WorldWideScience

Sample records for organic structure determination

  1. Structural determination of organic compounds

    International Nuclear Information System (INIS)

    Kintzinger, J.P.

    1991-01-01

    This paper reports that the current methods available in high-field NMR spectroscopy are such that the tridimensional structure determination of any rigid molecule containing only carbon and hydrogen atoms may be achieved. The connectivities between carbon-carbon, carbon-hydrogen, and hydrogen-hydrogen atoms are determined by multipulse and two-dimensional (2D) experiments. These connectivity patterns or maps allow a step-by-step reconstruction of the molecular structures. From the carbon-carbon connectivity map, the carbon framework of the molecule is obtained, whereas the carbon-hydrogen pattern allows determination of the positions of the hydrogen atoms on their corresponding carbon atoms. High-field spectrometers are then necessary to remove fortuitous degeneracy and to reduce the proton spectra to a nearly first-order one, allowing an easy measurement of the chemical shifts and the coupling constants

  2. Application of molecular spectroscopy to the determination of organic structures

    International Nuclear Information System (INIS)

    Leicknam, J.P.

    1976-01-01

    Some brief accounts are presented followed by a discussion about various physico-chemical techniques: Raman spectrometry, infrared spectrometry, resonance Raman spectrometry, conformational analysis and polarized Rayleigh diffusion. Applications of the Nuclear Magnetic Resonance to nucleotide structure in aqueous solution are described as well as some applications of neutron scattering to the study of organic structures [fr

  3. Structure Determination of Unknown Organic Liquids Using NMR and IR Spectroscopy: A General Chemistry Laboratory

    Science.gov (United States)

    Pavel, John T.; Hyde, Erin C.; Bruch, Martha D.

    2012-01-01

    This experiment introduced general chemistry students to the basic concepts of organic structures and to the power of spectroscopic methods for structure determination. Students employed a combination of IR and NMR spectroscopy to perform de novo structure determination of unknown alcohols, without being provided with a list of possible…

  4. Structure determination of organic compounds by 'electron pyrolysis'. Pt. 6

    International Nuclear Information System (INIS)

    Ege, G.; Gessner, K.; Schildknecht, H.

    1977-01-01

    By action of tritiated water on N-substituted 3-Amino-Δ 4 -thiazoline-2-ones and -2-thiones cleavage of the N-N-bond occurs with the formation of Δ 4 -thiazoline-2-ones and -2-thiones, respectively, and H 2 N-R 3 . Detection and identification of the fragments is performed by thin-layer chromatography and by comparison with authentic samples under the application of a radio-scanner. Such a fragmention is strong evidence for the five-membered ring structure. (orig.) [de

  5. Chromatin Structure and Replication Origins: Determinants Of Chromosome Replication And Nuclear Organization

    Science.gov (United States)

    Smith, Owen K.; Aladjem, Mirit I.

    2014-01-01

    The DNA replication program is, in part, determined by the epigenetic landscape that governs local chromosome architecture and directs chromosome duplication. Replication must coordinate with other biochemical processes occurring concomitantly on chromatin, such as transcription and remodeling, to insure accurate duplication of both genetic and epigenetic features and to preserve genomic stability. The importance of genome architecture and chromatin looping in coordinating cellular processes on chromatin is illustrated by two recent sets of discoveries. First, chromatin-associated proteins that are not part of the core replication machinery were shown to affect the timing of DNA replication. These chromatin-associated proteins could be working in concert, or perhaps in competition, with the transcriptional machinery and with chromatin modifiers to determine the spatial and temporal organization of replication initiation events. Second, epigenetic interactions are mediated by DNA sequences that determine chromosomal replication. In this review we summarize recent findings and current models linking spatial and temporal regulation of the replication program with epigenetic signaling. We discuss these issues in the context of the genome’s three-dimensional structure with an emphasis on events occurring during the initiation of DNA replication. PMID:24905010

  6. Body size and dispersal mode as key traits determining metacommunity structure of aquatic organisms

    NARCIS (Netherlands)

    De Bie, T.; De Meester, L.; Brendonck, L.; Martens, K.; Goddeeris, B.; Ercken, D.; Hampel, H.; Denys, L.; Vanhecke, L.; Van der Gucht, K.; Van Wichelen, J.; Vyverman, W.; Declerck, S.A.J.

    2012-01-01

    Relationships between traits of organisms and the structure of their metacommunities have so far mainly been explored with meta-analyses. We compared metacommunities of a wide variety of aquatic organism groups (12 groups, ranging from bacteria to fish) in the same set of 99 ponds to minimise biases

  7. Factors Affecting the Structural Features of Dairy Farming Organizations in Yalova: Determining the Breeding Activities

    Directory of Open Access Journals (Sweden)

    Galip BAKIR

    2014-03-01

    Full Text Available This research has been performed to determine dairy farms’ breeders’ social conditions, presence of animals, care, milk production, happiness with animal farming, problems and situation of being organized in Yalova. The data that obtained from 324 randomly chosen dairy farms around the city by the means of the survey comprised the material of research. The obtained data has been analyzed in SPSS package program by taking animal numbers, age and educational background of breeders as factors affecting the structural condition of farm. In the analysis of race distribution it was determined that breeders having primary education preferred to use crossbred animals, whereas breeders having secondary, high school and higher education tended to use culture breeds. For determining the heat in animals, breeders who have primary school education take bellowing and mounting of animals into consideration. All breeders at any education level considered the 15-18 months of age as age at fist insemination for heifers. As the age of breeders increased, contrary to education level, the ratio for 15-18 month age criterion decreased. In the farms producing less than 10 kg milk the ratio of farmers having primary school education is 68.9%. This ratio is 8.5% for high school and higher graduates. 61.2% of breeders who have middle school education level obtain 11-20 kg milk yield in their farms. While 48.6% of breeders who have less than 5 animals obtain 10 kg milk yield, as the number of animals rises, this rate declined to 23.1%. In the farms having less than 5 animals the proportion of obtaining 10-21 kg milk yield is 48.4%. As the animals numbers increased this proportion increased up to 63.5%.

  8. Determination of crystal structures by x-ray diffraction: applications to a lanthanide complex and a natural organic compound

    International Nuclear Information System (INIS)

    Miranda, J.M. de.

    1986-01-01

    The study fir determining crystal structures of the Ho (ReO sub(4)) sub(3) 4 TDTD 3 H sub(2) O complex and the natural organic compound C sub(14) H sub(16) O sub(6) by X-ray diffraction are presented. The experimental equipments are described in details. (M.C.K.)

  9. Determining Inorganic and Organic Carbon.

    Science.gov (United States)

    Koistinen, Jaana; Sjöblom, Mervi; Spilling, Kristian

    2017-11-21

    Carbon is the element which makes up the major fraction of lipids and carbohydrates, which could be used for making biofuel. It is therefore important to provide enough carbon and also follow the flow into particulate organic carbon and potential loss to dissolved organic forms of carbon. Here we present methods for determining dissolved inorganic carbon, dissolved organic carbon, and particulate organic carbon.

  10. Application of the crystalline structure determination method by X-ray diffraction to natural products and organic compounds

    International Nuclear Information System (INIS)

    Vencato, I.

    1984-01-01

    The structures of two natural compounds, a synthetic phosphate and a copper complexe were determined and the structure of another copper complex was refined. The reflection intensities were measured with a CAD-4 automatic diffractometer. The structures were solved by direct methods using either MULTAN-80 or the Patterson function and were refined by the least squares method, with a full matrix. (E.G.) [pt

  11. Determinants of capital structure.

    Science.gov (United States)

    McCue, M J; Ozcan, Y A

    1992-01-01

    This study analyzes the determinants of hospital capital structure in a new market setting that are created by the financial pressures of prospective payment and the intense price competition among hospitals. Using California data, the study found hospital system affiliation, bed size, growth rate in revenues, operating risk, and asset structure affected both short- and long-term debt borrowings. In addition, percentage of uncompensated care, profitability, and payer mix influenced short-term borrowings while market conditions and ownership affected long-term borrowings. Most significant of all is the finding that smaller hospitals tend to borrow more, possibly because they cannot generate funds internally.

  12. Determination of Three-Dimensional Morphology and Inner Structure of Second-Phase Inclusions in Metals by Non-Aqueous Solution Electrolytic and Room Temperature Organic Methods

    OpenAIRE

    Jing Guo; Keming Fang; Hanjie Guo; Yiwa Luo; Shengchao Duan; Xiao Shi; Wensheng Yang

    2018-01-01

    The secondary-phase particles in metals, particularly those composed of non-metallic materials, are often detrimental to the mechanical properties of metals; thus, it is crucial to control inclusion formation and growth. One of the challenges is determining the three-dimensional morphology and inner structures of such inclusions. In this study, a non-aqueous solution electrolytic method and a room-temperature organic technique were developed based on the principle of electrochemistry to deter...

  13. Determinants of Organic Products Consumption

    Directory of Open Access Journals (Sweden)

    Matheus Wemerson Gomes Pereira

    2015-04-01

    Full Text Available The increased environmental awareness and the growing desire for safer foods to health made the organic products category one of the most growing in the food sector. Thus, this study aimed to identify the most significant socioeconomic variables that influence the frequency of organic products consumption, and for that, it was based on a quantitative-descriptive study with a probability sample of 400 individuals, residing of the urban area of Campo Grande/MS, Brazil, responsible, alone or not, for food purchasing in family. As a tool for data collection, was used a structured questionnaire developed from socioeconomic variables and frequency of consumption of organic products. For the data analysis was performed statistical/econometric tests with the STATA 11.0 statistical software, using Multinomial Logit model (MNL, addition to verification of the explanatory variables effect on the probability of the consumption frequency levels of organic products through the Relative Risk Ratio (RRR, and was analyzed the Marginal Effect (ME exercised by the explanatory variables in each frequency level of organic products consumption. The results showed that the explanatory variables gender, education and economic class were statistically significant in the probability of an individual belong to some of the levels of consumption (rare, occasional and frequent over never having consumed organic products, being higher frequency of consumption when the consumer is female, have higher education or is of higher economic class.

  14. Structural organization of the human glucocorticoid receptor determined by one- and two-dimensional gel electrophoresis of proteolytic receptor fragments

    International Nuclear Information System (INIS)

    Smith, A.C.; Harmon, J.M.

    1987-01-01

    The structural organization of the steroid-binding protein of the IM-9 cell glucocorticoid receptor was investigated by using one- and two-dimensional gel electrophoresis of proteolytic receptor fragments. One-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of receptor fragments isolated after trypsin digestion of immunopurified [ 3 H]dexamethasone 21-mesylate ([ 3 H]DM-) labeled receptor revealed the presence of a stable 26.5-kilodalton (kDa) steroid-containing non-DNA-binding fragment, derived from a larger, less stable, 29-kDa fragment. The 26.5-kDa tryptic fragment appeared to be completely contained within a 41-kDa, steroid-containing, DNA-binding species isolated after chymotrypsin digestion of the intact protein. Two-dimensional electrophoretic analysis of the [ 3 H]DM-labeled tryptic fragments resolved two 26.5-kDa and two 29-kDa components. This was the same number of isoforms seen in the intact protein, indicating that the charge heterogeneity of the steroid-binding protein is the result of modification within the steroid-containing, non-DNA-binding, 26.5-kDa tryptic fragment. Two-dimensional analysis of the 41-kDa [ 3 H]DM-labeled chymotryptic species revealed a pattern of isoforms more complex than that seen either in the intact protein or in the steroid-containing tryptic fragments. These results suggest that the 41-kDa [ 3 H]DM-labeled species resolved by one-dimensional SDS-PAGE after chymotrypsin digestion may be composed of several distinct proteolytic fragments

  15. 42 CFR 422.566 - Organization determinations.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Organization determinations. 422.566 Section 422... (CONTINUED) MEDICARE PROGRAM MEDICARE ADVANTAGE PROGRAM Grievances, Organization Determinations and Appeals § 422.566 Organization determinations. (a) Responsibilities of the MA organization. Each MA organization...

  16. Structure determination of a novel metal-organic compound synthesized from aluminum and 2,5-pyridinedicarboxylic acid

    DEFF Research Database (Denmark)

    Ståhl, Kenny; Brink, Bastian; Andersen, Jonas

    2011-01-01

    .979(1)°. The structure consists of aluminum ions coordinating N and O in distorted octahedra, sharing an edge through two hydroxide ions. These dinuclear complexes are connected by pydc ions, which at one end coordinate by nitrogen and oxygen and only by oxygen at the other end. The pydc orientation is reversed...... in the neighboring pydc, forming double stranded chains interconnected by the aluminum dinuclear complexes in a ladder-like arrangement along [001]....

  17. Ab initio structure determination of nanocrystals of organic pharmaceutical compounds by electron diffraction at room temperature using a Timepix quantum area direct electron detector

    Energy Technology Data Exchange (ETDEWEB)

    Genderen, E. van; Clabbers, M. T. B. [Biophysical Structural Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden (Netherlands); Center for Cellular Imaging and NanoAnalytics (C-CINA), Biozentrum, University of Basel, CH-4058 Basel (Switzerland); Das, P. P. [Nanomegas SPRL, Boulevard Edmond Machtens 79, B 1080, Brussels (Belgium); Stewart, A. [Department of Physics and Energy, Materials and Surface Science Institute (MSSI), University of Limerick, Limerick (Ireland); Nederlof, I. [Biophysical Structural Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden (Netherlands); Amsterdam Scientific Instruments, Postbus 41882, 1009 DB Amsterdam (Netherlands); Barentsen, K. C. [Biophysical Structural Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden (Netherlands); Portillo, Q. [Nanomegas SPRL, Boulevard Edmond Machtens 79, B 1080, Brussels (Belgium); Centres Científics i Tecnològics de la Universitat de Barcelona, University of Barcelona, Carrer de Lluís Solé i Sabaris, 1-3, Barcelona (Spain); Pannu, N. S. [Biophysical Structural Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden (Netherlands); Nicolopoulos, S. [Nanomegas SPRL, Boulevard Edmond Machtens 79, B 1080, Brussels (Belgium); Gruene, T., E-mail: tim.gruene@psi.ch [Biology and Chemistry, Laboratory of Biomolecular Research, Paul Scherrer Institute (PSI), 5232 Villigen (Switzerland); Abrahams, J. P., E-mail: tim.gruene@psi.ch [Biophysical Structural Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden (Netherlands); Center for Cellular Imaging and NanoAnalytics (C-CINA), Biozentrum, University of Basel, CH-4058 Basel (Switzerland); Biology and Chemistry, Laboratory of Biomolecular Research, Paul Scherrer Institute (PSI), 5232 Villigen (Switzerland)

    2016-02-05

    A specialized quantum area detector for electron diffraction studies makes it possible to solve the structure of small organic compound nanocrystals in non-cryo conditions by direct methods. Until recently, structure determination by transmission electron microscopy of beam-sensitive three-dimensional nanocrystals required electron diffraction tomography data collection at liquid-nitrogen temperature, in order to reduce radiation damage. Here it is shown that the novel Timepix detector combines a high dynamic range with a very high signal-to-noise ratio and single-electron sensitivity, enabling ab initio phasing of beam-sensitive organic compounds. Low-dose electron diffraction data (∼0.013 e{sup −} Å{sup −2} s{sup −1}) were collected at room temperature with the rotation method. It was ascertained that the data were of sufficient quality for structure solution using direct methods using software developed for X-ray crystallography (XDS, SHELX) and for electron crystallography (ADT3D/PETS, SIR2014)

  18. STRUCTURAL ORGANIZATION OF BACTERIAL UREASES

    Directory of Open Access Journals (Sweden)

    Lisnyak YuV

    2016-09-01

    Full Text Available This brief review concerns the basic principles of structural organization of multi-subunit bacterial ureases and formation of their quaternary structure. Urease is a nickel-containing enzyme (urea amidohydrolase, ЕС 3.5.1.5 that catalyses the hydrolysis of urea to get ammonia and carbamate which then decomposes with water to get ammonia and carbon dioxide. Urease is produced by bacteria, fungi, yeast and plants. On the basis of similarities in amino acid sequences, ureases assumed to have a similar structure and conservative catalytic mechanism. Within past two decades bacterial ureases have gained much attention in research field as a virulence factor in human and animal infections. The first crystal structure of urease has been determined for that from Klebsiella aerogenes. The native enzyme consists of three subunits, UreA (α-chain, UreB (β-chain and UreC (γ-chain, and contains four structural domains: two in α-chain (α-domain 1 and α-domain-2, one in β- and one in γ-chain. These three chains form a T-shaped heterotrimer αβγ. Three αβγ heterotrimers form quaternary complex (αβγ3. In case of Helicobacter pilori, the analogous trimers of corresponding dimeric subunits (αβ3 form tetrameric structure ((αβ34 in which four trimers are situated at the vertexes of the regular triangle pyramid. Active center is located in α-domain 1 and contains two atoms of nickel coordinated by residues His134, His136, carboxylated Lys217, His 246, His272 and Asp360, as well as residues involved in binding (His219 and catalysis (His320. Active site is capped by a flap that controls substrate ingress to and product egress from the dinickel center. Urease requires accessory proteins (UreD, UreF, UreG and UreE for the correct assembly of their Ni-containing metallocenters. The accessory proteins UreD, UreF, and UreG sequentially bind to the apoprotein (UreABC3 to finally form (UreABC-UreDFG3 activation complex. UreE metallochaperone delivers

  19. Determination of Three-Dimensional Morphology and Inner Structure of Second-Phase Inclusions in Metals by Non-Aqueous Solution Electrolytic and Room Temperature Organic Methods

    Directory of Open Access Journals (Sweden)

    Jing Guo

    2018-01-01

    Full Text Available The secondary-phase particles in metals, particularly those composed of non-metallic materials, are often detrimental to the mechanical properties of metals; thus, it is crucial to control inclusion formation and growth. One of the challenges is determining the three-dimensional morphology and inner structures of such inclusions. In this study, a non-aqueous solution electrolytic method and a room-temperature organic technique were developed based on the principle of electrochemistry to determine the three-dimensional morphologies and inner structures of non-metallic inclusions in Al-killed steel, Si-killed steel, and ductile cast iron. The inclusions were first extracted without any damage to the inclusions, and then the collected inclusions were wrapped and cut through Cu ion deposition. The results revealed that the inclusions in Al-killed steel had an irregular morphology, that those in the Si-killed steel were mainly spherical, and that almost all the spheroidal graphite in the ductile cast iron featured a uniform globular morphology. In addition, nucleation was not observed in the inner structures of the inclusions in the Al-killed steel, while some dendritic or rod-like MnS phase precipitates appeared on the silicate inclusion surfaces, and some silicate-rich phases were detected in their inner matrix. For spheroidal graphite, rare-earth oxides (one particle or more were observed as nuclei in the center of almost every graphite particle. The formation and evolution of inclusions in these types of metals can be better understood by means of the two developed methods.

  20. Development of methods for determining organic free radical structures by electron spin resonance and application to the radiation chemistry of nucleic acid model compounds

    International Nuclear Information System (INIS)

    Fouse, G.W. Jr.

    1977-01-01

    This project was undertaken with the objective of developing more efficient and reliable methods for the analysis of free radicals in organic single crystals. A technique was developed for the rapid calculation of single crystal ESR line positions and intensities. This method, which avoids the time-consuming matrix operations required by conventional methods, has been incorporated into a computer program for determining ESR parameters by the least-squares fitting of digitized ESR spectra. This program has been used to analyze complex spectra arising from a . CH 2 -CH 2 -O-PO 3 H - radical trapped in O-phosphorylethanolamine. A method was developed for the estimation of variance and covariance of eigenvectors and eigenvalues of experimentally-determined tensors. This error analysis is quite general, and may be applied to any tensors which can be determined by the non-linear least-squares fitting of ESR data. Monte-Carlo simulations have been employed to estimate the limitations of the approximation method. This error analysis has been included in the analysis of two phosphite radicals, - O 2 -P-OX, found in single crystals of O-phosphorylethanolamine. To aid in the formulation and evaluation of free radical models, a generalized method for the calculation of theoretically-expected hyperfine coupling tensors for arbitrary radical models was developed. Tensors are calculated for a furan-type radical which may be found in 5' dCMP. These calculated tensors are compared with tensors determined by an ENDOR experiment. Two ENDOR studies were done, one in 5' dCMP, the other in L-asparagine. The observed radical in 5' dCMP is allylic, characterized by coupling to three α-hydrogens. In L-asparagine, the dominant room-temperature radical has the form CO(NH 2 )CHCH(N + H 3 )CO 2 - . In both these studies, a series of molecular orbital calculations were performed as a means of substantiating the postulated radical structures

  1. 42 CFR 417.838 - Organization determinations.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Organization determinations. 417.838 Section 417... (CONTINUED) MEDICARE PROGRAM HEALTH MAINTENANCE ORGANIZATIONS, COMPETITIVE MEDICAL PLANS, AND HEALTH CARE PREPAYMENT PLANS Health Care Prepayment Plans § 417.838 Organization determinations. (a) Actions that are...

  2. Determination of the structure of the organized phase of the block copolymer PEO-PPO-PEO in aqueous solutions under flow by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Perreur, Christelle; Habas, Jean-Pierre; Francois, Jeanne; Peyrelasse, Jean; Lapp, Alain

    2002-01-01

    The organization of Tetronic 908 registered (T908), a star copolymer of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) blocks, has been examined. Above critical conditions of temperature and concentration, the micelles formed by the aggregation of PPO units self-organize into particular structures. While small-angle neutron scattering (SANS) characterizations performed with static conditions demonstrate the organization of the medium, the experimental results do not allow us to make a distinction between simple cubic and body-centered-cubic structures. However, SANS measurements realized under shear produce characteristic diffraction diagrams. In this paper, an accurate methodology is proposed to identify, without ambiguity, the exact nature of the organized phase. Applied to our system, indexing of the diffraction pattern spots reveals that the organization of T908 is of bcc type oriented with the [111] direction parallel to the direction of flow, but the crystals can present any orientation about this direction. The lattice size has been estimated and compared to previous published results

  3. Managing mechanistic and organic structure in health care organizations.

    Science.gov (United States)

    Olden, Peter C

    2012-01-01

    Managers at all levels in a health care organization must organize work to achieve the organization's mission and goals. This requires managers to decide the organization structure, which involves dividing the work among jobs and departments and then coordinating them all toward the common purpose. Organization structure, which is reflected in an organization chart, may range on a continuum from very mechanistic to very organic. Managers must decide how mechanistic versus how organic to make the entire organization and each of its departments. To do this, managers should carefully consider 5 factors for the organization and for each individual department: external environment, goals, work production, size, and culture. Some factors may push toward more mechanistic structure, whereas others may push in the opposite direction toward more organic structure. Practical advice can help managers at all levels design appropriate structure for their departments and organization.

  4. Crystal structure determination of Efavirenz

    International Nuclear Information System (INIS)

    Popeneciu, Horea; Dumitru, Ristoiu; Tripon, Carmen; Borodi, Gheorghe; Pop, Mihaela Maria

    2015-01-01

    Needle-shaped single crystals of the title compound, C 14 H 9 ClF 3 NO 2 , were obtained from a co-crystallization experiment of Efavirenz with maleic acid in a (1:1) ratio, using methanol as solvent. Crystal structure determination at room temperature revealed a significant anisotropy of the lattice expansion compared to the previously reported low-temperature structure. In both low- and room temperature structures the cyclopropylethynyl fragment in one of the asymmetric unit molecules is disordered. While at low-temperature only one C atom exhibits positional disorder, at room temperature the disorder is present for two C atoms of the cyclopropane ring

  5. Gender Structure and Spatial Organization

    Directory of Open Access Journals (Sweden)

    Minoosh Sadoughianzadeh

    2013-11-01

    Full Text Available As a contribution to the widespread debate on the “gender reading” of the “built environment,” this article aims to situate the subject in a new context, the Iranian society. To depict the subject, two distinct traditional architectures of the region, associated with their respective socio-spatial organizations, have been comparatively explored: the “Introvert” and “Extrovert.” These two almost ageless “Introvert” and “Extrovert” architectures, evolved through centuries in different geographical parts of the country, are spatial patterns aptly illustrating how the “gender structure” of each social organization has contributed to the formation of the relevant “physical space” and, further, how the specific “gender relationships” are pertinently structured within each one of the two types of the spaces. Based on a systematic approach and through concentration on the macro-socio-spatial organization, this article is to explore the gender/space associated variations within either of the social systems they belong to. This perspective is particularly instrumental in pinpointing the Introvert and Extrovert architectures in the context of their social organizations and carefully scrutinizing “gender” and “space” categories as systematically integrated variables.

  6. Domination, self-determination and circular organizing

    NARCIS (Netherlands)

    Romme, A.G.L.

    2002-01-01

    The emergence of self-organizing forms of control, based on the idea of self-determination, have challenged traditional forms of control based on the concept of domination. As such, self-determination has been put forward as an alternative rather than as a complement to domination. This paper

  7. Re-Ordering Structural Dimensions for Nigerian Organizations ...

    African Journals Online (AJOL)

    The organization structure (OS) reflects the interface of the dimensions of the OS, the model in place and the mix of determinants of OS. This paper focuses on the organization structure (OS) to find out, not just the consistency of the structural properties with the OS but also the potentials of OS oriented towards the realization ...

  8. METHODS FOR THE DETERMINATION OF TOTAL ORGANIC ...

    Science.gov (United States)

    Organic matter in soils and sediments is widely distributed over the earth's surface occurring in almost all terrestrial and aquatic environments (Schnitzer, 1978). Soils and sediments contain a large variety of organic materials ranging from simple sugars and carbohydrates to the more complex proteins, fats, waxes, and organic acids. Important characteristics of the organic matter include their ability to: form water-soluble and water- insoluble complexes with metal ions and hydrous oxides; interact with clay minerals and bind particles together; sorb and desorb both naturally-occurring and anthropogenically-introduced organic compounds; absorb and release plant nutrients; and hold water in the soil environment. As a result of these characteristics, the determination of total organic carbon (a measure of one of the chemical components of organic matter that is often used as an indicator of its presence in a soil or sediment) is an essential part of any site characterization since its presence or absence can markedly influence how chemicals will react in the soil or sediment. Soil and sediment total organic carbon (TOC) determinations are typically requested with contaminant analyses as part of an ecological risk assessment data package. TOC contents may be used qualitatively to assess the nature of the sampling location (e.g., was it a depositional area) or may be used to normalize portions of the analytical chemistry data set (e.g., equilibrium partitioning).

  9. 16 CFR 0.9 - Organization structure.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Organization structure. 0.9 Section 0.9 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE ORGANIZATION § 0.9 Organization structure. The Federal Trade Commission comprises the following principal units...

  10. Structure determination of enterovirus 71

    Energy Technology Data Exchange (ETDEWEB)

    Plevka, Pavel; Perera, Rushika; Cardosa, Jane; Kuhn, Richard J.; Rossmann, Michael G. (Purdue); (Sentinext)

    2013-02-20

    Enterovirus 71 is a picornavirus that causes hand, foot and mouth disease but may induce fatal neurological illness in infants and young children. Enterovirus 71 crystallized in a body-centered orthorhombic space group with two particles in general orientations in the crystallographic asymmetric unit. Determination of the particle orientations required that the locked rotation function excluded the twofold symmetry axes from the set of icosahedral symmetry operators. This avoided the occurrence of misleading high rotation-function values produced by the alignment of icosahedral and crystallographic twofold axes. Once the orientations and positions of the particles had been established, the structure was solved by molecular replacement and phase extension.

  11. The Roles of Structural Order and Intermolecular Interactions in Determining Ionization Energies and Charge-Transfer State Energies in Organic Semiconductors

    KAUST Repository

    Graham, Kenneth

    2016-08-17

    The energy landscape in organic semiconducting materials greatly influences charge and exciton behavior, which are both critical to the operation of organic electronic devices. These energy landscapes can change dramatically depending on the phases of material present, including pure phases of one molecule or polymer and mixed phases exhibiting different degrees of order and composition. In this work, ultraviolet photoelectron spectroscopy measurements of ionization energies (IEs) and external quantum efficiency measurements of charge-transfer (CT) state energies (ECT) are applied to molecular photovoltaic material systems to characterize energy landscapes. The results show that IEs and ECT values are highly dependent on structural order and phase composition. In the sexithiophene:C60 system both the IEs of sexithiophene and C60 shift by over 0.4 eV while ECT shifts by 0.5 eV depending on molecular composition. By contrast, in the rubrene:C60 system the IE of rubrene and C60 vary by ≤0.11 eV and ECT varies by ≤0.04 eV as the material composition varies. These results suggest that energy landscapes can exist whereby the binding energies of the CT states are overcome by energy offsets between charges in CT states in mixed regions and free charges in pure phases. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. [Structure-functional organization of eukaryotic high-affinity copper importer CTR1 determines its ability to transport copper, silver and cisplatin].

    Science.gov (United States)

    Skvortsov, A N; Zatulovskiĭ, E A; Puchkova, L V

    2012-01-01

    It was shown recently, that high affinity Cu(I) importer eukaryotic protein CTR1 can also transport in vitro abiogenic Ag(I) ions and anticancer drug cisplatin. At present there is no rational explanation how CTR1 can transfer platinum group, which is different by coordination properties from highly similar Cu(I) and Ag(I). To understand this phenomenon we analyzed 25 sequences of chordate CTR1 proteins, and found out conserved patterns of organization of N-terminal extracellular part of CTR1 which correspond to initial metal binding. Extracellular copper-binding motifs were qualified by their coordination properties. It was shown that relative position of Met- and His-rich copper-binding motifs in CTR1 predisposes the extracellular CTR1 part to binding of copper, silver and cisplatin. Relation between tissue-specific expression of CTR1 gene, steady-state copper concentration, and silver and platinum accumulation in organs of mice in vivo was analyzed. Significant positive but incomplete correlation exists between these variables. Basing on structural and functional peculiarities of N-terminal part of CTR1 a hypothesis of coupled transport of copper and cisplatin has been suggested, which avoids the disagreement between CTR1-mediated cisplatin transport in vitro, and irreversible binding of platinum to Met-rich peptides.

  13. The Design of Project Management Structural Organization

    OpenAIRE

    Dumitru Constantinescu; Cristian Etegan

    2007-01-01

    The relationships organization-suppliers-customers have recently known major changes in the structure of services and have made the organization develop its managerial and professional competencies in order to do projects. The qualified organization is the most trust-worthy in the process of doing a project. The participation of an organization in doing projects depends on a multitude of factors. Out of these factors, the structural organization comes forth, as it represents the variable with...

  14. Organic Determinants of Learning and Behavioral Disorders.

    Science.gov (United States)

    Philpott, William H.; And Others

    Theories regarding organic determinants of learning and behavior disorders are reviewed historically. Cases illustrating how a bio-ecologic examination can isolate the substances to which a person reacts and some of the reasons for those reactions are presented; and the role of various disorders in relation to the central nervous system is…

  15. The Roles of Structural Order and Intermolecular Interactions in Determining Ionization Energies and Charge-Transfer State Energies in Organic Semiconductors

    KAUST Repository

    Graham, Kenneth; Ngongang Ndjawa, Guy Olivier; Conron, Sarah M.; Munir, Rahim; Vandewal, Koen; Chen, John J.; Sweetnam, Sean; Thompson, Mark E.; Salleo, Alberto; Mcgehee, Michael D.; Amassian, Aram

    2016-01-01

    The energy landscape in organic semiconducting materials greatly influences charge and exciton behavior, which are both critical to the operation of organic electronic devices. These energy landscapes can change dramatically depending on the phases

  16. Introduction to the structures determination methods using X-ray diffraction in monocrystals: application to some lanthanides and transition metals complexes with organic ligands

    International Nuclear Information System (INIS)

    Oliva, G.

    1983-01-01

    The crystal structure of the complexes Ln (Cl O 4 ) 3 .6[P O N H 2 (C 6 H 5 ) 2 ] where Ln = Eu, La, Cu[N H 2 (C H 3 ) 2 C C O 2 ] 2 , Ni Br 2 .4[As O(C 6 H 5 ) 3 ]. 8 H 2 O (green), Ni Br 2 .4[As O (C 6 H 5 ) 3 ]. 1,5 (C H 3 C 6 H 5 ).H 2 O (orange) and of the ligand P O N H 2 (C 6 H 5 ) 2 have been determined by X-ray diffraction. The complexes involving lanthanide ions refined to final R factors of R(Eu) = 0.125 and R(La) = 0.133 and the following main features were found: the crystal system is cubic; the cation is coordinated to six ligand oxygens in octahedral (Eu) and trigonal anti prismatic (La) configurations with the rate earths on positions of high symmetry (23 for Eu and 3-bar for La); the rest of the structures shows different degrees of disorder. In the light of the geometrical configuration, the occurrence of a strong band 5 D O - 7 F 2 in the fluorescence spectrum of the Eu complex, forbidden on symmetry grounds, is interpreted as a consequence of vibronic coupling. A splitting of the infrared ν P=0 band in the La complex is attributed to the presence of P = 0 groups non-equivalently bonded to the rare earth due to the disorder of this atom. (author)

  17. Structure and Structure-activity Relationship of Functional Organic Molecules

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    @@ Research theme The group is made up of junior scientists from the State Key Laboratory of Elemento-organic Chemistry, Nankai University.The scientists focus their studis on the structure and structure-activity relationship of functional organic molecules not only because it has been the basis of their research, but also because the functional study of organic compounds is now a major scientific issue for organic chemists around the world.

  18. Organizational structure in process-based organizations

    NARCIS (Netherlands)

    Vanhaverbeke, W.P.M.; Torremans, H.P.M.

    1999-01-01

    This paper investigates the role of the organization structure in process-based organizations. We argue that companies cannot be designed upon organizational processes only or that process management can be simply imposed as an additional structural dimension on top of the existing functional or

  19. Solution NMR structure determination of proteins revisited

    International Nuclear Information System (INIS)

    Billeter, Martin; Wagner, Gerhard; Wuethrich, Kurt

    2008-01-01

    This 'Perspective' bears on the present state of protein structure determination by NMR in solution. The focus is on a comparison of the infrastructure available for NMR structure determination when compared to protein crystal structure determination by X-ray diffraction. The main conclusion emerges that the unique potential of NMR to generate high resolution data also on dynamics, interactions and conformational equilibria has contributed to a lack of standard procedures for structure determination which would be readily amenable to improved efficiency by automation. To spark renewed discussion on the topic of NMR structure determination of proteins, procedural steps with high potential for improvement are identified

  20. [Qualitative Determination of Organic Vapour Using Violet and Visible Spectrum].

    Science.gov (United States)

    Jiang, Bo; Hu, Wen-zhong; Liu, Chang-jian; Zheng, Wei; Qi, Xiao-hui; Jiang, Ai-li; Wang, Yan-ying

    2015-12-01

    Vapours of organic matters were determined qualitatively employed with ultraviolet-visible absorption spectroscopy. Vapours of organic matters were detected using ultraviolet-visible spectrophotometer employing polyethylene film as medium, the ultraviolet and visible absorption spectra of vegetable oil vapours of soybean oil, sunflower seed oil, peanut oil, rapeseed oil, sesame oil, cotton seed oil, tung tree seed oil, and organic compound vapours of acetone, ethyl acetate, 95% ethanol, glacial acetic acid were obtained. Experimental results showed that spectra of the vegetable oil vapour and the organic compound vapour could be obtained commendably, since ultra violet and visible spectrum of polyethylene film could be deducted by spectrograph zero setting. Different kinds of vegetable oils could been distinguished commendably in the spectra since the λ(max), λ(min), number of absorption peak, position, inflection point in the ultra violet and visible spectra obtained from the vapours of the vegetable oils were all inconsistent, and the vapours of organic compounds were also determined perfectly. The method had a good reproducibility, the ultraviolet and visible absorption spectra of the vapours of sunflower seed oil in 10 times determination were absolutely the same. The experimental result indicated that polyethylene film as a kind of medium could be used for qualitative analysis of ultraviolet and visible absorption spectroscopy. The method for determination of the vapours of the vegetable oils and organic compounds had the peculiarities of fast speed analysis, well reproducibility, accuracy and reliability and low cost, and so on. Ultraviolet and visible absorption spectrum of organic vapour could provide feature information of material vapour and structural information of organic compound, and provide a novel test method for identifying vapour of compound and organic matter.

  1. Minerals with metal-organic framework structures.

    Science.gov (United States)

    Huskić, Igor; Pekov, Igor V; Krivovichev, Sergey V; Friščić, Tomislav

    2016-08-01

    Metal-organic frameworks (MOFs) are an increasingly important family of advanced materials based on open, nanometer-scale metal-organic architectures, whose design and synthesis are based on the directed assembly of carefully designed subunits. We now demonstrate an unexpected link between mineralogy and MOF chemistry by discovering that the rare organic minerals stepanovite and zhemchuzhnikovite exhibit structures found in well-established magnetic and proton-conducting metal oxalate MOFs. Structures of stepanovite and zhemchuzhnikovite, exhibiting almost nanometer-wide and guest-filled apertures and channels, respectively, change the perspective of MOFs as exclusively artificial materials and represent, so far, unique examples of open framework architectures in organic minerals.

  2. Structure determination of disordered organic molecules on surfaces from the Bragg spots of low-energy electron diffraction and total energy calculations

    International Nuclear Information System (INIS)

    Poon, H.C.; Weinert, M.; Saldin, D.K.; Stacchiola, D.; Zheng, T.; Tysoe, W.T.

    2004-01-01

    We show that an analysis of the intensity versus energy variation of Bragg spots due to low-energy electron diffraction from a disordered overlayer of molecules on a crystal surface allows a much more convenient method of determining the local adsorption geometries of such molecules than previously analyzed weak diffuse diffraction patterns. For the case of methanol on Pd(111), we show that the geometry determined by this means from experimental diffraction data is in excellent agreement with the predictions of density functional total energy calculations

  3. Determinants of Glycosaminoglycan (GAG Structure

    Directory of Open Access Journals (Sweden)

    Kristian Prydz

    2015-08-01

    Full Text Available Proteoglycans (PGs are glycosylated proteins of biological importance at cell surfaces, in the extracellular matrix, and in the circulation. PGs are produced and modified by glycosaminoglycan (GAG chains in the secretory pathway of animal cells. The most common GAG attachment site is a serine residue followed by a glycine (-ser-gly-, from which a linker tetrasaccharide extends and may continue as a heparan sulfate, a heparin, a chondroitin sulfate, or a dermatan sulfate GAG chain. Which type of GAG chain becomes attached to the linker tetrasaccharide is influenced by the structure of the protein core, modifications occurring to the linker tetrasaccharide itself, and the biochemical environment of the Golgi apparatus, where GAG polymerization and modification by sulfation and epimerization take place. The same cell type may produce different GAG chains that vary, depending on the extent of epimerization and sulfation. However, it is not known to what extent these differences are caused by compartmental segregation of protein cores en route through the secretory pathway or by differential recruitment of modifying enzymes during synthesis of different PGs. The topic of this review is how different aspects of protein structure, cellular biochemistry, and compartmentalization may influence GAG synthesis.

  4. STRUCTURE AND COOPTATION IN ORGANIZATION NETWORK

    Directory of Open Access Journals (Sweden)

    Valéria Riscarolli

    2007-10-01

    Full Text Available Business executive are rethinking business concept, based on horizontalization principles. As so, most organizational functions are outsourced, leading the enterprise to build business through a network of organizations. Here we study the case of Cia Hering’s network of organizations, a leader in knit apparel segment in Latin America (IEMI, 2004, looking at the network’s structure and levels of cooptation. A theoretical model was used using Quinn et al. (2001 “sun ray” network structure as basis to analyze the case study. Main results indicate higher degree of structural conformity, but incipient degree of coopetation in the network.

  5. Monte Carlo determination of heteroepitaxial misfit structures

    DEFF Research Database (Denmark)

    Baker, J.; Lindgård, Per-Anker

    1996-01-01

    We use Monte Carlo simulations to determine the structure of KBr overlayers on a NaCl(001) substrate, a system with large (17%) heteroepitaxial misfit. The equilibrium relaxation structure is determined for films of 2-6 ML, for which extensive helium-atom scattering data exist for comparison...

