patients (57% male, 43% female) who receive home enteral nutrition, and from 38 patients (20% male and 18% female) who receive home parenteral nutrition. All of these patients come from the 1996 national registry. The most common indication for home enteral nutrition are neoplasias (39%) followed by neurological alterations (33%). The most common access route is oral (48%), followed by a nasogastric tube in 34%, PEG in 10% and surgical ostomies in 7%. The average treatment duration is 6 months. There is an index of 0.74 complications/patient-year (gastrointestinal 0.28 and mechanical alterations 0.19). At the end of the year 58% of the patients continued to use at home enteral nutrition, with a death rate of 17%. The majority of the treated patients presented a severe social disability (28%) or was bed-ridden (22%). The most common indications for home parenteral nutrition are: neoplasia (42%), Crohn_s disease (10%), and mesenteric ischemia (10%). AIDS (8%), radical enteritis (5%), and motility disorders (5%) are less common. In 42% of the cases tunneled catheters are used, and port-a-cath are used in 53%. The average treatment duration is 6.9 months. 1.06 hospitalizations/patient-year have been registered in relation to the nutritional treatment (mainly catheter sepsis). A mortality of 29% is registered, and there is recovery of the oral route in 7.9% of the cases. 50% of the patients present a severe social disability.

  13. De novo Transcriptome Assembly and Comparison of C3, C3-C4, and C4 Species of Tribe Salsoleae (Chenopodiaceae

    Directory of Open Access Journals (Sweden)

    Maximilian Lauterbach

    2017-11-01

    Full Text Available C4 photosynthesis is a carbon-concentrating mechanism that evolved independently more than 60 times in a wide range of angiosperm lineages. Among other alterations, the evolution of C4 from ancestral C3 photosynthesis requires changes in the expression of a vast number of genes. Differential gene expression analyses between closely related C3 and C4 species have significantly increased our understanding of C4 functioning and evolution. In Chenopodiaceae, a family that is rich in C4 origins and photosynthetic types, the anatomy, physiology and phylogeny of C4, C2, and C3 species of Salsoleae has been studied in great detail, which facilitated the choice of six samples of five representative species with different photosynthetic types for transcriptome comparisons. mRNA from assimilating organs of each species was sequenced in triplicates, and sequence reads were de novo assembled. These novel genetic resources were then analyzed to provide a better understanding of differential gene expression between C3, C2 and C4 species. All three analyzed C4 species belong to the NADP-ME type as most genes encoding core enzymes of this C4 cycle are highly expressed. The abundance of photorespiratory transcripts is decreased compared to the C3 and C2 species. Like in other C4 lineages of Caryophyllales, our results suggest that PEPC1 is the C4-specific isoform in Salsoleae. Two recently identified transporters from the PHT4 protein family may not only be related to the C4 syndrome, but also active in C2 photosynthesis in Salsoleae. In the two populations of the C2 species S. divaricata transcript abundance of several C4 genes are slightly increased, however, a C4 cycle is not detectable in the carbon isotope values. Most of the core enzymes of photorespiration are highly increased in the C2 species compared to both C3 and C4 species, confirming a successful establishment of the C2 photosynthetic pathway. Furthermore, a function of PEP-CK in C2 photosynthesis

  14. Olefins production from C4 stream; Producao de olefinas a partir de corrente C4

    Energy Technology Data Exchange (ETDEWEB)

    Basso, Julia A.; Feltran, Marina B.; Becker, Patricia Luiza; Rocha, Priscila L. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The petrochemical sector in Brazil has been growing in terms of investment and expansion of production capacity, due to increased demand for thermoplastic products. However, the offer of basic petrochemical raw materials obtained by conventional routes is not following this increasing demand which stimulates the search for new competitive technologies. Moreover, there is the opportunity to use low value added C4 streams from FCC process that are available in the Brazilian refineries, for the production of petrochemicals. Several possibilities of C4 stream use to produce butadienes, MTBE, maleic anhydride, ethylene and propylene have been discussed in this work. The production of propylene seems to be the most economically attractive option in Brazil, since its offer will not keep up with the growth in its demand, according to ABIQUIM forecasts. Therefore some propylene production technologies from C4 streams - steam cracking, metathesis and selective cracking - have been evaluated considering their basic characteristics and applications. The goal of this study is to provide preliminary information to support future project evaluations of petrochemical/refinery integration, through comparative analysis of these technologies. (author)

  15. The C4ISR Architecture Framework: History, Status, and Plans for Evolution

    Science.gov (United States)

    2000-08-01

    into their document, which is entitled The Open Group Architecture Framework ( TOGAF ) [Author’s Correspondence, 2000]. The C4ISR Architecture...1998, Subject: Strategic Direction for a Dod Architecture Framework. [Author’s Correspondence, 2000] Communication with TOGAF committee members. [C4ISR

  16. C4 polymorphism and extended HLA haplotypes in Namibian San and Khoi and in South African Xhosa.

    Science.gov (United States)

    Creemers, P C; du Toit, E D

    1996-02-01

    We studied C4A and C4B polymorphisms and HLA-B and -DR associations in the San, Khoi and Xhosa. C4A and C4B alleles were determined using conventional protein allotyping methods. The C4A*3, C4B*1 haplotype had a high frequency (30-55%) in all populations. The frequency of C4A*3, C4B*Q0 was 7-19%. The C4A*Q0, C4B*1 haplotype was frequent (15%) in the Khoi but very rare in the San (P Xhosa (15%) but rare in the San and Khoi (P Xhosa. C4A alleles A*4, A*45, A*58, A*12, A*14, A*19 and the C4A*3 A*91 duplication were only found in the San/Khoi population group. In the San, fourteen extended haplotypes were found in a relatively high frequency (2-7%). In the Xhosa, one extended haplotype (B42, C4A*12 A*91, C4B*Q0, DR18) was found in a very high frequency (13%) and was characteristic for this group; five other extended haplotypes were found with a low frequency (< 3%).

  17. Product Manager C4ISR On-The-Move Experimentation

    National Research Council Canada - National Science Library

    Utroska, William; Langan, Russell; Amabile, Michael

    2006-01-01

    Product Manager C4ISR On-The-Move (PM C4ISR OTM) provides a relevant operational field experimentation venue for the purpose of assessing emerging technologies in a System-of- Systems (SoS) environment...

  18. Complement C4 phenotypes in dementia of the Alzheimer type

    NARCIS (Netherlands)

    Eikelenboom, P.; Goetz, J.; Pronk, J. C.; Hauptmann, G.

    1988-01-01

    Complement C4 phenotype distribution was studied in 64 patients with dementia of the Alzheimer type. In contrast to reported findings we failed to find a significant association between C4B2 gene frequency and Alzheimer's dementia

  19. Shared origins of a key enzyme during the evolution of C4 and CAM metabolism

    Science.gov (United States)

    Christin, Pascal-Antoine; Arakaki, Monica; Osborne, Colin P.; Bräutigam, Andrea; Sage, Rowan F.; Hibberd, Julian M.; Kelly, Steven; Covshoff, Sarah; Wong, Gane Ka-Shu; Hancock, Lillian; Edwards, Erika J.

    2014-01-01

    CAM and C4 photosynthesis are two key plant adaptations that have evolved independently multiple times, and are especially prevalent in particular groups of plants, including the Caryophyllales. We investigate the origin of photosynthetic PEPC, a key enzyme of both the CAM and C4 pathways. We combine phylogenetic analyses of genes encoding PEPC with analyses of RNA sequence data of Portulaca, the only plants known to perform both CAM and C4 photosynthesis. Three distinct gene lineages encoding PEPC exist in eudicots (namely ppc-1E1, ppc-1E2 and ppc-2), one of which (ppc-1E1) was recurrently recruited for use in both CAM and C4 photosynthesis within the Caryophyllales. This gene is present in multiple copies in the cacti and relatives, including Portulaca. The PEPC involved in the CAM and C4 cycles of Portulaca are encoded by closely related yet distinct genes. The CAM-specific gene is similar to genes from related CAM taxa, suggesting that CAM has evolved before C4 in these species. The similar origin of PEPC and other genes involved in the CAM and C4 cycles highlights the shared early steps of evolutionary trajectories towards CAM and C4, which probably diverged irreversibly only during the optimization of CAM and C4 phenotypes. PMID:24638902

  20. Plastidial NADP-malic enzymes from grasses: unraveling the way to the C4 specific isoforms.

    Science.gov (United States)

    Saigo, Mariana; Alvarez, Clarisa E; Andreo, Carlos S; Drincovich, María F

    2013-02-01

    Malic enzyme is present in many plant cell compartments such as plastids, cytosol and mitochondria. Particularly relevant is the plastidial isoform that participates in the C(4) cycle providing CO(2) to RuBisCO in C(4) species. This type of photosynthesis is more frequent among grasses where anatomical preconditioning would have facilitated the evolution of the C(4) syndrome. In maize (C(4) grass), the photosynthetic NADP dependent Malic enzyme (ZmC(4)-NADP-ME, l-malate:NADP oxidoreductase, E.C. 1.1.1.40) and the closest related non-photosynthetic isoform (ZmnonC(4)-NADP-ME, l-malate:NADP oxidoreductase, E.C. 1.1.1.40) are both plastidial but differ in expression pattern, kinetics and structure. Features like high catalytic efficiency, inhibition by high malate concentration at pH 7.0, redox modulation and tetramerization are characteristic of the photosynthetic NADP-ME. In this work, the proteins encoded by sorghum (C(4) grass) and rice (C(3) grass) NADP-ME genes, orthologues of the plastidial NADP-MEs from maize, were recombinantly expressed, purified and characterized. In a global comparison, we could identify a small group of residues which may explain the special features of C(4) enzymes. Overall, the present work presents biochemical and molecular data that helps to elucidate the changes that took place in the evolution of C(4) NADP-ME in grasses. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  1. C4 Nephritic Factors in C3 Glomerulopathy: A Case Series.

    Science.gov (United States)

    Zhang, Yuzhou; Meyer, Nicole C; Fervenza, Fernando C; Lau, Winnie; Keenan, Adam; Cara-Fuentes, Gabriel; Shao, Dingwu; Akber, Aalia; Fremeaux-Bacchi, Veronique; Sethi, Sanjeev; Nester, Carla M; Smith, Richard J H

    2017-12-01

    C3 glomerulopathy (C3G) defines a group of rare complement-mediated kidney diseases with a shared underlying pathophysiology: dysregulation of complement in the fluid phase and glomerular microenvironment. Dysregulation can be driven by autoantibodies to C3 and C5 convertases. Case series. 168 patients with C3G (dense deposit disease, 68; C3 glumerulonephritis, 100) selected from our C3G biobank. Patient-purified immunoglobulin Gs were tested for C4 nephritic factors (C4NeFs). These autoantibodies recognize C4b2a, the C3 convertase of the classical pathway of complement. C4NeFs were detected using a modified hemolytic assay. C4NeFs were identified in 5 patients, 4 of whom had C3 glomerulonephritis. C4NeFs were associated with dysregulation of C3 and C5 convertases, and they appear to stabilize these convertases in a dose-dependent manner. C4NeFs also appear to protect C4b2a from decay mediated by soluble CR1 and C4 binding protein. The stabilizing activity of the autoantibodies was further demonstrated by using heat treatment to inactivate complement. C4NeFs were not detected in 150 patients with another complement-mediated kidney disease, atypical hemolytic uremic syndrome. They were also absent in 300 apparently healthy controls. In addition to C4NeFs, 2 patients had positive findings for other autoantibodies: one patient also had autoantibodies to factor H; the other patient also had autoantibodies to C3bBb (C3NeFs). The finding of C4NeFs in a small percentage of patients with C3G highlights the challenge in identifying autoantibodies that drive complement dysregulation and underscores the complexity of the autoantibody repertoire that can be identified in these patients. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Characterization of a C 4 maize pyruvate orthophosphate dikinase ...

    African Journals Online (AJOL)

    Pyruvate orthophosphate dikinase (PPDK) is a key enzyme in plants that utilize the C4 photosynthetic pathway to fix CO2. The enzymatic reaction catalyzed by PPDK is critically controlled by light and is one of the rate-limiting steps of the C4 pathway. The intact maize (Zea mays) C4-PPDK gene, containing its own promoter, ...

  3. 19 CFR 142.49 - Deletion of C-4 Code.

    Science.gov (United States)

    2010-04-01

    .... Entry filers may delete C-4 Codes from Line Release by notifying the port director in writing on a Deletion Data Loading Sheet. Such notification shall state the C-4 Code which is to be deleted, the port... TREASURY (CONTINUED) ENTRY PROCESS Line Release § 142.49 Deletion of C-4 Code. (a) By Customs. A port...

  4. 26 CFR 1.1092(c)-4 - Definitions.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Definitions. 1.1092(c)-4 Section 1.1092(c)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Wash Sales of Stock Or Securities § 1.1092(c)-4 Definitions. The following definitions apply...

  5. 17 CFR 240.16c-4 - Derivative securities.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Derivative securities. 240.16c-4 Section 240.16c-4 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED... Exchange Act of 1934 Exemption of Certain Transactions from Section 16(c) § 240.16c-4 Derivative securities...

  6. Complement factor C4 activation in patients with hereditary angioedema

    DEFF Research Database (Denmark)

    Åbom, Anne; Bygum, Anette; Koch, Claus

    2017-01-01

    , that C1-INH-HAE may potentially be overlooked, if screening is performed only by measurement of C4. It has been suggested that measurement of C4 activation products is better suited to avoid false negative results. Our aim was to investigate whether total antigenic C4 or non-functional C4c is a better......Objectives: Low complement factor C4 is usually considered a valuable screening tool for patients with the potentially life-threatening hereditary angioedema with C1-inhibitor (C1-INH) deficiency (C1-INH-HAE). However, there are patients with C1-INH-HAE presenting with normal C4 levels. This means...... measure of the increased C4 activation in C1-INH-HAE patients. Design and methods: Two different monoclonal antibodies (mAb) to human C4 were produced: one had specificity for the β-chain of C4 and would thus react with both functional and non-functional C4, and the other was developed against the factor...

  7. Photosynthesis in C3-C4 intermediate Moricandia species.

    Science.gov (United States)

    Schlüter, Urte; Bräutigam, Andrea; Gowik, Udo; Melzer, Michael; Christin, Pascal-Antoine; Kurz, Samantha; Mettler-Altmann, Tabea; Weber, Andreas Pm

    2017-01-01

    Evolution of C 4 photosynthesis is not distributed evenly in the plant kingdom. Particularly interesting is the situation in the Brassicaceae, because the family contains no C 4 species, but several C 3 -C 4 intermediates, mainly in the genus Moricandia Investigation of leaf anatomy, gas exchange parameters, the metabolome, and the transcriptome of two C 3 -C 4 intermediate Moricandia species, M. arvensis and M. suffruticosa, and their close C 3 relative M. moricandioides enabled us to unravel the specific C 3 -C 4 characteristics in these Moricandia lines. Reduced CO 2 compensation points in these lines were accompanied by anatomical adjustments, such as centripetal concentration of organelles in the bundle sheath, and metabolic adjustments, such as the balancing of C and N metabolism between mesophyll and bundle sheath cells by multiple pathways. Evolution from C 3 to C 3 -C 4 intermediacy was probably facilitated first by loss of one copy of the glycine decarboxylase P-protein, followed by dominant activity of a bundle sheath-specific element in its promoter. In contrast to recent models, installation of the C 3 -C 4 pathway was not accompanied by enhanced activity of the C 4 cycle. Our results indicate that metabolic limitations connected to N metabolism or anatomical limitations connected to vein density could have constrained evolution of C 4 in Moricandia. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  8. Development and Analysis of Integrated C4ISR Architectures

    National Research Council Canada - National Science Library

    Giammarco, Kristin; Carlomusto, Michael; Lock, J. D

    2005-01-01

    .... This paper presents an overview of the Communications- Electronics Research, Development, and Engineering Center Command, Control, Communications, Computer, Intelligence, Surveillance, and Reconnaissance (C4ISR...

  9. Integrated environment for architecture design of C4ISR system

    Science.gov (United States)

    Luo, Aimin; Luo, Xueshan; Zhang, Yaohong; Xiu, Shenglong

    2004-09-01

    Architecture design of C4ISR system is the foundation for system integration. Based on C4ISR architecture framework, this paper analyzed the characters of architecture products, classified the design tools of architecture into different kinds and defined functions of design tools, proposed the architecture design integrate framework, and then realized architecture design tools and integrated environment.

  10. The roles of organic acids in C4 photosynthesis

    Directory of Open Access Journals (Sweden)

    Martha eLudwig

    2016-05-01

    Full Text Available Organic acids are involved in numerous metabolic pathways in all plants. The finding that some plants, known as C4 plants, have four-carbon dicarboxylic acids as the first product of carbon fixation showed these organic acids play essential roles as photosynthetic intermediates. Oxaloacetate, malate, and aspartate are substrates for the C4 acid cycle that underpins the CO2 concentrating mechanism of C4 photosynthesis. In this cycle, oxaloacetate is the immediate, short-lived, product of the initial CO2 fixation step in C4 leaf mesophyll cells. The malate and aspartate, resulting from the rapid conversion of oxaloacetate, are the organic acids delivered to the sites of carbon reduction in the bundle-sheath cells of the leaf, where they are decarboxylated, with the released CO2 used to make carbohydrates. The three-carbon organic acids resulting from the decarboxylation reactions are returned to the mesophyll cells where they are used to regenerate the CO2 acceptor pool. NADP-malic enzyme-type, NAD-malic enzyme-type and phosphoenolpyruvate carboxykinase-type C4 plants were identified, based on the most abundant decarboxylating enzyme in the leaf tissue. The genes encoding these C4 pathway-associated decarboxylases were co-opted from ancestral C3 plant genes during the evolution of C4 photosynthesis. Malate was recognized as the major organic acid transferred in NADP-malic enzyme-type C4 species, while aspartate fills this role in NAD-malic enzyme-type and phosphoenolpyruvate carboxykinase-type plants. However, accumulating evidence indicates that many C4 plants use a combination of organic acids and decarboxylases during CO2 fixation, and the C4-type categories are not rigid. The ability to transfer multiple organic acid species and utilize different decarboxylases has been suggested to give C4 plants advantages in changing and stressful environments, as well as during development, by facilitating the balance of energy between the two cell types

  11. Carbon isotope discrimination as a diagnostic tool for C4 photosynthesis in C3-C4 intermediate species

    Science.gov (United States)

    Alonso-Cantabrana, Hugo; von Caemmerer, Susanne

    2016-01-01

    The presence and activity of the C4 cycle in C3-C4 intermediate species have proven difficult to analyze, especially when such activity is low. This study proposes a strategy to detect C4 activity and estimate its contribution to overall photosynthesis in intermediate plants, by using tunable diode laser absorption spectroscopy (TDLAS) coupled to gas exchange systems to simultaneously measure the CO2 responses of CO2 assimilation (A) and carbon isotope discrimination (Δ) under low O2 partial pressure. Mathematical models of C3-C4 photosynthesis and Δ are then fitted concurrently to both responses using the same set of constants. This strategy was applied to the intermediate species Flaveria floridana and F. brownii, and to F. pringlei and F. bidentis as C3 and C4 controls, respectively. Our results support the presence of a functional C4 cycle in F. floridana, that can fix 12–21% of carbon. In F. brownii, 75–100% of carbon is fixed via the C4 cycle, and the contribution of mesophyll Rubisco to overall carbon assimilation increases with CO2 partial pressure in both intermediate plants. Combined gas exchange and Δ measurement and modeling is a powerful diagnostic tool for C4 photosynthesis. PMID:26862154

  12. The recurrent assembly of C4 photosynthesis, an evolutionary tale.

    Science.gov (United States)

    Christin, Pascal-Antoine; Osborne, Colin P

    2013-11-01

    Today, plants using C4 photosynthesis are widespread and important components of major tropical and subtropical biomes, but the events that led to their evolution and success started billions of years ago (bya). A CO2-fixing enzyme evolved in the early Earth atmosphere with a tendency to confuse CO2 and O2 molecules. The descendants of early photosynthetic organisms coped with this property in the geological eras that followed through successive fixes, the latest of which is the addition of complex CO2-concentrating mechanisms such as C4 photosynthesis. This trait was assembled from bricks available in C3 ancestors, which were altered to fulfill their new role in C4 photosynthesis. The existence of C4-suitable bricks probably determined the lineages of plants that could make the transition to C4 photosynthesis, highlighting the power of contingency in evolution. Based on the latest findings in C4 research, we present the evolutionary tale of C4 photosynthesis, with a focus on the general evolutionary phenomena that it so wonderfully exemplifies.

  13. A study of immunoglobulins and complements (C3 &C4 in alopecia areata

    Directory of Open Access Journals (Sweden)

    Sharma R

    1995-01-01

    Full Text Available Estimation of serum Immunoglobulins (IgG, IgM and IgA and complements (C3 and C4 was carried out in 100 cases of alopecia areata as per method described by Mancini (1965.[1] Clinically patients were divided in two groups, alopecia areata circumscribed (group I and severe alopecia areata (group II. Significant decrease in levels of one or more Immunoglobulins were observed in most of the patients. However, Serum complements (C3 and C4 were within range of normal control values

  14. Isomerisation of c4-c6 aldoses with zeolites

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to isomerization of C4-C6 aldoses to their corresponding C4-C6 ketoses. In particular, the invention concerns isomerization of C4-C6 aldoses over solid zeolite catalysts free of any metals other than aluminum, in the presence of suitable solvent(s) at suitable elevat...... in the catalyst. The ketoses obtained are used as sweeteners in the food and/or brewery industry, or treated to obtain downstream platform chemicals such as lactic acid, HMF, levulinic acid, furfural, MMHB, and the like....

  15. C4.5 programs for machine learning

    CERN Document Server

    Quinlan, J Ross

    1992-01-01

    Classifier systems play a major role in machine learning and knowledge-based systems, and Ross Quinlan's work on ID3 and C4.5 is widely acknowledged to have made some of the most significant contributions to their development. This book is a complete guide to the C4.5 system as implemented in C for the UNIX environment. It contains a comprehensive guide to the system's use , the source code (about 8,800 lines), and implementation notes. The source code and sample datasets are also available for download (see below). C4.5 starts with large sets of cases belonging to known classes. The cases,

  16. C4ISR system for warfighter and its integration technologies

    Science.gov (United States)

    Wu, Hongyun

    2000-08-01

    The paper describes overall functions, system configuration and its overall technologies concerned of C4ISR system or information network system for warfighter with the emphasis on the use of COTS information network system concepts, principles, designing thinking, architecture and network technologies for implementing the desired C4ISR structure. Two subjects are included: research on the composition of warfighter C4ISR system from the aspects of overall functional features and structure features; research on the overall technologies of digital warfighter system with emphasis on the discussion of integrated structure system, information collection and processing methods, and the technologies and scheme of information network system.

  17. C4 photosynthetic machinery: insights from maize chloroplast proteomics

    Directory of Open Access Journals (Sweden)

    Qi eZhao

    2013-04-01

    Full Text Available C4 plants exhibit much higher CO2 assimilation rates than C3 plants. The specialized differentiation of mesophyll cell (M and bundle sheath cell (BS type chloroplasts is unique to C4 plants and improves photosynthesis efficiency. Maize (Zea mays is an important crop and model with C4 photosynthetic machinery. Current high-throughput quantitative proteomics approaches (e.g., 2DE, iTRAQ, and shotgun proteomics have been employed to investigate maize chloroplast structure and function. These proteomic studies have provided valuable information on C4 chloroplast protein components, photosynthesis, and other metabolic mechanisms underlying chloroplast biogenesis, stromal and membrane differentiation, as well as response to salinity, high/low temperature, and light stress. This review presents an overview of proteomics advances in maize chloroplast biology.

  18. Aerial energetic residue data from JBER C4 testing

    Data.gov (United States)

    U.S. Environmental Protection Agency — Aerially-collected energetic residues from surface detonation of C4. This dataset is associated with the following publication: Walsh, M., B. Gullett, M. Walsh, M....

  19. Joint C4ISR Architecture Planning/Analysis System (JCAPS)

    National Research Council Canada - National Science Library

    Wostbrock, Bill

    2002-01-01

    The contractor satisfactorily completed all tasks under both efforts, providing the technology and technical expertise in the development of the Joint C4ISR Architecture Planning/Analysis System (JCAPS) Database Tool...

  20. C4P cross-section libraries for safety analyses with SIMMER and related studies

    International Nuclear Information System (INIS)

    Rineiski, A.; Sinitsa, V.; Gabrielli, F.; Maschek, W.

    2011-01-01

    A code and data system, C 4 P, is under development at KIT. It includes fine-group master libraries and tools for generating problem-oriented cross-section libraries, primarily for safety studies with the SIMMER code and related analyses. In the paper, the 560-group master library and problem oriented 40-group and 72-group cross-section libraries, for thermal and fast systems, respectively, are described and their performances are investigated. (author)

  1. The dicotyledonous NAD malic enzyme C4 plant Cleome gynandra displays age-dependent plasticity of C4 decarboxylation biochemistry.

    Science.gov (United States)

    Sommer, M; Bräutigam, A; Weber, A P M

    2012-07-01

    The C(4) photosynthetic pathway enriches carbon dioxide in the vicinity of Rubisco, thereby enabling plants to assimilate carbon more efficiently. Three canonical subtypes of C(4) exist, named after their main decarboxylating enzymes: NAD-dependent malic enzyme type, NADP-dependent malic enzyme type and phosphoenolpyruvate carboxykinase type. Cleome gynandra is known to perform NAD-ME type C(4) photosynthesis. To further assess the mode of C(4) in C. gynandra and its manifestation in leaves of different age, total enzyme activities of eight C(4) -related enzymes and the relative abundance of 31 metabolites were measured. C. spinosa was used as a C(3) control. C. gynandra was confirmed as an NAD-ME type C(4) plant in mid-aged leaves, whereas a mixed NAD-ME and PEPCK type was observed in older leaves. Young leaves showed a C(3) -C(4) intermediate state with respect to enzyme activities and metabolite abundances. Comparative transcriptome analysis of mid-aged leaves of C. gynandra and C. spinosa showed that the transcript of only one aspartate aminotransferase (AspAT) isoform is highly abundant in C. gynandra. However, the canonical model of the NAD-ME pathway requires two AspATs, a mitochondrial and a cytosolic isoform. Surprisingly, our results indicate the existence of only one highly abundant AspAT isoform. Using GFP-fusion, this isozyme was localised exclusively to mitochondria. We propose a revised model of NAD-ME type C(4) photosynthesis in C. gynandra, in which both AspAT catalysed reactions take place in mitochondria and PEPCK catalyses an alternative decarboxylating pathway. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  2. Technologies for network-centric C4ISR

    Science.gov (United States)

    Dunkelberger, Kirk A.

    2003-07-01

    Three technologies form the heart of any network-centric command, control, communication, intelligence, surveillance, and reconnaissance (C4ISR) system: distributed processing, reconfigurable networking, and distributed resource management. Distributed processing, enabled by automated federation, mobile code, intelligent process allocation, dynamic multiprocessing groups, check pointing, and other capabilities creates a virtual peer-to-peer computing network across the force. Reconfigurable networking, consisting of content-based information exchange, dynamic ad-hoc routing, information operations (perception management) and other component technologies forms the interconnect fabric for fault tolerant inter processor and node communication. Distributed resource management, which provides the means for distributed cooperative sensor management, foe sensor utilization, opportunistic collection, symbiotic inductive/deductive reasoning and other applications provides the canonical algorithms for network-centric enterprises and warfare. This paper introduces these three core technologies and briefly discusses a sampling of their component technologies and their individual contributions to network-centric enterprises and warfare. Based on the implied requirements, two new algorithms are defined and characterized which provide critical building blocks for network centricity: distributed asynchronous auctioning and predictive dynamic source routing. The first provides a reliable, efficient, effective approach for near-optimal assignment problems; the algorithm has been demonstrated to be a viable implementation for ad-hoc command and control, object/sensor pairing, and weapon/target assignment. The second is founded on traditional dynamic source routing (from mobile ad-hoc networking), but leverages the results of ad-hoc command and control (from the contributed auctioning algorithm) into significant increases in connection reliability through forward prediction. Emphasis

  3. Mitochondrial haplogroup C4c: a rare lineage entering America through the ice-free corridor?

    Science.gov (United States)

    Hooshiar Kashani, Baharak; Perego, Ugo A; Olivieri, Anna; Angerhofer, Norman; Gandini, Francesca; Carossa, Valeria; Lancioni, Hovirag; Semino, Ornella; Woodward, Scott R; Achilli, Alessandro; Torroni, Antonio

    2012-01-01

    Recent analyses of mitochondrial genomes from Native Americans have brought the overall number of recognized maternal founding lineages from just four to a current count of 15. However, because of their relative low frequency, almost nothing is known for some of these lineages. This leaves a considerable void in understanding the events that led to the colonization of the Americas following the Last Glacial Maximum (LGM). In this study, we identified and completely sequenced 14 mitochondrial DNAs belonging to one extremely rare Native American lineage known as haplogroup C4c. Its age and geographical distribution raise the possibility that C4c marked the Paleo-Indian group(s) that entered North America from Beringia through the ice-free corridor between the Laurentide and Cordilleran ice sheets. The similarities in ages andgeographical distributions for C4c and the previously analyzed X2a lineage provide support to the scenario of a dual origin for Paleo-Indians. Taking into account that C4c is deeply rooted in the Asian portion of the mtDNA phylogeny and is indubitably of Asian origin, the finding that C4c and X2a are characterized by parallel genetic histories definitively dismisses the controversial hypothesis of an Atlantic glacial entry route into North America. Copyright © 2011 Wiley Periodicals, Inc.

  4. Modeling and computations of the intramolecular electron transfer process in the two-heme protein cytochrome c4

    DEFF Research Database (Denmark)

    Natzmutdinov, Renat R.; Bronshtein, Michael D.; Zinkicheva, Tamara T.

    2012-01-01

    The di-heme protein Pseudomonas stutzeri cytochrome c4 (cyt c4) has emerged as a useful model for studying long-range protein electron transfer (ET). Recent experimental observations have shown a dramatically different pattern of intramolecular ET between the two heme groups in different local...

  5. Artificial intelligence

    CERN Document Server

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  6. Performance and behaviour of rabbit does in a group-housing system with natural mating or artificial insemination

    NARCIS (Netherlands)

    Rommers, J.M.; Boiti, C.; Jong, de I.C.; Brecchia, G.

    2006-01-01

    This study compared reproductive performance and behaviour of does raised in a group-housing system and in a regular cage system. The group-housing pen was divided into different functional areas for suckling, resting, and eating and special hiding areas for kits when they had left the nest-boxes

  7. 118-C-4 Horizontal Rod Cave Characterization Report

    International Nuclear Information System (INIS)

    Encke, B.D.; Thoren, R.A.

    1998-03-01

    This report addresses the characterization data collected from 118-C- 4 Horizontal Rod Cave in December 1996 and August 1997. The characterization activities evaluated the radiological status and identified hazardous materials locations. The scope of this report is limited to the 118-C-4 Facility Structure. Information in this report can be used to identify the waste streams, provide specific chemical and radiological data to aid in planning decontamination and decommissioning (D ampersand D) activities, and allow proper disposal of the demolition debris, as required by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980

  8. Hybrid Pareto artificial bee colony algorithm for multi-objective single machine group scheduling problem with sequence-dependent setup times and learning effects.

    Science.gov (United States)

    Yue, Lei; Guan, Zailin; Saif, Ullah; Zhang, Fei; Wang, Hao

    2016-01-01

    Group scheduling is significant for efficient and cost effective production system. However, there exist setup times between the groups, which require to decrease it by sequencing groups in an efficient way. Current research is focused on a sequence dependent group scheduling problem with an aim to minimize the makespan in addition to minimize the total weighted tardiness simultaneously. In most of the production scheduling problems, the processing time of jobs is assumed as fixed. However, the actual processing time of jobs may be reduced due to "learning effect". The integration of sequence dependent group scheduling problem with learning effects has been rarely considered in literature. Therefore, current research considers a single machine group scheduling problem with sequence dependent setup times and learning effects simultaneously. A novel hybrid Pareto artificial bee colony algorithm (HPABC) with some steps of genetic algorithm is proposed for current problem to get Pareto solutions. Furthermore, five different sizes of test problems (small, small medium, medium, large medium, large) are tested using proposed HPABC. Taguchi method is used to tune the effective parameters of the proposed HPABC for each problem category. The performance of HPABC is compared with three famous multi objective optimization algorithms, improved strength Pareto evolutionary algorithm (SPEA2), non-dominated sorting genetic algorithm II (NSGAII) and particle swarm optimization algorithm (PSO). Results indicate that HPABC outperforms SPEA2, NSGAII and PSO and gives better Pareto optimal solutions in terms of diversity and quality for almost all the instances of the different sizes of problems.

  9. Improving our understanding of environmental controls on the distribution of C3 and C4 grasses.

    Science.gov (United States)

    Pau, Stephanie; Edwards, Erika J; Still, Christopher J

    2013-01-01

    A number of studies have demonstrated the ecological sorting of C3 and C4 grasses along temperature and moisture gradients. However, previous studies of C3 and C4 grass biogeography have often inadvertently compared species in different and relatively unrelated lineages, which are associated with different environmental settings and distinct adaptive traits. Such confounded comparisons of C3 and C4 grasses may bias our understanding of ecological sorting imposed strictly by photosynthetic pathway. Here, we used MaxEnt species distribution modeling in combination with satellite data to understand the functional diversity of C3 and C4 grasses by comparing both large clades and closely related sister taxa. Similar to previous work, we found that C4 grasses showed a preference for regions with higher temperatures and lower precipitation compared with grasses using the C3 pathway. However, air temperature differences were smaller (2 °C vs. 4 °C) and precipitation and % tree cover differences were larger (1783 mm vs. 755 mm, 21.3% vs. 7.7%, respectively) when comparing C3 and C4 grasses within the same clade vs. comparing all C4 and all C3 grasses (i.e., ignoring phylogenetic structure). These results were due to important differences in the environmental preferences of C3 BEP and PACMAD clades (the two main grass clades). Winter precipitation was found to be more important for understanding the distribution and environmental niche of C3 PACMADs in comparison with both C3 BEPs and C4 taxa, for which temperature was much more important. Results comparing closely related C3 -C4 sister taxa supported the patterns derived from our modeling of the larger clade groupings. Our findings, which are novel in comparing the distribution and niches of clades, demonstrate that the evolutionary history of taxa is important for understanding the functional diversity of C3 and C4 grasses, and should have implications for how grasslands will respond to global change. © 2012

  10. Evolution of CAM and C4 carbon-concentrating mechanisms

    Science.gov (United States)

    Keeley, Jon E.; Rundel, Philip W.

    2003-01-01

    Mechanisms for concentrating carbon around the Rubisco enzyme, which drives the carbon-reducing steps in photosynthesis, are widespread in plants; in vascular plants they are known as crassulacean acid metabolism (CAM) and C4 photosynthesis. CAM is common in desert succulents, tropical epiphytes, and aquatic plants and is characterized by nighttime fixation of CO2. The proximal selective factor driving the evolution of this CO2-concentrating pathway is low daytime CO2, which results from the unusual reverse stomatal behavior of terrestrial CAM species or from patterns of ambient CO2 availability for aquatic CAM species. In terrestrials the ultimate selective factor is water stress that has selected for increased water use efficiency. In aquatics the ultimate selective factor is diel fluctuations in CO2 availability for palustrine species and extreme oligotrophic conditions for lacustrine species. C4 photosynthesis is based on similar biochemistry but carboxylation steps are spatially separated in the leaf rather than temporally as in CAM. This biochemical pathway is most commonly associated with a specialized leaf anatomy known as Kranz anatomy; however, there are exceptions. The ultimate selective factor driving the evolution of this pathway is excessively high photorespiration that inhibits normal C3 photosynthesis under high light and high temperature in both terrestrial and aquatic habitats. CAM is an ancient pathway that likely has been present since the Paleozoic era in aquatic species from shallow-water palustrine habitats. While atmospheric CO2 levels have undoubtedly affected the evolution of terrestrial plant carbon-concentrating mechanisms, there is reason to believe that past atmospheric changes have not played as important a selective role in the aquatic milieu since palustrine habitats today are not generally carbon sinks, and the selective factors driving aquatic CAM are autogenic. Terrestrial CAM, in contrast, is of increasing selective value under

  11. The potential of C4 grasses for cellulosic biofuel production

    NARCIS (Netherlands)

    Weijde, van der R.T.; Alvim Kamei, C.L.; Torres Salvador, A.F.; Vermerris, W.; Dolstra, O.; Visser, R.G.F.; Trindade, L.M.

    2013-01-01

    With the advent of biorefinery technologies enabling plant biomass to be processed into biofuel, many researchers set out to study and improve candidate biomass crops. Many of these candidates are C4 grasses, characterized by a high productivity and resource use efficiency. In this review the

  12. Transport biofuel yields from food and lignocellulosic C4 crops

    NARCIS (Netherlands)

    Reijnders, L.

    2010-01-01

    In the near future, the lignocellulosic C4 crops Miscanthus and switchgrass (Panicum virgatum) are unlikely to outcompete sugarcane (Saccharum officinarum) in net energetic yearly yield of transport biofuel ha(-1). This holds both for the thermochemical conversion into liquid hydrocarbons and the

  13. Microscale modeling of gas exchange during C4 photosythesis

    NARCIS (Netherlands)

    Retta, Moges

    2017-01-01

    Improving the efficiency of photosynthesis could contribute to better food security under an unprecedented rise in global population and climate-change. The photosynthesis pathway in C4 plants, such as maize (Zea mays L.), Miscanthus (Miscanthus x giganteus), and sugarcane (Saccharum officinarum

  14. 12 CFR 563c.4 - Condensed financial information [Parent only].

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Condensed financial information [Parent only... ACCOUNTING REQUIREMENTS Form and Content of Financial Statements § 563c.4 Condensed financial information [Parent only]. (a) The information prescribed by Schedule III required by section IV of § 563c.102 of this...

  15. Senescence, dormancy and tillering in perennial C4 grasses

    Science.gov (United States)

    Perennial, temperate, C4 warm-season grasses, such as switchgrass and miscanthus have been tabbed as sources of herbaceous biomass for the production of green fuels and chemicals based on a number of positive agronomic traits. Although there is important literature on the management of these specie...

  16. Microscale modeling of gas exchange during C4 photosythesis

    NARCIS (Netherlands)

    Retta, Moges

    2017-01-01

    Improving the efficiency of photosynthesis could contribute to better food security under an unprecedented rise in global population and climate-change. The photosynthesis pathway in C4 plants, such as maize (Zea mays L.), Miscanthus (Miscanthus x giganteus), and

  17. Pitfalls of artificial grouping and stratification of scientific journals based on their Impact Factor: a case study in Brazilian Zoology

    OpenAIRE

    Machado, Fábio A.; Zaher, Hussam

    2010-01-01

    The present contribution explores the impact of the QUALIS metric system for academic evaluation implemented by CAPES (Coordination for the Development of Personnel in Higher Education) upon Brazilian Zoological research. The QUALIS system is based on the grouping and ranking of scientific journals according to their Impact Factor (IF). We examined two main points implied by this system, namely: 1) its reliability as a guideline for authors; 2) if Zoology possesses the same publication profil...

  18. Pitfalls of artificial grouping and stratification of scientific journals based on their Impact Factor: a case study in Brazilian Zoology

    Directory of Open Access Journals (Sweden)

    Fábio A. Machado

    2010-08-01

    Full Text Available The present contribution explores the impact of the QUALIS metric system for academic evaluation implemented by CAPES (Coordination for the Development of Personnel in Higher Education upon Brazilian Zoological research. The QUALIS system is based on the grouping and ranking of scientific journals according to their Impact Factor (IF. We examined two main points implied by this system, namely: 1 its reliability as a guideline for authors; 2 if Zoology possesses the same publication profile as Botany and Oceanography, three fields of knowledge grouped by CAPES under the subarea "BOZ" for purposes of evaluation. Additionally, we tested CAPES' recent suggestion that the area of Ecology would represent a fourth field of research compatible with the former three. Our results indicate that this system of classification is inappropriate as a guideline for publication improvement, with approximately one third of the journals changing their strata between years. We also demonstrate that the citation profile of Zoology is distinct from those of Botany and Oceanography. Finally, we show that Ecology shows an IF that is significantly different from those of Botany, Oceanography, and Zoology, and that grouping these fields together would be particularly detrimental to Zoology. We conclude that the use of only one parameter of analysis for the stratification of journals, i.e., the Impact Factor calculated for a comparatively small number of journals, fails to evaluate with accuracy the pattern of publication present in Zoology, Botany, and Oceanography. While such simplified procedure might appeals to our sense of objectivity, it dismisses any real attempt to evaluate with clarity the merit embedded in at least three very distinct aspects of scientific practice, namely: productivity, quality, and specificity.

  19. Multilevel resolution demonstration of the utility of C4ISR

    Science.gov (United States)

    Fall, Thomas C.; Plotz, Gary A.

    2001-09-01

    With the development of new C41SR paradigms like the Joint Battle-space Info-sphere (JBI), the High Level Architecture (HLA) and the integration of large simulations like JWARS- JMASS into a distributed synthetic battle-space the requirement to develop new and innovative mixed resolution modeling techniques is more critical than ever before. Analyzing C4ISR utility ahs historically been an issue because there has not been a clear paradigm like force on force attrition is for a combat event. Rather the effects of C4ISR express themselves by modifying the force on force parameters. But by how much is an area of little consensus. We will discuss an approach, which uses the Dynamic Focusing Architecture (DFA) tool, recently developed for AFRL to help navigate these contentious waters.

  20. Interoperability technology assessment for joint C4ISR systems

    OpenAIRE

    Berzins, Valdis Andris; Luqi; Shultes, Bruce C.; Guo, Jiang; Allen, Jim; Cheng, Ngom; Gee, Karen; Nyugen, Tom; Stierna, Eria

    1999-01-01

    This study characterizes and assesses alternative approaches to software component interoperability in distributed environments typical of C4ISR systems. Interoperability is the ability of systems to provide services to and accept services from other systems, and to use the services so exchanged to enable them to operate effectively together. This study characterizes and assesses alternative approaches to software component interoperability in distributed environments. Candidate approaches in...

  1. Access control within military C4ISR systems

    Science.gov (United States)

    Maschino, Mike

    2003-07-01

    Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) tactical battlefield systems must provide the right information and resources to the right individuals at the right time. At the same time, the C4ISR system must enforce access controls to prevent the wrong individuals from obtaining sensitive information, or consuming scarce resources. Because lives, missions and property depend upon them, these access control mechanisms must be effective, reliable, efficient and flexible. The mechanisms employed must suit the nature of the items that are to be protected, as well as the varieties of access policies that must be enforced, and the types of access that will be made to these items. Some access control technologies are inherently centralized, while others are suitable for distributed implementation. The C4ISR architect must select from among the available technologies a combination of mechanisms that eases the burden of policy administration, but is inherently survivable, accurate, resource efficient, and which provides low latency. This paper explores various alternative access enforcement mechanisms, and assesses their effectiveness in managing policy-driven access control within the battlespace.

  2. The potential of C4 grasses for cellulosic biofuel production

    Directory of Open Access Journals (Sweden)

    Tim eWeijde

    2013-05-01

    Full Text Available With the advent of biorefinery technologies enabling plant biomass to be processed into biofuel, many researchers set out to study and improve candidate biomass crops. Many of these candidates are C4 grasses, characterized by a high productivity and resource use efficiency. In this review the potential of five C4 grasses as lignocellulose feedstock for biofuel production is discussed. These include three important field crops - maize, sugarcane and sorghum - and two undomesticated perennial energy grasses - miscanthus and switchgrass. Although all these grasses are high yielding, they produce different products. While miscanthus and switchgrass are exploited exclusively for lignocellulosic biomass, maize, sorghum and sugarcane are dual-purpose crops. It is unlikely that all the prerequisites for the sustainable and economic production of biomass for a global cellulosic biofuel industry will be fulfilled by a single crop. High and stable yields of lignocellulose are required in diverse environments worldwide, to sustain a year-round production of biofuel. A high resource use efficiency is indispensable to allow cultivation with minimal inputs of nutrients and water and the exploitation of marginal soils for biomass production. Finally, the lignocellulose composition of the feedstock should be optimized to allow its efficient conversion into biofuel and other by-products. Breeding for these objectives should encompass diverse crops, to meet the demands of local biorefineries and provide adaptability to different environments. Collectively, these C4 grasses are likely to play a central role in the supply of lignocellulose for the cellulosic ethanol industry. Moreover, as these species are evolutionary closely related, advances in each of these crops will expedite improvements in the other crops. This review aims to provide an overview of their potential, prospects and research needs as lignocellulose feedstocks for the commercial production of

  3. An approach for characterising a coalition C4ISR architecture

    Science.gov (United States)

    Jakobsson, Aase; Main, Paul

    2004-07-01

    There is increasingly a requirement for new capabilities to operate in a coalition rather than just within a country's own network centric (or platform centric) force. This paper discusses an approach for characterising a coalition C4ISR architecture in the future timeframe, for the purpose of analysing information exchange and interoperability issues that may occur when introducing a new system into a mix of future systems and legacy systems with the requirement to ensure NCW readiness. To characterise the C4ISR environment two timeframes, 2010 and 2020, are envisaged for the architecture. These two timeframes represent different types of models of the architecture. The closer timeframe represents a physical model of the C4ISR environment, with the assumption that the time is no further out than what is covered by defence capability plans and knowledge about legacy systems that will still be in use. Its purpose is to allow constructive information exchange with potential future coalition partners regarding interfaces and interoperability. The distant timeframe is set beyond the plans for future capability development. However, known capabilities will still be present at that time. This timeframe represents a requirement and functional concepts model of the architecture. Its purpose is to allow the development of new concepts perhaps more aligned to NCW thinking. The approach utilises systems engineering as a basis for the process and a combination of architecture products for documentation. The work is supported by the use of a collaborative engineering environment and a number of common systems engineering tools such as DOORS, CORE and Systems Architect.

  4. Bayesian truthing as experimental verification of C4ISR sensors

    Science.gov (United States)

    Jannson, Tomasz; Forrester, Thomas; Romanov, Volodymyr; Wang, Wenjian; Nielsen, Thomas; Kostrzewski, Andrew

    2015-05-01

    In this paper, the general methodology for experimental verification/validation of C4ISR and other sensors' performance, is presented, based on Bayesian inference, in general, and binary sensors, in particular. This methodology, called Bayesian Truthing, defines Performance Metrics for binary sensors in: physics, optics, electronics, medicine, law enforcement, C3ISR, QC, ATR (Automatic Target Recognition), terrorism related events, and many others. For Bayesian Truthing, the sensing medium itself is not what is truly important; it is how the decision process is affected.

  5. de la fotosíntesis C4

    Directory of Open Access Journals (Sweden)

    J. C. Raya-Pérez

    2008-01-01

    Full Text Available La fotosíntesis C4 surgió hace unos 7-5 millones de años y tiene un origen polifilético. La disminución en la concentración atmosférica de CO2 a menos de 500 partes por millón (ppm propició la aparición de un mecanismo para concentrar este gas en la zona donde actúa la Rubisco (ribulosa bifosfato carboxilasa/oxigenasa, evitando así su actividad de oxigenasa. El análisis de los genes que codifican para las enzimas usadas en la vía C4, así como la caracterización bioquímica de algunas de estas enzimas, permiten entrever algunos de los cambios que han sufrido a fin de adaptarse a una nueva función, la de concentrar el CO2 a fin de que sea utilizado por la Rubisco.

  6. 118-C-4 Horizontal Rod Cave characterization plan

    International Nuclear Information System (INIS)

    1997-08-01

    This characterization plan provides instructions for obtaining and analyzing samples for waste designation and disposal. The 118-C-4 Horizontal Rod Cave is located in the 100-C Area about 328 ft (100 m) southeast of the 105-C Reactor (Figure 1). The 118-C-4 Horizontal Rod Cave (Figure 2) is a reinforced concrete bunker approximately 70- ft (21.3-m) long, 7-ft (2.1-m) high, and 12-ft (3.6-m) wide, with triangular-shaped concrete ends 3-ft (0.9-m) high. The rod cave was used to store radiologically contaminated control-rod tips. If control rod tips are present, release of control rod activation products will not change expectations with respect to principal contaminants. The north portion of the cave is empty and the south portion contains two aluminum tubes that may contain rod tips (Figure 3). The caves are contaminated with activation and fission products (e.g., 60Co and 137Cs) common to the 100 Areas (see Appendix for data). Dose rates up to 0.7 mR/hr were measured in the south cave and 0.5 mR/hr in the north cave during an inspection of the facility in December 1996

  7. Yersinia pestis Ail recruitment of C4b-binding protein leads to factor I-mediated inactivation of covalently and noncovalently bound C4b.

    Science.gov (United States)

    Ho, Derek K; Skurnik, Mikael; Blom, Anna M; Meri, Seppo

    2014-03-01

    The outer membrane protein Ail of Yersinia pestis mediates several virulence functions, including serum resistance. Here, we demonstrate that Ail binds C4b-binding protein (C4BP), the primary fluid-phase regulator of the classical and lectin pathways. Non-covalent binding of C4 and C4b to Ail was also observed. C4BP bound to Ail can act as a cofactor to the serine protease factor I (fI) in the cleavage of fluid-phase C4b. Employing a panel of C4BP alpha-chain mutants, we observed that the absence of complement control protein domain 6 and 8 reduced binding to Ail. Immunoblot analysis of normal human serum (NHS)-treated bacteria revealed minimal C4b alpha'-chain complexes with bacterial outer membrane targets. Addition of the anti-C4BP monoclonal antibody MK104 to NHS restored C4b-alpha' chain target complexes, suggesting that C4b binds covalently to targets on the Y. pestis surface. C4b bound to Ail noncovalently was also cleaved in a C4BP and fI-dependent manner, leaving the C4c fragment bound to Ail. MK104 also prevented the cleavage of noncovalently bound C4b. Collectively, these data suggest that when C4BP is bound to Ail, fI can cleave and inactivate C4b that has bound covalently to bacterial surface structures as well as C4b bound noncovalently to Ail. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. The effect of NADP-dependent malic enzyme expression and anaerobic C4 metabolism in Escherichia coli compared with other anaplerotic enzymes.

    Science.gov (United States)

    Kwon, Y-D; Kwon, O-H; Lee, H-S; Kim, P

    2007-12-01

    To understand the modification of C4-metabolism under anaerobic glycolysis condition by overexpressing anaplerotic enzymes, which mediating carboxylation of C3 into C4 metabolites, in Escherichia coli. Anaplerotic NADP-dependent malic enzyme (MaeB), as well as the other anaplerotic enzymes, including phosphoenolpyruvate carboxylase (Ppc), phosphoenolpyruvate carboxykinase (Pck) and NAD-dependent malic enzyme (MaeA), were artificially expressed and their C4 metabolism was compared in E. coli. Increasing MaeB expression enhanced the production of C4 metabolites by 2.4 times compared to the wild-type strain in anaerobic glucose medium with bicarbonate supplementation. In MaeB expression, C4 metabolism by supplementing 10 g l(-1) of NaHCO(3) was three times than that by no supplementation, which showed the greatest response to increased CO(2) availability among the tested anaplerotic enzyme expressions. The higher C4 metabolism was achieved in E. coli expressing increased levels of the NADPH-dependent MaeB. The greatest increase in the C4 metabolite ratio compared to the other tested enzymes were also found in E. coli with enhanced MaeB expression as CO(2) availability increased. The higher C4 metabolites and related biomolecule productions can be accomplished by MaeB overexpression in metabolically engineered E. coli.

  9. Artificial Consciousness or Artificial Intelligence

    OpenAIRE

    Spanache Florin

    2017-01-01

    Artificial intelligence is a tool designed by people for the gratification of their own creative ego, so we can not confuse conscience with intelligence and not even intelligence in its human representation with conscience. They are all different concepts and they have different uses. Philosophically, there are differences between autonomous people and automatic artificial intelligence. This is the difference between intelligence and artificial intelligence, autonomous versus a...

  10. Low copy numbers of complement C4 and homozygous deficiency of C4A may predispose to severe disease and earlier disease onset in patients with systemic lupus erythematosus.

    Science.gov (United States)

    Jüptner, M; Flachsbart, F; Caliebe, A; Lieb, W; Schreiber, S; Zeuner, R; Franke, A; Schröder, J O

    2018-04-01

    Objectives Low copy numbers and deletion of complement C4 genes are potent risk factors for systemic lupus erythematosus (SLE). However, it is not known whether this genetic association affects the clinical outcome. We investigated C4 copy number variation and its relationship to clinical and serological features in a Northern European lupus cohort. Methods We genotyped the C4 gene locus using polymerase chain reaction (PCR)-based TaqMan assays in 169 patients with SLE classified according to the 1997 revised American College of Rheumatology (ACR) criteria and in 520 matched controls. In the patient group the mean C4 serum protein concentrations nephelometrically measured during a 12-month period prior to genetic analysis were compared to C4 gene copy numbers. Severity of disease was classified according to the intensity of the immunosuppressive regimens applied and compared to C4 gene copy numbers, too. In addition, we performed a TaqMan based analysis of three lupus-associated single-nucleotide polymorphisms (SNPs) located inside the major histocompatibility complex (MHC) to investigate the independence of complement C4 in association with SLE. Results Homozygous deficiency of the C4A isotype was identified as the strongest risk factor for SLE (odds ratio (OR) = 5.329; p = 7.7 × 10 -3 ) in the case-control comparison. Moreover, two copies of total C4 were associated with SLE (OR = 3.699; p = 6.8 × 10 -3 ). C4 serum levels were strongly related to C4 gene copy numbers in patients, the mean concentration ranging from 0.110 g/l (two copies) to 0.256 g/l (five to six copies; p = 4.9 × 10 -6 ). Two copies of total C4 and homozygous deletion of C4A were associated with a disease course requiring cyclophosphamide therapy (OR = 4.044; p = 0.040 and OR = 5.798; p = 0.034, respectively). Homozygous deletion of C4A was associated with earlier onset of SLE (median 24 vs. 34 years; p = 0.019) but not significant after

  11. Artificial intelligence

    CERN Document Server

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  12. Superhydrophobic treatment using atmospheric-pressure He/C4F8 plasma for buoyancy improvement

    Science.gov (United States)

    Noh, Sooryun; Moon, A.-Young; Moon, Se Youn

    2015-04-01

    A superhydrophobic miniature boat was fabricated with aluminum alloy plates treated with atmospheric-pressure helium (He)/octafluorocyclobutane (C4F8) plasma using 13.56 MHz rf power. When only 0.13% C4F8 was added to He gas, the contact angle of the surface increased to 140° and the surface showed superhydrophobic properties. On the basis of chemical and morphological analyses, fluorinated functional groups (CF, CF2, and CF3) and nano-/micro-sized particles were detected on the Al surface. These features brought about superhydrophobicity similar to the lotus effect. While the miniature boat, assembled with plasma-treated plates, was immersed in water, a layer of air (i.e., a plastron) surrounded the superhydrophobic surfaces. This effect contributed to the development of a 4.7% increase in buoyancy. In addition, the superhydrophobic properties lasted for two months under the submerged condition. These results demonstrate that treatment with atmospheric-pressure He/C4F8 plasma is a promising method of improving the load capacity and antifouling properties, and reducing the friction of marine ships through a fast and low-cost superhydrophobic treatment process.

  13. Artificial Reefs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  14. Artificial Metalloenzymes

    NARCIS (Netherlands)

    Rosati, Fiora; Roelfes, Gerard

    Artificial metalloenzymes have emerged as a promising approach to merge the attractive properties of homogeneous catalysis and biocatalysis. The activity and selectivity, including enantioselectivity, of natural metalloenzymes are due to the second coordination sphere interactions provided by the

  15. The clinical and genomic significance of donor-specific antibody-positive/C4d-negative and donor-specific antibody-negative/C4d-negative transplant glomerulopathy.

    Science.gov (United States)

    Hayde, Nicole; Bao, Yi; Pullman, James; Ye, Bin; Calder, R Brent; Chung, Monica; Schwartz, Daniel; Lubetzky, Michelle; Ajaimy, Maria; de Boccardo, Graciela; Akalin, Enver

    2013-12-01

    This study investigated the mechanisms involved in development of donor-specific antibody (DSA) and/or C4d-negative transplant glomerulopathy (TGP) by allograft gene expression profiles using microarrays. This cohort study was conducted in kidney transplant recipients. Patients were eligible for inclusion if they required a clinically indicated biopsy at any time point after their transplant. They were then classified according to their histopathology findings and DSA and C4d results. Eighteen chronic antibody-mediated rejection (CAMR), 14 DSA+/C4d- TGP, 25 DSA-/C4d- TGP, and 47 nonspecific interstitial fibrosis/tubular atrophy (IFTA) biopsy specimens were identified. In a subset of patients from the study population, biopsy specimens in each group and normal transplant kidney specimens were analyzed with Affymetrix Human Gene 1.0 ST Arrays. The mean sum score of glomerulitis and peritubular capillaritis increased from 0.28±0.78 in IFTA specimens to 0.75±0.85 in DSA-/C4d- TGP specimens, 1.71±1.49 in DSA+/C4d-/TGP specimens, and 2.11±1.74 in CAMR specimens (PTGP specimens (14.3%), and DSA-/C4d- TGP specimens (16%) (P=0.01). With use of microarrays, comparison of the gene expression profiles of DSA-/C4d- TGP specimens with glomerulitis + peritubular capillaritis scores > 0 to normal and IFTA biopsy specimens revealed higher expression of quantitative cytotoxic T cell-associated transcripts (QCAT). However, both CAMR and DSA+/C4d- TGP specimens had higher expression of not only QCAT but also IFN-γ and rejection-induced, constitutive macrophage-associated, natural killer cell-associated, and DSA-selective transcripts. Endothelial cell-associated transcript expression was upregulated only in CAMR biopsy specimens. These results suggested that DSA+/C4d- TGP biopsy specimens may be classified as CAMR. In contrast, DSA-/C4d- TGP specimens showed increased cytotoxic T cell-associated transcripts, suggesting T cell activation as a mechanism of injury.

  16. The Clinical and Genomic Significance of Donor-Specific Antibody–Positive/C4d-Negative and Donor-Specific Antibody–Negative/C4d-Negative Transplant Glomerulopathy

    Science.gov (United States)

    Hayde, Nicole; Bao, Yi; Pullman, James; Ye, Bin; Calder, R. Brent; Chung, Monica; Schwartz, Daniel; Lubetzky, Michelle; Ajaimy, Maria; de Boccardo, Graciela

    2013-01-01

    Summary Background This study investigated the mechanisms involved in development of donor-specific antibody (DSA) and/or C4d-negative transplant glomerulopathy (TGP) by allograft gene expression profiles using microarrays. Design, Setting, Participants, & Measurements This cohort study was conducted in kidney transplant recipients. Patients were eligible for inclusion if they required a clinically indicated biopsy at any time point after their transplant. They were then classified according to their histopathology findings and DSA and C4d results. Eighteen chronic antibody-mediated rejection (CAMR), 14 DSA+/C4d− TGP, 25 DSA−/C4d− TGP, and 47 nonspecific interstitial fibrosis/tubular atrophy (IFTA) biopsy specimens were identified. In a subset of patients from the study population, biopsy specimens in each group and normal transplant kidney specimens were analyzed with Affymetrix Human Gene 1.0 ST Arrays. Results The mean sum score of glomerulitis and peritubular capillaritis increased from 0.28±0.78 in IFTA specimens to 0.75±0.85 in DSA−/C4d− TGP specimens, 1.71±1.49 in DSA+/C4d−/TGP specimens, and 2.11±1.74 in CAMR specimens (PTGP specimens (14.3%), and DSA−/C4d− TGP specimens (16%) (P=0.01). With use of microarrays, comparison of the gene expression profiles of DSA−/C4d− TGP specimens with glomerulitis + peritubular capillaritis scores > 0 to normal and IFTA biopsy specimens revealed higher expression of quantitative cytotoxic T cell–associated transcripts (QCAT). However, both CAMR and DSA+/C4d− TGP specimens had higher expression of not only QCAT but also IFN-γ and rejection-induced, constitutive macrophage-associated, natural killer cell–associated, and DSA-selective transcripts. Endothelial cell–associated transcript expression was upregulated only in CAMR biopsy specimens. Conclusions These results suggested that DSA+/C4d− TGP biopsy specimens may be classified as CAMR. In contrast, DSA−/C4d− TGP specimens showed

  17. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie......-containing sweeteners. The purpose of this review is to summarize the current evidence on the effect of artificial sweeteners on body weight, appetite, and risk markers for diabetes and CVD in humans....