  6. Determinism, chaos, self-organization and entropy

    Directory of Open Access Journals (Sweden)

    JOSÉ PONTES

    2016-06-01

    Full Text Available ABSTRACT We discuss two changes of paradigms that occurred in science along the XXth century: the end of the mechanist determinism, and the end of the apparent incompatibility between biology, where emergence of order is law, and physics, postulating a progressive loss of order in natural systems. We recognize today that three mechanisms play a major role in the building of order: the nonlinear nature of most evolution laws, along with distance to equilibrium, and with the new paradigm, that emerged in the last forty years, as we recognize that networks present collective order properties not found in the individual nodes. We also address the result presented by Blumenfeld (L.A. Blumenfeld, Problems of Biological Physics, Springer, Berlin, 1981 showing that entropy decreases resulting from building one of the most complex biological structures, the human being, are small and may be trivially compensated for compliance with thermodynamics. Life is made at the expense of very low thermodynamic cost, so thermodynamics does not pose major restrictions to the emergence of life. Besides, entropy does not capture our idea of order in biological systems. The above questions show that science is not free of confl icts and backlashes, often resulting from excessive extrapolations.

  7. Determinism, chaos, self-organization and entropy.

    Science.gov (United States)

    Pontes, José

    2016-01-01

    We discuss two changes of paradigms that occurred in science along the XXth century: the end of the mechanist determinism, and the end of the apparent incompatibility between biology, where emergence of order is law, and physics, postulating a progressive loss of order in natural systems. We recognize today that three mechanisms play a major role in the building of order: the nonlinear nature of most evolution laws, along with distance to equilibrium, and with the new paradigm, that emerged in the last forty years, as we recognize that networks present collective order properties not found in the individual nodes. We also address the result presented by Blumenfeld (L.A. Blumenfeld, Problems of Biological Physics, Springer, Berlin, 1981) showing that entropy decreases resulting from building one of the most complex biological structures, the human being, are small and may be trivially compensated for compliance with thermodynamics. Life is made at the expense of very low thermodynamic cost, so thermodynamics does not pose major restrictions to the emergence of life. Besides, entropy does not capture our idea of order in biological systems. The above questions show that science is not free of confl icts and backlashes, often resulting from excessive extrapolations.

  8. Tree-Structured Digital Organisms Model

    Science.gov (United States)

    Suzuki, Teruhiko; Nobesawa, Shiho; Tahara, Ikuo

    Tierra and Avida are well-known models of digital organisms. They describe a life process as a sequence of computation codes. A linear sequence model may not be the only way to describe a digital organism, though it is very simple for a computer-based model. Thus we propose a new digital organism model based on a tree structure, which is rather similar to the generic programming. With our model, a life process is a combination of various functions, as if life in the real world is. This implies that our model can easily describe the hierarchical structure of life, and it can simulate evolutionary computation through mutual interaction of functions. We verified our model by simulations that our model can be regarded as a digital organism model according to its definitions. Our model even succeeded in creating species such as viruses and parasites.

  9. Determining organ dose: the holy grail

    International Nuclear Information System (INIS)

    Samei, Ehsan; Tian, Xiaoyu; Segars, W.P.

    2014-01-01

    Among the various metrics to quantify CT radiation dose, organ dose is generally regarded as one of the best to reflect patient radiation burden. Organ dose is dependent on two main factors, namely patient anatomy and irradiation field. An accurate estimation of organ dose requires detailed modeling of both factors. The modeling of patient anatomy needs to reflect the anatomical diversity and complexity across the population so that the attributes of a given clinical patient can be properly accounted for. The modeling of the irradiation field needs to accurately reflect the CT system condition, especially the tube current modulation (TCM) technique. We present an atlas-based method to model patient anatomy via a library of computational phantoms with representative ages, sizes and genders. A clinical patient is matched with a corresponding computational phantom to obtain a representation of patient anatomy. The irradiation field of the CT system is modeled using a validated Monte Carlo simulation program. The tube current modulation profiles are simulated using a manufacturer-generalizable ray-tracing algorithm. Combining the patient model, Monte Carlo results, and TCM profile, organ doses are obtained by multiplying organ dose values from a fixed mA scan (normalized to CTDI vol -normalized, denoted as h organ ) and an adjustment factor that reflects the specific irradiation of each organ. The accuracy of the proposed method was quantified by simulating clinical abdominopelvic examinations of 58 patients. The predicted organ doses showed good agreement with simulated organ dose across all organs and modulation schemes. For an average CTDI vol of a CT exam of 10 mGy, the absolute median error across all organs was 0.64 mGy (-0.21 and 0.97 for 25th and 75th percentiles, respectively). The percentage differences were within 15%. The study demonstrates that it is feasible to estimate organ doses in clinical CT examinations for protocols without and with tube current

  10. Structural Genomics of Minimal Organisms: Pipeline and Results

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung-Hou; Shin, Dong-Hae; Kim, Rosalind; Adams, Paul; Chandonia, John-Marc

    2007-09-14

    The initial objective of the Berkeley Structural Genomics Center was to obtain a near complete three-dimensional (3D) structural information of all soluble proteins of two minimal organisms, closely related pathogens Mycoplasma genitalium and M. pneumoniae. The former has fewer than 500 genes and the latter has fewer than 700 genes. A semiautomated structural genomics pipeline was set up from target selection, cloning, expression, purification, and ultimately structural determination. At the time of this writing, structural information of more than 93percent of all soluble proteins of M. genitalium is avail able. This chapter summarizes the approaches taken by the authors' center.

  11. Determinants and antecedents of sales organization effectiveness

    Directory of Open Access Journals (Sweden)

    Andrea Razum

    2011-12-01

    Full Text Available The fundamental objective of this paper was to identify and analyze the main antecedents of sales organization effectiveness in order to offer the guidelines for improving the standard sales practice. In addition to the customary challenges of achieving anticipated sales results, rising pressures of the contemporary business environment underscore the importance of establishing a more effective sales organization. The aim of the empirical research was to identify the sources of effectiveness of sales organizations based on the comparison between two groups of organizations, namely, the relatively high and low performing ones. The concept of sales performance was observed through five distinct factors: sales management activities, sales force characteristics, sales organization design and sales force effectiveness with regard to the sales outcome of these organizations and their behavior. The analysis of the results led to the conclusion that the most important sources of sales effectiveness are the activities of sales managers targeted towards monitoring and rewarding. Moreover, sales managers in relatively more effective organizations reported much higher satisfaction with the design of sales territories. Sales people in effective companies are highly motivated and committed to the organization. In addition, they are also considerably better at achieving high levels of outcome performance. The research presents an addition to a number of similar studies conducted worldwide but, more importantly, it contributes to the exceptionally small number of sales management studies carried out in Croatia. For a more complete analysis it would be necessary to include the variables of the external environment and examine the potential moderating impact of product type and industry on the overall sales effectiveness.

  12. Perceptions of the organization's climate: influenced by the organization's structure?

    Science.gov (United States)

    Grigsby, K A

    1991-02-01

    Currently, little is known about organizational climates in schools of nursing, and what structural factors are associated with climate variations. The purpose of this study is to describe the organizational structure and climate, and the interrelationship between these factors, in two schools of nursing. Results indicated that the sample organizations exhibited characteristics of both the bureaucratic and professional models of organizational structure, although one school was more closely aligned to the professional model. Organizational climates differed in the two schools, and the school that structurally resembled the professional model had a more facilitative climate. Organizational structure was significantly (p less than .01) related to the climate dimensions of autonomy (r = -.35), work pressure (r = .49), and control (r = .59). The schools differed significantly (p less than .01) on the climate dimensions of administrative support (t = 3.31, df = 54), autonomy (t = 3.30, df = 56), work pressure (t = -4.36, df = 60), and control (t = -6.74, df = 55). Administrative support and autonomy were higher in the school structurally resembling the professional model, and work pressure and control were higher in the school structurally resembling the bureaucratic model.

  13. Growth of pseudomorphic structures through organic epitaxy

    International Nuclear Information System (INIS)

    Kaviyil, Sreejith Embekkat; Sassella, Adele; Borghesi, Alessandro; Campione, Marcello; Su Genbo; He Youping; Chen Chenjia

    2012-01-01

    The control of molecular orientation in thin solid film phases of organic semiconductors is a basic factor for the exploitation of their physical properties for optoelectronic devices. We compare structural and optical properties of thin films of the organic semiconductor α-quarterthiophene grown by molecular beam epitaxy on different organic substrates. We show how epitactic interactions, characteristic of the surface of organic crystals, can drive the orientation of the crystalline overlayer and the selection of specific polymorphs and new pseudomorphic phases. We identify a key role in this phenomenon played by the marked groove-like corrugations present in some organic crystal surfaces. Since different polymorphs possess rather different performance in terms of, e.g., charge carrier mobility, this strategy is demonstrated to allow for the growth of oriented phases with enhanced physical properties, while keeping the substrate at room temperature. These results provide useful guidelines for the design of technological substrates for organic epitaxy and they substantiate the adoption of an organic epitaxy approach for the fabrication of optoelectronic devices based on thin films of organic semiconductors.

  14. Structural determinants of students' employability: Influence of ...

    African Journals Online (AJOL)

    Structural determinants of students' employability: Influence of career ... greatest influence on students' employability, followed by decision-making skills, and ... efforts in developing app-ropriate strategies so as to engage undergraduates with ...

  15. Structural complexities in the active layers of organic electronics.

    Science.gov (United States)

    Lee, Stephanie S; Loo, Yueh-Lin

    2010-01-01

    The field of organic electronics has progressed rapidly in recent years. However, understanding the direct structure-function relationships between the morphology in electrically active layers and the performance of devices composed of these materials has proven difficult. The morphology of active layers in organic electronics is inherently complex, with heterogeneities existing across multiple length scales, from subnanometer to micron and millimeter range. A major challenge still facing the organic electronics community is understanding how the morphology across all of the length scales in active layers collectively determines the device performance of organic electronics. In this review we highlight experiments that have contributed to the elucidation of structure-function relationships in organic electronics and also point to areas in which knowledge of such relationships is still lacking. Such knowledge will lead to the ability to select active materials on the basis of their inherent properties for the fabrication of devices with prespecified characteristics.

  16. Resensi Buku: Organization Strategy, Structure, and Process

    Directory of Open Access Journals (Sweden)

    Ayi Ahadiyat

    2009-08-01

    Full Text Available Book ReviewJudul Buku    : Organization Strategy, Structure, and ProcessPenulis    : Raymond E. Miles and Charles C. SnowPenerbit     : McGraw-Hill Kogakusha, Ltd (International Student Edition, Tokyo,  274 hlm.Tahun    : 1978

  17. Protein Structure Determination Using Chemical Shifts

    DEFF Research Database (Denmark)

    Christensen, Anders Steen

    is determined using only chemical shifts recorded and assigned through automated processes. The CARMSD to the experimental X-ray for this structure is 1.1. Å. Additionally, the method is combined with very sparse NOE-restraints and evolutionary distance restraints and tested on several protein structures >100...

  18. STRUCTURIZATION OF COMPETITIVE CAPACITY OF TRADE ORGANIZATION

    Directory of Open Access Journals (Sweden)

    N. A. Sеrеbrуаkоvа

    2015-01-01

    Full Text Available The modern consumer market is characterized by a complex of immanent tendencies of development, the competitive relations reflecting specifics inherent in it. These tendencies of development of the competitive environment of the consumer market are in many respects caused by a state and extent of use of competitive capacity of the organizations functioning in this market. This obvious circumstance causes the necessity of complex scientific research of competitive capacity of trade organizations, including its structures, for definition of prospects of its sustainable strategic development. Immanent properties of competitive capacity of trade organization allowed to study in detail its structure, by means of the substantial review of the existing options of its representation and their systematization on specific, element and system signs. In development of specific structure of competitive potential its addition commercial, technological, communication, consumer and image the potentials reflecting functional and branch specifics of activity of trade organization is offered. The system of elements of competitive capacity of trade organization is given by its structure-forming types. It is proved that these elements aren't characterized by strict distribution by types of potentials, and separate from elements are universal, accepted for simultaneous use when forming all types of potential. Allocation of a system sign of structurization of competitive potential was based on situation that "systemacity" has to be provided not so much with hierarchy of hierarchy of types and elements of potential, their interrelations, how many possibility of the accounting of various classification signs allowing to typify competitive potential as system integrity, regardless of its separate types. Those signs were the stage of a demand and level of use in economic activity, economic feasibility of existence of unrealized potential, the origin nature.

  19. Overcoming barriers to membrane protein structure determination.

    Science.gov (United States)

    Bill, Roslyn M; Henderson, Peter J F; Iwata, So; Kunji, Edmund R S; Michel, Hartmut; Neutze, Richard; Newstead, Simon; Poolman, Bert; Tate, Christopher G; Vogel, Horst

    2011-04-01

    After decades of slow progress, the pace of research on membrane protein structures is beginning to quicken thanks to various improvements in technology, including protein engineering and microfocus X-ray diffraction. Here we review these developments and, where possible, highlight generic new approaches to solving membrane protein structures based on recent technological advances. Rational approaches to overcoming the bottlenecks in the field are urgently required as membrane proteins, which typically comprise ~30% of the proteomes of organisms, are dramatically under-represented in the structural database of the Protein Data Bank.

  20. Structural Capability of an Organization toward Innovation Capability

    DEFF Research Database (Denmark)

    Nielsen, Susanne Balslev; Momeni, Mostafa

    2016-01-01

    The scholars in the field of strategic management have developed two major approaches for attainment of competitive advantage: an approach based on environmental opportunities, and another one based on internal capabilities of an organization. Some investigations in the last two decades have...... indicated that the advantages relying on the internal capabilities of organizations may determine the competitive position of organizations better than environmental opportunities do. Characteristics of firms shows that one of the most internal capabilities that lead the organizations to the strongest...... competitive advantage in the organizations is the innovation capability. The innovation capability is associated with other organizational capabilities, and many organizations have focused on the need to identify innovation capabilities.This research focuses on recognition of the structural aspect...

  1. Determining organic pollutants in automotive industry sludge.

    Science.gov (United States)

    Munaretto, Juliana S; Wonghon, Audrey L; von Mühlen, Carin

    2012-12-01

    In Brazil, the policy for disposing industrial sludge is changing from an emphasis on using controlled landfills to other treatment or co-processing methods; however, the monitoring of organic pollutants is not mandatory. The present study evaluated two general screening methods for organic pollutants in sludge generated in an automotive industrial complex in southern Brazil. The screening was performed using Soxhlet and sonication extractions and Gas Chromatograph coupled with Quadrupole Mass Spectrometry (GC/qMS). It was concluded that both techniques were effective and that most of the compounds identified were alkanes, phenols and esters. Important pollutants were detected in the sludge, which confirms the necessity of monitoring this type of residue.

  2. Capital Structure Determinants and Governance Structure Variety in Franchising

    NARCIS (Netherlands)

    T. Jiang (Tao)

    2009-01-01

    textabstractThis thesis investigates two questions: the determinants of capital structure in franchising and its subsequent impact on the franchise financing decisions; and the efficient governance structure choice in franchising. We posit that firms franchise in order to benefit from the reduced

  3. Integral Design workshops: organization, structure and testing

    OpenAIRE

    Zeiler, W Wim; Savanovic, P Perica

    2010-01-01

    The purpose of this paper is to achieve an understanding of design activities in the context of building design. The starting point is an overview of design research and design methodology. From the insights gained by this analysis of design in this specific context, we present an 'organization structure and design' workshop approach for collaborative multi-discipline design management. The workshops set-up, used to implement and to test the approach, are presented as well as the experiences ...

  4. Advances on surface structural determination by LEED

    International Nuclear Information System (INIS)

    Soares, Edmar A; De Carvalho, Vagner E; De Castilho, Caio M C

    2011-01-01

    In the last 40 years, low energy electron diffraction (LEED) has proved to be the most reliable quantitative technique for surface structural determination. In this review, recent developments related to the theory that gives support to LEED structural determination are discussed under a critical analysis of the main theoretical approximation-the muffin-tin calculation. The search methodologies aimed at identifying the best matches between theoretical and experimental intensity versus voltage curves are also considered, with the most recent procedures being reviewed in detail. (topical review)

  5. Structures of SAS-6 suggest its organization in centrioles.

    Science.gov (United States)

    van Breugel, Mark; Hirono, Masafumi; Andreeva, Antonina; Yanagisawa, Haru-aki; Yamaguchi, Shoko; Nakazawa, Yuki; Morgner, Nina; Petrovich, Miriana; Ebong, Ima-Obong; Robinson, Carol V; Johnson, Christopher M; Veprintsev, Dmitry; Zuber, Benoît

    2011-03-04

    Centrioles are cylindrical, ninefold symmetrical structures with peripheral triplet microtubules strictly required to template cilia and flagella. The highly conserved protein SAS-6 constitutes the center of the cartwheel assembly that scaffolds centrioles early in their biogenesis. We determined the x-ray structure of the amino-terminal domain of SAS-6 from zebrafish, and we show that recombinant SAS-6 self-associates in vitro into assemblies that resemble cartwheel centers. Point mutations are consistent with the notion that centriole formation in vivo depends on the interactions that define the self-assemblies observed here. Thus, these interactions are probably essential to the structural organization of cartwheel centers.

  6. Representing Personal Determinants in Causal Structures.

    Science.gov (United States)

    Bandura, Albert

    1984-01-01

    Responds to Staddon's critique of the author's earlier article and addresses issues raised by Staddon's (1984) alternative models of causality. The author argues that it is not the formalizability of causal processes that is the issue but whether cognitive determinants of behavior are reducible to past stimulus inputs in causal structures.…

  7. Virtuous organization: A structural equation modeling approach

    Directory of Open Access Journals (Sweden)

    Majid Zamahani

    2013-02-01

    Full Text Available For years, the idea of virtue was unfavorable among researchers and virtues were traditionally considered as culture-specific, relativistic and they were supposed to be associated with social conservatism, religious or moral dogmatism, and scientific irrelevance. Virtue and virtuousness have been recently considered seriously among organizational researchers. The proposed study of this paper examines the relationships between leadership, organizational culture, human resource, structure and processes, care for community and virtuous organization. Structural equation modeling is employed to investigate the effects of each variable on other components. The data used in this study consists of questionnaire responses from employees in Payam e Noor University in Yazd province. A total of 250 questionnaires were sent out and a total of 211 valid responses were received. Our results have revealed that all the five variables have positive and significant impacts on virtuous organization. Among the five variables, organizational culture has the most direct impact (0.80 and human resource has the most total impact (0.844 on virtuous organization.

  8. Structural determinants in the bulk heterojunction.

    Science.gov (United States)

    Acocella, Angela; Höfinger, Siegfried; Haunschmid, Ernst; Pop, Sergiu C; Narumi, Tetsu; Yasuoka, Kenji; Yasui, Masato; Zerbetto, Francesco

    2018-02-21

    Photovoltaics is one of the key areas in renewable energy research with remarkable progress made every year. Here we consider the case of a photoactive material and study its structural composition and the resulting consequences for the fundamental processes driving solar energy conversion. A multiscale approach is used to characterize essential molecular properties of the light-absorbing layer. A selection of bulk-representative pairs of donor/acceptor molecules is extracted from the molecular dynamics simulation of the bulk heterojunction and analyzed at increasing levels of detail. Significantly increased ground state energies together with an array of additional structural characteristics are identified that all point towards an auxiliary role of the material's structural organization in mediating charge-transfer and -separation. Mechanistic studies of the type presented here can provide important insights into fundamental principles governing solar energy conversion in next-generation photovoltaic devices.

  9. [Classification of organisms and structuralism in biology].

    Science.gov (United States)

    Vasil'eva, L I

    2001-01-01

    Structuralism in biology is the oldest trend oriented to the search for natural "laws of forms" comparable with laws of growth of crystal, was revived at the end of 20th century on the basis of structuralist thought in socio-humanitarian sciences. The development of principal ideas of the linguistic structuralism in some aspects is similar to that of biological systematics, especially concerning the relationships between "system" and "evolution". However, apart from this general similarity, biological structuralism is strongly focused on familiar problems of the origin of diversity in nature. In their striving for the renovation of existing views, biological structuralists oppose the neo-darwinism emphasizing the existence of "law of forms", that are independent on heredity and genetic "determinism". The trend to develop so-called "rational taxonomy" is also characteristic of biological structuralism but this attempt failed being connected neither with Darwin's historicism nor with Plato's typology.

  10. Human and organization factors: engineering operating safety into offshore structures

    International Nuclear Information System (INIS)

    Bea, Robert G.

    1998-01-01

    History indicates clearly that the safety of offshore structures is determined primarily by the humans and organizations responsible for these structures during their design, construction, operation, maintenance, and decommissioning. If the safety of offshore structures is to be preserved and improved, then attention of engineers should focus on to how to improve the reliability of the offshore structure 'system,' including the people that come into contact with the structure during its life-cycle. This article reviews and discusss concepts and engineering approaches that can be used in such efforts. Two specific human factor issues are addressed: (1) real-time management of safety during operations, and (2) development of a Safety Management Assessment System to help improve the safety of offshore structures

  11. Capital Structure Determinants and Governance Structure Variety in Franchising

    OpenAIRE

    Jiang, Tao

    2009-01-01

    textabstractThis thesis investigates two questions: the determinants of capital structure in franchising and its subsequent impact on the franchise financing decisions; and the efficient governance structure choice in franchising. We posit that firms franchise in order to benefit from the reduced franchisees’ operational risks by limiting the debt level, such that the franchisor can bear more debt and gain tax-deduction benefits. Specific hypotheses are based on various theories like resource...

  12. Methods for Determining Organic Matter and Colour in Water

    Directory of Open Access Journals (Sweden)

    Ramunė Albrektienė

    2011-02-01

    Full Text Available The article examines different methods for determining organic matter and colour in water. Most of organic compounds in water have a humic substance. These substances frequently form complexes with iron. Humic matter gives water a yellow-brownish colour. Water filtration through conventional sand filters does not remove colour and organic compounds, and therefore complicated water treatment methods shall be applied. The methods utilized for organic matter determination in water included research on total organic carbon, permanganate index and the bichromate number of UV absorption of 254 nm wave length. The obtained results showed the greatest dependence between water colour and permanganate index. However, UV adsorption could be used for organic matter determination during the operation of a water treatment plant and the start-up of plants as easy and fast methods.Article in Lithuanian

  13. Understanding Determinants of Organic Food Consumption: Turkey Example

    Directory of Open Access Journals (Sweden)

    Burcu İlter

    2016-08-01

    Full Text Available The demand for organic products is growing, however in Turkey although the interest to organic products has grown; the growth of demand is relatively low. So it is important for producers of organic products to understand who the organic customers are, and what are their attitudes and behaviors regarding organic food products as well as why people do not prefer them. This is the main aim of this article. This study presents the results of a survey regarding consumer perceptions of organic foods in Turkey. The survey was conducted to determine consumer attitudes towards organic foods and the reasons for consumption or non-consumption of organic foods. A total of 882 consumers that makes food shopping for their families, living in İzmir participated the research. The results of the survey revealed that health issue is an important consideration in the consumption of organic products, however respondents stated that they find organic products expensive and hard to find everywhere, and they have some doubts about the reliability of the organic foods. Also five types of behaviour regarding organic food consumption behavior have been identified. The findings have practical implications especially for governments. More support and education should be given to organic producers so that supply of organic food products would increase, and there should be strict control on those products as to reduce consumers’ negative attitudes.

  14. Determination of hydrogen isotope composition in organic compounds

    International Nuclear Information System (INIS)

    Ordzhonikidze, K.G.; Parulava, L.P.; Vakhaniya, G.V.; Tarielashvili, V.O.

    1989-01-01

    method for determination of hydrogen isotope composition just in organic compounds using mass-spectrometer of the second class is suggested. The method enables to determine atomic fraction of hydrogen without multiplet separation. The accuracy of determination of deuterium atomic fraction in acetone in 1-99% range was equal to 3-0.2% respectively

  15. Simultaneous determination of protein structure and dynamics

    DEFF Research Database (Denmark)

    Lindorff-Larsen, Kresten; Best, Robert B.; DePristo, M. A.

    2005-01-01

    at the atomic level about the structural and dynamical features of proteins-with the ability of molecular dynamics simulations to explore a wide range of protein conformations. We illustrate the method for human ubiquitin in solution and find that there is considerable conformational heterogeneity throughout......We present a protocol for the experimental determination of ensembles of protein conformations that represent simultaneously the native structure and its associated dynamics. The procedure combines the strengths of nuclear magnetic resonance spectroscopy-for obtaining experimental information...... the protein structure. The interior atoms of the protein are tightly packed in each individual conformation that contributes to the ensemble but their overall behaviour can be described as having a significant degree of liquid-like character. The protocol is completely general and should lead to significant...

  16. Determinants and Management Outcomes of Pelvic Organ Prolapse ...

    African Journals Online (AJOL)

    Conclusion: The incidence of pelvic organ prolapse in this study was 6.5% and the leading determinants of pelvic organ prolapse were multiparity, menopause, chronic increase in IAP and advanced age. Most were lost to follow-up and a lesser proportion was offered conservative management. Early presentation of women ...

  17. Personal determinants of organic food consumption: a review

    OpenAIRE

    Aertsens, Joris; Verbeke, Wim; Mondelaers, Koen; Van Huylenbroeck, Guido

    2009-01-01

    Purpose - A lot of literature is available that discusses personal determinants of organic food consumption. However different models and determinants are used in the literature. This paper aims to provide an overview, within a framework linking Schwartz' values theory and the theory of planned behaviour (TPB). Also it seeks to focus on the importance of affective attitude, emotions, personal norm, involvement and uncertainty related to organic food consumption. Design/methodology/approac...

  18. High Resolution Powder Diffraction and Structure Determination

    International Nuclear Information System (INIS)

    Cox, D. E.

    1999-01-01

    It is clear that high-resolution synchrotrons X-ray powder diffraction is a very powerful and convenient tool for material characterization and structure determination. Most investigations to date have been carried out under ambient conditions and have focused on structure solution and refinement. The application of high-resolution techniques to increasingly complex structures will certainly represent an important part of future studies, and it has been seen how ab initio solution of structures with perhaps 100 atoms in the asymmetric unit is within the realms of possibility. However, the ease with which temperature-dependence measurements can be made combined with improvements in the technology of position-sensitive detectors will undoubtedly stimulate precise in situ structural studies of phase transitions and related phenomena. One challenge in this area will be to develop high-resolution techniques for ultra-high pressure investigations in diamond anvil cells. This will require highly focused beams and very precise collimation in front of the cell down to dimensions of 50 (micro)m or less. Anomalous scattering offers many interesting possibilities as well. As a means of enhancing scattering contrast it has applications not only to the determination of cation distribution in mixed systems such as the superconducting oxides discussed in Section 9.5.3, but also to the location of specific cations in partially occupied sites, such as the extra-framework positions in zeolites, for example. Another possible application is to provide phasing information for ab initio structure solution. Finally, the precise determination of f as a function of energy through an absorption edge can provide useful information about cation oxidation states, particularly in conjunction with XANES data. In contrast to many experiments at a synchrotron facility, powder diffraction is a relatively simple and user-friendly technique, and most of the procedures and software for data analysis

  19. Organization structure. Main activities of the Division

    International Nuclear Information System (INIS)

    2008-01-01

    In this chapter the organization structure as well as main activities of the Division for radiation safety, NPP decommissioning and radioactive waste management are presented. This Division of the VUJE, a.s. consists of the following sections and departments: Section for economic and technical services; Section for radiation protection of employees; Department for management of emergency situations and risk assessment; Department for implementation of nuclear power facilities decommissioning and RAW management; Department for personnel and environmental dosimetry; Department for preparation of NPP decommissioning; Department for RAW treatment technologies; Department for chemical regimes and physico-chemical analyses; Department for management of nuclear power facilities decommissioning and RAW management. Main activities of this Division are presented.

  20. Macromolecular structure determination in the post-genome era

    CERN Document Server

    Kuhn, P

    2001-01-01

    Recent advances in genetics, molecular biology and crystallographic instrumentation and methodology have led to a revolution in the field of Structural Molecular Biology (SMB). These combined advances have paved the way to a more complete and detailed understanding of the biological macromolecules that make up an organism, both in terms of their individual functions and also the interactions between them. In this paper we describe a large-scale, genomic approach to the three-dimensional structure determination of macromolecules and their complexes, using high-throughput methodology to streamline all aspects of the process. This task requires the development of automated high-intensity synchrotron beam lines for X-ray diffraction data collection from single crystal samples. Furthermore, these beam lines must be operated within a sophisticated software and hardware environment, which is capable of delivering a completely automated structure determination pipeline. The SMB resource at SSRL is developing a system...

  1. Determining the coating speed limitations for organic photovoltaic inks

    DEFF Research Database (Denmark)

    Jakubka, Florian; Heyder, Madeleine; Machui, Florian

    2013-01-01

    To determine the output capability of present organic photovoltaic (OPV) materials, it is important to know the theoretical maximum coating speeds of the used semiconductor formulations. Here, we present a comprehensive investigation of the coating stability window of several prototype organic...... semiconductor inks relevant for organic solar cells. The coating stability window was first determined experimentally by a sheet to sheet coater at velocities of up to 10 m/min. A numerical simulation model based on the Coating Window Suite 2010 software was established to give insight into the coating...

  2. Determinants of attitude and buying intention of organic milk

    Directory of Open Access Journals (Sweden)

    Ivica Faletar

    2016-01-01

    Full Text Available The consumption of organic milk is increasing rapidly. However, the behaviour of organic milk consumers is still not enough investigated. The purpose of this study was to determine variables which influence the attitude towards organic milk consumption, as well as variables which influence the buying intention of organic milk. Thereat, factors such as positive opinion toward organic milk and food related lifestyle, as well as level of trust in home as in EU organic food label, objective knowledge and gender of respondents showed to have a significant influence on organic milk buying intention. More precisely, a significant and positive influence on buying intention of organic milk was observed considering the belief in positive aspects of organic milk, subjective knowledge, objective knowledge, and attitude towards buying organic milk. According to the results of this study recommendations for marketing practice and especially for communication policy might be created. Communication directed to female population should use classic advertising based on functional information, while the one directed to male population should use more emotional advertising. By using classic advertising education of consumers should be performed in order to promote benefits of organic milk in regards to conventional milk.

  3. Language structure is partly determined by social structure.

    Directory of Open Access Journals (Sweden)

    Gary Lupyan

    Full Text Available BACKGROUND: Languages differ greatly both in their syntactic and morphological systems and in the social environments in which they exist. We challenge the view that language grammars are unrelated to social environments in which they are learned and used. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a statistical analysis of >2,000 languages using a combination of demographic sources and the World Atlas of Language Structures--a database of structural language properties. We found strong relationships between linguistic factors related to morphological complexity, and demographic/socio-historical factors such as the number of language users, geographic spread, and degree of language contact. The analyses suggest that languages spoken by large groups have simpler inflectional morphology than languages spoken by smaller groups as measured on a variety of factors such as case systems and complexity of conjugations. Additionally, languages spoken by large groups are much more likely to use lexical strategies in place of inflectional morphology to encode evidentiality, negation, aspect, and possession. Our findings indicate that just as biological organisms are shaped by ecological niches, language structures appear to adapt to the environment (niche in which they are being learned and used. As adults learn a language, features that are difficult for them to acquire, are less likely to be passed on to subsequent learners. Languages used for communication in large groups that include adult learners appear to have been subjected to such selection. Conversely, the morphological complexity common to languages used in small groups increases redundancy which may facilitate language learning by infants. CONCLUSIONS/SIGNIFICANCE: We hypothesize that language structures are subjected to different evolutionary pressures in different social environments. Just as biological organisms are shaped by ecological niches, language structures appear to adapt to the

  4. The Determinants of Organic Vegetable Purchasing in Jabodetabek Region, Indonesia

    Science.gov (United States)

    Slamet, Alim Setiawan; Nakayasu, Akira; Bai, Hu

    2016-01-01

    Over the last few years, the global market of organic vegetables has grown. This is due to increased consumer concern regarding environmental and health issues, especially for food products. This study aims to examine factors that influence consumer behavior in purchasing organic vegetables. In this study, data were obtained from household surveys conducted in the Jabodetabek region (Greater Jakarta) from February to March 2015. Descriptive analysis, factor analysis, and a binary logit model were used to analyze the data. Subsequently, the results show that consumers with fewer family members and have a higher income, and are price tolerant, are more likely to purchase organic vegetables. Meanwhile, female consumers are less likely to buy organic vegetables. Another important finding is that positive attitude towards organic products, safety and health, environmental concerns, as well as degree of trust in organic attributes, are the determinants of organic vegetable purchasing among consumers. Therefore, based on the study results, the following recommendations are needed for organic vegetable development in Indonesia: (a) implementing an appropriate pricing strategy; (b) encouraging organic labeling and certification for vegetables; and (c) intensively promoting organic food with respect to consumers’ motives and concerns on health, safety, as well as environmental sustainability. PMID:28231181

  5. The Determinants of Organic Vegetable Purchasing in Jabodetabek Region, Indonesia

    Directory of Open Access Journals (Sweden)

    Alim Setiawan Slamet

    2016-12-01

    Full Text Available Over the last few years, the global market of organic vegetables has grown. This is due to increased consumer concern regarding environmental and health issues, especially for food products. This study aims to examine factors that influence consumer behavior in purchasing organic vegetables. In this study, data were obtained from household surveys conducted in the Jabodetabek region (Greater Jakarta from February to March 2015. Descriptive analysis, factor analysis, and a binary logit model were used to analyze the data. Subsequently, the results show that consumers with fewer family members and have a higher income, and are price tolerant, are more likely to purchase organic vegetables. Meanwhile, female consumers are less likely to buy organic vegetables. Another important finding is that positive attitude towards organic products, safety and health, environmental concerns, as well as degree of trust in organic attributes, are the determinants of organic vegetable purchasing among consumers. Therefore, based on the study results, the following recommendations are needed for organic vegetable development in Indonesia: (a implementing an appropriate pricing strategy; (b encouraging organic labeling and certification for vegetables; and (c intensively promoting organic food with respect to consumers’ motives and concerns on health, safety, as well as environmental sustainability.

  6. The Determinants of Organic Vegetable Purchasing in Jabodetabek Region, Indonesia.

    Science.gov (United States)

    Slamet, Alim Setiawan; Nakayasu, Akira; Bai, Hu

    2016-12-07

    Over the last few years, the global market of organic vegetables has grown. This is due to increased consumer concern regarding environmental and health issues, especially for food products. This study aims to examine factors that influence consumer behavior in purchasing organic vegetables. In this study, data were obtained from household surveys conducted in the Jabodetabek region (Greater Jakarta) from February to March 2015. Descriptive analysis, factor analysis, and a binary logit model were used to analyze the data. Subsequently, the results show that consumers with fewer family members and have a higher income, and are price tolerant, are more likely to purchase organic vegetables. Meanwhile, female consumers are less likely to buy organic vegetables. Another important finding is that positive attitude towards organic products, safety and health, environmental concerns, as well as degree of trust in organic attributes, are the determinants of organic vegetable purchasing among consumers. Therefore, based on the study results, the following recommendations are needed for organic vegetable development in Indonesia: (a) implementing an appropriate pricing strategy; (b) encouraging organic labeling and certification for vegetables; and (c) intensively promoting organic food with respect to consumers' motives and concerns on health, safety, as well as environmental sustainability.

  7. Macromolecular structure determination in the post-genome era

    International Nuclear Information System (INIS)

    Kuhn, P.; Soltis, S.M.

    2001-01-01

    Recent advances in genetics, molecular biology and crystallographic instrumentation and methodology have led to a revolution in the field of Structural Molecular Biology (SMB). These combined advances have paved the way to a more complete and detailed understanding of the biological macromolecules that make up an organism, both in terms of their individual functions and also the interactions between them. In this paper we describe a large-scale, genomic approach to the three-dimensional structure determination of macromolecules and their complexes, using high-throughput methodology to streamline all aspects of the process. This task requires the development of automated high-intensity synchrotron beam lines for X-ray diffraction data collection from single crystal samples. Furthermore, these beam lines must be operated within a sophisticated software and hardware environment, which is capable of delivering a completely automated structure determination pipeline. The SMB resource at SSRL is developing a system for the structure determination steps of this process, starting with the initial characterization of the frozen sample, followed by data collection, data reduction, phase determination, and model building. This paper focuses on the data collection elements of this high-throughput system

  8. Determination of organic compounds in water using ultraviolet LED

    Science.gov (United States)

    Kim, Chihoon; Ji, Taeksoo; Eom, Joo Beom

    2018-04-01

    This paper describes a method of detecting organic compounds in water using an ultraviolet LED (280 nm) spectroscopy system and a photodetector. The LED spectroscopy system showed a high correlation between the concentration of the prepared potassium hydrogen phthalate and that calculated by multiple linear regression, indicating an adjusted coefficient of determination ranging from 0.953-0.993. In addition, a comparison between the performance of the spectroscopy system and the total organic carbon analyzer indicated that the difference in concentration was small. Based on the close correlation between the spectroscopy and photodetector absorbance values, organic measurement with a photodetector could be configured for monitoring.

  9. Structure determination by X-ray crystallography

    CERN Document Server

    Ladd, M F C

    1977-01-01

    Crystallography may be described as the science of the structure of materi­ als, using this word in its widest sense, and its ramifications are apparent over a broad front of current scientific endeavor. It is not surprising, therefore, to find that most universities offer some aspects of crystallography in their undergraduate courses in the physical sciences. It is the principal aim of this book to present an introduction to structure determination by X-ray crystal­ lography that is appropriate mainly to both final-year undergraduate studies in crystallography, chemistry, and chemical physics, and introductory post­ graduate work in this area of crystallography. We believe that the book will be of interest in other disciplines, such as physics, metallurgy, biochemistry, and geology, where crystallography has an important part to play. In the space of one book, it is not possible either to cover all aspects of crystallography or to treat all the subject matter completely rigorously. In particular, certain ...

  10. Matrix Organizational Structure and Its Effects Upon Education Organizations.

    Science.gov (United States)

    Yates, James R.

    Applying matrix organizational structure to the organization of special education services is the focus of this paper. Beginning with a list of ways in which educational organizations differ from business or military organizations, the author warns that educators must be cautious when transferring organizational structures from other disciplines…

  11. An Improved Conceptually-Based Method for Analysis of Communication Network Structure of Large Complex Organizations.

    Science.gov (United States)

    Richards, William D., Jr.

    Previous methods for determining the communication structure of organizations work well for small or simple organizations, but are either inadequate or unwieldy for use with large complex organizations. An improved method uses a number of different measures and a series of successive approximations to order the communication matrix such that…

  12. Structuring an Efficient Organic Wheat Breeding Program

    Directory of Open Access Journals (Sweden)

    P. Stephen Baenziger

    2011-08-01

    Full Text Available Our long-term goal is to develop wheat cultivars that will improve the profitability and competitiveness of organic producers in Nebraska and the Northern Great Plains. Our approach is to select in early generations for highly heritable traits that are needed for both organic and conventional production (another breeding goal, followed by a targeted organic breeding effort with testing at two organic locations (each in a different ecological region beginning with the F6 generation. Yield analyses from replicated trials at two organic breeding sites and 7 conventional breeding sites from F6 through F12 nurseries revealed, using analyses of variance, biplots, and comparisons of selected lines that it is inappropriate to use data from conventional testing for making germplasm selections for organic production. Selecting and testing lines under organic production practices in different ecological regions was also needed and cultivar selections for organic production were different than those for conventional production. Modifications to this breeding protocol may include growing early generation bulks in an organic cropping system. In the future, our selection efforts should also focus on using state-of-the-art, non-transgenic breeding technologies (genomic selection, marker-assisted breeding, and high throughput phenotyping to synergistically improve organic and conventional wheat breeding.