  18. Identification of Photosynthesis-Associated C4 Candidate Genes through Comparative Leaf Gradient Transcriptome in Multiple Lineages of C3 and C4 Species

    Science.gov (United States)

    Ding, Zehong; Weissmann, Sarit; Wang, Minghui; Du, Baijuan; Huang, Lei; Wang, Lin; Tu, Xiaoyu; Zhong, Silin; Myers, Christopher; Brutnell, Thomas P.; Sun, Qi; Li, Pinghua

    2015-01-01

    Leaves of C4 crops usually have higher radiation, water and nitrogen use efficiencies compared to the C3 species. Engineering C4 traits into C3 crops has been proposed as one of the most promising ways to repeal the biomass yield ceiling. To better understand the function of C4 photosynthesis, and to identify candidate genes that are associated with the C4 pathways, a comparative transcription network analysis was conducted on leaf developmental gradients of three C4 species including maize, green foxtail and sorghum and one C3 species, rice. By combining the methods of gene co-expression and differentially co-expression networks, we identified a total of 128 C4 specific genes. Besides the classic C4 shuttle genes, a new set of genes associated with light reaction, starch and sucrose metabolism, metabolites transportation, as well as transcription regulation, were identified as involved in C4 photosynthesis. These findings will provide important insights into the differential gene regulation between C3 and C4 species, and a good genetic resource for establishing C4 pathways in C3 crops. PMID:26465154

  19. Artificial intelligence

    International Nuclear Information System (INIS)

    Perret-Galix, D.

    1992-01-01

    A vivid example of the growing need for frontier physics experiments to make use of frontier technology is in the field of artificial intelligence and related themes. This was reflected in the second international workshop on 'Software Engineering, Artificial Intelligence and Expert Systems in High Energy and Nuclear Physics' which took place from 13-18 January at France Telecom's Agelonde site at La Londe des Maures, Provence. It was the second in a series, the first having been held at Lyon in 1990

  20. Artificial Intelligence

    CERN Document Server

    Warwick, Kevin

    2011-01-01

    if AI is outside your field, or you know something of the subject and would like to know more then Artificial Intelligence: The Basics is a brilliant primer.' - Nick Smith, Engineering and Technology Magazine November 2011 Artificial Intelligence: The Basics is a concise and cutting-edge introduction to the fast moving world of AI. The author Kevin Warwick, a pioneer in the field, examines issues of what it means to be man or machine and looks at advances in robotics which have blurred the boundaries. Topics covered include: how intelligence can be defined whether machines can 'think' sensory

  1. Effects of low atmospheric CO2 and elevated temperature during growth on the gas exchange responses of C3, C3-C4 intermediate, and C4 species from three evolutionary lineages of C4 photosynthesis.

    Science.gov (United States)

    Vogan, Patrick J; Sage, Rowan F

    2012-06-01

    This study evaluates acclimation of photosynthesis and stomatal conductance in three evolutionary lineages of C(3), C(3)-C(4) intermediate, and C(4) species grown in the low CO(2) and hot conditions proposed to favo r the evolution of C(4) photosynthesis. Closely related C(3), C(3)-C(4), and C(4) species in the genera Flaveria, Heliotropium, and Alternanthera were grown near 380 and 180 μmol CO(2) mol(-1) air and day/night temperatures of 37/29°C. Growth CO(2) had no effect on photosynthetic capacity or nitrogen allocation to Rubisco and electron transport in any of the species. There was also no effect of growth CO(2) on photosynthetic and stomatal responses to intercellular CO(2) concentration. These results demonstrate little ability to acclimate to low CO(2) growth conditions in closely related C(3) and C(3)-C(4) species, indicating that, during past episodes of low CO(2), individual C(3) plants had little ability to adjust their photosynthetic physiology to compensate for carbon starvation. This deficiency could have favored selection for more efficient modes of carbon assimilation, such as C(3)-C(4) intermediacy. The C(3)-C(4) species had approximately 50% greater rates of net CO(2) assimilation than the C(3) species when measured at the growth conditions of 180 μmol mol(-1) and 37°C, demonstrating the superiority of the C(3)-C(4) pathway in low atmospheric CO(2) and hot climates of recent geological time.

  2. Potential Hazards Relating to Pyrolysis of c-C4F8O, n-C4F10 and c-C4F8 in selected gaseous diffusion plant operations

    International Nuclear Information System (INIS)

    Trowbridge, L.D.

    2000-01-01

    As part of a program intended to replace the present evaporative coolant at the gaseous diffusion plants (GDPs) with a non-ozone-depleting alternate, a series of investigations of the suitability of candidate substitutes is under way. This report summarizes studies directed at estimating the chemical and thermal stability of three candidate coolants, c-C 4 F 8 O, n-C 4 F 10 and c-C 4 4F 8 , in a few specific environments to be found in gaseous diffusion plant operations

  3. Phylogeny of C4-photosynthesis enzymes based on algal transcriptomic and genomic data supports an archaeal/proteobacterial origin and multiple duplication for most C4-related genes.

    Directory of Open Access Journals (Sweden)

    Shan Chi

    Full Text Available Both Calvin-Benson-Bassham (C3 and Hatch-Slack (C4 cycles are most important autotrophic CO2 fixation pathways on today's Earth. C3 cycle is believed to be originated from cyanobacterial endosymbiosis. However, studies on evolution of different biochemical variants of C4 photosynthesis are limited to tracheophytes and origins of C4-cycle genes are not clear till now. Our comprehensive analyses on bioinformatics and phylogenetics of novel transcriptomic sequencing data of 21 rhodophytes and 19 Phaeophyceae marine species and public genomic data of more algae, tracheophytes, cyanobacteria, proteobacteria and archaea revealed the origin and evolution of C4 cycle-related genes. Almost all of C4-related genes were annotated in extensive algal lineages with proteobacterial or archaeal origins, except for phosphoenolpyruvate carboxykinase (PCK and aspartate aminotransferase (AST with both cyanobacterial and archaeal/proteobacterial origin. Notably, cyanobacteria may not possess complete C4 pathway because of the flawed annotation of pyruvate orthophosphate dikinase (PPDK genes in public data. Most C4 cycle-related genes endured duplication and gave rise to functional differentiation and adaptation in different algal lineages. C4-related genes of NAD-ME (NAD-malic enzyme and PCK subtypes exist in most algae and may be primitive ones, while NADP-ME (NADP-malic enzyme subtype genes might evolve from NAD-ME subtype by gene duplication in chlorophytes and tracheophytes.

  4. Complement factors C4 and C3 are down regulated in response to short term overfeeding in healthy young men

    DEFF Research Database (Denmark)

    Foghmar, Caroline; Brøns, Charlotte; Pilely, Katrine

    2017-01-01

    -days HFO by a hyperinsulinemic-euglycemic-clamp. Circulating C4, C3, ficolins, mannose-binding-lectin, complement activation products C3bc, terminal complement complex (TCC) and complement activation capacity were determined using turbidimetry and ELISA. HFO induced peripheral insulin resistance in LBW...... individuals only, while both groups had the same degree of hepatic insulin resistance after HFO. Viewing all individuals circulating levels of C4, C3, C3bc, TCC and complement activation capacity decreased paradoxically along the development of insulin resistance after HFO (P = 0.0015, P

  5. Artificial Intelligence.

    Science.gov (United States)

    Wash, Darrel Patrick

    1989-01-01

    Making a machine seem intelligent is not easy. As a consequence, demand has been rising for computer professionals skilled in artificial intelligence and is likely to continue to go up. These workers develop expert systems and solve the mysteries of machine vision, natural language processing, and neural networks. (Editor)

  6. The ultraviolet photochemistry of diacetylene - Direct detection of primary products of the metastable C4H2* + C4H2 reaction

    Science.gov (United States)

    Bandy, Ralph E.; Lakshminarayan, Chitra; Frost, Rex K.; Zwier, Timothy S.

    1993-01-01

    The products of diacetylene's ultraviolet photochemistry over the 245-220 nm region were directly determined in experiments where C4H2 was excited within a small reaction tube attached to a pulsed nozzle. The products formed in the collisions of C4H2* with C4H2 were subsequently ionized by vacuum UV radiation (at 118 nm) in the ion source of a time-of-flight mass spectrometer. It was found that the reaction of C4H2* with C4H2 produces C6H2 (+C2H2), C8H2 (+2H,H2), and C8H3 (+H), confirming the results of Glicker and Okabe (1987). Under certain conditions, secondary products were observed. Mechanisms for the observed reactions are proposed.

  7. Revealing diversity in structural and biochemical forms of C4 photosynthesis and a C3-C4 intermediate in genus Portulaca L. (Portulacaceae).

    Science.gov (United States)

    Voznesenskaya, Elena V; Koteyeva, Nuria K; Edwards, Gerald E; Ocampo, Gilberto

    2010-08-01

    Portulacaceae is one of 19 families of terrestrial plants in which species having C(4) photosynthesis have been found. Representative species from major clades of the genus Portulaca were studied to characterize the forms of photosynthesis structurally and biochemically. The species P. amilis, P. grandiflora, P. molokiniensis, P. oleracea, P. pilosa, and P. umbraticola belong to the subgenus Portulaca and are C(4) plants based on leaf carbon isotope values, Kranz anatomy, and expression of key C(4) enzymes. Portulaca umbraticola, clade Umbraticola, is NADP-malic enzyme (NADP-ME)-type C(4) species, while P. oleracea and P. molokiniensis in clade Oleracea are NAD-ME-type C(4) species, all having different forms of Atriplicoid-type leaf anatomy. In clade Pilosa, P. amilis, P. grandiflora, and P. pilosa are NADP-ME-type C(4) species. They have Pilosoid-type anatomy in which Kranz tissues enclose peripheral vascular bundles with water storage in the centre of the leaf. Portulaca cf. bicolor, which belongs to subgenus Portulacella, is an NADP-ME C(4) species with Portulacelloid-type anatomy; it has well-developed Kranz chlorenchyma surrounding lateral veins distributed in one plane under the adaxial epidermis with water storage cells underneath. Portulaca cryptopetala (clade Oleracea), an endemic species from central South America, was identified as a C(3)-C(4) based on its intermediate CO(2) compensation point and selective localization of glycine decarboxylase of the photorespiratory pathway in mitochondria of bundle sheath cells. The C(4) Portulaca species which were examined also have cotyledons with Kranz-type anatomy, while the stems of all species have C(3)-type photosynthetic cells. The results indicate that multiple structural and biochemical forms of C(4) photosynthesis evolved in genus Portulaca.

  8. Revealing diversity in structural and biochemical forms of C4 photosynthesis and a C3–C4 intermediate in genus Portulaca L. (Portulacaceae)

    Science.gov (United States)

    Voznesenskaya, Elena V.; Koteyeva, Nuria K.; Edwards, Gerald E.; Ocampo, Gilberto

    2010-01-01

    Portulacaceae is one of 19 families of terrestrial plants in which species having C4 photosynthesis have been found. Representative species from major clades of the genus Portulaca were studied to characterize the forms of photosynthesis structurally and biochemically. The species P. amilis, P. grandiflora, P. molokiniensis, P. oleracea, P. pilosa, and P. umbraticola belong to the subgenus Portulaca and are C4 plants based on leaf carbon isotope values, Kranz anatomy, and expression of key C4 enzymes. Portulaca umbraticola, clade Umbraticola, is NADP-malic enzyme (NADP-ME)-type C4 species, while P. oleracea and P. molokiniensis in clade Oleracea are NAD-ME-type C4 species, all having different forms of Atriplicoid-type leaf anatomy. In clade Pilosa, P. amilis, P. grandiflora, and P. pilosa are NADP-ME-type C4 species. They have Pilosoid-type anatomy in which Kranz tissues enclose peripheral vascular bundles with water storage in the centre of the leaf. Portulaca cf. bicolor, which belongs to subgenus Portulacella, is an NADP-ME C4 species with Portulacelloid-type anatomy; it has well-developed Kranz chlorenchyma surrounding lateral veins distributed in one plane under the adaxial epidermis with water storage cells underneath. Portulaca cryptopetala (clade Oleracea), an endemic species from central South America, was identified as a C3–C4 based on its intermediate CO2 compensation point and selective localization of glycine decarboxylase of the photorespiratory pathway in mitochondria of bundle sheath cells. The C4 Portulaca species which were examined also have cotyledons with Kranz-type anatomy, while the stems of all species have C3-type photosynthetic cells. The results indicate that multiple structural and biochemical forms of C4 photosynthesis evolved in genus Portulaca. PMID:20591900

  9. Using SPIRAL (Single Pollen Isotope Ratio AnaLysis) to estimate C 3- and C 4-grass abundance in the paleorecord

    Science.gov (United States)

    Nelson, David M.; Hu, Feng Sheng; Scholes, Daniel R.; Joshi, Neeraj; Pearson, Ann

    2008-05-01

    C 3 and C 4 grasses differ greatly in their responses to environmental controls and influences on biogeochemical processes (e.g. water, carbon, and nutrient cycling). Difficulties in distinguishing between these two functional groups of grasses have hindered paleoecological studies of grass-dominated ecosystems. Stable carbon isotopic analysis of individual grains of grass pollen using a spooling-wire microcombustion device interfaced with an isotope-ratio mass spectrometer holds promise for improving C 3 and C 4 grass reconstructions. This technique, SPIRAL (Single Pollen Isotope Ratio AnaLysis), has only been evaluated using pollen of known C 3 and C 4 grasses. To test the ability of SPIRAL to reproduce the abundance of C 3 and C 4 grasses on the landscape, we measured δ13C values of > 1500 individual grains of grass pollen isolated from the surface sediments of ten lakes in areas that span a large gradient of C 3- and C 4-grass abundance, as determined from vegetation surveys. Results indicate a strong positive correlation between the δ13C-based estimates of % C 4-grass pollen and the abundance of C 4 grasses on the landscape. The % C 4-grass pollen slightly underestimates the actual abundance of C 4 grasses at sites with high proportions of C 4 grasses, which can be corrected using regression analysis. Comparison of the % C 4-grass pollen with C/N and δ13C measurements of bulk organic matter illustrates the distinct advantages of grass-pollen δ13C as a proxy for distinguishing C 3 and C 4 shifts within the grass family. Thus SPIRAL promises to advance our understanding of grassland ecology and evolution.

  10. 26 CFR 1.662(c)-4 - Illustration of the provisions of sections 661 and 662.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Illustration of the provisions of sections 661 and 662. 1.662(c)-4 Section 1.662(c)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Which Distribute Corpus § 1.662(c)-4 Illustration of the provisions of sections 661 and 662. The...

  11. 26 CFR 1.652(c)-4 - Illustration of the provisions of sections 651 and 652.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Illustration of the provisions of sections 651 and 652. 1.652(c)-4 Section 1.652(c)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE....652(c)-4 Illustration of the provisions of sections 651 and 652. The rules applicable to a trust...

  12. Glyphosate Resistance of C3 and C4 Weeds under Rising Atmospheric CO2.

    Science.gov (United States)

    Fernando, Nimesha; Manalil, Sudheesh; Florentine, Singarayer K; Chauhan, Bhagirath S; Seneweera, Saman

    2016-01-01

    The present paper reviews current knowledge on how changes of plant metabolism under elevated CO2 concentrations (e[CO2]) can affect the development of the glyphosate resistance of C3 and C4 weeds. Among the chemical herbicides, glyphosate, which is a non-selective and post-emergence herbicide, is currently the most widely used herbicide in global agriculture. As a consequence, glyphosate resistant weeds, particularly in major field crops, are a widespread problem and are becoming a significant challenge to future global food production. Of particular interest here it is known that the biochemical processes involved in photosynthetic pathways of C3 and C4 plants are different, which may have relevance to their competitive development under changing environmental conditions. It has already been shown that plant anatomical, morphological, and physiological changes under e[CO2] can be different, based on (i) the plant's functional group, (ii) the available soil nutrients, and (iii) the governing water status. In this respect, C3 species are likely to have a major developmental advantage under a CO2 rich atmosphere, by being able to capitalize on the overall stimulatory effect of e[CO2]. For example, many tropical weed grass species fix CO2 from the atmosphere via the C4 photosynthetic pathway, which is a complex anatomical and biochemical variant of the C3 pathway. Thus, based on our current knowledge of CO2 fixing, it would appear obvious that the development of a glyphosate-resistant mechanism would be easier under an e[CO2] in C3 weeds which have a simpler photosynthetic pathway, than for C4 weeds. However, notwithstanding this logical argument, a better understanding of the biochemical, genetic, and molecular measures by which plants develop glyphosate resistance and how e[CO2] affects these measures will be important before attempting to innovate sustainable technology to manage the glyphosate-resistant evolution of weeds under e[CO2]. Such information will be of

  13. Unique photosynthetic phenotypes in Portulaca (Portulacaceae): C3-C4 intermediates and NAD-ME C4 species with Pilosoid-type Kranz anatomy.

    Science.gov (United States)

    Voznesenskaya, Elena V; Koteyeva, Nuria K; Edwards, Gerald E; Ocampo, Gilberto

    2017-01-01

    Portulacaceae is a family that has considerable diversity in photosynthetic phenotypes. It is one of 19 families of terrestrial plants where species having C 4 photosynthesis have been found. Most species in Portulaca are in the alternate-leaved (AL) lineage, which includes one clade (Cryptopetala) with taxa lacking C 4 photosynthesis and three clades having C 4 species (Oleracea, Umbraticola and Pilosa). All three species in the Cryptopetala clade lack Kranz anatomy, the leaves have C 3 -like carbon isotope composition and they have low levels of C 4 cycle enzymes. Anatomical, biochemical and physiological analyses show they are all C 3 -C 4 intermediates. They have intermediate CO 2 compensation points, enrichment of organelles in the centripetal position in bundle sheath (BS) cells, with selective localization of glycine decarboxylase in BS mitochondria. In the three C 4 clades there are differences in Kranz anatomy types and form of malic enzyme (ME) reported to function in C 4 (NAD-ME versus NADP-ME): Oleracea (Atriplicoid, NAD-ME), Umbraticola (Atriplicoid, NADP-ME) and Pilosa (Pilosoid, NADP-ME). Structural and biochemical analyses were performed on Pilosa clade representatives having Pilosoid-type leaf anatomy with Kranz tissue enclosing individual peripheral vascular bundles and water storage in the center of the leaf. In this clade, all species except P. elatior are NADP-ME-type C 4 species with grana-deficient BS chloroplasts and grana-enriched M chloroplasts. Surprisingly, P. elatior has BS chloroplasts enriched in grana and NAD-ME-type photosynthesis. The results suggest photosynthetic phenotypes were probably derived from an ancestor with NADP-ME-type C 4 , with two independent switches to NAD-ME type. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  14. Artificial Intelligence.

    Science.gov (United States)

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve.

  15. Artificial intelligence

    OpenAIRE

    Duda, Antonín

    2009-01-01

    Abstract : Issue of this work is to acquaint the reader with the history of artificial inteligence, esspecialy branch of chess computing. Main attention is given to progress from fifties to the present. The work also deals with fighting chess programs against each other, and against human opponents. The greatest attention is focused on 1997 and duel Garry Kasparov against chess program Deep Blue. The work is divided into chapters according to chronological order.

  16. Artificial Wormhole

    OpenAIRE

    Kirillov, A. A.; Savelova, E. P.

    2012-01-01

    It is shown that recently reported result by the OPERA Collaboration (arXive:1109.4897) of an early arrival time of muon neutrinos with respect to the speed of light in vacuum does not violate standard physical laws. We show that vacuum polarization effects in intensive external fields may form a wormhole-like object. The simplest theory of such an effect is presented and basic principles of formation of an artificial wormhole are also considered.

  17. Artificial vision.

    Science.gov (United States)

    Zarbin, M; Montemagno, C; Leary, J; Ritch, R

    2011-09-01

    A number treatment options are emerging for patients with retinal degenerative disease, including gene therapy, trophic factor therapy, visual cycle inhibitors (e.g., for patients with Stargardt disease and allied conditions), and cell transplantation. A radically different approach, which will augment but not replace these options, is termed neural prosthetics ("artificial vision"). Although rewiring of inner retinal circuits and inner retinal neuronal degeneration occur in association with photoreceptor degeneration in retinitis pigmentosa (RP), it is possible to create visually useful percepts by stimulating retinal ganglion cells electrically. This fact has lead to the development of techniques to induce photosensitivity in cells that are not light sensitive normally as well as to the development of the bionic retina. Advances in artificial vision continue at a robust pace. These advances are based on the use of molecular engineering and nanotechnology to render cells light-sensitive, to target ion channels to the appropriate cell type (e.g., bipolar cell) and/or cell region (e.g., dendritic tree vs. soma), and on sophisticated image processing algorithms that take advantage of our knowledge of signal processing in the retina. Combined with advances in gene therapy, pathway-based therapy, and cell-based therapy, "artificial vision" technologies create a powerful armamentarium with which ophthalmologists will be able to treat blindness in patients who have a variety of degenerative retinal diseases.

  18. The reinvestigation of the kinetics of the metathesis reactions t-C4H9• + HBr (HI) → i-C4H10 + Br• (I•) and of the t-C4H9• free radical thermochemistry.

    Science.gov (United States)

    Leplat, N; Rossi, M J

    2014-07-17

    A reinvestigation of the absolute rate constant of the metathesis reactions t-C4H9• + HBr → i-C4H10 + Br• (1) and t-C4H9• + HI → i-C4H10 + I• (2) was performed thanks to a recently developed apparatus consisting of a Knudsen reactor coupled to detection based on single-photon (VUV) photoionization mass spectrometry (SPIMS). It enables the generation of thermalized hydrocarbon free radicals owing to a source upstream of and external to the Knudsen reactor. The following Arrhenius expressions were obtained: k1 = 5.6(±1.4) × 10(–12) exp(−6.76(±0.94)/(RT)) and k2 = 2.0(±0.6) × 10(–11) exp(−8.48(±0.94)/(RT)) with R = 8.314 J mol(–1) K(–1) over the range 293 to 623 K. The mass balance of the reaction system based on closed shell product detection (CSPD) was checked in order to ensure the accuracy of the used reaction mechanism and as an independent check of k1 and k2. The wall-loss rate constants of the t-butyl free radical, kw(C4H9), were measured and found to be low compared with the corresponding escape rate constant, ke(C4H9), for effusion of t-C4H9• out of the Knudsen reactor. On the basis of the present results, the free radical standard heat of formation ΔfH298°(t-C4H9•) = 44.3 ± 1.7 kJ mol(–1) was obtained when combined with the kinetics of the inverse halogenation reaction taken from the literature and using S298°(t-C4H9•) = 322.2 J K(–1) mol(–1) following a “Third Law” evaluation method. The standard enthalpy for t-butyl free radical is consistent for both the bromination and iodination reactions within the stated uncertainties.

  19. The impact of lower-limb prosthetic limb use in international C4 track para-cycling.

    Science.gov (United States)

    Dyer, Bryce

    2017-09-29

    An investigation was undertaken to ascertain any impact or significance of athletes within the C4 paracycling classification between those who use a lower-limb prostheses and those who do not. A statistical evaluation of event completion time was undertaken to assess C4 cyclists when competing at the World Championships and the Paralympic Games in the 1 km track time trial. The C4 athletes who utilize a prostheses consistently outperformed non-amputees in the C4 classification from 2011 to 2016 on a competition-to-competition basis. However, when the participations were grouped as a whole together and an identified outlier athlete was removed, it was then demonstrated that there was no statistical significance between those who required the use of a lower-limb prostheses to those that did not when either evaluated on a competition-by-competition or on an amputee and non-amputee group-by-group basis (p ≥ 0.05). As a result, this study proposes that those requiring the use of lower-limb prostheses are neither advantaged nor disadvantaged in the C4 classification category when competing in the 1 km time trial at this time. Implications for Rehabilitation This analysis indicates that at this time, there is no evidence to suggest that use of such technology is advantageous in this category or should be seen as controversial. The design of lower-limb prosthetic limb technology in cycling should continue to be developed and optimized unabated. This study begins to address the cited lack of peer-reviewed information regarding paracycling with limb absence available to practitioners.

  20. C-4 Gem-Dimethylated Oleanes of Gymnema sylvestre and Their Pharmacological Activities

    Directory of Open Access Journals (Sweden)

    Giovanni Di Fabio

    2013-12-01

    Full Text Available Gymnema sylvestre R. Br., one of the most important medicinal plants of the Asclepiadaceae family, is a herb distributed throughout the World, predominantly in tropical countries. The plant, widely used for the treatment of diabetes and as a diuretic in Indian proprietary medicines, possesses beneficial digestive, anti-inflammatory, hypoglycemic and anti-helmentic effects. Furthermore, it is believed to be useful in the treatment of dyspepsia, constipation, jaundice, hemorrhoids, cardiopathy, asthma, bronchitis and leucoderma. A literature survey revealed that some other notable pharmacological activities of the plant such as anti-obesity, hypolipidemic, antimicrobial, free radical scavenging and anti-inflammatory properties have been proven too. This paper aims to summarize the chemical and pharmacological reports on a large group of C-4 gem-dimethylated pentacyclic triterpenoids from Gymnema sylvestre.

  1. Sequential unfolding of the two-domain protein Pseudomonas stutzeri cytochrome c(4)

    DEFF Research Database (Denmark)

    Andersen, Niels Højmark; Jensen, Thomas Jon; Nørgaard, Allan

    2002-01-01

    , and different spin states of the oxidised haem groups. We have studied unfolding of oxidised P. stutzeri cyt c(4) induced thermally and by chemical denaturants Horse heart cyt c was a reference molecule. Isothermal unfolding induced by guanidinium chloride and acid was followed by Soret. alpha/beta. and 701-nm...... chloride up to 0.4 M is present. This reflects different chemical action in chemical and thermal unfolding. Acid-induced unfolding kinetics was addressed by pH jumps using diode array stopped-flow techniques, Three kinetic phases in the 701 nm Fe-Met marker band. and four phases in the Soret and alpha/beta......F stutzeri cytochrome c. is a di-haem protein, composed of two globular domains each with His-Met coordinated haem. and a hydrogen bond network between the domains. The domain foldings are highly symmetric but with specific differences including structural differences of ligand coordination...

  2. Fire and fire-adapted vegetation promoted C4 expansion in the late Miocene.

    Science.gov (United States)

    Scheiter, Simon; Higgins, Steven I; Osborne, Colin P; Bradshaw, Catherine; Lunt, Dan; Ripley, Brad S; Taylor, Lyla L; Beerling, David J

    2012-08-01

    Large proportions of the Earth's land surface are covered by biomes dominated by C(4) grasses. These C(4)-dominated biomes originated during the late Miocene, 3-8 million years ago (Ma), but there is evidence that C(4) grasses evolved some 20 Ma earlier during the early Miocene/Oligocene. Explanations for this lag between evolution and expansion invoke changes in atmospheric CO(2), seasonality of climate and fire. However, there is still no consensus about which of these factors triggered C(4) grassland expansion. We use a vegetation model, the adaptive dynamic global vegetation model (aDGVM), to test how CO(2), temperature, precipitation, fire and the tolerance of vegetation to fire influence C(4) grassland expansion. Simulations are forced with late Miocene climates generated with the Hadley Centre coupled ocean-atmosphere-vegetation general circulation model. We show that physiological differences between the C(3) and C(4) photosynthetic pathways cannot explain C(4) grass invasion into forests, but that fire is a crucial driver. Fire-promoting plant traits serve to expand the climate space in which C(4)-dominated biomes can persist. We propose that three mechanisms were involved in C(4) expansion: the physiological advantage of C(4) grasses under low atmospheric CO(2) allowed them to invade C(3) grasslands; fire allowed grasses to invade forests; and the evolution of fire-resistant savanna trees expanded the climate space that savannas can invade. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  3. Promotion of Cyclic Electron Transport Around Photosystem I with the Development of C4 Photosynthesis.

    Science.gov (United States)

    Munekage, Yuri Nakajima; Taniguchi, Yukimi Y

    2016-05-01

    C4 photosynthesis is present in approximately 7,500 species classified into 19 families, including monocots and eudicots. In the majority of documented cases, a two-celled CO2-concentrating system that uses a metabolic cycle of four-carbon compounds is employed. C4 photosynthesis repeatedly evolved from C3 photosynthesis, possibly driven by the survival advantages it bestows in the hot, often dry, and nutrient-poor soils of the tropics and subtropics. The development of the C4 metabolic cycle greatly increased the ATP demand in chloroplasts during the evolution of malic enzyme-type C4 photosynthesis, and the additional ATP required for C4 metabolism may be produced by the cyclic electron transport around PSI. Recent studies have revealed the nature of cyclic electron transport and the elevation of its components during C4 evolution. In this review, we discuss the energy requirements of C3 and C4 photosynthesis, the current model of cyclic electron transport around PSI and how cyclic electron transport is promoted during C4 evolution using studies on the genus Flaveria, which contains a number of closely related C3, C4 and C3-C4 intermediate species. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  4. A Plan for the Application of Artificial Intelligence to DoD Logistics

    Science.gov (United States)

    1989-10-01

    an annual Symposium and Workshop on Artificial Intelligence Applications for Military Logistics at Williamsburg, Virginia. The conference allows the...Staff (GM) AFB = Air Force Base AFLC = Air Force Logistics Command AI = Artificial Intelligence AIAG = Artificial Intelligence Applications Group (DEC...AIASC = Artificial Intelligence Applications Support Center (AFLC) AIBOD = Artificial Intelligence Board of Directors (DEC) AIC = Artificial

  5. Artificial Gravity

    CERN Document Server

    Clément, Gilles

    2007-01-01

    Protecting the health, safety, and performance of exploration-class mission crews against the physiological deconditioning resulting from long-term weightlessness during transit and long-term reduced gravity during surface operations will require effective, multi-system countermeasures. Artificial gravity, which would replace terrestrial gravity with inertial forces generated by rotating the transit vehicle or by short-radius human centrifuge devices within the transit vehicle or surface habitat, has long been considered a potential solution. However, despite its attractiveness as an efficient

  6. Artificial graphites

    International Nuclear Information System (INIS)

    Maire, J.

    1984-01-01

    Artificial graphites are obtained by agglomeration of carbon powders with an organic binder, then by carbonisation at 1000 0 C and graphitization at 2800 0 C. After description of the processes and products, we show how the properties of the various materials lead to the various uses. Using graphite enables us to solve some problems, but it is not sufficient to satisfy all the need of the application. New carbonaceous material open application range. Finally, if some products are becoming obsolete, other ones are being developed in new applications [fr

  7. Functions of OsDof25 in regulation of OsC4PPDK

    NARCIS (Netherlands)

    Zhang, Y.; Verhoeff, N.I.; Chen, Z.; Chen, S.; Wang, M.; Zhu, Z.; Ouwerkerk, P.B.F.

    2015-01-01

    Relative little is known about the functions of the so-called Dof zinc factors in plants. Here we report on the analysis of OsDof25 and show a function in regulation of the important C4 photosynthesis gene, OsC4PPDK in rice. Over-expression of OsDof25 enhanced the expression of OsC4PPDK in transient

  8. Artificial disc and vertebra system: a novel motion preservation device for cervical spinal disease after vertebral corpectomy

    Directory of Open Access Journals (Sweden)

    Jun Dong

    2015-07-01

    Full Text Available OBJECTIVE: To determine the range of motion and stability of the human cadaveric cervical spine after the implantation of a novel artificial disc and vertebra system by comparing an intact group and a fusion group. METHODS: Biomechanical tests were conducted on 18 human cadaveric cervical specimens. The range of motion and the stability index range of motion were measured to study the function and stability of the artificial disc and vertebra system of the intact group compared with the fusion group. RESULTS: In all cases, the artificial disc and vertebra system maintained intervertebral motion and reestablished vertebral height at the operative level. After its implantation, there was no significant difference in the range of motion (ROM of C3-7 in all directions in the non-fusion group compared with the intact group (p>0.05, but significant differences were detected in flexion, extension and axial rotation compared with the fusion group (p<0.05. The ROM of adjacent segments (C3-4, C6-7 of the non-fusion group decreased significantly in some directions compared with the fusion group (p<0.05. Significant differences in the C4-6 ROM in some directions were detected between the non-fusion group and the intact group. In the fusion group, the C4-6 ROM in all directions decreased significantly compared with the intact and non-fusion groups (p<0.01. The stability index ROM (SI-ROM of some directions was negative in the non-fusion group, and a significant difference in SI-ROM was only found in the C4-6 segment of the non-fusion group compared with the fusion group. CONCLUSION: An artificial disc and vertebra system could restore vertebral height and preserve the dynamic function of the surgical area and could theoretically reduce the risk of adjacent segment degeneration compared with the anterior fusion procedure. However, our results should be considered with caution because of the low power of the study. The use of a larger sample should be

  9. Penerapan Algoritma C4.5 untuk Klasifikasi Data Rekam Medis berdasarkan International Classification Diseases (ICD-10

    Directory of Open Access Journals (Sweden)

    Yudha Aditya Fiandra

    2017-10-01

    Full Text Available Abstract The medical record data is the patient's current record of medical records, the medical record data only being data stacked and not traced to generate useful knowledge for the hospital. This study can process the medical record data to classify the disease that occurs in sleeping sickness based on  ICD-10. The method used in this research is C4.5 algorithm method by using attribute of international disease code as attribute of destination label as many as 21 international disease group, that is: A00-B99 up to Z00-Z99. This study yields a decision of the value code, C4.5 code can represent as many as 14 attribute values ​​of disease code objectives and data percentage that read more than 66%. The conclusion of this research is C4.5 algorithm help classify international disease code based on ICD-10 and decision tree making which can give information of any disease that often happened at hospital  Keywords: data mining, classification, C4.5, medical records, ICD-10

  10. Contributions of C3and C4plants to higher trophic levels in an Amazonian savanna.

    Science.gov (United States)

    Magnusson, William E; Carmozina de Araújo, M; Cintra, Renato; Lima, Albertina P; Martinelli, Luiz A; Sanaiotti, Tânia M; Vasconcelos, Heraldo L; Victoria, Reynaldo L

    1999-04-01

    We studied the energy flow from C 3 and C 4 plants to higher trophic levels in a central Amazonian savanna by comparing the carbon stable-isotope ratios of potential food plants to the isotope ratios of species of different consumer groups. All C 4 plants encountered in our study area were grasses and all C 3 plants were bushes, shrubs or vines. Differences in δ 13 C ratios among bushes (x¯ = -30.8, SD = 1.2), vines (x¯ = -30.7, SD = 0.46) and trees (x¯ = -29.7, SD = 1.5) were small. However the mean δ 13 C ratio of dicotyledonous plants (x¯ = -30.4, SD = 1.3) was much more negative than that of the most common grasses (x¯ = -13.4, SD = 0.27). The insect primary consumers had δ 13 C ratios which ranged from a mean of -29.5 (SD = 0.47) for the grasshopper Tropidacris collaris to a mean of -14.7 (SD = 0.56) for a termite (Nasutitermes sp.), a range similar to that of the vegetation. However, the common insectivorous and omnivorous vertebrates had intermediate values for δ 13 C, indicating that carbon from different autotrophic sources mixes rapidly as it moves up the food chain. Despite this mixing, the frogs and lizards generally had higher values of δ 13 C (x¯ = -21.7, SD = 1.6; x¯ = -21.9, SD = 1.8, respectively) than the birds (x¯ = -24.8, SD = 1.8) and the only species of mammal resident in the savanna (x¯ = -25.4), indicating that they are generally more dependent on, or more able to utilise, food chains based on C 4 grasses.

  11. CO2 availability influences hydraulic function of C3 and C4 grass leaves.

    Science.gov (United States)

    Taylor, Samuel H; Aspinwall, Michael J; Blackman, Chris J; Choat, Brendan; Tissue, David T; Ghannoum, Oula

    2018-03-10

    Atmospheric CO2 (ca) has increased since the last glacial period, increasing photosynthetic water use efficiency and improving plant productivity. Evolution of C4 photosynthesis at low ca led to decreased stomatal conductance (gs), which provided an advantage over C3 plants that may be reduced by rising ca. Using controlled environments, we determined how increasing ca affects C4 water use relative to C3 plants. Leaf gas exchange and mass per area (LMA) were measured for four C3 and four C4 annual, crop-related grasses at glacial (200), ambient (400), and super-ambient (640 µmol mol-1) ca. C4 plants had lower gs, which resulted in a water use efficiency advantage at all ca and was broadly consistent with slower stomatal responses to shade, indicating less pressure on leaf water status. At glacial ca, A and LMA were lower for C3 than C4 leaves, and C3 and C4 grasses decreased leaf hydraulic conductance (Kleaf) similarly, but only C4 leaves decreased osmotic potential at turgor-loss. Greater carbon availability in C4 leaves at glacial ca generated different hydraulic adjustment relative to C3 plants. At current and future ca, C4 grasses have advantages over C3 grasses due to lower gs, lower stomatal sensitivity, and higher absolute water use efficiency.

  12. Are changes in sulfate assimilation pathway needed for evolution of C4 photosynthesis?

    Directory of Open Access Journals (Sweden)

    Silke Christine Weckopp

    2015-01-01

    Full Text Available C4 photosynthesis characteristically features a cell-specific localization of enzymes involved in CO2 assimilation in bundle sheath cells or mesophyll cells. Interestingly, enzymes of sulfur assimilation are also specifically present in bundle sheath cells of maize and many other C4 species. This localization, however, could not be confirmed in C4 species of the genus Flaveria. It was, therefore, concluded that the bundle sheath localization of sulfate assimilation occurs only in C4 monocots. However, recently the sulfate assimilation pathway was found coordinately enriched in bundle sheath cells of Arabidopsis, opening new questions about the significance of such cell-specific localization of the pathway. In addition, next generation sequencing revealed expression gradients of many genes from C3 to C4 species and mathematical modelling proposed a sequence of adaptations during the evolutionary path from C3 to C4. Indeed, such gradient, with higher expression of genes for sulfate reduction in C4 species, has been observed within the genus Flaveria. These new tools provide the basis for reexamining the intriguing question of compartmentalization of sulfur assimilation. Therefore, this review summarizes the findings on spatial separation of sulfur assimilation in C4 plants and Arabidopsis, assesses the information on sulfur assimilation provided by the recent transcriptomics data and discusses their possible impact on understanding this interesting feature of plant sulfur metabolism to find out whether changes in sulfate assimilation are part of a general evolutionary trajectory towards C4 photosynthesis.

  13. Involvement of C4 protein of beet severe curly top virus (family Geminiviridae in virus movement.

    Directory of Open Access Journals (Sweden)

    Kunling Teng

    Full Text Available BACKGROUND: Beet severe curly top virus (BSCTV is a leafhopper transmitted geminivirus with a monopartite genome. C4 proteins encoded by geminivirus play an important role in virus/plant interaction. METHODS AND FINDINGS: To understand the function of C4 encoded by BSCTV, two BSCTV mutants were constructed by introducing termination codons in ORF C4 without affecting the amino acids encoded by overlapping ORF Rep. BSCTV mutants containing disrupted ORF C4 retained the ability to replicate in Arabidopsis protoplasts and in the agro-inoculated leaf discs of N. benthamiana, suggesting C4 is not required for virus DNA replication. However, both mutants did not accumulate viral DNA in newly emerged leaves of inoculated N. benthamiana and Arabidopsis, and the inoculated plants were asymptomatic. We also showed that C4 expression in plant could help C4 deficient BSCTV mutants to move systemically. C4 was localized in the cytosol and the nucleus in both Arabidopsis protoplasts and N. benthamiana leaves and the protein appeared to bind viral DNA and ds/ssDNA nonspecifically, displaying novel DNA binding properties. CONCLUSIONS: Our results suggest that C4 protein in BSCTV is involved in symptom production and may facilitate virus movement instead of virus replication.

  14. Complement System and C4d expression in cases of Membranous nephropathy

    Directory of Open Access Journals (Sweden)

    Fabiano Bichuette Custódio

    Full Text Available Abstract Introduction: Membranous nephropathy (MN is one of the major causes of nephrotic syndrome. The complement system plays a key role in the pathophysiology of MN. Objectives: To identify the complement pathway possibly activated in MN cases and correlate the presence of C4d with more severe clinical and histological markers. Methods: Sixty nine cases from renal biopsy with membranous nephropathy were investigated. The presence of C1q was analyzed by direct immunofluorescence; and expression of C4d by immunohistochemistry. Clinical and epidemiological data were obtained upon biopsy request. Results: The presence of focal segmental glomerulosclerosis, global glomerulosclerosis, vascular lesions and tubulointerstitial fibrosis were collected by anatomopathological report. C4d(+ was found in 58 (84%, and C1q(+ was found in 12 (17% of the cases. Twelve patients had C4d(+/C1q(+, 46 had C4d(+/C1q(-, and 11 patients had C4d(-/C1q(-, probably indicating the activation of the classical, lectin and alternative pathways, respectively. Conclusion: C4d was associated with increased interstitial fibrosis, but not with clinical markers of poor prognosis. Through the deposition of C4d and C1q we demonstrated that all complement pathways may be involved in MN, highlighting the lectin pathway. The presence of C4d has been associated with severe tubulointerstitial lesions, but not with clinical markers, or can be taken as a universal marker of all cases of MN.

  15. Generation of baryon excess in SUsub(L)(2) x SUsub(R)(2) x SUsub(c)(4)

    International Nuclear Information System (INIS)

    Deo, B.B.; Prasad, V.B.

    1980-08-01

    We have calculated the magnitude of the cosmological baryon asymmetry in a gauge theory based on the group SUsub(L)(2) x SUsub(R)(2) x SUsub(c)(4) and find that plausible parameters exist in the model to explain the baryon excess with a subunifying mass scale of 10 4 -10 5 GeV. The novel idea used is that the vacuum eats away antimatter through the VEV of the Higgs meson. (author)

  16. Generation of baryon excess in SUsub(L)(2) x SUsub(R)(2) x SUsub(c)(4)

    International Nuclear Information System (INIS)

    Deo, B.B.; Prasad, V.B.

    1981-01-01

    We have calculated the magnitude of the cosmological baryon asymmetry in a gauge theory based on the group SUsub(L)(2) x SUsub(R)(2) x SUsub(c)(4) and find that plausible parameters exist in the model to explain the baryon excess with a subunifying mass scale of 10 4 -10 5 GeV. The novel idea used is that the vacuum eats away antimatter through the VEV of the Higgs meson. (orig.)

  17. Occurrence of C3 nephritic factor and C4 nephritic factor in membranoproliferative glomerulonephritis (MPGN).

    Science.gov (United States)

    Ohi, H; Yasugi, T

    1994-01-01

    One hundred patients diagnosed with hypocomplementaemic MPGN (C3 nephritic factor (C3NeF) and/or C4 nephritic factor (C4NeF). Of those studied, 12 were C3NeF-positive, nine were C4NeF-positive and 10 were positive for both C3NeF and C4NeF. In the 10 patients both C3NeF- and C4NeF-positive, a marked decrease in C3 and C5 levels and a decrease in levels of late components from C6 to C9 were observed. This observation was in contrast to that seen in patients who were either C3NeF- or C4NeF-positive. Patients positive for both C3NeF and C4NeF continued to exhibit hypocomplementaemia after therapy. Immunofluorescent findings revealed heavy C3 immunoglobulin deposits in the 10 patients who were both C3NeF- and C4NeF-positive, whereas no such deposits were found in those patients who were either C3NeF- or C4NeF-positive only. When those patients who were both C3NeF- and C4NeF-positive were compared with those who were either C3NeF- or C4NeF-positive, nephritic syndrome and a poor prognosis were observed more frequently. This study demonstrates a correlation between clinical outcome and hypocomplementaemic MPGN. Further investigations of MPGN as an autoimmune disease are necessary. PMID:8306508

  18. Human pentraxin 3 binds to the complement regulator c4b-binding protein.

    Directory of Open Access Journals (Sweden)

    Anne Braunschweig

    Full Text Available The long pentraxin 3 (PTX3 is a soluble recognition molecule with multiple functions including innate immune defense against certain microbes and the clearance of apoptotic cells. PTX3 interacts with recognition molecules of the classical and lectin complement pathways and thus initiates complement activation. In addition, binding of PTX3 to the alternative complement pathway regulator factor H was shown. Here, we show that PTX3 binds to the classical and lectin pathway regulator C4b-binding protein (C4BP. A PTX3-binding site was identified within short consensus repeats 1-3 of the C4BP α-chain. PTX3 did not interfere with the cofactor activity of C4BP in the fluid phase and C4BP maintained its complement regulatory activity when bound to PTX3 on surfaces. While C4BP and factor H did not compete for PTX3 binding, the interaction of C4BP with PTX3 was inhibited by C1q and by L-ficolin. PTX3 bound to human fibroblast- and endothelial cell-derived extracellular matrices and recruited functionally active C4BP to these surfaces. Whereas PTX3 enhanced the activation of the classical/lectin pathway and caused enhanced C3 deposition on extracellular matrix, deposition of terminal pathway components and the generation of the inflammatory mediator C5a were not increased. Furthermore, PTX3 enhanced the binding of C4BP to late apoptotic cells, which resulted in an increased rate of inactivation of cell surface bound C4b and a reduction in the deposition of C5b-9. Thus, in addition to complement activators, PTX3 interacts with complement inhibitors including C4BP. This balanced interaction on extracellular matrix and on apoptotic cells may prevent excessive local complement activation that would otherwise lead to inflammation and host tissue damage.

  19. Artificial rheotaxis.

    Science.gov (United States)

    Palacci, Jérémie; Sacanna, Stefano; Abramian, Anaïs; Barral, Jérémie; Hanson, Kasey; Grosberg, Alexander Y; Pine, David J; Chaikin, Paul M

    2015-05-01

    Motility is a basic feature of living microorganisms, and how it works is often determined by environmental cues. Recent efforts have focused on developing artificial systems that can mimic microorganisms, in particular their self-propulsion. We report on the design and characterization of synthetic self-propelled particles that migrate upstream, known as positive rheotaxis. This phenomenon results from a purely physical mechanism involving the interplay between the polarity of the particles and their alignment by a viscous torque. We show quantitative agreement between experimental data and a simple model of an overdamped Brownian pendulum. The model notably predicts the existence of a stagnation point in a diverging flow. We take advantage of this property to demonstrate that our active particles can sense and predictably organize in an imposed flow. Our colloidal system represents an important step toward the realization of biomimetic microsystems with the ability to sense and respond to environmental changes.

  20. Integration of C4-specific ppdk gene of Echinochloa to C3 upland ...

    African Journals Online (AJOL)

    Pyruvate orthophosphate dikinase (PPDK) plays a key role in C4 photosynthetic pathway. The enzymatic reaction is one of the rate-limiting steps of the C4 photosynthetic pathway. In this paper, the gene encoding Echinochloa pyruvate orthosphate dikinase (GenBank accession number: AB289641) was introduced into H65 ...

  1. Germination shifts of C3 and C4 species under simulated global warming scenario.

    Science.gov (United States)

    Zhang, Hongxiang; Yu, Qiang; Huang, Yingxin; Zheng, Wei; Tian, Yu; Song, Yantao; Li, Guangdi; Zhou, Daowei

    2014-01-01

    Research efforts around the world have been increasingly devoted to investigating changes in C3 and C4 species' abundance or distribution with global warming, as they provide important insight into carbon fluxes and linked biogeochemical cycles. However, changes in the early life stage (e.g. germination) of C3 and C4 species in response to global warming, particularly with respect to asymmetric warming, have received less attention. We investigated germination percentage and rate of C3 and C4 species under asymmetric (+3/+6°C at day/night) and symmetric warming (+5/+5°C at day/night), simulated by alternating temperatures. A thermal time model was used to calculate germination base temperature and thermal time constant. Two additional alternating temperature regimes were used to test temperature metrics effect. The germination percentage and rate increased continuously for C4 species, but increased and then decreased with temperature for C3 species under both symmetric and asymmetric warming. Compared to asymmetric warming, symmetric warming significantly overestimated the speed of germination percentage change with temperature for C4 species. Among the temperature metrics (minimum, maximum, diurnal temperature range and average temperature), maximum temperature was most correlated with germination of C4 species. Our results indicate that global warming may favour germination of C4 species, at least for the C4 species studied in this work. The divergent effects of asymmetric and symmetric warming on plant germination also deserve more attention in future studies.

  2. 26 CFR 1.381(c)(4)-1 - Method of accounting.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Method of accounting. 1.381(c)(4)-1 Section 1... TAX (CONTINUED) INCOME TAXES Insolvency Reorganizations § 1.381(c)(4)-1 Method of accounting. (a... section 381(a) applies, an acquiring corporation shall use the same method of accounting used by the...

  3. Phosphoenolpyruvate carboxylase from C4 leaves is selectively targeted for inhibition by anionic phospholipids

    NARCIS (Netherlands)

    Monreal, J.A.; McLoughlin, F.; Echevarría, C.; García-Mauriño, S.; Testerink, C.

    2010-01-01

    Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) is an enzyme playing a crucial role in photosynthesis of C4 plants. Here, we identify anionic phospholipids as novel regulators that inhibit C4 PEPC activity and provide evidence that the enzyme partially localizes to membranes.

  4. Engineering C4 photosynthesis into C3 chassis in the synthetic biology age.

    Science.gov (United States)

    Schuler, Mara L; Mantegazza, Otho; Weber, Andreas P M

    2016-07-01

    C4 photosynthetic plants outperform C3 plants in hot and arid climates. By concentrating carbon dioxide around Rubisco C4 plants drastically reduce photorespiration. The frequency with which plants evolved C4 photosynthesis independently challenges researchers to unravel the genetic mechanisms underlying this convergent evolutionary switch. The conversion of C3 crops, such as rice, towards C4 photosynthesis is a long-standing goal. Nevertheless, at the present time, in the age of synthetic biology, this still remains a monumental task, partially because the C4 carbon-concentrating biochemical cycle spans two cell types and thus requires specialized anatomy. Here we review the advances in understanding the molecular basis and the evolution of the C4 trait, advances in the last decades that were driven by systems biology methods. In this review we emphasise essential genetic engineering tools needed to translate our theoretical knowledge into engineering approaches. With our current molecular understanding of the biochemical C4 pathway, we propose a simplified rational engineering model exclusively built with known C4 metabolic components. Moreover, we discuss an alternative approach to the progressing international engineering attempts that would combine targeted mutagenesis and directed evolution. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  5. Cinnamate 4-Hydroxylase (C4H) genes from Leucaena leucocephala: a pulp yielding leguminous tree.

    Science.gov (United States)

    Kumar, Santosh; Omer, Sumita; Patel, Krunal; Khan, Bashir M

    2013-02-01

    Leucaena leucocephala is a leguminous tree species accounting for one-fourth of raw material supplied to paper and pulp industry in India. Cinnamate 4-Hydroxylase (C4H, EC 1.14.13.11) is the second gene of phenylpropanoid pathway and a member of cytochrome P450 family. There is currently intense interest to alter or modify lignin content of L. leucocephala. Three highly similar C4H alleles of LlC4H1 gene were isolated and characterized. The alleles shared more than 98 % sequence identity at amino acid level to each other. Binding of partial promoter of another C4H gene LlC4H2, to varying amounts of crude nuclear proteins isolated from leaf and stem tissues of L. leucocephala formed two loose and one strong complex, respectively, suggesting that the abundance of proteins that bind with the partial C4H promoter is higher in stem tissue than in leaf tissue. Quantitative Real Time PCR study suggested that among tissues of same age, root tissues had highest level of C4H transcripts. Maximum transcript level was observed in 30 day old root tissue. Among the tissues investigated, C4H activity was highest in 60 day old root tissues. Tissue specific quantitative comparison of lignin from developing seedling stage to 1 year old tree stage indicated that Klason lignin increased in tissues with age.

  6. The role of photorespiration during the evolution of C4 photosynthesis in the genus Flaveria

    Science.gov (United States)

    Mallmann, Julia; Heckmann, David; Bräutigam, Andrea; Lercher, Martin J; Weber, Andreas PM; Westhoff, Peter; Gowik, Udo

    2014-01-01

    C4 photosynthesis represents a most remarkable case of convergent evolution of a complex trait, which includes the reprogramming of the expression patterns of thousands of genes. Anatomical, physiological, and phylogenetic and analyses as well as computational modeling indicate that the establishment of a photorespiratory carbon pump (termed C2 photosynthesis) is a prerequisite for the evolution of C4. However, a mechanistic model explaining the tight connection between the evolution of C4 and C2 photosynthesis is currently lacking. Here we address this question through comparative transcriptomic and biochemical analyses of closely related C3, C3–C4, and C4 species, combined with Flux Balance Analysis constrained through a mechanistic model of carbon fixation. We show that C2 photosynthesis creates a misbalance in nitrogen metabolism between bundle sheath and mesophyll cells. Rebalancing nitrogen metabolism requires anaplerotic reactions that resemble at least parts of a basic C4 cycle. Our findings thus show how C2 photosynthesis represents a pre-adaptation for the C4 system, where the evolution of the C2 system establishes important C4 components as a side effect. DOI: http://dx.doi.org/10.7554/eLife.02478.001 PMID:24935935

  7. Germination Shifts of C3 and C4 Species under Simulated Global Warming Scenario

    Science.gov (United States)

    Zhang, Hongxiang; Yu, Qiang; Huang, Yingxin; Zheng, Wei; Tian, Yu; Song, Yantao; Li, Guangdi; Zhou, Daowei

    2014-01-01

    Research efforts around the world have been increasingly devoted to investigating changes in C3 and C4 species' abundance or distribution with global warming, as they provide important insight into carbon fluxes and linked biogeochemical cycles. However, changes in the early life stage (e.g. germination) of C3 and C4 species in response to global warming, particularly with respect to asymmetric warming, have received less attention. We investigated germination percentage and rate of C3 and C4 species under asymmetric (+3/+6°C at day/night) and symmetric warming (+5/+5°C at day/night), simulated by alternating temperatures. A thermal time model was used to calculate germination base temperature and thermal time constant. Two additional alternating temperature regimes were used to test temperature metrics effect. The germination percentage and rate increased continuously for C4 species, but increased and then decreased with temperature for C3 species under both symmetric and asymmetric warming. Compared to asymmetric warming, symmetric warming significantly overestimated the speed of germination percentage change with temperature for C4 species. Among the temperature metrics (minimum, maximum, diurnal temperature range and average temperature), maximum temperature was most correlated with germination of C4 species. Our results indicate that global warming may favour germination of C4 species, at least for the C4 species studied in this work. The divergent effects of asymmetric and symmetric warming on plant germination also deserve more attention in future studies. PMID:25137138

  8. Germination shifts of C3 and C4 species under simulated global warming scenario.

    Directory of Open Access Journals (Sweden)

    Hongxiang Zhang

    Full Text Available Research efforts around the world have been increasingly devoted to investigating changes in C3 and C4 species' abundance or distribution with global warming, as they provide important insight into carbon fluxes and linked biogeochemical cycles. However, changes in the early life stage (e.g. germination of C3 and C4 species in response to global warming, particularly with respect to asymmetric warming, have received less attention. We investigated germination percentage and rate of C3 and C4 species under asymmetric (+3/+6°C at day/night and symmetric warming (+5/+5°C at day/night, simulated by alternating temperatures. A thermal time model was used to calculate germination base temperature and thermal time constant. Two additional alternating temperature regimes were used to test temperature metrics effect. The germination percentage and rate increased continuously for C4 species, but increased and then decreased with temperature for C3 species under both symmetric and asymmetric warming. Compared to asymmetric warming, symmetric warming significantly overestimated the speed of germination percentage change with temperature for C4 species. Among the temperature metrics (minimum, maximum, diurnal temperature range and average temperature, maximum temperature was most correlated with germination of C4 species. Our results indicate that global warming may favour germination of C4 species, at least for the C4 species studied in this work. The divergent effects of asymmetric and symmetric warming on plant germination also deserve more attention in future studies.

  9. Increased complement C4d deposition at the maternal-fetal interface in unexplained recurrent miscarriage

    NARCIS (Netherlands)

    Meuleman, Tess; Cohen, Danielle; Swings, Godelieve M J S; Veraar, Kimberly; Claas, Frans H J; Bloemenkamp, Kitty W M

    2015-01-01

    C4d is a footprint of antibody-mediated classical complement activation, and has evolved as a useful diagnostic marker of antibody-mediated rejection. It is unknown if complement activation, as reflected by C4d deposition plays a role in unexplained recurrent miscarriage. In a case-control study

  10. New introductions of enterovirus 71 subgenogroup C4 strains, France, 2012.

    Science.gov (United States)

    Schuffenecker, Isabelle; Henquell, Cécile; Mirand, Audrey; Coste-Burel, Marianne; Marque-Juillet, Stéphanie; Desbois, Delphine; Lagathu, Gisèle; Bornebusch, Laure; Bailly, Jean-Luc; Lina, Bruno

    2014-08-01

    In France during 2012, human enterovirus 71 (EV-A71) subgenogroup C4 strains were detected in 4 children hospitalized for neonatal fever or meningitis. Phylogenetic analysis showed novel and independent EV-A71 introductions, presumably from China, and suggested circulation of C4 strains throughout France. This observation emphasizes the need for monitoring EV-A71 infections in Europe.

  11. Inflatable artificial sphincter

    Science.gov (United States)

    ... procedures to treat urine leakage and incontinence include: Anterior vaginal wall repair Urethral bulking with artificial material ... urinary incontinence Images Inflatable artificial sphincter Anal sphincter anatomy Inflatable artificial sphincter - series References Adams MC, Joseph ...

  12. Analysis of data mining classification by comparison of C4.5 and ID algorithms

    Science.gov (United States)

    Sudrajat, R.; Irianingsih, I.; Krisnawan, D.

    2017-01-01

    The rapid development of information technology, triggered by the intensive use of information technology. For example, data mining widely used in investment. Many techniques that can be used assisting in investment, the method that used for classification is decision tree. Decision tree has a variety of algorithms, such as C4.5 and ID3. Both algorithms can generate different models for similar data sets and different accuracy. C4.5 and ID3 algorithms with discrete data provide accuracy are 87.16% and 99.83% and C4.5 algorithm with numerical data is 89.69%. C4.5 and ID3 algorithms with discrete data provides 520 and 598 customers and C4.5 algorithm with numerical data is 546 customers. From the analysis of the both algorithm it can classified quite well because error rate less than 15%.

  13. Light harvesting and chloroplast electron transport in NADP-malic enzyme type C4 plants.

    Science.gov (United States)

    Nakajima Munekage, Yuri

    2016-06-01

    The structure of thylakoids in chloroplasts and the organization of the electron transport chain changed dynamically during the evolution of C4 photosynthesis, especially in the nicotinamide adenine dinucleotide phosphate (NADP)-malic enzyme type C4 species. Stacked grana membranes are strongly reduced in the bundle sheath chloroplasts of these plants, where photosystem II activity is diminished and cyclic electron transport around photosystem I mainly occurs. This change optimizes the ATP/NADPH production ratio in bundle sheath chloroplasts to drive the metabolic cycle of C4 photosynthesis. This review summarizes the current model of light harvesting and electron transport in the NADP-malic enzyme type C4 plants and discusses how it changed during the evolution of C4 photosynthesis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Photosynthetic metabolism of malate and aspartate in Flaveria trinervia a C4 dicot

    International Nuclear Information System (INIS)

    Moore, B.A.

    1986-01-01

    C 4 species are known to vary in their apparent relative use of malate and aspartate to mediate carbon flux through the C 4 cycle. These studies investigate some of the adjustments in photosynthetic carbon metabolism that occur during a dark to light transition and during expansion of leaves of Flaveria trinervia, a C 4 dicot. Enzyme localization studies with isolated leaf mesophyll and bundle sheath protoplasts, indicated that both C 4 acids are formed in the mesophyll chloroplast, and that aspartate is metabolized to malate in the bundle sheath chloroplast prior to decaroxylation there. During photosynthetic induction, the partitioning of 14 CO 2 between malate and aspartate showed a single oscillation of increased aspartate labelling after 5 min of illumination. Turnover of [4-14C] (malate plus aspartate) was slow initially during illumination, prior to establishment of active pools of C 4 cycle metabolites

  15. Complement activation product C4d in oral and oropharyngeal squamous cell carcinoma.

    Science.gov (United States)

    Ajona, D; Pajares, M J; Chiara, M D; Rodrigo, J P; Jantus-Lewintre, E; Camps, C; Suarez, C; Bagán, J V; Montuenga, L M; Pio, R

    2015-10-01

    Complement C4d-containing fragments have been proposed as diagnostic markers for lung cancer. The purpose of this study was to evaluate the presence of C4d in oropharyngeal (OPSCC) and oral (OSCC) squamous cell carcinomas. C4d staining was analyzed by immunohistochemistry in 244 OPSCC surgical specimens. C4d levels were quantified by ELISA in resting saliva samples from 48 patients with oral leukoplakia and 62 with OSCC. Plasma samples from 21 patients with leukoplakia and 30 with oral carcinoma were also studied. C4d staining in OPSCC specimens was associated with nodal invasion (P = 0.001), histopathologic grade (P = 0.014), disease stage (P = 0.040), and focal-adhesion kinase expression (P Saliva C4d levels were higher in patients with oral cancer than in subjects with leukoplakia (0.07 ± 0.07 vs 0.04 ± 0.03 μg ml(-1) , P = 0.003). The area under the ROC curve was 0.63 (95%CI: 0.55-0.71). Salivary C4d levels in stage IV patients were higher than in patients with earlier stages (P = 0.028) and correlated with tumor size (P = 0.045). Plasma C4d levels also correlated with salivary C4d levels (P = 0.041), but differences between patients with oral cancer and subjects with leukoplakia were not significant (1.26 ± 0.59 vs 1.09 ± 0.39 μg ml(-1) , P = 0.232). C4d-containing fragments are detected in oral primary tumors and are increased in saliva from patients with OSCC. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Effects of timed artificial insemination following estrus ...

    African Journals Online (AJOL)

    The objectives of this study were to evaluate estrus response and pregnancy rates resulting from timed artificial insemination (AI) following estrus synchronization using CIDR in postpartum beef cattle. A total of 100 cows were randomly divided into three groups. Groups 1, 2 and 3 were artificially inseminated at 48-50 h ...

  17. Atomic-scale microstructures of Zr2Al3C4 and Zr3Al3C5 ceramics

    International Nuclear Information System (INIS)

    Lin, Z.J.; Zhuo, M.J.; He, L.F.; Zhou, Y.C.; Li, M.S.; Wang, J.Y.

    2006-01-01

    The microstructures of bulk Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 ceramics have been investigated using transmission electron microscopy and scanning transmission electron microscopy. These two carbides were determined to have a point group 6/mmm and a space group P6 3 /mmc using selected-area electron diffraction and convergent beam electron diffraction. The atomic-scale microstructures of Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 were investigated through high-resolution imaging and Z-contrast imaging. Furthermore, intergrowth between Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 was identified. Stacking faults in Zr 3 Al 3 C 5 were found to result from the insertion of an additional Zr-C layer. Cubic ZrC was occasionally identified to be incorporated in elongated Zr 3 Al 3 C 5 grains. In addition, Al may induce a twinned ZrC structure and lead to the formation of ternary zirconium aluminum carbides

  18. Targeted Knockdown of GDCH in Rice Leads to a Photorespiratory-Deficient Phenotype Useful as a Building Block for C4 Rice.

    Science.gov (United States)

    Lin, HsiangChun; Karki, Shanta; Coe, Robert A; Bagha, Shaheen; Khoshravesh, Roxana; Balahadia, C Paolo; Ver Sagun, Julius; Tapia, Ronald; Israel, W Krystler; Montecillo, Florencia; de Luna, Albert; Danila, Florence R; Lazaro, Andrea; Realubit, Czarina M; Acoba, Michelle G; Sage, Tammy L; von Caemmerer, Susanne; Furbank, Robert T; Cousins, Asaph B; Hibberd, Julian M; Quick, W Paul; Covshoff, Sarah

    2016-05-01

    The glycine decarboxylase complex (GDC) plays a critical role in the photorespiratory C2 cycle of C3 species by recovering carbon following the oxygenation reaction of ribulose-1,5-bisphosphate carboxylase/oxygenase. Loss of GDC from mesophyll cells (MCs) is considered a key early step in the evolution of C4 photosynthesis. To assess the impact of preferentially reducing GDC in rice MCs, we decreased the abundance of OsGDCH (Os10g37180) using an artificial microRNA (amiRNA) driven by a promoter that preferentially drives expression in MCs. GDC H- and P-proteins were undetectable in leaves of gdch lines. Plants exhibited a photorespiratory-deficient phenotype with stunted growth, accelerated leaf senescence, reduced chlorophyll, soluble protein and sugars, and increased glycine accumulation in leaves. Gas exchange measurements indicated an impaired ability to regenerate ribulose 1,5-bisphosphate in photorespiratory conditions. In addition, MCs of gdch lines exhibited a significant reduction in chloroplast area and coverage of the cell wall when grown in air, traits that occur during the later stages of C4 evolution. The presence of these two traits important for C4 photosynthesis and the non-lethal, down-regulation of the photorespiratory C2 cycle positively contribute to efforts to produce a C4 rice prototype. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. 348 Pain Control by Coaptation Procedure C3 and C4 Anterior Rami to Brachial Plexus.

    Science.gov (United States)

    Yamada, Shokei; Lonser, Russell R; Won, Daniel J; Tsao, Bryan E

    2016-08-01

    Previously, the authors presented the coaptation of C3 and C4 primary rami to one of brachial plexus trunks to regain function from cervical root avulsion-caused paralysis. The purpose of this presentation is 2-fold: (1) discuss specific surgical techniques and (2) discuss control or prevention of intractable pain associated with root avulsion. (1) The surgical procedure consists of exposure of C3 and C4 anterior rami coaptation to the upper trunk (Erb-Duchenne) or lower trunk (Klumpke), with sural nerve bridge graft, and additionally intercostal nerve coaptation to median and ulnar nerves for flail arm. (2) Of 30 total patients, 23 patients presented with Erb-Duchenne palsy due to C5 and C6 root avulsion, 3 presented with Klumpke palsy due to C8 and T1 avulsion, and 4 presented with C5 through T1 avulsion (a flail arm). These patients are divided into 2 groups according to pain control: Group 1 patients were operated on within 3 months after avulsion, group 2 was treated surgically later than 3 months postinjury. (1) The surgical procedure consists of exposure of C3 and C4 anterior rami coaptation to the upper trunk (Erb-Duchenne) or lower trunk (Klumpke), with sural nerve bridge graft, and additionally intercostal nerve coaptation to median and ulnar nerves for flail arm. (2) Of 30 patients, 23 patients presented with Erb-Duchenne palsy due to C5 and C6 root avulsion, 3 presented with Klumpke palsy due to C8 and T1 avulsion, and 4 presented with C5 through T1 avulsion (a flail arm). These patients are divided into 2 groups according to pain control: Group 1 patients were operated on within 3 months after avulsion; group 2 was treated surgically later than 3 months post injury. Coaptation procedures are effective to control arm and hand pain associated with nerve root avulsion.

  20. High-biomass C4 grasses-Filling the yield gap.

    Science.gov (United States)

    Mullet, John E

    2017-08-01

    A significant increase in agricultural productivity will be required by 2050 to meet the needs of an expanding and rapidly developing world population, without allocating more land and water resources to agriculture, and despite slowing rates of grain yield improvement. This review examines the proposition that high-biomass C 4 grasses could help fill the yield gap. High-biomass C 4 grasses exhibit high yield due to C 4 photosynthesis, long growth duration, and efficient capture and utilization of light, water, and nutrients. These C 4 grasses exhibit high levels of drought tolerance during their long vegetative growth phase ideal for crops grown in water-limited regions of agricultural production. The stems of some high-biomass C 4 grasses can accumulate high levels of non-structural carbohydrates that could be engineered to enhance biomass yield and utility as feedstocks for animals and biofuels production. The regulatory pathway that delays flowering of high-biomass C 4 grasses in long days has been elucidated enabling production and deployment of hybrids. Crop and landscape-scale modeling predict that utilization of high-biomass C 4 grass crops on land and in regions where water resources limit grain crop yield could increase agricultural productivity. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Chalcone-based Selective Inhibitors of a C4 Plant Key Enzyme as Novel Potential Herbicides

    Science.gov (United States)

    Nguyen, G. T. T.; Erlenkamp, G.; Jäck, O.; Küberl, A.; Bott, M.; Fiorani, F.; Gohlke, H.; Groth, G.

    2016-06-01

    Weeds are a challenge for global food production due to their rapidly evolving resistance against herbicides. We have identified chalcones as selective inhibitors of phosphoenolpyruvate carboxylase (PEPC), a key enzyme for carbon fixation and biomass increase in the C4 photosynthetic pathway of many of the world’s most damaging weeds. In contrast, many of the most important crop plants use C3 photosynthesis. Here, we show that 2‧,3‧,4‧,3,4-Pentahydroxychalcone (IC50 = 600 nM) and 2‧,3‧,4‧-Trihydroxychalcone (IC50 = 4.2 μM) are potent inhibitors of C4 PEPC but do not affect C3 PEPC at a same concentration range (selectivity factor: 15-45). Binding and modeling studies indicate that the active compounds bind at the same site as malate/aspartate, the natural feedback inhibitors of the C4 pathway. At the whole plant level, both substances showed pronounced growth-inhibitory effects on the C4 weed Amaranthus retroflexus, while there were no measurable effects on oilseed rape, a C3 plant. Growth of selected soil bacteria was not affected by these substances. Our chalcone compounds are the most potent and selective C4 PEPC inhibitors known to date. They offer a novel approach to combat C4 weeds based on a hitherto unexplored mode of allosteric inhibition of a C4 plant key enzyme.

  2. Interrelations between C4 Ketogenesis, C5 Ketogenesis, and Anaplerosis in the Perfused Rat Liver*

    OpenAIRE

    Deng, Shuang; Zhang, Guo-Fang; Kasumov, Takhar; Roe, Charles R.; Brunengraber, Henri

    2009-01-01

    We investigated the interrelations between C4 ketogenesis (production of β-hydroxybutyrate + acetoacetate), C5 ketogenesis (production of β-hydroxypentanoate + β-ketopentanoate), and anaplerosis in isolated rat livers perfused with 13C-labeled octanoate, heptanoate, or propionate. Mass isotopomer analysis of C4 and C5 ketone bodies and of related acyl-CoA esters reveal that C4 and C5 ketogenesis share the same pool of acetyl-CoA. Although the uptake of octanoate and heptanoate by the liver ar...

  3. Renal AA amyloidosis in a patient with hereditary complete complement C4 deficiency

    Directory of Open Access Journals (Sweden)

    Imed Helal

    2011-01-01

    Full Text Available Hereditary complete C4 deficiency has until now been reported in 30 cases only. A disturbed clearance of immune- complexes probably predisposes these individuals to systemic lupus erythematosus, other immune- complex diseases and recurrent microbial infections. We present here a 20- year- old female with hereditary complete C4 deficiency. Renal biopsy demonstrated renal AA amyloidosis. This unique case further substantiates that deficiency of classical pathway components predisposes to the development of recurrent microbial infections and that the patients may develop AA amyloidosis. Furthermore, in clinical practice, the nephrotic syndrome occurring in a patient with hereditary complete complement C4 deficiency should lead to the suspicion of renal AA amyloidosis.

  4. Klasifikasi Nilai Kelayakan Calon Debitur Baru Menggunakan Decision Tree C4.5

    Directory of Open Access Journals (Sweden)

    Bambang Hermanto

    2017-01-01

    Full Text Available In an effort to improve the quality of customer service, especially in terms of feasibility assessment of borrowers due to the increasing number of new prospective borrowers loans financing the purchase of a motor vehicle, then the company needs a decision making tool allowing you to easily and quickly estimate Where the debtor is able to pay off the loans. This study discusses the process generates C4.5 decision tree algorithm and utilizing the learning group of debtor financing dataset motorcycle. The decision tree is then interpreted into the form of decision rules that can be understood and used as a reference in processing the data of borrowers in determining the feasibility of prospective new borrowers. Feasibility value refers to the value of the destination parameter credit status. If the value of the credit is paid off status mean estimated prospective borrower is able to repay the loan in question, but if the credit status parameters estimated worth pull means candidates concerned debtor is unable to pay loans.. System testing is done by comparing the results of the testing data by learning data in three scenarios with the decision that the data is valid at over 70% for all case scenarios. Moreover, in generated tree  and generate rules takes fairly quickly, which is no more than 15 minutes for each test scenario

  5. Proposed model for disorder in the warmest crystalline phase of C4F8

    International Nuclear Information System (INIS)

    Bartell, L.S.; Powell, B.M.

    1989-01-01

    A representation of the molecular disorder in the plastically crystalline phase of perfluorocyclobutane existing between 216 K and 233 K is formulated to account for the intensities of the four X-ray and four neutron powder diffraction lines observed in recent experiments. A previous interpretation of the X-ray pattern in terms of a body-centred cubic lattice with two molecules per cell is retained and possible models distributing puckered, cyclic molecules among partially occupied cubic sites are examined. Among such models only one, orienting the carbon ring diagonals parallel to the cell axes, space group Im3m, with six molecular orientations per site, satisfied both the X-ray and neutron intensities. The proposed model has all nonbonded contacts at or exceeding the normal van der Waals distances. Debye-Waller factors and diffuse scattering indicate large molecular motions, compatible with the known facile self-diffusion reported in an N.M.R. study. The model suggests that flexible C 4 F 8 molecules are puckered by the same amount in the solid and gas phases. (author)

  6. A pyogenic discitis at c3-c4 with associated ventral epidural abscess involving c1-c4 after intradiscal oxygen-ozone chemonucleolysis: a case report.

    Science.gov (United States)

    Bo, Wu; Longyi, Chen; Jian, Tang; Guangfu, Huang; Hailong, Feng; Weidong, Liu; Haibin, Tan

    2009-04-15

    A case report and clinical discussion. To describe an unique case of purulent discitis at C3-C4 and an anterior C1-C4 epidural abscess secondary to oxygen-ozone therapy for the herniated cervical discs. Previously reported complications secondary to ozone therapy are rarely documented. No cases of pyogenic discitis with associated epidural abscess after oxygen-ozone therapy have been reported to date. To our knowledge, this is the first such case reported in literature. A 57-year-old female patient with nuchal stiffness was previously treated with ozone therapy at the discs of C3-C4, C4-C5, and C6-C7. Five days later, she presented with an attack of neck pain and fever followed by progressive quadriplegia with sudden onset of dyspnea and was referred to our hospital. On admission, physical examination revealed a temperature of 38.8 degrees C, evident neck tenderness, marked global weakness (grade 1-2/5 MRC) in bilateral upper-limb, and a modest global weakness in bilateral lower-limb (grade 4/5 MRC). Laboratory findings showed a significantly elevated WCC, ESR, and CRP. Blood culture was negative. Enhanced-MR imaging demonstrated a purulent discitis at C3-C4 and a ventral C1-C4 epidural abscess with homogenous enhancement indicative of a solid phlegmonous granulation tissue. We formulated a 3-stage treatment involving C1-C4 multilevel decompressive laminectomies, subtotal unilateral C3-C4 facetectomies, and tissue sampling for culture with application of a corset after surgery, followed by a delayed secondary posterior thorough drainage of epidural liquid pus using a suction-irrigation drainage, after the abscess had turned to a necrotic liquid abscess, on the basis of findings of enhanced-MR imaging, by 10-day duration of intravenously antibiotic therapy tailored to Streptococcus bovis isolated from infected tissue. Over the next few weeks, the patient made an excellent neurologic recovery. However, she did not consent to undergo further occipitocervical fusion

  7. Rapid C4I High Performance Computing for Hyperspectral Imaging Exploitation

    National Research Council Canada - National Science Library

    Ramseyer, George O; Spetka, Scott E; Linderman, Richard E; Romano, Brian C

    2001-01-01

    A multidisciplinary effort has been initiated which spans the C4I and signal/image processing computational technology areas to integrate diverse capabilities of existing hyperspectral image exploitation systems...

  8. Electron attachment properties of c-C4F8O\

    Czech Academy of Sciences Publication Activity Database

    Chachereau, A.; Fedor, Juraj; Janečková, R.; Kočišek, Jaroslav; Rabie, M.; Franck, C. M.

    2016-01-01

    Roč. 49, č. 37 (2016), 375201 ISSN 0022-3727 Institutional support: RVO:61388955 Keywords : C4F8O * octafluorotetrahydrofuran * attachment cross section Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.588, year: 2016

  9. Deployment of 802.15.4 Sensor Networks for C4ISR Operations

    National Research Council Canada - National Science Library

    Ngo, Damian N

    2006-01-01

    .... The objective of this thesis is to focus on the deployment issues of WSNs. In addition, this thesis assesses the optimal configurations and environment that enables the sensor networks to thrive in a C4ISR environment...

  10. Re-Use of Integrated Dictionary Components for C4ISR Architectures

    National Research Council Canada - National Science Library

    Ali, Asma T

    2003-01-01

    The C4ISR Architecture Framework Products can be developed using mapping between Structured Analysis products and the Framework products and also based on mapping between Object Orientation and Framework products...

  11. Systems Engineering Air, Land, Sea, Space & C4ISR Experiential Applications [video

    OpenAIRE

    Finley, James I.

    2012-01-01

    Meyer Institute Guest Speaker Presentation May 24, 2012, The Honorable James I. Finley Deputy Undersecretary of Defense Acquisition & Technology, Systems Engineering Air, Land, Sea, Space & C4ISR Experiential Applications.

  12. Kranz leaf anatomy and C4 dicarboxylic acid pathway of photosynthesis in Spinifex squarrosus L

    International Nuclear Information System (INIS)

    Rama Das, V.S.; Raghavendra, A.S.

    1977-01-01

    S. squarrosus, a panicoid grass found on semi-arid sandy sea shores, had the typical 'Kranz' leaf anatomy and the C 4 dicarboxylic acid pathway of photosynthesis. Bundle sheath chloroplasts were equally distributed around the cell walls. Leaves fixed as much as 63 mg CO 2 /dm 2 /hr and possessed a low carbon dioxide compensation point. During short term exposure to 14 CO 2 , leaves fixed most of the radioactivity into the C 4 acids, malate and aspartate. Predominant malate formation, high activities of NADP malate dehydrogenase and NADP malic enzyme suggested that S. squarrosus is a NADP malic enzyme type C 4 plant. C 4 dicarboxylic acid pathway of photosynthesis in Spinifex is advantageous in relation to its habitat of high light intensity and high temperatures in saline sandy regions. (author)

  13. C3 and C4 biomass allocation responses to elevated CO2 and nitrogen: contrasting resource capture strategies

    Science.gov (United States)

    White, K.P.; Langley, J.A.; Cahoon, D.R.; Megonigal, J.P.

    2012-01-01

    Plants alter biomass allocation to optimize resource capture. Plant strategy for resource capture may have important implications in intertidal marshes, where soil nitrogen (N) levels and atmospheric carbon dioxide (CO2) are changing. We conducted a factorial manipulation of atmospheric CO2 (ambient and ambient + 340 ppm) and soil N (ambient and ambient + 25 g m-2 year-1) in an intertidal marsh composed of common North Atlantic C3 and C4 species. Estimation of C3 stem turnover was used to adjust aboveground C3 productivity, and fine root productivity was partitioned into C3-C4 functional groups by isotopic analysis. The results suggest that the plants follow resource capture theory. The C3 species increased aboveground productivity under the added N and elevated CO2 treatment (P 2 alone. C3 fine root production decreased with added N (P 2 (P = 0.0481). The C4 species increased growth under high N availability both above- and belowground, but that stimulation was diminished under elevated CO2. The results suggest that the marsh vegetation allocates biomass according to resource capture at the individual plant level rather than for optimal ecosystem viability in regards to biomass influence over the processes that maintain soil surface elevation in equilibrium with sea level.

  14. PhC-4 new high-speed camera with mirror scanning

    International Nuclear Information System (INIS)

    Daragan, A.O.; Belov, B.G.

    1979-01-01

    The description of the optical system and the construction of the high-speed PhC-4 photographic camera with mirror scanning of the continuously operating type is given. The optical system of the camera is based on the foursided rotating mirror, two optical inlets and two working sectors. The PhC-4 camera provides the framing rate up to 600 thousand frames per second. (author)

  15. Use of C4d as a diagnostic tool to classify membranoproliferative glomerulonephritis.

    Science.gov (United States)

    Gupta, Nirupama; Wakefield, Dara N; Clapp, William L; Garin, Eduardo H

    Membranoproliferative glomerulonephritis (MPGN type I, II and III) was reclassified in 2013 as MPGN and C3 glomerulopathy (C3G) based on the complement system activation mechanism. To evaluate whether C4d, a component of the classical pathway, could be a diagnostic tool in differentiating between MPGN and C3G. We conducted a retrospective study of 15 MPGN type I, II and III and 13 minimal change disease (MCD) patients diagnosed between 2000 and 2012. C4d staining using the peroxidase method was employed. Using the 2013 C3G consensus classification, the 15 MPGN types I, II and III biopsies were re-classified as MPGN (8) and C3G (7). Following C4d staining, of the 8 biopsies diagnosed as MPGN, 4 had classical pathway involvement [C1q (+), C3 (+), C4d (+)]; two had lectin pathway involvement [C1q (-), C3 (+), C4d (+)]; and, two were reclassified as C3G because the absence of C4d and C1q suggested the presence of the alternative pathway [C1q (-), C3 (+), C4d (-)]. Three of the seven C3G biopsies presented classical pathway involvement and were reclassified as MPGN. The alternative pathway was present in one of the other 4 biopsies considered to be C3G. Two C3G biopsies involved the lectin pathway and the one case of dense deposit disease had lectin pathway involvement. C4d staining may help to differentiate between MPGN and C3G. In addition, the lectin pathway could play a role in the pathogenesis of these glomerulopathies. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  16. Acute humoral rejection and C4d immunostaining in ABO blood type-incompatible liver transplantation.

    Science.gov (United States)

    Haga, Hironori; Egawa, Hiroto; Fujimoto, Yasuhiro; Ueda, Mikiko; Miyagawa-Hayashino, Aya; Sakurai, Takaki; Okuno, Tomoko; Koyanagi, Itsuko; Takada, Yasutsugu; Manabe, Toshiaki

    2006-03-01

    Complement C4d deposition in graft capillaries has been reported to be associated with antibody-mediated rejection in kidney and other solid organ transplantation. The correlation of C4d deposits and humoral rejection in liver transplants, however, is not well understood. We investigated the C4d immunostaining pattern in 34 patients whose liver biopsy was taken within the first 3 postoperative weeks for suspected acute rejection after ABO blood type-incompatible liver transplantation. The staining pattern was classified as positive (portal stromal staining), indeterminate (endothelial staining only), and negative (no staining). Positive C4d immunostaining was seen in 17 (50%) patients and was significantly associated with high (x64 or more) postoperative antidonor A/B antibody (immunoglobulin M (IgM)) titers (88 vs. 35%, P = 0.002) and poorer overall survival rate (41 vs. 88%, P = 0.007). Ten of 11 (91%) cases with histological acute humoral rejection (periportal edema and necrosis (PEN) or portal hemorrhagic edema) were positive for C4d, all of which showed high postoperative antibody titers. The other histologies associated with C4d positivity was purulent cholangitis (n = 4), coagulative hepatocyte necrosis (n = 1), acute cellular rejection (n = 1), and hepatocanalicular cholestasis (n = 1). Full clinical recovery was observed in only 6 of 17 (35%) C4d-positive patients, and tended to be associated with a lower rejection activity index (RAI). In conclusion, our study indicates that C4d deposits in the portal stroma can be a hallmark of acute humoral rejection in ABO-incompatible liver transplantation, and allograft damage can be reversible in a minority of cases. Copyright 2006 AASLD

  17. NDH-Mediated Cyclic Electron Flow Around Photosystem I is Crucial for C4 Photosynthesis.

    Science.gov (United States)

    Ishikawa, Noriko; Takabayashi, Atsushi; Noguchi, Ko; Tazoe, Youshi; Yamamoto, Hiroshi; von Caemmerer, Susanne; Sato, Fumihiko; Endo, Tsuyoshi

    2016-10-01

    C 4 photosynthesis exhibits efficient CO 2 assimilation in ambient air by concentrating CO 2 around ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) through a metabolic pathway called the C 4 cycle. It has been suggested that cyclic electron flow (CEF) around PSI mediated by chloroplast NADH dehydrogenase-like complex (NDH), an alternative pathway of photosynthetic electron transport (PET), plays a crucial role in C 4 photosynthesis, although the contribution of NDH-mediated CEF is small in C 3 photosynthesis. Here, we generated NDH-suppressed transformants of a C 4 plant, Flaveria bidentis, and showed that the NDH-suppressed plants grow poorly, especially under low-light conditions. CO 2 assimilation rates were consistently decreased in the NDH-suppressed plants under low and medium light intensities. Measurements of non-photochemical quenching (NPQ) of Chl fluorescence, the oxidation state of the reaction center of PSI (P700) and the electrochromic shift (ECS) of pigment absorbance indicated that proton translocation across the thylakoid membrane is impaired in the NDH-suppressed plants. Since proton translocation across the thylakoid membrane induces ATP production, these results suggest that NDH-mediated CEF plays a role in the supply of ATP which is required for C 4 photosynthesis. Such a role is more crucial when the light that is available for photosynthesis is limited and the energy production by PET becomes rate-determining for C 4 photosynthesis. Our results demonstrate that the physiological contribution of NDH-mediated CEF is greater in C 4 photosynthesis than in C 3 photosynthesis, suggesting that the mechanism of PET in C 4 photosynthesis has changed from that in C 3 photosynthesis accompanying the changes in the mechanism of CO 2 assimilation. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Arterial Blood Pressure Induces Transient C4b-Binding Protein in Human Saphenous Vein Grafts.

    Science.gov (United States)

    Kupreishvili, Koba; Meischl, Christof; Vonk, Alexander B A; Stooker, Wim; Eijsman, Leon; Blom, Anna M; Quax, Paul H A; van Hinsbergh, Victor W M; Niessen, Hans W M; Krijnen, Paul A J

    2017-05-01

    Complement is an important mediator in arterial blood pressure-induced vein graft failure. Previously, we noted activation of cell protective mechanisms in human saphenous veins too. Here we have analyzed whether C4b-binding protein (C4bp), an endogenous complement inhibitor, is present in the vein wall. Human saphenous vein segments obtained from patients undergoing coronary artery bypass grafting (n = 55) were perfused in vitro at arterial blood pressure with either autologous blood for 1, 2, 4, or 6 hr or with autologous blood supplemented with reactive oxygen species scavenger N-acetylcysteine. The segments were subsequently analyzed quantitatively for presence of C4bp and complement activation product C3d using immunohistochemistry. Perfusion induced deposition of C3d and C4bp within the media of the vessel wall, which increased reproducibly and significantly over a period of 4 hr up to 3.8% for C3d and 81% for C4bp of the total vessel area. Remarkably after 6 hr of perfusion, the C3d-positive area decreased significantly to 1.3% and the C4bp-positive area to 19% of the total area of the vein. The areas positive for both C4bp and C3d were increased in the presence of N-acetylcysteine. Exposure to arterial blood pressure leads to a transient presence of C4bp in the vein wall. This may be part of a cell-protective mechanism to counteract arterial blood pressure-induced cellular stress and inflammation in grafted veins. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Klasifikasi Penerimaan Mahasiswa Baru Menggunakan Algortima C4.5 Dan Adaboost (Studi Kasus : STMIK XYZ

    Directory of Open Access Journals (Sweden)

    Yoga Handoko Agustin

    2017-02-01

    Full Text Available Every college student wants to get a good quality and the quantity corresponding to the quota in charge of the university. The quality of new students can be seen early by recognizing the pattern of student characteristics existing in previous years and noticed a long period of study.C4.5 algorithm is a model for building a decision tree, this algorithm is intended for supervised learning: value attribute in the dataset described by a collection of attributes and including one of a series of interconnected classes. To improve the accuracy in the process of classification and prediction by means generate a combination of a model, then used modeling boosting namely Adaboost. Experiments conducted on 546 datasets using C4.5 algorithms based adaboost to produce accuracy. From the experiments conducted to produce the same accuracy values between algorithm C4.5 and C4.5 algorithm based on Adaboost is equal to 77.33% Precision, Accuracy 90.28%, 45.54% Recall but there is a difference in AUC values for C4.5 Algorithm by 0683 while Adaboost algorithm C4.5 Driven by 0.717. The patterns can help to take the decision of new admissions to graduate on time and graduate students can be predictable late early.

  20. Rising atmospheric carbon dioxide concentration and the future of C4 crops for food and fuel.

    Science.gov (United States)

    Leakey, Andrew D B

    2009-07-07

    Crops with the C(4) photosynthetic pathway are vital to global food supply, particularly in the tropical regions where human well-being and agricultural productivity are most closely linked. While rising atmospheric [CO(2)] is the driving force behind the greater temperatures and water stress, which threaten to reduce future crop yields, it also has the potential to directly benefit crop physiology. The nature of C(4) plant responses to elevated [CO(2)] has been controversial. Recent evidence from free-air CO(2) enrichment (FACE) experiments suggests that elevated [CO(2)] does not directly stimulate C(4) photosynthesis. Nonetheless, drought stress can be ameliorated at elevated [CO(2)] as a result of lower stomatal conductance and greater intercellular [CO(2)]. Therefore, unlike C(3) crops for which there is a direct enhancement of photosynthesis by elevated [CO(2)], C(4) crops will only benefit from elevated [CO(2)] in times and places of drought stress. Current projections of future crop yields have assumed that rising [CO(2)] will directly enhance photosynthesis in all situations and, therefore, are likely to be overly optimistic. Additional experiments are needed to evaluate the extent to which amelioration of drought stress by elevated [CO(2)] will improve C(4) crop yields for food and fuel over the range of C(4) crop growing conditions and genotypes.

  1. C4 deficiency is a predisposing factor for Streptococcus pneumoniae-induced autoantibody production

    Science.gov (United States)

    Yammani, Rama D.; Leyva, Marcela A.; Jennings, Ryan N.; Haas, Karen M.

    2015-01-01

    Reductions in C4 levels may predispose individuals to infection with encapsulated bacteria as well as autoimmunity. In this study, we examined the role C4 has in protection against Streptococcus pneumoniae-induced autoimmunity. Mild respiratory infection with serotype 19F pneumococci selectively induced systemic anti-dsDNA IgA production in naïve C4-/- mice, but not C3-/- or wild type mice. Systemic challenge with virulent serotype 3 pneumococci also induced anti-dsDNA IgA production in immune C4-/- mice. Remarkably, pneumococcal polysaccharide (PPS) vaccination alone induced C4-/- mice to produce increased anti-dsDNA IgA levels that were maintained in some mice for months. These effects were most pronounced in female C4-/- mice. Importantly, immunization-induced increases in anti-dsDNA IgA levels were strongly associated with increased IgA deposition in kidneys. Cross-reactivity between pneumococcal antigens and dsDNA played a partial role in the induction of anti-dsDNA IgA, but a major role for PPS-associated TLR2 agonists was also revealed. Administration of the TLR2/4 antagonist, OxPAPC, at the time of PPS immunization completely blocked the production of anti-dsDNA IgA in C4-/- mice without suppressing PPS-specific Ab production. The TLR2 agonist, Pam3Csk4, similarly induced anti-dsDNA IgA production in C4-/- mice, which OxPAPC also prevented. LPS, a TLR4 agonist, had no effect. Pam3Csk4, but not LPS, also induced dsDNA-specific IgA production by C4-/- splenic IgA+ B cells in vitro, indicating TLR2 agonists can stimulate autoAb production via B cell-intrinsic mechanisms. Collectively, our results show an important role for C4 in suppressing autoAb production elicited by cross-reactive antigens and TLR2 agonists associated with S. pneumoniae. PMID:25339671

  2. From museums to genomics: old herbarium specimens shed light on a C3 to C4 transition.

    Science.gov (United States)

    Besnard, Guillaume; Christin, Pascal-Antoine; Malé, Pierre-Jean G; Lhuillier, Emeline; Lauzeral, Christine; Coissac, Eric; Vorontsova, Maria S

    2014-12-01

    Collections of specimens held by natural history museums are invaluable material for biodiversity inventory and evolutionary studies, with specimens accumulated over 300 years readily available for sampling. Unfortunately, most museum specimens yield low-quality DNA. Recent advances in sequencing technologies, so called next-generation sequencing, are revolutionizing phylogenetic investigations at a deep level. Here, the Illumina technology (HiSeq) was used on herbarium specimens of Sartidia (subfamily Aristidoideae, Poaceae), a small African-Malagasy grass lineage (six species) characteristic of wooded savannas, which is the C3 sister group of Stipagrostis, an important C4 genus from Africa and SW Asia. Complete chloroplast and nuclear ribosomal sequences were assembled for two Sartidia species, one of which (S. perrieri) is only known from a single specimen collected in Madagascar 100 years ago. Partial sequences of a few single-copy genes encoding phosphoenolpyruvate carboxylases (ppc) and malic enzymes (nadpme) were also assembled. Based on these data, the phylogenetic position of Malagasy Sartidia in the subfamily Aristidoideae was investigated and the biogeographical history of this genus was analysed with full species sampling. The evolutionary history of two genes for C4 photosynthesis (ppc-aL1b and nadpme-IV) in the group was also investigated. The gene encoding the C4 phosphoenolpyruvate caroxylase of Stipagrostis is absent from S. dewinteri suggesting that it is not essential in C3 members of the group, which might have favoured its recruitment into a new metabolic pathway. Altogether, the inclusion of historical museum specimens in phylogenomic analyses of biodiversity opens new avenues for evolutionary studies. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  3. Renal Transplant Patients Biopsied for Cause and Tested for C4d, DSA, and IgG Subclasses and C1q: Which Humoral Markers Improve Diagnosis and Outcomes?

    Science.gov (United States)

    Cicciarelli, James C.; Chang, Youngil; Koss, Michael; Hacke, Katrin; Kasahara, Noriyuki; Burns, Kevin M.; Min, David I.; Naraghi, Robert; Shah, Tariq

    2017-01-01

    The association between donor specific antibodies (DSA) and renal transplant rejection has been generally established, but there are cases when a DSA is present without rejection. We examined 73 renal transplant recipients biopsied for transplant dysfunction with DSA test results available: 23 patients diffusely positive for C4d (C4d+), 25 patients focally positive for C4d, and 25 patients negative for C4d (C4d−). We performed C1q and IgG subclass testing in our DSA+ and C4d+ patient group. Graft outcomes were determined for the C4d+ group. All 23 C4d+ patients had IgG DSA with an average of 12,500 MFI (cumulative DSA MFI). The C4d− patients had average DSA less than 500 MFI. Among the patients with C4d+ biopsies, 100% had IgG DSA, 70% had C1q+ DSA, and 83% had complement fixing IgG subclass antibodies. Interestingly, IgG4 was seen in 10 of the 23 recipients' sera, but always along with complement fixing IgG1, and we have previously seen excellent function in patients when IgG4 DSA exists alone. Cumulative DSA above 10,000 MFI were associated with C4d deposition and complement fixation. There was no significant correlation between graft loss and C1q positivity, and IgG subclass analysis seemed to be a better correlate for complement fixing antibodies in the C4d+ patient group. PMID:28182088

  4. Plasma C4d as marker for lupus nephritis in systemic lupus erythematosus.

    Science.gov (United States)

    Martin, Myriam; Smoląg, Karolina I; Björk, Albin; Gullstrand, Birgitta; Okrój, Marcin; Leffler, Jonatan; Jönsen, Andreas; Bengtsson, Anders A; Blom, Anna M

    2017-12-06

    In the present study, we sought to evaluate the complement activation product C4d as a marker for lupus nephritis in systemic lupus erythematosus (SLE). C4d levels were determined by enzyme-linked immunosorbent assay in plasma samples of patients with established SLE using a novel approach based on detection of a short linear cleavage neoepitope. Cross-sectional associations were studied in 98 patients with SLE with samples taken at lower or higher respective disease activity. Temporal associations were investigated in 69 patients with SLE who were followed longitudinally for up to 5 years. Plasma samples from 77 healthy donors were included as controls. C4d levels were negligible in healthy control subjects and significantly increased in patients with SLE in the cross-sectional study (p Lupus Erythematosus Disease Activity Index (p = 0.011) and predominantly with lupus nephritis (p = 0.003), exhibiting a sensitivity of 79% to identify patients with nephritis. High C4d levels together with the presence of anti-dsDNA autoantibodies preceded and thus predicted future lupus nephritis in the longitudinal study (OR 5.4, 95% CI 1.4-21.3). When we considered only patients with renal involvement (19 of 69) during the longitudinal study, we found that high C4d levels alone could forecast recurrence of future lupus nephritis (OR 3.3, 95% CI 1.2-9.6). C4d appears to be a valuable marker for use in monitoring of patients with SLE, particularly for lupus nephritis. Importantly, C4d levels can predict impending flares of lupus nephritis and may thus be useful for informing treatment.

  5. Post-transcriptional regulation of photosynthetic genes is a key driver of C4 leaf ontogeny.

    Science.gov (United States)

    Fankhauser, Nicklaus; Aubry, Sylvain

    2017-01-01

    C 4 photosynthesis allows highly efficient carbon fixation that originates from tightly regulated anatomical and biochemical modifications of leaf architecture. Recent studies showed that leaf transcriptome modifications during leaf ontogeny of closely related C 3 (Tarenaya hassleriana) and C 4 (Gynandropsis gynandra) species within the Cleomaceae family existed but they did not identify any dedicated transcriptional networks or factors specifically driving C 4 leaf ontogeny. RNAseq analysis provides a steady-state quantification of whole-cell mRNAs but does not allow any discrimination between transcriptional and post-transcriptional processes that may occur simultaneously during leaf ontogeny. Here we use exon-intron split analysis (EISA) to determine the extent to which transcriptional and post-transcriptional processes are involved in the regulation of gene expression between young and expanded leaves in both species. C 4 -specific changes in post-transcriptional regulation were observed for genes involved in the Calvin-Benson cycle and some photosystem components but not for C 4 core-cycle genes. Overall, this study provides an unbiased genome-wide insight into the post-transcriptional mechanisms that regulate gene expression through the control of mRNA levels and could be central to the onset of C 4 photosynthesis. This mechanism is cytosolic which implies cell-specific modifications of mRNA stability. Understanding this mechanism may be crucial when aiming to transform C 3 crops into C 4 crops. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  6. A Dynamic Hydro-Mechanical and Biochemical Model of Stomatal Conductance for C4Photosynthesis.

    Science.gov (United States)

    Bellasio, Chandra; Quirk, Joe; Buckley, Thomas N; Beerling, David J

    2017-09-01

    C 4 plants are major grain (maize [ Zea mays ] and sorghum [ Sorghum bicolor ]), sugar (sugarcane [ Saccharum officinarum ]), and biofuel ( Miscanthus spp.) producers and contribute ∼20% to global productivity. Plants lose water through stomatal pores in order to acquire CO 2 (assimilation [ A ]) and control their carbon-for-water balance by regulating stomatal conductance ( g S ). The ability to mechanistically predict g S and A in response to atmospheric CO 2 , water availability, and time is critical for simulating stomatal control of plant-atmospheric carbon and water exchange under current, past, or future environmental conditions. Yet, dynamic mechanistic models for g S are lacking, especially for C 4 photosynthesis. We developed and coupled a hydromechanical model of stomatal behavior with a biochemical model of C 4 photosynthesis, calibrated using gas-exchange measurements in maize, and extended the coupled model with time-explicit functions to predict dynamic responses. We demonstrated the wider applicability of the model with three additional C 4 grass species in which interspecific differences in stomatal behavior could be accounted for by fitting a single parameter. The model accurately predicted steady-state responses of g S to light, atmospheric CO 2 and oxygen, soil drying, and evaporative demand as well as dynamic responses to light intensity. Further analyses suggest that the effect of variable leaf hydraulic conductance is negligible. Based on the model, we derived a set of equations suitable for incorporation in land surface models. Our model illuminates the processes underpinning stomatal control in C 4 plants and suggests that the hydraulic benefits associated with fast stomatal responses of C 4 grasses may have supported the evolution of C 4 photosynthesis. © 2017 American Society of Plant Biologists. All Rights Reserved.

  7. C4: Exploring Multiple Solutions in Graphical Models by Cluster Sampling.

    Science.gov (United States)

    Porway, Jake; Zhu, Song-Chun

    2011-09-01

    This paper presents a novel Markov Chain Monte Carlo (MCMC) inference algorithm called C(4)--Clustering with Cooperative and Competitive Constraints--for computing multiple solutions from posterior probabilities defined on graphical models, including Markov random fields (MRF), conditional random fields (CRF), and hierarchical models. The graphs may have both positive and negative edges for cooperative and competitive constraints. C(4) is a probabilistic clustering algorithm in the spirit of Swendsen-Wang. By turning the positive edges on/off probabilistically, C(4) partitions the graph into a number of connected components (ccps) and each ccp is a coupled subsolution with nodes connected by positive edges. Then, by turning the negative edges on/off probabilistically, C(4) obtains composite ccps (called cccps) with competing ccps connected by negative edges. At each step, C(4) flips the labels of all nodes in a cccp so that nodes in each ccp keep the same label while different ccps are assigned different labels to observe both positive and negative constraints. Thus, the algorithm can jump between multiple competing solutions (or modes of the posterior probability) in a single or a few steps. It computes multiple distinct solutions to preserve the intrinsic ambiguities and avoids premature commitments to a single solution that may not be valid given later context. C(4) achieves a mixing rate faster than existing MCMC methods, such as various Gibbs samplers and Swendsen-Wang cuts. It is also more "dynamic" than common optimization methods such as ICM, LBP, and graph cuts. We demonstrate the C(4) algorithm in line drawing interpretation, scene labeling, and object recognition.

  8. Photosynthetic induction in a C4, Flaveria trinervia. I. Initial products of 14CO2 assimilation and levels of whole leaf C4 metabolites

    International Nuclear Information System (INIS)

    Moore, B.D.; Edwards, G.E.

    1986-01-01

    Labeling patterns from 14 CO 2 pulses to leaves and whole leaf metabolite contents were examined during photosynthetic induction in Flaveria trinervia, a C 4 dicot of the NADP-malic enzyme subgroup. During the first one to two minutes of illumination, malate was the primary initial product of 14 CO 2 assimilation (about 77% of total 14 C incorporated). After about 5 minutes of illumination, the proportion of initial label to aspartate increased from 16 to 66%, and then gradually declined during the following 7 to 10 minutes of illumination. Nutrition experiments showed that the increase in 14 CO 2 partitioning to aspartate was delayed about 2.5 minutes in plants grown with limiting N, and was highly dampened in plants previously treated 10 to 12 days with ammonia as the sole N source. Measurements of C 4 leaf metabolites revealed several transients in metabolite pools during the first few minutes of illumination, and subsequently, more gradual adjustments in pool sizes. These include a large initial decrease in malate (about 1.6 micromoles per milligram chlorophyll) and a small initial decrease in pyruvate. There was a transient increase in alanine levels after 1 minute of illumination, which was followed by a gradual, prolonged decrease during the remainder of the induction period. Total leaf aspartate decreased initially, but temporarily doubled in amount between 5 and 10 minutes of illumination (after its surge as a primary product). These results are discussed in terms of a plausible sequence of metabolic events which lead to the formation of the intercellular metabolite gradients required in C 4 photosynthesis

  9. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C4 of the Plateau Pika (Ochotona curzoniae

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    Yang Wang

    2016-01-01

    Full Text Available Testis-specific lactate dehydrogenase (LDH-C4 is one of the lactate dehydrogenase (LDH isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C4 in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000–5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C4 in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A4 (LDH-A4, Lactate Dehydrogenase B4 (LDH-B4, and LDH-C4 were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE and native polyacrylamide gel electrophoresis (PAGE. The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km of LDH-C4 for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C4 for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki of the LDH isoenzymes varied: LDH-A4 (Ki = 26.900 mmol/L, LDH-B4 (Ki = 23.800 mmol/L, and LDH-C4 (Ki = 65.500 mmol/L. These data suggest that inhibition of lactate by LDH-A4 and LDH-B4 were stronger than LDH-C4. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C4.

  10. Metabolic Network Constrains Gene Regulation of C4 Photosynthesis: The Case of Maize.

    Science.gov (United States)

    Robaina-Estévez, Semidán; Nikoloski, Zoran

    2016-05-01

    Engineering C3 plants to increase their efficiency of carbon fixation as well as of nitrogen and water use simultaneously may be facilitated by understanding the mechanisms that underpin the C4 syndrome. Existing experimental studies have indicated that the emergence of the C4 syndrome requires co-ordination between several levels of cellular organization, from gene regulation to metabolism, across two co-operating cell systems-mesophyll and bundle sheath cells. Yet, determining the extent to which the structure of the C4 plant metabolic network may constrain gene expression remains unclear, although it will provide an important consideration in engineering C4 photosynthesis in C3 plants. Here, we utilize flux coupling analysis with the second-generation maize metabolic models to investigate the correspondence between metabolic network structure and transcriptomic phenotypes along the maize leaf gradient. The examined scenarios with publically available data from independent experiments indicate that the transcriptomic programs of the two cell types are co-ordinated, quantitatively and qualitatively, due to the presence of coupled metabolic reactions in specific metabolic pathways. Taken together, our study demonstrates that precise quantitative coupling will have to be achieved in order to ensure a successfully engineered transition from C3 to C4 crops. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

  11. Chronic effects of the ionic liquid [C4mim][Cl] towards the microalga Scenedesmus quadricauda

    International Nuclear Information System (INIS)

    Deng, Yun; Beadham, Ian; Wu, Jie; Chen, Xiao-Di; Hu, Lan; Gu, Jun

    2015-01-01

    Chronic effects of the ionic liquid [C 4 mim][Cl] (mp 73 °C) towards the microalga, Scenedesmus quadricauda were studied by flow cytometry, monitoring multiple endpoints of cell density, esterase activity, membrane integrity, reactive oxygen species and chlorophyll fluorescence. Toxicity was clearly in evidence, and although increased esterase activity indicated hormesis during initial exposure to [C 4 mim][Cl], inhibition of both esterase activity and chlorophyll fluorescence became apparent after 3 days. Cell density was also decreased by culturing with [C 4 mim][Cl], but this effect was clearly concentration-dependent and only became significant during the second half of the experiment. In contrast, [C 4 mim][Cl] had only a modest effect on reactive oxygen species (ROS) and caused little damage to cell membranes. - Highlights: • Use of an advanced biological technique, flow cytometry, to elucidate ionic liquid toxicity. • Chronic effects of ionic liquid. • Membrane integrity and ROS studied. • Mechanism of ionic liquid toxicity. - [C 4 mim][Cl] significantly inhibited esterase activity, chlorophyll fluorescence and cell density, having only a modest effect on reactive oxygen species and cell membranes

  12. Sistem Pakar Identifikasi Modalitas Belajar Siswa Dengan Implementasi Algoritma C4.5

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    Rachmawati Soewono

    2016-01-01

    Full Text Available C4.5 Algorithm is one of the classification technique in machine learning which is used in data mining process by build a decision tree which is represent in the rules. The aims of classification technique in data mining is to recognize the regularity of the pattern and the relation in a huge dataset by historical data collection. Students’ modalities measurement which is done by the questionnaire is produce historical data which is potentially to be processed to generate the classification that can be converted in rules. The expert acquisition and the C4.5 algorithm classification rules are used as knowledge base in the expert system. Therefore this research is done to build an expert system of the student’s modalities identification by implementing C4.5 algorithm that can produce seven categories of modalities classification, they are : visual, auditory, kinesthetic, visual-auditory, visual-kinesthetic, auditory-kinesthetic and visual-auditory-kinesthetic which has good in accuracy. The accuracy of the C4.5 algorithm classification and the expert system testing prediction is 80%. Keywords : Expert system; Decision tree; C4.5 Algorithm; Modalities.  

  13. Phenology and productivity of C3 and C4 grasslands in Hawaii.

    Science.gov (United States)

    Pau, Stephanie; Still, Christopher J

    2014-01-01

    Grasslands account for a large proportion of global terrestrial productivity and play a critical role in carbon and water cycling. Within grasslands, photosynthetic pathway is an important functional trait yielding different rates of productivity along environmental gradients. Recently, C3-C4 sorting along spatial environmental gradients has been reassessed by controlling for confounding traits in phylogenetically structured comparisons. C3 and C4 grasses should sort along temporal environmental gradients as well, resulting in differing phenologies and growing season lengths. Here we use 10 years of satellite data (NDVI) to examine the phenology and greenness (as a proxy for productivity) of C3 and C4 grass habitats, which reflect differences in both environment and plant physiology. We perform phylogenetically structured comparisons based on 3,595 digitized herbarium collections of 152 grass species across the Hawaiian Islands. Our results show that the clade identity of grasses captures differences in their habitats better than photosynthetic pathway. Growing season length (GSL) and associated productivity (GSP) were not significantly different when considering photosynthetic type alone, but were indeed different when considering photosynthetic type nested within clade. The relationship between GSL and GSP differed most strongly between C3 clade habitats, and not between C3-C4 habitats. Our results suggest that accounting for the interaction between phylogeny and photosynthetic pathway can help improve predictions of productivity, as commonly used C3-C4 classifications are very broad and appear to mask important diversity in grassland ecosystem functions.

  14. Phenology and productivity of C3 and C4 grasslands in Hawaii.

    Directory of Open Access Journals (Sweden)

    Stephanie Pau

    Full Text Available Grasslands account for a large proportion of global terrestrial productivity and play a critical role in carbon and water cycling. Within grasslands, photosynthetic pathway is an important functional trait yielding different rates of productivity along environmental gradients. Recently, C3-C4 sorting along spatial environmental gradients has been reassessed by controlling for confounding traits in phylogenetically structured comparisons. C3 and C4 grasses should sort along temporal environmental gradients as well, resulting in differing phenologies and growing season lengths. Here we use 10 years of satellite data (NDVI to examine the phenology and greenness (as a proxy for productivity of C3 and C4 grass habitats, which reflect differences in both environment and plant physiology. We perform phylogenetically structured comparisons based on 3,595 digitized herbarium collections of 152 grass species across the Hawaiian Islands. Our results show that the clade identity of grasses captures differences in their habitats better than photosynthetic pathway. Growing season length (GSL and associated productivity (GSP were not significantly different when considering photosynthetic type alone, but were indeed different when considering photosynthetic type nested within clade. The relationship between GSL and GSP differed most strongly between C3 clade habitats, and not between C3-C4 habitats. Our results suggest that accounting for the interaction between phylogeny and photosynthetic pathway can help improve predictions of productivity, as commonly used C3-C4 classifications are very broad and appear to mask important diversity in grassland ecosystem functions.

  15. Optional use of CAM photosynthesis in two C4 species, Portulaca cyclophylla and Portulaca digyna.

    Science.gov (United States)

    Holtum, Joseph A M; Hancock, Lillian P; Edwards, Erika J; Winter, Klaus

    2017-07-01

    Low levels of crassulacean acid metabolism (CAM) are demonstrated in two species with C 4 photosynthesis, Portulaca cyclophylla and P. digyna. The expression of CAM in P. cyclophylla and P. digyna is facultative, i.e. optional. Well-watered plants did not accumulate acid at night and exhibited gas-exchange patterns consistent with C 4 photosynthesis. CAM-type nocturnal acidification was reversible in that it was induced following drought and lost when droughted plants were rewatered. In P. cyclophylla, droughting was accompanied by a small but discernible net uptake of CO 2 during the dark, whereas in P. digyna, net CO 2 exchange at night approached the CO 2 compensation point but did not transition beyond it. This report brings the number of known C 4 species with a capacity for expressing CAM to six. All are species of Portulaca. The observation of CAM in P. cyclophylla and P. digyna is the first for species in the opposite-leaved (OL) Portulacelloid-anatomy lineage of Portulaca and for the Australian clade therein. The other four species are within the alternate-leaved (AL) lineage, in the Atriploid-anatomy Oleracea and the Pilosoid-anatomy Pilosa clades. Studies of the evolutionary origins of C 4 and CAM in Portulaca will benefit from a more wide-range survey of CAM across its species, particularly in the C 3 -C 4 intermediate-containing Cryptopetala clade. Copyright © 2017 Elsevier GmbH. All rights reserved.

  16. Identification of C4 photosynthesis metabolism and regulatory-associated genes in Eleocharis vivipara by SSH.

    Science.gov (United States)

    Chen, Taiyu; Ye, Rongjian; Fan, Xiaolei; Li, Xianghua; Lin, Yongjun

    2011-09-01

    This is the first effort to investigate the candidate genes involved in kranz developmental regulation and C(4) metabolic fluxes in Eleocharis vivipara, which is a leafless freshwater amphibious plant and possesses a distinct culms anatomy structure and photosynthetic pattern in contrasting environments. A terrestrial specific SSH library was constructed to investigate the genes involved in kranz anatomy developmental regulation and C(4) metabolic fluxes. A total of 73 ESTs and 56 unigenes in 384 clones were identified by array hybridization and sequencing. In total, 50 unigenes had homologous genes in the databases of rice and Arabidopsis. The real-time quantitative PCR results showed that most of the genes were accumulated in terrestrial culms and ABA-induced culms. The C(4) marker genes were stably accumulated during the culms development process in terrestrial culms. With respect to C(3) culms, C(4) photosynthesis metabolism consumed much more transporters and translocators related to ion metabolism, organic acids and carbohydrate metabolism, phosphate metabolism, amino acids metabolism, and lipids metabolism. Additionally, ten regulatory genes including five transcription factors, four receptor-like proteins, and one BURP protein were identified. These regulatory genes, which co-accumulated with the culms developmental stages, may play important roles in culms structure developmental regulation, bundle sheath chloroplast maturation, and environmental response. These results shed new light on the C(4) metabolic fluxes, environmental response, and anatomy structure developmental regulation in E. vivipara.

  17. Biochemical approaches to C4 photosynthesis evolution studies: the case of malic enzymes decarboxylases.

    Science.gov (United States)

    Saigo, Mariana; Tronconi, Marcos A; Gerrard Wheeler, Mariel C; Alvarez, Clarisa E; Drincovich, María F; Andreo, Carlos S

    2013-11-01

    C4 photosynthesis enables the capture of atmospheric CO2 and its concentration at the site of RuBisCO, thus counteracting the negative effects of low atmospheric levels of CO2 and high atmospheric levels of O2 (21 %) on photosynthesis. The evolution of this complex syndrome was a multistep process. It did not occur by simply recruiting pre-exiting components of the pathway from C3 ancestors which were already optimized for C4 function. Rather it involved modifications in the kinetics and regulatory properties of pre-existing isoforms of non-photosynthetic enzymes in C3 plants. Thus, biochemical studies aimed at elucidating the functional adaptations of these enzymes are central to the development of an integrative view of the C4 mechanism. In the present review, the most important biochemical approaches that we currently use to understand the evolution of the C4 isoforms of malic enzyme are summarized. It is expected that this information will help in the rational design of the best decarboxylation processes to provide CO2 for RuBisCO in engineering C3 species to perform C4 photosynthesis.

  18. Artificial intelligence approaches in statistics

    International Nuclear Information System (INIS)

    Phelps, R.I.; Musgrove, P.B.

    1986-01-01

    The role of pattern recognition and knowledge representation methods from Artificial Intelligence within statistics is considered. Two areas of potential use are identified and one, data exploration, is used to illustrate the possibilities. A method is presented to identify and separate overlapping groups within cluster analysis, using an AI approach. The potential of such ''intelligent'' approaches is stressed

  19. Immune complex detection and complement activity in rheumatoid arthritis: a comparative study of a radioimmunoassay using monoclonal rheumatoid factor, gel diffusion techniques and C4 activity

    International Nuclear Information System (INIS)

    Halla, J.T.; Volanakis, J.E.; Hardin, J.G.; Schrohenloher, R.E.

    1978-01-01

    Paired sera and synovial fluids from 49 patients with rheumatoid arthritis and 25 with other forms of arthritis were tested for immune complexes by a radioimmunoassay using monoclonal rheumatoid factor and gel diffusion procedures with monoclonal rheumatoid factor and Clq. Synovial fluid hemolytic C4 and C4 adjusted for IgG concentration were determined in both groups of patients. Immune complexes were detected at similar high frequencies in the rheumatoid synovial fluids by precipitin formation with monoclonal rheumatoid factor (68%) and Clq (71%). In contrast, immune complexes in rheumatoid sere were detected in low frequency by precipitin reactions with monoclonal rheumatoid factor (10%) and Clq (0%). Using the monoclonal rheumatoid factor radioimmunoassay, thirty-one (63%) synovial fluids exceeded the mean non-RA binding activity by one standard deviation. Synovial fluid C4 adjusted for IgG as well as IgG alone distinguished between the two groups of patients whereas the C4 did not. The C4/IgG value showed a strong negative correlation with the monoclonal rheumatoid factor radioimmunoassay and Clq precipitin formation. (author)

  20. Quantification of C4d deposition and hepatitis C virus RNA in tissue in cases of graft rejection and hepatitis C recurrence after liver transplantation

    Directory of Open Access Journals (Sweden)

    Alice Tung Wan Song

    2015-02-01

    Full Text Available Histology is the gold standard for diagnosing acute rejection and hepatitis C recurrence after liver transplantation. However, differential diagnosis between the two can be difficult. We evaluated the role of C4d staining and quantification of hepatitis C virus (HCV RNA levels in liver tissue. This was a retrospective study of 98 liver biopsy samples divided into four groups by histological diagnosis: acute rejection in patients undergoing liver transplant for hepatitis C (RejHCV+, HCV recurrence in patients undergoing liver transplant for hepatitis C (HCVTx+, acute rejection in patients undergoing liver transplant for reasons other than hepatitis C and chronic hepatitis C not transplanted (HCVTx-. All samples were submitted for immunohistochemical staining for C4d and HCV RNA quantification. Immunoexpression of C4d was observed in the portal vessels and was highest in the HCVTx- group. There was no difference in C4d expression between the RejHCV+ and HCVTx+ groups. However, tissue HCV RNA levels were higher in the HCVTx+ group samples than in the RejHCV+ group samples. Additionally, there was a significant correlation between tissue and serum levels of HCV RNA. The quantification of HCV RNA in liver tissue might prove to be an efficient diagnostic test for the recurrence of HCV infection.

  1. Intracellular position of mitochondria in mesophyll cells differs between C3and C4grasses.

    Science.gov (United States)

    Hatakeyama, Yuto; Ueno, Osamu

    2017-09-01

    In C 3 plants, part of the CO 2 fixed during photosynthesis in chloroplasts is released from mitochondria during photorespiration by decarboxylation of glycine via glycine decarboxylase (GDC), thereby reducing photosynthetic efficiency. The apparent positioning of most mitochondria in the interior (vacuole side of chloroplasts) of mesophyll cells in C 3 grasses would increase the efficiency of refixation of CO 2 released from mitochondria by ribulose 1,5-bisphosphate carboxylase/​oxygenase (Rubisco) in chloroplasts. Therefore, in mesophyll cells of C 4 grasses, which lack both GDC and Rubisco, the mitochondria ought not to be positioned the same way as in C 3 mesophyll cells. To test this hypothesis, we investigated the intracellular position of mitochondria in mesophyll cells of 14 C 4 grasses of different C 4 subtypes and subfamilies (Chloridoideae, Micrairoideae, and Panicoideae) and a C 3 -C 4 intermediate grass, Steinchisma hians, under an electron microscope. In C 4 mesophyll cells, most mitochondria were positioned adjacent to the cell wall, which clearly differs from the positioning in C 3 mesophyll cells. In S. hians mesophyll cells, the positioning was similar to that in C 3 cells. These results suggest that the mitochondrial positioning in C 4 mesophyll cells reflects the absence of both GDC and Rubisco in the mesophyll cells and the high activity of phosphoenolpyruvate carboxylase. In contrast, the relationship between the mitochondrial positioning and enzyme distribution in S. hians is complex, but the positioning may be related to the capture of respiratory CO 2 by Rubisco. Our study provides new possible insight into the physiological role of mitochondrial positioning in photosynthetic cells.

  2. Significant accumulation of C(4)-specific pyruvate, orthophosphate dikinase in a C(3) plant, rice.

    Science.gov (United States)

    Fukayama, H; Tsuchida, H; Agarie, S; Nomura, M; Onodera, H; Ono, K; Lee, B H; Hirose, S; Toki, S; Ku, M S; Makino, A; Matsuoka, M; Miyao, M

    2001-11-01

    The C(4)-Pdk gene encoding the C(4) enzyme pyruvate, orthophosphate dikinase (PPDK) of maize (Zea mays cv Golden Cross Bantam) was introduced into the C(3) plant, rice (Oryza sativa cv Kitaake). When the intact maize C(4)-Pdk gene, containing its own promoter and terminator sequences and exon/intron structure, was introduced, the PPDK activity in the leaves of some transgenic lines was greatly increased, in one line reaching 40-fold over that of wild-type plants. In a homozygous line, the PPDK protein accounted for 35% of total leaf-soluble protein or 16% of total leaf nitrogen. In contrast, introduction of a chimeric gene containing the full-length cDNA of the maize PPDK fused to the maize C(4)-Pdk promoter or the rice Cab promoter only increased PPDK activity and protein level slightly. These observations suggest that the intron(s) or the terminator sequence of the maize gene, or a combination of both, is necessary for high-level expression. In maize and transgenic rice plants carrying the intact maize gene, the level of transcript in the leaves per copy of the maize C(4)-Pdk gene was comparable, and the maize gene was expressed in a similar organ-specific manner. These results suggest that the maize C(4)-Pdk gene behaves in a quantitatively and qualitatively similar way in maize and transgenic rice plants. The activity of the maize PPDK protein expressed in rice leaves was light/dark regulated as it is in maize. This is the first reported evidence for the presence of an endogenous PPDK regulatory protein in a C(3) plant.

  3. Environmental change and hominin exploitation of C4-based resources in wetland/savanna mosaics.

    Science.gov (United States)

    Stewart, Kathlyn M

    2014-12-01

    Eastern and southern Africa experienced ongoing climatic and tectonic instability in the Plio-Pleistocene, alongside declining forests and expanding grasslands. Most known hominin genera (Australopithecus spp., Kenyanthropus, Paranthropus spp., Homo spp.) appear roughly between 4.2 and 1.8 Ma (millions of years ago). Explanations for these speciation events have focused on adaptations to environmental change, particularly in terrestrial biomes. However, the links between environmental change and hominin adaptations have not always been clear. Often overlooked is that Plio-Pleistocene vegetation included not just terrestrial environments, but a large component of edaphic (wet) C4 grasses and sedges. In this paper it is suggested that in response to environmental fluctuations, hominins engaged in conservative long-term ecological and dietary patterns, based on predictable C4/C3 wetland and terrestrial resources. Data are presented from six hominin locales, which demonstrate reliance on plant-based resources (sedges, grasses, and other vegetation) in C4-inclusive wetland/savanna mosaics. After roughly 2.4 Ma, severe climate variability is associated with early Homo and perhaps Paranthropus boisei broadening their diet to familiar but less preferred foods: vertebrates and invertebrates. These foods consistently provided early Homo with essential nutrients, which reduced selection pressures and allowed for increases in brain size. After 1.65 Ma, a 20% increase in the C4 dietary component of Homo occurs alongside increased relative brain size. P. boisei also increases its C4 dietary component by 15% after 1.65 Ma. These increases imply that both taxa continued to broaden their diet within the C4-based wetlands/savanna biome, with Homo putting a greater emphasis on mammals. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  4. Isolation of dimorphic chloroplasts from the single-cell C4 species Bienertia sinuspersici

    Directory of Open Access Journals (Sweden)

    Lung Shiu-Cheung

    2012-03-01

    Full Text Available Abstract Three terrestrial plants are known to perform C4 photosynthesis without the dual-cell system by partitioning two distinct types of chloroplasts in separate cytoplasmic compartments. We report herein a protocol for isolating the dimorphic chloroplasts from Bienertia sinuspersici. Hypo-osmotically lysed protoplasts under our defined conditions released intact compartments containing the central chloroplasts and intact vacuoles with adhering peripheral chloroplasts. Following Percoll step gradient purification both chloroplast preparations demonstrated high homogeneities as evaluated from the relative abundance of respective protein markers. This protocol will open novel research directions toward understanding the mechanism of single-cell C4 photosynthesis.