  13. Methods of soil organic carbon determination in Brazilian savannah soils

    Directory of Open Access Journals (Sweden)

    Juliana Hiromi Sato

    2014-08-01

    Full Text Available Several methods exist for determining soil organic carbon, and each one has its own advantages and limitations. Consequently, a comparison of the experimental results obtained when these methods are employed is hampered, causing problems in the comparison of carbon stocks in soils. This study aimed at evaluating the analytical procedures used in the determination of carbon and their relationships with soil mineralogy and texture. Wet combustion methods, including Walkley-Black, Mebius and Colorimetric determination as well as dry combustion methods, such as Elemental and Gravimetric Analysis were used. Quantitative textural and mineralogical (kaolinite, goethite and gibbsite analyses were also carried out. The wet digestion methods underestimated the concentration of organic carbon, while the gravimetric method overestimated. Soil mineralogy interfered with the determination of carbon, with emphasis on the gravimetric method that was greatly influenced by gibbsite.

  14. The psichological peculiarity structure organization of pupils and students

    OpenAIRE

    N P Kirina

    2009-01-01

    The article considers age differences of the psychological structure of pupils and students organization baseol on the general-functional approach to studying the qualities of the personality, which gives an opportunity to study age pecularities of organization in detail.

  15. [Preliminary determination of organic pollutants in agricultural fertilizers].

    Science.gov (United States)

    Mo, Ce-hui; Li, Yun-hui; Cai, Quan-ying; Zeng, Qiao-yun; Wang, Bo-guang; Li, Hai-qin

    2005-05-01

    Organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) in agricultural fertilizers are new problem deserved more study. Eight kinds of organic pollutants including 43 compounds classified as US EPA priority pollutants in twenty one agricultural fertilizers which were universally used in China were determined by Gas chromatography-mass spectrum (GC-MS). Three kinds of organic pollutants including more than 5 compounds were detected in most fertilizers, composing mainly of phthalic acid esters (PAEs), nitrobenzenes (NBs) and polycyclic aromatic hydrocarbons (PAHs). There were 26 compounds detected in at least one fertilizer, five of them especially PAEs detected in most fertilizer and even in all fertilizers. Benzo(a)pyrene, a strongly carcinogenic compound was detected in two fertilizers. Higher concentrations of compounds were determined in those fertilizers such as multifunction compound fertilizers and coated fertilizers.

  16. Review on methods for determination of metallothioneins in aquatic organisms.

    Science.gov (United States)

    Shariati, Fatemeh; Shariati, Shahab

    2011-06-01

    One aspect of environmental degradation in coastal areas is pollution from toxic metals, which are persistent and are bioaccumulated by marine organisms, with serious public health implications. A conventional monitoring system of environmental metal pollution includes measuring the level of selected metals in the whole organism or in respective organs. However, measuring only the metal content in particular organs does not give information about its effect at the subcellular level. Therefore, the evaluation of biochemical biomarker metallothionein may be useful in assessing metal exposure and the prediction of potential detrimental effects induced by metal contamination. There are some methods for the determination of metallothioneins including spectrophotometric method, electrochemical methods, chromatography, saturation-based methods, immunological methods, electrophoresis, and RT-PCR. In this paper, different methods are discussed briefly and the comparison between them will be presented.

  17. Organization structure of a basic school of arts

    OpenAIRE

    Sinkulová, Iveta

    2012-01-01

    TITLE: Organization Structure of a Basic School of Arts AUTHOR: Iveta Sinkulová ABSTRACT: My bachelor thesis "Organization Structure of a Basic School of Arts" sets a goal to research which organization structures are applied at basic schools of arts, how the jobs of headmaster and heads of departments are incorporated into the Org Chart and which tasks are delegated to them in terms of the management of teaching process. The first thing performed was descriptive research. Then the work of de...

  18. [Levels of bone mineral matrix organization and the mechanisms determining parameters of its formation].

    Science.gov (United States)

    Avrunin, A S; Tikhilov, R M; Abolin, A B; Shcherbak, I G

    2005-01-01

    Authors suggest to regard bone mineral matrix as the four-level structure. The first level is represented by an internal structure of a mineral, the second--by mineral morphological structure, the third--by coplanar association of minerals, and the fourth--by macroassociation of minerals in a single complex inside each bone. The most probable mechanisms determining stability of reproduction of mineral matrix parameters on each of these levels are shown. As a result of their functioning, the variants of bone mineral matrix structures are formed that are the programmed reflection of specificity of the given site of organic structures.

  19. Novel Structuring Routines for Organic Photovoltaics

    OpenAIRE

    Meier, Robert

    2012-01-01

    Organic photovoltaic devices are promising candidates for a future energy production at low-costs. In the framework of this thesis, fundamental aspects of organic solar cells based on different blend systems were investigated. X-ray scattering revealed a strong dependency of the inner film morphology of such devices on the layer thickness and the film composition. Applying optical methods, an enhanced photochemical degradation of blend films upon UV-irradiation was observed if ...

  20. Scale and structure of capitated physician organizations in California.

    Science.gov (United States)

    Rosenthal, M B; Frank, R G; Buchanan, J L; Epstein, A M

    2001-01-01

    Physician organizations in California broke new ground in the 1980s by accepting capitated contracts and taking on utilization management functions. In this paper we present new data that document the scale, structure, and vertical affiliations of physician organizations that accept capitation in California. We provide information on capitated enrollment, the share of revenue derived by physician organizations from capitation contracts, and the scope of risk sharing with health maintenance organizations (HMOs). Capitation contracts and risk sharing dominate payment arrangements with HMOs. Physician organizations appear to have responded to capitation by affiliating with hospitals and management companies, adopting hybrid organizational structures, and consolidating into larger entities.

  1. Demand structure and willingness to pay for organic dairy products

    DEFF Research Database (Denmark)

    Smed, Sinne

    2005-01-01

    This paper analyses if the introduction of a new and “low fat” organic variety of fluid milk has any effect on consumers’ valuation of organic milk in general and can rewind the stagnating trend in the demand for organic milk. In order to analyse this, the consumers’ purchasing structure was anal......This paper analyses if the introduction of a new and “low fat” organic variety of fluid milk has any effect on consumers’ valuation of organic milk in general and can rewind the stagnating trend in the demand for organic milk. In order to analyse this, the consumers’ purchasing structure...... was analysed and it was found that consumers first chose between different types of milk and secondly, decided of whether this milk was organic or conventional. Elasticities indicated a greater temporary flexibility in the demand structure and a permanent change of substitution patterns through...

  2. Integral Design workshops: organization, structure and testing

    NARCIS (Netherlands)

    Zeiler, W.; Savanovic, P.

    2010-01-01

    The purpose of this paper is to achieve an understanding of design activities in the context of building design. The starting point is an overview of design research and design methodology. From the insights gained by this analysis of design in this specific context, we present an ‘organization

  3. The Temporal Organization of Syllabic Structure

    Science.gov (United States)

    Shaw, Jason A.

    2010-01-01

    This dissertation develops analytical tools which enable rigorous evaluation of competing syllabic parses on the basis of temporal patterns in speech production data. The data come from the articulographic tracking of fleshpoints on target speech organs, e.g., tongue, lips, jaw, in experiments with native speakers of American English and Moroccan…

  4. Determination of organ doses and effective doses in radiooncology

    International Nuclear Information System (INIS)

    Roth, J.; Martinez, A.E.

    2007-01-01

    Background and Purpose: With an increasing chance of success in radiooncology, it is necessary to estimate the risk from radiation scatter to areas outside the target volume. The cancer risk from a radiation treatment can be estimated from the organ doses, allowing a somewhat limited effective dose to be estimated and compared. Material and Methods: The doses of the radiation-sensitive organs outside the target volume can be estimated with the aid of the PC program PERIDOSE developed by van der Giessen. The effective doses are determined according to the concept of ICRP, whereby the target volume and the associated organs related to it are not taken into consideration. Results: Organ doses outside the target volume are generally < 1% of the dose in the target volume. In some cases, however, they can be as high as 3%. The effective doses during radiotherapy are between 60 and 900 mSv, depending upon the specific target volume, the applied treatment technique, and the given dose in the ICRU point. Conclusion: For the estimation of the radiation risk, organ doses in radiooncology can be calculated with the aid of the PC program PERIDOSE. While evaluating the radiation risk after ICRP, for the calculation of the effective dose, the advanced age of many patients has to be considered to prevent that, e.g., the high gonad doses do not overestimate the effective dose. (orig.)

  5. From Virtual Organization to E-Business: Transformational Structuration

    OpenAIRE

    James J. Lee; Bandula Jayatilaka; Ben B. Kim; Ted E. Lee; Pairin Katerattanakul; Soongoo Hong

    2010-01-01

    This article shows how the technical hype of 1990s has been transformed into the e-business organizations at the beginning of the 21st century. The authors took an interpretive stance in this study, grounded theory, and investigated the ontology of virtual organization by the metaphorical analysis. The metaphorical analysis adopted in this study provides the analytical power to conceptualize the social structure of virtual organization in the context of structuration theory with the process o...

  6. Structural organization of Cobeae scandens Cav. nectaries

    OpenAIRE

    Mashkovska S.; Likhanov A.; Kliuvadenko A.

    2012-01-01

    It has ascertained, that Cobea scandens Cav., which introducted in the National botanic garden of M.M. Grishka NAN of Ukraine, has secretory tissues, which develop and function normally. In anatomical structure of C. scandens nectaries five structure- functional areas were founded. In the cells of secretory area a lot of RNA and proteins were detected. Intrastaminal nectaries have many common morpho-anatomical features with stamens. It is support of M. Dawson opinion (see Takhtajan 1966) abou...

  7. Synthesis and Structural Determination of Temocapril Sulfoxide Hydrochlorides

    International Nuclear Information System (INIS)

    Seong, Seok Bong; Moon, Jong Taik; Kim, Jung Ahn; Choo, Dong Joon; Lee, Jae Yeol

    2012-01-01

    Impurity (or related substance) control in pharmaceutical products is a primary goal of drug development. Stringent international regulatory requirements have been in place for several years as outlined in the International Conference on Harmonization (ICH) Guidelines Q3A (R), Q3B (R) and Q3C. According to ICH guidelines, impurities associated with the manufacture of a drug substance, also known as an active pharmaceutical ingredient (API), are classified into the following categories: (1) organic impurities (process and drug-related); (2) inorganic impurities (3) residual solvents. Many potential impurities result from the API manufacturing process including starting materials, isomers, intermediates, reagents, solvents, catalysts and reaction by-products. These potential impurities should be investigated to determine process control mechanisms for their removal and the need for specification controls at appropriate points in the process. The suggested structures of the impurities can be synthesized and will provide the final evidence for their structures, previously determined by spectroscopic methods. Therefore it is essential to know the structure of these impurities in the bulk drug in order to alter the reaction condition and to reduce the quantity of impurity to an acceptable level. Isolation, identification and quantification of impurities help the pharmaceutical company to obtain a pure substance with less toxicity and safety in drug therapy

  8. Structure and organization of heteromeric AMPA-type glutamate receptors.

    Science.gov (United States)

    Herguedas, Beatriz; García-Nafría, Javier; Cais, Ondrej; Fernández-Leiro, Rafael; Krieger, James; Ho, Hinze; Greger, Ingo H

    2016-04-29

    AMPA-type glutamate receptors (AMPARs), which are central mediators of rapid neurotransmission and synaptic plasticity, predominantly exist as heteromers of the subunits GluA1 to GluA4. Here we report the first AMPAR heteromer structures, which deviate substantially from existing GluA2 homomer structures. Crystal structures of the GluA2/3 and GluA2/4 N-terminal domains reveal a novel compact conformation with an alternating arrangement of the four subunits around a central axis. This organization is confirmed by cysteine cross-linking in full-length receptors, and it permitted us to determine the structure of an intact GluA2/3 receptor by cryogenic electron microscopy. Two models in the ligand-free state, at resolutions of 8.25 and 10.3 angstroms, exhibit substantial vertical compression and close associations between domain layers, reminiscent of N-methyl-D-aspartate receptors. Model 1 resembles a resting state and model 2 a desensitized state, thus providing snapshots of gating transitions in the nominal absence of ligand. Our data reveal organizational features of heteromeric AMPARs and provide a framework to decipher AMPAR architecture and signaling. Copyright © 2016, American Association for the Advancement of Science.

  9. Structure Property Relationships in Organic Conjugated Systems

    OpenAIRE

    O'Neill, Luke; Lynch, Patrick; McNamara, Mary

    2005-01-01

    A series of π conjugated oligomers were studied by absorption and photoluminescence spectroscopy. A linear relationship between the positioning of the absorption and photoluminescence maxima plotted against inverse conjugation length is observed. The relationships are in good agreement with the simple particle in a box method, one of the earliest descriptions of the properties of one-dimensional organic molecules. In addition to the electronic transition energies, it was observed that the Sto...

  10. PLAN FOR PERFORMANCE ADMINISTRATION IN PYRAMIDAL STRUCTURE ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Domingo Alarcón Ortiz

    2013-11-01

    Full Text Available Performance administration has become a current strategy in evaluating management within organizations, but its implementation often lacks an action plan, resulting from the valuation of climate and leadership styles embedded in the culture of the organization. This paper proposes a model action plan for performance management, which has been implemented, executed and evaluated in pyramidal organizational structure organizations where a diagnosis of the cultural climate and leadership styles recurring in the organization have been previously made.

  11. determination of verticality of reservoir engineering structure

    African Journals Online (AJOL)

    user

    applications is 3D survey and management of oil and gas facilities and other engineering structures. This recent .... also affect ground water contamination. 2. VERTICALITY ...... The soil, water and concrete in a Reservoir at the foundation bed ...

  12. DETERMINANTS OF FINANCIAL STRUCTURE OF GREEK COMPANIES

    Directory of Open Access Journals (Sweden)

    Gargalis PANAGIOTIS

    2016-06-01

    Full Text Available Capital structure is essential for the survival, growth and performance of a firm. There has been a growing interest worldwide in identifying the factors associated with debt leverage. This article aims to investigate the factors affecting the capital structure of companies listed on the Athens Stock Exchange (ASE. The data set used is composed of indicators reflecting the financial position and performance of 40 firms listed on the ASE in 2014. Using a regression model we estimate in what extent the financial structure of companies is affected by performance indicators and other specific factors like the field of activity or the size of the firms. The results obtained show an important influence of share of tangible assets in total assets of the company on the financial leverage, as main variable selected in order to reflect the capital structure of Greek companies.

  13. Structural organization of Cobeae scandens Cav. nectaries

    Directory of Open Access Journals (Sweden)

    A.F. Likhanov

    2012-03-01

    Full Text Available It has ascertained, that Cobea scandens Cav., which introducted in the National botanic garden of M.M. Grishka NAN of Ukraine, has secretory tissues, which develop and function normally. In anatomical structure of C. scandens nectaries five structure- functional areas were founded. In the cells of secretory area a lot of RNA and proteins were detected. Intrastaminal nectaries have many common morpho-anatomical features with stamens. It is support of M. Dawson opinion (see Takhtajan 1966 about staminal origin of C. scandens nectaries.

  14. Determination of total organic phosphorus in samples of mineral soils

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1962-01-01

    Full Text Available In this paper some observations on the estimation of organic phosphorus in mineral soils are reported. The fact is emphasized that the accuracy of all the methods available is relatively poor. Usually, there are no reasons to pay attention to differences less than about 20 ppm. of organic P. Analyses performed on 345 samples of Finnish mineral soils by the extraction method of MEHTA et. al. (10 and by a simple procedure adopted by the author (successive extractions with 4 N H2SO4 and 0.5 N NaOH at room temperature in the ratio of 1 to 100 gave, on the average, equal results. It seemed to be likely that the MEHTA method removed the organic phosphorus more completely than did the less vigorous method, but in the former the partial hydrolysis of organic phosphorus compounds tends to be higher than in the latter. An attempt was made to find out whether the differences between the respective values for organic phosphorus obtained by an ignition method and the simple extraction method could be connected with any characteristics of the soil. No correlation or only a low correlation coefficient could be calculated between the difference in the results of these two methods and e. g. the pH-value, the content of clay, organic carbon, aluminium and iron soluble in Tamm’s acid oxalate, the indicator of the phosphate sorption capacity, or the »Fe-bound» inorganic phosphorus, respectively. The absolute difference tended to increase with an increase in the content of organic phosphorus. For the 250 samples of surface soils analyzed, the ignition method gave values which were, on the average, about 50 ppm. higher than the results obtained by the extraction procedure. The corresponding difference for the 120 samples from deeper layers was about 20 ppm of organic P. The author recommends, for the present, the determination of the total soil organic phosphorus as an average of the results obtained by the ignition method and the extraction method.

  15. Quantitative Determination of Organic Semiconductor Microstructure from the Molecular to Device Scale

    KAUST Repository

    Rivnay, Jonathan

    2012-10-10

    A study was conducted to demonstrate quantitative determination of organic semiconductor microstructure from the molecular to device scale. The quantitative determination of organic semiconductor microstructure from the molecular to device scale was key to obtaining precise description of the molecular structure and microstructure of the materials of interest. This information combined with electrical characterization and modeling allowed for the establishment of general design rules to guide future rational design of materials and devices. Investigations revealed that a number and variety of defects were the largest contributors to the existence of disorder within a lattice, as organic semiconductor crystals were dominated by weak van der Waals bonding. Crystallite size, texture, and variations in structure due to spatial confinement and interfaces were also found to be relevant for transport of free charge carriers and bound excitonic species over distances that were important for device operation.

  16. Transport Gap and exciton binding energy determination in organic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Stefan; Schoell, Achim; Reinert, Friedrich; Umbach, Eberhard [University of Wuerzburg (Germany). Experimental Physics II; Casu, Benedetta [Inst. f. Physik. u. Theor. Chemie, Tuebingen (Germany)

    2008-07-01

    The transport gap of an organic semiconductor is defined as the energy difference between the HOMO and LUMO levels in the presence of a hole or electron, respectively, after relaxation has occurred. Its knowledge is mandatory for the optimisation of electronic devices based on these materials. UV photoelectron spectroscopy (UPS) and inverse photoelectron spectroscopy (IPES) are routinely applied to measure these molecular levels. However, the precise determination of the transport gap on the basis of the respective data is not an easy task. It involves fundamental questions about the properties of organic molecules and their condensates, about their reaction on the experimental probe, and on the evaluation of the spectroscopic data. In particular electronic relaxation processes, which occur on the time scale of the photo excitation, have to be considered adequately. We determined the transport gap for the organic semiconductors PTCDA, Alq3, DIP, CuPc, and PBI-H4. After careful data analysis and comparison to the respective values for the optical gap we obtain values for the exciton binding energies between 0.1-0.5 eV. This is considerably smaller than commonly believed and indicates a significant delocalisation of the excitonic charge over various molecular units.

  17. Science achievement determinants: factorial structure of family ...

    African Journals Online (AJOL)

    The family plays an important role in determining the academic achievement ... parents' assistance, expectation, and encouragement in their children's mathematics ... suggested that cultural upbringing is a strong factor contributing to the.

  18. Structure determination by X-ray crystallography

    CERN Document Server

    Ladd, M F C

    1995-01-01

    X-ray crystallography provides us with the most accurate picture we can get of atomic and molecular structures in crystals. It provides a hard bedrock of structural results in chemistry and in mineralogy. In biology, where the structures are not fully crystalline, it can still provide valuable results and, indeed, the impact here has been revolutionary. It is still an immense field for young workers, and no doubt will provide yet more striking develop­ ments of a major character. It does, however, require a wide range of intellectual application, and a considerable ability in many fields. This book will provide much help. It is a very straightforward and thorough guide to every aspect of the subject. The authors are experienced both as research workers themselves and as teachers of standing, and this is shown in their clarity of exposition. There are plenty of iliustrations and worked examples to aid the student to obtain a real grasp of the subject.

  19. Some structural determinants of melody recall.

    Science.gov (United States)

    Boltz, M

    1991-05-01

    Sophisticated musicians were asked to recall, using musical notation, a set of unfamiliar folk tunes that varied in rhythmic structure and referents of tonality. The results showed that memory was facilitated by tonic triad members marking phrase endings, but only when their presence was highlighted by a corresponding pattern of temporal accents. Conversely, recall significantly declined when tonal information was either absent or obscured by rhythmic structure. Error analyses further revealed that the retention of overall pitch contour and information at phrase ending points varied as a function of these manipulations. The results are discussed in terms of a framework that links the acts of perceiving and remembering to a common attentional scheme.

  20. Nitrosonium complexes of organic compounds. Structure and reactivity

    International Nuclear Information System (INIS)

    Borodkin, Gennady I; Shubin, Vyacheslav G

    2001-01-01

    Data on the structures and reactivities of nitrosonium complexes of organic compounds are systematised and generalised. The characteristic features of the electronic structure of the NO + cation are responsible for a wide structural variety of nitrosonium complexes. Reactions of nitrosonium complexes are described. The bibliography includes 172 references.

  1. The environmental structure to the interior of the organization

    International Nuclear Information System (INIS)

    Angel Sanint, Enrique

    1998-01-01

    The tasks to perform by any area are presented for the two basic types of environmental structure within the organization, function oriented and process oriented - based on that classification, advantages and disadvantages are identified for both structures. Finally, some additional coordination mechanisms are proposed in order to make the process oriented structure more flexible

  2. Organizations in America: Analyzing Their Structures and Human Resource Practices Based on the National Organizations Study.

    Science.gov (United States)

    Kalleberg, Arne L.; Knoke, David; Marsden, Peter V.; Spaeth, Joe L.

    In 1991 the National Organizations Study (NOS) surveyed a number of U.S. businesses about their structure, context, and personnel practices to produce a database for answering questions about social behavior in work organizations. This book presents the results of that survey. The study aimed to create a national database on organizations--based…

  3. Overcoming barriers to membrane protein structure determination

    NARCIS (Netherlands)

    Bill, Roslyn M.; Henderson, Peter J. F.; Iwata, So; Kunji, Edmund R. S.; Michel, Hartmut; Neutze, Richard; Newstead, Simon; Poolman, Bert; Tate, Christopher G.; Vogel, Horst

    After decades of slow progress, the pace of research on membrane protein structures is beginning to quicken thanks to various improvements in technology, including protein engineering and microfocus X-ray diffraction. Here we review these developments and, where possible, highlight generic new

  4. Structural determination and gynecological tumor diagnosis using ...

    African Journals Online (AJOL)

    covalent bonding patterns and branched structures. Studies have shown that changes in protein glycosylation at the cell surface during tumorigenesis are closely related to the occurrence and development of some cancers, including pancreatic cancer, mammary cancer, prostatic cancer, colon cancer, and gastric cancer [1].

  5. Determining the structure of Carbon-60

    International Nuclear Information System (INIS)

    Wif, D.

    1994-01-01

    Carbon-60 is the most stable and best known of the carbon cage structures known collectively as the fullerenes. It is a remarkable molecule that forms a fascinating solid. Although the molecular shape of C sub 6 sub 0 is familiar - it is simply the shape of a soccer ball with 12 pentagons and 20 hexagons - the manner in which it forms a crystal structure is by no means obvious. This talk will focus on the insights which neutron scattering at ISIS has brought to our understanding of solid C sub6 sub 0. At room temperature, the structure may be regarded as forming as essentially ideal cubic-close packed molecular b ubble-raft : each molecule is reorienting so rapidly that a time-averaged picture, over as little as a nanosecond, reveals a closely spherical shell of atomic density. At 260 K, a rather unusual structural transition occurs. The molecules order but still retain cubic symmetry. Although this may not appear to be a rather dramatic change, detailed considerations show that a profound transition has occurred that bears close similarities to a solid-liquid phase transition but in two dimensions. Below 260 K, reorientation still occurs but at a dramatically reduced rate as the temperature is lowered. Indeed at around 90 K, The reorientation is so slow that thermodynamic equilibrium cannot be achieved in a reasonable timescale an orientational glass transition occurs. Although the behaviour of solid C sub 6 sub 0 undergoes dramatic changes as a function of temperature, a coherent description has evolved in which neutron scattering plays a central role. Close analogies are to be found in the study of systems as diverse as solid H sub 2 and human-rhinovirus structures. These analogies and the central role played by neutron scattering at ISIS will be emphasised in this paper. 5 figs., 10 refs. (author)

  6. Simultaneous determination of inorganic and organic anions by ion chromatography

    International Nuclear Information System (INIS)

    Park, Yang Soon; Joe, Ki Soo; Han, Sun Ho; Park, Soon Dal; Choi, Kwang Soon

    1999-06-01

    Four methods were investigated for the simultaneous determination of several inorganic and organic anions in aqueous solution by ion chromatography. The first is two columns coupled system. The second is the gradient elution system with an anion exchange column. The third is the system with a mixed-mode stationary phase. The fourth is the system with an anion exchange column and the eluant of low conductivity without ion suppressor. The advantages and disadvantages of individual systems were discussed. The suitable methods were proposed for the application to the samples of the nuclear power industry and the environment. (author)

  7. Vascular structure determines pulmonary blood flow distribution

    Science.gov (United States)

    Hlastala, M. P.; Glenny, R. W.

    1999-01-01

    Scientific knowledge develops through the evolution of new concepts. This process is usually driven by new methodologies that provide observations not previously available. Understanding of pulmonary blood flow determinants advanced significantly in the 1960s and is now changing rapidly again, because of increased spatial resolution of regional pulmonary blood flow measurements.

  8. Uranium determination by UV-Vis spectrophotometry in organic matrix

    International Nuclear Information System (INIS)

    Iwaki, Leonardo E.O.; Silva, Ieda S.; Oliveira, Luis C.

    2013-01-01

    Concentrations of uranium in the process samples provide essential information required for nuclear process monitoring. A large number of techniques have been developed to allow uranium determination, but each technique possesses some advantages and disadvantages and cannot be applied without difficulty to all samples. The ultraviolet visible spectrophotometry (UV-Vis) is widely method used in analytical industrial processes due to its simplicity, rapidity, low costs, low generation of analytical waste, easy calibration and operation. In this study, we describe a simple and fast quantification method to determination of a high amount of uranium in organic phase (TBP/kerosene) using UV-Vis spectrophotometry. The process sample was analyzed in UV-Vis and compared with inductively coupled plasma optical emission spectrometry (ICP OES) showing similar results in both methods. The statistical tests (Student-t and Fischer) showed that the both techniques they are equivalent. (author)

  9. Structural hierarchy in flow-aligned hexagonally self-organized microphases with parallel polyelectrolytic structures

    NARCIS (Netherlands)

    Ruotsalainen, T; Torkkeli, M; Serimaa, R; Makela, T; Maki-Ontto, R; Ruokolainen, J; ten Brinke, G; Ikkala, O; Mäkelä, Tapio; Mäki-Ontto, Riikka

    2003-01-01

    We report a novel structural hierarchy where a flow-aligned hexagonal self-organized structure is combined with a polyelectrolytic self-organization on a smaller length scale and where the two structures are mutually parallel. Polystyrene-block-poly(4-vinylpyridine) (PS-block-P4VP) is selected with

  10. Determination of organ doses in radiographic imaging and diagnostic radiology

    International Nuclear Information System (INIS)

    Rathjen, M.

    1981-01-01

    Earlier publications on diagnostic radiation exposure commonly presented data on the gonadal dose. This emphasis on the genetic radiation risk is no longer valid in view of recent radiobiological findings; equal attention should be paid to the somatic radiation risk which is manifested by the induction of malignant neoplasms, e.g. in the lungs, red bone marrow, thyroid and female breast (ICRP 26). The permissible radiation doses for these organs and the gonals for routine diagnostic radiology are determined. A formula is established on the basis of terms from relevant publications (e.g. open-air dose, backscattering factor) and from the author's own measurements in an Alderson-Rando phantom (depth dose curves, dose decrements). The measurements were carried out using CaP 2 thermoluminescence dosemeters, and the organ doses for the various techniques of X-ray examination were calculated by computer. Calculations of this type will enable the radiologist to determine the patient exposure quickly and easily from the records kept according to Sect. 29 of the X-ray Ordinance. Experimental value from relevant publications are compared with the author's own results. (orig./HP) [de

  11. Three-Dimensional Structure Determination of Botulinum Toxin

    National Research Council Canada - National Science Library

    Stevens, Ray

    1997-01-01

    ...) Based on the structure of the neurotoxin, understand the toxins mechanism of action. We have accomplished the first goal of determining the three-dimensional structure of the 150 kD botulinum neurotoxin serotype...

  12. Three-Dimensional Structure Determination of Botulinum Toxin

    National Research Council Canada - National Science Library

    Stevens, Ray

    1998-01-01

    ...) Based on the structure of the neurotoxin, understand the toxins mechanism of action. We have accomplished the first goal of determining the three-dimensional structure of the 150 kD botulinum neurotoxin serotype...

  13. Organic bulk heterojunction photovoltaic structures: design, morphology and properties

    International Nuclear Information System (INIS)

    Bulavko, G V; Ishchenko, A A

    2014-01-01

    Main approaches to the design of organic bulk heterojunction photovoltaic structures are generalized and systematized. Novel photovoltaic materials based on fullerenes, organic dyes and related compounds, graphene, conjugated polymers and dendrimers are considered. The emphasis is placed on correlations between the chemical structure and properties of materials. The effect of morphology of the photoactive layer on the photovoltaic properties of devices is analyzed. Main methods of optimization of the photovoltaic properties are outlined. The bibliography includes 338 references

  14. cDNA structure, genomic organization and expression patterns of ...

    African Journals Online (AJOL)

    Visfatin was a newly identified adipocytokine, which was involved in various physiologic and pathologic processes of organisms. The cDNA structure, genomic organization and expression patterns of silver Prussian carp visfatin were described in this report. The silver Prussian carp visfatin cDNA cloned from the liver was ...

  15. Structural aspects of the evaluation of agent organizations

    NARCIS (Netherlands)

    Grossi, D.; Dignum, F.P.M.; Dignum, V.; Dastani, M.; Royakkers, L.M.M.; Noriega, P.; Vázquez-Salceda, J.; Boella, G.; Boissier, O.; Dignum, V.; Fornara, N.; Matson, E.

    2007-01-01

    A multi-agent system can be analyzed and specified as an organization consisting of roles and their relations. The performance of an organization depends on many factors among which the type of its organizational structure, i.e., the set of relations holding between its roles. This work focuses on

  16. Nuclear visions enhanced: chromatin structure, organization and dynamics

    OpenAIRE

    Meshorer, Eran; Herrmann, Harald; Raška, Ivan

    2011-01-01

    The EMBO Workshop on ‘Chromatin Structure, Organization and Dynamics' took place in April 2011 in Prague, Czech Republic. Participants presented data on the generation of models of the genome, working to correlate changes in the organization of chromatin with the functional state of the genome.

  17. Structural organization of DNA in chlorella viruses.

    Directory of Open Access Journals (Sweden)

    Timo Wulfmeyer

    Full Text Available Chlorella viruses have icosahedral capsids with an internal membrane enclosing their large dsDNA genomes and associated proteins. Their genomes are packaged in the particles with a predicted DNA density of ca. 0.2 bp nm(-3. Occasionally infection of an algal cell by an individual particle fails and the viral DNA is dynamically ejected from the capsid. This shows that the release of the DNA generates a force, which can aid in the transfer of the genome into the host in a successful infection. Imaging of ejected viral DNA indicates that it is intimately associated with proteins in a periodic fashion. The bulk of the protein particles detected by atomic force microscopy have a size of ∼60 kDa and two proteins (A278L and A282L of about this size are among 6 basic putative DNA binding proteins found in a proteomic analysis of DNA binding proteins packaged in the virion. A combination of fluorescence images of ejected DNA and a bioinformatics analysis of the DNA reveal periodic patterns in the viral DNA. The periodic distribution of GC rich regions in the genome provides potential binding sites for basic proteins. This DNA/protein aggregation could be responsible for the periodic concentration of fluorescently labeled DNA observed in ejected viral DNA. Collectively the data indicate that the large chlorella viruses have a DNA packaging strategy that differs from bacteriophages; it involves proteins and share similarities to that of chromatin structure in eukaryotes.

  18. The determinants of capital structure: evidence from Dutch panel data

    OpenAIRE

    Chen, Linda H.; Lensink, Robert; Sterken, Elmer

    1999-01-01

    This paper studies the determinants of capital structure choice of Dutch firms. Our main objective is to investigate whether and to what extent the main capital structure theories can explain capital structure choice of Dutch firms. A better understanding of the capital structure determinants in a rela-tively small yet open industrialized economy is essential not only for enrich-ing empirical studies in this field, but also for the purpose of cross country asset evaluation. By estimating a pa...

  19. How structure determines correlations in neuronal networks.

    Directory of Open Access Journals (Sweden)

    Volker Pernice

    2011-05-01

    Full Text Available Networks are becoming a ubiquitous metaphor for the understanding of complex biological systems, spanning the range between molecular signalling pathways, neural networks in the brain, and interacting species in a food web. In many models, we face an intricate interplay between the topology of the network and the dynamics of the system, which is generally very hard to disentangle. A dynamical feature that has been subject of intense research in various fields are correlations between the noisy activity of nodes in a network. We consider a class of systems, where discrete signals are sent along the links of the network. Such systems are of particular relevance in neuroscience, because they provide models for networks of neurons that use action potentials for communication. We study correlations in dynamic networks with arbitrary topology, assuming linear pulse coupling. With our novel approach, we are able to understand in detail how specific structural motifs affect pairwise correlations. Based on a power series decomposition of the covariance matrix, we describe the conditions under which very indirect interactions will have a pronounced effect on correlations and population dynamics. In random networks, we find that indirect interactions may lead to a broad distribution of activation levels with low average but highly variable correlations. This phenomenon is even more pronounced in networks with distance dependent connectivity. In contrast, networks with highly connected hubs or patchy connections often exhibit strong average correlations. Our results are particularly relevant in view of new experimental techniques that enable the parallel recording of spiking activity from a large number of neurons, an appropriate interpretation of which is hampered by the currently limited understanding of structure-dynamics relations in complex networks.

  20. Determining building interior structures using compressive sensing

    Science.gov (United States)

    Lagunas, Eva; Amin, Moeness G.; Ahmad, Fauzia; Nájar, Montse

    2013-04-01

    We consider imaging of the building interior structures using compressive sensing (CS) with applications to through-the-wall imaging and urban sensing. We consider a monostatic synthetic aperture radar imaging system employing stepped frequency waveform. The proposed approach exploits prior information of building construction practices to form an appropriate sparse representation of the building interior layout. We devise a dictionary of possible wall locations, which is consistent with the fact that interior walls are typically parallel or perpendicular to the front wall. The dictionary accounts for the dominant normal angle reflections from exterior and interior walls for the monostatic imaging system. CS is applied to a reduced set of observations to recover the true positions of the walls. Additional information about interior walls can be obtained using a dictionary of possible corner reflectors, which is the response of the junction of two walls. Supporting results based on simulation and laboratory experiments are provided. It is shown that the proposed sparsifying basis outperforms the conventional through-the-wall CS model, the wavelet sparsifying basis, and the block sparse model for building interior layout detection.

  1. Principles of disaster management lesson. 12: structuring organizations.

    Science.gov (United States)

    Cuny, F C

    2001-01-01

    This lesson discusses various structures for organizations that have functional roles in disaster responses, relief, and/or management activities. It distinguishes between pyramidal and matrix structures, and notes the advantages and disadvantages of each in relation to disasters. Span of control issues are dissected including the impact of the "P" factor on the performance of disaster managers and workers including its relationship to the coordination and control function. The development of a Table of Organization and how it relates to departmentalization within an organization also is provided.

  2. Microwave Determination of the Structure of Pyridine

    Energy Technology Data Exchange (ETDEWEB)

    Bak, B.; Hansen, L.; Rastrup-Andersen, J. [Chemical Laboratory of the University of Copenhagen, Copenhagen (Denmark)

    1954-12-15

    2‐, 3‐, and 4‐mono‐deutero‐pyridine have been prepared and the microwave spectra recorded. For each of the isotopic species 11—12 transitions (Q‐ and R‐branch lines) were localized, a number of which could be identified by their Stark effect. For all three species rotational constants of high precision were calculated. The material so provided in connection with known rotational constants for ordinary pyridine is insufficient for a complete determination of the ten geometrical parameters of the molecule. Seven models with a choice of C – H distances close to the correct value (1.075‐1.085 A) were considered one of which was shown to be consistent with electron‐diffraction work and current valence theory. In this model d(N – C(2)) = 1.340±0.005; d(C(2) – C(3)) = 1.390±0.005; d(C(3) – C(4)) = 1.400±0.005 A. The valence angles in the aromatic ring (starting with the C(6) – N – C(2) angle) are: 116° 42′; 124° 00′; 118° 36′; 118° 06′.

  3. Threedimensional imaging of organ structures by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Waters, W.; Smolorz, J.; Wellner, U.

    1985-01-01

    A simple method for threedimensional imaging of organ structures is presented. The method is based on a special acquisition mode in a nuclear resonance tomograph, exciting layers of 20 cm thickness at different angulations. The display is done by cinematography (which is usually used in nuclear cardiology) projecting the structures in a rotating movement. (orig.) [de

  4. Status quo and future research challenges on organic food quality determination with focus on laboratory methods.

    Science.gov (United States)

    Kahl, Johannes; Bodroza-Solarov, Marija; Busscher, Nicolaas; Hajslova, Jana; Kneifel, Wolfgang; Kokornaczyk, Maria Olga; van Ruth, Saskia; Schulzova, Vera; Stolz, Peter

    2014-10-01

    Organic food quality determination needs multi-dimensional evaluation tools. The main focus is on the authentication as an analytical verification of the certification process. New fingerprinting approaches such as ultra-performance liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry, direct analysis in real time-high-resolution mass spectrometry as well as crystallization with and without the presence of additives seem to be promising methods in terms of time of analysis and detecting organic system-related parameters. For further methodological development, a system approach is recommended, which also takes into account food structure aspects. Furthermore, the authentication of processed organic samples needs more consciousness, hence most of organic food is complex and processed. © 2013 Society of Chemical Industry.

  5. Determinants of information technology outsourcing among health maintenance organizations.

    Science.gov (United States)

    Wholey, D R; Padman, R; Hamer, R; Schwartz, S

    2001-09-01

    We analyze the determinants of HMO information technology outsourcing using two studies. Study 1 examines the effect of asset specificity on outsourcing for development and operation activities, using HMO specific fixed effects to control for differences between HMOs. Study 2 regresses the HMO specific fixed effects from Study 1, which measure an HMO's propensity to outsource, on HMO characteristics. The data comes from a 1995 InterStudy survey about information technology organization of HMOs. While HMOs split roughly equally in outsourcing information technology development activities, they are extremely unlikely to outsource the day-to-day operation of information systems. The greater an HMO's information technology capability and the complexity of information systems supported, the less likely is an HMO to outsource. While HMOs less than two years old, for-profit HMOs, local or Blue Cross-affiliated HMOs, and mixed HMOs are more likely to outsource, federally qualified HMOs are less likely to outsource. Policy and managerial implications for the adoption and diffusion of new ways of organizing information technology, such as application service providers (ASPs), are discussed.

  6. Determination of Volatile Organic Compounds in Selected Strains of Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Ivan Milovanović

    2015-01-01

    Full Text Available Microalgal biomass can be used in creating various functional food and feed products, but certain species of microalgae and cyanobacteria are known to produce various compounds causing off-flavour. In this work, we investigated selected cyanobacterial strains of Spirulina, Anabaena, and Nostoc genera originating from Serbia, with the aim of determining the chemical profile of volatile organic compounds produced by these organisms. Additionally, the influence of nitrogen level during growth on the production of volatile compounds was investigated for Nostoc and Anabaena strains. In addition, multivariate techniques, namely, principal component analysis (PCA and hierarchical cluster analysis (HCA, were used for making distinction among different microalgal strains. The results show that the main volatile compounds in these species are medium chain length alkanes, but other odorous compounds such as 2-methylisoborneol (0.51–4.48%, 2-pentylfuran (0.72–8.98%, β-cyclocitral (0.00–1.17%, and β-ionone (1.15–2.72% were also detected in the samples. Addition of nitrogen to growth medium was shown to negatively affect the production of 2-methylisoborneol, while geosmin was not detected in any of the analyzed samples, which indicates that the manipulation of growth conditions may be useful in reducing levels of some unwanted odor-causing components.