  5. Four-dimensional gravitational backgrounds based on N = 4, $\\widehat{c}$ = 4, superconformal systems

    CERN Document Server

    Kounnas, Costas

    1994-01-01

    We propose two new realizations of the N=4, $\\hat{c}=4$ superconformal system based on the compact and non-compact versions of parafermionic algebras. The target space interpretation of these systems is given in terms of four-dimensional target spaces with non-trivial metric and topology different from the previously known four-dimensional semi-wormhole realization. The proposed $\\hat{c}=4$ systems can be used as a building block to construct perturbatively stable superstring solutions with covariantized target space supersymmetry around non-trivial gravitational and dilaton backgrounds.

  6. Diversity in forms of C4 in the genus Cleome (Cleomaceae)

    Science.gov (United States)

    Koteyeva, Nuria K.; Voznesenskaya, Elena V.; Roalson, Eric H.; Edwards, Gerald E.

    2011-01-01

    Background and Aims Cleomaceae is one of 19 angiosperm families in which C4 photosynthesis has been reported. The aim of the study was to determine the type, and diversity, of structural and functional forms of C4 in genus Cleome. Methods Plants of Cleome species were grown from seeds, and leaves were subjected to carbon isotope analysis, light and scanning electron microscopy, western blot analysis of proteins, and in situ immunolocalization for ribulose bisphosphate carboxylase oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC). Key Results Three species with C4-type carbon isotope values occurring in separate lineages in the genus (Cleome angustifolia, C. gynandra and C. oxalidea) were shown to have features of C4 photosynthesis in leaves and cotyledons. Immunolocalization studies show that PEPC is localized in mesophyll (M) cells and Rubisco is selectively localized in bundle sheath (BS) cells in leaves and cotyledons, characteristic of species with Kranz anatomy. Analyses of leaves for key photosynthetic enzymes show they have high expression of markers for the C4 cycle (compared with the C3–C4 intermediate C. paradoxa and the C3 species C. africana). All three are biochemically NAD-malic enzyme sub-type, with higher granal development in BS than in M chloroplasts, characteristic of this biochemical sub-type. Cleome gynandra and C. oxalidea have atriplicoid-type Kranz anatomy with multiple simple Kranz units around individual veins. However, C. angustifolia anatomy is represented by a double layer of concentric chlorenchyma forming a single compound Kranz unit by surrounding all the vascular bundles and water storage cells. Conclusions NAD-malic enzyme-type C4 photosynthesis evolved multiple times in the family Cleomaceae, twice with atriplicoid-type anatomy in compound leaves having flat, broad leaflets in the pantropical species C. gynandra and the Australian species C. oxalidea, and once by forming a single Kranz unit in compound leaves with

  7. Investigating C4 Grass Contributions to N-alkane Based Paleoclimate Reconstructions

    Science.gov (United States)

    Doman, C. E.; Enders, S. K.; Chadwick, O.; Freeman, K. H.

    2014-12-01

    Plant wax n-alkanes are long-chain, saturated hydrocarbons contained within the protective waxy cuticle on leaves. These lipids are pervasive and persistent in soils and sediments and thus are ideal biomarkers of ancient terrestrial organic matter. In ecosystems dominated by C3 plants, the relationship between the carbon isotopic value of whole leaves and lipids is fairly well documented, but this relationship has not been fully investigated for plants that use C4 photosynthesis. In both cases, it is unclear if the isotopic relationships are sensitive to environmental conditions, or reflect inherited characteristics. This study used a natural climate gradient on the Kohala peninsula of Hawaii to investigate relationships between climate and the δ13C and δ2H values of n-alkanes in C3 and C4 plants. δ13C of C3 leaves and lipids decreased 5 ‰ from the driest to the wettest sites, consistent with published data. Carbon isotope values of C4 plants showed no relationship to moisture up to 1000 mm mean annual precipitation (MAP). Above this threshold, δ 13C values were around 10‰ more depleted, likely due to a combination of canopy effects and C4 grasses growing in an uncharacteristically wet and cold environment. In C3 plants, the fractionation between leaf and lipid carbon isotopes did not vary with MAP, which allows estimations of δ13C leaf to be made from alkanes preserved in ancient sediments. Along this transect, C3 plants produce around twice the quantity of n-alkanes as C4 grasses. C4 grasses produce longer carbon chains. As a result, n-alkanes in the geologic record will be biased towards C3 plants, but the presence of alkanes C33 and C35 indicate the contributions of C4 grasses. In both C3 and C4 plants, average chain length increased with mean annual precipitation, but the taxonomic differences in chain length were greater than environmental differences. Hydrogen isotopes of n-alkanes show no trends with MAP, but do show clear differences between plant

  8. C# 4, ASP.NET 4, and WPF, with Visual Studio 2010 jump start

    CERN Document Server

    Nagel, Christian; Stephens, Rod; Hanselman, Scott; Glynn, Jay; Rader, Devin; Watson, Karli; Skinner, Morgan

    2010-01-01

    This Wrox Blox is a value-packed resource to help experienced .NETdevelopers learn the new .NET release. It is excerpted from theWrox books: Professional C# 4 and .NET 4, Professional ASP.NET4, and WPF Programmer's Reference by Christian Nagel,Bill Evjen, Scott Hanselman, and Rod Stephens, and includes morethan 100 print book pages drawn from these three key titles. It isan excellent resource to help .NET developers get up to speed faston .NET 4, C# 4.0, ASP.NET 4, and WPF, providing all theinformation needed to program with the important new features,including: C# Dynamic Types and Par

  9. The urokinase receptor and its structural homologue C4.4A in human cancer

    DEFF Research Database (Denmark)

    Jacobsen, B; Ploug, M

    2008-01-01

    The urokinase-type plasminogen activator receptor (uPAR) and its structural homologue C4.4A are multidomain members of the Ly6/uPAR/alpha-neurotoxin protein domain family. Both are glycosylphosphatidylinositol-anchored membrane glycoproteins encoded by neighbouring genes located on chromosome 19q13...... in a number of human cancers including colon adenocarcinoma and pulmonary squamous cell carcinoma. Targeting uPAR in experimental animal models has also provided promising results regarding the interference with pathogenic plasminogen activation. In the case of C4.4A, very recent data have demonstrated...

  10. Arquitectura de un sistema C4ISR para pequeñas unidades.

    OpenAIRE

    Pérez Llopis, Israel

    2011-01-01

    La presente tesis doctoral aborda el problema de los sistemas de mando y control, y en concreto los sistemas C4ISR. Los sistemas C4ISr (Command Control, Computers and Communications Information Surveillance and Reconaissance) engloban un amplio número de arquitecturas y sistemas informáticos y de comunicaciones. Su principal finalidad, tanto en aplicaciones civiles como militares, es la de obtener información sobre el estado del teatro de operaciones para entregársela, convenientemente format...

  11. Artificial Disc Replacement

    Science.gov (United States)

    ... Spondylolisthesis BLOG FIND A SPECIALIST Treatments Artificial Disc Replacement (ADR) Patient Education Committee Jamie Baisden The disc ... Disc An artificial disc (also called a disc replacement, disc prosthesis or spine arthroplasty device) is a ...

  12. Trends in Artificial Intelligence.

    Science.gov (United States)

    Hayes, Patrick

    1978-01-01

    Discusses the foundations of artificial intelligence as a science and the types of answers that may be given to the question, "What is intelligence?" The paradigms of artificial intelligence and general systems theory are compared. (Author/VT)

  13. Artificial Hydration and Nutrition

    Science.gov (United States)

    ... Crisis Situations Pets and Animals myhealthfinder Food and Nutrition Healthy Food Choices Weight Loss and Diet Plans ... Your Health Resources Healthcare Management Artificial Hydration and Nutrition Artificial Hydration and Nutrition Share Print Patients who ...

  14. Artificial life and Piaget.

    Science.gov (United States)

    Mueller, Ulrich; Grobman, K H.

    2003-04-01

    Artificial life provides important theoretical and methodological tools for the investigation of Piaget's developmental theory. This new method uses artificial neural networks to simulate living phenomena in a computer. A recent study by Parisi and Schlesinger suggests that artificial life might reinvigorate the Piagetian framework. We contrast artificial life with traditional cognitivist approaches, discuss the role of innateness in development, and examine the relation between physiological and psychological explanations of intelligent behaviour.

  15. Controlling Functional Group Architecture in Artificial Cells

    Science.gov (United States)

    2015-07-02

    coumarin dyes. We provided evidence for restricting modification to the inner and outer leaflet of the lipid membranes. Data was generated by high...performance liquid chromatography and fluorescence microscopy. Using the coumarin probe, we were able to show how the nature of the reactive elements

  16. Unusual transport behaviour of actinide ions with a novel calix(4)arene-tetra-diglycolamide (C4DGA) extractant as the carrier

    NARCIS (Netherlands)

    Mohapatra, P.K.; Iqbal, M.; Raut, D.R.; Huskens, Jurriaan; Verboom, Willem

    2012-01-01

    A calix[4]arene appended with four diglycolamide moieties containing n-octyl groups (C4DGA) was evaluated for the transport of actinide ions such as UO22+, Pu4+, Pu3+, and Am3+ from acidic feed solutions across PTFE flat sheet supported liquid membranes. The supported liquid membrane (SLM) studies

  17. artificial neural network (ann)

    African Journals Online (AJOL)

    2004-08-18

    Aug 18, 2004 ... forecasting models and artificial intelligence techniques and have become one of the major research fields (Kher and Joshin, 2003). (a) Artificial Neural Network and Electrical Load. Prediction. Neural network analysis is an Artificial Intelligence. (AI) approach to mathematical modeling. Neural. Networks ...

  18. Methodology Investigation of AI(Artificial Intelligence) Test Officer Support Tool. Volume 1

    Science.gov (United States)

    1989-03-01

    American Association for Artificial inteligence A! ............. Artificial inteliigence AMC ............ Unt:ed States Army Maeriel Comand ASL...block number) FIELD GROUP SUB-GROUP Artificial Intelligence, Expert Systems Automated Aids to Testing 9. ABSTRACT (Continue on reverse if necessary and...identify by block number) This report covers the application of Artificial Intelligence-Techniques to the problem of creating automated tools to

  19. Integration of C4-specific ppdk gene of Echinochloa to C3 upland ...

    African Journals Online (AJOL)

    SERVER

    2008-03-18

    Mar 18, 2008 ... rice though increased photoinhibition was noted under high light intensity. Key words: Pyrurate ... PPDK is regarded as an important target in efforts to .... transgenic upland rice. The introduction of C4 photosynthetic enzyme into C3 plants was intended to improve the efficiency of solar energy utilization.

  20. Interrelations between C4 ketogenesis, C5 ketogenesis, and anaplerosis in the perfused rat liver.

    Science.gov (United States)

    Deng, Shuang; Zhang, Guo-Fang; Kasumov, Takhar; Roe, Charles R; Brunengraber, Henri

    2009-10-09

    We investigated the interrelations between C(4) ketogenesis (production of beta-hydroxybutyrate + acetoacetate), C(5) ketogenesis (production of beta-hydroxypentanoate + beta-ketopentanoate), and anaplerosis in isolated rat livers perfused with (13)C-labeled octanoate, heptanoate, or propionate. Mass isotopomer analysis of C(4) and C(5) ketone bodies and of related acyl-CoA esters reveal that C(4) and C(5) ketogenesis share the same pool of acetyl-CoA. Although the uptake of octanoate and heptanoate by the liver are similar, the rate of C(5) ketogenesis from heptanoate is much lower than the rate of C(4) ketogenesis from octanoate. This results from the channeling of the propionyl moiety of heptanoate into anaplerosis of the citric acid cycle. C(5) ketogenesis from propionate is virtually nil because acetoacyl-CoA thiolase does not favor the formation of beta-ketopentanoyl-CoA from propionyl-CoA and acetyl-CoA. Anaplerosis and gluconeogenesis from heptanoate are inhibited by octanoate. The data have implications for the design of diets for the treatment of long chain fatty acid oxidation disorders, such as the triheptanoin-based diet.

  1. Interrelations between C4 Ketogenesis, C5 Ketogenesis, and Anaplerosis in the Perfused Rat Liver*

    Science.gov (United States)

    Deng, Shuang; Zhang, Guo-Fang; Kasumov, Takhar; Roe, Charles R.; Brunengraber, Henri

    2009-01-01

    We investigated the interrelations between C4 ketogenesis (production of β-hydroxybutyrate + acetoacetate), C5 ketogenesis (production of β-hydroxypentanoate + β-ketopentanoate), and anaplerosis in isolated rat livers perfused with 13C-labeled octanoate, heptanoate, or propionate. Mass isotopomer analysis of C4 and C5 ketone bodies and of related acyl-CoA esters reveal that C4 and C5 ketogenesis share the same pool of acetyl-CoA. Although the uptake of octanoate and heptanoate by the liver are similar, the rate of C5 ketogenesis from heptanoate is much lower than the rate of C4 ketogenesis from octanoate. This results from the channeling of the propionyl moiety of heptanoate into anaplerosis of the citric acid cycle. C5 ketogenesis from propionate is virtually nil because acetoacyl-CoA thiolase does not favor the formation of β-ketopentanoyl-CoA from propionyl-CoA and acetyl-CoA. Anaplerosis and gluconeogenesis from heptanoate are inhibited by octanoate. The data have implications for the design of diets for the treatment of long chain fatty acid oxidation disorders, such as the triheptanoin-based diet. PMID:19666922

  2. Response to elevated CO 2 from a natural spring in a C 4 ...

    African Journals Online (AJOL)

    Eragrostis racemosa (C4), a slow grower, showed no significant responses to high CO2 during the late season. CO2-responsiveness in the field generally followed the seasonal phenologies of each species, being greatest during the most active growth period. Keywords: climate change; gas exchange; photosynthetic ...

  3. PENERAPAN ALGORITMA C4.5 UNTUK PREDIKSI PENGGUNAAN JENIS KONTRASEPSI BERBASIS WEB

    Directory of Open Access Journals (Sweden)

    Rusda Wajhillah

    2017-09-01

    Keluarga Berencana (KB merupakan suatu program pemerintah yang dirancang untuk menyeimbangkan antara kebutuhan dan jumlah penduduk dengan menggunakan alat kontrasepsi. Kurangnya pengetahuan tentang kontrasepsi menyebabkan tidak sedikit akseptor lebih memilih menggunakan kontrasepsi berdasarkan coba-coba atau bahkan mengikuti saran dari orang lain yang kurang paham terhadap alat kontrasepsi. Oleh sebab itu, diperlukan adanya tindakan/penanganan khusus untuk mempermudah para akseptor dalam memilih kontrasepsi yang efektif dan sesuai dengan kondisi tubuhnya. Algoritma C4.5 yaitu metode pohon keputusan mengubah fakta yang sangat besar menjadi pohon keputusan yang merepresentasikan aturan. Aturan dapat dengan mudah dipahami dengan bahasa alami.Untuk itu, dalam penelitian ini akan dilakukan analisa data penggunaan jenis kontrasepsi menggunakan klasifikasi data mining yakni algoritma C4.5 dengan menggunakan beberapa parameter diantaranya usia, jumlah anak, tekanan darah dan riwayat penyakit yang akan diaplikasikan dalam bentuk web guna mempermudah para akseptor dalam mendapatkan nilai informasi yang lebih cepat dan fleksibel. Dari 130 jumlah kasus yang terdiri dari 104 kasus akseptor pengguna kontrasepsi hormonal dan 26 kasus pengguna kontrasepsi non hormonal yang didapat dari Posyandu Desa Nyangkowek Kecamatan Cicurug, maka didapatkan 14 rule yang dihasilkan dari pohon keputusan algoritma C4.5 dengan jumlah class non hormonal sebanyak 8 rule dan jumlah class hormonal sebanyak 6 rule serta dievaluasi dengan pengujian Cross Validation yangmenghasilkan tingkat akurasi sebesar 85,38%, sehingga dapat disimpulkan bahwa penelitian ini dapat membantu para akseptor KB dalam memilih jenis kontrasepsi yang efektif. Kata Kunci: Akseptor, Algoritma C4.5, Kontrasepsi, Sistem Pakar

  4. 26 CFR 1.613A-5 - Election under section 613A(c)(4).

    Science.gov (United States)

    2010-04-01

    ... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613A-5 Election under section 613A(c)(4... percentage depletion deductions for the taxable year based upon such election. The election may be made, on... claim for credit or refund. The election allows the taxpayer to treat as his depletable natural gas...

  5. C4N2 ice in Titan’s atmosphere: reality or myth?

    Science.gov (United States)

    Anderson, Carrie; Samuelson, Robert E.; Achterberg, Richard K.; Flasar, F. M.

    2014-11-01

    Voyager 1 IRIS detected a spectral emission feature at 478 cm-1 in Titan’s atmosphere at high northern latitudes. Now one Titan year later we rediscovered it in Cassini CIRS limb spectra at 70°N. Thus far the feature has always been associated with the lower polar stratosphere during early northern spring. No known trace organic vapor in Titan’s atmosphere has a spectral feature at 478 cm-1, and the only known or suspected condensate that does is C4N2 ice. However, the C4N2 ν8 and ν9 vapor features at 472 cm-1 and 108 cm-1, respectively, have never been observed in Titan’s atmosphere, leading to a C4N2 vapor upper limit at least 2 orders of magnitude lower than equilibrium with the ice phase would suggest. In this study we analyze the spectral shapes and strengths of the 478 cm-1 feature in the IRIS and CIRS data sets in an effort to determine particle sizes, mole fractions, and vertical distributions of the putative condensate cloud responsible for the feature, and then discuss the pros and cons of its identify with C4N2 ice.

  6. Study of RS data classification based on rough sets and C4.5 algorithm

    Science.gov (United States)

    Yu, Ming; Ai, Ting-hua

    2009-10-01

    The classification by extracting of remote sensing (RS) data is the primary information source for GIS in land resource application. Automatic and accurate mapping of region LUCC from high spatial resolution satellite image is still a challenge. The paper discussed remote sensing image data classification techniques based on C4.5 algorithm and rough sets and the combination of C4.5 algorithm and rough sets. On the basis of the theories and methods of spatial data mining, we improve the classification accuracy. Finally validates its effectiveness taking a test area as example. We took the outskirts of Fuzhou with complicated land use in Fujian Province as study area. The classification rules are discovered from the samples through decision tree C4.5 algorithm, Rough Sets and both with together, which integrates spectral, textural and the topography characters. And the classification test is performed based on these rules. The traditional maximum likelihood classification is also compared to check the classification accuracy. The results have shown that the accuracy of classification based on knowledge is markedly higher than the traditional maximum likelihood classification. Especially the method based on combine Rough Sets and decision tree C4.5 algorithm is the best.

  7. Structural analysis and tissue localization of human C4.4A

    DEFF Research Database (Denmark)

    Hansen, Line V.; Gårdsvoll, Henrik; Nielsen, Boye S

    2004-01-01

    recombinant human C4.4A is extensively modified by post-translational glycosylation, which include 5-6 N-linked carbohydrates primarily located in or close to its second Ly-6/uPAR/alpha-neurotoxin module and approximately 15 O-linked carbohydrates clustered in a Ser/Thr/Pro-rich region at the C...

  8. Isotopic evidence for an early shift to C4 resources by Pliocene hominins in Chad

    Science.gov (United States)

    Lee-Thorp, Julia; Likius, Andossa; Mackaye, Hassane T.; Vignaud, Patrick; Sponheimer, Matt; Brunet, Michel

    2012-01-01

    Foods derived from C4 plants were important in the dietary ecology of early Pleistocene hominins in southern and eastern Africa, but the origins and geographic variability of this relationship remain unknown. Carbon isotope data show that Australopithecus bahrelghazali individuals from Koro Toro in Chad are significantly enriched in 13C, indicating a dependence on C4 resources. As these sites are over 3 million years in age, the results extend the pattern of C4 dependence seen in Paranthropus boisei in East Africa by more than 1.5 million years. The Koro Toro hominin fossils were found in argillaceous sandstone levels along with abundant grazing and aquatic faunal elements that, in combination, indicate the presence of open to wooded grasslands and stream channels associated with a greatly enlarged Lake Chad. In such an environment, the most abundant C4 plant resources available to A. bahrelghazali were grasses and sedges, neither of which is usually considered as standard great ape fare. The results suggest an early and fundamental shift in hominin dietary ecology that facilitated the exploitation of new habitats. PMID:23150583

  9. C4.4A as a biomarker in pulmonary adenocarcinoma and squamous cell carcinoma

    DEFF Research Database (Denmark)

    Jacobsen, Benedikte; Kriegbaum, Mette Camilla; Santoni-Rugiu, Eric

    2014-01-01

    The high prevalence and mortality of lung cancer, together with a poor 5-year survival of only approximately 15%, emphasize the need for prognostic and predictive factors to improve patient treatment. C4.4A, a member of the Ly6/uPAR family of membrane proteins, qualifies as such a potential infor...

  10. Optimization of C4.5 algorithm-based particle swarm optimization for breast cancer diagnosis

    Science.gov (United States)

    Muslim, M. A.; Rukmana, S. H.; Sugiharti, E.; Prasetiyo, B.; Alimah, S.

    2018-03-01

    Data mining has become a basic methodology for computational applications in the field of medical domains. Data mining can be applied in the health field such as for diagnosis of breast cancer, heart disease, diabetes and others. Breast cancer is most common in women, with more than one million cases and nearly 600,000 deaths occurring worldwide each year. The most effective way to reduce breast cancer deaths was by early diagnosis. This study aims to determine the level of breast cancer diagnosis. This research data uses Wisconsin Breast Cancer dataset (WBC) from UCI machine learning. The method used in this research is the algorithm C4.5 and Particle Swarm Optimization (PSO) as a feature option and to optimize the algorithm. C4.5. Ten-fold cross-validation is used as a validation method and a confusion matrix. The result of this research is C4.5 algorithm. The particle swarm optimization C4.5 algorithm has increased by 0.88%.

  11. Contribution of root respiration to soil respiration in a C3/C4 mixed ...

    Indian Academy of Sciences (India)

    The spatial and temporal variations of soil respiration were studied from May 2004 to June 2005 in a C3/C4 mixed grassland of Japan. The linear regression relationship between soil respiration and root biomass was used to determine the contribution of root respiration to soil respiration. The highest soil respiration rate of ...

  12. Identification of C2-C4 alkylated benzenes in flash pyrolysates of kerogens, coals and asphaltenes

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Hartgers, W.A.; Leeuw, J.W. de

    1992-01-01

    Pseudo-Kováts indices were determined for all positional isomers of C2-C4 alkylated benzenes using a non-polar capillary column (CP Sil-5). These indices were applied in combination with mass spectral data to identify these compounds in complex mixtures of a relatively non-polar nature generated

  13. Tomato yellow leaf curl virus C4 protein is a determinant of disease phenotype in tomato

    Science.gov (United States)

    Tomato yellow leaf curl virus (TYLCV) is a monopartite begomovirus. Its genome contains six open reading frames, with V1 and V2 in sense, and C1 to C4 in complementary orientation. The functions of V1 and V2 are for coat protein and pre-coat, respectively. C1 is for virus replication, C2 for trans-a...

  14. Serum Complement C3 and C4 Levels in Relation to Diagnosis of ...

    African Journals Online (AJOL)

    Purpose: The main objective of this study was to measure serum complement C3 and C4 concentrations in patients of lupus nephritis to see if these simple measurements would give useful information to the clinician managing such patients.Method: A total of 52 samples were obtained from SLE patients, 17 suffering from ...

  15. Nitrogen washing from C3 and C4 cover grasses residues by rain

    Directory of Open Access Journals (Sweden)

    Ciro Antonio Rosolem

    2010-12-01

    Full Text Available Crop species with the C4 photosynthetic pathway are more efficient in assimilating N than C3 plants, which results in different N amounts prone to be washed from its straw by rain water. Such differences may affect N recycling in agricultural systems where these species are grown as cover crops. In this experiment, phytomass production and N leaching from the straw of grasses with different photosynthetic pathways were studied in response to N application. Pearl millet (Pennisetum glaucum and congo grass (Brachiaria ruziziensis with the C4 photosynthetic pathway, and black oat (Avena Strigosa and triticale (X Triticosecale, with the C3 photosynthetic pathway, were grown for 47 days. After determining dry matter yields and N and C contents, a 30 mm rainfall was simulated over 8 t ha-1 of dry matter of each plant residue and the leached amounts of ammonium and nitrate were determined. C4 grasses responded to higher fertilizer rates, whereas N contents in plant tissue were lower. The amount of N leached from C4 grass residues was lower, probably because the C/N ratio is higher and N is more tightly bound to organic compounds. When planning a crop rotation system it is important to take into account the difference in N release of different plant residues which may affect N nutrition of the subsequent crop.

  16. Contribution of root respiration to soil respiration in a C3/C4 mixed ...

    Indian Academy of Sciences (India)

    Unknown

    The spatial and temporal variations of soil respiration were studied from May 2004 to June 2005 in a C3/C4 mixed grassland of Japan. The linear regression relationship between soil respiration and root biomass was used to determine the contribution of root respiration to soil respiration. The highest soil respiration rate of.

  17. The scheme for integration of satellite-based C4ISR system

    Science.gov (United States)

    Chen, Zhenyu; Meng, Yan; Chen, Yanhong

    2005-11-01

    This paper presents a technical scheme for the integrating of all types of strategic and tactical C4ISR systems through special satellite communication network and proposes information collection and distribution integrating networking scheme. The implementations of compatibility and interoperability of integrated system is described, and also anti-jamming features, covertness, and nuclear survivability are discussed.

  18. Photosynthetic plasticity in Flaveria brownii: Growth irradiance and the expression of C4 photosynthesis

    International Nuclear Information System (INIS)

    Cheng, Shuhua; Moore, B.D.; Wu, Jingrui; Edwards, G.E.; Ku, M.S.B.

    1989-01-01

    Photosynthesis was examined in leaves of Flaveria brownii A. M. Powell, grown under either 14% or 100% full sunlight. In leaves of high light grown plants, the CO 2 compensation point and the inhibition of photosynthesis by 21% O 2 were significantly lower, while activities of ribulose 1,5-bisphosphate carboxylase/oxygenase and various C 4 cycle enzymes were considerably higher than those in leaves grown in low light. Both the CO 2 compensation point and the degree of O 2 inhibition of apparent photosynthesis were relatively insensitive to the light intensity used during measurements with plants from either growth conditions. Partitioning of atmospheric CO 2 between Rubisco of the C 3 pathway and phosphoenolpyruvate carboxylase of the C 4 cycle was determined by exposing leaves to 14 CO 2 for 3 to 16 seconds, and extrapolating the labeling curves of initial products to zero time. Results indicated that ∼94% of the CO 2 was fixed by the C 4 cycle in high light grown plants, versus ∼78% in low light grown plants. Consistent with the carbon partitioning patterns, photosynthetic enzyme activities (on a chlorophyll basis) in protoplasts from leaves of high light grown plants showed a more C 4 -like pattern of compartmentation. Pyruvate,Pi dikinase and phosphoenolpyruvate carboxylase were more enriched in the mesophyll cells, while NADP-malic enzyme and ribulose 1,5-bisphosphate carboxylase/oxygenase were relatively more abundant in the bundle sheath cells of high light than of low light grown plants

  19. Mathematical review of the energy transduction stoichiometries of C4 leaf photosynthesis under limiting light

    NARCIS (Netherlands)

    Yin, X.; Struik, P.C.

    2012-01-01

    A generalized model for electron (e-) transport limited C4 photosynthesis of NAD–malic enzyme and NADP–malic enzyme subtypes is presented. The model is used to review the thylakoid stoichiometries in vivo under strictly limiting light conditions, using published data on photosynthetic quantum yield

  20. Angiosperm n-alkane distribution patterns and the geologic record of C4 grassland evolution

    Science.gov (United States)

    Henderson, A.; Graham, H. V.; Patzkowsky, M.; Fox, D. L.; Freeman, K. H.

    2012-12-01

    n-Alkane average chain-length (ACL) patterns vary regionally with community composition and climate. To clarify the influence of phylogenetic and community patterns, we compiled and analyzed a global database of published n-alkane abundance for n-C27 to C35 homologs in modern plant specimens (n=205). ACL for waxes in C4 non-woody plants are longer than for woody plants, suggesting ACL can serve as an indicator of the three-dimensional structure of local vegetation. Further, these findings suggest compound-specific isotopic data for longer alkane homologs (C31, C33, C35) will proportionately represent non-woody vegetation and isotope measurements of C29 are more representative of woody vegetation. Thus, the combination of ACL and carbon isotope compositions should allow us to disentangle C3 woody, C3 non-woody, and C4 non-woody signals in terrestrial paleorecords. Application of this approach to the geologic record of Miocene C4 grassland expansion in the US Great Plains and the Siwaliks in Pakistan illustrate two very different transition scenarios. Alkane-specific isotopic data indicate C4 grasslands appeared 2.5 Ma in the Great Plains and 6.5 Ma in the Siwaliks, and ACL analysis indicates that this transition involved the replacement of woody vegetation in the US and the replacement of C3 grasses in Pakistan. Our analysis illustrates that, consistent with differences in the timing of C4 grassland, the drivers of change were likely not the same in these regions. Oxygen isotope records suggest that the more recent transition in the Great Plains was associated with climate cooling and possibly changes in disturbance regimes and that the transition in the Siwaliks was likely associated with warming and drying.

  1. Effects of Complement C4 Gene Copy Number Variations, Size Dichotomy, and C4A Deficiency on Genetic Risk and Clinical Presentation of Systemic Lupus Erythematosus in East Asian Populations.

    Science.gov (United States)

    Chen, Ji Yih; Wu, Yee Ling; Mok, Mo Yin; Wu, Yeong-Jian Jan; Lintner, Katherine E; Wang, Chin-Man; Chung, Erwin K; Yang, Yan; Zhou, Bi; Wang, Huanyu; Yu, Dennis; Alhomosh, Alaaedin; Jones, Karla; Spencer, Charles H; Nagaraja, Haikady N; Lau, Yu Lung; Lau, Chak-Sing; Yu, C Yung

    2016-06-01

    Human complement C4 is complex, with multiple layers of diversity. The aims of this study were to elucidate the copy number variations (CNVs) of C4A and C4B in relation to disease risk in systemic lupus erythematosus (SLE), and to compare the basis of race-specific C4A deficiency between East Asians and individuals of European descent. The East Asian study population included 999 SLE patients and 1,347 healthy subjects. Variations in gene copy numbers (GCNs) of total C4, C4A, and C4B, as well as C4-Long and C4-Short genes, were determined and validated using independent genotyping technologies. Genomic regions with C4B96 were investigated to determine the basis of the most basic C4B protein occurring concurrently with C4A deficiency. In East Asians, high GCNs of total C4 and C4A were strongly protective against SLE, whereas low and medium GCNs of total C4 and C4A, and the absence of C4-Short genes, were risk factors for SLE. Homozygous C4A deficiency was infrequent in East Asian subjects, but had an odds ratio (OR) of 12.4 (P = 0.0015) for SLE disease susceptibility. Low serum complement levels were strongly associated with low GCNs of total C4 (OR 3.19, P = 7.3 × 10(-7) ) and C4B (OR 2.53, P = 2.5 × 10(-5) ). Patients with low serum complement levels had high frequencies of anti-double-stranded DNA antibodies (OR 4.96, P = 9.7 × 10(-17) ), hemolytic anemia (OR 3.89, P = 3.6 × 10(-10) ), and renal disease (OR 2.18, P = 8.5 × 10(-6) ). The monomodular-Short haplotype found to be prevalent in European Americans with C4A deficiency, which was in linkage disequilibrium with HLA-DRB1*0301, was scarce in East Asians. Instead, most East Asian subjects with C4A deficiency were found to have a recombinant haplotype with bimodular C4-Long and C4-Short genes, encoding C4B1 and C4B96, which was linked to HLA-DRB1*1501. DNA sequencing revealed an E920K polymorphism in C4B96. C4 CNVs and deficiency of C4A both play an important

  2. The endogenous retroviral insertion in the human complement C4 gene modulates the expression of homologous genes by antisense inhibition.

    Science.gov (United States)

    Schneider, P M; Witzel-Schlömp, K; Rittner, C; Zhang, L

    2001-02-01

    Intron 9 contains the complete endogenous retrovirus HERV-K(C4) as a 6.4-kb insertion in 60% of human C4 genes. The retroviral insertion is in reverse orientation to the C4 coding sequence. Therefore, expression of C4 could lead to the transcription of an antisense RNA, which might protect against exogenous retroviral infections. To test this hypothesis, open reading frames from the HERV sequence were subcloned in sense orientiation into a vector allowing expression of a beta-galactosidase fusion protein. Mouse L cells which had been stably transfected with either the human C4A or C4B gene both carrying the HERV insertion (LC4 cells), and L(Tk-) cells without the C4 gene were transiently transfected either with a retroviral construct or with the wild-type vector. Expression was monitored using an enzymatic assay. We demonstrated that (1) HERV-K(C4) antisense mRNA transcripts are present in cells constitutively expressing C4, (2) expression of retroviral-like constructs is significantly downregulated in cells expressing C4, and (3) this downregulation is further modulated in a dose-dependent fashion following interferon-gamma stimulation of C4 expression. These results support the hypothesis of a genomic antisense strategy mediated by the HERV-K(C4) insertion as a possible defense mechanism against exogenous retroviral infections.

  3. Pathways of primary CO2 fixation in C-4 plants of the family chenopodiaceae from the arid zone of central Asia

    International Nuclear Information System (INIS)

    P'yankov, V.I.; Vakhrusheva, D.V.

    1991-01-01

    The authors determined the kinetics of 14 C incorporation after a 10-sec gulp of 14 CO 2 to study formation of primary photosynthetic products in 35 C-4 species of the family chenopodiaceae in the desert zone of central Asia. Representatives of the main life forms of desert plants with various types of anatomical structure of the assimilating organs (salsoloid, kochioid, atriplercoid, and suaedoid groups) were among the studied species. It was demonstrated that the ratio of pathways of formation of C-4 acids (malate and aspartate) depends upon the structural type affiliation and the ecological conditions of the habitat. Plants of the suaedoid and atriplecoid groups (which usually dwell under conditions of salination) exhibit the aspartate NAD-malic enzyme (NAD-ME) type of C-4 photosynthesis. The malate and aspartate types of metabolism are detected in species of the kochioid group. All biochemical variants (NADP-ME, NAD-ME, and mixed) are represented in the salsoloid group. Psammophilous species of this group have the malate type of acid metabolism, whereas halophilic species have the aspartate type. Quantitative criteria are proposed for referring C-4 plants to the NAD- and NADP-ME types on the basis of formation of primary products. It is demonstrated that the role of the aspartate pathway of CO 2 transfer in plants increases in proportion to worsening of ecological conditions of the habitat. The evolutionary sequence of metabolic systems was formed in the C-3-NAD-ME-NADP-ME direction, the origin of the C-4 syndrome having been associated with colonization of arid territories, especially saline localities

  4. The involvement of HLA-DRBI, DQAI, DQBI and complement C4A Loci in diagnosing systemic lupus erythematosus among Tunisians

    International Nuclear Information System (INIS)

    Ayed, Khaled; Gorgi, Youser; Ayed-Jendoubi, Saloua; Bardi, Rafiqa

    2004-01-01

    Genetic susceptibility to systemetic lupus erythematosus (SLE) varies among populations. Few data exist on associations of HLA class II and class III allels of major histocompatibility complex (MHC) and susceptibility to SLE in Tunisians. We compared HLA-DRBI, DQAI, DQBI and C4 allotypes in 62 Tunisians SLE patients and 100 matched controls. We also assessed the association of specific allels with distinct autoantibody profiles in SLE patients. HLA-DRBI *0301, -DRBI*1501 and C4AQO allels were increased in the SLE patients, while the frequencies of HLA-DRBI*04 and DQBI*03 were decreased. HLA-DQA1*0102 and DQAI*0501 were significantly increased in the SLE patients. HLA-DQBI*0201 and and DQBI*0602 were more frequent in the SLE patients. C4A*QO and C4B*QO were increased in the frequency in the SLE patients compared to the controls, but only C4A null was significantly increased. 11 of 17 SLE patients with the C4 null allele were HLA-DRBI*0301 positive. 3 of the 16 SLE patients with HLA-DRBI*1501 were associated with the HLA-DQBI*0501 rather than DQBI*0602, as has been reported in European SLE patients. The MHC class II allels (DRBI, DQA1, DQB1)and C$ null assosiations noted in other ethnic groups are also found in Tunisians, suggesting shared suspectibility factors across ethnic lines in predisposition to SLE. In contrast to other ethnic groups, MHC class II allels are not associated with the presence of specific autoantibodies in Tunisians SLE patients. (author)

  5. NDVI, C3 and C4 production, and distributions in Great Plains grassland land cover classes

    Science.gov (United States)

    Tieszen, L.L.; Reed, Bradley C.; Bliss, Norman B.; Wylie, Bruce K.; DeJong, Benjamin D.

    1997-01-01

    The distributions of C3 and C4 grasses were used to interpret the distribution, seasonal performance, and potential production of grasslands in the Great Plains of North America. Thirteen major grassland seasonal land cover classes were studied with data from three distinct sources. Normalized Difference Vegetation Index (NDVI) data derived from the National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) sensor were collected for each pixel over a 5-yr period (1989–1993), analyzed for quantitative attributes and seasonal relationships, and then aggregated by land cover class. Data from the State Soil Geographic (STATSGO) database were used to identify dominant plant species contributing to the potential production in each map unit. These species were identified as C3 or C4, and contributions to production were aggregated to provide estimates of the percentage of C3 and C4 production for each intersection of the STATSGO map units and the seasonal land cover classes. Carbon isotope values were obtained at specific sites from the soil organic matter of the upper horizon of soil cores and were related to STATSGO estimates of potential production.The grassland classes were distributed with broad northwest-to-southeast orientations. Some classes had large variations in C3 and C4 composition with high proportions of C4species in the south and low proportions in the north. This diversity of photosynthetic types within land cover classes that cross regions of different temperature and precipitation results in similar seasonal patterns and magnitudes of NDVI. The easternmost class, 65, containing tallgrass prairie components, bluestem, Indiangrass, and switchgrass, possessed the highest maximum NDVI and time-integrated NDVI values each year. Grassland classes varied over 5 yr from a high integrated NDVI mean of 4.9 in class 65 in the east to a low of 1.2 in class 76 (sand sage, blue grama, wheatgrass, and buffalograss) in the

  6. The implantable artificial kidney.

    Science.gov (United States)

    Fissell, William H; Roy, Shuvo

    2009-01-01

    The confluence of an increasing prevalence of end-stage renal disease (ESRD), clinical trial data suggestive of benefit from quotidian dialysis, and ongoing cost/benefit reanalysis of healthcare spending have stimulated interest in technological improvements in provision of ESRD care. For the last decade, our group has focused on enabling technologies that would permit a paradigm shift in dialysis care similar to that brought by implantable defibrillators to arrhythmia management. Two significant barriers to wearable or implantable dialysis persist: package size of the dialyzer and water requirements for preparation of dialysate. Decades of independent research into highly efficient membranes and cell-based bioreactors culminated in a team effort to develop an implantable version of the University of Michigan Renal Assist Device. In this review, the rationale for the design of the implantable artificial kidney is described.

  7. Sorting of C4Olefins with Interpenetrated Hybrid Ultramicroporous Materials by Combining Molecular Recognition and Size-Sieving.

    Science.gov (United States)

    Zhang, Zhaoqiang; Yang, Qiwei; Cui, Xili; Yang, Lifeng; Bao, Zongbi; Ren, Qilong; Xing, Huabin

    2017-12-18

    C 4 olefin separations present one of the great challenges in hydrocarbon purifications owing to their similar structures, thus a single separation mechanism often met with limited success. Herein we report a series of anion-pillared interpenetrated copper coordination for which the cavity and functional site disposition can be varied in 0.2 Å scale increments by altering the anion pillars and organic linkers (GeFSIX-2-Cu-i (ZU-32), NbFSIX-2-Cu-i (ZU-52), GeFSIX-14-Cu-i (ZU-33)), which enable selective recognition of different C 4 olefins. In these materials the rotation of the organic linkers is controlled to create a contracted flexible pore window that enables the size-exclusion of specific C 4 olefins, while still adsorbing significant amounts of 1,3-butadiene (C 4 H 6 ) or 1-butene (n-C 4 H 8 ). Combining the molecular recognition and size-sieving effect, these materials unexpectedly realized the sieving of C 4 H 6 /n-C 4 H 8 , C 4 H 6 /iso-C 4 H 8 , and n-C 4 H 8 /iso-C 4 H 8 with high capacity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Structural Basis for the Function of Complement Component C4 within the Classical and Lectin Pathways of Complement

    DEFF Research Database (Denmark)

    Mortensen, Sofia; Kidmose, Rune Thomas; Petersen, Steen Vang

    2015-01-01

    Complement component C4 is a central protein in the classical and lectin pathways within the complement system. During activation of complement, its major fragment C4b becomes covalently attached to the surface of pathogens and altered self-tissue, where it acts as an opsonin marking the surface...... for removal. Moreover, C4b provides a platform for assembly of the proteolytically active convertases that mediate downstream complement activation by cleavage of C3 and C5. In this article, we present the crystal and solution structures of the 195-kDa C4b. Our results provide the molecular details...... of the rearrangement accompanying C4 cleavage and suggest intramolecular flexibility of C4b. The conformations of C4b and its paralogue C3b are shown to be remarkably conserved, suggesting that the convertases from the classical and alternative pathways are likely to share their overall architecture and mode...

  9. Excitation function of elastic scattering on 12C + 4He system, at low energies

    International Nuclear Information System (INIS)

    Perez-Torres, R.; Aguilera, E. F.; Martinez-Quiroz, E.; Murillo, G.; Belyaeva, T. L.; Maldonado-Velazquez, M.

    2011-01-01

    Interactions in the 12 C + 4 He system are of great interest in astrophysics and to help determine the relative abundances of elements in stars, at the end of helium burning [1, 2]. The Instituto Nacional de Investigaciones Nucleares (ININ) in Mexico, have made measurements of elastic scattering for this system, using the inverse kinematics method with thick white gas [3, 4], for E CM (0.5 - 4 MeV) θ CM = 180 o . In this work we obtain excitation functions of elastic scattering of 12 C + 4 He system with angular and energy dependence; E CM = 0.5 - 4 MeV and θ CM 100 o -170 o .Using inverse kinematics method with thick white gas and energy loss tables. (Author)

  10. Threshold Studies on TNT, Composition B, and C-4 Explosives Using the Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, K S; Switzer, L L; Garcia, F

    2005-09-26

    Steven Impact Tests were performed at low velocity on the explosives TNT, Comp B, and C-4 in attempts to obtain a threshold for reaction. A 76 mm helium driven gas gun was used to accelerate the Steven Test projectiles up to approximately 200 m/s in attempts to react (ignite) the explosive samples. Blast overpressure gauges, acoustic microphones, standard video and high-speed photography were used to characterize the level of any high explosive reaction violence. No bulk reactions were observed in the TNT, Composition B, or C-4 explosive samples impacted up to velocities in the range of 190-200 m/s. This work will outline the experimental details and discuss the lack of reaction when compared to the reaction thresholds of other common explosives.

  11. Separation process of isobutene and 1-butene from spent C4 fraction

    International Nuclear Information System (INIS)

    Araki, M.; Okamura, M.; Deguchi, T.; Higashio, H.

    1987-01-01

    The following is the summary of characteristics of Sumitomo's MTBE process for C 4 separation: 1) High purity isobutylene and 1-butene are economically separated from spent C 4 . 2) No solvents or chemicals are used and little by-product is generated. Therefore, the process is simple and results in relatively low plant capital investment and running cost. 3) No special acid-resistant materials are required for the equipment and facilities of the process. 4) Since reactions in the process are made under mild conditions, no special high temperature or pressure is required. 5) Operation and maintenance work are easy. The process can be operated by a relatively small number of operators

  12. Photosynthetic characteristics of Amaranthus tricolor, a C4 tropical leafy vegetable.

    Science.gov (United States)

    Lin, Z F; Ehleringer, J

    1983-06-01

    The gas exchange characteristics are reported for Amaranthus tricolor, a C4 vegetable amaranth of southeastern Asia. Maximum photosynthetic capacity was 48.3±1.0μmol CO2 m(-2)s(-1) and the temperature optimum was 35°C. The calculated intercellular CO2 concentration at this leaf temperature and an incident photon flux (400-700 mm) of 2 mmol m(-2)s(-1) averaged 208±14 μl l(-1), abnormally high for a C4 species. The photosynthetic rate, intercellular CO2 concentration, and leaf conductance all decreased with an increase in water vapor pressure deficit. However, the decrease in leaf conductance which resulted in a decrease in intercellular CO2 concentration accounted for only one fourth of the observed decrease in photosynthetic rate as water vapor pressure deficit was increased. Subsequent measurements indicated that the depence of net photosynthesis on intercellular CO2 concetration changed with water vapor pressure deficit.

  13. Long-lived transient anion of c-C4F8O

    Science.gov (United States)

    Kočišek, J.; Janečková, R.; Fedor, J.

    2018-02-01

    We report partial cross sections for electron attachment to c-C4F8O, a gas with promising technological applications in free-electron-rich environments. The dissociative electron attachment leads to a number of anionic fragments resulting from complex bond-breaking and bond-forming processes. However, the anion with the highest abundance is the non-dissociated (transient) parent anion which is formed around 0.9 eV electron energy. Its lifetime reaches tens of microseconds. We discuss the origin of this long lifetime, the anion's strong interactions with other molecules, and the consequences for electron-scavenging properties of c-C4F8O in denser environments, in particular for its use in mixtures with CO2 and N2.

  14. Contribution of the Federal Republic of Germany to chapter C.3/C.4

    International Nuclear Information System (INIS)

    1979-03-01

    The paper refers to chapters C.3 and C.4 of the WG 5C report. Different modes of international FBR activities are examined according to the aspects such as ownership, operation, electricity supply, and safeguards. Examples of realization of international FBR development are given. Three aspects are examined as the main potential incentives for internationalization i.e. environment, economics, non-proliferation; some problems are revealed. Aspects of collocation and internationalization in connection with FBRs are investigated based on 3 concepts

  15. Initial events during the evolution of C4 photosynthesis in C3 species of Flaveria.

    Science.gov (United States)

    Sage, Tammy L; Busch, Florian A; Johnson, Daniel C; Friesen, Patrick C; Stinson, Corey R; Stata, Matt; Sultmanis, Stefanie; Rahman, Beshar A; Rawsthorne, Stephen; Sage, Rowan F

    2013-11-01

    The evolution of C4 photosynthesis in many taxa involves the establishment of a two-celled photorespiratory CO2 pump, termed C2 photosynthesis. How C3 species evolved C2 metabolism is critical to understanding the initial phases of C4 plant evolution. To evaluate early events in C4 evolution, we compared leaf anatomy, ultrastructure, and gas-exchange responses of closely related C3 and C2 species of Flaveria, a model genus for C4 evolution. We hypothesized that Flaveria pringlei and Flaveria robusta, two C3 species that are most closely related to the C2 Flaveria species, would show rudimentary characteristics of C2 physiology. Compared with less-related C3 species, bundle sheath (BS) cells of F. pringlei and F. robusta had more mitochondria and chloroplasts, larger mitochondria, and proportionally more of these organelles located along the inner cell periphery. These patterns were similar, although generally less in magnitude, than those observed in the C2 species Flaveria angustifolia and Flaveria sonorensis. In F. pringlei and F. robusta, the CO2 compensation point of photosynthesis was slightly lower than in the less-related C3 species, indicating an increase in photosynthetic efficiency. This could occur because of enhanced refixation of photorespired CO2 by the centripetally positioned organelles in the BS cells. If the phylogenetic positions of F. pringlei and F. robusta reflect ancestral states, these results support a hypothesis that increased numbers of centripetally located organelles initiated a metabolic scavenging of photorespired CO2 within the BS. This could have facilitated the formation of a glycine shuttle between mesophyll and BS cells that characterizes C2 photosynthesis.

  16. Sensitive non-radioactive determination of aminotransferase stereospecificity for C-4' hydrogen transfer on the coenzyme.

    Science.gov (United States)

    Jomrit, Juntratip; Summpunn, Pijug; Meevootisom, Vithaya; Wiyakrutta, Suthep

    2011-02-25

    A sensitive non-radioactive method for determination of the stereospecificity of the C-4' hydrogen transfer on the coenzymes (pyridoxal phosphate, PLP; and pyridoxamine phosphate, PMP) of aminotransferases has been developed. Aminotransferase of unknown stereospecificity in its PLP form was incubated in (2)H(2)O with a substrate amino acid resulted in PMP labeled with deuterium at C-4' in the pro-S or pro-R configuration according to the stereospecificity of the aminotransferase tested. The [4'-(2)H]PMP was isolated from the enzyme protein and divided into two portions. The first portion was incubated in aqueous buffer with apo-aspartate aminotransferase (a reference si-face specific enzyme), and the other was incubated with apo-branched-chain amino acid aminotransferase (a reference re-face specific enzyme) in the presence of a substrate 2-oxo acid. The (2)H at C-4' is retained with the PLP if the aminotransferase in question transfers C-4' hydrogen on the opposite face of the coenzyme compared with the reference aminotransferase, but the (2)H is removed if the test and reference aminotransferases catalyze hydrogen transfer on the same face. PLP formed in the final reactions was analyzed by LC-MS/MS for the presence or absence of (2)H. The method was highly sensitive that for the aminotransferase with ca. 50 kDa subunit molecular weight, only 2mg of the enzyme was sufficient for the whole test. With this method, the use of radioactive substances could be avoided without compromising the sensitivity of the assay. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Valence band photoemission from in-situ grown GaAs(100)-c(4 x 4)

    Czech Academy of Sciences Publication Activity Database

    Jiříček, Petr; Cukr, Miroslav; Bartoš, Igor; Adell, M.; Strasser, T.; Schattke, W.

    2006-01-01

    Roč. 56, č. 1 (2006), s. 21-26 ISSN 0011-4626. [Symposium on Surface Physics /10./. Praha, 11.07.2005-15.07.2005] R&D Projects: GA ČR(CZ) GA202/04/0994 Institutional research plan: CEZ:AV0Z10100521 Keywords : GaAs(100)-c(4X4) * surface states * band structure * structure plot Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.568, year: 2006

  18. What is the behavior of a C4 quadriplegic mouth calligrapher constant function of?

    Directory of Open Access Journals (Sweden)

    Nonaka Tetsushi

    2011-12-01

    Full Text Available Motor coordination of a professional C4 quadriplegic calligrapher who trained himself to use his mouth to write with brush and ink by gripping a brush between his teeth was reported. Through the analysis of movement during calligraphy, it was found that the movement variability of the head-neck system was exploited to stabilize certain relations between the brush and the paper surface (e.g., brush pressure.

  19. What is the behavior of a C4 quadriplegic mouth calligrapher constant function of?

    OpenAIRE

    Nonaka Tetsushi

    2011-01-01

    Motor coordination of a professional C4 quadriplegic calligrapher who trained himself to use his mouth to write with brush and ink by gripping a brush between his teeth was reported. Through the analysis of movement during calligraphy, it was found that the movement variability of the head-neck system was exploited to stabilize certain relations between the brush and the paper surface (e.g., brush pressure).

  20. Polygonumnolides C1-C4; minor dianthrone glycosides from the roots of Polygonum multiflorum Thunb.

    Science.gov (United States)

    Yang, Jian-Bo; Li, Li; Dai, Zhong; Wu, Yu; Geng, Xing-Chao; Li, Bo; Ma, Shuang-Cheng; Wang, Ai-Guo; Su, Ya-Lun

    2016-09-01

    Four new dianthrone glycosides, named polygonumnolides C1-C4 (1-4), were isolated from the dried roots of Polygonum multiflorum Thunb, together with two known emodin dianthrones (5-6). Their hepatotoxicities were evaluated against L-02 cell lines. Compounds 1-4 showed weak hepatotoxicity against L-02 cell lines with IC50 values of 313.05, 205.20, 294.20, and 207.35 μM, respectively.

  1. Long-lived transient anion of c-C4F8O

    Czech Academy of Sciences Publication Activity Database

    Kočišek, Jaroslav; Janečková, R.; Fedor, Juraj

    2018-01-01

    Roč. 148, č. 7 (2018), č. článku 074303. ISSN 0021-9606 R&D Projects: GA ČR GA17-04844S Institutional support: RVO:61388955 Keywords : negative-ion * electron-attachment * chemistry * c4f8o * lifetimes * gases Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 2.965, year: 2016

  2. Using multiple collaborative agents for adaptive Quality of Service management of C4ISR networks

    OpenAIRE

    Rivera, Raymond A.

    2001-01-01

    This research explores the potential of agent technology for adaptive Quality of Service (QoS) management of C4ISR networks. With the growing emphasis on information superiority, any time savings or additional utilization of resources enabled by effective network management becomes increasingly important. Intelligent agents are ideal for assessing information, adapting to dynamic conditions, and predicting future network conditions. In the kernel of the proposed multiple agent system (MAS) te...

  3. Clinical and pathological correlations of C4d immunostaining and its infl uence on the outcome of kidney transplant recipients

    Directory of Open Access Journals (Sweden)

    Virna Nowotny Carpio

    2011-09-01

    Full Text Available INTRODUCTION: C4d is a marker of antibody-mediated rejection (ABMR in kidney allografts, although cellular rejection also have C4d deposits. OBJECTIVE: To correlate C4d expression with clinico-pathological parameters and graft outcomes at three years. METHODS: One hundred forty six renal transplantation recipients with graft biopsies by indication were included. C4d staining was performed by paraffin-immunohistochemistry. Graft function and survival were measured, and predictive variables of the outcome were determined by multivariate Cox regression. RESULTS: C4d staining was detected in 48 (31% biopsies, of which 23 (14.7% had diffuse and 25 (16% focal distribution. Pre-transplantation panel reactive antibodies (%PRA class I and II were significantly higher in C4d positive patients as compared to those C4d negative. Both glomerulitis and pericapillaritis were associated to C4d (p = 0.002 and p < 0.001, respectively. The presence of C4d in biopsies diagnosed as no rejection (NR, acute cellular rejection (ACR or interstitial fibrosis/ tubular atrophy (IF/TA did not impact graft function or survival. Compared to NR, ACR and IF/TA C4d-, patients with ABMR C4d+ had the worst graft survival over 3 years (p = 0.034, but there was no difference between ABMR versus NR, ACR and IF/TA that were C4d positive (p = 0.10. In Cox regression, graft function at biopsy and high %PRA levels were predictors of graft loss. CONCLUSIONS: This study confirmed that C4d staining in kidney graft biopsies is a clinically useful marker of ABMR, with well defined clinical and pathological correlations. The impact of C4d deposition in other histologic diagnoses deserves further investigation.

  4. C4BPAL1, a member of the human regulator of complement activation (RCA) gene cluster that resulted from the duplication of the gene coding for the [alpha]-chain of C4b-binding protein

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Corral, P.; Pardo-Manuel de Villena, F.; Rey-Campos, J.; Rodriguez de Cordoba, S. (Unidad de Immunologia, Madrid (Spain))

    1993-07-01

    The regulator of complement activation (RCA) gene cluster evolved by multiple gene duplications to produce a family of genes coding for proteins that collectively control the activation of the complement system. The authors report here the characterization of C4BPAL1, a member of the human RCA gene cluster that arose from the duplication of the C4BPA gene after the separation of rodent and primate lineages. C4BPAL1 maps 20 kb downstream of the C4BPA gene and is in the same 5[prime] to 3[prime] orientation found for all RCA genes characterized thus far. It includes nine exon-like regions homologous to exons 2-8, 11, and 12 of the C4BPA gene. Analysis of the C4BPAL1 sequence suggests that it is currently a pseudogene in humans. However, comparisons between C4BPAL1 and the human and murine C4BPA genes show sequence conservation, which strongly suggests that, for a long period of time, C4BPAL1 has been a functional gene coding for a protein with structural requirements similar to those of the [alpha]-chain of C4b-binding protein. 50 refs., 5 figs., 1 tab.

  5. Laboratory detection of the C3N an C4H free radicals

    Science.gov (United States)

    Gottlieb, C. A.; Gottlieb, E. W.; Thaddeus, P.; Kawamura, H.

    1983-01-01

    The millimeter-wave spectra of the linear carbon chain free radicals C3N and C4H, first identified in IRC + 10216 and hitherto observed only in a few astronomical sources, have been detected with a Zeeman-modulated spectrometer in laboratory glow discharges through low pressure flowing mixtures of N2 + HC3N and He + HCCH, respectively. Four successive rotational transitions between 168 and 198 GHz have been measured for C3N, and five rotational transitions between 143 and 200 GHz for C4H; each is a well-resolved spin doublet owing to the unpaired electron present in both species. Precise values for the rotational, centrifugal distortion, and spin doubling constants have been obtained, which, with hyperfine constants derived from observations of the lower rotational transitions in the astronomical source TMC 1, allow all the rotational transitions of C3N and C4H at frequencies less than 300 GHz to be calculated to an absolute accuracy exceeding 1 ppm.

  6. Implementation of Data Mining to Analyze Drug Cases Using C4.5 Decision Tree

    Science.gov (United States)

    Wahyuni, Sri

    2018-03-01

    Data mining was the process of finding useful information from a large set of databases. One of the existing techniques in data mining was classification. The method used was decision tree method and algorithm used was C4.5 algorithm. The decision tree method was a method that transformed a very large fact into a decision tree which was presenting the rules. Decision tree method was useful for exploring data, as well as finding a hidden relationship between a number of potential input variables with a target variable. The decision tree of the C4.5 algorithm was constructed with several stages including the selection of attributes as roots, created a branch for each value and divided the case into the branch. These stages would be repeated for each branch until all the cases on the branch had the same class. From the solution of the decision tree there would be some rules of a case. In this case the researcher classified the data of prisoners at Labuhan Deli prison to know the factors of detainees committing criminal acts of drugs. By applying this C4.5 algorithm, then the knowledge was obtained as information to minimize the criminal acts of drugs. From the findings of the research, it was found that the most influential factor of the detainee committed the criminal act of drugs was from the address variable.

  7. C4 grasses prosper as carbon dioxide eliminates desiccation in warmed semi-arid grassland.

    Science.gov (United States)

    Morgan, Jack A; LeCain, Daniel R; Pendall, Elise; Blumenthal, Dana M; Kimball, Bruce A; Carrillo, Yolima; Williams, David G; Heisler-White, Jana; Dijkstra, Feike A; West, Mark

    2011-08-03

    Global warming is predicted to induce desiccation in many world regions through increases in evaporative demand. Rising CO(2) may counter that trend by improving plant water-use efficiency. However, it is not clear how important this CO(2)-enhanced water use efficiency might be in offsetting warming-induced desiccation because higher CO(2) also leads to higher plant biomass, and therefore greater transpirational surface. Furthermore, although warming is predicted to favour warm-season, C(4) grasses, rising CO(2) should favour C(3), or cool-season plants. Here we show in a semi-arid grassland that elevated CO(2) can completely reverse the desiccating effects of moderate warming. Although enrichment of air to 600 p.p.m.v. CO(2) increased soil water content (SWC), 1.5/3.0 °C day/night warming resulted in desiccation, such that combined CO(2) enrichment and warming had no effect on SWC relative to control plots. As predicted, elevated CO(2) favoured C(3) grasses and enhanced stand productivity, whereas warming favoured C(4) grasses. Combined warming and CO(2) enrichment stimulated above-ground growth of C(4) grasses in 2 of 3 years when soil moisture most limited plant productivity. The results indicate that in a warmer, CO(2)-enriched world, both SWC and productivity in semi-arid grasslands may be higher than previously expected.

  8. PCA based feature reduction to improve the accuracy of decision tree c4.5 classification

    Science.gov (United States)

    Nasution, M. Z. F.; Sitompul, O. S.; Ramli, M.

    2018-03-01

    Splitting attribute is a major process in Decision Tree C4.5 classification. However, this process does not give a significant impact on the establishment of the decision tree in terms of removing irrelevant features. It is a major problem in decision tree classification process called over-fitting resulting from noisy data and irrelevant features. In turns, over-fitting creates misclassification and data imbalance. Many algorithms have been proposed to overcome misclassification and overfitting on classifications Decision Tree C4.5. Feature reduction is one of important issues in classification model which is intended to remove irrelevant data in order to improve accuracy. The feature reduction framework is used to simplify high dimensional data to low dimensional data with non-correlated attributes. In this research, we proposed a framework for selecting relevant and non-correlated feature subsets. We consider principal component analysis (PCA) for feature reduction to perform non-correlated feature selection and Decision Tree C4.5 algorithm for the classification. From the experiments conducted using available data sets from UCI Cervical cancer data set repository with 858 instances and 36 attributes, we evaluated the performance of our framework based on accuracy, specificity and precision. Experimental results show that our proposed framework is robust to enhance classification accuracy with 90.70% accuracy rates.