  7. Sensitive determination of nucleic acids using organic nanoparticle fluorescence probes

    Science.gov (United States)

    Zhou, Yunyou; Bian, Guirong; Wang, Leyu; Dong, Ling; Wang, Lun; Kan, Jian

    2005-06-01

    This paper describes the preparation of organic nanoparticles by reprecipitation method under sonication and vigorous stirring. Transmission electron microscopy (TEM) was used to characterize the size and size distribution of the luminescent nanoparticles. Their average diameter was about 25 nm with a size variation of ±18%. The fluorescence decay lifetime of the nanoparticles also was determined on a self-equipped fluorospectrometer with laser light source. The lifetime (˜0.09 μs) of nanoparticles is about three times long as that of the monomer. The nanoparticles were in abundant of hydrophilic groups, which increased their miscibility in aqueous solution. These organic nanoparticles have high photochemical stability, excellent resistance to chemical degradation and photodegradation, and a good fluorescence quantum yield (25%). The fluorescence can be efficiently quenched by nucleic acids. Based on the fluorescence quenching of nanoparticles, a fluorescence quenching method was developed for determination of microamounts of nucleic acids by using the nanoparticles as a new fluorescent probe. Under optimal conditions, maximum fluorescence quenching is produced, with maximum excitation and emission wavelengths of 345 and 402 nm, respectively. Under optimal conditions, the calibration graphs are linear over the range 0.4-19.0 μg ml -1 for calf thymus DNA (ct-DNA) and 0.3-19.0 μg ml -1 for fish sperm DNA (fs-DNA). The corresponding detection limits are 0.25 μg ml -1 for ct-DNA and 0.17 μg ml -1 for fs-DNA. The relative standard deviation of six replicate measurements is 1.3-2.1%. The method is simple, rapid and sensitive with wide linear range. The recovery and relative standard deviation are very satisfactory.

  8. 5 THE DETERMINANTS OF FINANCIAL STRUCTURE IN THE ...

    African Journals Online (AJOL)

    these authors showed that the presence of imperfections in the market ... impact of financial structure on firm value, several theoretical and ... structure of for-profit organizations (Fama and French, 2000; .... compared to large companies to face the pressures that are generated .... assets' accounting value or the sales.

  9. Determination of atomic cluster structure with cluster fusion algorithm

    DEFF Research Database (Denmark)

    Obolensky, Oleg I.; Solov'yov, Ilia; Solov'yov, Andrey V.

    2005-01-01

    We report an efficient scheme of global optimization, called cluster fusion algorithm, which has proved its reliability and high efficiency in determination of the structure of various atomic clusters.......We report an efficient scheme of global optimization, called cluster fusion algorithm, which has proved its reliability and high efficiency in determination of the structure of various atomic clusters....

  10. Structure of catalase determined by MicroED

    Science.gov (United States)

    Nannenga, Brent L; Shi, Dan; Hattne, Johan; Reyes, Francis E; Gonen, Tamir

    2014-01-01

    MicroED is a recently developed method that uses electron diffraction for structure determination from very small three-dimensional crystals of biological material. Previously we used a series of still diffraction patterns to determine the structure of lysozyme at 2.9 Å resolution with MicroED (Shi et al., 2013). Here we present the structure of bovine liver catalase determined from a single crystal at 3.2 Å resolution by MicroED. The data were collected by continuous rotation of the sample under constant exposure and were processed and refined using standard programs for X-ray crystallography. The ability of MicroED to determine the structure of bovine liver catalase, a protein that has long resisted atomic analysis by traditional electron crystallography, demonstrates the potential of this method for structure determination. DOI: http://dx.doi.org/10.7554/eLife.03600.001 PMID:25303172

  11. [Volunteer satisfaction: Internal structure and relationship with permanence in organizations].

    Science.gov (United States)

    Vecina Jiménez, M L; Chacón Fuertes, Fernando; Sueiro Abad, Manuel J

    2009-02-01

    Volunteer satisfaction: Internal structure and relationship with permanence in organizations. The concept of satisfaction is considered theoretically relevant in practically all the studies that have investigated the factors that influence the permanence of volunteer participation in organizations. However, the practical results are not conclusive, perhaps due to the wide range of ways in which the concept is understood and measured. The object of this study is: to analyse the internal structure of satisfaction and to verify its relationship with volunteer duration in organizations. The results of the factor analysis yield a three-factor structure: Satisfaction with the management of the organization, Satisfaction with the tasks, Satisfaction of motivations. The three factors allow us to differentiate between individuals who remain in the organization for a period of 12 consecutive months, and those who leave earlier. The results of structural equation model analysis show that the relationship between satisfaction and the length of time that volunteers stay with the organization is affected by the intention to remain.

  12. Interface Structure of MoO3 on Organic Semiconductors

    Science.gov (United States)

    White, Robin T.; Thibau, Emmanuel S.; Lu, Zheng-Hong

    2016-01-01

    We have systematically studied interface structure formed by vapor-phase deposition of typical transition metal oxide MoO3 on organic semiconductors. Eight organic hole transport materials have been used in this study. Ultraviolet photoelectron spectroscopy and X-ray photoelectron spectroscopy are used to measure the evolution of the physical, chemical and electronic structure of the interfaces at various stages of MoO3 deposition on these organic semiconductor surfaces. For the interface physical structure, it is found that MoO3 diffuses into the underlying organic layer, exhibiting a trend of increasing diffusion with decreasing molecular molar mass. For the interface chemical structure, new carbon and molybdenum core-level states are observed, as a result of interfacial electron transfer from organic semiconductor to MoO3. For the interface electronic structure, energy level alignment is observed in agreement with the universal energy level alignment rule of molecules on metal oxides, despite deposition order inversion. PMID:26880185

  13. Rapid and reliable protein structure determination via chemical shift threading.

    Science.gov (United States)

    Hafsa, Noor E; Berjanskii, Mark V; Arndt, David; Wishart, David S

    2018-01-01

    Protein structure determination using nuclear magnetic resonance (NMR) spectroscopy can be both time-consuming and labor intensive. Here we demonstrate how chemical shift threading can permit rapid, robust, and accurate protein structure determination using only chemical shift data. Threading is a relatively old bioinformatics technique that uses a combination of sequence information and predicted (or experimentally acquired) low-resolution structural data to generate high-resolution 3D protein structures. The key motivations behind using NMR chemical shifts for protein threading lie in the fact that they are easy to measure, they are available prior to 3D structure determination, and they contain vital structural information. The method we have developed uses not only sequence and chemical shift similarity but also chemical shift-derived secondary structure, shift-derived super-secondary structure, and shift-derived accessible surface area to generate a high quality protein structure regardless of the sequence similarity (or lack thereof) to a known structure already in the PDB. The method (called E-Thrifty) was found to be very fast (often chemical shift refinement, these results suggest that protein structure determination, using only NMR chemical shifts, is becoming increasingly practical and reliable. E-Thrifty is available as a web server at http://ethrifty.ca .

  14. Two-plane symmetry in the structural organization of man.

    Science.gov (United States)

    Ermolenko, A E

    2005-01-01

    Manifestations of symmetry in the human structural organization in ontogenesis and phylogenetic development are analysed. A concept of macrobiocrystalloid with inherent complex symmetry is proposed for the description of the human organism in its integrity. The symmetry can be characterized as two-plane radial (quadrilateral), where the planar symmetry is predominant while the layout of organs of radial symmetry is subordinated to it. Out of the two planes of symmetry (sagittal and horizontal), the sagittal plane is predominant: (a) the location of the organs is governed by two principles: in compliance with the symmetry planes and in compliance with the radial symmetry around cavities; (b) the location of the radial symmetry organs is also governed by the principle of two-plane symmetry; (c) out of the four antimeres of two-plane symmetry, two are paired while the other two have merged into one organ; (d) some organs which are antimeres relative to the horizontal plane are located at the cranial end of the organism (sensory organs, cerebrum-cerebellum, heart-spleen and others). The two-plane symmetry is formed by two mechanisms--(a) the impact of morphogenetic fields of the whole crystalloid organism during embriogenesis and (b) genetic mechanisms of the development of chromosomes having two-plane symmetry. When comparing mineral and biological entities we should consider not the whole immobile crystal but only the active superficial part of a growing or dissolving crystal, the interface between the crystal surface and the crystal-forming environment which directly controls crystal growth and adapts itself to it, as well as crystal feed stock expressed in the structure of concentration flows. The symmetry of the chromosome, of the embrion at the early stages of cell cleavage as well as of some organs and systems in their phylogenetic development is described.

  15. E-learning and the Educational Organizations Structure Reengineering (EOSR

    Directory of Open Access Journals (Sweden)

    Osama Alshara

    2007-06-01

    Full Text Available There are many calls for innovative learning methods that utilize advanced technologies. However, we will raise fundamental questions that look deep into the future of the educational organization. Can the educational institute survive without adapting learning technologies? Would the educational institute succeed in adapting new learning technologies without changing its organizational structure and processes? We claim that the answer to both questions is no. Our research will present the need for edu-cational institutes to incorporate learning technologies and focuses on the demand for the educational organization structure reengineering as a basic requirement for the suc-cess of incorporating learning technologies. Our study ex-plores the faculty requirements and policies and procedures of educational institutes in the UAE.The paper concludes with some discussions on findings from a case study of the need of educational organization struc-ture reengineering as a basic requirement for incorporating learning technologies.

  16. Progress in organic and physical chemistry structures and mechanisms

    CERN Document Server

    Zaikov, Gennady E; Lobanov, Anton V

    2013-01-01

    Progress in Organic and Physical Chemistry: Structures and Mechanisms provides a collection of new research in the field of organic and physical properties, including new research on: The physical principles of the conductivity of electrical conducting polymer compounds The dependence on constants of electromagnetic interactions upon electron spacial-energy characteristics Effects of chitosan molecultural weight on rehological behavior of chitosan modified nanoclay at hight hydrated state Bio-structural energy criteria of functional states in normal and pathological conditions Potentiometric study on the international between devalent cations and sodium carboxylates in aqueous solutions Structural characteristic changes in erythrocyte membranes of mice bearing Alzheimer's-like disease caused by the olfactory bulbetomy This volume is intended to provide an overview of new studies and research for engineers, faculty, researchers, and upper-level students in the field of organic and physical chemistry.

  17. Liposomes: structure, properties and methods of curative administration in organism

    Directory of Open Access Journals (Sweden)

    M. A. Kisyakova

    2010-07-01

    Full Text Available A review of data from scientific sources, devoted to problems of liposomes’ structure, properties and processes of formation was made. Advantages of liposomes used for medical purposes are shown. Methods of liposomes administration in an organism are characterised. Data on mechanisms of interaction between liposomes and cells, peculiarities of liposomes’ lipids composition and dependence of its tropism to definite organs and tissues are generalised.

  18. Determinants of consumer behavior related to organic foods.

    Science.gov (United States)

    Shepherd, Richard; Magnusson, Maria; Sjödén, Per-Olow

    2005-06-01

    There have been many studies of what influences consumers in their decisions to purchase or consume organic foods, mainly concerned with fresh organic foods. These show a discrepancy between attitudes and behavior with people being positive about organic foods but often not purchasing them. This discrepancy seems to be explained by the fact that consumers do not consider "organically produced" to be an important purchase criterion, that organic foods are not perceived to surpass conventional foods regarding taste and shelf life (two qualities rated to be of great importance), and because of the perceived premium prices of organic foods. In two Swedish studies, health benefits were demonstrated to be more strongly related to attitudes and behavior toward organic foods than were perceived environmental benefits. A new European Union (EU) project will investigate the influences on both fresh and processed organic foods and investigate the role of moral, ethical, and affective influences on choice across eight EU countries.

  19. De novo protein structure determination using sparse NMR data

    International Nuclear Information System (INIS)

    Bowers, Peter M.; Strauss, Charlie E.M.; Baker, David

    2000-01-01

    We describe a method for generating moderate to high-resolution protein structures using limited NMR data combined with the ab initio protein structure prediction method Rosetta. Peptide fragments are selected from proteins of known structure based on sequence similarity and consistency with chemical shift and NOE data. Models are built from these fragments by minimizing an energy function that favors hydrophobic burial, strand pairing, and satisfaction of NOE constraints. Models generated using this procedure with ∼1 NOE constraint per residue are in some cases closer to the corresponding X-ray structures than the published NMR solution structures. The method requires only the sparse constraints available during initial stages of NMR structure determination, and thus holds promise for increasing the speed with which protein solution structures can be determined

  20. Discerning Thermodynamic Basis of Self-Organization in Critical Zone Structure and Function

    Science.gov (United States)

    Richardson, M.; Kumar, P.

    2017-12-01

    Self-organization characterizes the spontaneous emergence of order. Self-organization in the Critical Zone, the region of Earth's skin from below the groundwater table to the top of the vegetation canopy, involves the interaction of biotic and abiotic processes occurring through a hierarchy of temporal and spatial scales. The self-organization is sustained through input of energy and material in an open system framework, and the resulting formations are called dissipative structures. Why do these local states of organization form and how are they thermodynamically favorable? We hypothesize that structure formation is linked to energy conversion and matter throughput rates across driving gradients. Furthermore, we predict that structures in the Critical Zone evolve based on local availability of nutrients, water, and energy. By considering ecosystems as open thermodynamic systems, we model and study the throughput signatures on short times scales to determine origins and characteristics of ecosystem structure. This diagnostic approach allows us to use fluxes of matter and energy to understand the thermodynamic drivers of the system. By classifying the fluxes and dynamics in a system, we can identify patterns to determine the thermodynamic drivers for organized states. Additionally, studying the partitioning of nutrients, water, and energy throughout ecosystems through dissipative structures will help identify reasons for structure shapes and how these shapes impact major Critical Zone functions.

  1. Cryo-EM Structure Determination Using Segmented Helical Image Reconstruction.

    Science.gov (United States)

    Fromm, S A; Sachse, C

    2016-01-01

    Treating helices as single-particle-like segments followed by helical image reconstruction has become the method of choice for high-resolution structure determination of well-ordered helical viruses as well as flexible filaments. In this review, we will illustrate how the combination of latest hardware developments with optimized image processing routines have led to a series of near-atomic resolution structures of helical assemblies. Originally, the treatment of helices as a sequence of segments followed by Fourier-Bessel reconstruction revealed the potential to determine near-atomic resolution structures from helical specimens. In the meantime, real-space image processing of helices in a stack of single particles was developed and enabled the structure determination of specimens that resisted classical Fourier helical reconstruction and also facilitated high-resolution structure determination. Despite the progress in real-space analysis, the combination of Fourier and real-space processing is still commonly used to better estimate the symmetry parameters as the imposition of the correct helical symmetry is essential for high-resolution structure determination. Recent hardware advancement by the introduction of direct electron detectors has significantly enhanced the image quality and together with improved image processing procedures has made segmented helical reconstruction a very productive cryo-EM structure determination method. © 2016 Elsevier Inc. All rights reserved.

  2. Organic superconductors: A current overview, synthesis, structure and theory

    International Nuclear Information System (INIS)

    Wang, H.H.; Beno, M.A.; Carlson, K.D.; Geiser, U.; Kini, A.M.; Williams, J.M.

    1990-01-01

    To date, four types of crystal packing motifs (β, θ, κ and α) are known to lead to superconductivity in the BEDT-TTF based materials, where BEDT-TTF is bis(ethylenedithio)tetrathiafulvalene. The syntheses, crystal structures, physical properties and band electronic structures of these materials will be reviewed. Recent progress made in the oxygen containing analogue, BEDO-TTF [bis(ethylenedioxo)tetrathiofulvalene] will be presented. The implication and future prospect of organic superconductors will be discussed

  3. Structures formation through self-organized accretion on cosmic strings

    International Nuclear Information System (INIS)

    Murdzek, R.

    2009-01-01

    In this paper, we shall show that the formation of structures through accretion by a cosmic string is driven by a natural feed-back mechanism: a part of the energy radiated by accretions creates a pressure on the accretion disk itself. This phenomenon leads to a nonlinear evolution of the accretion process. Thus, the formation of structures results as a consequence of a self-organized growth of the accreting central object.

  4. One-dimensional nonlinear self-organized structures in dusty plasmas

    International Nuclear Information System (INIS)

    Tsytovich, V.N.

    2000-01-01

    Dusty plasmas, which are open systems, can form stable one-dimensional self-organized structures. Absorption of plasma by dust particles results in the plasma flux from the plasma regions where the dust is absent. It is found that, in a one-dimensional dust layer, this flux is completely determined by the number of dust particles per unit area of the layer surface. This number determines all of the other parameters of the steady-state dust structure; in particular, it determines the spatial distributions of the dust density, dust charge, electron and ion densities, and ion drift velocity. In these structures, a force and electrostatic balance is established that ensures the necessary conditions for confining the dust and plasma particles in the structure. The equilibrium structures exist only for subthermal ion flow velocities. This criterion determines the maximum possible number of dust particles per unit area in the steady-state structure. The structures have a universal thickness, and the dust density changes sharply at the edge of the structure. The structures with a size either less than or larger than the ion mean free path with respect to ion-neutral collisions, quasi-neutral and charged structures, and soliton- and anti-soliton-like structures are investigated. Laboratory experiments and observations in extraterrestrial plasma formation are discussed in relation to dust structures

  5. Quantitative Determination of Organic Semiconductor Microstructure from the Molecular to Device Scale

    KAUST Repository

    Rivnay, Jonathan; Mannsfeld, Stefan C. B.; Miller, Chad E.; Salleo, Alberto; Toney, Michael F.

    2012-01-01

    A study was conducted to demonstrate quantitative determination of organic semiconductor microstructure from the molecular to device scale. The quantitative determination of organic semiconductor microstructure from the molecular to device scale

  6. Molecular Determinants of Dissolved Organic Matter Reactivity in Lake Water

    Directory of Open Access Journals (Sweden)

    Alina Mostovaya

    2017-12-01

    Full Text Available Lakes in the boreal region have been recognized as the biogeochemical hotspots, yet many questions regarding the regulators of organic matter processing in these systems remain open. Molecular composition can be an important determinant of dissolved organic matter (DOM fate in freshwater systems, but many aspects of this relationship remain unclear due to the complexity of DOM and its interactions in the natural environment. Here, we combine ultrahigh resolution mass spectrometry (FT-ICR-MS with kinetic modeling of decay of >1,300 individual DOM molecular formulae identified by mass spectrometry, to evaluate the role of specific molecular characteristics in decomposition of lake water DOM. Our data is derived from a 4 months microbial decomposition experiment, carried out on water from three Swedish lakes, with the set-up including natural lake water, as well as the lake water pretreated with UV light. The relative decay rate of every molecular formula was estimated by fitting a single exponential model to the change in FT-ICR-MS signal intensities over decomposition time. We found a continuous range of exponential decay coefficients (kexp within different groups of compounds and show that for highly unsaturated and phenolic compounds the distribution of kexp was shifted toward the lowest values. Contrary to this general trend, plant-derived polyphenols and polycondensed aromatics were on average more reactive than compounds with an intermediate aromaticity. The decay rate of aromatic compounds increased with increasing nominal oxidation state of carbon, and molecular mass in some cases showed an inverse relationship with kexp in the UV-manipulated treatment. Further, we observe an increase in formulae-specific kexp as a result of the UV pretreatment. General trends in reactivity identified among major compound groups emphasize the importance of the intrinsic controllers of lake water DOM decay. However, we additionally indicate that each

  7. Near-unity mass accommodation coefficient of organic molecules of varying structure.

    Science.gov (United States)

    Julin, Jan; Winkler, Paul M; Donahue, Neil M; Wagner, Paul E; Riipinen, Ilona

    2014-10-21

    Atmospheric aerosol particles have a significant effect on global climate, air quality, and consequently human health. Condensation of organic vapors is a key process in the growth of nanometer-sized particles to climate relevant sizes. This growth is very sensitive to the mass accommodation coefficient α, a quantity describing the vapor uptake ability of the particles, but knowledge on α of atmospheric organics is lacking. In this work, we have determined α for four organic molecules with diverse structural properties: adipic acid, succinic acid, naphthalene, and nonane. The coefficients are studied using molecular dynamics simulations, complemented with expansion chamber measurements. Our results are consistent with α = 1 (indicating nearly perfect accommodation), regardless of the molecular structural properties, the phase state of the bulk condensed phase, or surface curvature. The results highlight the need for experimental techniques capable of resolving the internal structure of nanoparticles to better constrain the accommodation of atmospheric organics.

  8. Structural proteomics of minimal organisms: conservation ofprotein fold usage and evolutionary implications

    Energy Technology Data Exchange (ETDEWEB)

    Chandonia, John-Marc; Kim, Sung-Hou

    2006-03-15

    Background: Determining the complete repertoire of proteinstructures for all soluble, globular proteins in a single organism hasbeen one of the major goals of several structural genomics projects inrecent years. Results: We report that this goal has nearly been reachedfor several "minimal organisms"--parasites or symbionts with reducedgenomes--for which over 95 percent of the soluble, globular proteins maynow be assigned folds, overall 3-D backbone structures. We analyze thestructures of these proteins as they relate to cellular functions, andcompare conservation off old usage between functional categories. We alsocompare patterns in the conservation off olds among minimal organisms andthose observed between minimal organisms and other bacteria. Conclusion:We find that proteins performing essential cellular functions closelyrelated to transcription and translation exhibit a higher degree ofconservation in fold usage than proteins in other functional categories.Folds related to transcription and translation functional categories werealso over represented in minimal organisms compared to otherbacteria.

  9. Determinants of capital structure and financial crisis impact: evidence

    OpenAIRE

    Proença, Pedro Miguel Correia

    2012-01-01

    Mestrado em contabilidade The objectives of this empirical work are to investigate the determinants of Portuguese SMEs capital structure, evaluate whether and how the impacts of those determinants affect the debt ratios and examine the effects of financial crisis and industry on Portuguese SMEs capital structure. The sample used considers the period 2007-2010, resulting in 12.857 Portugues e SMEs per year observations. R...

  10. Supramolecular Assembly of Calcium Metal - Organic Frameworks with Structural Transformation

    Czech Academy of Sciences Publication Activity Database

    Liang, P.-Ch.; Liu, H.-K.; Yeh, Ch.-T.; Lin, Ch.-H.; Zima, Vítězslav

    2011-01-01

    Roč. 11, č. 3 (2011), 699-708 ISSN 1528-7483 R&D Projects: GA ČR GA203/08/0208 Institutional research plan: CEZ:AV0Z40500505 Keywords : metal - organic frameworks * calcium * structure Subject RIV: CA - Inorganic Chemistry Impact factor: 4.720, year: 2011

  11. 17 CFR 201.421 - Commission consideration of determinations by self-regulatory organizations.

    Science.gov (United States)

    2010-04-01

    ... determinations by self-regulatory organizations. 201.421 Section 201.421 Commodity and Securities Exchanges... Commission Review § 201.421 Commission consideration of determinations by self-regulatory organizations. (a..., order review of any determination by a self-regulatory organization that could be subject to an...

  12. Transaction cost determinants of credit governance structures of ...

    African Journals Online (AJOL)

    This paper explores transaction cost determinants of credit governance structures (CGS) of commercial banks in Tanzania. Descriptive statistics, linear regression model, binary and multinomial logistic regression models were employed for analysis. Findings revealed four modes of credit governance structures that are ...

  13. The relationship between family orientation, organization context, organization structure and firm performance

    OpenAIRE

    Joris Meijaard; Lorraine Uhlaner

    2004-01-01

    This study focuses on the prediction of three firm performance indicators, sales growth, innovation performance and profitability, on a sample of small and medium-sized firms in the Netherlands. Predictions from agency theory and the resource based view of organizations lead to alternate hypotheses regarding the direct and indirect effects of family ownership and management on firm performance. Other variables in the analysis include various organization structure variables including standard...

  14. The Determinants of Capital Structure: Some Evidence from Banks

    OpenAIRE

    Heider, Florian; Gropp, Reint

    2008-01-01

    This paper documents that standard cross-sectional determinants of firm leverage also apply to the capital structure of large banks in the United States and Europe. We find a remarkable consistency in sign, significance and economic magnitude. Like non-financial firms, banks appear to have stable capital structures at levels that are specific to each individual bank. The results suggest that capital requirements may only be of second-order importance for banks’ capital structures and confirm ...

  15. Organic-Inorganic Perovskites: Structural Versatility for Functional Materials Design.

    Science.gov (United States)

    Saparov, Bayrammurad; Mitzi, David B

    2016-04-13

    Although known since the late 19th century, organic-inorganic perovskites have recently received extraordinary research community attention because of their unique physical properties, which make them promising candidates for application in photovoltaic (PV) and related optoelectronic devices. This review will explore beyond the current focus on three-dimensional (3-D) lead(II) halide perovskites, to highlight the great chemical flexibility and outstanding potential of the broader class of 3-D and lower dimensional organic-based perovskite family for electronic, optical, and energy-based applications as well as fundamental research. The concept of a multifunctional organic-inorganic hybrid, in which the organic and inorganic structural components provide intentional, unique, and hopefully synergistic features to the compound, represents an important contemporary target.

  16. Consumer knowledge structures with regards to organic foods

    DEFF Research Database (Denmark)

    Bredahl, Lone; Thøgersen, John; Dean, Moira

    2004-01-01

    associated with self-relevant consequences do not appear to discriminate clearly among segments, however. Generally, organic origin has significant links to personal values among segments of adventurous, enthusiastic, hedonistic and eco-healthy food consumers while it appears a dysfunctional means......This paper presents results of an empirical study conducted among European consumers to explore consumer knowledge structures with regard to organic foods and to identify the beliefs and the attribute-to-value chains that discriminate best among different consumer segments. Using means-end chain...... theory as the theoretical basis, the objectives of the study were met through carrying out laddering interviews with consumers in Germany, Great Britain, Denmark and Spain, using a Food-Related Lifestyle (FRL) segment-based approach and interviewing both organic and non-organic consumers. Respondents...

  17. Labor Market Structure and Salary Determination among Professional Basketball Players.

    Science.gov (United States)

    Wallace, Michael

    1988-01-01

    The author investigates the labor market structure and determinants of salaries for professional basketball players. An expanded version of the resource perspective is used. A three-tiered model of labor market segmentation is revealed for professional basketball players, but other variables also are important in salary determination. (Author/CH)

  18. Denotational, Causal, and Operational Determinism in Event Structures

    NARCIS (Netherlands)

    Rensink, Arend; Kirchner, H.

    1996-01-01

    Determinism of labelled transition systems and trees is a concept of theoretical and practical importance. We study its generalisation to event structures. It turns out that the result depends on what characterising property of tree determinism one sets out to generalise. We present three distinct

  19. Denotational, Causal, and Operational Determinism in Event Structures

    NARCIS (Netherlands)

    Rensink, Arend

    Determinism is a theoretically and practically important concept in labelled transition systems and trees. We study its generalisation to event structures. It turns out that the result depends on what characterising property of tree determinism one sets out to generalise. We present three distinct

  20. Stability of material in dynamics of structural organization

    Directory of Open Access Journals (Sweden)

    Vyrovoy Valery

    2017-01-01

    Full Text Available Formation of the scientific ideology is based on the basic model of the structured medium and demands the formalization of the term «structure». The objects-systems are offered to be present in the form of models. It is shown that the mechanism of structure formation on the solid level where gravity prevails differs from mechanism of structure formation at the level where forces of interparticle interactions dominate. It is asserted that geometrical characteristics of products define conditions of the organization of its integral structure. Rather independent coexistence of various solid levels assumes spontaneous realization of various interconnected events which provides the wholeness and safe functioning of a construction-system.

  1. Integral membrane protein structure determination using pseudocontact shifts

    Energy Technology Data Exchange (ETDEWEB)

    Crick, Duncan J.; Wang, Jue X. [University of Cambridge, Department of Biochemistry (United Kingdom); Graham, Bim; Swarbrick, James D. [Monash University, Monash Institute of Pharmaceutical Sciences (Australia); Mott, Helen R.; Nietlispach, Daniel, E-mail: dn206@cam.ac.uk [University of Cambridge, Department of Biochemistry (United Kingdom)

    2015-04-15

    Obtaining enough experimental restraints can be a limiting factor in the NMR structure determination of larger proteins. This is particularly the case for large assemblies such as membrane proteins that have been solubilized in a membrane-mimicking environment. Whilst in such cases extensive deuteration strategies are regularly utilised with the aim to improve the spectral quality, these schemes often limit the number of NOEs obtainable, making complementary strategies highly beneficial for successful structure elucidation. Recently, lanthanide-induced pseudocontact shifts (PCSs) have been established as a structural tool for globular proteins. Here, we demonstrate that a PCS-based approach can be successfully applied for the structure determination of integral membrane proteins. Using the 7TM α-helical microbial receptor pSRII, we show that PCS-derived restraints from lanthanide binding tags attached to four different positions of the protein facilitate the backbone structure determination when combined with a limited set of NOEs. In contrast, the same set of NOEs fails to determine the correct 3D fold. The latter situation is frequently encountered in polytopical α-helical membrane proteins and a PCS approach is thus suitable even for this particularly challenging class of membrane proteins. The ease of measuring PCSs makes this an attractive route for structure determination of large membrane proteins in general.

  2. Structural determination of intact proteins using mass spectrometry

    Science.gov (United States)

    Kruppa, Gary [San Francisco, CA; Schoeniger, Joseph S [Oakland, CA; Young, Malin M [Livermore, CA

    2008-05-06

    The present invention relates to novel methods of determining the sequence and structure of proteins. Specifically, the present invention allows for the analysis of intact proteins within a mass spectrometer. Therefore, preparatory separations need not be performed prior to introducing a protein sample into the mass spectrometer. Also disclosed herein are new instrumental developments for enhancing the signal from the desired modified proteins, methods for producing controlled protein fragments in the mass spectrometer, eliminating complex microseparations, and protein preparatory chemical steps necessary for cross-linking based protein structure determination.Additionally, the preferred method of the present invention involves the determination of protein structures utilizing a top-down analysis of protein structures to search for covalent modifications. In the preferred method, intact proteins are ionized and fragmented within the mass spectrometer.

  3. BIRTHDAY CAKE ACTIVITY STRUCTURED ARRANGEMENT FOR HELPING CHILDREN DETERMINING QUANTITIES

    Directory of Open Access Journals (Sweden)

    Neni Mariana

    2010-07-01

    Full Text Available Few researches have been concerned about relation between children’s spatialthinking and number sense. Narrowing for this small research, we focused onone component of spatial thinking, that is structuring objects, and onecomponent of number senses, that is cardinality by determining quantities. Thisstudy focused on a design research that was conducted in Indonesia in which weinvestigated pre-school children’s (between 2 and 3.5 years old ability inmaking structured arrangement and their ability to determine the quantities bylooking at the arrangements. The result shows us that some of the children wereable to make such arrangement. However, the children found difficulties eitherto determine quantities from those arrangements or to compare some structuresto easily recognize number of objects.Keywords: structures, structured arrangement, cardinality DOI: http://dx.doi.org/10.22342/jme.1.1.790.53-70

  4. Energy group structure determination using particle swarm optimization

    International Nuclear Information System (INIS)

    Yi, Ce; Sjoden, Glenn

    2013-01-01

    Highlights: ► Particle swarm optimization is applied to determine broad group structure. ► A graph representation of the broad group structure problem is introduced. ► The approach is tested on a fuel-pin model. - Abstract: Multi-group theory is widely applied for the energy domain discretization when solving the Linear Boltzmann Equation. To reduce the computational cost, fine group cross libraries are often down-sampled into broad group cross section libraries. Cross section data collapsing generally involves two steps: Firstly, the broad group structure has to be determined; secondly, a weighting scheme is used to evaluate the broad cross section library based on the fine group cross section data and the broad group structure. A common scheme is to average the fine group cross section weighted by the fine group flux. Cross section collapsing techniques have been intensively researched. However, most studies use a pre-determined group structure, open based on experience, to divide the neutron energy spectrum into thermal, epi-thermal, fast, etc. energy range. In this paper, a swarm intelligence algorithm, particle swarm optimization (PSO), is applied to optimize the broad group structure. A graph representation of the broad group structure determination problem is introduced. And the swarm intelligence algorithm is used to solve the graph model. The effectiveness of the approach is demonstrated using a fuel-pin model

  5. A Task-Based Approach to Organization: Knowledge, Communication and Structure

    OpenAIRE

    Luis Garicano; Yanhui Wu

    2010-01-01

    We bridge a gap between organizational economics and strategy research by developing a task-based approach to analyze organizational knowledge, process and structure, and deriving testable implications for the relation between production and organizational structure. We argue that organization emerges to integrate disperse knowledge and to coordinate talent in production and is designed to complement the limitations of human ability. The complexity of the tasks undertaken determines the optim...

  6. Structured-gate organic field-effect transistors

    International Nuclear Information System (INIS)

    Aljada, Muhsen; Pandey, Ajay K; Velusamy, Marappan; Burn, Paul L; Meredith, Paul; Namdas, Ebinazar B

    2012-01-01

    We report the fabrication and electrical characteristics of structured-gate organic field-effect transistors consisting of a gate electrode patterned with three-dimensional pillars. The pillar gate electrode was over-coated with a gate dielectric (SiO 2 ) and solution processed organic semiconductors producing both unipolar p-type and bipolar behaviour. We show that this new structured-gate architecture delivers higher source-drain currents, higher gate capacitance per unit equivalent linear channel area, and enhanced charge injection (electrons and/or holes) versus the conventional planar structure in all modes of operation. For the bipolar field-effect transistor (FET) the maximum source-drain current enhancements in p- and n-channel mode were >600% and 28%, respectively, leading to p and n charge mobilities with the same order of magnitude. Thus, we have demonstrated that it is possible to use the FET architecture to manipulate and match carrier mobilities of material combinations where one charge carrier is normally dominant. Mobility matching is advantageous for creating organic logic circuit elements such as inverters and amplifiers. Hence, the method represents a facile and generic strategy for improving the performance of standard organic semiconductors as well as new materials and blends. (paper)

  7. Structured-gate organic field-effect transistors

    Science.gov (United States)

    Aljada, Muhsen; Pandey, Ajay K.; Velusamy, Marappan; Burn, Paul L.; Meredith, Paul; Namdas, Ebinazar B.

    2012-06-01

    We report the fabrication and electrical characteristics of structured-gate organic field-effect transistors consisting of a gate electrode patterned with three-dimensional pillars. The pillar gate electrode was over-coated with a gate dielectric (SiO2) and solution processed organic semiconductors producing both unipolar p-type and bipolar behaviour. We show that this new structured-gate architecture delivers higher source-drain currents, higher gate capacitance per unit equivalent linear channel area, and enhanced charge injection (electrons and/or holes) versus the conventional planar structure in all modes of operation. For the bipolar field-effect transistor (FET) the maximum source-drain current enhancements in p- and n-channel mode were >600% and 28%, respectively, leading to p and n charge mobilities with the same order of magnitude. Thus, we have demonstrated that it is possible to use the FET architecture to manipulate and match carrier mobilities of material combinations where one charge carrier is normally dominant. Mobility matching is advantageous for creating organic logic circuit elements such as inverters and amplifiers. Hence, the method represents a facile and generic strategy for improving the performance of standard organic semiconductors as well as new materials and blends.

  8. Development of XAFS Into a Structure Determination Technique

    Science.gov (United States)

    Stern, E. A.

    After the detection of diffraction of x-rays by M. Laue in 1912, the technique was soon applied to structure determination by Bragg within a year. On the other hand, although the edge steps in X-Ray absorption were discovered even earlier by Barkla and both the near edge (XANES) and extended X-Ray fine structure (EXAFS) past the edge were detected by 1929, it still took over 40 years to realize the structure information contained in this X-Ray absorption fine structure (XAFS). To understand this delay a brief historical review of the development of the scientific ideas that transformed XAFS into the premiere technique for local structure determination is given. The development includes both advances in theoretical understanding and calculational capabilities, and in experimental facilities, especially synchrotron radiation sources. The present state of the XAFS technique and its capabilities are summarized.

  9. Structures in plasmas and their self-organizations

    International Nuclear Information System (INIS)

    Yoshida, Zensho

    1989-01-01

    This paper is a concise review of the physics of structures. The progress of the structure theory was motivated by the appearances of many different ordered structures that are self-organized through spontaneous dynamics. For typical examples in plasma physics, cited are the MHD equilibria (Taylor relaxed state), the ion acoustic solitons, and the van Kampen modes of continuous-spectrum Langmuir waves. A static theory for the intrinsic structures is developed to clarify the basic difference between the classical orders and the self-organized structures. In linear models, an intrinsic structure is characterized by a singular spectrum of a certain eigenvalue problem. The Taylor relaxed state is characterized by the continuum of the point spectra of the rotational operator. The general MHD equilibrium is related to a nonlinear eigenvalue problem. The soliton is a nonlinear eigenfunction of the Helmholtz-type Bohm equation. The variational expression of an intrinsic structure is characterized by restrictive functionals, which in a dynamical theory, is related to selective conservations. The Taylor relaxed state is obtained by minimizing the magnetic-field energy with conserving the magnetic helicity. This selective dissipation occurs in the fluctuations of kink modes. The soliton is self-organized by the dissipation of the Hamiltonian with keeping the energy approximately constant. The principle of the selective dissipation is logically a generalization of the ergodic hypothesis for the classical order and could be proved in a rigorous way by analyzing the attractor of the dynamical systems, just as the proof the ergodic theorem is obtained by the time-asymptotic analysis of a class of semigroups. (J.P.N.) 85 refs

  10. Developmental changes in organization of structural brain networks.

    Science.gov (United States)

    Khundrakpam, Budhachandra S; Reid, Andrew; Brauer, Jens; Carbonell, Felix; Lewis, John; Ameis, Stephanie; Karama, Sherif; Lee, Junki; Chen, Zhang; Das, Samir; Evans, Alan C

    2013-09-01

    Recent findings from developmental neuroimaging studies suggest that the enhancement of cognitive processes during development may be the result of a fine-tuning of the structural and functional organization of brain with maturation. However, the details regarding the developmental trajectory of large-scale structural brain networks are not yet understood. Here, we used graph theory to examine developmental changes in the organization of structural brain networks in 203 normally growing children and adolescents. Structural brain networks were constructed using interregional correlations in cortical thickness for 4 age groups (early childhood: 4.8-8.4 year; late childhood: 8.5-11.3 year; early adolescence: 11.4-14.7 year; late adolescence: 14.8-18.3 year). Late childhood showed prominent changes in topological properties, specifically a significant reduction in local efficiency, modularity, and increased global efficiency, suggesting a shift of topological organization toward a more random configuration. An increase in number and span of distribution of connector hubs was found in this age group. Finally, inter-regional connectivity analysis and graph-theoretic measures indicated early maturation of primary sensorimotor regions and protracted development of higher order association and paralimbic regions. Our finding reveals a time window of plasticity occurring during late childhood which may accommodate crucial changes during puberty and the new developmental tasks that an adolescent faces.

  11. Integrin β4 Regulates Migratory Behavior of Keratinocytes by Determining Laminin-332 Organization*s

    Science.gov (United States)

    Sehgal, Bernd U.; DeBiase, Phillip J.; Matzno, Sumio; Chew, Teng-Leong; Claiborne, Jessica N.; Hopkinson, Susan B.; Russell, Alan; Marinkovich, M. Peter; Jones, Jonathan C. R.

    2010-01-01

    Whether α6β4 integrin regulates migration remains controversial. β4 integrin-deficient (JEB) keratinocytes display aberrant migration in that they move in circles, a behavior that mirrors the circular arrays of laminin (LM)-332 in their matrix. In contrast, wild-type keratinocytes and JEB keratinocytes, induced to express β4 integrin, assemble laminin-332 in linear tracks over which they migrate. Moreover, laminin-332-dependent migration of JEB keratinocytes along linear tracks is restored when cells are plated on wild-type keratinocyte matrix, whereas wild-type keratinocytes show rotation over circular arrays of laminn-332 in JEB keratinocyte matrix. The activities of Rac1 and the actin cytoskeleton-severing protein cofilin are low in JEB keratinocytes compared with wild-type cells but are rescued following expression of wild-type β4 integrin in JEB cells. Additionally, in wild-type keratinocytes Rac1 is complexed with α6β4 integrin. Moreover, Rac1 or cofilin inactivation induces wild-type keratinocytes to move in circles over rings of laminin-332 in their matrix. Together these data indicate that laminin-332 matrix organization is determined by the α6β4 integrin/actin cytoskeleton via Rac1/cofilin signaling. Furthermore, our results imply that the organizational state of laminin-332 is a key determinant of the motility behavior of keratinocytes, an essential element of skin wound healing and the successful invasion of epidermal-derived tumor cells. PMID:16973601

  12. Structure determination of organic compounds tables of spectral data

    CERN Document Server

    Pretsch, Ernö; Badertscher, Martin

    2009-01-01

    The fourth edition of this highly-successful, concise text contains twenty percent new data. Also included now are chapters on (19)F-NMR and (31)P-NMR as well as references to important Raman bands. Contains nearly 500 illustrations.

  13. Capital Structure Determinants of Small and Medium Enterprises in Croatia

    Directory of Open Access Journals (Sweden)

    Nataša Šarlija

    2016-09-01

    Full Text Available Most of the research about capital structure is focused towards two theories: trade off theory (TOT and pecking order theory (POT. The idea is to explore which theory works better in certain conditions and identify the key determinants that affect the capital structure of the company. However, in different countries different determinants with opposite relation to the leverage are found to be significant. Besides, most of the previous researches are oriented on listed companies. The aim of this paper is to analyse the capital structure of small and medium enterprises in Croatia through the analysis of the fundamental determinants of the capital structure. The research was conducted on a data sample of 500 SMEs in Croatia in the period of 2005–2011. On the unbalanced panel data set a linear regression is applied. Influence of determinants on leverage is estimated by a static panel model with random effect and with fixed effect estimation. Four capital structure determinants are analysed: growth, size, profitability and tangible assets. The results of this research support the pecking order theory confirming that SMEs in Croatia are primarily financed frominternally generated funds that affect profitability, growth, tangible assets and enterprise size.

  14. Organization, structure, and performance in the US nuclear power industry

    International Nuclear Information System (INIS)

    Lester, R.K.

    1986-01-01

    Several propositions are advanced concerning the effects of industry organization and structure on the economic performance of the American commercial nuclear power industry. Both the electric utility industry and the nuclear power plant supply industry are relatively high degree of horizontal disaggregation. The latter is also characterized by an absence of vertical integration. The impact of each of these factors on construction and operating performance is discussed. Evidence is presented suggesting that the combination of horizontal and vertical disaggregation in the industry has had a significant adverse effect on economic performance. The relationship between industrial structure and regulatory behavior is also discussed. 43 references, 4 figures, 9 tables

  15. On structure of some laminated crystals with organic molecules

    International Nuclear Information System (INIS)

    Volodina, G.F.; Ivanova, V.Ya.; Malinovskij, T.I.

    1982-01-01

    A survey is made of papers dealing with intercalation of organic molecules into crystals of dihalcogenides of some transition metals (TaS 2 , TiS 2 , NbS 2 , ZrS 2 , TaSe 2 ), variation of their structure and physical properties. Among the used intercalates ammonia, pyridine, aniline and other aromatic amines proved to be most satisfactory from the viewpoint of reaction rate and product stability. A possibility is discussed of intercalation into PbI 2 and CdI 2 crystals that are of the same structural type as dihalcogenides

  16. Conversion coefficients for determining organ doses in paediatric spine radiography

    Energy Technology Data Exchange (ETDEWEB)

    Seidenbusch, Michael; Schneider, Karl [Ludwig-Maximilians-University of Munich, Institute of Clinical Radiology - Paediatric Radiology, Muenchen (Germany)

    2014-04-15

    Knowledge of organ and effective doses achieved during paediatric x-ray examinations is an important prerequisite for assessment of radiation burden to the patient. Conversion coefficients for reconstruction of organ and effective doses from entrance doses for segmental spine radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients are provided regarding the Guidelines of Good Radiographic Technique of the European Commission. Using the personal computer program PCXMC developed by the Finnish Centre for Radiation and Nuclear Safety (Saeteilyturvakeskus STUK), conversion coefficients for conventional segmental spine radiographs were calculated performing Monte Carlo simulations in mathematical hermaphrodite phantom models describing patients of different ages. The clinical variation of beam collimation was taken into consideration by defining optimal and suboptimal radiation field settings. Conversion coefficients for the reconstruction of organ doses in about 40 organs and tissues from measured entrance doses during cervical, thoracic and lumbar spine radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients were calculated for the standard sagittal and lateral beam projections and the standard focus detector distance of 115 cm. The conversion coefficients presented may be used for organ dose assessments from entrance doses measured during spine radiographs of patients of all age groups and all field settings within the optimal and suboptimal standard field settings. (orig.)

  17. Advanced organic composite materials for aircraft structures: Future program

    Science.gov (United States)

    1987-01-01

    Revolutionary advances in structural materials have been responsible for revolutionary changes in all fields of engineering. These advances have had and are still having a significant impact on aircraft design and performance. Composites are engineered materials. Their properties are tailored through the use of a mix or blend of different constituents to maximize selected properties of strength and/or stiffness at reduced weights. More than 20 years have passed since the potentials of filamentary composite materials were identified. During the 1970s much lower cost carbon filaments became a reality and gradually designers turned from boron to carbon composites. Despite progress in this field, filamentary composites still have significant unfulfilled potential for increasing aircraft productivity; the rendering of advanced organic composite materials into production aircraft structures was disappointingly slow. Why this is and research and technology development actions that will assist in accelerating the application of advanced organic composites to production aircraft is discussed.

  18. Carotenoids Database: structures, chemical fingerprints and distribution among organisms.

    Science.gov (United States)

    Yabuzaki, Junko

    2017-01-01

    To promote understanding of how organisms are related via carotenoids, either evolutionarily or symbiotically, or in food chains through natural histories, we built the Carotenoids Database. This provides chemical information on 1117 natural carotenoids with 683 source organisms. For extracting organisms closely related through the biosynthesis of carotenoids, we offer a new similarity search system 'Search similar carotenoids' using our original chemical fingerprint 'Carotenoid DB Chemical Fingerprints'. These Carotenoid DB Chemical Fingerprints describe the chemical substructure and the modification details based upon International Union of Pure and Applied Chemistry (IUPAC) semi-systematic names of the carotenoids. The fingerprints also allow (i) easier prediction of six biological functions of carotenoids: provitamin A, membrane stabilizers, odorous substances, allelochemicals, antiproliferative activity and reverse MDR activity against cancer cells, (ii) easier classification of carotenoid structures, (iii) partial and exact structure searching and (iv) easier extraction of structural isomers and stereoisomers. We believe this to be the first attempt to establish fingerprints using the IUPAC semi-systematic names. For extracting close profiled organisms, we provide a new tool 'Search similar profiled organisms'. Our current statistics show some insights into natural history: carotenoids seem to have been spread largely by bacteria, as they produce C30, C40, C45 and C50 carotenoids, with the widest range of end groups, and they share a small portion of C40 carotenoids with eukaryotes. Archaea share an even smaller portion with eukaryotes. Eukaryotes then have evolved a considerable variety of C40 carotenoids. Considering carotenoids, eukaryotes seem more closely related to bacteria than to archaea aside from 16S rRNA lineage analysis. : http://carotenoiddb.jp. © The Author(s) 2017. Published by Oxford University Press.

  19. Determination of the Orbital Lineup at Reactive Organic Semiconductor Interfaces Using Photoemission Spectroscopy

    National Research Council Canada - National Science Library

    Schlaf, R; Merritt, C. D; Picciolo, L. C; Kafafi, Zakya H

    2001-01-01

    ... (XPS and UPS) measurements. The Gaq3 /Mg system is a prototypical model structure for organic electron/low work function electrode transporting materials interfaces found in organic light emitting diodes (OLED...

  20. In cellulo structure determination of a novel cypovirus polyhedrin

    International Nuclear Information System (INIS)

    Axford, Danny; Ji, Xiaoyun; Stuart, David I.; Sutton, Geoff

    2014-01-01

    The crystal structure of a previously unsolved type of cypovirus polyhedrin has been determined from data collected directly from frozen live insect cells. This work demonstrates that with the use of a microfocus synchrotron beam the structure of a novel viral polyhedrin could be successfully determined from microcrystals within cells, removing the preparatory step of sample isolation and maintaining a favourable biological environment. The data obtained are of high quality, comparable to that obtained from isolated crystals, and enabled a facile structure determination. A small but significant difference is observed between the unit-cell parameters and the mosaic spread of in cellulo and isolated crystals, suggesting that even these robust crystals are adversely affected by removal from the cell

  1. Birthday Cake Activity Structured Arrangement for Helping Children Determining Quantities

    Directory of Open Access Journals (Sweden)

    Neni Mariana

    2010-07-01

    Full Text Available Few researches have been concerned about relation between children’s spatial thinking and number sense. Narrowing for this small research, we focused on one component of spatial thinking, that is structuring objects, and one component of number senses, that is cardinality by determining quantities. This study focused on a design research that was conducted in Indonesia in which we investigated pre-school children’s (between 2 and 3.5 years old ability in making structured arrangement and their ability to determine the quantities by looking at the arrangements. The result shows us that some of the children were able to make such arrangement. However, the children found difficulties either to determine quantities from those arrangements or to compare some structures to easily recognize number of objects.

  2. Additive Manufacturing of Biomedical Constructs with Biomimetic Structural Organizations.

    Science.gov (United States)

    Li, Xiao; He, Jiankang; Zhang, Weijie; Jiang, Nan; Li, Dichen

    2016-11-09

    Additive manufacturing (AM), sometimes called three-dimensional (3D) printing, has attracted a lot of research interest and is presenting unprecedented opportunities in biomedical fields, because this technology enables the fabrication of biomedical constructs with great freedom and in high precision. An important strategy in AM of biomedical constructs is to mimic the structural organizations of natural biological organisms. This can be done by directly depositing cells and biomaterials, depositing biomaterial structures before seeding cells, or fabricating molds before casting biomaterials and cells. This review organizes the research advances of AM-based biomimetic biomedical constructs into three major directions: 3D constructs that mimic tubular and branched networks of vasculatures; 3D constructs that contains gradient interfaces between different tissues; and 3D constructs that have different cells positioned to create multicellular systems. Other recent advances are also highlighted, regarding the applications of AM for organs-on-chips, AM-based micro/nanostructures, and functional nanomaterials. Under this theme, multiple aspects of AM including imaging/characterization, material selection, design, and printing techniques are discussed. The outlook at the end of this review points out several possible research directions for the future.

  3. Metal-organic frameworks: structure, properties, methods of synthesis and characterization

    International Nuclear Information System (INIS)

    Butova, V V; Soldatov, M A; Guda, A A; Lomachenko, K A; Lamberti, C

    2016-01-01

    This review deals with key methods of synthesis and characterization of metal-organic frameworks (MOFs). The modular structure affords a wide variety of MOFs with different active metal sites and organic linkers. These compounds represent a new stage of development of porous materials in which the pore size and the active site structure can be modified within wide limits. The set of experimental methods considered in this review is sufficient for studying the short-range and long-range order of the MOF crystal structure, determining the morphology of samples and elucidating the processes that occur at the active metal site in the course of chemical reactions. The interest in metal-organic frameworks results, first of all, from their numerous possible applications, ranging from gas separation and storage to chemical reactions within the pores. The bibliography includes 362 references

  4. Nucleic acid helix structure determination from NMR proton chemical shifts

    Energy Technology Data Exchange (ETDEWEB)

    Werf, Ramon M. van der; Tessari, Marco; Wijmenga, Sybren S., E-mail: S.Wijmenga@science.ru.nl [Radboud University Nijmegen, Department of Biophysical Chemistry, Institute of Molecules and Materials (Netherlands)

    2013-06-15

    We present a method for de novo derivation of the three-dimensional helix structure of nucleic acids using non-exchangeable proton chemical shifts as sole source of experimental restraints. The method is called chemical shift de novo structure derivation protocol employing singular value decomposition (CHEOPS) and uses iterative singular value decomposition to optimize the structure in helix parameter space. The correct performance of CHEOPS and its range of application are established via an extensive set of structure derivations using either simulated or experimental chemical shifts as input. The simulated input data are used to assess in a defined manner the effect of errors or limitations in the input data on the derived structures. We find that the RNA helix parameters can be determined with high accuracy. We finally demonstrate via three deposited RNA structures that experimental proton chemical shifts suffice to derive RNA helix structures with high precision and accuracy. CHEOPS provides, subject to further development, new directions for high-resolution NMR structure determination of nucleic acids.

  5. 17 CFR 201.420 - Appeal of determinations by self-regulatory organizations.

    Science.gov (United States)

    2010-04-01

    ... self-regulatory organizations. 201.420 Section 201.420 Commodity and Securities Exchanges SECURITIES... Review § 201.420 Appeal of determinations by self-regulatory organizations. (a) Application for review... by a self-regulatory organization determination as to which a notice is required to be filed with the...

  6. Determinants of Capital Structure in Non-Financial Companies

    OpenAIRE

    Kühnhausen, Fabian; Stieber, Harald W.

    2014-01-01

    In this paper, we evaluate firm-, industry- and country-specific factors determining a firm's capital structure. The empirical validity of several capital structure theories has been ambiguous so far. We shed light on the main drivers of leverage and depict differences in industry and country characteristics. Using a short panel data set with a large cross-section, we are able to show that firm size, industry leverage, industry growth and tax shield positively affect leverage ratios, while pr...

  7. A study on determinants of capital structure in India

    Directory of Open Access Journals (Sweden)

    Anshu Handoo

    2014-09-01

    Full Text Available The paper identifies the most important determinants of capital structure of 870 listed Indian firms comprising both private sector companies and government companies for the period 2001–2010. Ten independent variables and three dependent variables have been tested using regression analysis. It has been concluded that factors such as profitability, growth, asset tangibility, size, cost of debt, tax rate, and debt serving capacity have significant impact on the leverage structure chosen by firms in the Indian context.

  8. Sulfated oligosaccharide structures, as determined by NMR techniques

    International Nuclear Information System (INIS)

    Noseda, M.D.; Duarte, M.E.R.; Tischer, C.A.; Gorin, P.A.J.; Cerezo, A.S.

    1997-01-01

    Carrageenans are sulfated polysaccharides, produced by red seaweeds (Rhodophyta), that have important biological and physico-chemical properties. Using partial autohydrolysis, we obtained sulfated oligosaccharides from a λ-carrageenan (Noseda and Cerezo, 1993). These oligosaccharides are valuable not only for the study of the structures of the parent carrageenans but also for their possible biological activities. In this work we determined the chemical structure of one of the sulfated oligosaccharides using 1D and 2D NMR techniques. (author)

  9. Determinants of Market Structure and the Airline Industry

    Science.gov (United States)

    Raduchel, W.

    1972-01-01

    The general economic determinants of market structure are outlined with special reference to the airline industry. Included are the following facets: absolute size of firms; distributions of firms by size; concentration; entry barriers; product and service differentiation; diversification; degrees of competition; vertical integration; market boundaries; and economies of scale. Also examined are the static and dynamic properties of market structure in terms of mergers, government policies, and economic growth conditions.

  10. Generative probabilistic models extend the scope of inferential structure determination

    DEFF Research Database (Denmark)

    Olsson, Simon; Boomsma, Wouter; Frellsen, Jes

    2011-01-01

    demonstrate that the use of generative probabilistic models instead of physical forcefields in the Bayesian formalism is not only conceptually attractive, but also improves precision and efficiency. Our results open new vistas for the use of sophisticated probabilistic models of biomolecular structure......Conventional methods for protein structure determination from NMR data rely on the ad hoc combination of physical forcefields and experimental data, along with heuristic determination of free parameters such as weight of experimental data relative to a physical forcefield. Recently, a theoretically...

  11. Rotational characterization of methyl methacrylate: Internal dynamics and structure determination

    Science.gov (United States)

    Herbers, Sven; Wachsmuth, Dennis; Obenchain, Daniel A.; Grabow, Jens-Uwe

    2018-01-01

    Rotational constants, Watson's S centrifugal distortion coefficients, and internal rotation parameters of the two most stable conformers of methyl methacrylate were retrieved from the microwave spectrum. Splittings of rotational energy levels were caused by two non equivalent methyl tops. Constraining the centrifugal distortion coefficients and internal rotation parameters to the values of the main isotopologues, the rotational constants of all single substituted 13C and 18O isotopologues were determined. From these rotational constants the substitution structures and semi-empirical zero point structures of both conformers were precisely determined.

  12. Organizational Structure as a Determinant of Job Burnout.

    Science.gov (United States)

    Bilal, Atif; Ahmed, Hafiz Mushtaq

    2017-03-01

    This exploratory study determined the impact of organizational structure, particularly participation in decision making, instrumental communication, formalization, integration, and promotional opportunity, on burnout among Pakistani pediatric nurses. Data were collected from pediatric nurses working for Punjab's largest state-run hospital. The findings revealed that participation in decision making, instrumental communication, and promotional opportunity prevented burnout. Formalization contributed to burnout but integration was not related to burnout. Quite interestingly, except for supervisory status, most control variables for this study were not significantly related to emotional burnout. Hence, the hypothesis that organizational structure is a determinant of job burnout was accepted.

  13. Structural Origins of Scintillation: Metal Organic Frameworks as a Nanolaboratory

    Science.gov (United States)

    2016-06-01

    adsorption of fluorphores within their pores, form exciplexes similar to those found in solution-based systems and can these serve as a tool to control the...selected due to their ability to form luminescent exciplexes with electron-accepting organic chromophores. Incorporation of these guests within the...and W2×(A4), exciplex , where W and A terms describe the peak weighting factors and amplitudes. The intensities were determined from the integrated

  14. Organic/metal interfaces. Electronic and structural properties

    Energy Technology Data Exchange (ETDEWEB)

    Duhm, Steffen

    2008-07-17

    This work addresses several important topics of the field of organic electronics. The focus lies on organic/metal interfaces, which exist in all organic electronic devices. Physical properties of such interfaces are crucial for device performance. Four main topics have been covered: (i) the impact of molecular orientation on the energy levels, (ii) energy level tuning with strong electron acceptors, (iii) the role of thermodynamic equilibrium at organic/ organic homo-interfaces and (iv) the correlation of interfacial electronic structure and bonding distance. To address these issues a broad experimental approach was necessary: mainly ultraviolet photoelectron spectroscopy was used, supported by X-ray photoelectron spectroscopy, metastable atom electron spectroscopy, X-ray diffraction and X-ray standing waves, to examine vacuum sublimed thin films of conjugated organic molecules (COMs) in ultrahigh vacuum. (i) A novel approach is presented to explain the phenomenon that the ionization energy in molecular assemblies is orientation dependent. It is demonstrated that this is due to a macroscopic impact of intramolecular dipoles on the ionization energy in molecular assemblies. Furthermore, the correlation of molecular orientation and conformation has been studied in detail for COMs on various substrates. (ii) A new approach was developed to tune hole injection barriers ({delta}{sub h}) at organic/metal interfaces by adsorbing a (sub-) monolayer of an organic electron acceptor on the metal electrode. Charge transfer from the metal to the acceptor leads to a chemisorbed layer, which reduces {delta}{sub h} to the COM overlayer. This concept was tested with three acceptors and a lowering of {delta}{sub h} of up to 1.2 eV could be observed. (iii) A transition from vacuum-level alignment to molecular level pinning at the homo-interface between a lying monolayer and standing multilayers of a COM was observed, which depended on the amount of a pre-deposited acceptor. The

  15. High-throughput determination of RNA structure by proximity ligation.

    Science.gov (United States)

    Ramani, Vijay; Qiu, Ruolan; Shendure, Jay

    2015-09-01

    We present an unbiased method to globally resolve RNA structures through pairwise contact measurements between interacting regions. RNA proximity ligation (RPL) uses proximity ligation of native RNA followed by deep sequencing to yield chimeric reads with ligation junctions in the vicinity of structurally proximate bases. We apply RPL in both baker's yeast (Saccharomyces cerevisiae) and human cells and generate contact probability maps for ribosomal and other abundant RNAs, including yeast snoRNAs, the RNA subunit of the signal recognition particle and the yeast U2 spliceosomal RNA homolog. RPL measurements correlate with established secondary structures for these RNA molecules, including stem-loop structures and long-range pseudoknots. We anticipate that RPL will complement the current repertoire of computational and experimental approaches in enabling the high-throughput determination of secondary and tertiary RNA structures.

  16. Differently Structured Advance Organizers Lead to Different Initial Schemata and Learning Outcomes

    Science.gov (United States)

    Gurlitt, Johannes; Dummel, Sebastian; Schuster, Silvia; Nuckles, Matthias

    2012-01-01

    Does the specific structure of advance organizers influence learning outcomes? In the first experiment, 48 psychology students were randomly assigned to three differently structured advance organizers: a well-structured, a well-structured and key-concept emphasizing, and a less structured advance organizer. These were followed by a sorting task, a…

  17. Orientation determination of interfacial beta-sheet structures in situ.

    Science.gov (United States)

    Nguyen, Khoi Tan; King, John Thomas; Chen, Zhan

    2010-07-01

    Structural information such as orientations of interfacial proteins and peptides is important for understanding properties and functions of such biological molecules, which play crucial roles in biological applications and processes such as antimicrobial selectivity, membrane protein activity, biocompatibility, and biosensing performance. The alpha-helical and beta-sheet structures are the most widely encountered secondary structures in peptides and proteins. In this paper, for the first time, a method to quantify the orientation of the interfacial beta-sheet structure using a combined attenuated total reflectance Fourier transformation infrared spectroscopic (ATR-FTIR) and sum frequency generation (SFG) vibrational spectroscopic study was developed. As an illustration of the methodology, the orientation of tachyplesin I, a 17 amino acid peptide with an antiparallel beta-sheet, adsorbed to polymer surfaces as well as associated with a lipid bilayer was determined using the regular and chiral SFG spectra, together with polarized ATR-FTIR amide I signals. Both the tilt angle (theta) and the twist angle (psi) of the beta-sheet at interfaces are determined. The developed method in this paper can be used to obtain in situ structural information of beta-sheet components in complex molecules. The combination of this method and the existing methodology that is currently used to investigate alpha-helical structures will greatly broaden the application of optical spectroscopy in physical chemistry, biochemistry, biophysics, and structural biology.

  18. Strategic Defense Initiative Organization adaptive structures program overview

    Science.gov (United States)

    Obal, Michael; Sater, Janet M.

    In the currently envisioned architecture none of the Strategic Defense System (SDS) elements to be deployed will receive scheduled maintenance. Assessments of performance capability due to changes caused by the uncertain effects of environments will be difficult, at best. In addition, the system will have limited ability to adjust in order to maintain its required performance levels. The Materials and Structures Office of the Strategic Defense Initiative Organization (SDIO) has begun to address solutions to these potential difficulties via an adaptive structures technology program that combines health and environment monitoring with static and dynamic structural control. Conceivable system benefits include improved target tracking and hit-to-kill performance, on-orbit system health monitoring and reporting, and threat attack warning and assessment.

  19. Institutionalising Human Governance Determinant: Steering Organizations towards Sustainability

    Science.gov (United States)

    Muhamad Hanapiyah, Zulkefli; Daud, Salina; Abdullah, Wan Mohammad Taufik Wan

    2016-03-01

    This paper discusses past researches on human governance elements. Eight elements of human governance are proposed in this paper: leadership, integrity, religiosity, spirituality, culture, recruitment, training and internal control policy. Empirical study shall be conducted in the future study to confirm the eight elements of human governance proposed in this paper. It is expected that these elements may enhance the human governance practice in the organizations.

  20. The accepted laboratory procedure for determining the organic ...

    African Journals Online (AJOL)

    blagoje

    Determining the optimum temperature for dry extrusion of ... based on the principle that a protein source is fed at different sub-requirement levels so that a linear .... This study was funded by the Protein Research Foundation of South Africa.

  1. Determinants influencing consumer behaviour in organic food market

    Directory of Open Access Journals (Sweden)

    Monika Frýdlová

    2011-01-01

    Full Text Available This is a treatise of consumer behaviour in the Czech foods market, respectively, organic food market. This concerns comprehensive analysis of consumer behaviour, which places great emphasis on the motivating factors and barriers, which substantially influence the individual consumers when deciding between conventional foods and organic foods and are operationally broken down into a set of empirical indicators. The database comes from a questionnaire survey to ascertain the trends in the development of the consumption of conventional foods and organic foods including the shopping behaviour of the individual consumers. The results of the questionnaire survey were evaluated by analysis of the qualitative features and other sophisticated statistical methods were also used. Based on the results obtained, the influence of the individual factors on the decision-making behaviour of the consumers when purchasing foods. The main factors that influence consumer behaviour were considered to be the income of the consumers, price of the foods, attitudes that influence the purchase of foods.

  2. Direct electron crystallographic determination of zeolite zonal structures

    International Nuclear Information System (INIS)

    Dorset, Douglas L.; Gilmore, Christopher J.; Jorda, Jose Luis; Nicolopoulos, Stavros

    2007-01-01

    The prospect for improving the success of ab initio zeolite structure investigations with electron diffraction data is evaluated. First of all, the quality of intensities obtained by precession electron diffraction at small hollow cone illumination angles is evaluated for seven representative materials: ITQ-1, ITQ-7, ITQ-29, ZSM-5, ZSM-10, mordenite, and MCM-68. It is clear that, for most examples, an appreciable fraction of a secondary scattering perturbation is removed by precession at small angles. In one case, ZSM-10, it can also be argued that precession diffraction produces a dramatically improved 'kinematical' data set. There seems to no real support for application of a Lorentz correction to these data and there is no reason to expect for any of these samples that a two-beam dynamical scattering relationship between structure factor amplitude and observed intensity should be valid. Removal of secondary scattering by the precession mode appears to facilitate ab initio structure analysis. Most zeolite structures investigated could be solved by maximum entropy and likelihood phasing via error-correcting codes when precession data were used. Examples include the projected structure of mordenite that could not be determined from selected area data alone. One anomaly is the case of ZSM-5, where the best structure determination in projection is made from selected area diffraction data. In a control study, the zonal structure of SSZ-48 could be determined from selected area diffraction data by either maximum entropy and likelihood or traditional direct methods. While the maximum entropy and likelihood approach enjoys some advantages over traditional direct methods (non-dependence on predicted phase invariant sums), some effort must be made to improve the figures of merit used to identify potential structure solutions

  3. Document boundary determination using structural and lexical analysis

    Science.gov (United States)

    Taghva, Kazem; Cartright, Marc-Allen

    2009-01-01

    The document boundary determination problem is the process of identifying individual documents in a stack of papers. In this paper, we report on a classification system for automation of this process. The system employs features based on document structure and lexical content. We also report on experimental results to support the effectiveness of this system.

  4. New method to determine structures in thermonuclear plasmas

    International Nuclear Information System (INIS)

    Tanzi, C.P.

    1998-01-01

    The information from tomographic methods is not always sufficient to determine fast changing structures, e.g. very hot plasmas. A new method has been developed by means of which, among other things, physical mechanisms of plasma instability can be disentangled. 4 refs

  5. Dynamic Capital Structure: Dynamics, Determinants and Speed of Adjustment

    NARCIS (Netherlands)

    Tamirat, A.S.; Trujillo Barrera, A.A.; Pennings, J.M.E.

    2017-01-01

    The corporate finance literature has focused on explaining the determinants of firms target capital structure and speed of adjustment using the well-established theories such as pecking order, signaling and trade-off theories. However, less attention has been paid to understanding the financing

  6. Farm Target Capital Structure: Dynamics, Determinants and Speed of Adjustment

    NARCIS (Netherlands)

    Tamirat, A.S.; Trujillo Barrera, A.A.; Pennings, J.M.E.

    2017-01-01

    The corporate finance literature has focused on explaining the determinants of firms target capital structure and speed of adjustment using the well-established theories such as pecking order, signaling and trade-off theories. However, less attention has been paid to understanding the financing

  7. A Laboratory Exercise in the Determination of Carbohydrate Structures.

    Science.gov (United States)

    White, Bernard J.; Robyt, John F.

    1988-01-01

    Describes an experiment in which students are given a naturally occurring oligosaccharide as an unknown and are asked to determine both its monosaccharide composition and its structure. Discusses methods and experimental techniques including thin layer chromatography and the use of enzymes. (CW)

  8. Determining modulus of elasticity of ancient structural timber

    Science.gov (United States)

    Houjiang Zhang; Lei Zhu; Yanliang Sun; Xiping Wang; Haicheng Yan

    2011-01-01

    During maintenance of ancient timber architectures, it is important to determine mechanical properties of the wood component materials non-destructively and effectively, so that degraded members may be replaced or repaired to avoid structural failure. Experimental materials are four larch (Larix principis-rupprechtii Mayr.) components, which were taken down from the...

  9. Birthday Cake Activity Structured Arrangement for Helping Children Determining Quantities

    Science.gov (United States)

    Mariana, Neni

    2010-01-01

    Few researches have been concerned about relation between children's spatial thinking and number sense. Narrowing for this small research, we focused on one component of spatial thinking, that is structuring objects, and one component of number senses, that is cardinality by determining quantities. This study focused on a design research that was…

  10. Human- and computer-accessible 2D correlation data for a more reliable structure determination of organic compounds. Future roles of researchers, software developers, spectrometer managers, journal editors, reviewers, publisher and database managers toward artificial-intelligence analysis of NMR spectra.

    Science.gov (United States)

    Jeannerat, Damien

    2017-01-01

    The introduction of a universal data format to report the correlation data of 2D NMR spectra such as COSY, HSQC and HMBC spectra will have a large impact on the reliability of structure determination of small organic molecules. These lists of assigned cross peaks will bridge signals found in NMR 1D and 2D spectra and the assigned chemical structure. The record could be very compact, human and computer readable so that it can be included in the supplementary material of publications and easily transferred into databases of scientific literature and chemical compounds. The records will allow authors, reviewers and future users to test the consistency and, in favorable situations, the uniqueness of the assignment of the correlation data to the associated chemical structures. Ideally, the data format of the correlation data should include direct links to the NMR spectra to make it possible to validate their reliability and allow direct comparison of spectra. In order to take the full benefits of their potential, the correlation data and the NMR spectra should therefore follow any manuscript in the review process and be stored in open-access database after publication. Keeping all NMR spectra, correlation data and assigned structures together at all time will allow the future development of validation tools increasing the reliability of past and future NMR data. This will facilitate the development of artificial intelligence analysis of NMR spectra by providing a source of data than can be used efficiently because they have been validated or can be validated by future users. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  11. From bacterial to human dihydrouridine synthase: automated structure determination

    Energy Technology Data Exchange (ETDEWEB)

    Whelan, Fiona, E-mail: fiona.whelan@york.ac.uk; Jenkins, Huw T., E-mail: fiona.whelan@york.ac.uk [The University of York, Heslington, York YO10 5DD (United Kingdom); Griffiths, Samuel C. [University of Oxford, Headington, Oxford OX3 7BN (United Kingdom); Byrne, Robert T. [Ludwig-Maximilians-University Munich, Feodor-Lynen-Strasse 25, 81377 Munich (Germany); Dodson, Eleanor J.; Antson, Alfred A., E-mail: fiona.whelan@york.ac.uk [The University of York, Heslington, York YO10 5DD (United Kingdom)

    2015-06-30

    The crystal structure of a human dihydrouridine synthase, an enzyme associated with lung cancer, with 18% sequence identity to a T. maritima enzyme, has been determined at 1.9 Å resolution by molecular replacement after extensive molecular remodelling of the template. The reduction of uridine to dihydrouridine at specific positions in tRNA is catalysed by dihydrouridine synthase (Dus) enzymes. Increased expression of human dihydrouridine synthase 2 (hDus2) has been linked to pulmonary carcinogenesis, while its knockdown decreased cancer cell line viability, suggesting that it may serve as a valuable target for therapeutic intervention. Here, the X-ray crystal structure of a construct of hDus2 encompassing the catalytic and tRNA-recognition domains (residues 1–340) determined at 1.9 Å resolution is presented. It is shown that the structure can be determined automatically by phenix.mr-rosetta starting from a bacterial Dus enzyme with only 18% sequence identity and a significantly divergent structure. The overall fold of the human Dus2 is similar to that of bacterial enzymes, but has a larger recognition domain and a unique three-stranded antiparallel β-sheet insertion into the catalytic domain that packs next to the recognition domain, contributing to domain–domain interactions. The structure may inform the development of novel therapeutic approaches in the fight against lung cancer.

  12. From bacterial to human dihydrouridine synthase: automated structure determination

    International Nuclear Information System (INIS)

    Whelan, Fiona; Jenkins, Huw T.; Griffiths, Samuel C.; Byrne, Robert T.; Dodson, Eleanor J.; Antson, Alfred A.

    2015-01-01

    The crystal structure of a human dihydrouridine synthase, an enzyme associated with lung cancer, with 18% sequence identity to a T. maritima enzyme, has been determined at 1.9 Å resolution by molecular replacement after extensive molecular remodelling of the template. The reduction of uridine to dihydrouridine at specific positions in tRNA is catalysed by dihydrouridine synthase (Dus) enzymes. Increased expression of human dihydrouridine synthase 2 (hDus2) has been linked to pulmonary carcinogenesis, while its knockdown decreased cancer cell line viability, suggesting that it may serve as a valuable target for therapeutic intervention. Here, the X-ray crystal structure of a construct of hDus2 encompassing the catalytic and tRNA-recognition domains (residues 1–340) determined at 1.9 Å resolution is presented. It is shown that the structure can be determined automatically by phenix.mr-rosetta starting from a bacterial Dus enzyme with only 18% sequence identity and a significantly divergent structure. The overall fold of the human Dus2 is similar to that of bacterial enzymes, but has a larger recognition domain and a unique three-stranded antiparallel β-sheet insertion into the catalytic domain that packs next to the recognition domain, contributing to domain–domain interactions. The structure may inform the development of novel therapeutic approaches in the fight against lung cancer

  13. Using photoelectron diffraction to determine complex molecular adsorption structures

    International Nuclear Information System (INIS)

    Woodruff, D P

    2010-01-01

    Backscattering photoelectron diffraction, particularly in the energy-scan mode, is now an established technique for determining in a quantitative fashion the local structure of adsorbates on surfaces, and has been used successfully for ∼100 adsorbate phases. The elemental and chemical-state specificity afforded by the characteristic core level photoelectron binding energies means that it has particular advantages for molecular adsorbates, as the local geometry of inequivalent atoms in the molecule can be determined in a largely independent fashion. On the other hand, polyatomic molecules present a general problem for all methods of surface structure determination in that a mismatch of intramolecular distances with interatomic distances on the substrate surface means that the atoms in the adsorbed molecule are generally in low-symmetry sites. The quantities measured experimentally then represent an incoherent sum of the properties of each structural domain that is inequivalent with respect to the substrate point group symmetry. This typically leads to greater ambiguity or precision in the structural solutions. The basic principles of the method are described and illustrated with a simple example involving molecule/substrate bonding through only one constituent atom (TiO 2 -(110)/H 2 O). This example demonstrates the importance of obtaining quantitative local structural information. Further examples illustrate both the successes and the problems of this approach when applied to somewhat more complex molecular adsorbates.

  14. Organic matter and soil structure in the Everglades Agricultural Area

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Alan L. [Univ. of Florida, Gainesville, FL (United States); Hanlon, Edward A. [Univ. of Florida, Gainesville, FL (United States)

    2013-01-01

    This publication pertains to management of organic soils (Histosols) in the Everglades Agricultural Area (EAA). These former wetland soils are a major resource for efficient agricultural production and are important globally for their high organic matter content. Recognition of global warming has led to considerable interest in soils as a repository for carbon. Soils rich in organic matter essentially sequester or retain carbon in the profile and can contribute directly to keeping that sequestered carbon from entering the atmosphere. Identification and utilization of management practices that minimize the loss of carbon from organic soils to the atmosphere can minimize effects on global warming and increase the longevity of subsiding Histosols for agricultural use. Understanding and predicting how these muck soils will respond to current and changing land uses will help to manage soil carbon. The objectives of this document are to: a. Discuss organic soil oxidation relative to storing or releasing carbon and nitrogen b. Evaluate effects of cultivation (compare structure for sugarcane vs. uncultivated soil) Based upon the findings from the land-use comparison (sugarcane or uncultivated), organic carbon was higher with cultivation in the lower depths. There is considerable potential for minimum tillage and residue management to further enhance carbon sequestration in the sugarcane system. Carbon sequestration is improved and soil subsidence is slowed with sugarcane production, and both of these are positive outcomes. Taking action to increase or maintain carbon sequestration appears to be appropriate but may introduce some risk to farming operations. Additional management methods are needed to reduce this risk. For both the longevity of these organic soils and from a global perspective, slowing subsidence through BMP implementation makes sense. Since these BMPs also have considerable societal benefit, it remains to be seen if society will help to offset a part or all

  15. Direct experimental determination of the atomic structure at internal interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Browning, N.D. [Oak Ridge National Lab., TN (United States)]|[Illinois Univ., Chicago, IL (United States); Pennycook, S.J. [Oak Ridge National Lab., TN (United States)

    1995-07-01

    A crucial first step in understanding the effect that internal interfaces have on the properties of materials is the ability to determine the atomic structure at the interface. As interfaces can contain atomic disorder, dislocations, segregated impurities and interphases, sensitivity to all of these features is essential for complete experimental characterization. By combining Z-contrast imaging and electron energy loss spectroscopy (EELS) in a dedicated scanning transmission electron microscope (STEM), the ability to probe the structure, bonding and composition at interfaces with the necessary atomic resolution has been obtained. Experimental conditions can be controlled to provide, simultaneously, both incoherent imaging and spectroscopy. This enables interface structures observed in the image to be interpreted intuitively and the bonding in a specified atomic column to be probed directly by EELS. The bonding and structure information can then be correlated using bond-valence sum analysis to produce structural models. This technique is demonstrated for 25{degrees}, 36{degrees} and 67{degrees} symmetric and 45{degrees} and 25{degrees} asymmetric [001] tilt grain boundaries in SrTiO{sub 3} The structures of both types of boundary were found to contain partially occupied columns in the boundary plane. From these experimental results, a series of structural units were identified which could be combined, using continuity of gain boundary structure principles, to construct all [001] tilt boundaries in SrTiO{sub 3}. Using these models, the ability of this technique to address the issues of vacancies and dopant segregation at grain boundaries in electroceramics is discussed.

  16. Global search in photoelectron diffraction structure determination using genetic algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Viana, M L [Departamento de Fisica, Icex, UFMG, Belo Horizonte, Minas Gerais (Brazil); Muino, R Diez [Donostia International Physics Center DIPC, Paseo Manuel de Lardizabal 4, 20018 San Sebastian (Spain); Soares, E A [Departamento de Fisica, Icex, UFMG, Belo Horizonte, Minas Gerais (Brazil); Hove, M A Van [Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China); Carvalho, V E de [Departamento de Fisica, Icex, UFMG, Belo Horizonte, Minas Gerais (Brazil)

    2007-11-07

    Photoelectron diffraction (PED) is an experimental technique widely used to perform structural determinations of solid surfaces. Similarly to low-energy electron diffraction (LEED), structural determination by PED requires a fitting procedure between the experimental intensities and theoretical results obtained through simulations. Multiple scattering has been shown to be an effective approach for making such simulations. The quality of the fit can be quantified through the so-called R-factor. Therefore, the fitting procedure is, indeed, an R-factor minimization problem. However, the topography of the R-factor as a function of the structural and non-structural surface parameters to be determined is complex, and the task of finding the global minimum becomes tough, particularly for complex structures in which many parameters have to be adjusted. In this work we investigate the applicability of the genetic algorithm (GA) global optimization method to this problem. The GA is based on the evolution of species, and makes use of concepts such as crossover, elitism and mutation to perform the search. We show results of its application in the structural determination of three different systems: the Cu(111) surface through the use of energy-scanned experimental curves; the Ag(110)-c(2 x 2)-Sb system, in which a theory-theory fit was performed; and the Ag(111) surface for which angle-scanned experimental curves were used. We conclude that the GA is a highly efficient method to search for global minima in the optimization of the parameters that best fit the experimental photoelectron diffraction intensities to the theoretical ones.