  9. Modelling metabolic evolution on phenotypic fitness landscapes: a case study on C4 photosynthesis.

    Science.gov (United States)

    Heckmann, David

    2015-12-01

    How did the complex metabolic systems we observe today evolve through adaptive evolution? The fitness landscape is the theoretical framework to answer this question. Since experimental data on natural fitness landscapes is scarce, computational models are a valuable tool to predict landscape topologies and evolutionary trajectories. Careful assumptions about the genetic and phenotypic features of the system under study can simplify the design of such models significantly. The analysis of C4 photosynthesis evolution provides an example for accurate predictions based on the phenotypic fitness landscape of a complex metabolic trait. The C4 pathway evolved multiple times from the ancestral C3 pathway and models predict a smooth 'Mount Fuji' landscape accordingly. The modelled phenotypic landscape implies evolutionary trajectories that agree with data on modern intermediate species, indicating that evolution can be predicted based on the phenotypic fitness landscape. Future directions will have to include structural changes of metabolic fitness landscape structure with changing environments. This will not only answer important evolutionary questions about reversibility of metabolic traits, but also suggest strategies to increase crop yields by engineering the C4 pathway into C3 plants. © 2015 Authors; published by Portland Press Limited.

  10. The superfamily of C3b/C4b-binding proteins

    DEFF Research Database (Denmark)

    Kristensen, Torsten; D'Eustachio, P; Ogata, R T

    1987-01-01

    The determination of primary structures by amino acid and nucleotide sequencing for the C3b-and/or C4b-binding proteins H, C4BP, CR1, B, and C2 has revealed the presence of a common structural element. This element is approximately 60 amino acids long and is repeated in a tandem fashion, commencing...... at the amino-terminal end of each molecule. Two other complement components, C1r and C1s, have two of these repeating units in the carboxy-terminal region of their noncatalytic A chains. Three noncomplement proteins, beta 2-glycoprotein I (beta 2I), the interleukin 2 receptor (IL 2 receptor), and the b chain...... of factor XIII, have 4, 2 and 10 of these repeating units, respectively. These proteins obviously belong to the above family, although there is no evidence that they interact with C3b and/or C4b. Human haptoglobin and rat leukocyte common antigen also contain two and three repeating units, respectively...

  11. Capacity for C4 photosynthesis among relatively advanced species of Flaveria

    International Nuclear Information System (INIS)

    Moore, B.D.; Ku, M.S.B.; Edwards, G.E.

    1987-01-01

    Leaves of 5 summer-grown Flaveria species, all thought to be C 4 plants, were exposed to 14 CO 2 for 3-16 s. Analysis of 14 C-products and extrapolation of labelling curves to zero time allowed estimation of the percentage of CO 2 incorporated via the C 4 cycle. This value was about 90% in F. vaginata and F. palmeri, 95% in F. australasica, 97% in F. bidentis, and 100% in F. trinervia. Localization of leaf carboxylases and decarboxylase was examined after purifying mesophyll and bundle sheath protoplasts by a simplified procedure. All species except F. trinervia showed some enrichment of RuBisCO to NADP-malic enzyme in mesophyll preparations. Mesophyll RuBisCO activities (up to 50 μmol/mg Chl x h) constituted ≤7% of the total leaf RuBisCO (corrected for Chl distribution). Incomplete compartmentation of NADP-malic enzyme of direct entry of CO 2 into the bundle sheath may also occur in F. vaginata and F. palmeri. The data indicate that at least these 2 species (along with F. brownii from previous results) should be classified as less advanced, C 4 -like species

  12. LDH-C4: a target with therapeutic potential for cancer and contraception.

    Science.gov (United States)

    Gupta, G S

    2012-12-01

    The lactate dehydrogenase (LDH) has been studied widely because it exists in various isozymic forms. The association of A and B subunits of LDH can generate five tetrameric isozymes, but the finding of the sixth isozyme in mature human testis and sperm indicated the presence of an additional subunit of LDH, designated as LDH-X (also termed LDH-C4 due to tetrameric nature of C-subunit). LDH-C4 isozyme is an iso-, allo-, and auto-antigen present in mammalian sperm cells. The synthesis of LDH-C4 in the testis takes place during sexual maturation, and it is the predominant fraction in mature spermatozoa. Though, originally considered to be testis specific, LDH-C or Ldh3 in mice was later detected in the murine oocyte and early embryo. Ldh3 in mouse supports its role in energy production in spermatids that favor lactate as substrate and in spermatozoa with a characteristic aerobic glycolytic path to yield ATP. During last two decades, cancer/testis-associated genes (CTAs) which are expressed only in the germinal epithelium of the testis are also expressed in some cancer cells, but not in non-cancerous somatic tissues. The CTAs are considered promising candidates for diagnosis and immunotherapy of cancer. The sperm-specific Ldh-c gene has been shown to express in a broad spectrum of human tumors, with high frequency in lung cancer, melanoma, and breast cancer; the protein being expressed virtually in all tumor types tested. Accordingly, LDH-C4 is the unique target for contraception in both males and females and offers potential future for immunotherapy of different types of cancers. As LDH-C has a preference for lactate as a substrate, LDH-C activation in cancer may depend on lactate for ATP production. The major aim of this article is to review the salient features of LDH-C subunit and the immune responses of LDH-C4 in homologous and heterologous species in relation to its role in acceptance or rejection of the allograft and its application in contraception and

  13. Artificial Intelligence in Astronomy

    Science.gov (United States)

    Devinney, E. J.; Prša, A.; Guinan, E. F.; Degeorge, M.

    2010-12-01

    From the perspective (and bias) as Eclipsing Binary researchers, we give a brief overview of the development of Artificial Intelligence (AI) applications, describe major application areas of AI in astronomy, and illustrate the power of an AI approach in an application developed under the EBAI (Eclipsing Binaries via Artificial Intelligence) project, which employs Artificial Neural Network technology for estimating light curve solution parameters of eclipsing binary systems.

  14. Quo Vadis, Artificial Intelligence?

    OpenAIRE

    Berrar, Daniel; Sato, Naoyuki; Schuster, Alfons

    2010-01-01

    Since its conception in the mid 1950s, artificial intelligence with its great ambition to understand and emulate intelligence in natural and artificial environments alike is now a truly multidisciplinary field that reaches out and is inspired by a great diversity of other fields. Rapid advances in research and technology in various fields have created environments into which artificial intelligence could embed itself naturally and comfortably. Neuroscience with its desire to understand nervou...

  15. Artificial cognition architectures

    CERN Document Server

    Crowder, James A; Friess, Shelli A

    2013-01-01

    The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

  16. An artificial muscle computer

    Science.gov (United States)

    Marc O'Brien, Benjamin; Alexander Anderson, Iain

    2013-03-01

    We have built an artificial muscle computer based on Wolfram's "2, 3" Turing machine architecture, the simplest known universal Turing machine. Our computer uses artificial muscles for its instruction set, output buffers, and memory write and addressing mechanisms. The computer is very slow and large (0.15 Hz, ˜1 m3); however by using only 13 artificial muscle relays, it is capable of solving any computable problem given sufficient memory, time, and reliability. The development of this computer shows that artificial muscles can think—paving the way for soft robots with reflexes like those seen in nature.

  17. Independent and Parallel Evolution of New Genes by Gene Duplication in Two Origins of C4 Photosynthesis Provides New Insight into the Mechanism of Phloem Loading in C4 Species.

    Science.gov (United States)

    Emms, David M; Covshoff, Sarah; Hibberd, Julian M; Kelly, Steven

    2016-07-01

    C4 photosynthesis is considered one of the most remarkable examples of evolutionary convergence in eukaryotes. However, it is unknown whether the evolution of C4 photosynthesis required the evolution of new genes. Genome-wide gene-tree species-tree reconciliation of seven monocot species that span two origins of C4 photosynthesis revealed that there was significant parallelism in the duplication and retention of genes coincident with the evolution of C4 photosynthesis in these lineages. Specifically, 21 orthologous genes were duplicated and retained independently in parallel at both C4 origins. Analysis of this gene cohort revealed that the set of parallel duplicated and retained genes is enriched for genes that are preferentially expressed in bundle sheath cells, the cell type in which photosynthesis was activated during C4 evolution. Furthermore, functional analysis of the cohort of parallel duplicated genes identified SWEET-13 as a potential key transporter in the evolution of C4 photosynthesis in grasses, and provides new insight into the mechanism of phloem loading in these C4 species. C4 photosynthesis, gene duplication, gene families, parallel evolution. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  18. Artificial life and life artificialization in Tron

    Directory of Open Access Journals (Sweden)

    Carolina Dantas Figueiredo

    2012-12-01

    Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

  19. Appearance and accumulation of C4 carbon pathway enzymes in developing wheat leaves

    International Nuclear Information System (INIS)

    Aoyagi, K.; Bassham, J.A.

    1986-01-01

    Soluble protein has been extracted from sections of wheat leaves, from base to tip, and the content of several key enzymes of photosynthetic carbon assimilation in each section has been determined by the protein blot method. In the first leaf, ribulose 1,5-bisphosphate carboxylase (RuBPC) (EC 4.1.1.39) in the basal 0 to 1 centimeter section is about 12% the level in the tip section, whereas phosphoenolpyruvate carboxylase (EC 4.1.1.31) is present in small amounts in the basal section and does not change much in the tip. Pyruvate orthophosphate dikinase (PPDK) (EC 2.7.9.1) first appears in the 4 to 6 centimeter section and increases gradually with development to 10-fold in the tip. Malic enzyme, NADP-dependent (EC 1.3.1.37) also appears in the 4 to 6 centimeter section but remains low to the tip. Fixation of 14 CO 2 by wheat leaf base sections resulted in 42% of total incorporation into malate and aspartate, indicating β-carboxylation, whereas in the tip section these labeled compounds were only 8% of the total. Although the amount of PPDK in wheat leaves is only 1 to 3% of that in maize leaves, this C 3 PPDK may have a limited role in photosynthesis leading to formation of C 4 compounds. The possibility of a further role, similar to that in C 4 plants, but for intracellular carbon transport in wheat leaves is discussed. The presence of malic dehydrogenase, NADP-specific (EC 1.1.1.82) in wheat leaf chloroplasts was shown, a necessary though not sufficient condition for such a proposed role. Assuming each of the four enzymes associated with C 4 carbon transport were fully active in vivo during photosynthesis, PPDK would still be rate limiting, even in the leaf tip where its activity is maximal. Possible evolutionary and breeding implications are discussed

  20. The roles of phosphorylation and SHAGGY-like protein kinases in geminivirus C4 protein induced hyperplasia.

    Directory of Open Access Journals (Sweden)

    Katherine Mills-Lujan

    Full Text Available Even though plant cells are highly plastic, plants only develop hyperplasia under very specific abiotic and biotic stresses, such as when exposed to pathogens like Beet curly top virus (BCTV. The C4 protein of BCTV is sufficient to induce hyperplasia and alter Arabidopsis development. It was previously shown that C4 interacts with two Arabidopsis Shaggy-like protein kinases, AtSK21 and 23, which are negative regulators of brassinosteroid (BR hormone signaling. Here we show that the C4 protein interacts with five additional AtSK family members. Bikinin, a competitive inhibitor of the seven AtSK family members that interact with C4, induced hyperplasia similar to that induced by the C4 protein. The Ser49 residue of C4 was found to be critical for C4 function, since: 1 mutagenesis of Ser49 to Ala abolished the C4-induced phenotype, abolished C4/AtSK interactions, and resulted in a mutant protein that failed to induce changes in the BR signaling pathway; 2 Ser49 is phosphorylated in planta; and 3 plant-encoded AtSKs must be catalytically active to interact with C4. A C4 N-myristoylation site mutant that does not localize to the plasma membrane and does not induce a phenotype, retained the ability to bind AtSKs. Taken together, these results suggest that plasma membrane associated C4 interacts with and co-opts multiple AtSKs to promote its own phosphorylation and activation to subsequently compromise cell cycle control.

  1. Crystal structure of a four-stranded intercalated DNA: d(C4)

    Science.gov (United States)

    Chen, L.; Cai, L.; Zhang, X.; Rich, A.

    1994-01-01

    The crystal structure of d(C4) solved at 2.3-A resolution reveals a four-stranded molecule composed of two interdigitated or intercalated duplexes. The duplexes are held together by hemiprotonated cytosine-cytosine base pairs and are parallel stranded, but the two duplexes point in opposite directions. The molecule has a slow right-handed twist of 12.4 degrees between covalently linked cytosine base pairs, and the base stacking distance is 3.1 A. This is in general agreement with the NMR studies. A biological role for DNA in this conformation is suggested.

  2. Electron transfer patterns of the di-heme protein cytochrome c(4) from Pseudomonas stutzeri

    DEFF Research Database (Denmark)

    Raffalt, Anders Christer; Schmidt, L.; Christensen, Hans Erik Mølager

    2009-01-01

    We report kinetic data for the two-step electron transfer (ET) oxidation and reduction of the two-domain di-heme redox protein Pseudomonas stutzeri cytochrome (cyt) c(4) by [Co(bipy)(3)](2- 3-) (bipy = 2,2'-bipyridine). Following earlier reports, the data accord with both bi- and tri......) for which fast, ms to sub-ms intramolecular interheme ET is a crucial step. The rate constant dependence on the solvent viscosity has disclosed strong coupling to both a (set of) frictionally damped solvent/protein nuclear modes and intramolecular friction-less "ballistic" modes, indicative of notable...

  3. An unusual cause of chest pain: Fused cervical vertebra (C3-C4

    Directory of Open Access Journals (Sweden)

    Daipayan Chatterjee

    2014-01-01

    Full Text Available Cervicogenic angina is paroxysmal precordialgia usually due to lower cervical vertebral involvement. But upper cervical vertebral segmental anomaly causing cervicogenic angina is rare. Herein, we report a case of cervicogenic angina due to fused 3 rd and 4 th cervical vertebra in a 37-year female, which was initially misdiagnosed as angina and treated likewise. But, persistence of symptoms led to evaluation of her cervical spine and subsequent diagnosis. Cervical traction, physiotherapy and posture training relieved her of her symptoms with no recurrence till 6 months of follow-up. Fused C3-C4 can be a cause of precordialgia and physicians should be aware of it.

  4. A dynamic hydro-mechanical and biochemical model of stomatal conductance for C4 photosynthesis

    OpenAIRE

    Bellasio, C.; Quirk, J.; Buckley, T.N.; Beerling, D.J.

    2017-01-01

    C4 plants are major grain (maize, sorghum), sugar (sugarcane) and biofuel (Miscanthus) producers,\\ud and contribute ~20% to global productivity. Plants lose water through stomatal pores in order to\\ud acquire CO2 (assimilation, A), and control their carbon-for-water balance by regulating stomatal\\ud conductance (gS). The ability to mechanistically predict gS and A in response to atmospheric CO2,\\ud water availability and time is critical for simulating stomatal control of plant-atmospheric ca...

  5. Direct Measurement of 12C+4He Fusion Cross Section Near Stellar energy

    International Nuclear Information System (INIS)

    Sagara, K.; Fujita, K.; Teranishi, T.; Taniguchi, M.; Oba, N.; Yamaguchi, H.; Matsuda, S.

    2011-01-01

    The reaction 12 C+ 4 He → 16 O+γ at E cm = 0.3 MeV plays an important role in stellar evolution, but the reaction cross section has not been measured yet. Recently we succeeded to measure total cross section of the reaction down to E cm = 1.5 MeV at Kyushu University. We have a plan to measure the cross section down to 0.7 MeV in several years, and to extrapolate the results to 0.3 MeV. (author)

  6. Crystal structure features in a new compound C4B25Mg1.42

    Science.gov (United States)

    Konovalikhin, S. V.; Ponomarev, V. I.

    2015-09-01

    The composition of C4B25Mg1.42 crystal obtained by self-propagating high-temperature synthesis was determined using X-ray diffraction. This is the first crystalline structure where all boron atoms in the В12 icosahedron occupy crystallographically independent positions; this circumstance allowed us to analyze the effect of substituents on bond lengths in the icosahedron. The crystal structure features, including the channels filled with disordered Mg atoms and the spread of В—В endo- and exo-bond lengths in the icosahedra, are described. A crystallochemical analysis of pair bonds has been performed for the first time.

  7. Selective Hydrogenation of Concentrated Vinyl Acetylene Mixed C4 by Modified Pd Catalysts: Effect of Cu

    Directory of Open Access Journals (Sweden)

    Paisan Insorn

    2016-12-01

    Full Text Available The Pd and Pd-Cu on alumina catalysts were tested for hydrogenation of vinyl acetylene in mixed C4 in a circulating tubular reactor. The results showed that adding proper amounts of Cu improved the reaction activity, but inhibited 1,3-butadiene selectivity. Moreover, the presence of Cu retarded the carbon deposition on catalysts during the reaction. Temperature programmed oxidation (TPO, Temperature programmed reduction (TPR, H2 chemisorption, and X-ray photoelectron spectroscopy (XPS were utilized to characterize the catalysts. The characterization suggested both geometric and electronic modifications.

  8. Integrating autonomous distributed control into a human-centric C4ISR environment

    Science.gov (United States)

    Straub, Jeremy

    2017-05-01

    This paper considers incorporating autonomy into human-centric Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) environments. Specifically, it focuses on identifying ways that current autonomy technologies can augment human control and the challenges presented by additive autonomy. Three approaches to this challenge are considered, stemming from prior work in two converging areas. In the first, the problem is approached as augmenting what humans currently do with automation. In the alternate approach, the problem is approached as treating humans as actors within a cyber-physical system-of-systems (stemming from robotic distributed computing). A third approach, combines elements of both of the aforementioned.

  9. Artificial insemination in poultry

    Science.gov (United States)

    Artificial insemination is a relative simple yet powerful tool geneticists can employ for the propagation of economically important traits in livestock and poultry. In this chapter, we address the fundamental methods of the artificial insemination of poultry, including semen collection, semen evalu...

  10. Photorespiratory properties of protoplasts from C3-C4intermediate species of moricandia

    International Nuclear Information System (INIS)

    Holbrook, G.P.; Chollet, Raymond

    1986-01-01

    Protoplasts were isolated from leaves of the C 3 -C 4 intermediate species, Moricandia arvensis (L.) DC. and Moricandia spinosa Pomel. Analysis by light and transmission electron microscopy indicated that these purified preparations contained both mesophyll protoplasts (MP) and bundle-sheath protoplasts (BSP). Conventional density gradient centrifugation procedures failed to yield separations of pure protoplasts from each cell-type. With these heterogeneous suspensions of MP and BSP, values measured for (i) the percentage inhibition of photosynthetic CO 2 fixation by O 2 , (ii) the apparent K (CO 2 ) of photosynthesis, and (iii) dark/light ratios of the rate of 14 CO 2 evolution during decarboxylation of exogenous [1- 14 C]glycine were not significantly different from those determined for protoplasts preparations from related or representative C 3 plants, including M. foetida, Nicotiana tavacum, and Triticum aestivum. In contrast, previous comparisons with C 3 species, using intact leaf tissue from M, arvensis, have shown a reduced sensitivity of new photosynethic to inhibition by O 2 [Holaday et al., Plant Sci. Lett., 27 (1982) 181] and an enhanced capacity for the photosynthetic refixation of CO 2 evolved during decarboxylation of exogenous photorespiratory substrates [Holbrook et al., Plant Physiol., 77 (1985) 578]. We conclude that these photosynthetic properties, associated with reduced photorespiration by M. arvensis and M. spinosa, are dependent upon the integrity of the anatomical and ultrastructural arrangement of bundle-sheath and mesophyll cells in these C 3 -C 4 intermediate species. (author)

  11. High altitude C(4) grasslands in the northern Andes: relicts from glacial conditions?

    Science.gov (United States)

    Boom, A; Mora, G; Cleef, A M.; Hooghiemstra, H

    2001-06-01

    The altitudinal vegetation distribution in the northern Andes during glacial time differed from the present-day conditions as a result of temperature and precipitation change. New evidence indicate that as a response to a reduced atmospheric partial CO(2) pressure (pCO(2)), the competitive balance between C(3) and C(4) plants have changed. Effects may have remained virtually undetected in pollen records, but can be observed using a stable carbon isotope analysis. Vegetation dominated by C(4) taxa, belonging to the families Cyperaceae (e.g. Bulbostylis and Cyperus) and Poaceae (e.g. Muhlenbergia, Paspalum and Sporobolus), may have been able to replace for a significant part the modern type C(3) taxa (e.g. species belonging to Carex, Rhynchospora, Aciachne, Agrostis, Calamagrostis, and Chusquea). Impact of reduced glacial atmospheric pCO(2) levels and lower glacial temperatures on the composition and the elevational distribution of the vegetation types is discussed. The present high Andean vegetation communities may differ from the glacial equivalents (non-modern analogue situation). We identified dry Sporobolus lasiophyllus tussock grassland and Arcytophyllum nitidum dwarfshrub paramo as the possible relict communities from glacial time. The effect on previous estimates of paleo-temperatures is estimated to be small.

  12. Recent Progress on C-4-Modified Podophyllotoxin Analogs as Potent Antitumor Agents

    Science.gov (United States)

    Liu, Ying-Qian; Tian, Jing; Qian, Keduo; Zhao, Xiao-Bo; Morris-Natschke, Susan L.; Yang, Liu; Nan, Xiang; Tian, Xuan; Lee, Kuo-Hsiung

    2015-01-01

    Podophyllotoxin (PPT), as well as its congeners and derivatives, exhibits pronounced biological activities, especially antineoplastic effects. Its strong inhibitory effect on tumor cell growth led to the development of three of the most highly prescribed anticancer drugs in the world, etoposide, teniposide, and the water-soluble prodrug etoposide phosphate. Their clinical success as well as intriguing mechanism of action stimulated great interest in further modification of PPT for better antitumor activity. The C-4 position has been a major target for structural derivatization aimed at either producing more potent compounds or overcoming drug resistance. Accordingly, numerous PPT derivatives have been prepared via hemisynthesis and important structure–activity relationship (SAR) correlations have been identified. Several resulting compounds, including GL-331, TOP-53, and NK611, reached clinical trials. Some excellent reviews on the distribution, sources, applications, synthesis, and SAR of PPT have been published. This review focuses on a second generation of new etoposide-related drugs and provides detailed coverage of the current status and recent development of C-4-modified PPT analogs as anticancer clinical trial candidates. PMID:24827545

  13. Prediksi Ketepatan Waktu Kelulusan Dengan Algoritma Data Mining C4.5

    Directory of Open Access Journals (Sweden)

    Indah Puji Astuti

    2017-11-01

    Full Text Available The student is one of entities in University or Higher Education. The student has a variety of data, such as self-identity information such as address, type of school, work of parents, type of class, etc. In fact many students whose graduation rate is different, on time and not on time. The number of students who graduate is not on time will be a problem not only for university but also for faculty. The number of students graduating each year is one of points of assessment when faculty or study program submits accreditation. C4.5 Algorithm is one of classification algorithm with decision trees. In this study conducted an analysis of student data Engineering Studies Program University of Muhammadiyah Ponorogo 2012/2013. The decision trees in this case is useful for exploring student data, finding the hidden relationship between a number of candidate input attributes with a target attribute. The input attribute consist of, the type of school, address, work of parent, and type of class. The output attribute to classify is status, which consists of "on time" and "not on time". The results from this analysis shown that in this case the C4.5 algorithm can predict with an accuracy value only 82%.

  14. Can miscanthus C4 photosynthesis compete with festulolium C3 photosynthesis in a temperate climate?

    DEFF Research Database (Denmark)

    Jiao, Xiurong; Kørup, Kirsten; Andersen, Mathias Neumann

    2017-01-01

    Miscanthus, a perennial grass with C4 photosynthesis, is regarded as a promising energy crop due to its high biomass productivity. Compared with other C4 species, most miscanthus genotypes have high cold tolerances at 14 °C. However, in temperate climates, temperatures below 14 °C are common....../10 °C, 10/8 °C and 6/4 °C) conditions in a controlled environment. Measurements of photosynthetic light response curves, operating quantum yield of photosystem II (ΦPSII), net photosynthetic rate at a PAR of 1000 μmol m−2 s−1 (A1000) and dark-adapted chlorophyll fluorescence (Fv/Fm) were made at each....../8 °C and 6/4 °C than of miscanthus genotypes. This indicates that festulolium may be more productive than the currently investigated miscanthus genotypes in cool, maritime climates. Within miscanthus, only one M. sacchariflorus genotype exhibited the same photosynthetic capacity as Hornum at both cold...

  15. THRESHOLD STUDIES ON TNT, COMPOSITION B, C-4, AND ANFO EXPLOSIVES USING THE STEVEN IMPACT TEST

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, K S; Switzer, L L; Garcia, F

    2006-06-20

    Steven Impact Tests were performed at low velocity on the explosives TNT (trinitrotolulene), Composition B (63% RDX, 36% TNT, and 1% wax by weight), C-4 (91% RDX, 5.3% Di (2-ethylhexyl) sebacate, 2.1% Polyisobutylene, and 1.6% motor oil by weight) and ANFO (94% ammonium Nitrate with 6% Fuel Oil) in attempts to obtain a threshold for reaction. A 76 mm helium driven gas gun was used to accelerate the Steven Test projectiles up to approximately 200 m/s in attempts to react (ignite) the explosive samples. Blast overpressure gauges, acoustic microphones, standard video and high-speed photography were used to characterize the level of any high explosive reaction violence. No bulk reactions were observed in the TNT, Composition B, C-4 or ANFO explosive samples impacted up to velocities in the range of 190-200 m/s. This work will outline the experimental details and discuss the lack of reaction when compared to the reaction thresholds of other common explosives. These results will also be compared to that of the Susan Test and reaction thresholds observed in the common small-scale safety tests such as the drop hammer and friction tests in hopes of drawing a correlation.

  16. ARL participation in the C4ISR OTM experiment: integration and performance results

    Science.gov (United States)

    Zong, Lei; O'Brien, Barry J.

    2007-04-01

    The Command, Control, Communication, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) On-The- Move (OTM) demonstration is an annual showcase of how innovative technologies can help modern troops increase their situational awareness (SA) in battlefield environments. To evaluate the effectiveness these new technologies have on the soldiers' abilities to gather situational information, the demonstration involves United States Army National Guard troops in realistic war game scenarios at an Army Reserve training ground. The Army Research Laboratory (ARL) was invited to participate in the event, with the objective demonstrating system-level integration of disparate technologies developed for gathering SA information in small unit combat operations. ARL provided expertise in Unattended Ground Sensing (UGS) technology, Unmanned Ground Vehicle (UGV) technology, information processing and wireless mobile ad hoc communication. The ARL C4ISR system included a system of multimodal sensors (MMS), a trip wire imager, a man-portable robotic vehicle (PackBot), and low power sensor radios for communication between an ARL system and a hosting platoon vehicle. This paper will focus on the integration effort of bringing the multiple families of sensor assets together into a working system.

  17. Functional recruitment of the human complement inhibitor C4BP to Yersinia pseudotuberculosis outer membrane protein Ail.

    Science.gov (United States)

    Ho, Derek K; Riva, Rauna; Kirjavainen, Vesa; Jarva, Hanna; Ginström, Erica; Blom, Anna M; Skurnik, Mikael; Meri, Seppo

    2012-05-01

    Ail is a 17-kDa chromosomally encoded outer membrane protein that mediates serum resistance (complement resistance) in the pathogenic Yersiniae (Yersinia pestis, Y. enterocolitica, and Y. pseudotuberculosis). In this article, we demonstrate that Y. pseudotuberculosis Ail from strains PB1, 2812/79, and YPIII/pIB1 (serotypes O:1a, O:1b, and O:3, respectively) can bind the inhibitor of the classical and lectin pathways of complement, C4b-binding protein (C4BP). Binding was observed irrespective of serotype tested and independently of YadA, which is the primary C4BP receptor of Y. enterocolitica. Disruption of the ail gene in Y. pseudotuberculosis resulted in loss of C4BP binding. Cofactor assays revealed that bound C4BP is functional, because bound C4BP in the presence of factor I cleaved C4b. In the absence of YadA, Ail conferred serum resistance to strains PB1 and YPIII, whereas serum resistance was observed in strain 2812/79 in the absence of both YadA and Ail, suggesting additional serum resistance factors. Ail from strain YPIII/pIB1 alone can mediate serum resistance and C4BP binding, because its expression in a serum-sensitive laboratory strain of Escherichia coli conferred both of these phenotypes. Using a panel of C4BP mutants, each deficient in a single complement control protein domain, we observed that complement control protein domains 6-8 are important for binding to Ail. Binding of C4BP was unaffected by increasing heparin or salt concentrations, suggesting primarily nonionic interactions. These results indicate that Y. pseudotuberculosis Ail recruits C4BP in a functional manner, facilitating resistance to attack from complement.

  18. Synthesis and Cytotoxicity Evaluation of C4‐ and C5‐Modified Analogues of the α,β‐Unsaturated Lactone of Pironetin

    Science.gov (United States)

    Huang, David S.; Wong, Henry L.

    2017-01-01

    Abstract Pironetin is a natural product with potent antiproliferative activity that forms a covalent adduct with α‐tubulin via conjugate addition into the natural product's α,β‐unsaturated lactone. Although pironetin's α,β‐unsaturated lactone is involved in its binding to tubulin, the structure–activity relationship at different positions of the lactone have not been thoroughly evaluated. For a systematic evaluation of the structure–activity relationships at the C4 and C5 positions of the α,β‐unsaturated lactone of pironetin, twelve analogues of the natural product were prepared by total synthesis. Modifying the stereochemistry at the C4 and/or C5 positions of the α,β‐unsaturated lactone of pironetin resulted in loss of antiproliferative activity in OVCAR5 ovarian cancer cells. While changing the C4 ethyl substituent with groups such as methyl, propyl, cyclopropyl, and isobutyl were tolerated, groups with larger steric properties such as an isopropyl and benzyl groups were not. PMID:28261964

  19. Synthesis and Cytotoxicity Evaluation of C4- and C5-Modified Analogues of the α,β-Unsaturated Lactone of Pironetin.

    Science.gov (United States)

    Huang, David S; Wong, Henry L; Georg, Gunda I

    2017-04-06

    Pironetin is a natural product with potent antiproliferative activity that forms a covalent adduct with α-tubulin via conjugate addition into the natural product's α,β-unsaturated lactone. Although pironetin's α,β-unsaturated lactone is involved in its binding to tubulin, the structure-activity relationship at different positions of the lactone have not been thoroughly evaluated. For a systematic evaluation of the structure-activity relationships at the C4 and C5 positions of the α,β-unsaturated lactone of pironetin, twelve analogues of the natural product were prepared by total synthesis. Modifying the stereochemistry at the C4 and/or C5 positions of the α,β-unsaturated lactone of pironetin resulted in loss of antiproliferative activity in OVCAR5 ovarian cancer cells. While changing the C4 ethyl substituent with groups such as methyl, propyl, cyclopropyl, and isobutyl were tolerated, groups with larger steric properties such as an isopropyl and benzyl groups were not. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  20. Effects of L-carnitine and Pentoxifylline on the Activity of Lactate Dehydrogenase C4 isozyme and Motility of Testicular Spermatozoa in Mice.

    Science.gov (United States)

    Aliabadi, Elham; Karimi, Fatemeh; Rasti, Mozhgan; Akmali, Masoumeh; Esmaeilpour, Tahereh

    2013-04-01

    Extracted sperm from the testis have poor motility. Moreover, their motility changes during their journey through epidydimis. Meanwhile, they face high concentration of L-carnitin. In addition, lactate dehydrogenase C4 (LDH-C4) gene disorders has been shown to cause impaired sperm motility, leading to infertility in male mice. The aim of this study was to evaluate sperm motility and LDH-C4 enzyme activity upon L-carnitine (LC) and Pentoxifylline (PTX) administrations in mice. We extracted testicular sperm of 48 mice and divided them into three equal parts. One part was incubated with Ham's F10 medium (control), the other parts were treated with Ham's F10 containing LC and PTX with a final concentration of 1.76 mM, for 30 min at room temperature. Sperm motility was assessed according to the World Health Organization (WHO) criteria. Sperm LDH-C4 enzyme activity was measured by spectrophotometery method. Statistical analyses were performed using ANOVA and Fisher's LSD test, and a p-value less than 0.05 was considered as a statistically significant difference. Sperm motility increased after 30 min of incubation in LC- and PTX-treated group (p<0.001). LC and PTX administrations showed a significant increase in the LDHC4 enzyme activity of sperm compared to that of the controls after 30 min (P=0.04 and 0.01, respectively). The effects of LC and PTX on motility of sperm can be explained by an increase in LDH-C4 enzyme activity that may influence male fertility status. We suggest that LC as a non-toxic antioxidant is more suitable for use in assisted reproductive technique protocols than PTX.

  1. Artificial intelligence in medicine.

    Science.gov (United States)

    Ramesh, A N; Kambhampati, C; Monson, J R T; Drew, P J

    2004-09-01

    Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of different artificial intelligent techniques is presented in this paper along with the review of important clinical applications. The proficiency of artificial intelligent techniques has been explored in almost every field of medicine. Artificial neural network was the most commonly used analytical tool whilst other artificial intelligent techniques such as fuzzy expert systems, evolutionary computation and hybrid intelligent systems have all been used in different clinical settings. Artificial intelligence techniques have the potential to be applied in almost every field of medicine. There is need for further clinical trials which are appropriately designed before these emergent techniques find application in the real clinical setting.

  2. Artificial intelligence in medicine.

    Science.gov (United States)

    Ramesh, A. N.; Kambhampati, C.; Monson, J. R. T.; Drew, P. J.

    2004-01-01

    INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of different artificial intelligent techniques is presented in this paper along with the review of important clinical applications. RESULTS: The proficiency of artificial intelligent techniques has been explored in almost every field of medicine. Artificial neural network was the most commonly used analytical tool whilst other artificial intelligent techniques such as fuzzy expert systems, evolutionary computation and hybrid intelligent systems have all been used in different clinical settings. DISCUSSION: Artificial intelligence techniques have the potential to be applied in almost every field of medicine. There is need for further clinical trials which are appropriately designed before these emergent techniques find application in the real clinical setting. PMID:15333167

  3. Quo Vadis, Artificial Intelligence?

    Directory of Open Access Journals (Sweden)

    Daniel Berrar

    2010-01-01

    Full Text Available Since its conception in the mid 1950s, artificial intelligence with its great ambition to understand and emulate intelligence in natural and artificial environments alike is now a truly multidisciplinary field that reaches out and is inspired by a great diversity of other fields. Rapid advances in research and technology in various fields have created environments into which artificial intelligence could embed itself naturally and comfortably. Neuroscience with its desire to understand nervous systems of biological organisms and systems biology with its longing to comprehend, holistically, the multitude of complex interactions in biological systems are two such fields. They target ideals artificial intelligence has dreamt about for a long time including the computer simulation of an entire biological brain or the creation of new life forms from manipulations of cellular and genetic information in the laboratory. The scope for artificial intelligence in neuroscience and systems biology is extremely wide. This article investigates the standing of artificial intelligence in relation to neuroscience and systems biology and provides an outlook at new and exciting challenges for artificial intelligence in these fields. These challenges include, but are not necessarily limited to, the ability to learn from other projects and to be inventive, to understand the potential and exploit novel computing paradigms and environments, to specify and adhere to stringent standards and robust statistical frameworks, to be integrative, and to embrace openness principles.

  4. Can the progressive increase of C4 bundle sheath leakiness at low PFD be explained by incomplete suppression of photorespiration?

    NARCIS (Netherlands)

    Kromdijk, J.; Griffiths, H.; Schepers, H.E.

    2010-01-01

    The ability to concentrate CO2 around Rubisco allows C-4 crops to suppress photorespiration. However, as phosphoenolpyruvate regeneration requires ATP, the energetic efficiency of the C-4 pathway at low photosynthetic flux densities (PFD) becomes a balancing act between primary fixation and

  5. The differences between NAD-ME and NADP-ME subtypes of C4 photosynthesis: more than decarboxylating enzymes

    Directory of Open Access Journals (Sweden)

    Xiaolan Rao

    2016-10-01

    Full Text Available As an adaptation to changing climatic conditions that caused high rates of photorespiration, C4 plants have evolved to display higher photosynthetic efficiency than C3 plants under elevated temperature, high light intensities and drought. The C4 plants independently evolved more than 60 times in 19 families of angiosperms to establish similar but not uniform C4 mechanisms to concentrate CO2 around the carboxylating enzyme Rubisco. C4 photosynthesis is divided into at least two basic biochemical subtypes based on the primary decarboxylating enzymes, NAD-dependent malic enzyme (NAD-ME and NADP-dependent malic enzyme (NADP-ME. The multiple polygenetic origins of these subtypes raise questions about the association of C4 variation between biochemical subtypes and diverse lineages. This review addresses the differences in evolutionary scenario, leaf anatomy, and especially C4 metabolic flow, C4 transporters and cell-specific function deduced from recently reported cell-specific transcriptomic, proteomic and metabolic analyses of NAD-ME and NADP-ME subtypes. Current omic analysis has revealed the extent to which component abundances differ between the two biochemical subtypes, leading to a better understanding of C4 photosynthetic mechanisms in NAD-ME and NADP-ME subtypes.

  6. Complement system proteins which interact with C3b or C4b A superfamily of structurally related proteins

    DEFF Research Database (Denmark)

    Reid, K B M; Bentley, D R; Campbell, R D

    1986-01-01

    Recent cDNA sequencing data has allowed the prediction of the entire amino acid sequences of complement components factor B and C2, the complement control proteins factor H and C4b-binding protein and a partial sequence for the Cab/C4b receptor CR1. These proteins all contain internal repeating...

  7. C4.4A gene ablation is compatible with normal epidermal development and causes modest overt phenotypes

    DEFF Research Database (Denmark)

    Kriegbaum, Mette Camilla; Jacobsen, Benedikte; Fuchtbauer, Annette

    2016-01-01

    C4.4A is a modular glycolipid-anchored Ly6/uPAR/alpha-neurotoxin multidomain protein that exhibits a prominent membrane-associated expression in stratified squamous epithelia. C4.4A is also expressed in various solid cancer lesions, where high expression levels often are correlated to poor...

  8. Metabolic flux ratio analysis and cell staining suggest the existence of C4 photosynthesis in Phaeodactylum tricornutum.

    Science.gov (United States)

    Huang, A; Liu, L; Zhao, P; Yang, C; Wang, G C

    2016-03-01

    Mechanisms for carbon fixation via photosynthesis in the diatom Phaeodactylum tricornutum Bohlin were studied recently but there remains a long-standing debate concerning the occurrence of C4 photosynthesis in this species. A thorough investigation of carbon metabolism and the evidence for C4 photosynthesis based on organelle partitioning was needed. In this study, we identified the flux ratios between C3 and C4 compounds in P. tricornutum using (13)C-labelling metabolic flux ratio analysis, and stained cells with various cell-permeant fluorescent probes to investigate the likely organelle partitioning required for single-cell C4 photosynthesis. Metabolic flux ratio analysis indicated the C3/C4 exchange ratios were high. Cell staining indicated organelle partitioning required for single-cell C4 photosynthesis might exist in P. tricornutum. The results of (13)C-labelling metabolic flux ratio analysis and cell staining suggest single-cell C4 photosynthesis exists in P. tricornutum. This study provides insights into photosynthesis patterns of P. tricornutum and the evidence for C4 photosynthesis based on (13)C-labelling metabolic flux ratio analysis and organelle partitioning. © 2015 The Society for Applied Microbiology.

  9. Elements Required for an Efficient NADP-Malic Enzyme Type C4 Photosynthesis1[C][W][OPEN

    Science.gov (United States)

    Wang, Yu; Long, Stephen P.; Zhu, Xin-Guang

    2014-01-01

    C4 photosynthesis has higher light, nitrogen, and water use efficiencies than C3 photosynthesis. Although the basic anatomical, cellular, and biochemical features of C4 photosynthesis are well understood, the quantitative significance of each element of C4 photosynthesis to the high photosynthetic efficiency are not well defined. Here, we addressed this question by developing and using a systems model of C4 photosynthesis, which includes not only the Calvin-Benson cycle, starch synthesis, sucrose synthesis, C4 shuttle, and CO2 leakage, but also photorespiration and metabolite transport between the bundle sheath cells and mesophyll cells. The model effectively simulated the CO2 uptake rates, and the changes of metabolite concentrations under varied CO2 and light levels. Analyses show that triose phosphate transport and CO2 leakage can help maintain a high photosynthetic rate by balancing ATP and NADPH amounts in bundle sheath cells and mesophyll cells. Finally, we used the model to define the optimal enzyme properties and a blueprint for C4 engineering. As such, this model provides a theoretical framework for guiding C4 engineering and studying C4 photosynthesis in general. PMID:24521879

  10. Synergistic inhibition of the intrinsic factor X activation by protein S and C4b-binding protein

    NARCIS (Netherlands)

    Koppelman, S. J.; van't Veer, C.; Sixma, J. J.; Bouma, B. N.

    1995-01-01

    The complement protein C4b-binding protein plays an important role in the regulation of the protein C anticoagulant pathway. C4b-binding protein can bind to protein S, thereby inhibiting the cofactor activity of protein S for activated protein C. In this report, we describe a new role for

  11. Expression of C4.4A in an in Vitro Human Tissue-Engineered Skin Model

    DEFF Research Database (Denmark)

    Jacobsen, Benedikte; Larouche, Danielle; Rochette-Drouin, Olivier

    2017-01-01

    , the biological function of C4.4A remains unknown. To enable further studies, we evaluated the expression of C4.4A in monolayer cultures of normal human keratinocytes and in tissue-engineered skin substitutes (TESs) produced by the self-assembly approach, which allow the formation of a fully differentiated...

  12. Universal Properties of the C4 Magnetic Phase in Hole Doped Ternary Superconducting Pnictides

    Science.gov (United States)

    Chmaissem, Omar

    A Fe2As2 (A =Alkali Earth) superconductors exhibit phase diagrams that are remarkably similar when substitutions are made at any of the available crystallographic sites. In recent work, we demonstrated that some hole-doped compositions with low temperature orthorhombic structures exhibit universal phase reentrance back to the tetragonal symmetry with the formation of a previously unknown magnetic C4 phase facilitated by the recovery of magnetic degeneracy coupled with spin reorientation from the in-plane to the out-of-plane c-axis direction. Using neutron diffraction and Mossbauer spectroscopy, we unraveled the nature of this new phase as being a rare double-Q magnetic structure in which two orthogonal spin density waves combine to produce the tetragonal magnetic symmetry with a checkerboard -like Fe sublattice in which half the sites are magnetic (magnetic moment nearly doubled) while the other half are not. Our results give strong evidence for the electronic itineracy of the system and provide a definite proof that the structural and magnetic transitions are driven by magnetic fluctuations rather than other mechanisms. The exact location and shape of the C4 phase space have somewhat remained until recently a mystery as the phase shifted together with the superconducting dome to different doping levels in various phase diagrams but with no any clear trends. Noting the complete absence of this phase in any known electron or isovalent-substituted analog, it has become clear that detailed mapping of the phase properties requires hole-doped systems that go beyond the customary binary diagrams. In this talk, I will present and discuss the properties of a two dimensional map in a broad range of compositions that extend between binary end-members of elaborate ternary phase diagrams. This work establishes the universality of the C4 phase, its robustness and provides a quantitative relationship between the magnetic properties and the A-site ionic size and internal

  13. An intraoral self-contained artificial larynx.

    Science.gov (United States)

    Lowry, L D; Katz, P A; Brenman, H S; Schwartz, H L

    1982-01-01

    It has been estimated that approximately one third to one half of persons undergoing total laryngectomy do not obtain a satisfactory voice. These patients remain aphonic or use artificial larynges to facilitate their communication. A multidisciplinary group at Thomas Jefferson University has developed a miniaturized artificial larynx that fits on a dental prosthesis or dental plate which has over a 100-dB sound pressure level output at the source and is powered by two hearing aid batteries with a life expectancy of over 100 hours of continuous use. Clinical trials have shown that persons using other artificial devices quickly adapt to this new artificial larynx, and the first person who began using the device, an Italian, commented that he could now use both hands; and felt that this was a great help because of his ethnic background.

  14. Expression of C4.4A in precursor lesions of pulmonary adenocarcinoma and squamous cell carcinoma

    DEFF Research Database (Denmark)

    Jacobsen, Benedikte; Santoni-Rugiu, Eric; Illemann, Martin

    2012-01-01

    in precursor lesions of lung squamous cell carcinoma and adenocarcinoma was investigated by stainings with a specific anti-C4.4A antibody. In the transformation from normal bronchial epithelium to squamous cell carcinoma, C4.4A was weakly expressed in basal cell hyperplasia but dramatically increased...... in squamous metaplasia. This was confined to the cell membrane and sustained in dysplasia, carcinoma in situ, and the invasive carcinoma. The induction of C4.4A already at the stage of hyperplasia could indicate that it is a marker of very early squamous differentiation, which aligns well with our earlier...... finding that C4.4A expression levels do not provide prognostic information on the survival of squamous cell carcinoma patients. In the progression from normal alveolar epithelium to peripheral adenocarcinoma, we observed an unexpected, distinct cytoplasmic staining for C4.4A in a fraction of atypical...

  15. A novel pharmacologic action of glucocorticosteroids on leukotriene C4 catabolism.

    Science.gov (United States)

    Zaitsu, M; Hamasaki, Y; Aoki, Y; Miyazaki, S

    2001-07-01

    Leukotriene (LT) C(4), a potent chemical mediator in human bronchial asthma, is metabolized to less active LTE(4) via LTD(4) in 2 consecutive enzymatic reactions by gamma-glutamyl transpeptidases and dipeptidases. We examined whether this inactivation process of LTC(4) was affected by fluticasone propionate, beclomethasone dipropionate, disodium cromoglycate, and salbutamol sulfate in transformed human bronchial epithelial cells. Fluticasone propionate and beclomethasone dipropionate accelerated LTC(4) catabolism by inducing activity of a LTC(4)-degrading enzyme, gamma-glutamyl transpeptidase-related enzyme (gamma-GTPRE), in transformed human bronchial epithelial cells. The activation of gamma-GTPRE might be regulated transcriptionally. This is a novel regulatory mechanism by which glucocorticosteroids exert antiasthma activities.

  16. Numerical Calculation of Coherent Synchrotron Radiation Effects Using TraFiC4

    International Nuclear Information System (INIS)

    Kabel, Andreas C.

    2000-01-01

    Coherent synchrotron radiation (CSR) occurs when short bunches travel on strongly bent trajectories. Its effects on high-quality beams can be severe and are well understood qualitatively. For quantitative results, however, one has to rely on numerical methods. There exist several simulation codes utilizing different approaches. The authors describe in some detail the code TraFiC 4 developed at DESY for design and analysis purposes, which approaches the problem from first principles and solves the equations of motion either perturbatively or self-consistently. They present some calculational results and comparison with experimental data. Also, they give examples of how the code can be used to design beamlines with minimal emittance growth due to CSR

  17. Promotor polymorphisms in leukotriene C4 synthase and risk of ischemic cerebrovascular disease

    DEFF Research Database (Denmark)

    Freiberg, J.J.; Tybjaerg-Hansen, A.; Sillesen, H.

    2008-01-01

    OBJECTIVE: Cysteinyl leukotrienes are involved in inflammation and possibly in early carotid atherosclerosis. We tested the hypothesis that the -444 A/C and -1072 G/A polymorphisms of the leukotriene C(4) synthase associate with risk of ischemic cerebrovascular disease. METHODS AND RESULTS: We...... genotyped 10 592 individuals from the Danish general population, the Copenhagen City Heart Study. During 24 years of follow-up, 557 individuals developed ischemic cerebrovascular disease. The allele frequency was 0.07 for -1072 A and 0.29 for -444 C. Cumulative incidence for ischemic cerebrovascular disease...... was higher for -1072 AA versus GG genotype (log-rank: P=0.002), and lower for -444 CC versus AA genotype (log-rank: P=0.008). Combined genotypes showed corresponding cumulative incidence differences (log-rank: P=0.003). Multifactorially adjusted hazard ratios for ischemic cerebrovascular disease were 2...

  18. Optical spectroscopy study of c(4 x 2) Ge (001)-surfaces, covered with atomic Au wires

    Energy Technology Data Exchange (ETDEWEB)

    Bass, Utz; Meyer, Sebastian; Schaefer, Joerg; Geurts, Jean [Universitaet Wuerzburg, Physikalisches Institut, Am Hubland, 97074 Wuerzburg (Germany); Speiser, Eugen; Esser, Norbert [ISAS, Albert-Einstein-Strasse 9, 12489 Berlin (Germany)

    2011-07-01

    Novel quasi-1D systems like e.g. atomic gold chains on a c(4x2) reconstructed Ge(001)-surfaces enable the investigation of 1D-effects like the possible occurrence of the Luttinger- to Fermi liquid transition. As there is a crucial interplay of the lattice vibrations and the electrical and structural properties on such sensitive systems, phonon dynamics are in the focus of this work. The phonons were addressed by Raman spectroscopy and reveal a clear change from the Ge-oxide layer to the final surface with Au-nano wires. Thermally deoxidizing the Ge-surface under UHV leads to a distinct low-frequency vibration around 65cm-1. Its frequency range and its persistence after Gold deposition in the submonolayer range indicate that this signal is surface related. Additionally, the surface-induced anisotropy of the optical reflectance was complementary investigated by Reflectance-Anisotropy-Spectroscopy (RAS) and IR-ellipsometry.

  19. Improved tissue culture conditions for the emerging C4model Panicum hallii.

    Science.gov (United States)

    Grant, Joshua N; Burris, Jason N; Stewart, C Neal; Lenaghan, Scott C

    2017-04-27

    Panicum hallii Vasey (Hall's panicgrass) is a compact, perennial C 4 grass in the family Poaceae, which has potential to enable bioenergy research for switchgrass (Panicum virgatum L.). Unlike P. hallii, switchgrass has a large genome, allopolyploidy, self-incompatibility, a long life cycle, and large stature-all suboptimal traits for rapid genetics research. Herein we improved tissue culture methodologies for two inbred P. hallii populations: FIL2 and HAL2, to enable further development of P. hallii as a model C 4 plant. The optimal seed-derived callus induction medium was determined to be Murashige and Skoog (MS) medium supplemented with 40 mg L -1 L-cysteine, 300 mg L -1 L-proline, 3% sucrose, 1 g L -1 casein hydrolysate, 3 mg L -1 2,4-dichlorophenoxyacetic acid (2,4-D), and 45 μg L -1 6-benzylaminopurine (BAP), which resulted in callus induction of 51 ± 29% for FIL2 and 81 ± 19% for HAL2. The optimal inflorescence-derived callus induction was observed on MP medium (MS medium supplemented with 2 g L -1 L-proline, 3% maltose, 5 mg L -1 2,4-D, and 500 μg L -1 BAP), resulting in callus induction of 100 ± 0.0% for FIL2 and 84 ± 2.4% for HAL2. Shoot regeneration rates of 11.5 ± 0.8 shoots/gram for FIL2 and 11.3 ± 0.6 shoots/gram for HAL2 were achieved using seed-induced callus, whereas shoot regeneration rates of 26.2 ± 2.6 shoots/gram for FIL2 and 29.3 ± 3.6 shoots/gram for HAL2 were achieved from inflorescence-induced callus. Further, cell suspension cultures of P. hallii were established from seed-derived callus, providing faster generation of callus tissue compared with culture using solidified media (1.41-fold increase for FIL2 and 3.00-fold increase for HAL2). Aside from abbreviated tissue culture times from callus induction to plant regeneration for HAL2, we noted no apparent differences between FIL2 and HAL2 populations in tissue culture performance. For both populations, the cell suspension cultures

  20. Yersinia enterocolitica serum resistance proteins YadA and ail bind the complement regulator C4b-binding protein.

    Science.gov (United States)

    Kirjavainen, Vesa; Jarva, Hanna; Biedzka-Sarek, Marta; Blom, Anna M; Skurnik, Mikael; Meri, Seppo

    2008-08-29

    Many pathogens are equipped with factors providing resistance against the bactericidal action of complement. Yersinia enterocolitica, a Gram-negative enteric pathogen with invasive properties, efficiently resists the deleterious action of human complement. The major Y. enterocolitica serum resistance determinants include outer membrane proteins YadA and Ail. Lipopolysaccharide (LPS) O-antigen (O-ag) and outer core (OC) do not contribute directly to complement resistance. The aim of this study was to analyze a possible mechanism whereby Y. enterocolitica could inhibit the antibody-mediated classical pathway of complement activation. We show that Y. enterocolitica serotypes O:3, O:8, and O:9 bind C4b-binding protein (C4bp), an inhibitor of both the classical and lectin pathways of complement. To identify the C4bp receptors on Y. enterocolitica serotype O:3 surface, a set of mutants expressing YadA, Ail, O-ag, and OC in different combinations was tested for the ability to bind C4bp. The studies showed that both YadA and Ail acted as C4bp receptors. Ail-mediated C4bp binding, however, was blocked by the O-ag and OC, and could be observed only with mutants lacking these LPS structures. C4bp bound to Y. enterocolitica was functionally active and participated in the factor I-mediated degradation of C4b. These findings show that Y. enterocolitica uses two proteins, YadA and Ail, to bind C4bp. Binding of C4bp could help Y. enterocolitica to evade complement-mediated clearance in the human host.

  1. Yersinia enterocolitica serum resistance proteins YadA and ail bind the complement regulator C4b-binding protein.

    Directory of Open Access Journals (Sweden)

    Vesa Kirjavainen

    Full Text Available Many pathogens are equipped with factors providing resistance against the bactericidal action of complement. Yersinia enterocolitica, a Gram-negative enteric pathogen with invasive properties, efficiently resists the deleterious action of human complement. The major Y. enterocolitica serum resistance determinants include outer membrane proteins YadA and Ail. Lipopolysaccharide (LPS O-antigen (O-ag and outer core (OC do not contribute directly to complement resistance. The aim of this study was to analyze a possible mechanism whereby Y. enterocolitica could inhibit the antibody-mediated classical pathway of complement activation. We show that Y. enterocolitica serotypes O:3, O:8, and O:9 bind C4b-binding protein (C4bp, an inhibitor of both the classical and lectin pathways of complement. To identify the C4bp receptors on Y. enterocolitica serotype O:3 surface, a set of mutants expressing YadA, Ail, O-ag, and OC in different combinations was tested for the ability to bind C4bp. The studies showed that both YadA and Ail acted as C4bp receptors. Ail-mediated C4bp binding, however, was blocked by the O-ag and OC, and could be observed only with mutants lacking these LPS structures. C4bp bound to Y. enterocolitica was functionally active and participated in the factor I-mediated degradation of C4b. These findings show that Y. enterocolitica uses two proteins, YadA and Ail, to bind C4bp. Binding of C4bp could help Y. enterocolitica to evade complement-mediated clearance in the human host.

  2. Intelligence: Real or artificial?

    Science.gov (United States)

    Schlinger, Henry D.

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally referred to behavior-environment relations and not to inferred internal structures and processes. It is concluded that if workers in artificial intelligence are to succeed in their general goal, then they must design machines that are adaptive, that is, that can learn. Thus, artificial intelligence researchers must discard their essentialist model of natural intelligence and adopt a selectionist model instead. Such a strategic change should lead them to the science of behavior analysis. PMID:22477051

  3. Involvement of C4 allotypes in the pathogenesis of human diseases O envolvimento dos alótipos de C4 na patogênese das doenças humanas

    Directory of Open Access Journals (Sweden)

    Eliana Sueco Tibana Samano

    2004-01-01

    Full Text Available The complement system is an important humoral defense mechanism that plays a relevant role against microbial agents, inflammatory response control, and immunocomplex clearance. Classical complement pathway activation is antibody-dependent. The C4 component participates in the initial step of activation, and C4 expression is determined by 2 pairs of allotypes: C4A and C4B. Deficiencies in C4 allotypes have been associated with several diseases. The aim of the present review is evaluate the reported data in the literature regarding specific C4A and C4B deficiencies and characterize their clinical relevance. We searched the MEDLINE and LILACS databases. Papers referring to total C4 deficiency without allotype evaluation and case reports of primary C4 deficiency were not included. Deficiencies in C4 allotypes have been associated with Mycobacterium leprae infection, erythema nodosum, systemic sclerosis with anti-topoisomerase I antibodies, intermediate congenital adrenal hyperplasia with DR5 genotype, diabetes mellitus type 1 with DR3,4 genotype, and diabetes mellitus with antibodies against islet cells. C4 allotype deficiency is also related to C4B deficiency and autoimmune-associated diseases, such as systemic lupus erythematosus, or diseases with an autoimmune component, such as autism. Some reports associate C4A with thyroiditis after delivery as well as limited and systemic sclerosis without anti-topoisomerase I antibodies. However, the studies with C4A and C4B have been concentrated in isolated populations, and some of the studies could not be reproduced by other authors.O sistema complemento constitui um importante sistema de defesa humoral, exercendo papel relevante na resposta contra agentes microbianos, no controle da resposta inflamatória e na depuração de imunocomplexos. A ativação da via clássica é dependente da formação do complexo antígeno-anticorpo. O componente C4 do complemento participa da etapa inicial de ativa

  4. Principles of artificial intelligence

    CERN Document Server

    Nilsson, Nils J

    1980-01-01

    A classic introduction to artificial intelligence intended to bridge the gap between theory and practice, Principles of Artificial Intelligence describes fundamental AI ideas that underlie applications such as natural language processing, automatic programming, robotics, machine vision, automatic theorem proving, and intelligent data retrieval. Rather than focusing on the subject matter of the applications, the book is organized around general computational concepts involving the kinds of data structures used, the types of operations performed on the data structures, and the properties of th

  5. Artificial intelligence in cardiology

    OpenAIRE

    Bonderman, Diana

    2017-01-01

    Summary Decision-making is complex in modern medicine and should ideally be based on available data, structured knowledge and proper interpretation in the context of an individual patient. Automated algorithms, also termed artificial intelligence that are able to extract meaningful patterns from data collections and build decisions upon identified patterns may be useful assistants in clinical decision-making processes. In this article, artificial intelligence-based studies in clinical cardiol...

  6. Artificial intelligence in medicine.

    OpenAIRE

    Ramesh, A. N.; Kambhampati, C.; Monson, J. R. T.; Drew, P. J.

    2004-01-01

    INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of ...

  7. Intelligence: Real or artificial?

    OpenAIRE

    Schlinger, Henry D.

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally r...

  8. Wear resistance of a modified polymethyl methacrylate artificial tooth compared to five commercially available artificial tooth materials.

    Science.gov (United States)

    Kamonwanon, Pranithida; Yodmongkol, Sirasa; Chantarachindawong, Rojcharin; Thaweeboon, Sroisiri; Thaweeboon, Boonyanit; Srikhirin, Toemsak

    2015-08-01

    Wear resistance is a limitation of artificial denture teeth. Improving the wear resistance of conventional artificial denture teeth is of value to prosthodontic patients. The purpose of this in vitro study was to evaluate the wear resistance and hardness of modified polymethyl methacrylate artificial denture teeth compared to 5 commercially available artificial tooth materials. This study evaluated 180 artificial denture teeth (6 groups) that included 3 groups of conventional artificial teeth (MajorDent, Cosmo HXL, and Gnathostar), 2 groups of composite resin artificial teeth (Endura and SR Orthosit PE), and 1 group of modified surface artificial teeth. The flattened buccal surface of each tooth (n=15) was prepared for investigation with the Vickers hardness test and the elucidate wear test (n=15) by using a brushing machine. Each group was loaded for 18,000 cycles, at 2 N, and 150 rpm. The wear value was identified with a profilometer. The data were statistically analyzed by using 1-way ANOVA and post hoc Turkey honestly significant difference tests (α=.001). The tribologies were observed under a scanning electron microscope, and the cytotoxicities were evaluated by MTT assay. The Vickers hardnesses ranged from 28.48 to 39.36. The wear depths and worn surface area values ranged from 1.12 to 10.79 μm and from 6.74 to 161.95 μm(2). The data revealed that the modified artificial denture teeth were significantly harder and exhibited significantly higher wear resistance than did the conventional artificial teeth (Ppolymethyl methacrylate modified surface artificial denture teeth was not significantly different from that of the composite resin artificial denture teeth, with the exceptions that the surface was harder and more wear resistant. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  9. Banff initiative for quality assurance in transplantation (BIFQUIT): reproducibility of C4d immunohistochemistry in kidney allografts.

    Science.gov (United States)

    Mengel, M; Chan, S; Climenhaga, J; Kushner, Y B; Regele, H; Colvin, R B; Randhawa, P

    2013-05-01

    Detection of C4d is crucial for diagnosing antibody-mediated-rejection. We conducted a multicenter trial to assess the reproducibility for C4d immunohistochemistry on paraffin tissue. Unstained slides from a tissue microarray (TMA) comprising 44 kidney allograft specimens representing a full analytical spectrum for C4d were distributed to 73 institutions. Participants stained TMA slides using local protocols and evaluated their slides following the Banff C4d schema. Local staining details and evaluation scores were collected online. Stained slides were returned for centralized panel re-evaluation. Kappa statistics were used to determine reproducibility. Poor interinstitutional reproducibility was observed (kappa 0.17), which was equally due to limitations in interobserver (kappa 0.44) and interlaboratory reproducibility (kappa 0.46). Depending on the cut-off, reproducibility could be improved by omitting C4d grading and only considering ± calls. Heat-induced epitope recovery (pH 6-7, 20-30 min, citrate buffer) with polyclonal antibody incubation (40 min) appeared as best practice. The BIFQUIT trial results indicated that C4d staining on paraffin sections varies considerably between laboratories. Refinement of the current Banff C4d scoring schema and harmonization of tissue processing and staining protocols is necessary to achieve acceptable reproducibility. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

  10. Deriving C4 photosynthetic parameters from combined gas exchange and chlorophyll fluorescence using an Excel tool: theory and practice.

    Science.gov (United States)

    Bellasio, Chandra; Beerling, David J; Griffiths, Howard

    2016-06-01

    The higher photosynthetic potential of C4 plants has led to extensive research over the past 50 years, including C4 -dominated natural biomes, crops such as maize, or for evaluating the transfer of C4 traits into C3 lineages. Photosynthetic gas exchange can be measured in air or in a 2% Oxygen mixture using readily available commercial gas exchange and modulated PSII fluorescence systems. Interpretation of these data, however, requires an understanding (or the development) of various modelling approaches, which limit the use by non-specialists. In this paper we present an accessible summary of the theory behind the analysis and derivation of C4 photosynthetic parameters, and provide a freely available Excel Fitting Tool (EFT), making rigorous C4 data analysis accessible to a broader audience. Outputs include those defining C4 photochemical and biochemical efficiency, the rate of photorespiration, bundle sheath conductance to CO2 diffusion and the in vivo biochemical constants for PEP carboxylase. The EFT compares several methodological variants proposed by different investigators, allowing users to choose the level of complexity required to interpret data. We provide a complete analysis of gas exchange data on maize (as a model C4 organism and key global crop) to illustrate the approaches, their analysis and interpretation. © 2015 John Wiley & Sons Ltd. © 2016 John Wiley & Sons Ltd.

  11. Functional recruitment of human complement inhibitor C4B-binding protein to outer membrane protein Rck of Salmonella.

    Directory of Open Access Journals (Sweden)

    Derek K Ho

    Full Text Available Resistance to complement mediated killing, or serum resistance, is a common trait of pathogenic bacteria. Rck is a 17 kDa outer membrane protein encoded on the virulence plasmid of Salmonella enterica serovars Typhimurium and Enteritidis. When expressed in either E. coli or S. enterica Typhimurium, Rck confers LPS-independent serum resistance as well as the ability to bind to and invade mammalian cells. Having recently shown that Rck binds the inhibitor of the alternative pathway of complement, factor H (fH, we hypothesized that Rck can also bind the inhibitor of the classical and lectin pathways, C4b-binding protein (C4BP. Using flow cytometry and direct binding assays, we demonstrate that E. coli expressing Rck binds C4BP from heat-inactivated serum and by using the purified protein. No binding was detected in the absence of Rck expression. C4BP bound to Rck is functional, as we observed factor I-mediated cleavage of C4b in cofactor assays. In competition assays, binding of radiolabeled C4BP to Rck was reduced by increasing concentrations of unlabeled protein. No effect was observed by increasing heparin or salt concentrations, suggesting mainly non-ionic interactions. Reduced binding of C4BP mutants lacking complement control protein domains (CCPs 7 or 8 was observed compared to wt C4BP, suggesting that these CCPs are involved in Rck binding. While these findings are restricted to Rck expression in E. coli, these data suggest that C4BP binding may be an additional mechanism of Rck-mediated complement resistance.

  12. Elevated levels of the complement activation product C4d in bronchial fluids for the diagnosis of lung cancer.

    Directory of Open Access Journals (Sweden)

    Daniel Ajona

    Full Text Available Molecular markers in bronchial fluids may contribute to the diagnosis of lung cancer. We previously observed a significant increase of C4d-containing complement degradation fragments in bronchoalveolar lavage (BAL supernatants from lung cancer patients in a cohort of 50 cases and 22 controls (CUN cohort. The present study was designed to determine the diagnostic performance of these complement fragments (hereinafter jointly referred as C4d in bronchial fluids. C4d levels were determined in BAL supernatants from two independent cohorts: the CU cohort (25 cases and 26 controls and the HUVR cohort (60 cases and 98 controls. A series of spontaneous sputum samples from 68 patients with lung cancer and 10 controls was also used (LCCCIO cohort. Total protein content, complement C4, complement C5a, and CYFRA 21-1 were also measured in all cohorts. C4d levels were significantly increased in BAL samples from lung cancer patients. The area under the ROC curve was 0.82 (95%CI = 0.71-0.94 and 0.67 (95%CI = 0.58-0.76 for the CU and HUVR cohorts, respectively. In addition, unlike the other markers, C4d levels in BAL samples were highly consistent across the CUN, CU and HUVR cohorts. Interestingly, C4d test markedly increased the sensitivity of bronchoscopy in the two cohorts in which cytological data were available (CUN and HUVR cohorts. Finally, in the LCCCIO cohort, C4d levels were higher in sputum supernatants from patients with lung cancer (area under the ROC curve: 0.7; 95%CI = 0.56-0.83. In conclusion, C4d is consistently elevated in bronchial fluids from lung cancer patients and may be used to improve the diagnosis of the disease.

  13. Effects of climate and water balance across grasslands of varying C3 and C4 grass cover

    Science.gov (United States)

    Witwicki, Dana L.; Munson, Seth M.; Thoma, David P.

    2016-01-01

    Climate change in grassland ecosystems may lead to divergent shifts in the abundance and distribution of C3 and C4 grasses. Many studies relate mean climate conditions over relatively long time periods to plant cover, but there is still much uncertainty about how the balance of C3and C4 species will be affected by climate at a finer temporal scale than season (individual events to months). We monitored cover at five grassland sites with co-dominant C3 and C4 grass species or only dominant C3 grass species for 6 yr in national parks across the Colorado Plateau region to assess the influence of specific months of climate and water balance on changes in grass cover. C4 grass cover increased and decreased to a larger degree than C3 grass cover with extremely dry and wet consecutive years, but this response varied by ecological site. Climate and water balance explained 10–49% of the inter-annual variability of cover of C3 and C4 grasses at all sites. High precipitation in the spring and in previous year monsoon storms influenced changes in cover of C4 grasses, with measures of water balance in the same months explaining additional variability. C3 grasses in grasslands where they were dominant were influenced primarily by longer periods of climate, while C3 grasses in grasslands where they were co-dominant with C4 grasses were influenced little by climate anomalies at either short or long periods of time. Our results suggest that future changes in spring and summer climate and water balance are likely to affect cover of both C3 and C4 grasses, but cover of C4 grasses may be affected more strongly, and the degree of change will depend on soils and topography where they are growing and the timing of the growing season.

  14. Starch Accumulation in the Bundle Sheaths of C3 Plants: A Possible Pre-Condition for C4 Photosynthesis.

    Science.gov (United States)

    Miyake, Hiroshi

    2016-05-01

    C4 plants have evolved >60 times from their C3 ancestors. C4 photosynthesis requires a set of closely co-ordinated anatomical and biochemical characteristics. However, it is now recognized that the evolution of C4 plants requires fewer changes than had ever been considered, because of the genetic, biochemical and anatomical pre-conditions of C3 ancestors that were recruited into C4 photosynthesis. Therefore, the pre-conditions in C3 plants are now being actively investigated to clarify the evolutionary trajectory from C3 to C4 plants and to engineer C4 traits efficiently into C3 crops. In the present mini review, the anatomical characteristics of C3 and C4 plants are briefly reviewed and the importance of the bundle sheath for the evolution of C4 photosynthesis is described. For example, while the bundle sheath of C3 rice plants accumulates large amounts of starch in the developing leaf blade and at the lamina joint of the mature leaf, the starch sheath function is also observed during leaf development in starch accumulator grasses regardless of photosynthetic type. The starch sheath function of C3 plants is therefore also implicated as a possible pre-condition for the evolution of C4 photosynthesis. The phylogenetic relationships between the types of storage carbohydrates and of photosynthesis need to be clarified in the future. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  15. Analisis Perbandingan Teknik Support Vector Regression (SVR) Dan Decision Tree C4.5 Dalam Data Mining

    OpenAIRE

    Astuti, Yuniar Andi

    2011-01-01

    This study examines techniques Support Vector Regression and Decision Tree C4.5 has been used in studies in various fields, in order to know the advantages and disadvantages of both techniques that appear in Data Mining. From the ten studies that use both techniques, the results of the analysis showed that the accuracy of the SVR technique for 59,64% and C4.5 for 76,97% So in this study obtained a statement that C4.5 is better than SVR 097038020

  16. Differences in photosynthetic responses of NADP-ME type C4 species to high light.

    Science.gov (United States)

    Romanowska, Elżbieta; Buczyńska, Alicja; Wasilewska, Wioleta; Krupnik, Tomasz; Drożak, Anna; Rogowski, Paweł; Parys, Eugeniusz; Zienkiewicz, Maksymilian

    2017-03-01

    Three species chosen as representatives of NADP-ME C4 subtype exhibit different sensitivity toward photoinhibition, and great photochemical differences were found to exist between the species. These characteristics might be due to the imbalance in the excitation energy between the photosystems present in M and BS cells, and also due to that between species caused by the penetration of light inside the leaves. Such regulation in the distribution of light intensity between M and BS cells shows that co-operation between both the metabolic systems determines effective photosynthesis and reduces the harmful effects of high light on the degradation of PSII through the production of reactive oxygen species (ROS). We have investigated several physiological parameters of NADP-ME-type C4 species (e.g., Zea mays, Echinochloa crus-galli, and Digitaria sanguinalis) grown under moderate light intensity (200 µmol photons m -2  s -1 ) and, subsequently, exposed to excess light intensity (HL, 1600 µmol photons m -2  s -1 ). Our main interest was to understand why these species, grown under identical conditions, differ in their responses toward high light, and what is the physiological significance of these differences. Among the investigated species, Echinochloa crus-galli is best adapted to HL treatment. High resistance of the photosynthetic apparatus of E. crus-galli to HL was accompanied by an elevated level of phosphorylation of PSII proteins, and higher values of photochemical quenching, ATP/ADP ratio, activity of PSI and PSII complexes, as well as integrity of the thylakoid membranes. It was also shown that the non-radiative dissipation of energy in the studied plants was not dependent on carotenoid contents and, thus, other photoprotective mechanisms might have been engaged under HL stress conditions. The activity of the enzymes superoxide dismutase and ascorbate peroxidase as well as the content of malondialdehyde and H 2 O 2 suggests that antioxidant defense is not

  17. Effects of radiation damping on photorecombination of C4 + ions for the KLL resonance

    Science.gov (United States)

    Li, Chuan-Ying; Wu, Yong; Qu, Yi-Zhi; Wang, Jian-Guo

    2016-10-01

    A numerical method based on Zabaydullin and Dubau's work [O. Zabaydullin and J. Dubau, J. Phys. B: At. Mol. Opt. Phys. 45, 115002 (2012), 10.1088/0953-4075/45/11/115002] has been developed to calculate the Cauchy principal value integral in scattering matrices and obtain photorecombination (PR) cross sections of low-lying resonances according to Davies and Seaton's theory [J. Phys. B 2, 757 (1969), 10.1088/0022-3700/2/7/304], in which radiation damping is included. The Dirac R -matrix method is employed to secure the dipole matrix. Using this method, PR cross sections of C4 + for the KLL resonance are acquired, and compared with available experimental measurements and other close-coupling theoretical results. It is shown that our damped cross sections reproduce the experimental data and are in agreement with other theoretical results. Meanwhile, radiation damping can reduce the PR cross section for the 1 s 2 p22P resonance (corresponding to two levels [(1s2p1 /2) 12 p3 /2] 1 /2 and [1s (2p3/22)2] 3 /2 by three orders of magnitude. The unresolved and underestimated resonances 1 s 2 p24P , 1 s 2 s 2 p 4P , and 1 s 2 p22P in the undamped Breit-Pauli R -matrix calculations [H. L. Zhang et al., J. Phys. B: At. Mol. Opt. Phys. 32, 1459 (1999), 10.1088/0953-4075/32/6/010] are corrected. Besides, dielectronic recombination cross sections of C4 + for the KLL resonance are also presented for comparison using the relativistic configuration-interaction (RCI) method implemented in flexible atomic code (fac), which show radiation damping has pronounced influences on 1 s 2 p22P due to much larger radiative rates compared with autoionization rates. Furthermore, radiative and autoionization rates for the intermediate states [(1s2p1 /2) 12 p3 /2] 1 /2 and [1s (2p3/22)2] 3 /2 of the He-like ions with 6 ≤Z ≤83 are calculated using fac, scaling laws of which are checked. Autoionization rates comply with the Zeff0 scaling law for Z ≥32 , which is caused by relativistic effects.

  18. Comparison of carbon balance in Mediterranean pilot constructed wetlands vegetated with different C4 plant species.

    Science.gov (United States)

    Barbera, Antonio C; Borin, Maurizio; Cirelli, Giuseppe L; Toscano, Attilio; Maucieri, Carmelo

    2015-02-01

    This study investigates carbon dioxide (CO2) and methane (CH4) emissions and carbon (C) budgets in a horizontal subsurface flow pilot-plant constructed wetland (CW) with beds vegetated with Cyperus papyrus L., Chrysopogon zizanioides (L.) Roberty, and Mischantus × giganteus Greef et Deu in the Mediterranean basin (Sicily) during the 1st year of plant growing season. At the end of the vegetative season, M. giganteus showed the higher biomass accumulation (7.4 kg m(-2)) followed by C. zizanioides (5.3 kg m(-2)) and C. papyrus (1.8 kg m(-2)). Significantly higher emissions of CO2 were detected in the summer, while CH4 emissions were maximum during spring. Cumulative CO2 emissions by C. papyrus and C. zizanioides during the monitoring period showed similar trends with final values of about 775 and 1,074 g m(-2), respectively, whereas M. giganteus emitted 3,395 g m(-2). Cumulative CH4 bed emission showed different trends for the three C4 plant species in which total gas release during the study period was for C. papyrus 12.0 g m(-2) and ten times higher for M. giganteus, while C. zizanioides bed showed the greatest CH4 cumulative emission with 240.3 g m(-2). The wastewater organic carbon abatement determined different C flux in the atmosphere. Gas fluxes were influenced both by plant species and monitored months with an average C-emitted-to-C-removed ratio for C. zizanioides, C. papyrus, and M. giganteus of 0.3, 0.5, and 0.9, respectively. The growing season C balances were positive for all vegetated beds with the highest C sequestered in the bed with M. giganteus (4.26 kg m(-2)) followed by C. zizanioides (3.78 kg m(-2)) and C. papyrus (1.89 kg m(-2)). To our knowledge, this is the first paper that presents preliminary results on CO2 and CH4 emissions from CWs vegetated with C4 plant species in Mediterranean basin during vegetative growth.

  19. [Experimental study on novel hybrid artificial trachea transplantation].

    Science.gov (United States)

    Liu, Wenliang; Xiao, Peng; Liang, Hengxing; An, Ran; Cheng, Gang; Yu, Fenglei

    2014-04-01

    We developed and designed a new type of artificial trachea. The basic structure of the artificial trachea was polytetrafluoroethylene vascular prosthesis linked with titanium rings on both sides. Dualmesh was sutured on titanium rings. This experimentation follows the replacement of trachea in dogs with a combined artificial trachea to investigate the feasibility of this type of prosthesis. Sixteen dogs were implanted with the combined artificial trachea after resection of 5 cm of cervical trachea. The 5 cm-long trachea of dogs on the necks were resected and the reconstruction of the defect of the trachea was performed with trachea prosthesis. According to the method of trachea reconstruction, the models were divided into 2 groups, artificial trachea implantation group (the control group, n = 8) and group of artificial trachea implantation with growth factor (the experimental group, n = 8). Then computer tomography scan (CT), bronchoscope and pathologic examination were conducted periodically to observe the healing state of the hybrid artificial trachea. None of the dogs died during operation of cervical segmental trachea construction. But four dogs in the control group died of apnea in succession because artificial trachea was displaced and the lumen was obstructed, while 2 dogs died in the experimental group. In the first month there was granulation around anastomosis with slight stenosis. The rest of dogs were well alive until they were sacrificed 14 months later. The mean survival time of the experimental group was longer than that of the control group. The rate of infection, anastomotic dehiscence, severe stenosis and accidental death in the experimental group were lower than the control group (P anastomosis effectively but infections and split or displacement of the artificial trachea are still major problems affecting long-term survival of the animals. Application of growth factors to a certain extent promotes tissue healing by changing the local environment.

  20. Cultivating C4 crops in a changing climate: sugarcane in Ghana

    International Nuclear Information System (INIS)

    Black, Emily; Vidale, Pier Luigi; Osborne, Tom; Van den Hoof, Catherine; Verhoef, Anne; Cuadra, Santiago Vianna

    2012-01-01

    Over the next few decades, it is expected that increasing fossil fuel prices will lead to a proliferation of energy crop cultivation initiatives. The environmental sustainability of these activities is thus a pressing issue—particularly when they take place in vulnerable regions, such as West Africa. In more general terms, the effect of increased CO 2 concentrations and higher temperatures on biomass production and evapotranspiration affects the evolution of the global hydrological and carbon cycles. Investigating these processes for a C4 crop, such as sugarcane, thus provides an opportunity both to extend our understanding of the impact of climate change, and to assess our capacity to model the underpinning processes. This paper applies a process-based crop model to sugarcane in Ghana (where cultivation is planned), and the São Paulo region of Brazil (which has a well-established sugarcane industry). We show that, in the Daka River region of Ghana, provided there is sufficient irrigation, it is possible to generate approximately 75% of the yield achieved in the São Paulo region. In the final part of the study, the production of sugarcane under an idealized temperature increase climate change scenario is explored. It is shown that doubling CO 2 mitigates the degree of water stress associated with a 4 °C increase in temperature. (letter)

  1. Perfect Octagon Quadrangle Systems with an upper C4-system and a large spectrum

    Directory of Open Access Journals (Sweden)

    Luigia Berardi

    2011-02-01

    Full Text Available An octagon quadrangle is the graph consisting of an 8-cycle (x1, x2,..., x8 with two additional chords: the edges {x1, x4} and {x5, x8}. An octagon quadrangle system of order ν and index λ [OQS] is a pair (X,H, where X is a finite set of ν vertices and H is a collection of edge disjoint octagon quadrangles (called blocks which partition the edge set of λKν defined on X. An octagon quadrangle system Σ=(X,H of order ν and index λ is said to be upper C4-perfect if the collection of all of the upper 4-cycles contained in the octagon quadrangles form a μ-fold 4-cycle system of order ν; it is said to be upper strongly perfect, if the collection of all of the upper 4-cycles contained in the octagon quadrangles form a μ-fold 4-cycle system of order ν and also the collection of all of the outside 8-cycles contained in the octagon quadrangles form a ρ-fold 8-cycle system of order ν. In this paper, the authors determine the spectrum for these systems, in the case that it is the largest possible.

  2. Cultivating C4 crops in a changing climate: sugarcane in Ghana

    Science.gov (United States)

    Black, Emily; Vidale, Pier Luigi; Verhoef, Anne; Vianna Cuadra, Santiago; Osborne, Tom; Van den Hoof, Catherine

    2012-12-01

    Over the next few decades, it is expected that increasing fossil fuel prices will lead to a proliferation of energy crop cultivation initiatives. The environmental sustainability of these activities is thus a pressing issue—particularly when they take place in vulnerable regions, such as West Africa. In more general terms, the effect of increased CO2 concentrations and higher temperatures on biomass production and evapotranspiration affects the evolution of the global hydrological and carbon cycles. Investigating these processes for a C4 crop, such as sugarcane, thus provides an opportunity both to extend our understanding of the impact of climate change, and to assess our capacity to model the underpinning processes. This paper applies a process-based crop model to sugarcane in Ghana (where cultivation is planned), and the São Paulo region of Brazil (which has a well-established sugarcane industry). We show that, in the Daka River region of Ghana, provided there is sufficient irrigation, it is possible to generate approximately 75% of the yield achieved in the São Paulo region. In the final part of the study, the production of sugarcane under an idealized temperature increase climate change scenario is explored. It is shown that doubling CO2 mitigates the degree of water stress associated with a 4 °C increase in temperature.

  3. Development of Digital I and C System using C4ISR Architect Framework

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jae Cheon [KEPCO, Ulsan (Korea, Republic of); Quang, Phamle [Ninh Thuan Nuclear Power Project Management Board, Province (Viet Nam)

    2014-08-15

    The architect framework for the digital I and C system is presented in this work. With rapid changes in digital I and C technology, there is a strong need to provide uniform methods to describe the system functions and their performance in context with the physical configuration and logical behavior. C4ISR framework would provide the process and method for the digital system in that it allows the three different views of operational, systems and services, and technical standards. Therefore, stake holders can share information that is related to the system interfaces, the actions or activities that those components perform, and rules or constraints for those activities from the initial state of system development. As a result, the life cycle cost and development time for the digital I and C system can also be optimized. These benefits can be obtained by introducing views and products to reveal the logical, behavioral, and performance characteristics of the architecture. To prove this approach, the plant protection system (PPS) is chosen and the measure of effectiveness (MOE) is evaluated. An MOE of PPS is introduced as: functional effectiveness, performance effectiveness, and interoperability effectiveness.

  4. Water relations of native and introduced C4grasses in a neotropical savanna.

    Science.gov (United States)

    Baruch, Zdravko; Fernández, Denny S

    1993-11-01

    Introduced African grasses are invading Neotropical savannas and displacing the native herbaceous community. This work, which is part of a program to understand the success of the African grasses, specifically investigates whether introduced and native grasses differ in their water relations. The water relations of the native Trachypogon plumosus and the successful invader Hyparrhenia rufa were studied in the field during two consecutive years in the seasonal savannas of Venezuela. The two C 4 grasses differed clearly in their responses to water stress. H. rufa consistently had higher stomatal conductance, transpiration rate, leaf water and osmotic potential and osmotic adjustment than the native T. plumosus. Also, leaf senescence occurred much earlier during the dry season in H. rufa. Both grasses showed a combination of water stress evasion and tolerance mechanisms such as stomatal sensitivity to atmospheric or soil water stress, decreased transpiring area and osmotic adjustment. Evasion mechanisms are more conspicuous in H. rufa whereas T. plumosus is more drought tolerant and uses water more "conservatively". The evasion mechanisms and oportunistic use of water by H. rufa, characteristic of invading species, contribute to, but only partially explain, the success of this grass in the Neotropical savannas where it displaces native plants from sites with better water and nutrient status. Conversely, the higher water stress tolerance of t. plumosus is consistent with its capacity to resist invasion by alien grasses on shallow soils and sites with poorer nutrient and water status.

  5. Approach to Interfacial and Intramolecular Electron Transfer of the Diheme Protein Cytochrome c(4) Assembled on Au(111) Surfaces

    DEFF Research Database (Denmark)

    Chi, Qijin; Zhang, Jingdong; Taner, Arslan

    2010-01-01

    protein Pseudomonas stutzeri cytochrome c(4) has been a target for intramolecular, interheme ET. We report here voltammetric and in situ scanning tunneling microscopy (STM) data for P. stutzeri cyt c(4) at single-crystal, atomically planar Au(111)-electrode surfaces modified by variable-length omega...... direction and a single two-ET peak in the anodic direction. Intramolecular, interheme ET with high, 8,000-30,000 s(-1), rate constants is notably an essential part of this mechanism. The high rate constants are in striking contrast to ET reactions of P. stutzeri cyt c4 with small reaction partners...... in homogeneous solution for which kinetic analysis clearly testifies to electrostatic cooperative effects but no intramolecular, interheme ET higher than 0.1-10 s(-1). This difference suggests a strong gating feature of the process. On the basis of the three-dimensional structure of P. stutzeri cyt c(4), gating...

  6. Application of the pessimistic pruning to increase the accuracy of C4.5 algorithm in diagnosing chronic kidney disease

    Science.gov (United States)

    Muslim, M. A.; Herowati, A. J.; Sugiharti, E.; Prasetiyo, B.

    2018-03-01

    A technique to dig valuable information buried or hidden in data collection which is so big to be found an interesting patterns that was previously unknown is called data mining. Data mining has been applied in the healthcare industry. One technique used data mining is classification. The decision tree included in the classification of data mining and algorithm developed by decision tree is C4.5 algorithm. A classifier is designed using applying pessimistic pruning in C4.5 algorithm in diagnosing chronic kidney disease. Pessimistic pruning use to identify and remove branches that are not needed, this is done to avoid overfitting the decision tree generated by the C4.5 algorithm. In this paper, the result obtained using these classifiers are presented and discussed. Using pessimistic pruning shows increase accuracy of C4.5 algorithm of 1.5% from 95% to 96.5% in diagnosing of chronic kidney disease.

  7. Synthesis of C3-symmetric and C4-symmetric amino acid derivatives via Suzuki-Miyaura cross-coupling reaction.

    Science.gov (United States)

    Kotha, S; Shah, V R

    2008-06-01

    Various non-natural C(3)- and C(4)-symmetric alpha-amino acid derivatives have been synthesized via Suzuki-Miyaura cross-coupling reaction between aromatic iodides or bromide and a suitably protected DL-4-boronophenylalanine derivative.

  8. Impact of C4ISR/Digitization and Joint Force Ability to Conduct the Global War on Terror (GWOT)

    National Research Council Canada - National Science Library

    Dacus, Andrew P

    2006-01-01

    ..., and international terrorist organizations. Operations in the late twentieth century and early twenty first century have been characterized by a dramatic increase in the use of C4ISR systems, transformation initiatives, and network centric warfare concepts...

  9. Synthesis, crystal structure, thermal analysis and dielectric properties of [(C4H9)4N]3Bi2Cl9 compound

    Science.gov (United States)

    Trigui, W.; Oueslati, A.; Chaabane, I.; Hlel, F.

    2015-07-01

    A new organic-inorganic tri-tetrabutylammonium nonachlorobibismuthate(III) compound was prepared. It was found to crystallize in the monoclinic system (P21/n space group) with the following lattice parameters: a=11.32(2) Å, b=22.30(3) Å, c=28.53(2) Å and β=96.52(0)°. The [Bi2Cl9]3- anions are surrounded by six [(C4H9)N]+ cations, forming an octahedral configuration. These octahedra are sharing corners in order to provide the tri-dimensional network cohesion. The differential scanning calorimetry reveals four order-disorder reversible phase transitions located at 214, 238, 434 and 477 K. The Raman and infrared spectra confirm the presence of both cationic [(C4H9)N]+ and anionic [Bi2Cl9]3- parts. The dielectric parameters, real and imaginary dielectric permittivity (ε‧ and ε″), and dielectric loss tangent (tg δ), were measured in the frequency range of 209 kHz-5 MHz at different temperatures. The variations of dielectric dispersion (ε') and dielectric absorption (ε″) with frequency show a distribution of relaxation times, which is probably related to the change in the dynamical state of the [(C4H9)4N]+ cations and the [Bi2Cl9]3- anions.

  10. Threshold Ionization Spectroscopy of La(CH_{3}CN) and La(C_{4}H_{9}CN) Radicals Formed by la Reactions with Alkane Nitriles

    Science.gov (United States)

    Ullah, Ahamed; Kim, Jong Hyun; Cao, Wenjin; Yang, Dong-Sheng

    2017-06-01

    La atom reactions with acetonitrile (CH_{3}CN) and pentanenitrile (C_{4}H_{9}CN) are carried out in a laser-vaporization supersonic molecular beam source. Metal-containing species are observed using time-of-flight mass spectrometry. In this talk, we report the mass-analyzed threshold ionization (MATI) spectroscopic characterization of two metal-containing radicals, La(CH_{3}CN) and La(C_{4}H_{9}CN), formed by La associations with acetonitrile and pentanenitrile, respectively. Adiabatic ionization energies of the two La-alkane nitrile species and their vibrational frequencies are measured from the MATI spectra. Metal-ligand binding modes and molecular structures are investigated by comparing the spectroscopic measurements with density functional theory calculations and spectral simulations. For both alkane nitriles, the preferred La binding site is identified to be the nitrile group with a π-bind mode, the resultant metal complexes are three-membered metallacycles. While a single isomer is observed for La(CH_{3}CN), two rotational conformers are identified for La(C_{4}H_{9}CN). The binding and structures of these metal-alkane nitrile radicals are different from those formed by metal ion reactions, where metal ions were reported to favor σ binding with the nitrogen atom. K. Eller, W. Zummack, H. Schwarz, L. M. Roth, B. S. Freiser, J. Am. Chem. Soc., 1991, 113, 833-839

  11. Properties of C4F7N–CO2 thermal plasmas: thermodynamic properties, transport coefficients and emission coefficients

    Science.gov (United States)

    Wu, Yi; Wang, Chunlin; Sun, Hao; Murphy, Anthony B.; Rong, Mingzhe; Yang, Fei; Chen, Zhexin; Niu, Chunpin; Wang, Xiaohua

    2018-04-01

    The thermophysical properties, including composition, thermodynamic properties, transport coefficients and net emission coefficients, of thermal plasmas formed from pure iso-C4 perfluoronitrile C4F7N and C4F7N–CO2 mixtures are calculated for temperatures from 300 to 30 000 K and pressures from 0.1 to 20 atm. These gases have received much attention as alternatives to SF6 for use in circuit breakers, due to the low global warming potential and good dielectric properties of C4F7N. Since the parameters of the large molecules formed in the dissociation of C4F7N are unavailable, the partition function and enthalpy of formation were calculated using computational chemistry methods. From the equilibrium composition calculations, it was found that when C4F7N is mixed with CO2, CO2 can capture C atoms from C4F7N, producing CO, since the system consisting of small molecules such as CF4 and CO has lower energy at room temperature. This is in agreement with previous experimental results, which show that CO dominates the decomposition products of C4F7N–CO2 mixtures; it could limit the repeated breaking performance of C4F7N. From the point of view of chemical stability, the mixing ratio of CO2 should therefore be chosen carefully. Through comparison with common arc quenching gases (including SF6, CF3I and C5F10O), it is found that for the temperature range for which electrical conductivity remains low, pure C4F7N has similar ρC p (product of mass density and specific heat) properties to SF6, and higher radiative emission coefficient, properties that are correlated with good arc extinguishing capability. For C4F7N–CO2 mixtures, the electrical conductivity is very close to that of SF6 while the ρC p peak at 7000 K caused by decomposition of CO implies inferior interruption capability to that of SF6. The calculated properties will be useful in arc simulations.

  12. Histone Acetylation Modifications Affect Tissue-Dependent Expression of Poplar Homologs of C4 Photosynthetic Enzyme Genes

    Directory of Open Access Journals (Sweden)

    Yuan Li

    2017-06-01

    Full Text Available Histone modifications play important roles in regulating the expression of C4 photosynthetic genes. Given that all enzymes required for the C4 photosynthesis pathway are present in C3 plants, it has been hypothesized that this expression regulatory mechanism has been conserved. However, the relationship between histone modification and the expression of homologs of C4 photosynthetic enzyme genes has not been well determined in C3 plants. In the present study, we cloned nine hybrid poplar (Populus simonii × Populus nigra homologs of maize (Zea mays C4 photosynthetic enzyme genes, carbonic anhydrase (CA, pyruvate orthophosphate dikinase (PPDK, phosphoenolpyruvate carboxykinase (PCK, and phosphoenolpyruvate carboxylase (PEPC, and investigated the correlation between the expression levels of these genes and the levels of promoter histone acetylation modifications in four vegetative tissues. We found that poplar homologs of C4 homologous genes had tissue-dependent expression patterns that were mostly well-correlated with the level of histone acetylation modification (H3K9ac and H4K5ac determined by chromatin immunoprecipitation assays. Treatment with the histone deacetylase inhibitor trichostatin A further confirmed the role of histone acetylation in the regulation of the nine target genes. Collectively, these results suggest that both H3K9ac and H4K5ac positively regulate the tissue-dependent expression pattern of the PsnCAs, PsnPPDKs, PsnPCKs, and PsnPEPCs genes and that this regulatory mechanism seems to be conserved among the C3 and C4 species. Our findings provide new insight that will aid efforts to modify the expression pattern of these homologs of C4 genes to engineer C4 plants from C3 plants.

  13. A Modified Thermal Time Model Quantifying Germination Response to Temperature for C3 and C4 Species in Temperate Grassland

    Directory of Open Access Journals (Sweden)

    Hongxiang Zhang

    2015-07-01

    Full Text Available Thermal-based germination models are widely used to predict germination rate and germination timing of plants. However, comparison of model parameters between large numbers of species is rare. In this study, seeds of 27 species including 12 C4 and 15 C3 species were germinated at a range of constant temperatures from 5 °C to 40 °C. We used a modified thermal time model to calculate germination parameters at suboptimal temperatures. Generally, the optimal germination temperature was higher for C4 species than for C3 species. The thermal time constant for the 50% germination percentile was significantly higher for C3 than C4 species. The thermal time constant of perennials was significantly higher than that of annuals. However, differences in base temperatures were not significant between C3 and C4, or annuals and perennial species. The relationship between germination rate and seed mass depended on plant functional type and temperature, while the base temperature and thermal time constant of C3 and C4 species exhibited no significant relationship with seed mass. The results illustrate differences in germination characteristics between C3 and C4 species. Seed mass does not affect germination parameters, plant life cycle matters, however.

  14. Theoretical investigation of phase transition on GaAs(0 0 1)-c(4 x 4) surface

    International Nuclear Information System (INIS)

    Ishizaki, Hirotoshi; Akiyama, Toru; Nakamura, Kohji; Shiraishi, Kenji; Taguchi, Akihito; Ito, Tomonori

    2005-01-01

    The surface phase transition between GaAs(0 0 1)-c(4 x 4) and -(2 x 4)β2 surfaces is systematically investigated by using our ab initio-based approach. The phase diagram calculations for the c(4 x 4) surfaces as functions of temperature and As pressure reveal that three kinds of c(4 x 4) surfaces consisting of Ga-As dimers and/or Ga-Ga dimers become stable near the phase transition temperature. The electron counting Monte Carlo simulation and ab initio calculations are also performed to investigate the structural change of the c(4 x 4) surface after predepositing a 0.5 monolayer of Ga on the three kinds of c(4 x 4) surfaces. The calculated results suggest that the c(4 x 4) surfaces consisting of three Ga-As dimers or one Ga-Ga dimer and two Ga-As dimers in the (4 x 4) surface unit cell possibly change their structures to (2 x 4)β2 structures with Ga-As surface dimers. The conventional (2 x 4)β2 surface consisting of As dimers finally appears due to destabilization of Ga-As dimers at high temperature and high pressure

  15. Photosynthetic characteristics of an amphibious plant, Eleocharis vivipara: Expression of C4 and C3 modes in contrasting environments

    International Nuclear Information System (INIS)

    Ueno, Osamu; Samejima, Muneaki; Muto, Shoshi; Miyachi, Shigetoh

    1988-01-01

    Eleocharis vivipara Link, a freshwater amphibious leafless plant belonging to the Cyperaceae can grow in both terrestrial and submersed aquatic conditions. Two forms of E. vivipara obtained from these contrasting environments were examined for the characteristics associated with C 4 and C 3 photosynthesis. In the terrestrial form, the culms, which are photosynthetic organs, possess a Kranz-type anatomy typical of C 4 plants, and well-developed bundle-sheath cells contain numerous large chloroplasts. In the submersed form, the culms possess anatomical features characteristic of submersed aquatic plants, and the reduced bundle-sheath cells contain only a few small chloroplasts. 14 C pulse- 12 C chase experiments showed that the terrestrial form and the submersed form fix carbon by way of the C 4 pathway, with aspartate (40%) and malate (35%) as the main primary products, and by way of the C 3 pathway, with 3-phosphoglyceric acid (53%) and sugar phosphates (14%) as the main primary products, respectively. The terrestrial form showed photosynthetic enzyme activities typical of the NAD-malic enzyme-C 4 subtype, whereas the submersed form showed decreased activities of key C 4 enzymes and an increased ribulose 1,5-bisphosphate carboxylase activity. These data suggest that this species can differentiate into the C 4 mode under terrestrial conditions and into the C 3 mode under submersed conditions

  16. Application of artificial intelligence to the management of urological cancer.

    Science.gov (United States)

    Abbod, Maysam F; Catto, James W F; Linkens, Derek A; Hamdy, Freddie C

    2007-10-01

    Artificial intelligence techniques, such as artificial neural networks, Bayesian belief networks and neuro-fuzzy modeling systems, are complex mathematical models based on the human neuronal structure and thinking. Such tools are capable of generating data driven models of biological systems without making assumptions based on statistical distributions. A large amount of study has been reported of the use of artificial intelligence in urology. We reviewed the basic concepts behind artificial intelligence techniques and explored the applications of this new dynamic technology in various aspects of urological cancer management. A detailed and systematic review of the literature was performed using the MEDLINE and Inspec databases to discover reports using artificial intelligence in urological cancer. The characteristics of machine learning and their implementation were described and reports of artificial intelligence use in urological cancer were reviewed. While most researchers in this field were found to focus on artificial neural networks to improve the diagnosis, staging and prognostic prediction of urological cancers, some groups are exploring other techniques, such as expert systems and neuro-fuzzy modeling systems. Compared to traditional regression statistics artificial intelligence methods appear to be accurate and more explorative for analyzing large data cohorts. Furthermore, they allow individualized prediction of disease behavior. Each artificial intelligence method has characteristics that make it suitable for different tasks. The lack of transparency of artificial neural networks hinders global scientific community acceptance of this method but this can be overcome by neuro-fuzzy modeling systems.

  17. Artificial intelligence in nanotechnology

    International Nuclear Information System (INIS)

    Sacha, G M; Varona, P

    2013-01-01

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines. (topical review)

  18. Artificial organ engineering

    CERN Document Server

    Annesini, Maria Cristina; Piemonte, Vincenzo; Turchetti, Luca

    2017-01-01

    Artificial organs may be considered as small-scale process plants, in which heat, mass and momentum transfer operations and, possibly, chemical transformations are carried out. This book proposes a novel analysis of artificial organs based on the typical bottom-up approach used in process engineering. Starting from a description of the fundamental physico-chemical phenomena involved in the process, the whole system is rebuilt as an interconnected ensemble of elemental unit operations. Each artificial organ is presented with a short introduction provided by expert clinicians. Devices commonly used in clinical practice are reviewed and their performance is assessed and compared by using a mathematical model based approach. Whilst mathematical modelling is a fundamental tool for quantitative descriptions of clinical devices, models are kept simple to remain focused on the essential features of each process. Postgraduate students and researchers in the field of chemical and biomedical engineering will find that t...

  19. Artificial intelligence in nanotechnology.

    Science.gov (United States)

    Sacha, G M; Varona, P

    2013-11-15

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines.

  20. Effects of substitution on counterflow ignition and extinction of C3 and C4 alcohols

    KAUST Repository

    Alfazazi, Adamu

    2016-06-17

    Dwindling reserves and inherent uncertainty in the price of conventional fuels necessitates a search for alternative fuels. Alcohols represent a potential source of energy for the future. The structural features of an alcohol fuel have a direct impact on combustion properties. In particular, substitution in alcohols can alter the global combustion reactivity. In this study, experiments and numerical simulations were conducted to investigate the critical conditions of extinction and autoignition of n-propanol, 1-butanol, iso-propanol and iso-butanol in non-premixed diffusion flames. Experiments were carried out in the counterflow configuration, while simulations were conducted using a skeletal chemical kinetic model for the C3 and C4 alcohols. The fuel stream consists of the pre-vaporized fuel diluted with nitrogen, while the oxidizer stream is air. The experimental results show that autoignition temperatures of the tested alcohols increase in the following order: iso-propanol > iso-butanol > 1-butanol ≈ n-propanol. The simulated results for the branched alcohols agree with the experiments, while the autoignition temperature of 1-butanol is slightly higher than that of n-propanol. For extinction, the experiments show that the extinction limits of the tested fuels increase in the following order: n-propanol ≈ 1-butanol > iso-butanol > iso-propanol. The model suggests that the extinction limits of 1-butanol is slightly higher than n-propanol with extinction strain rate of iso-butanol and iso-propanol maintaining the experimentally observed trend. The transport weighted enthalpy (TWE) and radical index (Ri) concepts were utilized to rationalize the observed reactivity trends for these fuels.

  1. Artificial intelligence in cardiology.

    Science.gov (United States)

    Bonderman, Diana

    2017-12-01

    Decision-making is complex in modern medicine and should ideally be based on available data, structured knowledge and proper interpretation in the context of an individual patient. Automated algorithms, also termed artificial intelligence that are able to extract meaningful patterns from data collections and build decisions upon identified patterns may be useful assistants in clinical decision-making processes. In this article, artificial intelligence-based studies in clinical cardiology are reviewed. The text also touches on the ethical issues and speculates on the future roles of automated algorithms versus clinicians in cardiology and medicine in general.

  2. Artificial intelligence executive summary

    International Nuclear Information System (INIS)

    Wamsley, S.J.; Purvis, E.E. III

    1984-01-01

    Artificial intelligence (AI) is a high technology field that can be used to provide problem solving diagnosis, guidance and for support resolution of problems. It is not a stand alone discipline, but can also be applied to develop data bases for retention of the expertise that is required for its own knowledge base. This provides a way to retain knowledge that otherwise may be lost. Artificial Intelligence Methodology can provide an automated construction management decision support system, thereby restoring the manager's emphasis to project management

  3. Bayesian artificial intelligence

    CERN Document Server

    Korb, Kevin B

    2003-01-01

    As the power of Bayesian techniques has become more fully realized, the field of artificial intelligence has embraced Bayesian methodology and integrated it to the point where an introduction to Bayesian techniques is now a core course in many computer science programs. Unlike other books on the subject, Bayesian Artificial Intelligence keeps mathematical detail to a minimum and covers a broad range of topics. The authors integrate all of Bayesian net technology and learning Bayesian net technology and apply them both to knowledge engineering. They emphasize understanding and intuition but also provide the algorithms and technical background needed for applications. Software, exercises, and solutions are available on the authors' website.

  4. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  5. Multi-proxy evidence for tectonic control on the expansion of C4 grasses in northwest Argentina

    Science.gov (United States)

    Cotton, Jennifer M.; Hyland, Ethan G.; Sheldon, Nathan D.

    2014-06-01

    The timing of the rise of C4 grasses and the climatic conditions driving their expansion are widely debated, with recent studies suggesting that the expansion was more complex than previously thought. Proxy reconstructions from northwestern Argentina record multiple increases and decreases in C4 abundance throughout the late Miocene to early Pliocene, as well as variations in the timing of the spread of C4 grasses into the region. Here we present a multi-proxy paleovegetation reconstruction of the proportions of C3 and C4 vegetation using organic carbon and phytoliths preserved in paleosols at Entre Ríos in the Santa María Basin of Catamarca, Argentina between 6.2 and 3.3 Ma. Both δCorg13 and phytolith assemblages indicate a C3 dominated ecosystem with no evidence for substantial amounts of C4 vegetation from the late Miocene through mid-Pliocene, despite their rise to dominance elsewhere during this time. These data suggest that by 6.2 Ma the Santa María basin floor was at an elevation high enough to create locally cool conditions that allowed C3 vegetation to outcompete C4 grasses. Phytolith assemblages show that later uplift of the Sierra Calchaquies and Sierra Aconquija ranges through the Pliocene increased aridity and drove the expansion of C3 grasses at the expense of palms and other forest indicators. This multi-proxy paleovegetation reconstruction demonstrates that tectonics played an important role in controlling the late Miocene expansion C4 grasses by suppressing their spread into northwest Argentina.

  6. A Reversible, Charge-Induced Intramolecular C4a-S-Cysteinyl-Flavin in Choline Oxidase Variant S101C.

    Science.gov (United States)

    Su, Dan; Yuan, Hongling; Gadda, Giovanni

    2017-12-26

    Choline oxidase serves as a paradigm for alcohol oxidation catalyzed by flavin-dependent enzymes. In its active site, S101 is 4 Å from the flavin C4a atom on an extended loop. Enzyme variants substituted at S101 were generated in a previous study and investigated mechanistically [Yuan, H., and Gadda, G. (2011) Biochemistry 50, 770-779]. In this study, the typical ultraviolet-visible (UV-vis) absorption spectrum of oxidized flavin was observed for the S101C enzyme in HEPES, TES, or sodium phosphate, whereas an absorption spectrum suggesting the presence of a C4a-flavin adduct with cysteine was obtained in Tris-HCl at pH 8.0. pH titrations of the UV-vis absorption spectrum of the wild-type, S101A, S101C, and H99N enzymes in the presence and absence of Tris allowed for the determination of two pK a values that define a pH range in which the C4a-S-cysteinyl flavin is stabilized. Inhibition studies and stopped-flow kinetics demonstrated that binding of protonated Tris in the active site of the S101C enzyme is required to form the C4a-S-cysteinyl flavin. Deuterium kinetic isotope effects and proton inventories of the S101C enzyme mixed in a stopped-flow spectrophotometer with Tris established a mechanism for the reversible formation of the C4a-S-cysteinyl flavin. This study provides a detailed mechanistic analysis of the reversible formation of a bicovalent C4a-S-cysteinyl-8α-N 3 -histidyl flavin in choline oxidase, identifying an optimal pH range and a mechanistic rationale for the stabilization of de novo C4a-S-cysteinyl-flavins. Moreover, it presents an example of an intramolecular reaction of an enzyme-bound flavin without a substrate.

  7. Interaction between C 4 barnyard grass and C 3 upland rice under elevated CO 2: Impact of mycorrhizae

    Science.gov (United States)

    Tang, Jianjun; Xu, Liming; Chen, Xin; Hu, Shuijin

    2009-03-01

    Atmospheric CO 2 enrichment may impact arbuscular mycorrhizae (AM) development and function, which could have subsequent effects on host plant species interactions by differentially affecting plant nutrient acquisition. However, direct evidence illustrating this scenario is limited. We examined how elevated CO 2 affects plant growth and whether mycorrhizae mediate interactions between C 4 barnyard grass ( Echinochloa crusgalli (L.) Beauv.) and C 3 upland rice ( Oryza sativa L.) in a low nutrient soil. The monocultures and combinations with or without mycorrhizal inoculation were grown at ambient (400 ± 20 μmol mol -1) and elevated CO 2 (700 ± 20 μmol mol -1) levels. The 15N isotope tracer was introduced to quantify the mycorrhizally mediated N acquisition of plants. Elevated CO 2 stimulated the growth of C 3 upland rice but not that of C 4 barnyard grass under monoculture. Elevated CO 2 also increased mycorrhizal colonization of C 4 barnyard grass but did not affect mycorrhizal colonization of C 3 upland rice. Mycorrhizal inoculation increased the shoot biomass ratio of C 4 barnyard grass to C 3 upland rice under both CO 2 concentrations but had a greater impact under the elevated than ambient CO 2 level. Mycorrhizae decreased relative interaction index (RII) of C 3 plants under both ambient and elevated CO 2, but mycorrhizae increased RII of C 4 plants only under elevated CO 2. Elevated CO 2 and mycorrhizal inoculation enhanced 15N and total N and P uptake of C 4 barnyard grass in mixture but had no effects on N and P acquisition of C 3 upland rice, thus altering the distribution of N and P between the species in mixture. These results implied that CO 2 stimulation of mycorrhizae and their nutrient acquisition may impact competitive interaction of C 4 barnyard grass and C 3 upland rice under future CO 2 scenarios.

  8. Genome-Wide Association Study for Serum Complement C3 and C4 Levels in Healthy Chinese Subjects

    Science.gov (United States)

    Tao, Sha; Chen, Zhuo; Kim, Seong-Tae; Peng, Tao; Liao, Ming; Lin, Xiaoling; Zhang, Zengfeng; Tang, Minzhong; Li, Li; Mo, Linjian; Liang, Zhengjia; Shi, Deyi; Huang, Zhang; Huang, Xianghua; Liu, Ming; Liu, Qian; Zhang, Shijun; Trent, Jeffrey M.; Zheng, S. Lilly; Xu, Jianfeng; Mo, Zengnan

    2012-01-01

    Complement C3 and C4 play key roles in the main physiological activities of complement system, and their deficiencies or over-expression are associated with many clinical infectious or immunity diseases. A two-stage genome-wide association study (GWAS) was performed for serum levels of C3 and C4. The first stage was conducted in 1,999 healthy Chinese men, and the second stage was performed in an additional 1,496 subjects. We identified two SNPs, rs3753394 in CFH gene and rs3745567 in C3 gene, that are significantly associated with serum C3 levels at a genome-wide significance level (P = 7.33×10−11 and P = 1.83×10−9, respectively). For C4, one large genomic region on chromosome 6p21.3 is significantly associated with serum C4 levels. Two SNPs (rs1052693 and rs11575839) were located in the MHC class I area that include HLA-A, HLA-C, and HLA-B genes. Two SNPs (rs2075799 and rs2857009) were located 5′ and 3′ of C4 gene. The other four SNPs, rs2071278, rs3763317, rs9276606, and rs241428, were located in the MHC class II region that includes HLA-DRA, HLA-DRB, and HLA-DQB genes. The combined P-values for those eight SNPs ranged from 3.19×10−22 to 5.62×10−97. HBsAg-positive subjects have significantly lower C3 and C4 protein concentrations compared with HBsAg-negative subjects (P<0.05). Our study is the first GWAS report which shows genetic components influence the levels of complement C3 and C4. Our significant findings provide novel insights of their related autoimmune, infectious diseases, and molecular mechanisms. PMID:23028341

  9. Volumetric Properties of the Mixture 3-Thiapentane C4H10S + C6H14 Hexane (VMSD1111, LB3276_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture 3-Thiapentane C4H10S + C6H14 Hexane (VMSD1111, LB3276_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  10. Volumetric Properties of the Mixture 3-Thiapentane C4H10S + C6H14 Hexane (VMSD1212, LB3249_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture 3-Thiapentane C4H10S + C6H14 Hexane (VMSD1212, LB3249_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  11. Competition among warm season C4-cereals influence water use efficiency and competition ratios

    Directory of Open Access Journals (Sweden)

    Amanullah

    2015-12-01

    Full Text Available Water use efficiency (WUE and competition ratio (CR response of three warm season C4-cereals (grasses viz. corn (Zea mays L., cv. Hybrid-5393 VT3, grain sorghum (Sorghum bicolor L. Moench, cv. Hybrid-84G62 PAT, and foxtail millets (Setaria italic, cv. German Strain R in pure and mixed stands under low and high water levels was investigated. The experiment was conducted in pot experiment at Dryland Agriculture Institute, West Texas A&M University, Canyon, Texas, USA, during spring 2010. The objective of this study was to know whether the differences in the competitive ability of different crop species influence WUE or not? The planned mean comparison indicated that the corn WUE was 20, 11, and 6% higher in the mixed stand than in pure stand at 30, 60, and 90 days after emergence (DAE, respectively. The corn plants in pure stand had 91, 72, and 81% higher WUE than the average WUE of sorghum and millets in pure stand at 30, 60, and 90 DAE, respectively. Grain sorghum in pure stand had 70, 32, and 36% higher WUE than that of millets in pure stand at 30, 60, and 90 DAE, respectively. The WUE of three crops in mixed stand was 10 and 8% higher than the two crops mixed stand at the two early stages; but the WUE was 24% less in the three crops mixed stand than the two crops mixed stand at 90 DAE. Corn-mixed stand in two crops (average of corn + sorghum and corn + millets had 78, 74, and 74% higher WUE than the mixed stand of sorghum and millets at 30, 60, and 90 DAE, respectively. Corn and millets mixed stand had 14, 10, and 26% higher WUE than the corn and sorghum mixed stand at 30, 60, and 90 DAE, respectively. The increase in water level decreased WUE at the two late growth stages in all three crop plants. At the early growth stage (30 DAE, WUE increased in all crops at the higher water level. On the basis of CR, corn was found the best competitor, while millets was declared the least competitor in the mixed stands (corn

  12. A shock tube study of C4–C6 straight chain alkenes + OH reactions

    KAUST Repository

    Khaled, Fathi

    2016-06-28

    Alkenes are known to be good octane boosters and they are major components of commercial fuels. Detailed theoretical calculations and direct kinetic measurements of elementary reactions of alkenes with combustion radicals are scarce for C4 alkenes and they are practically absent for C5 and larger alkenes. The overall rate coefficients for the reaction of OH radical with 1-butene (CH CHCH CH, k ), 1-pentene (CH CHCH CH-CH, k ), cis/trans 2-pentene (CH CHCHCH CH, k and k ), 1-hexene (CH CHCH CH CH CH, k ) and cis/trans 2-hexene (CH CHCHCH CH CH, k and k ) were measured behind reflected shock waves over the temperature range of 833-1377K and pressures near 1.5atm. The reaction progress was followed by measuring mole fraction of OH radicals near 306.7nm using UV laser absorption technique. It is found that the rate coefficients of OH+trans-2-alkenes are larger than those of OH+cis-2-alkenes, followed by OH+1-alkenes. The derived Arrhenius expressions for the overall rate coefficients (in cm.mol.s) are:. kI=(4.83±0.03)104.T2.72±0.01.exp(940.8±2.9cal/molRT)(946K-1256K) + kII=(5.66±0.54)10-1.T4.14±0.80.exp(4334±227cal/molRT)(875K-1379K) + kIII=(3.25±0.12)104.T2.76±0.5.exp(1962±83cal/molRT)(877K-1336K) + kIV=(3.42±0.09)104.T2.76±0.5.exp(1995±59cal/molRT)(833K-1265K) + kV=(7.65±0.58)10-4.T5±1.exp(5840±175cal/molRT)(836K-1387K) + kVI=(2.58±0.06)106.T2.17±0.37.exp(1461±55cal/molRT)(891K-1357K) + kVII=(3.08±0.05)106.T2.18±0.37.exp(1317±38cal/molRT)(881K-1377K) +

  13. Artificial intelligence within AFSC

    Science.gov (United States)

    Gersh, Mark A.

    1990-01-01

    Information on artificial intelligence research in the Air Force Systems Command is given in viewgraph form. Specific research that is being conducted at the Rome Air Development Center, the Space Technology Center, the Human Resources Laboratory, the Armstrong Aerospace Medical Research Laboratory, the Armamant Laboratory, and the Wright Research and Development Center is noted.

  14. Generality in Artificial Intelligence

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 3. Generality in Artificial Intelligence. John McCarthy. Classics Volume 19 Issue 3 March 2014 pp 283-296. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/019/03/0283-0296. Author Affiliations.

  15. Artificial Gravity Research Plan

    Science.gov (United States)

    Gilbert, Charlene

    2014-01-01

    This document describes the forward working plan to identify what countermeasure resources are needed for a vehicle with an artificial gravity module (intermittent centrifugation) and what Countermeasure Resources are needed for a rotating transit vehicle (continuous centrifugation) to minimize the effects of microgravity to Mars Exploration crewmembers.

  16. Artificial Intelligence and CALL.

    Science.gov (United States)

    Underwood, John H.

    The potential application of artificial intelligence (AI) to computer-assisted language learning (CALL) is explored. Two areas of AI that hold particular interest to those who deal with language meaning--knowledge representation and expert systems, and natural-language processing--are described and examples of each are presented. AI contribution…

  17. Generality in Artificial Intelligence

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 3. Generality in Artificial Intelligence. John McCarthy. Classics Volume 19 Issue 3 March 2014 pp 283-296. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/019/03/0283-0296. Author Affiliations.

  18. Response of photosynthetic characters to CO2 change on C3 and C4 cereal crops grown in Lunar Palace 1

    Science.gov (United States)

    Wang, Minjuan; Liu, Hong; Fu, Yuming; Shao, Lingzhi; Dong, Chen; Liu, Guanghui

    Lunar Palace 1, as an integrative experiment facility for Permanent Astrobase Life-support Artificial Closed Ecosystem (P.A.L.A.C.E.), provides a largely closed environment for crop growth tests for Bioregenerative Life Support System (BLSS). In this study, we evaluated the response of photosynthetic characters of two soybean cultivars (Glycine max (L.) Merr., ‘Zhonghuang13’and ‘Heihe35’) of C _{3} plants and one maize ( Zea mays L.) of C _{4} plants, which were selected as candidates for cultivation in BLSS. Plants were cultivated in stainless steel pots equipped with the porous-tube nutrient delivery system (PTNDS) and grew under controlled environmental conditions of Lunar Palace 1 (12 h photoperiod, light intensity 500 umol m (-2) s (-1) , temperature regime 26/22 (o) C light/dark). Fertigation was performed with a standard Hoagland solution, in which pH was kept at 5.8. A gas exchange/chlorophyII fluorescence analysis was performed to determine their net photosynthesis (Pn), stomatal (g _{s}) and mesophyll (g _{m}) conductances, intercellular CO _{2} concentration (Ci), and transpiration rate (E) under different elevated CO _{2} concentration. In order to partially describe how leaf physiology responds to the elevated CO _{2}, Chl content and the activity and amount of rubisco were analyzed. This study provides a theoretical basis for the crop selection in BLSS.

  19. Leaf anatomy and subgeneric affiliations of C3 and C4 species of Suaeda (Chenopodiaceae) in North America

    International Nuclear Information System (INIS)

    Fisher, D.D.; Schenk, H.J.; Thorsch, J.A.; Ferren, W.R. Jr.

    1997-01-01

    The halophytic genus Suaeda (Chenopodiaceae) includes species with the C3 and C4 photosynthetic pathways. North American species of this genus were investigated to determine whether C3 and C4 leaf anatomy are consistent within the two sections of Suaeda, Chenopodina and Limbogermen, present on this continent. All species from section Chenopodina were found to possess C3 anatomy, whereas all species from section Limbogermen were found to be C4 species. Characteristics of leaf anatomy and chloroplast ultrastructure are similar to those reported from C3 and C4 species, respectively, from the Eastern Hemisphere. All species from section Limbogermen have the suaedoid type of leaf anatomy, characterized by differentiation of the mesophyll into palisade parenchyma and a chlorenchymatous sheath surrounding central water-storage tissue, as well as leaf carbon isotope ratios of above -20. All species from section Chenopodina have austrobassioid leaf anatomy without a chlorenchymatous sheath and leaf carbon isotope ratio values of below -20. According to our literature review, the photosynthetic pathway has now been reported for about half (44) of the Suaeda species worldwide. The C3 and C4 photosynthetic syndromes are with few exceptions distributed along sectional or subsectional lines. These findings throw new light on the infrageneric taxonomy of this genus

  20. Similarity and Scaling of Turbulent Flame Speeds for Expanding Premixed Flames of C4-C8 n -alkanes

    Science.gov (United States)

    Wu, Fujia; Saha, Abhishek; Chaudhuri, Swetaprovo; Yang, Sheng; Law, Chung K.

    2013-11-01

    We experimentally investigated the propagation speed of constant-pressure expanding flames in near isotropic turbulence using a dual-chamber, fan-stirred vessel. The motivation is to test whether the fuel similarity concept among C4-C8 n-alkanes on laminar flames also holds for turbulent flames. Previously it was found that the laminar flame speed and Markstein length are almost identical for C4-C8 n-alkanes. If this fuel similarity concept can also be shown for turbulent flames, it will suggest a canonical flame structure for large hydrocarbon fuels, i . e . , large fuels always decompose to small C0-C4 fuel fragments before being oxidized, and would significantly simplify the description of the flames. Preliminary results show that in the flamelet and thin-reaction zone, turbulent flame speeds of C4-C8 n-alkanes are indeed largely similar at various conditions, thereby suggesting the fuel similarity for turbulent flames. In addition, it is found that the normalized turbulent flame speed also approximately scales with the square root of an appropriately-defined Reynolds number recently found for C0-C4 fuels. This work was supported by the AFOSR under the technical monitoring of Dr. Chiping Li.

  1. Introduction to Artificial Neural Networks

    DEFF Research Database (Denmark)

    Larsen, Jan

    1999-01-01

    The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks.......The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks....

  2. Criminal Aspects of Artificial Abortion

    OpenAIRE

    Hartmanová, Leona

    2016-01-01

    Criminal Aspects of Artificial Abortion This diploma thesis deals with the issue of artificial abortion, especially its criminal aspects. Legal aspects are not the most important aspects of artificial abortion. Social, ethical or ideological aspects are of the same importance but this diploma thesis cannot analyse all of them. The main issue with artificial abortion is whether it is possible to force a pregnant woman to carry a child and give birth to a child when she cannot or does not want ...

  3. Molecular and vibrational structure of the extracellular bacterial signal compound N-butyryl-homoserine lactone (C4-HSL)

    DEFF Research Database (Denmark)

    Bak, Jimmy; Spanget-Larsen, Jens

    2009-01-01

    The molecular and vibrational structure of the title compound (C4-HSL) was studied by experimental and theoretical methods. The infrared (IR) absorption spectrum was measured in the solid state and in CCl4 suspension. The observed absorption bands were compared with transitions obtained with B3LYP....../cc-pVTZ density functional theory (DFT) calculations. Two stable molecular conformations were predicted, corresponding to an endo- and an exo-conformer with similar energies. Intermolecular amide-amide hydrogen bonding in the crystal state was approximated by a simple cluster model, leading to excellent agreement...... with the observed solid state IR spectrum. Due to the low solubility of C4-HSL in common solvents for IR spectroscopy, such as CS2 and CCl4, a liquid solution spectrum of pure, monomeric C4-HSL was not obtained. However, absorbance peaks observed in oversaturated CCl4 solution could be assigned to distinct...