  17. CAPITAL STRUCTURE DETERMINANTS: EVIDENCE FROM PALESTINE AND EGYPT STOCK EXCHANGES

    Directory of Open Access Journals (Sweden)

    Abdul Razak Abdul Hadi

    2017-04-01

    Full Text Available Abstract -This study is driven by the motivation to examine the capital structure determinants for Palestine Stock Exchange (PEX and Egypt Stock Exchange (EGX. Within the framework of capital structure theories, this study uses Generalized Method of Moments (GMM,1982 as an estimation model employing quarterly panel data analysis during the observed period from 2008 till 2012. The test results from GMM indicate that all the examined determinants have significant relationship with leverage. It has a negative value with liquidity, non-debt tax shield, profitability, size and growth. The Egyptian firms have some uniqueness in its trend. Current assets, debt ratio and liquidity behave positively with leverage except for growth. The other tested determinants in Egyptian companies are found to be not significant.

  18. Assembly, Structure, and Functionality of Metal-Organic Networks and Organic Semiconductor Layers at Surfaces

    Science.gov (United States)

    Tempas, Christopher D.

    Self-assembled nanostructures at surfaces show promise for the development of next generation technologies including organic electronic devices and heterogeneous catalysis. In many cases, the functionality of these nanostructures is not well understood. This thesis presents strategies for the structural design of new on-surface metal-organic networks and probes their chemical reactivity. It is shown that creating uniform metal sites greatly increases selectivity when compared to ligand-free metal islands. When O2 reacts with single-site vanadium centers, in redox-active self-assembled coordination networks on the Au(100) surface, it forms one product. When O2 reacts with vanadium metal islands on the same surface, multiple products are formed. Other metal-organic networks described in this thesis include a mixed valence network containing Pt0 and PtII and a network where two Fe centers reside in close proximity. This structure is stable to temperatures >450 °C. These new on-surface assemblies may offer the ability to perform reactions of increasing complexity as future heterogeneous catalysts. The functionalization of organic semiconductor molecules is also shown. When a few molecular layers are grown on the surface, it is seen that the addition of functional groups changes both the film's structure and charge transport properties. This is due to changes in both first layer packing structure and the pi-electron distribution in the functionalized molecules compared to the original molecule. The systems described in this thesis were studied using high-resolution scanning tunneling microscopy, non-contact atomic force microscopy, and X-ray photoelectron spectroscopy. Overall, this work provides strategies for the creation of new, well-defined on-surface nanostructures and adds additional chemical insight into their properties.

  19. Molecular orientation and electronic structure at organic heterojunction interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Shu [Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 Singapore (Singapore); Zhong, Jian Qiang; Wee, Andrew T.S. [Department of Physics, National University of Singapore, 2 Science Drive 3, 117542 Singapore (Singapore); Chen, Wei, E-mail: phycw@nus.edu.sg [Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 Singapore (Singapore); Department of Physics, National University of Singapore, 2 Science Drive 3, 117542 Singapore (Singapore); National University of Singapore (Suzhou) Research Institute, Suzhou (China)

    2015-10-01

    Highlights: • Molecular orientation at the organic heterojunction interfaces. • Energy level alignments at the organic heterojunction interfaces. • Gap-states mediated interfacial energy level alignment. - Abstract: Due to the highly anisotropic nature of π-conjugated molecules, the molecular orientation in organic thin films can significantly affect light absorption, charge transport, energy level alignment (ELA) and hence device performance. Synchrotron-based near-edge X-ray absorption fine structure (NEXAFS) spectroscopy represents a powerful technique for probing molecular orientation. The aim of this review paper is to provide a balanced assessment on the investigation of molecular orientation at the organic–organic heterojunction (OOH) interface by NEXAFS, as well as the gap-states mediated orientation dependent energy level alignment at OOH interfaces. We highlight recent progress in elucidating molecular orientation at OOH interfaces dominated by various interfacial interactions, gap-states controlled orientation dependent energy level alignments at OOH interfaces, and the manipulations of molecular orientation and ELA in OOH.

  20. Organic superalkalis with closed-shell structure and aromaticity

    Science.gov (United States)

    Srivastava, Ambrish Kumar

    2018-06-01

    Benzene (C6H6) and polycyclic hydrocarbons such as naphthalene (C10H8), anthracene (C14H10) and coronene (C24H12) are well known aromatic organic compounds. We study the substitution of Li replacing all H-atoms in these hydrocarbons using density functional method. The vertical ionisation energy of such lithiated species, i.e. C6Li6, C10Li8, C14Li10 and C24Li12 ranges 4.24-4.50 eV, which is lower than the ionisation energy (IE) of Li atom. Thus, these species may behave as superalkalis due to their lower IE than alkali metal. However, these lithiated species possess planar and closed-shell structure, unlike typical superalkalis. Furthermore, all Li-substituted species are aromatic although their degree of aromaticity is reduced as compared to corresponding hydrocarbon analogues. We have further explored the structure of C6Li6 as star-like, unlike its inorganic analogue B3N3Li6, which appears as fan-like structure. We have also demonstrated that the interaction of C6Li6 with a superhalogen (such as BF4) is similar to that of a typical superalkali (such as OLi3). This may further suggest that the proposed lithiated species may form a new class of closed-shell organic superalkalis with aromaticity.

  1. Organic nitrogen rearranges both structure and activity of the soil-borne microbial seedbank.

    Science.gov (United States)

    Leite, Márcio F A; Pan, Yao; Bloem, Jaap; Berge, Hein Ten; Kuramae, Eiko E

    2017-02-15

    Use of organic amendments is a valuable strategy for crop production. However, it remains unclear how organic amendments shape both soil microbial community structure and activity, and how these changes impact nutrient mineralization rates. We evaluated the effect of various organic amendments, which range in Carbon/Nitrogen (C/N) ratio and degradability, on the soil microbiome in a mesocosm study at 32, 69 and 132 days. Soil samples were collected to determine community structure (assessed by 16S and 18S rRNA gene sequences), microbial biomass (fungi and bacteria), microbial activity (leucine incorporation and active hyphal length), and carbon and nitrogen mineralization rates. We considered the microbial soil DNA as the microbial seedbank. High C/N ratio favored fungal presence, while low C/N favored dominance of bacterial populations. Our results suggest that organic amendments shape the soil microbial community structure through a feedback mechanism by which microbial activity responds to changing organic inputs and rearranges composition of the microbial seedbank. We hypothesize that the microbial seedbank composition responds to changing organic inputs according to the resistance and resilience of individual species, while changes in microbial activity may result in increases or decreases in availability of various soil nutrients that affect plant nutrient uptake.

  2. Systematic investigation of the effects of organic film structure on light emitting diode performance

    Science.gov (United States)

    Joswick, M. D.; Campbell, I. H.; Barashkov, N. N.; Ferraris, J. P.

    1996-09-01

    We present a systematic investigation of the effects of organic film structure on light emitting diode (LED) performance. Metal/organic film/metal LEDs were fabricated using a five ring, poly(phenylene vinylene) related oligomer as the active layer. The structure of the vacuum evaporated oligomer films was varied from amorphous to polycrystalline by changing the substrate temperature during deposition. The intrinsic properties of the oligomer films and the LED performance were measured. The measured intrinsic film properties include: optical absorption, photoluminescence (PL) spectra, PL lifetime, PL efficiency, and effective carrier mobility. The measured device characteristics include current-voltage, capacitance-voltage, electroluminescence (EL) efficiency, and the contact metal/organic film Schottky barrier heights. The optical absorption and PL properties of the films are weakly dependent on film structure but the effective carrier mobility decreases with increasing crystallinity. The EL quantum efficiency decreases by more than one order of magnitude, the drive voltage at a fixed current increases, and the electron Schottky barrier height increases as the crystallinity of the film is increased. The diode current-voltage characteristic is determined by the dominant hole current and the electroluminescence efficiency is controlled by the contact limited electron injection. These results demonstrate significant effects of organic film structure on the performance of organic LEDs.

  3. Systematic investigation of the effects of organic film structure on light emitting diode performance

    Energy Technology Data Exchange (ETDEWEB)

    Joswick, M.D.; Campbell, I.H. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Barashkov, N.N.; Ferraris, J.P. [The University of Texas at Dallas, Richardson, Texas 75080 (United States)

    1996-09-01

    We present a systematic investigation of the effects of organic film structure on light emitting diode (LED) performance. Metal/organic film/metal LEDs were fabricated using a five ring, poly(phenylene vinylene) related oligomer as the active layer. The structure of the vacuum evaporated oligomer films was varied from amorphous to polycrystalline by changing the substrate temperature during deposition. The intrinsic properties of the oligomer films and the LED performance were measured. The measured intrinsic film properties include: optical absorption, photoluminescence (PL) spectra, PL lifetime, PL efficiency, and effective carrier mobility. The measured device characteristics include current{endash}voltage, capacitance{endash}voltage, electroluminescence (EL) efficiency, and the contact metal/organic film Schottky barrier heights. The optical absorption and PL properties of the films are weakly dependent on film structure but the effective carrier mobility decreases with increasing crystallinity. The EL quantum efficiency decreases by more than one order of magnitude, the drive voltage at a fixed current increases, and the electron Schottky barrier height increases as the crystallinity of the film is increased. The diode current{endash}voltage characteristic is determined by the dominant hole current and the electroluminescence efficiency is controlled by the contact limited electron injection. These results demonstrate significant effects of organic film structure on the performance of organic LEDs. {copyright} {ital 1996 American Institute of Physics.}

  4. Experimental investigation of multiple self-organized structures in plasma

    International Nuclear Information System (INIS)

    Ivan, L. M.; Gaman, C.; Aflori, M.; Mihai-Plugaru, M.; Dimitriu, D.G.; Lozneanu, E.; Sanduloviciu, M.

    2005-01-01

    Complex space charge configuration emerges by self-organization in front of an electrode immersed in plasma when its potential is increased at a certain critical value. Consisting from a nucleus protected from the surrounding plasma by an electrical double layer, the complexity reveals an internal structure and behaviour which remind us primitive organisms. Thus the complexity is not static but stationary open system in which continuous decay is constantly compensated by substance and energy from the surrounding plasma. Endowed with a special kind of memory the complexity can work as an intelligent multifunctional system and consequently it is also able to perform innovations after selective interaction with an environment in evolution. Additionally, the complexity is able to replicate by division. (authors)

  5. Social Capital in Organizations - Beyond Structure and Metaphor

    DEFF Research Database (Denmark)

    Waldstrøm, Christian

    2003-01-01

    a consistent, bridging theory. Finally, there is a lack of understanding on how social capital develops over time and the potential benefits of taking a life-cycle view of social capital. In conclusion, the field of social capital in organizations still needs a consistent and coordinated research effort......The importance and usefulness of social capital as a concept in the study of organizations have been established by a large body of research. The aim of this paper is to review the concept of social capital in an organizational context, and it identifies five main issues that need to be addressed...... in future research before social capital can move definitively beyond being merely a metaphor for advantage. First, the unresolved issue of causality is a barrier in the study of social structure and social capital alike, and hampers both measuring scales and implications drawn from empirical research...

  6. Single-Walled Carbon-Nanotubes-Based Organic Memory Structures

    Directory of Open Access Journals (Sweden)

    Sundes Fakher

    2016-09-01

    Full Text Available The electrical behaviour of organic memory structures, based on single-walled carbon-nanotubes (SWCNTs, metal–insulator–semiconductor (MIS and thin film transistor (TFT structures, using poly(methyl methacrylate (PMMA as the gate dielectric, are reported. The drain and source electrodes were fabricated by evaporating 50 nm gold, and the gate electrode was made from 50 nm-evaporated aluminium on a clean glass substrate. Thin films of SWCNTs, embedded within the insulating layer, were used as the floating gate. SWCNTs-based memory devices exhibited clear hysteresis in their electrical characteristics (capacitance–voltage (C–V for MIS structures, as well as output and transfer characteristics for transistors. Both structures were shown to produce reliable and large memory windows by virtue of high capacity and reduced charge leakage. The hysteresis in the output and transfer characteristics, the shifts in the threshold voltage of the transfer characteristics, and the flat-band voltage shift in the MIS structures were attributed to the charging and discharging of the SWCNTs floating gate. Under an appropriate gate bias (1 s pulses, the floating gate is charged and discharged, resulting in significant threshold voltage shifts. Pulses as low as 1 V resulted in clear write and erase states.

  7. Determinants and Management Outcomes of Pelvic Organ Prolapse ...

    African Journals Online (AJOL)

    determine, however, the life time risk of requiring at least one operation to ... are appropriately treated with pelvic floor exercises and/or physical ... improve their quality of life. In Nnewi .... [1,17,19-21] Pregnancy itself, without vaginal birth has.

  8. Ammonia emission from organic pig houses determined with local parameters

    NARCIS (Netherlands)

    Aarnink, A.J.A.; Hol, J.M.G.; Ogink, N.W.M.

    2016-01-01

    The objective of this study was to determine the ammonia emissions from houses for growing-finishing pigs with an outside yard. While regular emission measurements are not possible in these open systems another approach was used. Local parameters were measured and used in an existing NH3 emission

  9. Electrical characterization of organic-on-inorganic semiconductor Schottky structures

    International Nuclear Information System (INIS)

    Guellue, Oe; Tueruet, A; Asubay, S

    2008-01-01

    We prepared a methyl red/p-InP organic-inorganic (OI) Schottky device formed by evaporation of an organic compound solution directly to a p-InP semiconductor wafer. The value of the optical band gap energy of the methyl red organic film on a glass substrate was obtained as 2.0 eV. It was seen that the Al/methyl red/p-InP contacts showed a good rectifying behavior. An ideality factor of 2.02 and a barrier height (Φ b ) of 1.11 eV for the Al/methyl red/p-InP contact were determined from the forward bias I-V characteristics. It was seen that the value of 1.11 eV obtained for Φ b for the Al/methyl red/p-InP contact was significantly larger than the value of 0.83 eV for conventional Al/p-InP Schottky diodes. Modification of the interfacial potential barrier for the Al/p-InP diode was achieved using a thin interlayer of the methyl red organic semiconductor. This ascribed to the fact that the methyl red interlayer increases the effective Φ b by influencing the space charge region of InP

  10. Family Structure as a Correlate of Organized Sport Participation among Youth.

    Science.gov (United States)

    McMillan, Rachel; McIsaac, Michael; Janssen, Ian

    2016-01-01

    Organized sport is one way that youth participate in physical activity. There are disparities in organized sport participation by family-related factors. The purpose of this study was to determine whether non-traditional family structure and physical custody arrangements are associated with organized sport participation in youth, and if so whether this relationship is mediated by socioeconomic status. Data were from the 2009-10 Health Behaviour in School-aged Children survey, a nationally representative cross-section of Canadian youth in grades 6-10 (N = 21,201). Information on family structure was derived from three survey items that asked participants the number of adults they lived with, their relationship to these adults, and if applicable, how often they visited another parent outside their home. Participants were asked whether or not they were currently involved in an organized sport. Logistic regression was used to compare the odds of organized sport participation according to family structure. Bootstrap-based mediation analysis was used to assess mediation by perceived family wealth. The results indicated that by comparison to traditional families, boys and girls from reconstituted families with irregular visitation of a second parent, reconstituted families with regular visitation of a second parent, single-parent families with irregular visitation of a second parent, and single-parent families with regular visitation of a second parent were less likely to participate in organized sport than those from traditional families, with odds ratios ranging from 0.48 (95% confidence interval: 0.38-0.61) to 0.78 (95% confidence interval: 0.56-1.08). The relationship between family structure and organized sport was significantly mediated by perceived family wealth, although the magnitude of the mediation was modest (ie, reconstituted families experienced significant disparities in organized sport participation that was partially mediated by perceived family wealth.

  11. Family Structure as a Correlate of Organized Sport Participation among Youth.

    Directory of Open Access Journals (Sweden)

    Rachel McMillan

    Full Text Available Organized sport is one way that youth participate in physical activity. There are disparities in organized sport participation by family-related factors. The purpose of this study was to determine whether non-traditional family structure and physical custody arrangements are associated with organized sport participation in youth, and if so whether this relationship is mediated by socioeconomic status. Data were from the 2009-10 Health Behaviour in School-aged Children survey, a nationally representative cross-section of Canadian youth in grades 6-10 (N = 21,201. Information on family structure was derived from three survey items that asked participants the number of adults they lived with, their relationship to these adults, and if applicable, how often they visited another parent outside their home. Participants were asked whether or not they were currently involved in an organized sport. Logistic regression was used to compare the odds of organized sport participation according to family structure. Bootstrap-based mediation analysis was used to assess mediation by perceived family wealth. The results indicated that by comparison to traditional families, boys and girls from reconstituted families with irregular visitation of a second parent, reconstituted families with regular visitation of a second parent, single-parent families with irregular visitation of a second parent, and single-parent families with regular visitation of a second parent were less likely to participate in organized sport than those from traditional families, with odds ratios ranging from 0.48 (95% confidence interval: 0.38-0.61 to 0.78 (95% confidence interval: 0.56-1.08. The relationship between family structure and organized sport was significantly mediated by perceived family wealth, although the magnitude of the mediation was modest (ie, <20% change in effect estimate. In conclusion, youth living in both single-parent and reconstituted families experienced significant

  12. X-ray structure determination and deuteration of nattokinase

    International Nuclear Information System (INIS)

    Yanagisawa, Yasuhide; Chatake, Toshiyuki; Naito, Sawa; Ohsugi, Tadanori; Yatagai, Chieko; Sumi, Hiroyuki; Kawaguchi, Akio; Chiba-Kamosida, Kaori; Ogawa, Megumi; Adachi, Tatsumi; Morimoto, Yukio

    2013-01-01

    X-ray structure determination and deuteration of nattokinase were performed to facilitate neutron crystallographic analysis. Nattokinase (NK) is a strong fibrinolytic enzyme, which is produced in abundance by Bacillus subtilis natto. Although NK is a member of the subtilisin family, it displays different substrate specificity when compared with other subtilisins. The results of molecular simulations predict that hydrogen arrangements around Ser221 at the active site probably account for the substrate specificity of NK. Therefore, neutron crystallographic analysis should provide valuable information that reveals the enzymatic mechanism of NK. In this report, the X-ray structure of the non-hydrogen form of undeuterated NK was determined, and the preparation of deuterated NK was successfully achieved. The non-hydrogen NK structure was determined at 1.74 Å resolution. The three-dimensional structures of NK and subtilisin E from Bacillus subtilis DB104 are near identical. Deuteration of NK was carried out by cultivating Bacillus subtilis natto in deuterated medium. The D 2 O resistant strain of Bacillus subtilis natto was obtained by successive cultivation rounds, in which the concentration of D 2 O in the medium was gradually increased. NK was purified from the culture medium and its activity was confirmed by the fibrin plate method. The results lay the framework for neutron protein crystallography analysis

  13. X-ray structure determination and deuteration of nattokinase

    Energy Technology Data Exchange (ETDEWEB)

    Yanagisawa, Yasuhide [Chiba Institute of Science, 15-8 Shiomi-cho, Cho-shi, Chiba 288-025 (Japan); Chatake, Toshiyuki [Kyoto University, Asashironishi 2, Kumatori, Osaka 590-0494 (Japan); Naito, Sawa; Ohsugi, Tadanori; Yatagai, Chieko; Sumi, Hiroyuki [Kurashiki University of Science and the Arts, 2640 Nishinoura, Tsurajima-cho, Kurashiki, Okayama 712-8505 (Japan); Kawaguchi, Akio [Kyoto University, Asashironishi 2, Kumatori, Osaka 590-0494 (Japan); Chiba-Kamosida, Kaori [Nippon Advanced Technology Co. Ltd, J-PARC, 2-4 Shirane Shirakata, Tokai, Ibaraki 319-1195 (Japan); Ogawa, Megumi; Adachi, Tatsumi [Chiba Institute of Science, 15-8 Shiomi-cho, Cho-shi, Chiba 288-025 (Japan); Morimoto, Yukio [Kyoto University, Asashironishi 2, Kumatori, Osaka 590-0494 (Japan)

    2013-11-01

    X-ray structure determination and deuteration of nattokinase were performed to facilitate neutron crystallographic analysis. Nattokinase (NK) is a strong fibrinolytic enzyme, which is produced in abundance by Bacillus subtilis natto. Although NK is a member of the subtilisin family, it displays different substrate specificity when compared with other subtilisins. The results of molecular simulations predict that hydrogen arrangements around Ser221 at the active site probably account for the substrate specificity of NK. Therefore, neutron crystallographic analysis should provide valuable information that reveals the enzymatic mechanism of NK. In this report, the X-ray structure of the non-hydrogen form of undeuterated NK was determined, and the preparation of deuterated NK was successfully achieved. The non-hydrogen NK structure was determined at 1.74 Å resolution. The three-dimensional structures of NK and subtilisin E from Bacillus subtilis DB104 are near identical. Deuteration of NK was carried out by cultivating Bacillus subtilis natto in deuterated medium. The D{sub 2}O resistant strain of Bacillus subtilis natto was obtained by successive cultivation rounds, in which the concentration of D{sub 2}O in the medium was gradually increased. NK was purified from the culture medium and its activity was confirmed by the fibrin plate method. The results lay the framework for neutron protein crystallography analysis.

  14. Overconfidence, Managerial Optimism, and the Determinants of Capital Structure

    Directory of Open Access Journals (Sweden)

    Alexandre di Miceli da Silveira

    2008-12-01

    Full Text Available This research examines the determinants of the capital structure of firms introducing a behavioral perspective that has received little attention in corporate finance literature. The following central hypothesis emerges from a set of recently developed theories: firms managed by optimistic and/or overconfident people will choose more levered financing structures than others, ceteris paribus. We propose different proxies for optimism/overconfidence, based on the manager’s status as an entrepreneur or non-entrepreneur, an idea that is supported by theories and solid empirical evidence, as well as on the pattern of ownership of the firm’s shares by its manager. The study also includes potential determinants of capital structure used in earlier research. We use a sample of Brazilian firms listed in the Sao Paulo Stock Exchange (Bovespa in the years 1998 to 2003. The empirical analysis suggests that the proxies for the referred cognitive biases are important determinants of capital structure. We also found as relevant explanatory variables: profitability, size, dividend payment and tangibility, as well as some indicators that capture the firms’ corporate governance standards. These results suggest that behavioral approaches based on human psychology research can offer relevant contributions to the understanding of corporate decision making.

  15. Modern electronic structure theory and applications in organic chemistry

    CERN Document Server

    Davidson, ER

    1997-01-01

    This volume focuses on the use of quantum theory to understand and explain experiments in organic chemistry. High level ab initio calculations, when properly performed, are useful in making quantitative distinctions between various possible interpretations of structures, reactions and spectra. Chemical reasoning based on simpler quantum models is, however, essential to enumerating the likely possibilities. The simpler models also often suggest the type of wave function likely to be involved in ground and excited states at various points along reaction paths. This preliminary understanding is n

  16. CONVERSION PRODUCT STRUCTURE AS TOOL TO INCREASE YIELD PROCESSING ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    A. I. Khorev

    2014-01-01

    Full Text Available The authors' analysis of the performance of organizations, processing raw materials of agricultural origin, in particular, dealing with meat processing, identified the need to develop tools to increase their profitability. Unlike common approaches to assessing the profitability of the processing organizations, taking into account only the interests of the organization's leadership and buyers of products, the authors proposed and implemented a concept based on the interests of participants in the triune balance business activities: owners of capital, management organizations and consumers. As one of the tools for improving the yield of processing organizations are invited to transform their product mix of economic evaluations of profitability of each product line positions. Russian researchers income from product sales are traditionally measured by indicators such as net income, income from sales, profit margins and profitability level - in terms of return on sales. The disadvantage of using these indicators, according to the authors, is their lack of objectivity in the evaluation of the effectiveness of investment business owners. In this work was used unconventional and non-proliferation in the Russian practice, the rate of economic value added (EVA, a built - in system of profitability assortment positions. As indicators, the production of a particular product line units proposed and used two quantitative indicators - EVA level per unit of production and profitability of production (for EVA, as well as a quality parameter - the level of demand. Developed by the evaluation program transformation product structure represented as a matrix management capabilities, allowing to achieve a balance of interests of the triune main participants in business activity.

  17. Experimental determination of the structure of H3+

    International Nuclear Information System (INIS)

    Gaillard, M.J.; Gemmell, D.S.; Goldring, G.; Levine, I.; Pietsch, W.J.; Poizat, J.C.; Ratkowski, A.J.; Remillieux, J.; Vager, Z.; Zabransky, B.J.

    1978-01-01

    Three different measurements on the structure of the H 3 + molecular ion are reported. The measurements all make use of a new technique: the foil-induced dissociation of a fast molecular-ion beam. It is shown that the structure is equilaterally triangular in shape. The most probable length of side of the triangle is determined by the three measurements to be 0.97 +- 0.03 A, 0.95 +- 0.06 A, and 1.2 +- 0.2 A, respectively

  18. Sulfated oligosaccharide structures, as determined by NMR techniques

    Energy Technology Data Exchange (ETDEWEB)

    Noseda, M.D.; Duarte, M.E.R.; Tischer, C.A.; Gorin, P.A.J. [Parana Univ., Curitiba, PR (Brazil). Dept. De Bioquimica; Cerezo, A.S. [Buenos Aires Univ. Nacional (Argentina). Dept. de Quimica Organica

    1997-12-31

    Carrageenans are sulfated polysaccharides, produced by red seaweeds (Rhodophyta), that have important biological and physico-chemical properties. Using partial autohydrolysis, we obtained sulfated oligosaccharides from a {lambda}-carrageenan (Noseda and Cerezo, 1993). These oligosaccharides are valuable not only for the study of the structures of the parent carrageenans but also for their possible biological activities. In this work we determined the chemical structure of one of the sulfated oligosaccharides using 1D and 2D NMR techniques. (author) 4 refs., 8 figs., 1 tabs.

  19. Taking MAD to the extreme: ultrafast protein structure determination

    International Nuclear Information System (INIS)

    Walsh, M.A.; Dementieva, I.; Evans, G.; Sanishvili, R.; Joachimiak, A.

    1999-01-01

    Multiwavelength anomalous diffraction data were measured in 23 min from a 16 kDa selenomethionyl-substituted protein, producing experimental phases to 2.25 (angstrom) resolution. The data were collected on a mosaic 3 x 3 charge-coupled device using undulator radiation from the Structural Biology Center 19ID beamline at the Argonne National Laboratory's Advanced Photon Source. The phases were independently obtained semiautomatically by two crystallographic program suites, CCP4 and CNS. The quality and speed of this data acquisition exemplify the opportunities at third-generation synchrotron sources for high-throughput protein crystal structure determination

  20. Implantation measurements to determine tritium permeation in first wall structures

    International Nuclear Information System (INIS)

    Holland, D.F.; Causey, R.A.

    1983-01-01

    A principal safety concern for a D-T burning fusion reactor is release of tritium during routine operation. Tritium implantation into first wall structures, and subsequent permeation into coolants, is potentially an important source of tritium loss. This paper reports on an experiment in which an ion accelerator was used to implant deuterium atoms in a stainless steel disk to simulate tritium implantation in first wall structures. The permeation rate was measured under various operating conditions. These results were used in the TMAP computer code to determine potential tritium loss rates for fusion reactors

  1. DETERMINANT FACTORS OF THE CAPITAL STRUCTURE OF BRAZILIAN TECHNOLOGY COMPANIES

    Directory of Open Access Journals (Sweden)

    Camila Freitas Sant´Ana

    2015-12-01

    Full Text Available The purpose of this study is to identify determinant factors of the capital structure of Brazilian technology companies. The research was characterized as descriptive, document and quantitative, consisting of 21 companies in the communications, telecommunications and digital industry, according to the Exame magazine ranking. The analysis was established from 2009 to 2013 using panel data regression. The results indicate that the growth rate of capital and control type have a positive relationship with the general and long-term debt. However, it was found that company size, profitability and type of capital point to a negative relationship with the capital structure.

  2. Resolving anatomical and functional structure in human brain organization: identifying mesoscale organization in weighted network representations.

    Science.gov (United States)

    Lohse, Christian; Bassett, Danielle S; Lim, Kelvin O; Carlson, Jean M

    2014-10-01

    Human brain anatomy and function display a combination of modular and hierarchical organization, suggesting the importance of both cohesive structures and variable resolutions in the facilitation of healthy cognitive processes. However, tools to simultaneously probe these features of brain architecture require further development. We propose and apply a set of methods to extract cohesive structures in network representations of brain connectivity using multi-resolution techniques. We employ a combination of soft thresholding, windowed thresholding, and resolution in community detection, that enable us to identify and isolate structures associated with different weights. One such mesoscale structure is bipartivity, which quantifies the extent to which the brain is divided into two partitions with high connectivity between partitions and low connectivity within partitions. A second, complementary mesoscale structure is modularity, which quantifies the extent to which the brain is divided into multiple communities with strong connectivity within each community and weak connectivity between communities. Our methods lead to multi-resolution curves of these network diagnostics over a range of spatial, geometric, and structural scales. For statistical comparison, we contrast our results with those obtained for several benchmark null models. Our work demonstrates that multi-resolution diagnostic curves capture complex organizational profiles in weighted graphs. We apply these methods to the identification of resolution-specific characteristics of healthy weighted graph architecture and altered connectivity profiles in psychiatric disease.

  3. Analyze Of Interrelation Between Knowledge Management And Organizatıonal Structure Of Organization

    OpenAIRE

    MLÁDKOVÁ, Ludmila

    2011-01-01

    The aim of the article is to discuss interrelation between knowledge management and organizational structure of organization. Organizational structure is a backbone of the organization. Type of organizational structure used has strong impact on everyday life of organization and influences all its activities, including knowledge management. From the point of view of knowledge management, three basic groups of organizational structures can be identified in organizations; top down structures, bo...

  4. Determinants of engagement in mental health consumer-run organizations.

    Science.gov (United States)

    Brown, Louis Davis; Townley, Greg

    2015-04-01

    Mental health consumer-run organizations (CROs) are a low-cost, evidence-based strategy for promoting recovery. To increase CRO utilization, characteristics that promote engagement need to be identified and encouraged. The study examined individual and organizational characteristics that predict three types of engagement in CROs-attendance, leadership involvement, and socially supportive involvement. Surveys were administered to 250 CRO members attending 20 CROs. Leaders of each CRO reported organizational characteristics through a separate questionnaire. Multilevel regression models examined relationships between predictors and indicators of CRO engagement. Perceived sense of community was the only characteristic that predicted attendance, leadership involvement, and socially supportive involvement (p<.001). Perceived organizational empowerment, shared leadership, peer counseling, and several demographic characteristics also predicted some measures of engagement. CROs that can effectively promote sense of community, organizational empowerment, shared leadership, and peer counseling may be better able to engage participants. The discussion considers several strategies to enhance these characteristics, such as collectively establishing values and practicing shared decision making.

  5. Osteoarthritis Severity Determination using Self Organizing Map Based Gabor Kernel

    Science.gov (United States)

    Anifah, L.; Purnomo, M. H.; Mengko, T. L. R.; Purnama, I. K. E.

    2018-02-01

    The number of osteoarthritis patients in Indonesia is enormous, so early action is needed in order for this disease to be handled. The aim of this paper to determine osteoarthritis severity based on x-ray image template based on gabor kernel. This research is divided into 3 stages, the first step is image processing that is using gabor kernel. The second stage is the learning stage, and the third stage is the testing phase. The image processing stage is by normalizing the image dimension to be template to 50 □ 200 image. Learning stage is done with parameters initial learning rate of 0.5 and the total number of iterations of 1000. The testing stage is performed using the weights generated at the learning stage. The testing phase has been done and the results were obtained. The result shows KL-Grade 0 has an accuracy of 36.21%, accuracy for KL-Grade 2 is 40,52%, while accuracy for KL-Grade 2 and KL-Grade 3 are 15,52%, and 25,86%. The implication of this research is expected that this research as decision support system for medical practitioners in determining KL-Grade on X-ray images of knee osteoarthritis.

  6. Volume determination of organs using NMR-CT images

    International Nuclear Information System (INIS)

    Matsumoto, Kunihiko; Hyodo, Kazuyuki; Ikehira, Hiroo; Fukuda, Nobuo; Tateno, Yukio.

    1986-01-01

    Water phantoms with the volume of 10, 50, 100, 200 and 300 ml surrounded by salad oil were made. The basic experiments were achieved with these phantoms to investigate the accuracy of volume determination and the influence of RF pulse series. NMR - CT employed was Asahi Mark - J. The magnetic field was 0.1T (conductive magnet). The slice thickness were 15 mm. The contour of the phantoms was determined manually using truck - ball and/or automatically by a computer program developed by us. The volume was calculated by the summation of contour area multiplied by the slice pitch. At volumes < 50 ml the error is quite significant but at larger volumes greater than 300 ml the error is reduced to ± 10 %. The volumes of the liver and spleen were measured using both coronal and transverse scans. The error in volume measurement between the scans taken in different planes was found to be 7.0 ± 4.1 % for the liver and 12.4 ± 4.65 % for the spleen. (author)

  7. The levels of fruit organization in Celastraceae and structural diversity of pirenariums in Cassinoideae

    OpenAIRE

    Ivan A. Savinov

    2012-01-01

    The levels of fruit organization are determined for the Celastraceae family on the basis of fruit morphology and anatomical study of pericarp (114 species from 45 genera. Analysis of their correlation with basal and derivative lineages according to the last molecular data is conducted and reconstruction of initial stages of the family phylogeny is presented. Special focus to structural diversity of pirenarium in Cassinoideae subfamily is spared.

  8. Inorganic Biominerals in Crustaceans are Structurally Independent of Organic Framework

    Science.gov (United States)

    Mergelsberg, S. T.; Michel, F. M.; Mukhopadhyay, B.; Dove, P. M.

    2015-12-01

    Biomineralization of calcium carbonate (CaCO3) as crystalline calcite or amorphous CaCO3 (ACC) occurs in the exoskeletons of all crustaceans. These cuticles are complex composites of inorganic mineral and organic macromolecules with highly divergent morphologies that are adapted to the extreme variations in environmental pressures within their diverse ecological niches. The remarkable variations and adaptations that form, infer a highly efficient and regulated mechanism for biomineralization that is most likely orchestrated by a myriad of biomacromolecules (Ziegler A 2012). The roles of these peptides and organic metabolites during CaCO3 biomineralization are not well understood. In part, this is due to a lack of knowledge of crustacean homeostasis. In a step toward understanding cuticle mineralization in crustaceans, this study asks: Which molecules affect biomineralization? Do the biomineral-active molecules vary greatly between species and body parts? Recent studies of polysaccharide controls on mineralization also raise the question of whether small heterogeneities in chitin, the most abundant biopolymer of the composite, could be primarily responsible for differences in CaCO3 crystallinity. This study used a novel spectroscopic approach to characterize the mineral and organic components of exoskeletons from three Malacostraca organisms — American Lobster (Homarus americanus), Dungeness Crab (Metacarcinus magister), and Red Rock Crab (Cancer productus). Using high-energy x-ray diffraction and Raman spectroscopy, the cuticles of three major body parts from these organisms were analyzed for the structure and bulk chemistry of its chitin and CaCO3 components. The findings indicate that Raman spectroscopy provides adequate resolution to show that crystallinity of chitin and the CaCO3 mineral component are chemically independent of each other, although their crystallinities co-vary for Brachyura species (Dungeness and Red Rock Crabs). Insights from this study

  9. The potential for biological structure determination with pulsed neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, C.C. [CLRC Rutherford Appleton Laboratory, Chilton Didcot Oxon (United Kingdom)

    1994-12-31

    The potential of pulsed neutron diffraction in structural determination of biological materials is discussed. The problems and potential solutions in this area are outlined, with reference to both current and future sources and instrumentation. The importance of developing instrumentation on pulsed sources in emphasized, with reference to the likelihood of future expansion in this area. The possibilities and limitations of single crystal, fiber and powder diffraction in this area are assessed.

  10. The potential for biological structure determination with pulsed neutrons

    International Nuclear Information System (INIS)

    Wilson, C.C.

    1994-01-01

    The potential of pulsed neutron diffraction in structural determination of biological materials is discussed. The problems and potential solutions in this area are outlined, with reference to both current and future sources and instrumentation. The importance of developing instrumentation on pulsed sources in emphasized, with reference to the likelihood of future expansion in this area. The possibilities and limitations of single crystal, fiber and powder diffraction in this area are assessed

  11. Determining the helicity structure of third generation resonances

    International Nuclear Information System (INIS)

    Papaefstathiou, Andreas

    2011-11-01

    We examine methods that have been proposed for determining the helicity structure of decays of new resonances to third generation quarks and/or leptons. We present analytical and semi-analytical predictions and assess the applicability of the relevant variables in realistic reconstruction scenarios using Monte Carlo-generated events, including the effects of QCD radiation and multiple parton interactions, combinatoric ambiguities and fast detector simulation. (orig.)

  12. Determination of the Basin Structure Beneath European Side of Istanbul

    Science.gov (United States)

    Karabulut, Savas; Cengiz Cinku, Mulla; Thomas, Michael; Lamontagne, Maurice

    2016-04-01

    Istanbul (near North Anatolian Fault Zone:NAFZ, Turkey) is located in northern part of Sea of Marmara, an area that has been influenced by possible Marmara Earthquakes. The general geology of Istanbul divided into two stratigraphic unit such as sedimentary (from Oligocene to Quaternary Deposits) and bedrock (Paleozoic and Eocene). The bedrock units consists of sand stone, clay stone to Paleozoic age and limestone to Eocene age and sedimentary unit consist of sand, clay, mil and gravel from Oligocene to Quaternary age. Earthquake disaster mitigation studies divided into two important phases, too. Firstly, earthquake, soil and engineering structure problems identify for investigation area, later on strategic emergency plan can prepare for these problems. Soil amplification play important role the disaster mitigation and the site effect analysis and basin structure is also a key parameter for determining of site effect. Some geophysical, geological and geotechnical measurements are requeired to defined this relationship. Istanbul Megacity has been waiting possible Marmara Earthquake and their related results. In order to defined to possible damage potential related to site effect, gravity measurements carried out for determining to geological structure, basin geometry and faults in Istanbul. Gravity data were collected at 640 sites by using a Scientrex CG-5 Autogravity meter Standard corrections applied to the gravity data include those for instrumental drift, Earth tides and latitude, and the free-air and Bouguer corrections. The corrected gravity data were imported into a Geosoft database to create a grid and map of the Bouguer gravity anomaly (grid cell size of 200 m). As a previously results, we determined some lineminants, faults and basins beneath Istanbul City. Especially, orientation of faults were NW-SE direction and some basin structures determined on between Buyukcekmece and Kucukcekmece Lake.

  13. Using the Cambridge structure database of organic and organometalic compounds in structure biology

    Czech Academy of Sciences Publication Activity Database

    Hašek, Jindřich

    2010-01-01

    Roč. 17, 1a (2010), b24-b26 ISSN 1211-5894. [Discussions in Structural Molecular Biology /8./. Nové Hrady, 18.03.2010-20.03.2010] R&D Projects: GA AV ČR IAA500500701; GA ČR GA305/07/1073 Institutional research plan: CEZ:AV0Z40500505 Keywords : organic chemistry * Cambridge Structure Data base * molecular structure Subject RIV: CD - Macromolecular Chemistry http://xray.cz/ms/bul2010-1a/friday2.pdf

  14. Evolution and structural organization of the C proteins of paramyxovirinae.

    Directory of Open Access Journals (Sweden)

    Michael K Lo

    Full Text Available The phosphoprotein (P gene of most Paramyxovirinae encodes several proteins in overlapping frames: P and V, which share a common N-terminus (PNT, and C, which overlaps PNT. Overlapping genes are of particular interest because they encode proteins originated de novo, some of which have unknown structural folds, challenging the notion that nature utilizes only a limited, well-mapped area of fold space. The C proteins cluster in three groups, comprising measles, Nipah, and Sendai virus. We predicted that all C proteins have a similar organization: a variable, disordered N-terminus and a conserved, α-helical C-terminus. We confirmed this predicted organization by biophysically characterizing recombinant C proteins from Tupaia paramyxovirus (measles group and human parainfluenza virus 1 (Sendai group. We also found that the C of the measles and Nipah groups have statistically significant sequence similarity, indicating a common origin. Although the C of the Sendai group lack sequence similarity with them, we speculate that they also have a common origin, given their similar genomic location and structural organization. Since C is dispensable for viral replication, unlike PNT, we hypothesize that C may have originated de novo by overprinting PNT in the ancestor of Paramyxovirinae. Intriguingly, in measles virus and Nipah virus, PNT encodes STAT1-binding sites that overlap different regions of the C-terminus of C, indicating they have probably originated independently. This arrangement, in which the same genetic region encodes simultaneously a crucial functional motif (a STAT1-binding site and a highly constrained region (the C-terminus of C, seems paradoxical, since it should severely reduce the ability of the virus to adapt. The fact that it originated twice suggests that it must be balanced by an evolutionary advantage, perhaps from reducing the size of the genetic region vulnerable to mutations.