  4. Artificial Intelligence and Information Retrieval.

    Science.gov (United States)

    Teodorescu, Ioana

    1987-01-01

    Compares artificial intelligence and information retrieval paradigms for natural language understanding, reviews progress to date, and outlines the applicability of artificial intelligence to question answering systems. A list of principal artificial intelligence software for database front end systems is appended. (CLB)

  5. Artificial Intelligence techniques for big data analysis

    OpenAIRE

    Aditya Khatri

    2017-01-01

    During my stay in Salamanca (Spain), I was fortunate enough to participate in the BISITE Research Group of the University of Salamanca. The University of Salamanca is the oldest university in Spain and in 2018 it celebrates its 8th centenary. As a computer science researcher, I participated in one of the many international projects that the research group has active, especially in big data analysis using Artificial Intelligence (AI) techniques. AI is one of BISITE's main lines of rese...

  6. Association between Carbonyl Sulfide Uptake and 18Δ during Gas Exchange in C3 and C4 Leaves1[OA

    Science.gov (United States)

    Stimler, Keren; Berry, Joseph A.; Montzka, Steve A.; Yakir, Dan

    2011-01-01

    Carbonyl sulfide (COS) and C18OO exchange by leaves provide potentially powerful tracers of biosphere-atmosphere CO2 exchange, and both are assumed to depend on carbonic anhydrase (CA) activity and conductance along the diffusive pathway in leaves. We investigated these links using C3 and C4 plants, hypothesizing that the rates of COS and C18OO exchange by leaves respond in parallel to environmental and biological drivers. Using CA-deficient antisense lines of C4 and C3 plants, COS uptake was essentially eliminated and discrimination against C18OO exchange (18Δ) greatly reduced, demonstrating CA’s key role in both processes. 18Δ showed a positive linear correlation with leaf relative uptake (LRU; ratio of COS to CO2 assimilation rates, As/Ac, normalized to their respective ambient concentrations), which reflected the effects of stomatal conductance on both COS and C18OO exchange. Unexpectedly, a decoupling between As and 18Δ was observed in comparing C4 and C3 plants, with a large decrease in 18Δ but no parallel reduction in As in the former. This could be explained by C4 plants having higher COS concentrations at the CA site (maintaining high As with reduced CA) and a high phosphoenolpyruvate carboxylase/CA activity ratio (reducing 18O exchange efficiency between CO2 and water, but not As). Similar As but higher Ac in C4 versus C3 plants resulted in lower LRU values in the former (1.16 ± 0.20 and 1.82 ± 0.18 for C4 and C3, respectively). LRU was, however, relatively constant in both plant types across a wide range of conditions, except low light (<191 μmol photon m−2 s−1). PMID:21715674

  7. Association between carbonyl sulfide uptake and (18)Δ during gas exchange in C(3) and C(4) leaves.

    Science.gov (United States)

    Stimler, Keren; Berry, Joseph A; Montzka, Steve A; Yakir, Dan

    2011-09-01

    Carbonyl sulfide (COS) and C(18)OO exchange by leaves provide potentially powerful tracers of biosphere-atmosphere CO(2) exchange, and both are assumed to depend on carbonic anhydrase (CA) activity and conductance along the diffusive pathway in leaves. We investigated these links using C(3) and C(4) plants, hypothesizing that the rates of COS and C(18)OO exchange by leaves respond in parallel to environmental and biological drivers. Using CA-deficient antisense lines of C(4) and C(3) plants, COS uptake was essentially eliminated and discrimination against C(18)OO exchange ((18)Δ) greatly reduced, demonstrating CA's key role in both processes. (18)Δ showed a positive linear correlation with leaf relative uptake (LRU; ratio of COS to CO(2) assimilation rates, A(s)/A(c), normalized to their respective ambient concentrations), which reflected the effects of stomatal conductance on both COS and C(18)OO exchange. Unexpectedly, a decoupling between A(s) and (18)Δ was observed in comparing C(4) and C(3) plants, with a large decrease in (18)Δ but no parallel reduction in A(s) in the former. This could be explained by C(4) plants having higher COS concentrations at the CA site (maintaining high A(s) with reduced CA) and a high phosphoenolpyruvate carboxylase/CA activity ratio (reducing (18)O exchange efficiency between CO(2) and water, but not A(s)). Similar A(s) but higher A(c) in C(4) versus C(3) plants resulted in lower LRU values in the former (1.16 ± 0.20 and 1.82 ± 0.18 for C(4) and C(3), respectively). LRU was, however, relatively constant in both plant types across a wide range of conditions, except low light (<191 μmol photon m(-2) s(-1)).

  8. A high throughput gas exchange screen for determining rates of photorespiration or regulation of C4 activity.

    Science.gov (United States)

    Bellasio, Chandra; Burgess, Steven J; Griffiths, Howard; Hibberd, Julian M

    2014-07-01

    Large-scale research programmes seeking to characterize the C4 pathway have a requirement for a simple, high throughput screen that quantifies photorespiratory activity in C3 and C4 model systems. At present, approaches rely on model-fitting to assimilatory responses (A/C i curves, PSII quantum yield) or real-time carbon isotope discrimination, which are complicated and time-consuming. Here we present a method, and the associated theory, to determine the effectiveness of the C4 carboxylation, carbon concentration mechanism (CCM) by assessing the responsiveness of V O/V C, the ratio of RuBisCO oxygenase to carboxylase activity, upon transfer to low O2. This determination compares concurrent gas exchange and pulse-modulated chlorophyll fluorescence under ambient and low O2, using widely available equipment. Run time for the procedure can take as little as 6 minutes if plants are pre-adapted. The responsiveness of V O/V C is derived for typical C3 (tobacco, rice, wheat) and C4 (maize, Miscanthus, cleome) plants, and compared with full C3 and C4 model systems. We also undertake sensitivity analyses to determine the impact of R LIGHT (respiration in the light) and the effectiveness of the light saturating pulse used by fluorescence systems. The results show that the method can readily resolve variations in photorespiratory activity between C3 and C4 plants and could be used to rapidly screen large numbers of mutants or transformants in high throughput studies. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  9. Artificial neural networks in neurosurgery.

    Science.gov (United States)

    Azimi, Parisa; Mohammadi, Hasan Reza; Benzel, Edward C; Shahzadi, Sohrab; Azhari, Shirzad; Montazeri, Ali

    2015-03-01

    Artificial neural networks (ANNs) effectively analyze non-linear data sets. The aimed was A review of the relevant published articles that focused on the application of ANNs as a tool for assisting clinical decision-making in neurosurgery. A literature review of all full publications in English biomedical journals (1993-2013) was undertaken. The strategy included a combination of key words 'artificial neural networks', 'prognostic', 'brain', 'tumor tracking', 'head', 'tumor', 'spine', 'classification' and 'back pain' in the title and abstract of the manuscripts using the PubMed search engine. The major findings are summarized, with a focus on the application of ANNs for diagnostic and prognostic purposes. Finally, the future of ANNs in neurosurgery is explored. A total of 1093 citations were identified and screened. In all, 57 citations were found to be relevant. Of these, 50 articles were eligible for inclusion in this review. The synthesis of the data showed several applications of ANN in neurosurgery, including: (1) diagnosis and assessment of disease progression in low back pain, brain tumours and primary epilepsy; (2) enhancing clinically relevant information extraction from radiographic images, intracranial pressure processing, low back pain and real-time tumour tracking; (3) outcome prediction in epilepsy, brain metastases, lumbar spinal stenosis, lumbar disc herniation, childhood hydrocephalus, trauma mortality, and the occurrence of symptomatic cerebral vasospasm in patients with aneurysmal subarachnoid haemorrhage; (4) the use in the biomechanical assessments of spinal disease. ANNs can be effectively employed for diagnosis, prognosis and outcome prediction in neurosurgery. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  10. Influence of C4 Vegetation on 13CO2 Discrimination and Isoforcing in the Upper Midwest, United States

    Science.gov (United States)

    Chen, M.; Griffis, T. J.; Baker, J. M.; Erickson, M.; Corcoran, J.; Billmark, K.; Sargent, S.

    2009-12-01

    Agricultural crops with a C4 photosynthetic pathway rapidly expanded across North America as early as 800 A.D. Their distribution continues to expand globally as demands for food and biofuel production increase. These systems are highly productive, having a significant impact on carbon and water exchange between the land and atmosphere. Here, we investigate the relative impact of agricultural C4 vegetation on the local and regional CO2 biosphere-atmosphere discrimination and atmospheric isotopic forcing in the Upper Midwest, United States. We address three questions: 1. What is the relative importance of C3 and C4 species to the regional CO2 budget? How do these different photosynthetic pathways influence the regional biosphere atmosphere isotope discrimination? 3. To what extent do changes in C4 vegetation impact atmospheric isotopic forcing and the isotopic signature of the atmosphere? These questions are addressed using measurements obtained from the University of Minnesota tall tower (244 m) trace gas observatory (TGO) over the period 2007 to 2008 and are supported with scaled-up values of isotopic forcing based on ecosystem-scale eddy flux observations; high resolution land use data; and a land surface model (Community Land Model, CLM). We modified CLM to simulate dynamic C4 isotopic discrimination and accounted explicitly for canopy kinetic fractionation. A high resolution 59-yr (1948~2006) 3-hourly meteorological driving field (Sheffield) was used to spin up the model until it reached steady state. The locally measured half-hourly meteorological data were then used to drive the model from year 2007 to 2008.Our analyses indicate that local and regional C4 production was higher by 10% in 2007 due to increased demand for biofuel. Isotopic flux measurements from the tall tower and modeling confirm that this increase had a significant impact on the growing season 13CO2 photosynthetic discrimination, which ranged from 9.7 to 13.2‰ in 2007 and 11.2 to 14.8‰ in

  11. Utility of C4d immunostaining in the first year after pediatric and young adult heart transplantation.

    Science.gov (United States)

    Xu, Ying; Galambos, Csaba; Reyes-Múgica, Miguel; Miller, Susan A; Zeevi, Adriana; Webber, Steven A; Feingold, Brian

    2013-01-01

    C4d assessment of endomyocardial biopsies (EMBs) after heart transplantation (HTx) has been widely adopted to aid in the diagnosis of antibody-mediated rejection (AMR), yet it remains unclear whether or not to assess all patients routinely and with what frequency/duration. In this study we sought to evaluate the utility of routine C4d immunostaining in the first year after pediatric and young adult HTx. We reviewed pre-transplant alloantibody and clinical data, including serial EMB reports, on all 51 patients who received HTx at our center since we instituted routine C4d staining of all first-year EMBs. C4d was considered positive if diffuse capillary staining (≥ 2(+)) was present. Rare/focal capillary staining or absence of staining was considered negative. Twenty-six of 406 first-year EMBs (6%) were C4d(+) in 6 (12%) patients. Sixty-five percent of all C4d(+) EMBs occurred by 30 days post-transplant. Five of 6 patients had pre-transplant donor-specific antibody (DSA) ≥ 4,000 MFI. The sixth patient had neither pre-transplant anti-HLA antibodies nor a positive donor-specific cytotoxicity crossmatch (DSXM), but there was clinical concern for AMR. Among the entire cohort, 5 of 10 patients with pre-transplant DSA ≥ 4,000 MFI and/or a positive DSXM were C4d(+) compared with only 1 of 41 without (50% vs 2%; p = 0.001). In the first year after HTx, C4d(+) occurred early and only in children and young adults with pre-transplant DSA or with clinical suspicion of AMR. Although our data suggest that assessment limited to the first 90 days post-transplant in patients with pre-transplant DSA ≥ 4,000 MFI may be appropriate in the absence of clinical concern for AMR, further research is needed to determine the optimum strategy for post-transplant surveillance. Copyright © 2013 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  12. Leukotriene C4 synthase and ischemic cardiovascular disease and obstructive pulmonary disease in 13,000 individuals

    DEFF Research Database (Denmark)

    Freiberg, Jacob J; Dahl, Morten; Tybjaerg-Hansen, Anne

    2009-01-01

    Ischemic cardiovascular disease and obstructive pulmonary disease involve inflammation. Leukotrienes may be important pro-inflammatory mediators. We tested the hypothesis that the (-1072)G > A and (-444)A > C promoter polymorphisms of leukotriene C4 synthase confer risk of transient ischemic attack...... (TIA), ischemic stroke, ischemic heart disease (IHD), asthma, and chronic obstructive pulmonary disease (COPD). We genotyped individuals from the Danish general population, the Copenhagen City Heart Study, and Danish patients with IHD/coronary atherosclerosis, the Copenhagen Ischemic Heart Disease...... with risk of asthma or COPD. Leukotriene C4 synthase promoter genotypes influence risk of TIA and ischemic stroke, but not risk of IHD/coronary atherosclerosis, asthma, or COPD....

  13. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction....... It reviews calibration procedures, outlines the computational algorithms, and summarizes examplary applications. Four different platforms for BD and DPD simulations are presented that differ in their focus, features, and complexity....

  14. Wide Band Artificial Pulsar

    Science.gov (United States)

    Parsons, Zackary

    2017-01-01

    The Wide Band Artificial Pulsar (WBAP) is an instrument verification device designed and built by the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virgina. The site currently operates the Green Bank Ultimate Pulsar Processing Instrument (GUPPI) and the Versatile Green Bank Astronomical Spectrometer (VEGAS) digital backends for their radio telescopes. The commissioning and continued support for these sophisticated backends has demonstrated a need for a device capable of producing an accurate artificial pulsar signal. The WBAP is designed to provide a very close approximation to an actual pulsar signal. This presentation is intended to provide an overview of the current hardware and software implementations and to also share the current results from testing using the WBAP.

  15. Artificial structures on Mars

    Science.gov (United States)

    Van Flandern, T.

    2002-05-01

    Approximately 70,000 images of the surface of Mars at a resolution of up to 1.4 meters per pixel, taken by the Mars Global Surveyor spacecraft, are now in public archives. Approximately 1% of those images show features that can be broadly described as `special shapes', `tracks, trails, and possible vegetation', `spots, stripes, and tubes', `artistic imagery', and `patterns and symbols'. Rather than optical illusions and tricks of light and shadow, most of these have the character that, if photographed on Earth, no one would doubt that they were the products of large biology and intelligence. In a few cases, relationships, context, and fulfillment of a priori predictions provide objective evidence of artificiality that is exempt from the influence of experimenter biases. Only controlled test results can be trusted because biases are strong and operate both for and against artificiality.

  16. Essentials of artificial intelligence

    CERN Document Server

    Ginsberg, Matt

    1993-01-01

    Since its publication, Essentials of Artificial Intelligence has beenadopted at numerous universities and colleges offering introductory AIcourses at the graduate and undergraduate levels. Based on the author'scourse at Stanford University, the book is an integrated, cohesiveintroduction to the field. The author has a fresh, entertaining writingstyle that combines clear presentations with humor and AI anecdotes. At thesame time, as an active AI researcher, he presents the materialauthoritatively and with insight that reflects a contemporary, first hand

  17. Intelligence in Artificial Intelligence

    OpenAIRE

    Datta, Shoumen Palit Austin

    2016-01-01

    The elusive quest for intelligence in artificial intelligence prompts us to consider that instituting human-level intelligence in systems may be (still) in the realm of utopia. In about a quarter century, we have witnessed the winter of AI (1990) being transformed and transported to the zenith of tabloid fodder about AI (2015). The discussion at hand is about the elements that constitute the canonical idea of intelligence. The delivery of intelligence as a pay-per-use-service, popping out of ...

  18. Intelligence, Artificial and Otherwise

    OpenAIRE

    Chace, William M.

    1984-01-01

    I rise now to speak with the assumption that all of you know very well what I am going to say. I am the humanist here, the professor of English. We humanists, when asked to speak on questions of science and technology, are notorious for offering an embarrassed and ignorant respect toward those matters, a respect, however, which can all too quickly degenerate into insolent condescension. Face to face with the reality of computer technology, say, or with "artificial intelligence," we humanists ...

  19. Impacts of Artificial Intelligence

    OpenAIRE

    Trappl, R.

    1986-01-01

    This book, which is intended to serve as the first stage in an iterative process of detecting, predicting, and assessing the impacts of Artificial Intelligence opens with a short "one-hour course" in AI, which is intended to provide a nontechnical informative introduction to the material which follows. Next comes an overview chapter which is based on an extensive literature search, the position papers, and discussions. The next section of the book contains position papers whose richness...

  20. Ethical Artificial Intelligence

    OpenAIRE

    Hibbard, Bill

    2014-01-01

    This book-length article combines several peer reviewed papers and new material to analyze the issues of ethical artificial intelligence (AI). The behavior of future AI systems can be described by mathematical equations, which are adapted to analyze possible unintended AI behaviors and ways that AI designs can avoid them. This article makes the case for utility-maximizing agents and for avoiding infinite sets in agent definitions. It shows how to avoid agent self-delusion using model-based ut...

  1. Artificial neural network modelling

    CERN Document Server

    Samarasinghe, Sandhya

    2016-01-01

    This book covers theoretical aspects as well as recent innovative applications of Artificial Neural networks (ANNs) in natural, environmental, biological, social, industrial and automated systems. It presents recent results of ANNs in modelling small, large and complex systems under three categories, namely, 1) Networks, Structure Optimisation, Robustness and Stochasticity 2) Advances in Modelling Biological and Environmental Systems and 3) Advances in Modelling Social and Economic Systems. The book aims at serving undergraduates, postgraduates and researchers in ANN computational modelling. .

  2. Modeling artificial leaf

    OpenAIRE

    Raucci, Umberto

    2016-01-01

    The development of efficient artificial leaves relies on the subtle combination of the electronic structure of molecular assemblies able to absorbing sunlight, converting light energy into electrochemical potential energy and finally transducing it into chemical accessible energy. The electronical design of these charge transfer molecular machine is crucial to build up a complex supramolecular architecture for the light energy conversion. The theoretical computational approach represent...

  3. Artificial perception and consciousness

    Science.gov (United States)

    Caulfield, H. John; Johnson, John L.

    2000-06-01

    Perception has both unconscious and conscious aspects. In all cases, however, what we perceive is a model of reality. By brain construction through evolution, we divide the world into two parts--our body and the outside world. But the process is the same in both cases. We perceive a construct usually governed by sensed data but always involving memory, goals, fears, expectations, etc. As a first step toward Artificial Perception in man-made systems, we examine perception in general here.

  4. Artificial sweetener; Jinko kanmiryo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-08-01

    The patents related to the artificial sweetener that it is introduced to the public in 3 years from 1996 until 1998 are 115 cases. The sugar quality which makes an oligosaccharide and sugar alcohol the subject is greatly over 28 cases of the non-sugar quality in the one by the kind as a general tendency of these patents at 73 cases in such cases as the Aspartame. The method of manufacture patent, which included new material around other peptides, the oligosaccharide and sugar alcohol isn`t inferior to 56 cases of the formation thing patent at 43 cases, and pays attention to the thing, which is many by the method of manufacture, formation. There is most improvement of the quality of sweetness with 31 cases in badness of the aftertaste which is characteristic of the artificial sweetener and so on, and much stability including the improvement in the flavor of food by the artificial sweetener, a long time and dissolution, fluid nature and productivity and improvement of the economy such as a cost are seen with effect on a purpose. (NEDO)

  5. Pindarum quisquis studet aemulari: Über die Pindarode des Horaz (C. 4.2

    Directory of Open Access Journals (Sweden)

    Kristina Tomc

    2008-12-01

    in Zusammenhang mit dem Tod womöglich von einer Metamorphose in einen Schwan spricht, ein Vorbild für C. 2.20 sind, so könnte der gleiche Abschnitt auch als indirektes Vorbild für C. 4.2 angesehen werden. Das Motiv der fleißigen Biene bei Horaz hat einen Vorgänger in der Darstellung der vorbildlichen Frau des Semonides (Fr. 7.83–93 und in Vergils fleißigen Arbeiterinnen im vierten Buch der Georgica, doch die Biene verbildlicht gewöhnlich den inspirierten Dichter, wie z. B. auch bei Kallimachos (Hymn. 2.110–12 und in Horaz’ Epistel 1.3. Schon in den Scholien zu Pindar ist das Motiv der Biene der kallimacheischen Poetik angepasst. Die Analyse der Bilder zeigt, dass sich hinter den Gegensätzen in Wirklichkeit eine Synthese versteckt und dass die Poetik des Horaz gleichzeitig pindarisch und kallimacheisch ist. Es folgt eine kürzere Vorstellung des zweiten Teils des Gedichtes und zahlreicher Polemiken im Zusammenhang mit der Rolle des Julus Antonius, der statt Horaz die pindarische Ode zu Ehren des Augustus zum Anlass seiner Wiederkehr aus Gallien schreiben sollte. Im Vergleich der Opfertiere in den letzten beiden Strophen, in den Stieren und Kühen des Julus und andererseits im zarten, mit einem weißen Fleck verschönerten Kälblein des Horaz ist erneut eine poetologische Symbolik vorhanden. Eine Allusion auf Kallimachos’ Gegensatz zwischen dem ‘fetten Opfertier’ und der ‘zierlichen Muse’ aus dem Aitienprolog (Fr. 1.23–24 Pf. ist augenscheinlich, viele Ähnlichkeiten gibt es auch zu Vergil (vor allem zu Ecl. 3.85–86. Die Schlussverse bestärken Horaz’ recusatio und bestätigen seine selbstbewusste Haltung sowohl im Verhältnis zu Pindar, als auch zu Julus Antonius und Augustus.

  6. Biomass and leaf-level gas exchange characteristics of three African savanna C4 grass species under optimum growth conditions

    NARCIS (Netherlands)

    Mantlana, K.B.; Veenendaal, E.M.; Arneth, A.; Grispen, V.; Bonyongo, C.M.; Heitkönig, I.M.A.; Lloyd, J.

    2009-01-01

    C4 savanna grass species, Digitaria eriantha, Eragrostis lehmanniana and Panicum repens, were grown under optimum growth conditions with the aim of characterizing their above- and below-ground biomass allocation and the response of their gas exchange to changes in light intensity, CO2 concentration

  7. Late pliocene-pleistocene expansion of C4 vegetation in semiarid East Asia linked to increased burning : Geology

    NARCIS (Netherlands)

    Zhou, B.; Shen, C.; Sun, W.; Bird, M.; Ma, W.; Taylor, D.; Liu, W.; Peterse, F.; Yi, W.; Zheng, H.

    2014-01-01

    Plants using the C4 photosynthetic pathway, commonly tropical and subtropical grasses, increased in abundance in East Asia during the late Cenozoic. Determining the exact timing and likely factors leading to this major vegetation change requires region-specific studies. Here variations in pyrogenic

  8. Probable C4d-negative accelerated acute antibody-mediated rejection due to non-HLA antibodies.

    Science.gov (United States)

    Niikura, Takahito; Yamamoto, Izumi; Nakada, Yasuyuki; Kamejima, Sahoko; Katsumata, Haruki; Yamakawa, Takafumi; Furuya, Maiko; Mafune, Aki; Kobayashi, Akimitsu; Tanno, Yudo; Miki, Jun; Yamada, Hiroki; Ohkido, Ichiro; Tsuboi, Nobuo; Yamamoto, Hiroyasu; Yokoo, Takashi

    2015-07-01

    We report a case of probable C4d-negative accelerated acute antibody-mediated rejection due to non-HLA antibodies. A 44 year-old male was admitted to our hospital for a kidney transplant. The donor, his wife, was an ABO minor mismatch (blood type O to A) and had Gitelman syndrome. Graft function was delayed; his serum creatinine level was 10.1 mg/dL at 3 days after transplantation. Open biopsy was performed immediately; no venous thrombosis was observed during surgery. Histology revealed moderate peritubular capillaritis and mild glomerulitis without C4d immunoreactivity. Flow cytometric crossmatching was positive, but no panel-reactive antibodies against HLA or donor-specific antibodies (DSAbs) to major histocompatibility complex class I-related chain A (MICA) were detected. Taken together, we diagnosed him with probable C4d-negative accelerated antibody-mediated rejection due to non-HLA, non-MICA antibodies, the patient was treated with steroid pulse therapy (methylprednisolone 500 mg/day for 3 days), plasma exchange, intravenous immunoglobulin (40 g/body), and rituximab (200 mg/body) were performed. Biopsy at 58 days after transplantation, at which time S-Cr levels were 1.56 mg/dL, found no evidence of rejection. This case, presented with a review of relevant literature, demonstrates that probable C4d-negative accelerated acute AMR can result from non-HLA antibodies. © 2015 Asian Pacific Society of Nephrology.

  9. Structural and metabolic transitions of C4 leaf development and differentiation defined by microscopy and quantitative proteomics in maize.

    Science.gov (United States)

    Majeran, Wojciech; Friso, Giulia; Ponnala, Lalit; Connolly, Brian; Huang, Mingshu; Reidel, Edwin; Zhang, Cankui; Asakura, Yukari; Bhuiyan, Nazmul H; Sun, Qi; Turgeon, Robert; van Wijk, Klaas J

    2010-11-01

    C(4) grasses, such as maize (Zea mays), have high photosynthetic efficiency through combined biochemical and structural adaptations. C(4) photosynthesis is established along the developmental axis of the leaf blade, leading from an undifferentiated leaf base just above the ligule into highly specialized mesophyll cells (MCs) and bundle sheath cells (BSCs) at the tip. To resolve the kinetics of maize leaf development and C(4) differentiation and to obtain a systems-level understanding of maize leaf formation, the accumulation profiles of proteomes of the leaf and the isolated BSCs with their vascular bundle along the developmental gradient were determined using large-scale mass spectrometry. This was complemented by extensive qualitative and quantitative microscopy analysis of structural features (e.g., Kranz anatomy, plasmodesmata, cell wall, and organelles). More than 4300 proteins were identified and functionally annotated. Developmental protein accumulation profiles and hierarchical cluster analysis then determined the kinetics of organelle biogenesis, formation of cellular structures, metabolism, and coexpression patterns. Two main expression clusters were observed, each divided in subclusters, suggesting that a limited number of developmental regulatory networks organize concerted protein accumulation along the leaf gradient. The coexpression with BSC and MC markers provided strong candidates for further analysis of C(4) specialization, in particular transporters and biogenesis factors. Based on the integrated information, we describe five developmental transitions that provide a conceptual and practical template for further analysis. An online protein expression viewer is provided through the Plant Proteome Database.

  10. Estimation of canopy nitrogen concentration across C3 and C4 grasslands using WorldView-2 multispectral data

    CSIR Research Space (South Africa)

    Adjorlolo, C

    2014-05-01

    Full Text Available This paper assesses the potential of multispectral data attained using WorldView-2 (WV2) satellite to estimate and map the variability in canopy nitrogen (N) concentration across C3 and C4 grasslands. The WV2 satellite image was acquired...

  11. 40 CFR 721.10103 - Naphtha (Fischer-Tropsch), C4-11-alkane, branched and linear.

    Science.gov (United States)

    2010-07-01

    ...-alkane, branched and linear. 721.10103 Section 721.10103 Protection of Environment ENVIRONMENTAL..., branched and linear. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as naphtha (fischer-tropsch), C4-11-alkane, branched and linear (PMN P-04-235; CAS No...

  12. Improved analysis of C4 and C3 photosynthesis via refined in vitro assays of their carbon fixation biochemistry

    Science.gov (United States)

    Sharwood, Robert E.; Sonawane, Balasaheb V.; Ghannoum, Oula; Whitney, Spencer M.

    2016-01-01

    Plants operating C3 and C4 photosynthetic pathways exhibit differences in leaf anatomy and photosynthetic carbon fixation biochemistry. Fully understanding this underpinning biochemical variation is requisite to identifying solutions for improving photosynthetic efficiency and growth. Here we refine assay methods for accurately measuring the carboxylase and decarboxylase activities in C3 and C4 plant soluble protein. We show that differences in plant extract preparation and assay conditions are required to measure NADP-malic enzyme and phosphoenolpyruvate carboxylase (pH 8, Mg2+, 22 °C) and phosphoenolpyruvate carboxykinase (pH 7, >2mM Mn2+, no Mg2+) maximal activities accurately. We validate how the omission of MgCl2 during leaf protein extraction, lengthy (>1min) centrifugation times, and the use of non-pure ribulose-1,5-bisphosphate (RuBP) significantly underestimate Rubisco activation status. We show how Rubisco activation status varies with leaf ontogeny and is generally lower in mature C4 monocot leaves (45–60% activation) relative to C3 monocots (55–90% activation). Consistent with their >3-fold lower Rubisco contents, full Rubisco activation in soluble protein from C4 leaves (<5min) was faster than in C3 plant samples (<10min), with addition of Rubisco activase not required for full activation. We conclude that Rubisco inactivation in illuminated leaves primarily stems from RuBP binding to non-carbamylated enzyme, a state readily reversible by dilution during cellular protein extraction. PMID:27122573

  13. Atmospheric chemistry of 4:2 fluorotelomer alcohol (n-C4F9CH2CH2OH)

    DEFF Research Database (Denmark)

    Andersen, Mads Peter Sulbæk; Nielsen, Ole John; Hurley, M. D.

    2005-01-01

    Smog chamber/FTIR techniques were used to study the Cl atom initiated oxidation of 4:2 fluorotelomer alcohol (C4F9CH2CH2OH, 4:2 FTOH) in the presence of NOx in 700 Torr of N-2/O-2 diluent at 296 K. Chemical activation effects play an important role in the atmospheric chemistry of the peroxy...

  14. Molecular analysis of the murine C4b-binding protein gene. Chromosome assignment and partial gene organization

    DEFF Research Database (Denmark)

    Barum, Scott B; Kristensen, Torsten; Chaplin, David D

    1989-01-01

    . Only the latter half of the second SCR was present on the clone, and it was encoded by a single exon, demonstrating that murine C4BP has a split SCR at the genomic level. Structural mapping of this portion of the gene demonstrates that the region extending from the second half of the second SCR through...

  15. Regulation of pyruvate orthophosphate dikinase gene expression in C3 plants as compared to that in C4 plants

    International Nuclear Information System (INIS)

    Aoyagi, K.

    1985-01-01

    Pyruvate orthophosphate dikinase (PPDK) was found to be more widely distributed in both leaves and seeds of C 3 and C 4 plants than previously realized. Physicochemical and enzymic properties appear to be strongly conserved over this distribution. In wheat, a C 3 plant, both in seeds and leaves, the amount of PPDK protein is developmentally regulated. In seeds the enzyme level is determined by the level of PPDK mRNA. The role of PPDK seems to be providing phosphoenolpyruvate as a substrate for amino acid interconversions during development. In leaves, the PPDK protein level increased with development. PPDK is present in chloroplasts also in C 3 plants. In maize, a C 4 plant, PPDK is not limited to mesophyll cells but also is present in bundle sheath cells, kernels and other tissues. In the leaf, the appearance and accumulation of PPDK is well coordinated with other enzymes of carbon metabolism. In maize callus, a heterotrophic type PPDK is synthesized independently in light and is active in the dark. Shoot formation and establishment of autotrophy enhances the accumulation of the leaf-type PPDK and leaf-type isozymes of phosphoenolpyruvate carboxylase and NADP-malic enzyme. Ultrastructural changes and 14 C uptake patterns during regeneration of leaves from callus indicate that cell differentiation and Kranz anatomy are essential for the functional C 4 photosynthesis as well as for coordinated expression of enzymes involved in the C 4 pathway

  16. Atomic structure determination of InSb(100)c(4x4) and c(8x2)phases by X-ray photoelectron diffraction

    International Nuclear Information System (INIS)

    Carvalho, V.E. de; Soares, E.A.; Magalhaes, M.R.P.; Paniago, R.; Siervo, A. de; Landers, R.

    2004-01-01

    Full text: The (100) surfaces of III-V compound semiconductors exhibit a variety of surface reconstructions that have attracted a lot of attention because of their importance in both homo epitaxial and heteroepitaxial growth. In the special case of the narrow bandgap InSb compound semiconductor its potential application in high-speed electronic and optoelectronic devices has encourage many studies of its (100) surface atomic structure. Among the reconstructions presented by the InSb(100) surface two of them have received more attention, that is, the observed well-ordered In-rich c(8x2) and Sb terminated c(4x4) surfaces. The c(8x2) structure can be obtained by exposing the surface to low energy ion bombardment and annealing, whereas the c(4x4) structure involves the chemisorption of Sb onto an already Sb-terminated surface. These two structures have been studied mainly by scanning tunneling microscopy (STM) and surface X-ray diffraction (SXRD) techniques and all the proposed models are based on the occurrence of group III (and/or V) blocks of dimmers occupying sites on the top or at subsurface layer. However, there are still difficulties in determining either the exact number of atoms in each dimmer or the number of dimmers in each block. With the goal of getting a better structure determination of the InSb(100) surface phases a photoelectron diffraction experiment (XPD) was carried out at LNLS where synchrotron and Al-K α radiations have been used. In the present work, the experimental and preliminary results of structure determination for both In Sn(100)c(8x2) and InSb(100)c(4x4) phases will be presented and discussed. (author)

  17. Characterization and expression patterns of key C4photosynthetic pathway genes in bread wheat (Triticum aestivum L.) under field conditions.

    Science.gov (United States)

    Bachir, Daoura Goudia; Saeed, Iqbal; Song, Quanhao; Linn, Tay Zar; Chen, Liang; Hu, Yin-Gang

    2017-06-01

    Wheat is a C 3 plant with relatively low photosynthetic efficiency and is a potential target for C 4 photosynthetic pathway engineering. Here we reported the characterization of four key C 4 pathway genes and assessed their expression patterns and enzymatic activities at three growth stages in flag leaves of 59 bread wheat genotypes. The C 4 -like genes homologous to PEPC, NADP-ME, MDH, and PPDK in maize were identified in the A, B, and D sub-genomes of bread wheat, located on the long arms of chromosomes 3 and 5 (TaPEPC), short arms of chromosomes 1 and 3 (TaNADP-ME), long arms of chromosomes 1 and 7 (TaMDH), and long arms of chromosome 1 (TaPPDK), respectively. All the four C 4 -like genes were expressed in the flag leaves at the three growth stages with considerable variations among the 59 bread wheat genotypes. Significant differences were observed between the photosynthesis rates (A) of wheat genotypes with higher expressions of TaPEPC_5, TaNADP-ME_1, and TaMDH_7 at heading and middle grain-filling stages and those with intermediate and low expressions. Our results also indicated that the four C 4 enzymes showed activity in the flag leaves and were obviously different among the 59 wheat genotypes. The activities of PEPcase and PPDK decreased at anthesis and slightly increased at grain-filling stage, while NADP-ME and MDH exhibited a decreasing trend at the three stages. The results of the current study could be very valuable and useful for wheat researchers in improving photosynthetic capacity of wheat. Copyright © 2017 Elsevier GmbH. All rights reserved.

  18. Estimating photosynthesis and concurrent export rates in C3 and C4 species at ambient and elevated CO2

    International Nuclear Information System (INIS)

    Grodzinski, B.; Jiao, J.; Leonardos, E.D.

    1998-01-01

    The ability of 21 C3 and C4 monocot and dicot species to rapidly export newly fixed C in the light at both ambient and enriched CO2 levels was compared. Photosynthesis and concurrent export rates were estimated during isotopic equilibrium of the transport sugars using a steady-state 14CO2-labeling procedure. At ambient CO2 photosynthesis and export rates for C3 species were 5 to 15 and 1 to 10 micromole C m-2 s-1, respectively, and 20 to 30 and 15 to 22 micromole C m-2 s-1, respectively, for C4 species. A linear regression plot of export on photosynthesis rate of all species had a correlation coefficient of 0.87. When concurrent export was expressed as a percentage of photosynthesis, several C3 dicots that produced transport sugars other than Suc had high efflux rates relative to photosynthesis, comparable to those of C4 species. At high CO2 photosynthetic and export rates were only slightly altered in C4 species, and photosynthesis increased but export rates did not in all C3 species. The C3 species that had high efflux rates relative to photosynthesis at ambient CO2 exported at rates comparable to those of C4 species on both an absolute basis and as a percentage of photosynthesis. At ambient CO2 there were strong linear relationships between photosynthesis, sugar synthesis, and concurrent export. However, at high CO2 the relationships between photosynthesis and export rate and between sugar synthesis and export rate were not as strong because sugars and starch were accumulated

  19. Cinnamic acid 4-hydroxylase of sorghum [Sorghum biocolor (L.) Moench] gene SbC4H1 restricts lignin synthesis in Arabidopsis

    Science.gov (United States)

    Cinnamic acid 4-hydroxylase (C4H) is the first hydroxylase enzyme of the phenylpropanoid pathway, and its content and activity affects the lignin synthesis. In this study, we isolated a C4H gene SbC4H1 from the suppression subtractive hybridization library of brown midrib (bmr) mutants of Sorghum b...

  20. Artificial Leaf Based on Artificial Photosynthesis for Solar Fuel Production

    Science.gov (United States)

    2017-06-30

    demonstration that the conversion efficiency of CO2 to formic acid in a photo reduction reactor combining a photosensitizer and formate dehydrogenase (FDH) was...We believe that this contribution is theoretically and practically relevant because the artificial photosynthetic system developed has potential...based on the artificial photosynthesis, “artificial leaf” are proposed as for an example illustrated in Scheme 1: 1) CO2 reduction to chemical

  1. Membrane-Bound and Exosomal Metastasis-Associated C4.4A Promotes Migration by Associating with the α6β4 Integrin and MT1-MMP

    Directory of Open Access Journals (Sweden)

    Honoré Ngora

    2012-02-01

    Full Text Available Metastasis-associated C4.4A, which becomes upregulated during wound healing and, in some tumors, during tumor progression, is known to be frequently associated with hypoxia. With the function of C4.4A still unknown, we explored the impact of hypoxia on C4.4A expression and functional activity. Metastatic rat and human tumor lines upregulate C4.4A expression when cultured in the presence of CoCl2. Although hypoxia-inducible factor 1α (HIF-1α becomes upregulated concomitantly, HIF-1α did not induce C4.4A transcription. Instead, hypoxia-induced C4.4A up-regulation promoted in vivo and in vitro wound healing, where increased migration on the C4.4A ligands laminin-111 and -332 was observed after a transient period of pronounced binding. Increased migration was accompanied by C4.4A associating with α6β4, MT1-MMP1, and TACE and by laminin fragmentation. Hypoxia also promoted the release of C4.4A in exosomes and TACE-mediated C4.4A shedding. The association of C4.4A with α6β4 and MT1-MMP1 was maintained in exosomes and exosomal α6β4- and MT1-MMP1-associated C4.4A but not shed C4.4A sufficient for laminin degradation. Hypoxia-induced recruitment of α6β4 toward raft-located C4.4A, MT1-MMP, and TACE allows for a shift from adhesion to motility, which is supported by laminin degradation. These findings provide the first explanation for the C4.4A contribution to wound healing and metastasis.

  2. Structural, vibrational, DFT and optical studies of a new non-centrosymmetric hybrid material (C4H12N2)[CoBr4

    Science.gov (United States)

    Tllili, Hafsia; Walha, Sandra; Elleuch, Slim; Fares Ali, Basem; Naïli, Houcine

    2018-01-01

    The crystals of the new organic-inorganic material (C4H12N2)[CoBr4] were grown by slow evaporation technique in aqueous solution and characterized by X-ray diffraction, infrared absorption, Raman spectroscopy scattering and thermal analysis. It crystallizes at room temperature in the non-centrosymmetric space group P212121. The structure is built from isolated [CoBr4]2- anions and piperazinediium (C4H12N2)2+ cations which are connected by a network of Nsbnd H⋯Br hydrogen bonds. Theoretical calculations were performed using density functional theory with the B3LYP/LanL2DZ level for studying the molecular structure and vibrational spectra of the title compound. TDDFT calculations at the same level of theory was undertaken to investigate the electronic properties. Good adhesion is observed between calculated and experimental results. The optical study reveals that the title compound undergoes three optical absorption bands at 641, 666 and 698 nm, respectively with an energy gap estimated to 2.23 eV. Based upon this value and the non-centrosymetric character of the structure, the title compound may show several interesting applications in the field of optoelectronics.

  3. Artificial intelligence in hematology.

    Science.gov (United States)

    Zini, Gina

    2005-10-01

    Artificial intelligence (AI) is a computer based science which aims to simulate human brain faculties using a computational system. A brief history of this new science goes from the creation of the first artificial neuron in 1943 to the first artificial neural network application to genetic algorithms. The potential for a similar technology in medicine has immediately been identified by scientists and researchers. The possibility to store and process all medical knowledge has made this technology very attractive to assist or even surpass clinicians in reaching a diagnosis. Applications of AI in medicine include devices applied to clinical diagnosis in neurology and cardiopulmonary diseases, as well as the use of expert or knowledge-based systems in routine clinical use for diagnosis, therapeutic management and for prognostic evaluation. Biological applications include genome sequencing or DNA gene expression microarrays, modeling gene networks, analysis and clustering of gene expression data, pattern recognition in DNA and proteins, protein structure prediction. In the field of hematology the first devices based on AI have been applied to the routine laboratory data management. New tools concern the differential diagnosis in specific diseases such as anemias, thalassemias and leukemias, based on neural networks trained with data from peripheral blood analysis. A revolution in cancer diagnosis, including the diagnosis of hematological malignancies, has been the introduction of the first microarray based and bioinformatic approach for molecular diagnosis: a systematic approach based on the monitoring of simultaneous expression of thousands of genes using DNA microarray, independently of previous biological knowledge, analysed using AI devices. Using gene profiling, the traditional diagnostic pathways move from clinical to molecular based diagnostic systems.

  4. Did Hydrological Change Drive the Expansion of C4 Grasslands in the Siwaliks during the Late Miocene?

    Science.gov (United States)

    Pensky, J. L.; Phelps, S. R.; Uno, K. T.; Polissar, P. J.

    2014-12-01

    The vegetation change from C3 forests to C4 grasslands in India, Pakistan, and Nepal during the late Miocene has been well documented, with previous records indicating that carbon isotope changes in paleosols from Pakistan and marine sediments from the Bengal Fan correspond with a C4 plant expansion. The uplift of the Tibetan plateau, monsoon variability, late Cenozoic cooling, and hydrological changes have all been suggested as potential causes of the C4 grassland expansion, but the ultimate driver of this shift is still unknown. We investigate whether hydrological change drove the expansion of C4 grasslands in the Siwaliks around 6 Ma. We analyzed leaf wax biomarkers in Bengal Fan deep-sea core sediments deposited between 20 Ma and 0.5 Ma from ODP sites 717 and 718, where terrestrial sediments from the Ganges and Brahmaputra Rivers are deposited on the sea floor. n-Alkane concentrations and carbon and hydrogen isotope ratios were measured to characterize the vegetation shift and to determine changes in rainfall isotopic composition and continental aridity. We found that an increase of carbon isotopic ratios in the long-chain alkanes occurred very abruptly between 6.35 and 5.5 Ma, indicating a change from a C3 woodland to a C4 grass-dominated environment. This ecosystem shift was accompanied by an increase in the δD values of the plant-wax biomarkers, although the δD shift begins almost 1 My prior to the vegetation shift. Source water isotopic values were computed from the plant-wax n-alkane δD values using a landscape apparent fractionation value based upon the n-alkane carbon isotope values and reasonable vegetation end members. The source water isotope shift is larger than the lipid shift and some combination of an increase in δD of rainfall or aridity preceded the vegetation shift, and may have played a role in driving the C4 vegetation expansion. Ongoing work comparing these results to published oxygen isotope values from sedimentary archives in the

  5. Artificial mismatch hybridization

    Science.gov (United States)

    Guo, Zhen; Smith, Lloyd M.

    1998-01-01

    An improved nucleic acid hybridization process is provided which employs a modified oligonucleotide and improves the ability to discriminate a control nucleic acid target from a variant nucleic acid target containing a sequence variation. The modified probe contains at least one artificial mismatch relative to the control nucleic acid target in addition to any mismatch(es) arising from the sequence variation. The invention has direct and advantageous application to numerous existing hybridization methods, including, applications that employ, for example, the Polymerase Chain Reaction, allele-specific nucleic acid sequencing methods, and diagnostic hybridization methods.

  6. Uncertainty in artificial intelligence

    CERN Document Server

    Kanal, LN

    1986-01-01

    How to deal with uncertainty is a subject of much controversy in Artificial Intelligence. This volume brings together a wide range of perspectives on uncertainty, many of the contributors being the principal proponents in the controversy.Some of the notable issues which emerge from these papers revolve around an interval-based calculus of uncertainty, the Dempster-Shafer Theory, and probability as the best numeric model for uncertainty. There remain strong dissenting opinions not only about probability but even about the utility of any numeric method in this context.

  7. The artificial bladder.

    Science.gov (United States)

    Desgrandchamps, F; Griffith, D P

    1999-04-01

    An artificial bladder should provide adequate urine storage, allow volitional complete evacuation of urine and preserve renal function. Moreover, its structure has to be biocompatible, resistant to urinary encrustation and tolerant to bacterial infection. Various solutions have been proposed over the years to achieve these multiple requirements. However, most of these solutions and their corresponding prototypes did not advance beyond the stage of a preliminary report of experimental data. This review will bring out the 'proof of principal' in alloplastic prosthetic bladder, including type of alloplast and design concept and the recent development in tissue engineering approaches.

  8. Bayesian artificial intelligence

    CERN Document Server

    Korb, Kevin B

    2010-01-01

    Updated and expanded, Bayesian Artificial Intelligence, Second Edition provides a practical and accessible introduction to the main concepts, foundation, and applications of Bayesian networks. It focuses on both the causal discovery of networks and Bayesian inference procedures. Adopting a causal interpretation of Bayesian networks, the authors discuss the use of Bayesian networks for causal modeling. They also draw on their own applied research to illustrate various applications of the technology.New to the Second EditionNew chapter on Bayesian network classifiersNew section on object-oriente

  9. Mechanism of artificial heart

    CERN Document Server

    Yamane, Takashi

    2016-01-01

    This book first describes medical devices in relation to regenerative medicine before turning to a more specific topic: artificial heart technologies. Not only the pump mechanisms but also the bearing, motor mechanisms, and materials are described, including expert information. Design methods are described to enhance hemocompatibility: main concerns are reduction of blood cell damage and protein break, as well as prevention of blood clotting. Regulatory science from R&D to clinical trials is also discussed to verify the safety and efficacy of the devices.

  10. Artificial Enzymes, "Chemzymes"

    DEFF Research Database (Denmark)

    Bjerre, Jeannette; Rousseau, Cyril Andre Raphaël; Pedersen, Lavinia Georgeta M

    2008-01-01

    "Chemzymes", based on cyclodextrins and other molecules. Only the chemzymes that have shown enzyme-like activity that has been quantified by different methods will be mentioned. This review will summarize the work done in the field of artificial glycosidases, oxidases, epoxidases, and esterases, as well......Enzymes have fascinated scientists since their discovery and, over some decades, one aim in organic chemistry has been the creation of molecules that mimic the active sites of enzymes and promote catalysis. Nevertheless, even today, there are relatively few examples of enzyme models...

  11. Artificial intelligence in cardiology

    Directory of Open Access Journals (Sweden)

    Srishti Sharma

    2017-01-01

    Full Text Available Artificial intelligence (AI provides machines with the ability to learn and respond the way humans do and is also referred to as machine learning. The step to building an AI system is to provide the data to learn from so that it can map relations between inputs and outputs and set up parameters such as “weights”/decision boundaries to predict responses for inputs in the future. Then, the model is tested on a second data set. This article outlines the promise this analytic approach has in medicine and cardiology.

  12. Use of artificial tracers in hydrology

    International Nuclear Information System (INIS)

    1991-05-01

    The IAEA has convened an Advisory Group Meeting with the following objectives: To define the role of artificial radioactive tracers for water tracing in comparison with other non-radioactive tracers. To evaluate the real needs of artificial radioactive tracers in hydrology. To identify the fields for which artificial radioactive tracers are useful as well as those in which they can be substituted by other tracers. To discuss the strategy to be adopted to overcome the difficulties derived from the restrictions on the use of radioactive tracers in hydrology. The meeting was held at IAEA Headquarters from 19 to 22 March 1990, and was attended by 30 participants from 15 Member States. The conclusions and recommendations are that the use of artificial radioactive tracers should be restricted to cases where other tracers cannot be used or do not provide the same quality of information. Tritium, iodine-131, bromine-82, chromium-51 in the form of Cr-EDTA, technetium-99m obtained from 99 Mo-generators and gold-198 as an adsorbable tracer are, practically, the only radionuclides used for water tracing. The use of other radionuclides for this purpose does not appear to be necessary, possible and/or convenient. Refs, figs and tabs

  13. Artificial Intelligence and Economic Theories

    OpenAIRE

    Marwala, Tshilidzi; Hurwitz, Evan

    2017-01-01

    The advent of artificial intelligence has changed many disciplines such as engineering, social science and economics. Artificial intelligence is a computational technique which is inspired by natural intelligence such as the swarming of birds, the working of the brain and the pathfinding of the ants. These techniques have impact on economic theories. This book studies the impact of artificial intelligence on economic theories, a subject that has not been extensively studied. The theories that...

  14. Artificial Intelligence in Space Platforms.

    Science.gov (United States)

    1984-12-01

    computer algorithms, there still appears to be a need for Artificial Inteligence techniques in the navigation area. The reason is that navigaion, in...RD-RI32 679 ARTIFICIAL INTELLIGENCE IN SPACE PLRTFORNSMU AIR FORCE 1/𔃼 INST OF TECH WRIGHT-PRTTERSON AFB OH SCHOOL OF ENGINEERING M A WRIGHT DEC 94...i4 Preface The purpose of this study was to analyze the feasibility of implementing Artificial Intelligence techniques to increase autonomy for

  15. Parallel artificial liquid membrane extraction

    DEFF Research Database (Denmark)

    Gjelstad, Astrid; Rasmussen, Knut Einar; Parmer, Marthe Petrine

    2013-01-01

    This paper reports development of a new approach towards analytical liquid-liquid-liquid membrane extraction termed parallel artificial liquid membrane extraction. A donor plate and acceptor plate create a sandwich, in which each sample (human plasma) and acceptor solution is separated by an arti...... by an artificial liquid membrane. Parallel artificial liquid membrane extraction is a modification of hollow-fiber liquid-phase microextraction, where the hollow fibers are replaced by flat membranes in a 96-well plate format....

  16. Artificial intelligence and the future.

    Science.gov (United States)

    Clocksin, William F

    2003-08-15

    We consider some of the ideas influencing current artificial-intelligence research and outline an alternative conceptual framework that gives priority to social relationships as a key component and constructor of intelligent behaviour. The framework starts from Weizenbaum's observation that intelligence manifests itself only relative to specific social and cultural contexts. This is in contrast to a prevailing view, which sees intelligence as an abstract capability of the individual mind based on a mechanism for rational thought. The new approach is not based on the conventional idea that the mind is a rational processor of symbolic information, nor does it require the idea that thought is a kind of abstract problem solving with a semantics that is independent of its embodiment. Instead, priority is given to affective and social responses that serve to engage the whole agent in the life of the communities in which it participates. Intelligence is seen not as the deployment of capabilities for problem solving, but as constructed by the continual, ever-changing and unfinished engagement with the social group within the environment. The construction of the identity of the intelligent agent involves the appropriation or 'taking up' of positions within the conversations and narratives in which it participates. Thus, the new approach argues that the intelligent agent is shaped by the meaning ascribed to experience, by its situation in the social matrix, and by practices of self and of relationship into which intelligent life is recruited. This has implications for the technology of the future, as, for example, classic artificial intelligence models such as goal-directed problem solving are seen as special cases of narrative practices instead of as ontological foundations.

  17. Determination of the complement components C1q, C4 and C3 in serum and cerebrospinal fluid by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Dujardin, B.C.G.; Roijers, A.F.M.; Driedijk, P.C.; Out, T.A.

    1985-06-25

    Non-competitive 2-site radioimmunoassays (RIA) for the determination of the complement proteins C1q, C4 and C3 in cerebrospinal fluid (CSF) are described. The quantitative results of the RIAs were the same as those obtained by other assay methods: radial immunodiffusion and turbidimetry and, in the case of C4, the haemolytic assay. The ratios (concentration in CSF)/(concentration in serum) of the complement proteins correlated poorly with that of albumin. In contrast, the ratio of IgG was significantly correlated with that of albumin. The ratios of the complement proteins were higher than might be expected on the basis of their molecular masses. This suggests that these proteins may be synthesized within the normal central nervous system. (Auth.). 20 refs.; 3 figs.; 3 tabs.

  18. Differential carbon monoxide sensitivity of cytochrome C oxidase in the leaves of c(3) and c(4) plants.

    Science.gov (United States)

    Naik, R M; Dhage, A R; Munjal, S V; Singh, P; Desai, B B; Mehta, S L; Naik, M S

    1992-03-01

    CO sensitivity of cytochrome a(3) in the leaves of a number of C(3) and C(4) plants was monitored by the nitrate reductase assay under differing CO to O(2) ratios. All the C(3) plants were relatively insensitive to CO and required a high CO to O(2) ratio of 40 to promote significant nitrate reductase activity. However, when treated with 2 millimolar 2,4-dinitrophenol, these leaves readily responded to CO even at low CO to O(2) ratios of 10 or less. On the other hand, the leaves of all C(4) plants tested, belonging to the three subgroups, were highly sensitive to CO, even at CO to O(2) ratios of 5 or less. In these leaves, the uncoupler was without any effect, probably because the mitochondria, either from mesophyll or bundle sheath cells or both, lacked tight respiratory control.

  19. Differential Carbon Monoxide Sensitivity of Cytochrome c Oxidase in the Leaves of C3 and C4 Plants 1

    Science.gov (United States)

    Naik, Rajeev M.; Dhage, Ashok R.; Munjal, Shivaji V.; Singh, Prikshayat; Desai, Babasaheb B.; Mehta, Shanti L.; Naik, Manohar S.

    1992-01-01

    CO sensitivity of cytochrome a3 in the leaves of a number of C3 and C4 plants was monitored by the nitrate reductase assay under differing CO to O2 ratios. All the C3 plants were relatively insensitive to CO and required a high CO to O2 ratio of 40 to promote significant nitrate reductase activity. However, when treated with 2 millimolar 2,4-dinitrophenol, these leaves readily responded to CO even at low CO to O2 ratios of 10 or less. On the other hand, the leaves of all C4 plants tested, belonging to the three subgroups, were highly sensitive to CO, even at CO to O2 ratios of 5 or less. In these leaves, the uncoupler was without any effect, probably because the mitochondria, either from mesophyll or bundle sheath cells or both, lacked tight respiratory control. PMID:16668775

  20. Manganese oxide as a promoter for C2-C4 olefin production in the hydrogenation of carbon dioxide

    International Nuclear Information System (INIS)

    Kim, C.; Chen, K.; Hanson, F.V.; Oblad, A.G.; Tsai, Y.

    1986-01-01

    A number of active research and development programs have been initiated to explore the potential of CO hydrogenation process as a source of low molecular weight (C 2 -C 4 ) olefins. Metal catalysts such as Co-Mn, Ni-zeolite, Rd and Mo have been evaluated for low molecular weight olefin selectivity. The coprecipitated Fe-Mn system (Mn/Fe=9/1) was reported to be highly olefin selective. Recently, many investigators reported supporting evidence for the promotional effect of Mn for precipitated Fe catalysts. In this study, Raney Fe promoted with Mn has been evaluated for C 2 -C 4 olefin selectivity in the hydrogenation of CO relative to coprecipitated Fe-Mn catalysts. Catalyst characterization, including BET surface area, X-ray diffraction, selective chemisorption and ESCA, has been carried to provide insight into the role of manganese in both the Coprecipitated and Raney catalyst systems

  1. From reconstruction to C>4 metabolic engineering: A case study for overproduction of polyhydroxybutyrate in bioenergy grasses

    DEFF Research Database (Denmark)

    Gomes de Oliveira Dal'Molin, Cristiana; Quek, Lake-Ee; Saa, Pedro A.

    2018-01-01

    bundle sheath (B) and mesophyll (M) across the day and night cycle. The C4 leaf model was used to explore how amenable polyhydroxybutyrate (PHB) production is with these four compartments working cooperatively. A strategic pattern of metabolite conversion and exchange emerged from a systems-level network...... that has very few constraints imposed; mainly the sequential two-step carbon capture in mesophyll, then bundle sheath and photosynthesis during the day only. The building of starch reserves during the day and their mobilization during the night connects day and night metabolism. Flux simulations revealed......The compartmentalization of C4 plants increases photosynthetic efficiency, while constraining how material and energy must flow in leaf tissues. To capture this metabolic phenomenon, a generic plant metabolic reconstruction was replicated into four connected spatiotemporal compartments, namely...

  2. [Artificial neural networks in Neurosciences].

    Science.gov (United States)

    Porras Chavarino, Carmen; Salinas Martínez de Lecea, José María

    2011-11-01

    This article shows that artificial neural networks are used for confirming the relationships between physiological and cognitive changes. Specifically, we explore the influence of a decrease of neurotransmitters on the behaviour of old people in recognition tasks. This artificial neural network recognizes learned patterns. When we change the threshold of activation in some units, the artificial neural network simulates the experimental results of old people in recognition tasks. However, the main contributions of this paper are the design of an artificial neural network and its operation inspired by the nervous system and the way the inputs are coded and the process of orthogonalization of patterns.

  3. Enhancement of growth, photosynthetic performance and yield by exclusion of ambient UV components in C3 and C4 plants.

    Science.gov (United States)

    Kataria, Sunita; Guruprasad, K N; Ahuja, Sumedha; Singh, Bupinder

    2013-10-05

    A field experiment was conducted under tropical climate for assessing the effect of ambient UV-B and UV-A by exclusion of UV components on the growth, photosynthetic performance and yield of C3 (cotton, wheat) and C4 (amaranthus, sorghum) plants. The plants were grown in specially designed UV exclusion chambers, wrapped with filters that excluded UV-B (plant species responded to UV exclusion by a significant increase in plant height, leaf area, leaf biomass, total biomass accumulation and yield. Measurements of the chlorophyll, chlorophyll fluorescence parameters, gas exchange parameters and the activity of Ribulose-1,5-bisphosphate carboxylase (Rubisco) by fixation of (14)CO2 indicated a direct relationship between enhanced rate of photosynthesis and yield of the plants. Quantum yield of electron transport was enhanced by the exclusion of UV indicating better utilization of PAR assimilation and enhancement in reducing power in all the four plant species. Exclusion of UV-B in particular significantly enhanced the net photosynthetic rate, stomatal conductance and activity of Rubisco. Additional fixation of carbon due to exclusion of ambient UV-B was channeled towards yield as there was a decrease in the level of UV-B absorbing substances and an increase in soluble proteins in all the four plant species. The magnitude of the promotion in all the parameters studied was higher in dicots (cotton, amaranthus) compared to monocots (wheat, sorghum) after UV exclusion. The results indicated a suppressive action of ambient UV-B on growth and photosynthesis; dicots were more sensitive than monocots in this suppression while no great difference in sensitivity was found between C3 and C4 plants. Experiments indicated the suppressive action of ambient UV on carbon fixation and yield of C3 and C4 plants. Exclusion of solar UV-B will have agricultural benefits in both C3 and C4 plants under tropical climate. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Superoxide anion, superoxide dismutase and lipid peroxidation in the murine macrophage cell line C4M0

    Energy Technology Data Exchange (ETDEWEB)

    Imre, S.; Erdei, J.; Chihara, G.; Fachet, J.

    1985-01-01

    A remarkable increase in the production of superoxide radicals and superoxide dismutase (SOD) activity was measured in suspension of the murine macrophage cell line C4M0 treated with Lentinan (4-10 x 10/sup 3/ ..mu..g/5 x 10/sup 6/ cells). In activated macrophages the decrease of lipid peroxidation could be interpreted as a consequence of enhanced SOD activity.

  5. Performance of a C4F8O gas radiator ring imaging Cherenkov detector using multi-anode photomultiplier tubes

    International Nuclear Information System (INIS)

    Artuso, M.; Boulahouache, C.; Blusk, S.; Butt, J.; Dorjkhaidav, O.; Menaa, N.; Mountain, R.; Muramatsu, H.; Nandakumar, R.; Randrianarivony, K.; Sia, R.; Skwarnicki, T.; Stone, S.; Wang, J.C.; Zhang, K.

    2006-01-01

    We report on tests of a novel ring imaging Cherenkov (RICH) detection system consisting of a 3-m-long gaseous C 4 F 8 O radiator, a focusing mirror, and a photon detector array based on Hamamatsu multi-anode photomultiplier tubes. This system was developed to identify charged particles in the momentum range from 3 to 70GeV/c for the BTeV experiment

  6. Movie Popularity Classification based on Inherent Movie Attributes using C4.5, PART and Correlation Coefficient

    DEFF Research Database (Denmark)

    Ibnal Asad, Khalid; Ahmed, Tanvir; Rahman, Md. Saiedur

    2012-01-01

    Abundance of movie data across the internet makes it an obvious candidate for machine learning and knowledge discovery. But most researches are directed towards bi-polar classification of movie or generation of a movie recommendation system based on reviews given by viewers on various internet...... propose classification scheme of pre-release movie popularity based on inherent attributes using C4.S and PART classifier algorithm and define the relation between attributes of post release movies using correlation coefficient....