  15. MOTIVATION INTERNALIZATION AND SIMPLEX STRUCTURE IN SELF-DETERMINATION THEORY.

    Science.gov (United States)

    Ünlü, Ali; Dettweiler, Ulrich

    2015-12-01

    Self-determination theory, as proposed by Deci and Ryan, postulated different types of motivation regulation. As to the introjected and identified regulation of extrinsic motivation, their internalizations were described as "somewhat external" and "somewhat internal" and remained undetermined in the theory. This paper introduces a constrained regression analysis that allows these vaguely expressed motivations to be estimated in an "optimal" manner, in any given empirical context. The approach was even generalized and applied for simplex structure analysis in self-determination theory. The technique was exemplified with an empirical study comparing science teaching in a classical school class versus an expeditionary outdoor program. Based on a sample of 84 German pupils (43 girls, 41 boys, 10 to 12 years old), data were collected using the German version of the Academic Self-Regulation Questionnaire. The science-teaching format was seen to not influence the pupils' internalization of identified regulation. The internalization of introjected regulation differed and shifted more toward the external pole in the outdoor teaching format. The quantification approach supported the simplex structure of self-determination theory, whereas correlations may disconfirm the simplex structure.

  16. Determinants of capital structure: evidence from the Czech automotive industry

    Directory of Open Access Journals (Sweden)

    Pavlína Pinková

    2012-01-01

    Full Text Available The objective of the paper is to identify the determinants influencing the capital structure of large and medium-sized enterprises of the automotive industry in the Czech Republic. The sample consists of 100 companies belonging to NACE division 29. The data come from financial statements of selected companies and cover a period from 2006 to 2010. For the purpose of the paper quantitative research is used. The selection of appropriate dependent and independent is realized on the basis of secondary research on studies of capital structure. The analysis of variance, correlation and regression analyses have been performed to see the nature of relationship between variables. Size, tangibility, profitability and liquidity appear to be relevant determinants of capital structure. Growth is not a statistically significant determinant of leverage. It has been observed that the maturity of debt has to be considered, since the investigation of total debt only does not provide precious results. The findings do not unequivocally support either the static trade-off theory or the pecking order theory.

  17. Local magnetic structure determination using polarized neutron holography

    International Nuclear Information System (INIS)

    Szakál, Alex; Markó, Márton; Cser, László

    2015-01-01

    A unique and important property of the neutron is that it possesses magnetic moment. This property is widely used for determination of magnetic structure of crystalline samples observing the magnetic components of the diffraction peaks. Investigations of diffraction patterns give information only about the averaged structure of a crystal but for discovering of local spin arrangement around a specific (e.g., impurity) nucleus remains still a challenging problem. Neutron holography is a useful tool to investigate the local structure around a specific nucleus embedded in a crystal lattice. The method has been successfully applied experimentally in several cases using non-magnetic short range interaction of the neutron and the nucleus. A mathematical model of the hologram using interaction between magnetic moment of the atom and the neutron spin for polarized neutron holography is provided. Validity of a polarized neutron holographic experiment is demonstrated by applying the proposed method on model systems

  18. DNA nanotubes for NMR structure determination of membrane proteins.

    Science.gov (United States)

    Bellot, Gaëtan; McClintock, Mark A; Chou, James J; Shih, William M

    2013-04-01

    Finding a way to determine the structures of integral membrane proteins using solution nuclear magnetic resonance (NMR) spectroscopy has proved to be challenging. A residual-dipolar-coupling-based refinement approach can be used to resolve the structure of membrane proteins up to 40 kDa in size, but to do this you need a weak-alignment medium that is detergent-resistant and it has thus far been difficult to obtain such a medium suitable for weak alignment of membrane proteins. We describe here a protocol for robust, large-scale synthesis of detergent-resistant DNA nanotubes that can be assembled into dilute liquid crystals for application as weak-alignment media in solution NMR structure determination of membrane proteins in detergent micelles. The DNA nanotubes are heterodimers of 400-nm-long six-helix bundles, each self-assembled from a M13-based p7308 scaffold strand and >170 short oligonucleotide staple strands. Compatibility with proteins bearing considerable positive charge as well as modulation of molecular alignment, toward collection of linearly independent restraints, can be introduced by reducing the negative charge of DNA nanotubes using counter ions and small DNA-binding molecules. This detergent-resistant liquid-crystal medium offers a number of properties conducive for membrane protein alignment, including high-yield production, thermal stability, buffer compatibility and structural programmability. Production of sufficient nanotubes for four or five NMR experiments can be completed in 1 week by a single individual.

  19. Structural determinants and mechanism of HIV-1 genome packaging.

    Science.gov (United States)

    Lu, Kun; Heng, Xiao; Summers, Michael F

    2011-07-22

    Like all retroviruses, the human immunodeficiency virus selectively packages two copies of its unspliced RNA genome, both of which are utilized for strand-transfer-mediated recombination during reverse transcription-a process that enables rapid evolution under environmental and chemotherapeutic pressures. The viral RNA appears to be selected for packaging as a dimer, and there is evidence that dimerization and packaging are mechanistically coupled. Both processes are mediated by interactions between the nucleocapsid domains of a small number of assembling viral Gag polyproteins and RNA elements within the 5'-untranslated region of the genome. A number of secondary structures have been predicted for regions of the genome that are responsible for packaging, and high-resolution structures have been determined for a few small RNA fragments and protein-RNA complexes. However, major questions regarding the RNA structures (and potentially the structural changes) that are responsible for dimeric genome selection remain unanswered. Here, we review efforts that have been made to identify the molecular determinants and mechanism of human immunodeficiency virus type 1 genome packaging. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Spatial structure of transition metal complexes in solution determined by EXAFS spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Erenburg, S.B. E-mail: simon@che.nsk.su; Bausk, N.V.; Zemskova, S.M.; Mazalov, L.N

    2000-06-21

    CdK EXAFS, ZnK and CuK EXAFS and XANES spectra were measured for solutions of cadmium, zinc and copper dialkyldithiocarbamates in organic solvents with varying donating abilities: tributylphosphine, methylene chloride, benzene, dibutylsulfide, pyridine, dimethylsulfoxide and for some model compounds. The parameters of the local surroundings of the Cd, Zn and Cu atoms for complex forms in solutions were determined using EXAFS spectroscopy. Spatial structure models of the complex forms in a metal chelate - nonaqueous solvent system are suggested.

  1. Spatial structure of transition metal complexes in solution determined by EXAFS spectroscopy

    International Nuclear Information System (INIS)

    Erenburg, S.B.; Bausk, N.V.; Zemskova, S.M.; Mazalov, L.N.

    2000-01-01

    CdK EXAFS, ZnK and CuK EXAFS and XANES spectra were measured for solutions of cadmium, zinc and copper dialkyldithiocarbamates in organic solvents with varying donating abilities: tributylphosphine, methylene chloride, benzene, dibutylsulfide, pyridine, dimethylsulfoxide and for some model compounds. The parameters of the local surroundings of the Cd, Zn and Cu atoms for complex forms in solutions were determined using EXAFS spectroscopy. Spatial structure models of the complex forms in a metal chelate - nonaqueous solvent system are suggested

  2. Strategy and structure in interaction: What determines the boundaries of the firm?

    OpenAIRE

    Staffan Canback; Phillip Samouel; David Price

    2003-01-01

    This paper analyzes empirically the boundaries of the firm based on Williamson's perspective on what determines firm size. It uses firm performance (risk-adjusted profitability and growth) as dependent variable; and firm organization, diseconomies of scale (atmospheric consequences, bureaucratic insularity, incentive limits, and communication distortion), economies of scale, and asset specificity as independent variables in a structural equation model. Data were collected from the 784 largest...

  3. The Effect of the Wooden Breast Myopathy on Sarcomere Structure and Organization.

    Science.gov (United States)

    Velleman, Sandra G; Clark, Daniel L; Tonniges, Jeffrey R

    2018-03-01

    The wooden breast (WB) has been classically identified by the phenotypic presence of a wood-like pectoralis major (p. major) muscle. The WB-affected p. major muscle is characterized by necrotic muscle fibers and the replacement of muscle with connective tissue, water, and fat. The objective of the current study was to determine the effect of the WB myopathy on sarcomere organization by transmission electron microscopy. Sarcomere structure and organization were examined in two broiler lines with a high incidence of WB (Lines A and B) and another broiler line without WB (Line C). Affected muscle had an increase in smaller myofibers with diameters of 20 μm or less. Sarcomere organization decreased with fiber diameter in both Lines A and B. The structure and organization of sarcomeres in Line C were similar to WB-unaffected muscle in Lines A and B. Taken together, these data demonstrate that the WB myopathy detrimentally affects sarcomere organization in a broiler line-specific manner. Disorganization of sarcomere structure will affect the function of the p. major muscle as well as meat quality.

  4. Syntheses, characterizations and crystal structures of three new organically templated or organically bonded zinc selenates

    International Nuclear Information System (INIS)

    Feng Meiling; Mao Jianggao; Song Junling

    2004-01-01

    Three new organically templated or organically bonded zinc selenates, namely, {H 2 bipy}Zn(SeO 4 ) 2 (H 2 O) 2 1 (bipy=4,4'-bipyridine), {H 2 pip}{Zn(SeO 4 ) 2 (H 2 O) 4 }·2H 2 O 2 (pip=piprazine), and Zn(SeO 4 )(phen)(H 2 O) 2 3 (phen=1,10-phenanthroline) have been synthesized by hydrothermal reactions. The structure of compound 1 features a 1D chain composed of [Zn(SeO 4 ) 2 (H 2 O) 2 ] 2- anions. Compound 2 has a 2D layer structure built from {Zn(SeO 4 ) 2 (H 2 O) 4 } 2- anions that are cross-linked by doubly protonated piperazine cations via N-H···O hydrogen bonds. The structure of compound 3 contains a 1D chain of Zn(SeO 4 )(phen)(H 2 O) 2 , such chains are further interlinked by hydrogen bonds and π···π interactions to form a layer. The different roles the templates played have also been discussed

  5. Efficient cascade multiple heterojunction organic solar cells with inverted structure

    Science.gov (United States)

    Guo, Tingting; Li, Mingtao; Qiao, Zhenfang; Yu, Leiming; Zhao, Jianhong; Feng, Nianjun; Shi, Peiguang; Wang, Xiaoyan; Pu, Xiaoyun; Wang, Hai

    2018-05-01

    In this work, we demonstrate an efficient cascade multiple heterojunction organic solar cell with inverted structure. By using two donor materials, poly(3-hexylthiosphene) (P3HT) and titanyl phthalocyanine (TiOPc), as well as two acceptor materials, [6,6]-phenyl C61 butyric acid methyl ester (PCBM) and C60, the cascade multiple heterojunctions of P3HT:PCBM/TiOPc:C60/C60 have been constructed. Applying the optimized inverted configuration of FTO/Zinc Tin Oxide (ZTO)/C60 (30 nm)/TiOPc:C60 (1:1.5, 25 nm)/P3HT:PCBM (1:0.8, 100 nm)/MoO3 (4 nm)/Ag, the considerably enhanced open circuit voltage (VOC) and short circuit current (JSC) can be harvested together, and the power conversion efficiency (PCE) is three times higher than that of the control cell with conventional structure. The significant improvements of the inverted cell are mostly due to the broadened spectral absorption and high efficient multi-interface exciton dissociation in the cascade multiple heterojunctions, indicating that the optimized cascade heterojunctions match the inverted structure well.

  6. The structure of organic langmuir films on liquid metal surfaces

    International Nuclear Information System (INIS)

    Kraack, H.; Deutsch, M.; Ocko, B.M.; Pershan, P.S.

    2003-01-01

    Langmuir films (LFs) on water have long been studied for their interest for basic science and their numerous applications in chemistry, physics, materials science and biology. We present here A-resolution synchrotron X-ray studies of the structure of stearic acid LFs on a liquid mercury surface. At low coverage, ≥110 A 2 /mol, a 2D gas phase of flat-lying molecules is observed. At high coverage, ≤23 A 2 /mol, two different hexatic phases of standing-up molecules are observed. At intermediate coverage, 52≤A≤110 A 2 /mol, novel single- and double-layered phases of flat-lying molecular dimers are found, exhibiting a 1D in-layer order. Such flat-lying phases were not hitherto observed in any LF. Measurements on LFs of fatty acids of other chain lengths indicate that this structure is generic to chain molecules on mercury, although the existence of some of the flat-lying phases, and the observed phase sequence, depend on the chain length. Organic LFs on Hg, and in particular the new flat-lying phases, should provide a broader nano-structural tunability range for molecular electronic device construction than most solid-supported self-assembled monolayers used at present

  7. Defining an essence of structure determining residue contacts in proteins.

    Science.gov (United States)

    Sathyapriya, R; Duarte, Jose M; Stehr, Henning; Filippis, Ioannis; Lappe, Michael

    2009-12-01

    The network of native non-covalent residue contacts determines the three-dimensional structure of a protein. However, not all contacts are of equal structural significance, and little knowledge exists about a minimal, yet sufficient, subset required to define the global features of a protein. Characterisation of this "structural essence" has remained elusive so far: no algorithmic strategy has been devised to-date that could outperform a random selection in terms of 3D reconstruction accuracy (measured as the Ca RMSD). It is not only of theoretical interest (i.e., for design of advanced statistical potentials) to identify the number and nature of essential native contacts-such a subset of spatial constraints is very useful in a number of novel experimental methods (like EPR) which rely heavily on constraint-based protein modelling. To derive accurate three-dimensional models from distance constraints, we implemented a reconstruction pipeline using distance geometry. We selected a test-set of 12 protein structures from the four major SCOP fold classes and performed our reconstruction analysis. As a reference set, series of random subsets (ranging from 10% to 90% of native contacts) are generated for each protein, and the reconstruction accuracy is computed for each subset. We have developed a rational strategy, termed "cone-peeling" that combines sequence features and network descriptors to select minimal subsets that outperform the reference sets. We present, for the first time, a rational strategy to derive a structural essence of residue contacts and provide an estimate of the size of this minimal subset. Our algorithm computes sparse subsets capable of determining the tertiary structure at approximately 4.8 A Ca RMSD with as little as 8% of the native contacts (Ca-Ca and Cb-Cb). At the same time, a randomly chosen subset of native contacts needs about twice as many contacts to reach the same level of accuracy. This "structural essence" opens new avenues in the

  8. State of the APC/C: Organization, function, and structure

    Science.gov (United States)

    McLean, Janel R.; Chaix, Denis; Ohi, Melanie D.; Gould, Kathleen L.

    2016-01-01

    The ubiquitin-proteasome protein degradation system is involved in many essential cellular processes including cell cycle regulation, cell differentiation, and the unfolded protein response.The anaphase-promoting complex/cyclosome (APC/C), an evolutionary conserved E3 ubiquitin ligase, was discovered 15 years ago because of its pivotal role in cyclin degradation and mitotic progression. Since then, we have learned that the APC/C is a very large, complex E3 ligase composed of 13 subunits, yielding a molecular machine of approximately 1 MDa. The intricate regulation of the APC/C is mediated by the Cdc20 family of activators, pseudosubstrate inhibitors, protein kinases and phosphatases and the spindle assembly checkpoint. The large size, complexity, and dynamic nature of the APC/C represent significant obstacles toward high-resolution structural techniques; however, over the last decade, there have been a number of lower resolution APC/C structures determined using single particle electron microscopy. These structures, when combined with data generated from numerous genetic and biochemical studies, have begun to shed light on how APC/C activity is regulated. Here, we discuss the most recent developments in the APC/C field concerning structure, substrate recognition, and catalysis. PMID:21261459

  9. Structure of Solvent-Free Nanoparticle−Organic Hybrid Materials

    KAUST Repository

    Yu, Hsiu-Yu

    2010-11-16

    We derive the radial distribution function and the static structure factor for the particles in model nanoparticleorganic hybrid materials composed of nanoparticles and attached oligomeric chains in the absence of an intervening solvent. The assumption that the oligomers form an incompressible fluid of bead-chains attached to the particles that is at equilibrium for a given particle configuration allows us to apply a density functional theory for determining the equilibrium configuration of oligomers as well as the distribution function of the particles. A quasi-analytic solution is facilitated by a regular perturbation analysis valid when the oligomer radius of gyration R g is much greater than the particle radius a. The results show that the constraint that each particle carries its own share of the fluid attached to itself yields a static structure factor that approaches zero as the wavenumber approaches zero. This result indicates that each particle excludes exactly one other particle from its neighborhood. © 2010 American Chemical Society.

  10. Assessment of carotid plaque vulnerability using structural and geometrical determinants

    International Nuclear Information System (INIS)

    Li, Z.Y.; Tang, T.; U-King-Im, J.; Graves, M.; Gillard, J.H.; Sutcliffe, M.

    2008-01-01

    Because many acute cerebral ischemic events are caused by rupture of vulnerable carotid atheroma and subsequent thrombosis, the present study used both idealized and patient-specific carotid atheromatous plaque models to evaluate the effect of structural determinants on stress distributions within plaque. Using a finite element method, structural analysis was performed using models derived from in vivo high-resolution magnetic resonance imaging (MRI) of carotid atheroma in 40 non-consecutive patients (20 symptomatic, 20 asymptomatic). Plaque components were modeled as hyper-elastic materials. The effects of varying fibrous cap thickness, lipid core size and lumen curvature on plaque stress distributions were examined. Lumen curvature and fibrous cap thickness were found to be major determinants of plaque stress. The size of the lipid core did not alter plaque stress significantly when the fibrous cap was relatively thick. The correlation between plaque stress and lumen curvature was significant for both symptomatic (p=0.01; correlation coefficient: 0.689) and asymptomatic patients (p=0.01; correlation coefficient: 0.862). Lumen curvature in plaques of symptomatic patients was significantly larger than those of asymptomatic patients (1.50±1.0 mm -1 vs 1.25±0.75 mm -1 ; p=0.01). Specific plaque morphology (large lumen curvature and thin fibrous cap) is closely related to plaque vulnerability. Structural analysis using high-resolution MRI of carotid atheroma may help in detecting vulnerable atheromatous plaque and aid the risk stratification of patients with carotid disease. (author)

  11. X-ray structure determination and deuteration of nattokinase.

    Science.gov (United States)

    Yanagisawa, Yasuhide; Chatake, Toshiyuki; Naito, Sawa; Ohsugi, Tadanori; Yatagai, Chieko; Sumi, Hiroyuki; Kawaguchi, Akio; Chiba-Kamosida, Kaori; Ogawa, Megumi; Adachi, Tatsumi; Morimoto, Yukio

    2013-11-01

    Nattokinase (NK) is a strong fibrinolytic enzyme, which is produced in abundance by Bacillus subtilis natto. Although NK is a member of the subtilisin family, it displays different substrate specificity when compared with other subtilisins. The results of molecular simulations predict that hydrogen arrangements around Ser221 at the active site probably account for the substrate specificity of NK. Therefore, neutron crystallographic analysis should provide valuable information that reveals the enzymatic mechanism of NK. In this report, the X-ray structure of the non-hydrogen form of undeuterated NK was determined, and the preparation of deuterated NK was successfully achieved. The non-hydrogen NK structure was determined at 1.74 Å resolution. The three-dimensional structures of NK and subtilisin E from Bacillus subtilis DB104 are near identical. Deuteration of NK was carried out by cultivating Bacillus subtilis natto in deuterated medium. The D2O resistant strain of Bacillus subtilis natto was obtained by successive cultivation rounds, in which the concentration of D2O in the medium was gradually increased. NK was purified from the culture medium and its activity was confirmed by the fibrin plate method. The results lay the framework for neutron protein crystallography analysis.

  12. Primary structure, gene organization and polypeptide expression of poliovirus RNA

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, N. (State Univ. of New York, Stony Brook); Semler, B.L.; Rothberg, P.G.

    1981-06-18

    The primary structure of the poliovirus genome has been determined. The RNA molecule is 7433 nucleotides long, polyadenylated at the 3' terminus, and covalently linked to a small protein (VPg) at the 5' terminus. An open reading frame of 2207 consecutive triplets spans over 89% of the nucleotide sequence and codes for the viral polyprotein NCVPOO. Twelve viral polypeptides have been mapped by amino acid sequence analysis and were found to be proteolytic cleavage products of the polyprotein, cleavages occurring predominantly at Gln-Gly pairs.

  13. Structure, Organization, and Delivery of Critical Care in Asian ICUs.

    Science.gov (United States)

    Arabi, Yaseen M; Phua, Jason; Koh, Younsuck; Du, Bin; Faruq, Mohammad Omar; Nishimura, Masaji; Fang, Wen-Feng; Gomersall, Charles; Al Rahma, Hussain N; Tamim, Hani; Al-Dorzi, Hasan M; Al-Hameed, Fahad M; Adhikari, Neill K J; Sadat, Musharaf

    2016-10-01

    Despite being the epicenter of recent pandemics, little is known about critical care in Asia. Our objective was to describe the structure, organization, and delivery in Asian ICUs. A web-based survey with the following domains: hospital organizational characteristics, ICU organizational characteristics, staffing, procedures and therapies available in the ICU and written protocols and policies. ICUs from 20 Asian countries from April 2013 to January 2014. Countries were divided into low-, middle-, and high-income based on the 2011 World Bank Classification. ICU directors or representatives. Of 672 representatives, 335 (50%) responded. The average number of hospital beds was 973 (SE of the mean [SEM], 271) with 9% (SEM, 3%) being ICU beds. In the index ICUs, the average number of beds was 21 (SEM, 3), of single rooms 8 (SEM, 2), of negative-pressure rooms 3 (SEM, 1), and of board-certified intensivists 7 (SEM, 3). Most ICUs (65%) functioned as closed units. The nurse-to-patient ratio was 1:1 or 1:2 in most ICUs (84%). On multivariable analysis, single rooms were less likely in low-income countries (p = 0.01) and nonreferral hospitals (p = 0.01); negative-pressure rooms were less likely in private hospitals (p = 0.03) and low-income countries (p = 0.005); 1:1 nurse-to-patient ratio was lower in private hospitals (p = 0.005); board-certified intensivists were less common in low-income countries (p structure, organization, and delivery in Asia, which was related to hospital funding source and size, and country income. The lack of single and negative-pressure rooms in many Asian ICUs should be addressed before any future pandemic of severe respiratory illness.

  14. Structural versatility of Metal-organic frameworks: Synthesis and Characterization

    KAUST Repository

    Alsadun, Norah S.

    2017-05-01

    Metal-Organic Frameworks (MOFs), an emerging class of porous crystalline materials, have shown promising properties for diverse applications such as catalysis, gas storage and separation. The high degree of tunability of MOFs vs other solid materials enable the assembly of advanced materials with fascinating properties for specific applications. Nevertheless, the precise control in the construction of MOFs at the molecular level remains challenging. Particularly, the formation of pre-targeted multi-nuclear Molecular Building Block (MBB) precursors to unveil materials with targeted structural characteristics is captivating. The aim of my master project in the continuous quest of the group of Prof. Eddaoudi in exploring different synthetic pathways to control the assembly of Rare Earth (RE) based MOF. After giving a general overview about MOFs, I will discuss in this thesis the results of my work on the use of tri-topic oriented organic carboxylate building units with the aim to explore the assembly/construction of new porous RE based MOFs. In chapter 2 will discuss the assembly of 3-c linkers with RE metals was then evaluated based on symmetry and angularity of the three connected linkers. The focus of chapter 3 is cerium based MOFs and heterometallic system, based on 3-c ligands with different length and symmetry. Overall, the incompatibility of 3-c ligands with the 12-c cuo MBB did not allow to any formation of higher neuclearity (˃6), but it has resulted in affecting the connectivity of the cluster.

  15. Leveraging structure determination with fragment screening for infectious disease drug targets: MECP synthase from Burkholderia pseudomallei

    Energy Technology Data Exchange (ETDEWEB)

    Begley, Darren W.; Hartley, Robert C.; Davies, Douglas R.; Edwards, Thomas E.; Leonard, Jess T.; Abendroth, Jan; Burris, Courtney A.; Bhandari, Janhavi; Myler, Peter J.; Staker, Bart L.; Stewart, Lance J. (UWASH); (Emerald)

    2011-09-28

    As part of the Seattle Structural Genomics Center for Infectious Disease, we seek to enhance structural genomics with ligand-bound structure data which can serve as a blueprint for structure-based drug design. We have adapted fragment-based screening methods to our structural genomics pipeline to generate multiple ligand-bound structures of high priority drug targets from pathogenic organisms. In this study, we report fragment screening methods and structure determination results for 2C-methyl-D-erythritol-2,4-cyclo-diphosphate (MECP) synthase from Burkholderia pseudomallei, the gram-negative bacterium which causes melioidosis. Screening by nuclear magnetic resonance spectroscopy as well as crystal soaking followed by X-ray diffraction led to the identification of several small molecules which bind this enzyme in a critical metabolic pathway. A series of complex structures obtained with screening hits reveal distinct binding pockets and a range of small molecules which form complexes with the target. Additional soaks with these compounds further demonstrate a subset of fragments to only bind the protein when present in specific combinations. This ensemble of fragment-bound complexes illuminates several characteristics of MECP synthase, including a previously unknown binding surface external to the catalytic active site. These ligand-bound structures now serve to guide medicinal chemists and structural biologists in rational design of novel inhibitors for this enzyme.

  16. A use of Ramachandran potentials in protein solution structure determinations

    International Nuclear Information System (INIS)

    Bertini, Ivano; Cavallaro, Gabriele; Luchinat, Claudio; Poli, Irene

    2003-01-01

    A strategy is developed to use database-derived φ-ψ constraints during simulated annealing procedures for protein solution structure determination in order to improve the Ramachandran plot statistics, while maintaining the agreement with the experimental constraints as the sole criterion for the selection of the family. The procedure, fully automated, consists of two consecutive simulated annealing runs. In the first run, the database-derived φ-ψ constraints are enforced for all aminoacids (but prolines and glycines). A family of structures is then selected on the ground of the lowest violations of the experimental constraints only, and the φ-ψ values for each residue are examined. In the second and final run, the database-derived φ-ψ constraints are enforced only for those residues which in the first run have ended in one and the same favored φ-ψ region. For residues which are either spread over different favored regions or concentrated in disallowed regions, the constraints are not enforced. The final family is then selected, after the second run, again only based on the agreement with the experimental constraints. This automated approach was implemented in DYANA and was tested on as many as 12 proteins, including some containing paramagnetic metals, whose structures had been previously solved in our laboratory. The quality of the structures, and of Ramachandran plot statistics in particular, was notably improved while preserving the agreement with the experimental constraints

  17. What determines the structures of native folds of proteins?

    International Nuclear Information System (INIS)

    Trovato, Antonio; Hoang, Trinh X; Banavar, Jayanth R; Maritan, Amos; Seno, Flavio

    2005-01-01

    We review a simple physical model (Hoang et al 2004 Proc. Natl Acad. Sci. USA 101 7960, Banavar et al 2004 Phys. Rev. E at press) which captures the essential physico-chemical ingredients that determine protein structure, such as the inherent anisotropy of a chain molecule, the geometrical and energetic constraints placed by hydrogen bonds, sterics, and hydrophobicity. Within this framework, marginally compact conformations resembling the native state folds of proteins emerge as competing minima in the free energy landscape. Here we demonstrate that a hydrophobic-polar (HP) sequence composed of regularly repeated patterns has as its ground state a β-helical structure remarkably similar to a known architecture in the Protein Data Bank

  18. Host Proteins Determine MRSA Biofilm Structure and Integrity

    DEFF Research Database (Denmark)

    Dreier, Cindy; Nielsen, Astrid; Jørgensen, Nis Pedersen

    Human extracellular matrix (hECM) proteins aids the initial attachment and initiation of an infection, by specific binding to bacterial cell surface proteins. However, the importance of hECM proteins in structure, integrity and antibiotic resilience of a biofilm is unknown. This study aims...... to determine how specific hECM proteins affect S. aureus USA300 JE2 biofilms. Biofilms were grown in the presence of synovial fluid from rheumatoid arteritis patients to mimic in vivo conditions, where bacteria incorporate hECM proteins into the biofilm matrix. Difference in biofilm structure, with and without...... addition of hECM to growth media, was visualized by confocal laser scanning microscopy. Two enzymatic degradation experiments were used to study biofilm matrix composition and importance of hECM proteins: enzymatic removal of specific hECM proteins from growth media, before biofilm formation, and enzymatic...

  19. Cellulose synthase complex organization and cellulose microfibril structure.

    Science.gov (United States)

    Turner, Simon; Kumar, Manoj

    2018-02-13

    Cellulose consists of linear chains of β-1,4-linked glucose units, which are synthesized by the cellulose synthase complex (CSC). In plants, these chains associate in an ordered manner to form the cellulose microfibrils. Both the CSC and the local environment in which the individual chains coalesce to form the cellulose microfibril determine the structure and the unique physical properties of the microfibril. There are several recent reviews that cover many aspects of cellulose biosynthesis, which include trafficking of the complex to the plasma membrane and the relationship between the movement of the CSC and the underlying cortical microtubules (Bringmann et al. 2012 Trends Plant Sci. 17 , 666-674 (doi:10.1016/j.tplants.2012.06.003); Kumar & Turner 2015 Phytochemistry 112 , 91-99 (doi:10.1016/j.phytochem.2014.07.009); Schneider et al. 2016 Curr. Opin. Plant Biol. 34 , 9-16 (doi:10.1016/j.pbi.2016.07.007)). In this review, we will focus on recent advances in cellulose biosynthesis in plants, with an emphasis on our current understanding of the structure of individual catalytic subunits together with the local membrane environment where cellulose synthesis occurs. We will attempt to relate this information to our current knowledge of the structure of the cellulose microfibril and propose a model in which variations in the structure of the CSC have important implications for the structure of the cellulose microfibril produced.This article is part of a discussion meeting issue 'New horizons for cellulose nanotechnology'. © 2017 The Author(s).

  20. Purification and primary structure determination of human lysosomal dipeptidase.

    Science.gov (United States)

    Dolenc, Iztok; Mihelic, Marko

    2003-02-01

    The lysosomal metallopeptidase is an enzyme that acts preferentially on dipeptides with unsubstituted N- and C-termini. Its activity is highest in slightly acidic pH. Here we describe the isolation and characterization of lysosomal dipeptidase from human kidney. The isolated enzyme has the amino-terminal sequence DVAKAIINLAVY and is a homodimer with a molecular mass of 100 kDa. So far no amino acid sequence has been determined for this metallopeptidase. The complete primary structure as deduced from the nucleotide sequence revealed that the isolated dipeptidase is similar to blood plasma glutamate carboxypeptidase.

  1. Structure determination of spider silk from X-ray images

    Energy Technology Data Exchange (ETDEWEB)

    Ulrich, Stephan; Zippelius, Annette [Universitaet Goettingen, Institut fuer Theoretische Physik (Germany); Meling, Martin [Max-Planck-Institut fuer biophysikalische Chemie, Goettingen (Germany); Glisovic, Anja; Salditt, Tim [Universitaet Goettingen, Institut fuer Roentgenphysik (Germany)

    2008-07-01

    Spider silk consists of interconnected crystallites, which are typically aligned along the fiber axis. We present a method to systematically determine the structure of these crystallites. Hereby we introduce a model that calculates the scattering function G(q) which is fitted to the measured X-ray image (silk from nephila clavipes). With it, the crystallites' size, the constitution and dimensions of their unit cell, as well as their tilt with respect to the fiber axis is identified, and furthermore the effect of coherent scattering from different crystallites is investigated. The shown methods and the presented model can easily be generalized to a wide class of composite materials.

  2. Shallow lunar structure determined from the passive seismic experiment

    International Nuclear Information System (INIS)

    Nakamura, Y.; Dorman, J.; Duennebier, F.; Lammlein, D.; Latham, G.

    1975-01-01

    Data relevant to the shallow structure of the Moon obtained at the Apollo seismic stations are compared with previously published results of the active seismic experiments. It is concluded that the lunar surface is covered by a layer of low seismic velocity (Vsub(p) approximately equal to 100 ms -1 ), which appears to be equivalent to the lunar regolith defined previously by geological observations. This layer is underlain by a zone of distinctly higher seismic velocity at all of the Apollo landing sites. The regolith thicknesses at the Apollo 11, 12, and 15 sites are estimated from the shear-wave resonance to be 4.4, 3.7, and 4.4m, respectively. These thicknesses and those determined at the other Apollo sites by the active seismic experiments appear to be correlated with the age determinations and the abundances of extra-lunar components at the sites. (Auth.)

  3. Adaptive symbiotic organisms search (SOS algorithm for structural design optimization

    Directory of Open Access Journals (Sweden)

    Ghanshyam G. Tejani

    2016-07-01

    Full Text Available The symbiotic organisms search (SOS algorithm is an effective metaheuristic developed in 2014, which mimics the symbiotic relationship among the living beings, such as mutualism, commensalism, and parasitism, to survive in the ecosystem. In this study, three modified versions of the SOS algorithm are proposed by introducing adaptive benefit factors in the basic SOS algorithm to improve its efficiency. The basic SOS algorithm only considers benefit factors, whereas the proposed variants of the SOS algorithm, consider effective combinations of adaptive benefit factors and benefit factors to study their competence to lay down a good balance between exploration and exploitation of the search space. The proposed algorithms are tested to suit its applications to the engineering structures subjected to dynamic excitation, which may lead to undesirable vibrations. Structure optimization problems become more challenging if the shape and size variables are taken into account along with the frequency. To check the feasibility and effectiveness of the proposed algorithms, six different planar and space trusses are subjected to experimental analysis. The results obtained using the proposed methods are compared with those obtained using other optimization methods well established in the literature. The results reveal that the adaptive SOS algorithm is more reliable and efficient than the basic SOS algorithm and other state-of-the-art algorithms.

  4. Structure and organization of nanosized-inclusion-containing bilayer membranes

    Science.gov (United States)

    Ren, Chun-Lai; Ma, Yu-Qiang

    2009-07-01

    Based on a considerable amount of experimental evidence for lateral organization of lipid membranes which share astonishingly similar features in the presence of different inclusions, we use a hybrid self-consistent field theory (SCFT)/density-functional theory (DFT) approach to deal with bilayer membranes embedded by nanosized inclusions and explain experimental findings. Here, the hydrophobic inclusions are simple models of hydrophobic drugs or other nanoparticles for biomedical applications. It is found that lipid/inclusion-rich domains are formed at moderate inclusion concentrations and disappear with the increase in the concentration of inclusions. At high inclusion content, chaining of inclusions occurs due to the effective depletion attraction between inclusions mediated by lipids. Meanwhile, the increase in the concentration of inclusions can also cause thickening of the membrane and the distribution of inclusions undergoes a layering transition from one-layer structure located in the bilayer midplane to two-layer structure arranged into the two leaflets of a bilayer. Our theoretical predictions address the complex interactions between membranes and inclusions suggesting a unifying mechanism which reflects the competition between the conformational entropy of lipids favoring the formation of lipid- and inclusion-rich domains in lipids and the steric repulsion of inclusions leading to the uniform dispersion.

  5. Chemical-Structural Changes of Organic Matter in a Semi-Arid Soil After Organic Amendment

    Institute of Scientific and Technical Information of China (English)

    C.NICOL(A)S; G.MASCIANDARO; T.HERN(A)NDEZ; C.GARCIA

    2012-01-01

    A 9-month incubation experiment using composted and non-composted amendments derived from vine pruning waste and sewage sludge was carried out to study the effects of the nature and stability of organic amendments on the structural composition of organic matter (OM) in a semi-arid soil. The changes of soil OM,both in the whole soil and in the extractable carbon with pyrophosphate,were evaluated by pyrolysis-gas chromatography and chemical analyses.By the end of the experiment,the soils amended with pruning waste exhibited less organic carbon loss than those receiving sewage sludge.The non-composted residues increased the aliphatic-pyrolytic products of the OM,both in the whole soil and also in the pyrophosphate extract,with the products derived from peptides and proteins being significantly higher.After 9 months,in the soils amended with pruning waste the relative abundance of phenolic-pyrolytic products derived from phenolic compounds,lignin and proteins in the whole soil tended to increase more than those in the soils amended with sewage sludge.However,the extractable OM with pyrophosphate in the soils amended with composted residues tended to have higher contents of these phenolic-pyrolytic products than that in non-composted ones.Thus,despite the stability of pruning waste,the composting of this material promoted the incorporation of phenolic compounds to the soil OM.The pyrolytic indices (furfural/pyrrole and aliphatic/aromatic ratios) showed the diminution of aliphatic compounds and the increase of aromatic compounds,indicating the stabilization of the OM in the amended soils after 9 months.In conclusion,the changes of soil OM depend on the nature and stability of the organic amendments,with composted vine pruning waste favouring humification.

  6. Ethical challenges for accountable care organizations: a structured review.

    Science.gov (United States)

    DeCamp, Matthew; Farber, Neil J; Torke, Alexia M; George, Maura; Berger, Zackary; Keirns, Carla C; Kaldjian, Lauris C

    2014-10-01

    Accountable care organizations (ACOs) are proliferating as a solution to the cost crisis in American health care, and already involve as many as 31 million patients. ACOs hold clinicians, group practices, and in many circumstances hospitals financially accountable for reducing expenditures and improving their patients' health outcomes. The structure of health care affects the ethical issues arising in the practice of medicine; therefore, like all health care organizational structures, ACOs will experience ethical challenges. No framework exists to assist key ACO stakeholders in identifying or managing these challenges. We conducted a structured review of the medical ACO literature using qualitative content analysis to inform identification of ethical challenges for ACOs. Our analysis found infrequent discussion of ethics as an explicit concern for ACOs. Nonetheless, we identified nine critical ethical challenges, often described in other terms, for ACO stakeholders. Leaders could face challenges regarding fair resource allocation (e.g., about fairly using ACOs' shared savings), protection of professionals' ethical obligations (especially related to the design of financial incentives), and development of fair decision processes (e.g., ensuring that beneficiary representatives on the ACO board truly represent the ACO's patients). Clinicians could perceive threats to their professional autonomy (e.g., through cost control measures), a sense of dual or conflicted responsibility to their patients and the ACO, or competition with other clinicians. For patients, critical ethical challenges will include protecting their autonomy, ensuring privacy and confidentiality, and effectively engaging them with the ACO. ACOs are not inherently more or less "ethical" than other health care payment models, such as fee-for-service or pure capitation. ACOs' nascent development and flexibility in design, however, present a time-sensitive opportunity to ensure their ethical operation

  7. Geometry-driven cell organization determines tissue growths in scaffold pores: consequences for fibronectin organization.

    Directory of Open Access Journals (Sweden)

    Pascal Joly

    Full Text Available To heal tissue defects, cells have to bridge gaps and generate new extracellular matrix (ECM. Macroporous scaffolds are frequently used to support the process of defect filling and thus foster tissue regeneration. Such biomaterials contain micro-voids (pores that the cells fill with their own ECM over time. There is only limited knowledge on how pore geometry influences cell organization and matrix production, even though it is highly relevant for scaffold design. This study hypothesized that 1 a simple geometric description predicts cellular organization during pore filling at the cell level and that 2 pore closure results in a reorganization of ECM. Scaffolds with a broad distribution of pore sizes (macroporous starPEG-heparin cryogel were used as a model system and seeded with primary fibroblasts. The strategies of cells to fill pores could be explained by a simple geometrical model considering cells as tensioned chords. The model matched qualitatively as well as quantitatively by means of cell number vs. open cross-sectional area for all pore sizes. The correlation between ECM location and cell position was higher when the pores were not filled with tissue (Pearson's coefficient ρ = 0.45±0.01 and reduced once the pores were closed (ρ = 0.26±0.04 indicating a reorganization of the cell/ECM network. Scaffold pore size directed the time required for pore closure and furthermore impacted the organization of the fibronectin matrix. Understanding how cells fill micro-voids will help to design biomaterial scaffolds that support the endogenous healing process and thus allow a fast filling of tissue defects.