  7. Synthesis and Cytotoxicity Evaluation of C4? and C5?Modified Analogues of the ?,??Unsaturated Lactone of Pironetin

    OpenAIRE

    Huang, David S.; Wong, Henry L.; Georg, Gunda I.

    2017-01-01

    Abstract Pironetin is a natural product with potent antiproliferative activity that forms a covalent adduct with ??tubulin via conjugate addition into the natural product's ?,??unsaturated lactone. Although pironetin's ?,??unsaturated lactone is involved in its binding to tubulin, the structure?activity relationship at different positions of the lactone have not been thoroughly evaluated. For a systematic evaluation of the structure?activity relationships at the C4 and C5 positions of the ?,?...

  8. Leukotriene C4 synthase and ischemic cardiovascular disease and obstructive pulmonary disease in 13,000 individuals

    DEFF Research Database (Denmark)

    Freiberg, Jacob J; Dahl, Morten; Tybjaerg-Hansen, Anne

    2009-01-01

    Ischemic cardiovascular disease and obstructive pulmonary disease involve inflammation. Leukotrienes may be important pro-inflammatory mediators. We tested the hypothesis that the (-1072)G > A and (-444)A > C promoter polymorphisms of leukotriene C4 synthase confer risk of transient ischemic attack...... (TIA), ischemic stroke, ischemic heart disease (IHD), asthma, and chronic obstructive pulmonary disease (COPD). We genotyped individuals from the Danish general population, the Copenhagen City Heart Study, and Danish patients with IHD/coronary atherosclerosis, the Copenhagen Ischemic Heart Disease...

  9. Anisotropy and polarization in charge changing collisions of C4+ with Na(3s) and laser aligned Na(3p)

    NARCIS (Netherlands)

    Hoekstra, R; Morgenstern, R; Olson, RE

    1996-01-01

    Absolute cross sections for C3+(6-->5) emission at 465.7 nm after collisions of C4+ ions with ground state Na(3s) and laser excited aligned Na(Sp) atoms are measured over the collision energy range of 3-7 keV amu(-1). For Na(3s) polarizations are observed by measuring the linear polarization of the

  10. Artificial Blood for Dogs.

    Science.gov (United States)

    Yamada, Kana; Yokomaku, Kyoko; Kureishi, Moeka; Akiyama, Motofusa; Kihira, Kiyohito; Komatsu, Teruyuki

    2016-11-10

    There is no blood bank for pet animals. Consequently, veterinarians themselves must obtain "blood" for transfusion therapy. Among the blood components, serum albumin and red blood cells (RBCs) are particularly important to save lives. This paper reports the synthesis, structure, and properties of artificial blood for the exclusive use of dogs. First, recombinant canine serum albumin (rCSA) was produced using genetic engineering with Pichia yeast. The proteins showed identical features to those of the native CSA derived from canine plasma. Furthermore, we ascertained the crystal structure of rCSA at 3.2 Å resolution. Pure rCSA can be used widely for numerous clinical and pharmaceutical applications. Second, hemoglobin wrapped covalently with rCSA, hemoglobin-albumin cluster (Hb-rCSA 3 ), was synthesized as an artificial O 2 -carrier for the RBC substitute. This cluster possesses satisfactorily negative surface net charge (pI = 4.7), which supports enfolding of the Hb core by rCSA shells. The anti-CSA antibody recognized the rCSA exterior quantitatively. The O 2 -binding affinity was high (P 50  = 9 Torr) compared to that of the native Hb. The Hb-rCSA 3 cluster is anticipated for use as an alternative material for RBC transfusion, and as an O 2 therapeutic reagent that can be exploited in various veterinary medicine situations.

  11. KLASIFIKASI CITRA PORNO DENGAN ALGORITMA C 4.5 BERBASIS MODEL WARNA YCbCr DAN SHAPE DETECTOR

    Directory of Open Access Journals (Sweden)

    Erwin Rizki Ariyanto

    2016-06-01

    Full Text Available Konten internet dapat berupa pornografi atau jebakan pornografi dengan tujuankorban anak di bawah umur. Tahun 2010 sebesar 97% remaja pernah mengaksescontent pronografi, dimana hal terebut berpengaruh negatif terhadap perkembangananak dan remaja. Dengan demikian akses terhadap pornografi oleh anak perlu dijaga.Beberapa penelitian telah menghasilkan aplikasi pendeteksi pornografi denganberbagai metode, seperti model warna YCbCr, shape descriptor yang saling mandiri.Dalam tulisan ini kami menyajikan klasifikasi citra porno dengan menggunakanalgoritma C 4.5 dan Shape descriptor berbasis model warna YCbCr. Klasifikasi denganC 4.5 merupakan tambahan metode perbaikan pada Shape Descriptor dan model warnaYCbCr dan di harapkan dapat secara presisi mengklasifikasikan citra porno dan bukan.Hasil dari percobaan terhadap 40 citra 8 bit dengan dimensi 256X256 yang terbagimenjadi citra porno, berbikini, mug shots dan non-porno, metode di atas dapatmengklasifikasikan True Positives (TP 16, False Positives (FP 10, False Negatives (FN 4,True Negatives (TN 10 dengan akurasi 65%, error rate 35%, precision 0,615, recall 0,8 sertanilai Root Mean Squared Error (RMSE 0,59.Semakin banyak data training semakin akurathasil dari testingnya, walaupun dalam beberapa kasus metode di atas belum akurat danhanya mengenail 3 dari 10 citra mug shots atau sebesar 43%.Kata Kunci: c 4.5, shape descriptor, model warna ycbcr, citra pornografi

  12. IMPLEMENTASI DAN ANALISA HASIL DATA MINING UNTUK KLASIFIKASI SERANGAN PADA INTRUSION DETECTION SYSTEM (IDS DENGAN ALGORITMA C4.5

    Directory of Open Access Journals (Sweden)

    Izza Khaerani

    2015-10-01

    Full Text Available Intrusion Detection System (IDS merupakan sebuah kemampuan yang dimiliki oleh sebuah sistem atau perangkat untuk dapat melakukan deteksi terhadap serangan yang mungkin terjadi dalam jaringan baik lokal maupun yang terhubung dengan internet. Masalah dimulai ketika paket data yang datang sangat banyak dan harus di analisa di kemudian hari. Teknik Data Mining merupakan teknik yang tepat untuk melakukan analisa terhadap sebuah data. Beberapa penelitian telah menggunakan teknik data mining untuk mengatasi masalah serangan IDS seperti analisis frequent itemset, analisis clustering, analisis klasifikasi dan analisis asosiasi. Tujuan dari penelitian ini adalah untuk mengklasifikasikan serangan pada data-data yang diujikan dengan menggunakan metode klasifikasi dan algoritma klasifikasi C4.5. Penelitian ini menggunakan koleksi data dari KDD’99 dan memiliki 41 atribut dimana atribut ini dilakukan fitur seleksi untuk menghapus atribut yang tidak relevan dengan menggunakan teknik evolusi. Hasil yang didapatkan dari fitur seleksi ini adalah 16 atribut dengan akurasi tinggi mencapai 98,67% dari 41 atribut yang ada. Kemudian hasilnya dilakukan pemodelan dengan menggunakan algoritma C4.5 dan menghasilkan sebuah aturan untuk digunakan dalam implementasi sistem analisa klasifikasi data. Aturan yang dihasilkan dapat digunakan dalam sistem untuk mengklasifikasikan data serangan seperti dos, u2r, r2l dan probe serta aktifitas jaringan normal. Kata Kunci: Klasifikasi, Algoritma C4.5, Fitur Seleksi, Evolusi, Intrution Detection System, IDS.

  13. Mesophyll conductance in Zea mays responds transiently to CO2availability: implications for transpiration efficiency in C4crops.

    Science.gov (United States)

    Kolbe, Allison R; Cousins, Asaph B

    2018-03-01

    Mesophyll conductance (g m ) describes the movement of CO 2 from the intercellular air spaces below the stomata to the site of initial carboxylation in the mesophyll. In contrast with C 3 -g m , little is currently known about the intraspecific variation in C 4 -g m or its responsiveness to environmental stimuli. To address these questions, g m was measured on five maize (Zea mays) lines in response to CO 2 , employing three different estimates of g m . Each of the methods indicated a significant response of g m to CO 2 . Estimates of g m were similar between methods at ambient and higher CO 2 , but diverged significantly at low partial pressures of CO 2 . These differences are probably driven by incomplete chemical and isotopic equilibrium between CO 2 and bicarbonate under these conditions. Carbonic anhydrase and phosphoenolpyruvate carboxylase in vitro activity varied significantly despite similar values of g m and leaf anatomical traits. These results provide strong support for a CO 2 response of g m in Z. mays, and indicate that g m in maize is probably driven by anatomical constraints rather than by biochemical limitations. The CO 2 response of g m indicates a potential role for facilitated diffusion in C 4 -g m . These results also suggest that water-use efficiency could be enhanced in C 4 species by targeting g m . © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  14. Comparative feedstock analysis in Setaria viridis L. as a model for C4 bioenergy grasses and Panicoid crop species

    Directory of Open Access Journals (Sweden)

    Carloalberto ePetti

    2013-06-01

    Full Text Available Second generation feedstocks for bioethanol will likely include a sizable proportion of perennial C4 grasses, principally in the Panicoideae clade. The Panicoideae contain agronomically important annual grasses including Zea mays L. (maize, Sorghum bicolor (L. Moench (sorghum, and Saccharum officinarum L. (sugar cane as well as promising second generation perennial feedstocks including Miscanthus x giganteus and Panicum virgatum L. (switchgrass. The underlying complexity of these polyploid grass genomes is a major limitation for their direct manipulation and thus driving a need for rapidly cycling comparative model. Setaria viridis (green millet is a rapid cycling C4 Panicoid grass with a relatively small and sequenced diploid genome and abundant seed production. Stable, transient and protoplast transformation technologies have also been developed for S. viridis making it a potentially excellent model for other C4 bioenergy grasses. Here, the lignocellulosic feedstock composition, cellulose biosynthesis inhibitor (CBI response and saccharification dynamics of S. viridis are compared with the annual s00orghum and maize and the perennial switchgrass bioenergy crops as a baseline study into the applicability for translational research. A genome-wide systematic investigation of the cellulose synthase-A (CesA genes was performed identifying eight candidate sequences. Two-developmental stages; a metabolically active young tissue and b metabolically plateaued (mature material are examined to compare biomass performance metrics.

  15. Generative Artificial Intelligence : Philosophy and Theory of Artificial Intelligence

    NARCIS (Netherlands)

    van der Zant, Tijn; Kouw, Matthijs; Schomaker, Lambertus; Mueller, Vincent C.

    2013-01-01

    The closed systems of contemporary Artificial Intelligence do not seem to lead to intelligent machines in the near future. What is needed are open-ended systems with non-linear properties in order to create interesting properties for the scaffolding of an artificial mind. Using post-structuralistic

  16. Artificial organs: recent progress in artificial hearing and vision.

    Science.gov (United States)

    Ifukube, Tohru

    2009-01-01

    Artificial sensory organs are a prosthetic means of sending visual or auditory information to the brain by electrical stimulation of the optic or auditory nerves to assist visually impaired or hearing-impaired people. However, clinical application of artificial sensory organs, except for cochlear implants, is still a trial-and-error process. This is because how and where the information transmitted to the brain is processed is still unknown, and also because changes in brain function (plasticity) remain unknown, even though brain plasticity plays an important role in meaningful interpretation of new sensory stimuli. This article discusses some basic unresolved issues and potential solutions in the development of artificial sensory organs such as cochlear implants, brainstem implants, artificial vision, and artificial retinas.

  17. Gold as Catalyst for the Hydroarylation and Domino Hydroarylation/N1-C4 Cleavage of β-Lactam-Tethered Allenyl Indoles.

    Science.gov (United States)

    Alcaide, Benito; Almendros, Pedro; Cembellín, Sara; Martínez del Campo, Teresa

    2015-05-01

    Gold-catalyzed hydroarylation reaction of β-lactam-tethered allenyl indoles gives azeto-oxepino[4,5-b]indol-2-ones, tetrahydroazeto-azocino[3,4-b]indol-2-ones, and hexahydroazeto-azepino[3,4-b]indol-2-ones with very high levels of stereo- and regioselectivity, the 7-exo and 8-endo carbocyclization modes by attack of the indole group toward either the internal or the terminal allene carbon, respectively, being favored. Hydroarylation across the central carbon of the allene moiety has not been detected. The controlled gold-catalyzed annulations allowed the formation of fused β-lactams without harming the sensitive four-membered heterocycle. Besides, a novel gold-catalyzed domino process, namely, the allenic hydroarylation/N1-C4 β-lactam bond breakage to afford dihydro-oxepino[4,5-b]indole-4-carboxamides, has been discovered.

  18. Heavy and light beer: a carbon isotope approach to detect C(4) carbon in beers of different origins, styles, and prices.

    Science.gov (United States)

    Brooks, J Renée; Buchmann, Nina; Phillips, Sue; Ehleringer, Bruce; Evans, R David; Lott, Mike; Martinelli, Luiz A; Pockman, William T; Sandquist, Darren; Sparks, Jed P; Sperry, Lynda; Williams, Dave; Ehleringer, James R

    2002-10-23

    The carbon isotope ratios (delta(13)C) of 160 beers from around the world ranged from -27.3 to -14.9 per thousand, primarily due to variation in the percentage of C(3) or C(4) plant carbon in the final product. Thirty-one percent of beers had a carbon signature of C(3) plants (barley, rice, etc.), whereas the remaining 69% contained some C(3)-C(4) mixture (mean of mixtures, 39 +/- 11% C(4) carbon). Use of C(4) carbon (corn, cane sugar, etc.) was not confined to beers from any particular region (Pacific Rim, Mexico, Brazil, Europe, Canada, and the United States). However, the delta(13)C of European beers indicated mostly C(3) plant carbon. In contrast, U.S. and Canadian beers contained either only C(3) or C(3)-C(4) mixtures; Brazilian, Mexican, and Pacific Rim beers were mostly C(3)-C(4) mixtures. Among different lagers, U.S.-style lagers generally contained more C(4) carbon than did imported pilsners. Among different ales, those brewed by large high-production breweries contained significant proportions of C(4) carbon, while C(4) carbon was not detected in microbrewery or home-brew ales. Furthermore, inexpensive beers generally contained more C(4) carbon than expensive beers.

  19. Artificial Gravity: Effects on Bone Turnover

    Science.gov (United States)

    Heer, M.; Zwart, S /R.; Baecker, N.; Smith, S. M.

    2007-01-01

    The impact of microgravity on the human body is a significant concern for space travelers. Since mechanical loading is a main reason for bone loss, artificial gravity might be an effective countermeasure to the effects of microgravity. In a 21-day 6 head-down tilt bed rest (HDBR) pilot study carried out by NASA, USA, the utility of artificial gravity (AG) as a countermeasure to immobilization-induced bone loss was tested. Blood and urine were collected before, during, and after bed rest for bone marker determinations. Bone mineral density was determined by DXA and pQCT before and after bed rest. Urinary excretion of bone resorption markers (n-telopeptide and helical peptide) were increased from pre-bed rest, but there was no difference between the control and the AG group. The same was true for serum c-telopeptide measurements. Bone formation markers were affected by bed rest and artificial gravity. While bone-specific alkaline phosphatase tended to be lower in the AG group during bed rest (p = 0.08), PINP, another bone formation marker, was significantly lower in AG subjects than CN before and during bed rest. PINP was lower during bed rest in both groups. For comparison, artificial gravity combined with ergometric exercise was tested in a 14-day HDBR study carried out in Japan (Iwase et al. J Grav Physiol 2004). In that study, an exercise regime combined with AG was able to significantly mitigate the bed rest-induced increase in the bone resorption marker deoxypyridinoline. While further study is required to more clearly differentiate bone and muscle effects, these initial data demonstrate the potential effectiveness of short-radius, intermittent AG as a countermeasure to the bone deconditioning that occurs during bed rest and spaceflight. Future studies will need to optimize not only the AG prescription (intensity and duration), but will likely need to include the use of exercise or other combined treatments.

  20. Artificial Intelligence and brain.

    Science.gov (United States)

    Shapshak, Paul

    2018-01-01

    From the start, Kurt Godel observed that computer and brain paradigms were considered on a par by researchers and that researchers had misunderstood his theorems. He hailed with displeasure that the brain transcends computers. In this brief article, we point out that Artificial Intelligence (AI) comprises multitudes of human-made methodologies, systems, and languages, and implemented with computer technology. These advances enhance development in the electron and quantum realms. In the biological realm, animal neurons function, also utilizing electron flow, and are products of evolution. Mirror neurons are an important paradigm in neuroscience research. Moreover, the paradigm shift proposed here - 'hall of mirror neurons' - is a potentially further productive research tactic. These concepts further expand AI and brain research.

  1. Artificial Diets for Mosquitoes

    Directory of Open Access Journals (Sweden)

    Kristina K. Gonzales

    2016-12-01

    Full Text Available Mosquito-borne diseases are responsible for more than a million human deaths every year. Modern mosquito control strategies such as sterile insect technique (SIT, release of insects carrying a dominant lethal (RIDL, population replacement strategies (PR, and Wolbachia-based strategies require the rearing of large numbers of mosquitoes in culture for continuous release over an extended period of time. Anautogenous mosquitoes require essential nutrients for egg production, which they obtain through the acquisition and digestion of a protein-rich blood meal. Therefore, mosquito mass production in laboratories and other facilities relies on vertebrate blood from live animal hosts. However, vertebrate blood is expensive to acquire and hard to store for longer times especially under field conditions. This review discusses older and recent studies that were aimed at the development of artificial diets for mosquitoes in order to replace vertebrate blood.

  2. Artificially Engineered Protein Polymers.

    Science.gov (United States)

    Yang, Yun Jung; Holmberg, Angela L; Olsen, Bradley D

    2017-06-07

    Modern polymer science increasingly requires precise control over macromolecular structure and properties for engineering advanced materials and biomedical systems. The application of biological processes to design and synthesize artificial protein polymers offers a means for furthering macromolecular tunability, enabling polymers with dispersities of ∼1.0 and monomer-level sequence control. Taking inspiration from materials evolved in nature, scientists have created modular building blocks with simplified monomer sequences that replicate the function of natural systems. The corresponding protein engineering toolbox has enabled the systematic development of complex functional polymeric materials across areas as diverse as adhesives, responsive polymers, and medical materials. This review discusses the natural proteins that have inspired the development of key building blocks for protein polymer engineering and the function of these elements in material design. The prospects and progress for scalable commercialization of protein polymers are reviewed, discussing both technology needs and opportunities.

  3. Hydraulically actuated artificial muscles

    Science.gov (United States)

    Meller, M. A.; Tiwari, R.; Wajcs, K. B.; Moses, C.; Reveles, I.; Garcia, E.

    2012-04-01

    Hydraulic Artificial Muscles (HAMs) consisting of a polymer tube constrained by a nylon mesh are presented in this paper. Despite the actuation mechanism being similar to its popular counterpart, which are pneumatically actuated (PAM), HAMs have not been studied in depth. HAMs offer the advantage of compliance, large force to weight ratio, low maintenance, and low cost over traditional hydraulic cylinders. Muscle characterization for isometric and isobaric tests are discussed and compared to PAMs. A model incorporating the effect of mesh angle and friction have also been developed. In addition, differential swelling of the muscle on actuation has also been included in the model. An application of lab fabricated HAMs for a meso-scale robotic system is also presented.

  4. A programmable artificial retina

    International Nuclear Information System (INIS)

    Bernard, T.M.; Zavidovique, B.Y.; Devos, F.J.

    1993-01-01

    An artificial retina is a device that intimately associates an imager with processing facilities on a monolithic circuit. Yet, except for simple environments and applications, analog hardware will not suffice to process and compact the raw image flow from the photosensitive array. To solve this output problem, an on-chip array of bare Boolean processors with halftoning facilities might be used, providing versatility from programmability. By setting the pixel memory size to 3 b, the authors have demonstrated both the technological practicality and the computational efficiency of this programmable Boolean retina concept. Using semi-static shifting structures together with some interaction circuitry, a minimal retina Boolean processor can be built with less than 30 transistors and controlled by as few as 6 global clock signals. The successful design, integration, and test of such a 65x76 Boolean retina on a 50-mm 2 CMOS 2-μm circuit are presented

  5. Artificial resuspension studies

    International Nuclear Information System (INIS)

    Cooper, B.M.; Marchall, K.B.; Thomas, K.A.; Tracy, B.L.

    1990-01-01

    Artificial resuspension studies on a range of Taranaki and other major trial site soils were performed by use of a mechanical dust-raising apparatus. A cascade impactor was used to analyse airborne dust in terms of mass and 241 Am activities for particle sizes less than 7 μm. Plutonium and americium activities were found to be enhanced in the respirable fraction. Reported enhancement factors (defined as the ratio of activity concentration of the respirable fraction to that of the total soil) ranged from 3.7 to 32.5 for Taranaki soils with an average value of 6 appearing reasonable for general application in outer (plume) areas. Values close to unity were measured at major trial sites , One Tree and Tadje. Results of some experiments where uncontamined dust was raised by activities such as walking and driving over dusty ground are also presented. 7 refs., 9 tabs., 4 figs

  6. In Pursuit of Artificial Intelligence.

    Science.gov (United States)

    Watstein, Sarah; Kesselman, Martin

    1986-01-01

    Defines artificial intelligence and reviews current research in natural language processing, expert systems, and robotics and sensory systems. Discussion covers current commercial applications of artificial intelligence and projections of uses and limitations in library technical and public services, e.g., in cataloging and online information and…

  7. Artificial Ligaments: Promise or Panacea?

    Science.gov (United States)

    Lubell, Adele

    1987-01-01

    The Food and Drug Administration has approved a prosthetic ligament for limited use in persons with damaged anterior cruciate ligaments (ACL). This article addresses ligament repair, ACL tears, current treatment, development of the Gore-Tex artificial ligament, other artificial ligaments in process, and arguments for and against their use.…

  8. Development of artificial articular cartilage

    Indian Academy of Sciences (India)

    (UHMWPE) has been choice of orthopaedic bearing material in total joint replacement surgery since 1962, but wear of UHMWPE remains major problem facing the long term success and survival of the artificial joint. One of the main reasons of failure of the artificial joint fixation into the host bone is cellular reaction against ...

  9. Sucrose compared with artificial sweeteners

    DEFF Research Database (Denmark)

    Sørensen, Lone Brinkmann; Vasilaras, Tatjana H; Astrup, Arne

    2014-01-01

    There is a lack of appetite studies in free-living subjects supplying the habitual diet with either sucrose or artificially sweetened beverages and foods. Furthermore, the focus of artificial sweeteners has only been on the energy intake (EI) side of the energy-balance equation. The data are from...

  10. Artificial Intelligence and Language Comprehension.

    Science.gov (United States)

    National Inst. of Education (DHEW), Washington, DC. Basic Skills Group. Learning Div.

    The three papers in this volume concerning artificial intelligence and language comprehension were commissioned by the National Institute of Education to further the understanding of the cognitive processes that enable people to comprehend what they read. The first paper, "Artificial Intelligence and Language Comprehension," by Terry Winograd,…

  11. Instructional Applications of Artificial Intelligence.

    Science.gov (United States)

    Halff, Henry M.

    1986-01-01

    Surveys artificial intelligence and the development of computer-based tutors and speculates on the future of artificial intelligence in education. Includes discussion of the definitions of knowledge, expert systems (computer systems that solve tough technical problems), intelligent tutoring systems (ITS), and specific ITSs such as GUIDON, MYCIN,…

  12. Collaboration between a human group and artificial intelligence can improve prediction of multiple sclerosis course: a proof-of-principle study [version 1; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Andrea Tacchella

    2017-12-01

    Full Text Available Background: Multiple sclerosis has an extremely variable natural course. In most patients, disease starts with a relapsing-remitting (RR phase, which proceeds to a secondary progressive (SP form. The duration of the RR phase is hard to predict, and to date predictions on the rate of disease progression remain suboptimal. This limits the opportunity to tailor therapy on an individual patient's prognosis, in spite of the choice of several therapeutic options. Approaches to improve clinical decisions, such as collective intelligence of human groups and machine learning algorithms are widely investigated. Methods: Medical students and a machine learning algorithm predicted the course of disease on the basis of randomly chosen clinical records of patients that attended at the Multiple Sclerosis service of Sant'Andrea hospital in Rome. Results: A significant improvement of predictive ability was obtained when predictions were combined with a weight that depends on the consistence of human (or algorithm forecasts on a given clinical record. Conclusions: In this work we present proof-of-principle that human-machine hybrid predictions yield better prognoses than machine learning algorithms or groups of humans alone. To strengthen this preliminary result, we propose a crowdsourcing initiative to collect prognoses by physicians on an expanded set of patients.

  13. Beyond AI: Artificial Dreams Conference

    CERN Document Server

    Zackova, Eva; Kelemen, Jozef; Beyond Artificial Intelligence : The Disappearing Human-Machine Divide

    2015-01-01

    This book is an edited collection of chapters based on the papers presented at the conference “Beyond AI: Artificial Dreams” held in Pilsen in November 2012. The aim of the conference was to question deep-rooted ideas of artificial intelligence and cast critical reflection on methods standing at its foundations.  Artificial Dreams epitomize our controversial quest for non-biological intelligence, and therefore the contributors of this book tried to fully exploit such a controversy in their respective chapters, which resulted in an interdisciplinary dialogue between experts from engineering, natural sciences and humanities.   While pursuing the Artificial Dreams, it has become clear that it is still more and more difficult to draw a clear divide between human and machine. And therefore this book tries to portrait such an image of what lies beyond artificial intelligence: we can see the disappearing human-machine divide, a very important phenomenon of nowadays technological society, the phenomenon which i...

  14. Soft computing in artificial intelligence

    CERN Document Server

    Matson, Eric

    2014-01-01

    This book explores the concept of artificial intelligence based on knowledge-based algorithms. Given the current hardware and software technologies and artificial intelligence theories, we can think of how efficient to provide a solution, how best to implement a model and how successful to achieve it. This edition provides readers with the most recent progress and novel solutions in artificial intelligence. This book aims at presenting the research results and solutions of applications in relevance with artificial intelligence technologies. We propose to researchers and practitioners some methods to advance the intelligent systems and apply artificial intelligence to specific or general purpose. This book consists of 13 contributions that feature fuzzy (r, s)-minimal pre- and β-open sets, handling big coocurrence matrices, Xie-Beni-type fuzzy cluster validation, fuzzy c-regression models, combination of genetic algorithm and ant colony optimization, building expert system, fuzzy logic and neural network, ind...

  15. Altered expression of the urokinase receptor homologue, C4.4A, in invasive areas of human esophageal squamous cell carcinoma

    DEFF Research Database (Denmark)

    Hansen, L.V.; Laerum, O.D.; Illemann, M.

    2008-01-01

    . In the present study, we have therefore analyzed the expression of C4.4A in 14 esophageal squamous cell carcinomas (ESCC). Normal squamous esophageal epithelium shows a strong cell surface associated C4.4A expression in the suprabasal layers, whereas basal cells are negative. Upon transition to dysplasia...... and carcinoma in situ the expression of C4.4A is abruptly and coordinately weakened. Double immunofluorescence staining of normal and dysplastic tissue showed that C4.4A colocalizes with the epithelial cell surface marker E-cadherin in the suprabasal cells and has a complementary expression pattern compared...... to the proliferation marker Ki-67. A prominent, but frequently intracellular, C4.4A expression reappeared in tumor cells located at the invasive front and local lymph node metastases. Because C4.4A was reported previously to be a putative laminin-5 (LN5) ligand, and both proteins are expressed by invasive tumor cells...

  16. Compound-specific stable carbon isotopic signature of carbohydrate pyrolysis products from C3 and C4 plants.

    Science.gov (United States)

    González-Pérez, José A; Jiménez-Morillo, Nicasio T; de la Rosa, José M; Almendros, Gonzalo; González-Vila, Francisco J

    2016-02-01

    Pyrolysis-compound specific isotopic analysis (Py-CSIA: Py-GC-(FID)-C-IRMS) is a relatively novel technique that allows on-line quantification of stable isotope proportions in chromatographically separated products released by pyrolysis. Validation of the Py-CSIA technique is compulsory for molecular traceability in basic and applied research. In this work, commercial sucrose from C4 (sugarcane) and C3 (sugarbeet) photosystem plants and admixtures were studied using analytical pyrolysis (Py-GC/MS), bulk δ(13)C IRMS and δ(13)C Py-CSIA. Major pyrolysis compounds were furfural (F), furfural-5-hydroxymethyl (HMF) and levoglucosan (LV). Bulk and main pyrolysis compound δ(13)C (‰) values were dependent on plant origin: C3 (F, -24.65 ± 0.89; HMF, -22.07 ± 0.41‰; LV, -21.74 ± 0.17‰) and C4 (F, -14.35 ± 0.89‰; HMF, -11.22 ± 0.54‰; LV, -11.44 ± 1.26‰). Significant regressions were obtained for δ(13)C of bulk and pyrolysis compounds in C3 and C4 admixtures. Furfural (F) was found (13)C depleted with respect to bulk and HMF and LV, indicating the incorporation of the light carbon atom in position 6 of carbohydrates in the furan ring after pyrolysis. This is the first detailed report on the δ(13)C signature of major pyrolytically generated carbohydrate-derived molecules. The information provided by Py-CSIA is valuable for identifying source marker compounds of use in food science/fraud detection or in environmental research. © 2015 Society of Chemical Industry.

  17. Growth of the C4 dicot Flaveria bidentis: photosynthetic acclimation to low light through shifts in leaf anatomy and biochemistry.

    Science.gov (United States)

    Pengelly, Jasper J L; Sirault, Xavier R R; Tazoe, Youshi; Evans, John R; Furbank, Robert T; von Caemmerer, Susanne

    2010-09-01

    In C(4) plants, acclimation to growth at low irradiance by means of anatomical and biochemical changes to leaf tissue is considered to be limited by the need for a close interaction and coordination between bundle sheath and mesophyll cells. Here differences in relative growth rate (RGR), gas exchange, carbon isotope discrimination, photosynthetic enzyme activity, and leaf anatomy in the C(4) dicot Flaveria bidentis grown at a low (LI; 150 micromol quanta m(2) s(-1)) and medium (MI; 500 micromol quanta m(2) s(-1)) irradiance and with a 12 h photoperiod over 36 d were examined. RGRs measured using a 3D non-destructive imaging technique were consistently higher in MI plants. Rates of CO(2) assimilation per leaf area measured at 1500 micromol quanta m(2) s(-1) were higher for MI than LI plants but did not differ on a mass basis. LI plants had lower Rubisco and phosphoenolpyruvate carboxylase activities and chlorophyll content on a leaf area basis. Bundle sheath leakiness of CO(2) (phi) calculated from real-time carbon isotope discrimination was similar for MI and LI plants at high irradiance. phi increased at lower irradiances, but more so in MI plants, reflecting acclimation to low growth irradiance. Leaf thickness and vein density were greater in MI plants, and mesophyll surface area exposed to intercellular airspace (S(m)) and bundle sheath surface area per unit leaf area (S(b)) measured from leaf cross-sections were also both significantly greater in MI compared with LI leaves. Both mesophyll and bundle sheath conductance to CO(2) diffusion were greater in MI compared with LI plants. Despite being a C(4) species, F. bidentis is very plastic with respect to growth irradiance.

  18. Scale and the isotopic record of C4 plants in pedogenic carbonate: from the biome to the rhizospere.

    Energy Technology Data Exchange (ETDEWEB)

    Monger, Dr. H Curtis [New Mexico State University, Las Cruces; Cole, David R [ORNL; Buck, Dr. Brenda [University of Nevada, Las Vegas; Gallegos, Robert [Sant fe Water Division

    2009-01-01

    The 13C/12C ratio in pedogenic carbonate (i.e., CaCO3 formed in soil) is a significant tool for investigating C4 biomes of the past. However, the paleoecological meaning of d13C values in pedogenic carbonate can change with the scale at which one considers the data. We describe studies of modern soils, fossil soils, and vegetation change in the Chihuahuan Desert of North America and elsewhere that reveal four scales important for paleoecologic interpretations. (1) At the broadest scale, the biome scale (hundreds to millions of km2), an isotopic record interpreted as C3 vegetation replacing C4 grasslands may indicate invading C3 woody shrubs instead of expanding C3 forests (a common interpretation). (2) At the landscape scale (several tens of m2 to hundreds of km2), the accuracy of scaling up paleoclimatic interpretations to a regional level is affected by the landform containing the isotopic record. (3) At the soil-profile scale (cm2 to m2), soil profiles with multiple generations of carbonate mixed together have a lower-resolution paleoecologic record than soil profiles repeatedly buried. (4) At the rhizosphere scale (lm2 to cm2), carbonate formed on roots lack the 14 17 enrichment observed at broader scales, revealing different fractionation processes at different scales. A multi-scale approach in dealing with d13C in pedogenic carbonate will increase the accuracy of paleoecologic interpretations and understanding of soil geomorphic climatic interactions that affect boundaries between C4 and C3 vegetation.

  19. Scale and the isotopic record of C4 plants in pedogenic carbonate: from the biome to the rhizosphere

    Energy Technology Data Exchange (ETDEWEB)

    Monger, Dr. H Curtis [New Mexico State University, Las Cruces; Cole, David [Ohio State University; Buck, Dr. Brenda [University of Nevada, Las Vegas; Gallegos, Robert [Sant fe Water Division

    2009-01-01

    The 13C/12C ratio in pedogenic carbonate (i.e., CaCO3 formed in soil) is a significant tool for investigating C4 biomes of the past. However, the paleoecological meaning of d13C values in pedogenic carbonate can change with the scale at which one considers the data. We describe studies of modern soils, fossil soils, and vegetation change in the Chihuahuan Desert of North America and elsewhere that reveal four scales important for paleoecologic interpretations. (1) At the broadest scale, the biome scale (hundreds to millions of km2), an isotopic record interpreted as C3 vegetation replacing C4 grasslands may indicate invading C3 woody shrubs instead of expanding C3 forests (a common interpretation). (2) At the landscape scale (several tens of m2 to hundreds of km2), the accuracy of scaling up paleoclimatic interpretations to a regional level is affected by the landform containing the isotopic record. (3) At the soil-profile scale (cm2 to m2), soil profiles with multiple generations of carbonate mixed together have a lower-resolution paleoecologic record than soil profiles repeatedly buried. (4) At the rhizosphere scale (lm2 to cm2), carbonate formed on roots lack the 14 17 enrichment observed at broader scales, revealing different fractionation processes at different scales. A multi-scale approach in dealing with d13C in pedogenic carbonate will increase the accuracy of paleoecologic interpretations and understanding of soil geomorphic climatic interactions that affect boundaries between C4 and C3 vegetation.

  20. Artificial intelligence in nuclear power plants

    International Nuclear Information System (INIS)

    Haapanen, P.J.

    1990-01-01

    The IAEA Specialists' Meeting on Artificial Intelligence in Nuclear Power Plants was arranged in Helsink/Vantaa, Finland, on October 10-12, 1989, under auspices of the International Working Group of Nuclear Power Plant Control and Instrumentation of the International Atomic Energy Agency (IAEA/IWG NPPCI). Technical Research Centre of Finland together with Imatran Voima Oy and Teollisuuden Voima Oy answered for the practical arrangements of the meeting. 105 participants from 17 countries and 2 international organizations took part in the meeting and 58 papers were submitted for presentation. These papers gave a comprehensive picture of the recent status and further trends in applying the rapidly developing techniques of artificial intelligence and expert systems to improve the quality and safety in designing and using of nuclear power worldwide

  1. 40 CFR Table C-4 to Subpart C of... - Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods C Table C-4 to Subpart C of Part 53 Protection of Environment... Pt. 53, Subpt. C, Table C-4 Table C-4 to Subpart C of Part 53—Test Specifications for PM10, PM2.5 and...

  2. Spectral resampling based on user-defined interband correlation filter: C3 and C4 grass species classification

    CSIR Research Space (South Africa)

    Adjorlolo, C

    2013-04-01

    Full Text Available , 1996; Killick, 1963). Three zones namely, the Montane belt (1280 ? 1829 6 m), the Sub-alpine belt (1930 ? 2865 m) and the Alpine belt (2866 ? 3353 m) are defined. 7 These zones also coincide with three terraces in the Drakensberg. These include... the river 8 valley system, the foothills (also known as the Little Berg), and the summit areas, 9 respectively. The sub-alpine belt, which is composed of C3 and C4 grass species, is also 10 known as the Themeda-Festuca sub-alpine grassland (Hill, 1996...

  3. Stimulatory Effect of Chloride lons on NADP Malic Enzyme from Leaves of two C_4 Species of Cyperus

    OpenAIRE

    Takao, Murata; Osamu, Ueno; Ryu, Ohsugi; Department of Applied Physiology, National Institute of Agrobiological; Department of Applied Physiology, National Institute of Agrobiological; National Grassland Research Institute

    1989-01-01

    NADP malic enzyme (EC 1.1.1.40) from leaves of two C_4 species of Cyperus (C. rotundus and C. brevifolius var leiolepis) exihibited a low level of activity in an assay mixture that contained low concentrations of Cl^-. This low level of activity was markedly enhanced by increases in the concentration of NaCl up to 200 mM. Since the activity of NADP malic enzyme was inhibited by Na_2SO_4 and stimulated by relatively high concentration of Tris-HCl (50-100 mM, pH 7-8), the activation of the enzy...

  4. Comparison of physiological and anatomical changes of C3 (Oryza sativa [L.]) and C4 (Echinochloa crusgalli [L.]) leaves in response to drought stress

    Science.gov (United States)

    Hamim, Hamim; Banon, Sri; Dorly, Dorly

    2016-01-01

    The experiment aimed to analyse the different response of C3 (Oryza sativa L.) and C4 (Echinochloa crusgalli L.) species to drought stress based on physiological and anatomical properties. Seeds of rice (Oryza sativa) and Echinochloa (Echinochloa crusgalli) were grown in 15 cm (D) pot for 6 weeks under well-watered conditions. After 6 weeks the plants were divided into two groups, (1) well-watered which were watered daily, and (2) drought stress which were withheld from watering for 6 days. After 6 days of drought, the plants were then re-watered to analyse plant recovery. During drought period, the plants were analysed for growth, leaf relative water content (RWC), photosynthesis, and leaf anatomy. Drought stress significantly reduced leaf RWC of both species, but the reduction was bigger in rice than in Echinochloa. The maximum efficiency of photosynthesis (Fv/Fm) was decrease significantly in response to drought stress by about 48.04% in rice, while it was only 34.40% in Echinochloa. Anatomical analysis showed drought treatment tended to reduce leaf thickness in the area of bulliform cell, major- as well as intervein and xylem diameter, more in Echinochloa than in rice, suggesting that the decrease of vein and xylem diameter is among the anatomical parameters that is important to overcome from drought stress in Echinochloa. The number of chloroplast in the mesophyll cell and bundle sheath cell (BSC) was different between these two species, where in Echinochloa chloroplast was found in both mesophyll as well as BSC, while in rice it was only found in mesophyll cell, confirmed that Echinochloa is a C4 and rice is a C3 species. Interestingly, in Echinochloa, the number of chloroplast was significantly increased due to drought stress in BSC, but not in mesophyll cell. The number of starch granules also dramatically increased in response to drought in the mesophyll cells of rice and Echinochloa, and in the bundle sheath cell of Echinochloa which indicate that C3

  5. Remineralization of artificial enamel lesions by theobromine.

    Science.gov (United States)

    Amaechi, B T; Porteous, N; Ramalingam, K; Mensinkai, P K; Ccahuana Vasquez, R A; Sadeghpour, A; Nakamoto, T

    2013-01-01

    This study investigated the remineralization potential of theobromine in comparison to a standard NaF dentifrice. Three tooth blocks were produced from each of 30 teeth. Caries-like lesion was created on each block using acidified gel. A smaller block was cut from each block for baseline scanning electron microscopy imaging and electron-dispersive spectroscopy (EDS) analysis for surface Ca level. A tooth slice was cut from each lesion-bearing block for transverse microradiography (TMR) quantification of baseline mineral loss (Δz) and lesion depth (LD). Then baseline surface microhardness (SMH) of each lesion was measured. The three blocks from each tooth were assigned to three remineralizing agents: (1) artificial saliva; (2) artificial saliva with theobromine (0.0011 mol/l), and (3) NaF toothpaste slurry (0.0789 mol/l F). Remineralization was conducted using a pH cycling model with storage in artificial saliva. After a 28-day cycle, samples were analyzed using EDS, TMR, and SMH. Intragroup comparison of pre- and posttest data was performed using t tests (p theobromine (38 ± 32%) and toothpaste (29 ± 16%). With TMR (Δz/lD), theobromine and toothpaste exhibited significantly (p theobromine and toothpaste was not significantly different. With EDS, calcium deposition was significant in all groups, but not significantly different among the groups (theobromine 13 ± 8%, toothpaste 10 ± 5%, and artificial saliva 6 ± 8%). The present study demonstrated that theobromine in an apatite-forming medium can enhance the remineralization potential of the medium. Copyright © 2013 S. Karger AG, Basel.

  6. Expression of C4.4A, a structural uPAR homolog, reflects squamous epithelial differentiation in the adult mouse and during embryogenesis

    DEFF Research Database (Denmark)

    Kriegbaum, Mette Camilla; Jacobsen, Benedikte; Hald, Andreas

    2011-01-01

    by a comprehensive immunohistochemical mapping. This task was accomplished by staining paraffin-embedded tissues with a specific rabbit polyclonal anti-C4.4A antibody. In the adult mouse, C4.4A was predominantly expressed in the suprabasal layers of the squamous epithelia of the oral cavity, esophagus, non......-glandular portion of the rodent stomach, anus, vagina, cornea, and skin. This epithelial confinement was particularly evident from the abrupt termination of C4.4A expression at the squamo-columnar transition zones found at the ano-rectal and utero-vaginal junctions, for example. During mouse embryogenesis, C4.4A...

  7. Human C4orf14 interacts with the mitochondrial nucleoid and is involved in the biogenesis of the small mitochondrial ribosomal subunit.

    Science.gov (United States)

    He, J; Cooper, H M; Reyes, A; Di Re, M; Kazak, L; Wood, S R; Mao, C C; Fearnley, I M; Walker, J E; Holt, I J

    2012-07-01

    The bacterial homologue of C4orf14, YqeH, has been linked to assembly of the small ribosomal subunit. Here, recombinant C4orf14 isolated from human cells, co-purified with the small, 28S subunit of the mitochondrial ribosome and the endogenous protein co-fractionated with the 28S subunit in sucrose gradients. Gene silencing of C4orf14 specifically affected components of the small subunit, leading to decreased protein synthesis in the organelle. The GTPase of C4orf14 was critical to its interaction with the 28S subunit, as was GTP. Therefore, we propose that C4orf14, with bound GTP, binds to components of the 28S subunit facilitating its assembly, and GTP hydrolysis acts as the release mechanism. C4orf14 was also found to be associated with human mitochondrial nucleoids, and C4orf14 gene silencing caused mitochondrial DNA depletion. In vitro C4orf14 is capable of binding to DNA. The association of C4orf14 with mitochondrial translation factors and the mitochondrial nucleoid suggests that the 28S subunit is assembled at the mitochondrial nucleoid, enabling the direct transfer of messenger RNA from the nucleoid to the ribosome in the organelle.

  8. Two solid-phase recycling method for basic ionic liquid [C4mim]Ac by macroporous resin and ion exchange resin from Schisandra chinensis fruits extract.

    Science.gov (United States)

    Ma, Chun-hui; Zu, Yuan-gang; Yang, Lei; Li, Jian

    2015-01-22

    In this study, two solid-phase recycling method for basic ionic liquid (IL) 1-butyl-3-methylimidazolium acetate ([C4mim]Ac) were studied through a digestion extraction system of extracting biphenyl cyclooctene lignans from Schisandra chinensis. The RP-HPLC detection method for [C4mim]Ac was established in order to investigate the recovery efficiency of IL. The recycling method of [C4mim]Ac is divided into two steps, the first step was the separation of lignans from the IL solution containing HPD 5000 macroporous resin, the recovery efficiency and purity of [C4mim]Ac achieved were 97.8% and 67.7%, respectively. This method cannot only separate the lignans from [C4mim]Ac solution, also improve the purity of lignans, the absorption rate of lignans in [C4mim]Ac solution was found to be higher (69.2%) than that in ethanol solution (57.7%). The second step was the purification of [C4mim]Ac by the SK1B strong acid ion exchange resin, an [C4mim]Ac recovery efficiency of 55.9% and the purity higher than 90% were achieved. Additionally, [C4mim]Ac as solvent extraction of lignans from S. chinensis was optimized, the hydrolysis temperature was 90°C and the hydrolysis time was 2h. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Altered expression of the urokinase receptor homologue, C4.4A, in invasive areas of human esophageal squamous cell carcinoma

    DEFF Research Database (Denmark)

    Hansen, Line V.; Laerum, Ole D; Illemann, Martin

    2008-01-01

    . In the present study, we have therefore analyzed the expression of C4.4A in 14 esophageal squamous cell carcinomas (ESCC). Normal squamous esophageal epithelium shows a strong cell surface associated C4.4A expression in the suprabasal layers, whereas basal cells are negative. Upon transition to dysplasia...... to the proliferation marker Ki-67. A prominent, but frequently intracellular, C4.4A expression reappeared in tumor cells located at the invasive front and local lymph node metastases. Because C4.4A was reported previously to be a putative laminin-5 (LN5) ligand, and both proteins are expressed by invasive tumor cells...

  10. The artificial leaf.

    Science.gov (United States)

    Nocera, Daniel G

    2012-05-15

    To convert the energy of sunlight into chemical energy, the leaf splits water via the photosynthetic process to produce molecular oxygen and hydrogen, which is in a form of separated protons and electrons. The primary steps of natural photosynthesis involve the absorption of sunlight and its conversion into spatially separated electron-hole pairs. The holes of this wireless current are captured by the oxygen evolving complex (OEC) of photosystem II (PSII) to oxidize water to oxygen. The electrons and protons produced as a byproduct of the OEC reaction are captured by ferrodoxin of photosystem I. With the aid of ferrodoxin-NADP(+) reductase, they are used to produce hydrogen in the form of NADPH. For a synthetic material to realize the solar energy conversion function of the leaf, the light-absorbing material must capture a solar photon to generate a wireless current that is harnessed by catalysts, which drive the four electron/hole fuel-forming water-splitting reaction under benign conditions and under 1 sun (100 mW/cm(2)) illumination. This Account describes the construction of an artificial leaf comprising earth-abundant elements by interfacing a triple junction, amorphous silicon photovoltaic with hydrogen- and oxygen-evolving catalysts made from a ternary alloy (NiMoZn) and a cobalt-phosphate cluster (Co-OEC), respectively. The latter captures the structural and functional attributes of the PSII-OEC. Similar to the PSII-OEC, the Co-OEC self-assembles upon oxidation of an earth-abundant metal ion from 2+ to 3+, may operate in natural water at room temperature, and is self-healing. The Co-OEC also activates H(2)O by a proton-coupled electron transfer mechanism in which the Co-OEC is increased by four hole equivalents akin to the S-state pumping of the Kok cycle of PSII. X-ray absorption spectroscopy studies have established that the Co-OEC is a structural relative of Mn(3)CaO(4)-Mn cubane of the PSII-OEC, where Co replaces Mn and the cubane is extended in a

  11. natural or artificial diets

    Directory of Open Access Journals (Sweden)

    A. O. Meyer-Willerer

    2005-01-01

    Full Text Available Se probaron alimentos artificiales y naturales con larva de camarón (Litopenaeus vannamei cultivados en diferentes recipientes. Estos fueron ocho frascos cónicos con 15L, ocho acuarios con 50L y como grupo control, seis tanques de fibra de vidrio con 1500L; todos con agua marina fresca y filtrada. La densidad inicial en todos los recipientes fue de 70 nauplios/L. Aquellos en frascos y acuarios recibieron ya sea dieta natural o artificial. El grupo control fue cultivado con dieta natural en los tanques grandes que utilizan los laboratorios para la producción masiva de postlarvas. El principal producto de excreción de larva de camarón es el ión amonio, que es tóxico cuando está presente en concentraciones elevadas. Se determinó diariamente con el método colorimétrico del indofenol. Los resultados muestran diferencias en la concentración del ión amonio y en la sobrevivencia de larvas entre las diferentes dietas y también entre los diferentes recipientes. En aquellos con volúmenes pequeños comparados con los grandes, se presentó mayor concentración de amonio (500 a 750µg/L, en aquellos con dietas naturales, debido a que este ión sirve de fertilizante a las algas adicionadas, necesitando efectuar recambios diarios de agua posteriores al noveno día de cultivo para mantener este ión a una concentración subletal. Se obtuvo una baja cosecha de postlarvas (menor a 15% con el alimento artificial larvario, debido a la presencia de protozoarios, alimentándose con el producto comercial precipitado en el fondo de los frascos o acuarios. Los acuarios con larvas alimentadas con dieta natural también mostraron concentraciones subletales de amonio al noveno día; sin embargo, la sobrevivencia fue cuatro veces mayor que con dietas artificiales. Los tanques control con dietas naturales presentaron tasas de sobrevivencia (70 ± 5% similares a la reportada por otros laboratorios.

  12. Artificial phrenoesophageal ligament. An experimental study in dogs.

    Science.gov (United States)

    Sader, A A; Dantas, R O; Campos, A D; Evora, P R B

    2016-01-01

    This report deals with the preparation of a 'true' artificial phrenoesophageal ligament aimed at restoring effective anchoring of the esophagus to the diaphragm, keeping the esophagogastric sphincter in the abdomen. A total of 24 mongrel dogs were assigned to four groups: (i) Group I (n = 4): the esophageal diaphragm hiatus left wide open; (ii) Group II (n = 8): the anterolateral esophagus walls were attached to the diaphragm by the artificial ligament and the esophageal hiatus was left wide opened; (iii) Group III (n = 5): in addition to the use of the artificial ligament, the esophageal hiatus was narrowed with two retroesophageal stitches; (iv) Group IV (n = 7): the only procedure was the esophageal hiatus narrowing with two retroesophageal stitches. The phrenoesophagogastric connections were released, sparing the vagus nerves. Five animals of groups III and IV, which did not develop hiatal hernia, were submitted to esophageal manometry immediately before and 15 days after surgery. In group I, all animals developed huge sliding hiatal hernias. In group II, two dogs (25%) had a paraesophageal hernia between the two parts of the artificial ligament. In group III, neither sliding hiatal hernia nor paraesophageal hernia occurred. In group IV, two animals (28.6%) developed sliding esophageal hiatus hernia. Regarding esophageal manometry, postoperative significant difference between groups III and IV (P = 0.008) was observed. Thus, the artificial phrenoesophageal ligament maintained the esophagus firmly attached to the diaphragm in all animals and the esophagogastric sphincter pressure was significantly higher in this group. © 2015 International Society for Diseases of the Esophagus.

  13. Stable carbon isotope analysis of fluvial sediment fluxes over two contrasting C(4) -C(3) semi-arid vegetation transitions.

    Science.gov (United States)

    Puttock, Alan; Dungait, Jennifer A J; Bol, Roland; Dixon, Elizabeth R; Macleod, Christopher J A; Brazier, Richard E

    2012-10-30

    Globally, many drylands are experiencing the encroachment of woody vegetation into grasslands. These changes in ecosystem structure and processes can result in increased sediment and nutrient fluxes due to fluvial erosion. As these changes are often accompanied by a shift from C(4) to C(3) vegetation with characteristic δ(13) C values, stable isotope analysis provides a promising mechanism for tracing these fluxes. Input vegetation, surface sediment and fluvially eroded sediment samples were collected across two contrasting C(4) -C(3) dryland vegetation transitions in New Mexico, USA. Isotope ratio mass spectrometric analyses were performed using a Carlo Erba NA2000 analyser interfaced to a SerCon 20-22 isotope ratio mass spectrometer to determine bulk δ(13) C values. Stable isotope analyses of contemporary input vegetation and surface sediments over the monitored transitions showed significant differences (p fluvially eroded sediment from each of the sites, with no significant variation between surface sediment and eroded sediment values. The significant differences in bulk δ(13) C values between sites were dependent on vegetation input. Importantly, these values were robustly expressed in fluvially eroded sediments, suggesting that stable isotope analysis is suitable for tracing sediment fluxes. Due to the prevalent nature of these dryland vegetation transitions in the USA and globally, further development of stable isotope ratio mass spectrometry has provided a valuable tool for enhanced understanding of functional changes in these ecosystems. Copyright © 2012 John Wiley & Sons, Ltd.

  14. Interaction of leukotriene C4 and Chinese hamster lung fibroblasts (V79A03 cells). 1. Characterization of binding

    Energy Technology Data Exchange (ETDEWEB)

    Fitz, T.A.; Contois, D.F.; Liu, Y.X.; Watt, D.S.; Walden, T.L.

    1990-10-01

    A novel, specific, and potent biological action of leukotriene C4 (LTC4) was demonstrated in the Chinese Hamster lung fibroblast cell line V79A03 (V79 cells), namely the conferment of protection against subsequent irradiation. Consequently, studies were conducted to determine whether LTC4-conferred radioprotection could be attributed to a receptor-mediated phenomenon. Specific binding sites for leukotriene C4 (LTC4) were identified and characterized using intact V79 cells incubated at 4 C in the presence of serine-borate, during which time conversion of LTC4 to LTD4 or LTE4 was undetectable. Binding was maximal in a broad region between pH 6.2 and 8.8. Ca2+, Mg2+, and Na+ were not required for binding, and binding was not altered by GTP, ATP, cAMP, by leukotrienes B4, D4, or E4, or by the leukotriene end point antagonists LY 171883, FPL 55712, or Revlon 5901-5.

  15. Borrelia burgdorferi outer surface protein C (OspC) binds complement component C4b and confers bloodstream survival.

    Science.gov (United States)

    Caine, Jennifer A; Lin, Yi-Pin; Kessler, Julie R; Sato, Hiromi; Leong, John M; Coburn, Jenifer

    2017-12-01

    Borrelia burgdorferi (Bb) is the causative agent of Lyme disease in the United States, a disease that can result in carditis, and chronic and debilitating arthritis and/or neurologic symptoms if left untreated. Bb survives in the midgut of the Ixodes scapularis tick, or within tissues of immunocompetent hosts. In the early stages of infection, the bacteria are present in the bloodstream where they must resist clearance by the innate immune system of the host. We have found a novel role for outer surface protein C (OspC) from B. burgdorferi and B. garinii in interactions with the complement component C4b and bloodstream survival in vivo. Our data show that OspC inhibits the classical and lectin complement pathways and competes with complement protein C2 for C4b binding. Resistance to complement is important for maintenance of the lifecycle of Bb, enabling survival of the pathogen within the host as well as in the midgut of a feeding tick when ospC expression is induced. © 2017 John Wiley & Sons Ltd.

  16. Environmental Performance of Miscanthus, Switchgrass and Maize: Can C4 Perennials Increase the Sustainability of Biogas Production?

    Directory of Open Access Journals (Sweden)

    Andreas Kiesel

    2016-12-01

    Full Text Available Biogas is considered a promising option for complementing the fluctuating energy supply from other renewable sources. Maize is currently the dominant biogas crop, but its environmental performance is questionable. Through its replacement with high-yielding and nutrient-efficient perennial C4 grasses, the environmental impact of biogas could be considerably improved. The objective of this paper is to assess and compare the environmental performance of the biogas production and utilization of perennial miscanthus and switchgrass and annual maize. An LCA was performed using data from field trials, assessing the impact in the five categories: climate change (CC, fossil fuel depletion (FFD, terrestrial acidification (TA, freshwater eutrophication (FE and marine eutrophication (ME. A system expansion approach was adopted to include a fossil reference. All three crops showed significantly lower CC and FFD potentials than the fossil reference, but higher TA and FE potentials, with nitrogen fertilizer production and fertilizer-induced emissions identified as hot spots. Miscanthus performed best and changing the input substrate from maize to miscanthus led to average reductions of −66% CC; −74% FFD; −63% FE; −60% ME and −21% TA. These results show that perennial C4 grasses and miscanthus in particular have the potential to improve the sustainability of the biogas sector.

  17. Interpretation of Clinical Data Based on C4.5 Algorithm for the Diagnosis of Coronary Heart Disease.

    Science.gov (United States)

    Wiharto, Wiharto; Kusnanto, Hari; Herianto, Herianto

    2016-07-01

    The interpretation of clinical data for the diagnosis of coronary heart disease can be done using algorithms in data mining. Most clinical data interpretation systems for diagnosis developed using data mining algorithms with a black-box approach cannot recognize examination attribute relationships with the incidence of coronary heart disease. This study proposes a system to interpretation clinical examination results for the diagnosis of coronary heart disease based the decision tree algorithm. This system comprises several stages. First, oversampling is carried out by a combination of the synthetic minority oversampling technique (SMOTE), feature selection, and the C4.5 classification algorithm. System testing is done using k-fold cross-validation. The performance parameters are sensitivity, specificity, positive prediction value (PPV), negative prediction value (NPV) and the area under the curve (AUC). The results showed that the performance of the system has a sensitivity of 74.7%, a specificity of 93.7%, a PPV of 74.2%, an NPV of 93.7%, and an AUC of 84.2%. This study demonstrated that, by using C4.5 algorithms, data can be interpreted in the form of a decision tree, to aid the understanding of the clinician. In addition, the proposed system can provide better performance by category.

  18. Hybrid Modified K-Means with C4.5 for Intrusion Detection Systems in Multiagent Systems.

    Science.gov (United States)

    Laftah Al-Yaseen, Wathiq; Ali Othman, Zulaiha; Ahmad Nazri, Mohd Zakree

    2015-01-01

    Presently, the processing time and performance of intrusion detection systems are of great importance due to the increased speed of traffic data networks and a growing number of attacks on networks and computers. Several approaches have been proposed to address this issue, including hybridizing with several algorithms. However, this paper aims at proposing a hybrid of modified K-means with C4.5 intrusion detection system in a multiagent system (MAS-IDS). The MAS-IDS consists of three agents, namely, coordinator, analysis, and communication agent. The basic concept underpinning the utilized MAS is dividing the large captured network dataset into a number of subsets and distributing these to a number of agents depending on the data network size and core CPU availability. KDD Cup 1999 dataset is used for evaluation. The proposed hybrid modified K-means with C4.5 classification in MAS is developed in JADE platform. The results show that compared to the current methods, the MAS-IDS reduces the IDS processing time by up to 70%, while improving the detection accuracy.

  19. Systems biology and metabolic modelling unveils limitations to polyhydroxybutyrate accumulation in sugarcane leaves; lessons for C4 engineering.

    Science.gov (United States)

    McQualter, Richard B; Bellasio, Chandra; Gebbie, Leigh K; Petrasovits, Lars A; Palfreyman, Robin W; Hodson, Mark P; Plan, Manuel R; Blackman, Deborah M; Brumbley, Stevens M; Nielsen, Lars K

    2016-02-01

    In planta production of the bioplastic polyhydroxybutyrate (PHB) is one important way in which plant biotechnology can address environmental problems and emerging issues related to peak oil. However, high biomass C4 plants such as maize, switch grass and sugarcane develop adverse phenotypes including stunting, chlorosis and reduced biomass as PHB levels in leaves increase. In this study, we explore limitations to PHB accumulation in sugarcane chloroplasts using a systems biology approach, coupled with a metabolic model of C4 photosynthesis. Decreased assimilation was evident in high PHB-producing sugarcane plants, which also showed a dramatic decrease in sucrose and starch content of leaves. A subtle decrease in the C/N ratio was found which was not associated with a decrease in total protein content. An increase in amino acids used for nitrogen recapture was also observed. Based on the accumulation of substrates of ATP-dependent reactions, we hypothesized ATP starvation in bundle sheath chloroplasts. This was supported by mRNA differential expression patterns. The disruption in ATP supply in bundle sheath cells appears to be linked to the physical presence of the PHB polymer which may disrupt photosynthesis by scattering photosynthetically active radiation and/or physically disrupting thylakoid membranes. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  20. Hybrid Modified K-Means with C4.5 for Intrusion Detection Systems in Multiagent Systems

    Directory of Open Access Journals (Sweden)

    Wathiq Laftah Al-Yaseen

    2015-01-01

    Full Text Available Presently, the processing time and performance of intrusion detection systems are of great importance due to the increased speed of traffic data networks and a growing number of attacks on networks and computers. Several approaches have been proposed to address this issue, including hybridizing with several algorithms. However, this paper aims at proposing a hybrid of modified K-means with C4.5 intrusion detection system in a multiagent system (MAS-IDS. The MAS-IDS consists of three agents, namely, coordinator, analysis, and communication agent. The basic concept underpinning the utilized MAS is dividing the large captured network dataset into a number of subsets and distributing these to a number of agents depending on the data network size and core CPU availability. KDD Cup 1999 dataset is used for evaluation. The proposed hybrid modified K-means with C4.5 classification in MAS is developed in JADE platform. The results show that compared to the current methods, the MAS-IDS reduces the IDS processing time by up to 70%, while improving the detection accuracy.