  8. Effect of organ donation after circulatory determination of death on number of organ transplants from donors with neurologic determination of death

    Science.gov (United States)

    Rao, Vivek; Dhanani, Sonny; MacLean, Janet; Payne, Clare; Paltser, Elizabeth; Humar, Atul; Zaltzman, Jeffrey

    2017-01-01

    BACKGROUND: To increase the available pool of organ donors, Ontario introduced donation after circulatory determination of death (DCD) in 2006. Other jurisdictions have reported a decrease in donations involving neurologic determination of death (NDD) after implementation of DCD, with a drop in organ yield and quality. In this study, we examined the effect of DCD on overall transplant activity in Ontario. METHODS: We examined deceased donor and organ transplant activity during 3 distinct 4-year eras: pre-DCD (2002/03 to 2005/06), early DCD (2006/07 to 2009/10) and recent DCD (2010/11 to 2013/14). We compared these donor groups by categorical characteristics. RESULTS: Donation increased by 57%, from 578 donors in the pre-DCD era to 905 donors in the recent DCD era, with a 21% proportion (190/905) of DCD donors in the recent DCD era. However, overall NDD donation also increased. The mean length of hospital stay before declaration for NDD was 2.7 days versus 6.0 days before withdrawal of life support and subsequent asystole in cases of DCD. The average organ yield was 3.73 with NDD donation versus 2.58 with DCD (p organs from DCD donors were successfully transplanted. From the pre-DCD era to the recent DCD era, transplant activity in each era increased for all solid-organ recipients, including heart (from 158 to 216), kidney (from 821 to 1321), liver (from 477 to 657) and lung (from 160 to 305). INTERPRETATION: Implementation of DCD in Ontario led to increased transplant activity for all solid-organ recipients. There was no evidence that the use of DCD was pre-empting potential NDD donation. In contrast to groups receiving other organs, heart transplant candidates have not yet benefited from DCD. PMID:28947546

  9. Soil structure and microbial activity dynamics in 20-month field-incubated organic-amended soils

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Schjønning, Per; Møldrup, Per

    2014-01-01

    to determine compressive strength. During incubation, the amount of WDC depended on soil carbon content while the trends correlated with moisture content. Organic amendment only yielded modest decreases (mean of 14% across all sampling times and soils) in WDC, but it was sufficient to stimulate the microbial......Soil structure formation is essential to all soil ecosystem functions and services. This study aims to quantify changes in soil structure and microbial activity during and after field incubation and examine the effect of carbon, organic amendment and clay on aggregate characteristics. Five soils...... community (65–100% increase in FDA). Incubation led to significant macroaggregate formation (>2 mm) for all soils. Friability and strength of newly-formed aggregates were negatively correlated with clay content and carbon content, respectively. Soil workability was best for the kaolinite-rich soil...

  10. Effects of organic enrichment on macrofauna community structure: an experimental approach

    Directory of Open Access Journals (Sweden)

    Rodrigo Riera

    2013-12-01

    Full Text Available The determination of the resilience of benthic assemblages is a capital issue for the off-shore aquaculture industry in its attempts to minimize environmental disturbances. Experimental studies are an important tool for the establishment of thresholds for macrofaunal assemblages inhabiting sandy seabeds. An experiment was conducted with three treatments (Control, 1x and 3x,in which organic load (fish pellets was added (1x (10 g of fish pellets and 3x (30 g. A reduction in abundance of individuals and species richness was found as between the control and organic-enriched treatments. Significant changes in assemblage structure were also found, mainly due to the decrease of the sensitive tanaid Apseudes talpa in organically-enriched treatments. AMBI and M-AMBI indices were calculated and a decrease of ecological status was observed in treatment 3x.

  11. Filament structure, organization, and dynamics in MreB sheets.

    Science.gov (United States)

    Popp, David; Narita, Akihiro; Maeda, Kayo; Fujisawa, Tetsuro; Ghoshdastider, Umesh; Iwasa, Mitsusada; Maéda, Yuichiro; Robinson, Robert C

    2010-05-21

    In vivo fluorescence microscopy studies of bacterial cells have shown that the bacterial shape-determining protein and actin homolog, MreB, forms cable-like structures that spiral around the periphery of the cell. The molecular structure of these cables has yet to be established. Here we show by electron microscopy that Thermatoga maritime MreB forms complex, several mum long multilayered sheets consisting of diagonally interwoven filaments in the presence of either ATP or GTP. This architecture, in agreement with recent rheological measurements on MreB cables, may have superior mechanical properties and could be an important feature for maintaining bacterial cell shape. MreB polymers within the sheets appear to be single-stranded helical filaments rather than the linear protofilaments found in the MreB crystal structure. Sheet assembly occurs over a wide range of pH, ionic strength, and temperature. Polymerization kinetics are consistent with a cooperative assembly mechanism requiring only two steps: monomer activation followed by elongation. Steady-state TIRF microscopy studies of MreB suggest filament treadmilling while high pressure small angle x-ray scattering measurements indicate that the stability of MreB polymers is similar to that of F-actin filaments. In the presence of ADP or GDP, long, thin cables formed in which MreB was arranged in parallel as linear protofilaments. This suggests that the bacterial cell may exploit various nucleotides to generate different filament structures within cables for specific MreB-based functions.

  12. Simple surface structure determination from Fourier transforms of angle-resolved photoemission extended fine structure

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Y. [Pennsylvania State Univ., University Park, PA (United States)]|[Lawrence Berkeley Lab., CA (United States); Shirley, D.A. [Pennsylvania State Univ., University Park, PA (United States)

    1995-02-01

    The authors show by Fourier analyses of experimental data, with no further treatment, that the positions of all the strong peaks in Fourier transforms of angle-resolved photoemission extended fine structure (ARPEFS) from adsorbed surfaces can be explicitly predicted from a trial structure with an accuracy of about {+-} 0.3 {angstrom} based on a single-scattering cluster model together with the concept of a strong backscattering cone, and without any additional analysis. This characteristic of ARPEFS Fourier transforms can be developed as a simple method for determining the structures of adsorbed surfaces to an accuracy of about {+-} 0.1 {angstrom}.

  13. Organic Photovoltaic Structures as Photo-active Electrodes

    International Nuclear Information System (INIS)

    Gustafson, Matthew P.; Clark, Noel; Winther-Jensen, Bjorn; MacFarlane, Douglas R.

    2014-01-01

    This study demonstrated the novel use of a bulk heterojunction (BHJ), as present in modern organic solar cells, as a light-assisted electrocatalyst for water electrolysis reactions. Two separate organic photo-voltaic electrode structures were designed for targeting both the reduction, (ITO-PET/PEDOT:PSS/P3HT:PCBM)* and oxidation, (ITO-PET/ZnO/P3HT:PCBM)* reactions of water, denoted as OPE-R and OPE-O respectively. The OPE-R electrode supported both the proton reduction reaction (PRR) and oxygen reduction reaction (ORR) achieving photocurrents of -0.04 mAcm −2 (ORR) and -0.03 mAcm −2 (PRR) and a photovoltage of 0.50 V (ORR) and onset photovoltage at -0.59 V (PRR). By comparison, the OPE-O electrode achieved photocurrents of 0.15 mAcm −2 and photovoltages of 0.35 V for the water oxidation reaction (WOR). Both BHJ designs confirmed evidence of photo-enhanced Bulk Heterojunction Electrode (BHE) activity. The stability and sources of electrode degradation were also studied, with the OPE-O electrode proving to be more stable than the OPE-R electrode, most likely due to the PEDOT:PSS layer and PSS migration in the presence of water. *Indium Tin Oxide (ITO), Polyethylene Terephthalate (PET), Poly(3,4-ethylenedioxythiophene) (PEDOT), Polystyrenesulfonate acid (PSS), Poly(3-hexylthiophene) (P3HT), Phenyl-C 61 -Butyric acid Methyl ester (PCBM), Zinc Oxide (ZnO)

  14. Spectrographic determination of metallic impurities in organic coolants for nuclear reactors

    International Nuclear Information System (INIS)

    Martin Munoz, M.; Alvarez Gonzalez, F.

    1969-01-01

    A spectrochemical method for determining metallic impurities in organic coolants for nuclear reactors is given. The organic matter in solid samples is eliminated by controlled distillation and dry ashing in the presence of magnesium oxide as carrier. Liquid, samples are vacuum distillated. The residue is analyzed by carrier distillation and by total burning techniques. The analytical results are discussed and compared with those obtained destroying the organic matter without carrier and using the copper spark technique. (Author) 12 refs

  15. Determination of uranium in organic phase by flow injection spectrophotometric analysis

    International Nuclear Information System (INIS)

    Yu Yiyun

    1998-01-01

    Based on the use of merging zone circuit and simulating a series of standard solution of uranium in organic phase, uranium in unknown organic phase sample was determined by flow injection spectrophotometry. A linear calibration graph was obtained with correlation coefficient of 0.999 for uranium concentration in organic phase over 10∼200 mg/L. Isopropyl alcohol was used as carrier solution. Mixing colour solution contains isopropyl alcohol, triethanolamine, masking reagent and Br-PADAP. The relative standard deviation of the method was better than +-5%. Determination of each sample can be completed in one minute. The method characteristic is: (1) using merging zone and simulating standard solution of uranium in organic phase, the method is sensitive and reliable; (2) even if the determined solution was in turbid condition, it can be quantitatively determined; (3) by means of solution replace technique, the tube of peristaltic pump can be used over a long period of time

  16. Chordotonal organs in hemipteran insects: unique peripheral structures but conserved central organization revealed by comparative neuroanatomy.

    Science.gov (United States)

    Nishino, Hiroshi; Mukai, Hiromi; Takanashi, Takuma

    2016-12-01

    Hemipteran insects use sophisticated vibrational communications by striking body appendages on the substrate or by oscillating the abdominal tymbal. There has been, however, little investigation of sensory channels for processing vibrational signals. Using sensory nerve stainings and low invasive confocal analyses, we demonstrate the comprehensive neuronal mapping of putative vibration-responsive chordotonal organs (COs) in stink bugs (Pentatomidae and Cydinidae) and cicadas (Cicadidae). The femoral CO (FCO) in stink bugs consists of ventral and dorsal scoloparia, homologous to distal and proximal scoloparia in locusts, which are implicated in joint movement detection and vibration detection, respectively. The ligament of the dorsal scoloparium is distally attached to the accessory extensor muscle, whereas that of the ventral scoloparium is attached to a specialized tendon. Their afferents project to the dorso-lateral neuropil and the central region of the medial ventral association center (mVAC) in the ipsilateral neuromere, where presumed dorsal scoloparium afferents and subgenual organ afferents are largely intermingled. In contrast, FCOs in cicadas have decreased dorsal scoloparium neurons and lack projections to the mVAC. The tymbal CO of stink bugs contains four sensory neurons that are distally attached to fat body cells via a ligament. Their axons project intersegmentally to the dorsal region of mVACs in all neuromeres. Together with comparisons of COs in different insect groups, the results suggest that hemipteran COs have undergone structural modification for achieving faster signaling of resonating peripheral tissues. The conserved projection patterns of COs suggest functional importance of the FCO and subgenual organ for vibrational communications.

  17. Structure determination by photoelectron diffraction of small molecules on surfaces

    International Nuclear Information System (INIS)

    Booth, N.A.

    1998-05-01

    The synchrotron radiation based technique of Photoelectron Diffraction (PhD) has been applied to three adsorption systems. Structure determinations, are presented for each system which involve the adsorption of small molecules on the low index {110} plane of single crystal Cu and Ni substrates. For the NH 3 -Cu(110) system PhD was successful in determining a N-Cu bondlength of 2.05 ± 0.03 A as well as values for the anisotropic vibrational amplitudes of the N and an expansion of the 1st to 2nd Cu substrate layer spacing from the bulk value of 0.08 ± 0.08 A. The most significant and surprising structural parameter determined for this system was that the N atom occupies an asymmetric adsorption site. Rather than being situated in the expected high symmetry atop site the N atom was found to be offset parallel to the surface by 0.37 ± 0.12 A in the [001] azimuth. In studying the glycine-Cu(110) system the adsorption structure of an amino-acid has been quantified. The local adsorption geometries of all the atoms involved in the molecule to surface bond have been determined. The glycine molecule is found to be bonded to the surface via both its amino and carboxylate functional groups. The molecule straddles two [11-bar0] rows of the Cu substrate. The two O atoms are found to be in identical sites both approximately atop Cu atoms on the [11-bar0] rows offset parallel to the surface by 0.80 ± 0.05 A in the [001] azimuth, the O-Cu bondlength was found to be 2.03 ± 0.05 A. The N atom was also found to adsorb in an approximately atop geometry but offset parallel to the surface by 0.24 ± 0.10A in the [11-bar0] direction, the N-Cu bondlength was found to be 2.05± 0.05 A. PhD was unsuccessful in determining the positions of the two C atoms that form a bridge between the two functional groups bonded to the surface due to difficulties in separating the two inequivalent contributions to the final intensity modulation function. For the CN-Ni(110) system both PhD and Near Edge

  18. Determination of Aflatoxin B1 Levels in Organic Spices and Herbs

    Science.gov (United States)

    Tosun, Halil; Arslan, Recep

    2013-01-01

    Organically produced spices and herbs were analyzed for determination of aflatoxin B1 (AFB1) by ELISA using immunoaffinity column. For this purpose 93 organic spices and 37 organic herbs were randomly selected from organic markets and organic shops in Turkey. AFB1 was detected in 58 organic spice and 32 organic herb samples. Among organic spice samples, the maximum value was detected in cinnamon sample (53 μg/kg). AFB1 was not detected in thyme samples. AFB1 levels of 41 organic spice samples were above the EU regulatory limit (5 μg/kg). Among organic herb samples the highest concentration of AFB1 (52.5 μg/kg) was detected in a rosehip sample. AFB1 levels of 21 organic herb samples were above the regulatory limits of the European Union. These results showed that more stringent measures must be taken for the prevention of mold contamination in the production of organic spices and herbs. PMID:23766719

  19. The Structural-functional Organization of the Urban Landschaft

    Directory of Open Access Journals (Sweden)

    Vasile GUŢULEAC

    2008-09-01

    Full Text Available The structure of the anthropic landschaft characterizes its internal organization, the connections between its components and the natural-anthropic associations of an inferior degree.The anthropic layer is to be analyzed in analogy with the natural component of the landschaft, which includes architectural edifices, communications, the geological component,the anthropic vegetation, the barren heaps resulted from mining activities, etc. The parametres of the anthropic components of the landschaft are the free surface, the built surface, the heightof the buildings and the density.The different geographical elements are reconstituted on the basis of NTCs (National Territorial Complex, separated on subtypes according to their specific (NTC IV – functionallandschaft area, NTC III – human settlement, NTC II – technogene fenced-in district, NTC I– technogene lot. We emphasized the features of these organizational types after we had donemuch research in field and in laboratory. We managed to draw a landschaft – functional mapof Czernowitz town, with a scale of 1: 10 000. We managed to detect 125 types of anthropiccomplex of lanschaft.For the urban territory we proposed two types of classification for the landschaftsystems: 1. NTCs that existed before the intense industrial anthropization; 2. technohenenatural complexes. The map of the anthropic-landschaft complexes of the town can be used asa basis for the geo-chemical map and for some applicative maps, especially ecological ones.

  20. Current structure and organization for renal patient assistance in Italy.

    Science.gov (United States)

    Alloatti, Sandro; Strippoli, Giovanni Fm; Buccianti, Gherardo; Daidone, Giuseppe; Schena, Francesco P

    2008-04-01

    Given the public health challenge and burden of chronic kidney disease, the Italian Society of Nephrology (SIN) has compiled a national census of Renal Units (RU) existing in the twenty Italian regions related to the year 2004. An on-line questionnaire including 158 items explored structural and human resources, organization aspects, activities and epidemiological data in SIN, 2004. The census identified 363 public RU, 303 satellite Dialysis Centres (DC) and 295 private DC totalling 961 DC [16.4 per million population (pmp)]. The inpatient renal beds were 2742 (47 pmp). Renal and dialysis activity was performed by 3728 physicians (64 pmp), of whom 2964 (80%) were nephrologists. There was no permanent medical assistance in 41% of satellite DC. There were 1802 renal admissions pmp and 99 renal biopsies pmp. The management of acute renal failure (13 456 cases; 230 pmp) represented a relevant proportion of the activities conducted in public RU. In 2004 there were 9858 new cases of end-stage kidney disease requiring renal replacement therapy (RRT) (169 pmp). On 31 December 2004, 60 058 patients were on RRT (1027 pmp), 43 293 of which (740 pmp) were on dialysis and 16 765 (287 pmp) with renal graft. This census of the Italian RU and DC in 2004 provides decision makers and healthcare stakeholders with detailed data for benchmarking and has financial implications for the public health system. Similar analyses may be conducted in other countries permitting standardization of medical and cost-related aspects of renal care.

  1. Marsh Soil Responses to Nutrients: Belowground Structural and Organic Properties.

    Science.gov (United States)

    Coastal marsh responses to nutrient enrichment apparently depend upon soil matrix and whether the system is primarily biogenic or minerogenic. Deteriorating organic rich marshes (Jamaica Bay, NY) receiving wastewater effluent had lower belowground biomass, organic matter, and soi...

  2. Production, purification, crystallization and structure determination of H-1 Parvovirus

    International Nuclear Information System (INIS)

    Halder, Sujata; Nam, Hyun-Joo; Govindasamy, Lakshmanan; Vogel, Michèle; Dinsart, Christiane; Salomé, Nathalie; McKenna, Robert; Agbandje-McKenna, Mavis

    2012-01-01

    The production, purification, crystallization and crystallographic analysis of H-1 Parvovirus, a gene-therapy vector, are reported. Crystals of H-1 Parvovirus (H-1PV), an antitumor gene-delivery vector, were obtained for DNA-containing capsids and diffracted X-rays to 2.7 Å resolution using synchrotron radiation. The crystals belonged to the monoclinic space group P2 1 , with unit-cell parameters a = 255.4, b = 350.4, c = 271.6 Å, β = 90.34°. The unit cell contained two capsids, with one capsid per crystallographic asymmetric unit. The H-1PV structure has been determined by molecular replacement and is currently being refined

  3. Structure of HIV-1 protease determined by neutron crystallography

    International Nuclear Information System (INIS)

    Adachi, Motoyasu; Kuroki, Ryota

    2009-01-01

    HIV-1 protease is an aspartic protease, and plays an essential role in replication of HIV. To develop HIV-1 protease inhibitors through structure-based drug design, it is necessary to understand the catalytic mechanism and inhibitor recognition of HIV-1 protease. We have determined the crystal structure of HIV-1 protease in complex with KNI-272 to 1.9 A resolution by neutron crystallography in combination with 1.4 A resolution X-ray diffraction data. The results show that the carbonyl group of hydroxymethylcarbonyl (HMC) in KNI-272 forms a hydrogen bonding interaction with protonated Asp 25 and the hydrogen atom from the hydroxyl group of HMC forms a hydrogen bonding interaction with the deprotonated Asp125. This is the first neutron report for HIV-1/inhibitor complex and shows directly the locations of key hydrogen atoms in catalysis and in the binding of a transition-state analog. The results confirm key aspect of the presumed catalytic mechanism of HIV-1 protease and will aid in the further development of protease inhibitors. (author)

  4. Determination of subsurface geological structure with borehole gravimetry

    International Nuclear Information System (INIS)

    Clark, S.R.; Hearst, J.R.

    1983-07-01

    Conventional gamma-gamma and gravimetric density measurements are routinely gathered for most holes used for underground nuclear tests. The logs serve to determine the subsurface structural geology near the borehole. The gamma-gamma density log measures density of the rock within about 15 cm of the borehole wall. The difference in gravity measured at two depths in a borehole can be interpreted in terms of the density of an infinite, homogeneous, horizontal bed between those depths. When the gravimetric density matches the gamma-gamma density over a given interval it is assumed that the bed actualy exists, and that rocks far from the hole must be the same as those encountered adjacent to the borehole. Conversely, when the gravimetric density differs from the gamma-gamma density it is apparent that the gravimeter is being influenced by a rock mass of different density than that at the hole wall. This mismatch can be a powerful tool to deduce the local structural geology. The geology deduced from gravity mesurements in emplacement hole, U4al, and the associated exploratory hole, UE4al, is an excellent example of the power of the method

  5. Determination of scattering structures from spatial coherence measurements.

    Science.gov (United States)

    Zarubin, A M

    1996-03-01

    A new method of structure determination and microscopic imaging with short-wavelength radiations (charged particles, X-rays, neutrons), based on measurements of the modulus and the phase of the degree of spatial coherence of the scattered radiation, is developed. The underlying principle of the method--transfer of structural information about the scattering potential via spatial coherence of the secondary (scattering) source of radiation formed by this potential--is expressed by the generalization of the van Cittert-Zernike theorem to wave and particle scattering [A.M. Zarubin, Opt. Commun. 100 (1993) 491; Opt. Commun. 102 (1993) 543]. Shearing interferometric techniques are proposed for implementing the above measurements; the limits of spatial resolution attainable by reconstruction of the absolute square of a 3D scattering potential and its 2D projections from the measurements are analyzed. It is shown theoretically that 3D imaging with atomic resolution can be realized in a "synthetic aperture" electron or ion microscope and that a 3D resolution of about 6 nm can be obtained with a "synthetic aperture" X-ray microscope. A proof-of-principle optical experiment is presented.

  6. A Determination of the Neutron Spin Structure Function

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Emlyn W

    2003-08-18

    The authors report the results of the experiment E142 which measured the spin dependent structure function of the neutron, g{sub 1}{sup n}(x, Q{sup 2}). The experiment was carried out at the Stanford Linear Accelerator Center by measuring an asymmetry in the deep inelastic scattering of polarized electrons from a polarized {sup 3}He target, at electron energies from 19 to 26 GeV. The structure function was determined over the kinematic range 0.03 < BJorken x < 0.6 and 1.0 < Q{sup 2} < 5.5 (GeV/c){sup 2}. An evaluation of the integral {integral}{sub 0}{sup 1} g{sub 1}{sup n}(x,Q{sup 2})dx at fixed Q{sup 2} = 2 (GeV/c){sup 2} yields the final result {Lambda}{sub 1}{sup n} = -0.032 {+-} 0.006 (stat.) {+-} 0.009 (syst.). This result, when combined with the integral of the proton spin structure function measured in other experiments, confirms the fundamental Bjorken sum rule with O({alpha}{sub s}{sup 3}) corrections to within one standard deviation. This is a major success for perturbative Quantum Chromodynamics. Some ancillary results include the findings that the Ellis-Jaffe sum rule for the neutron is violated at the 2 {sigma} level, and that the total contribution of the quarks to the helicity of the nucleon is 0.36 {+-} 0.10. The strange sea polarization is estimated to be small and negative, {Delta}s = -0.07 {+-} 0.04.

  7. Strategy, Corporate Culture, Structure and Operational Processes as the Context for the Innovativeness of an Organization

    Directory of Open Access Journals (Sweden)

    Szczepańska-Woszczyna Katarzyna

    2018-03-01

    Full Text Available The paper refers to relationships between the innovativeness of an organization and its selected determinants such as strategy, corporate culture, structure and operational processes. Research was conducted among 200 managers at the top, middle and operational levels of management (200 companies operating in Poland implementing innovations - innovative companies. Conditions leading to innovations are described as the combination of processes, which result from the internal and external dynamics of a given entity. The analysis assumed that the assessment of company innovativeness would be based on an assessment of whether the company is a leader in the industry in terms of new products (the higher the rating, the more innovative the company is considered to be. The relationship between the dimensions of the company's functioning and the degree of its innovativeness was rated on the basis of two measures: the Spearman's rank correlation coefficient and the chi-square coefficient. It was assumed that the most innovative companies have structures similar to organic ones, with a weak influence of the elements of mechanistic structures. This assumption was proven in relation to features of organizations considered important for innovativeness.

  8. The application of mass and energy conservation laws in physiologically structured population models of heterotrophic organisms

    Science.gov (United States)

    Kooijman; Kooi; Hallam

    1999-04-07

    Rules for energy uptake, and subsequent utilization, form the basis of population dynamics and, therefore, explain the dynamics of the ecosystem structure in terms of changes in standing crops and size distributions of individuals. Mass fluxes are concomitant with energy flows and delineate functional aspects of ecosystems by defining the roles of individuals and populations. The assumption of homeostasis of body components, and an assumption about the general structure of energy budgets, imply that mass fluxes can be written as weighted sums of three organizing energy fluxes with the weight coefficients determined by the conservation law of mass. These energy fluxes are assimilation, maintenance and growth, and provide a theoretical underpinning of the widely applied empirical method of indirect calorimetry, which relates dissipating heat linearly to three mass fluxes: carbon dioxide production, oxygen consumption and N-waste production. A generic approach to the stoichiometry of population energetics from the perspective of the individual organism is proposed and illustrated for heterotrophic organisms. This approach indicates that mass transformations can be identified by accounting for maintenance requirements and overhead costs for the various metabolic processes at the population level. The theoretical background for coupling the dynamics of the structure of communities to nutrient cycles, including the water balance, as well as explicit expressions for the dissipating heat at the population level are obtained based on the conservation law of energy. Specifications of the general theory employ the Dynamic Energy Budget model for individuals. Copyright 1999 Academic Press.

  9. Determination and analysis of dispersive optical constants of some organic thin films

    International Nuclear Information System (INIS)

    Kaya, Y.; Taysioglu, A. A.; Peksoez, A.; Irez, G.; Derebasi, N.; Kaynak, G.

    2010-01-01

    Schiff bases are an important class of ligands in coordination chemistry and find extensive application in different fields. Recently, increased interest in organic thin film materials has arisen due to their extensive applications in the fields of mechanics, flexible electronics and optics. Optoelectronics is the area in which organic films and organic-inorganic nanostructures have found their main applications in the last decade. These organic thin films have been also used in a wide variety of applications such as Schottky diodes, solid state devices and optical sensors. The optical constants (refractive index, n; extinction coefficient, k and dielectric constant, e) of some organic thin films were determined using reflectance and transmittance spectra. Analysis of the basis absorption spectra was also carried out to determine optical band gap (Eg) and Urbach parameter (E0). A surface observation of these thin films was also carried out by an Atomic Force Microscope.

  10. Emission Characteristics of Organic Light-Emitting Diodes and Organic Thin-Films with Planar and Corrugated Structures

    Directory of Open Access Journals (Sweden)

    Mao-Kuo Wei

    2010-04-01

    Full Text Available In this paper, we review the emission characteristics from organic light-emitting diodes (OLEDs and organic molecular thin films with planar and corrugated structures. In a planar thin film structure, light emission from OLEDs was strongly influenced by the interference effect. With suitable design of microcavity structure and layer thicknesses adjustment, optical characteristics can be engineered to achieve high optical intensity, suitable emission wavelength, and broad viewing angles. To increase the extraction efficiency from OLEDs and organic thin-films, corrugated structure with micro- and nano-scale were applied. Microstructures can effectively redirects the waveguiding light in the substrate outside the device. For nanostructures, it is also possible to couple out the organic and plasmonic modes, not only the substrate mode.

  11. Deep transcriptome sequencing provides new insights into the structural and functional organization of the wheat genome.

    Science.gov (United States)

    Pingault, Lise; Choulet, Frédéric; Alberti, Adriana; Glover, Natasha; Wincker, Patrick; Feuillet, Catherine; Paux, Etienne

    2015-02-10

    Because of its size, allohexaploid nature, and high repeat content, the bread wheat genome is a good model to study the impact of the genome structure on gene organization, function, and regulation. However, because of the lack of a reference genome sequence, such studies have long been hampered and our knowledge of the wheat gene space is still limited. The access to the reference sequence of the wheat chromosome 3B provided us with an opportunity to study the wheat transcriptome and its relationships to genome and gene structure at a level that has never been reached before. By combining this sequence with RNA-seq data, we construct a fine transcriptome map of the chromosome 3B. More than 8,800 transcription sites are identified, that are distributed throughout the entire chromosome. Expression level, expression breadth, alternative splicing as well as several structural features of genes, including transcript length, number of exons, and cumulative intron length are investigated. Our analysis reveals a non-monotonic relationship between gene expression and structure and leads to the hypothesis that gene structure is determined by its function, whereas gene expression is subject to energetic cost. Moreover, we observe a recombination-based partitioning at the gene structure and function level. Our analysis provides new insights into the relationships between gene and genome structure and function. It reveals mechanisms conserved with other plant species as well as superimposed evolutionary forces that shaped the wheat gene space, likely participating in wheat adaptation.

  12. Structure transformations of endocrine system organs during adaptation to increased radioactivity

    International Nuclear Information System (INIS)

    Ermakova, O.V.

    2004-01-01

    It is well known that during ecological monitoring of contaminated territories registration of early abnormalities in an organism is hampered by man-caused influence of habitat. Under these circumstances study of both structural and functional changes in organs and tissues of rodents inhabiting radioactive contaminated territories is of great importance. Study of structural features of endocrine glands, hormones of which trigger the process of active adaptive changes in an organism, is very important in radioecological surveys. Basing on long-term study of voles we have determined that long-term living by rodents on the territories characterized by increased natural and artificial radioactivity (radium contaminated fields in the Komi Republic and 30-km zone of Chernobyl APS) substantially influences morpho-functional state of endocrine system organs, causing quantitative and qualitative changes. It is demonstrated that population processes modify biological consequences of small doze chronic ionizing radiation in habitat. We noticed the following: high heterogeneity of histological changes of thyroid gland and adrenal gland as a response to radioactive habitat contamination; disorder of interconnection among different links of endocrine system; dependence of radiation effects on gender, age, degree and character of radiation contamination of a habitat as well as duration of radioactive influence. We have got data on morphological characteristics of thyroid gland and adrenal gland during different phases of population amount of this kind of rodents. It was discovered that effectiveness of radiation influence is not the same during different periods of population cycle. Presence of voles on the territories characterized by increased radioactivity causes chronic tension of adrenal cortex (increasing of the organ mass, enlarging of thickness of zona fasciculata and zona reticularis). Destructive-necrotic processes combine with manifestation of reparative regeneration

  13. Time trends in organ donation after neurologic determination of death: a cohort study

    Science.gov (United States)

    Kramer, Andreas H.; Baht, Ryan; Doig, Christopher J.

    2017-01-01

    Background: The cause of brain injury may influence the number of organs that can be procured and transplanted with donation following neurologic determination of death. We investigated whether the distribution of causes responsible for neurologic death has changed over time and, if so, whether this has had an impact on organ quality, transplantation rates and recipient outcomes. Methods: We performed a cohort study involving consecutive brain-dead organ donors in southern Alberta between 2003 and 2014. For each donor, we determined last available measures of organ injury and number of organs transplanted, and compared these variables for various causes of neurologic death. We compared trends to national Canadian data for 2000-2013 (2000-2011 for Quebec). Results: There were 226 brain-dead organ donors over the study period, of whom 100 (44.2%) had anoxic brain injury, 63 (27.9%) had stroke, and 51 (22.6%) had traumatic brain injury. The relative proportion of donors with traumatic brain injury decreased over time (> 30% in 2003-2005 v. 6%-23% in 2012-2014) (p = 0.004), whereas that with anoxic brain injury increased (14%-37% v. 46%-80%, respectively) (p organs transplanted per donor was 3.6 with anoxic brain injury versus 4.5 with traumatic brain injury or stroke (p = 0.002). Interpretation: Anoxic brain injury has become a leading cause of organ donation after neurologic determination of death in Canada. Organs from donors with anoxic brain injury have a greater degree of injury, and fewer are transplanted. These findings have implications for availability of organs for transplantation in patients with end-stage organ failure. PMID:28401114

  14. Structural determinants of phenotypic diversity and replication rate of human prions.

    Directory of Open Access Journals (Sweden)

    Jiri G Safar

    2015-04-01

    Full Text Available The infectious pathogen responsible for prion diseases is the misfolded, aggregated form of the prion protein, PrPSc. In contrast to recent progress in studies of laboratory rodent-adapted prions, current understanding of the molecular basis of human prion diseases and, especially, their vast phenotypic diversity is very limited. Here, we have purified proteinase resistant PrPSc aggregates from two major phenotypes of sporadic Creutzfeldt-Jakob disease (sCJD, determined their conformational stability and replication tempo in vitro, as well as characterized structural organization using recently emerged approaches based on hydrogen/deuterium (H/D exchange coupled with mass spectrometry. Our data clearly demonstrate that these phenotypically distant prions differ in a major way with regard to their structural organization, both at the level of the polypeptide backbone (as indicated by backbone amide H/D exchange data as well as the quaternary packing arrangements (as indicated by H/D exchange kinetics for histidine side chains. Furthermore, these data indicate that, in contrast to previous observations on yeast and some murine prion strains, the replication rate of sCJD prions is primarily determined not by conformational stability but by specific structural features that control the growth rate of prion protein aggregates.

  15. Structure of health-care dyad leadership: an organization's experience.

    Science.gov (United States)

    Saxena, Anurag; Davies, Maura; Philippon, Don

    2018-05-08

    Purpose This study aims to explore the structural aspects (roles, responsibilities and reporting) of dyad leadership in one health-care organization (HCO). Design/methodology/approach The perceptions of 32 leaders (17 physician leaders and 15 dyad co-leaders) in formal leadership positions (six first-level with formal authority limited to teams or divisions, 23 middle-level with wider departmental or program responsibility and three senior-level with institution-wide authority) were obtained through focus groups and surveys. In addition, five senior leaders were interviewed. Descriptive statistics was used for quantitative data, and qualitative data were analyzed for themes by coding and categorization. Findings There are a large number of shared responsibilities in the hybrid model, as most activities in HCOs bridge administrative and professional spheres. These span the leadership (e.g. global performance and quality improvement) and management (e.g. human resources, budgets and education delivery) domains. The individual responsibilities, except for staff and physician engagement are in the management domain (e.g. operations and patient care). Both partners are responsible for joint decision-making, projecting a united front and joint reporting through a quadrat format. The mutual relationship and joint accountability are key characteristics and are critical to addressing potential conflicts and contradictions and achieving coherence. Practical implications Clarity of role will assist development of standardized job descriptions and required competencies, recruitment and leadership development. Originality/value This is an original empirical study presenting an integrated view of dyad leaders and senior leadership, meaningful expansion of shared responsibilities including academic functions and developing mutual relationship and emphasizing the central role of stability generating management functions.

  16. The Formal Organization of Knowledge: An Analysis of Academic Structure.

    Science.gov (United States)

    Gumport, Patricia J.; Snydman, Stuart K.

    2002-01-01

    A case study of San Jose State University examined how changes in what counts as knowledge are reflected in universities' academic structure. Found that the multidimensionality of academic structure, with bureaucratic (departmental) structure relatively fixed and programmatic (degree program) structure relatively open, enables universities to…

  17. Structural Determinants and Children's Oral Health: A Cross-National Study.

    Science.gov (United States)

    Baker, S R; Foster Page, L; Thomson, W M; Broomhead, T; Bekes, K; Benson, P E; Aguilar-Diaz, F; Do, L; Hirsch, C; Marshman, Z; McGrath, C; Mohamed, A; Robinson, P G; Traebert, J; Turton, B; Gibson, B J

    2018-03-01

    Much research on children's oral health has focused on proximal determinants at the expense of distal (upstream) factors. Yet, such upstream factors-the so-called structural determinants of health-play a crucial role. Children's lives, and in turn their health, are shaped by politics, economic forces, and social and public policies. The aim of this study was to examine the relationship between children's clinical (number of decayed, missing, and filled teeth) and self-reported oral health (oral health-related quality of life) and 4 key structural determinants (governance, macroeconomic policy, public policy, and social policy) as outlined in the World Health Organization's Commission for Social Determinants of Health framework. Secondary data analyses were carried out using subnational epidemiological samples of 8- to 15-y-olds in 11 countries ( N = 6,648): Australia (372), New Zealand (three samples; 352, 202, 429), Brunei (423), Cambodia (423), Hong Kong (542), Malaysia (439), Thailand (261, 506), United Kingdom (88, 374), Germany (1498), Mexico (335), and Brazil (404). The results indicated that the type of political regime, amount of governance (e.g., rule of law, accountability), gross domestic product per capita, employment ratio, income inequality, type of welfare regime, human development index, government expenditure on health, and out-of-pocket (private) health expenditure by citizens were all associated with children's oral health. The structural determinants accounted for between 5% and 21% of the variance in children's oral health quality-of-life scores. These findings bring attention to the upstream or structural determinants as an understudied area but one that could reap huge rewards for public health dentistry research and the oral health inequalities policy agenda.

  18. Determination of the structural phase and octahedral rotation angle in halide perovskites

    Science.gov (United States)

    dos Reis, Roberto; Yang, Hao; Ophus, Colin; Ercius, Peter; Bizarri, Gregory; Perrodin, Didier; Shalapska, Tetiana; Bourret, Edith; Ciston, Jim; Dahmen, Ulrich

    2018-02-01

    A key to the unique combination of electronic and optical properties in halide perovskite materials lies in their rich structural complexity. However, their radiation sensitive nature limits nanoscale structural characterization requiring dose efficient microscopic techniques in order to determine their structures precisely. In this work, we determine the space-group and directly image the Br halide sites of CsPbBr3, a promising material for optoelectronic applications. Based on the symmetry of high-order Laue zone reflections of convergent-beam electron diffraction, we identify the tetragonal (I4/mcm) structural phase of CsPbBr3 at cryogenic temperature. Electron ptychography provides a highly sensitive phase contrast measurement of the halide positions under low electron-dose conditions, enabling imaging of the elongated Br sites originating from the out-of-phase octahedral rotation viewed along the [001] direction of I4/mcm persisting at room temperature. The measurement of these features and comparison with simulations yield an octahedral rotation angle of 6.5°(±1.5°). The approach demonstrated here opens up opportunities for understanding the atomic scale structural phenomena applying advanced characterization tools on a wide range of radiation sensitive halide-based all-inorganic and hybrid organic-inorganic perovskites.

  19. The electro-structural behaviour of yarn-like carbon nanotube fibres immersed in organic liquids

    International Nuclear Information System (INIS)

    Terrones, Jeronimo; Windle, Alan H; Elliott, James A

    2014-01-01

    Yarn-like carbon nanotube (CNT) fibres are a hierarchically-structured material with a variety of promising applications such as high performance composites, sensors and actuators, smart textiles, and energy storage and transmission. However, in order to fully realize these possibilities, a more detailed understanding of their interactions with the environment is required. In this work, we describe a simplified representation of the hierarchical structure of the fibres from which several mathematical models are constructed to explain electro-structural interactions of fibres with organic liquids. A balance between the elastic and surface energies of the CNT bundle network in different media allows the determination of the maximum lengths that open junctions can sustain before collapsing to minimize the surface energy. This characteristic length correlates well with the increase of fibre resistance upon immersion in organic liquids. We also study the effect of charge accumulation in open interbundle junctions and derive expressions to describe experimental data on the non-ohmic electrical behaviour of fibres immersed in polar liquids. Our analyses suggest that the non-ohmic behaviour is caused by progressively shorter junctions collapsing as the voltage is increased. Since our models are not based on any property unique to carbon nanotubes, they should also be useful to describe other hierarchical structures. (paper)

  20. Self-organized structures in a superorganism: do ants “behave” like molecules?

    Science.gov (United States)

    Detrain, Claire; Deneubourg, Jean-Louis

    2006-09-01

    While the striking structures (e.g. nest architecture, trail networks) of insect societies may seem familiar to many of us, the understanding of pattern formation still constitutes a challenging problem. Over the last two decades, self-organization has dramatically changed our view on how collective decision-making and structures may emerge out of a population of ant workers having each their own individuality as well as a limited access to information. A variety of collective behaviour spontaneously outcome from multiple interactions between nestmates, even when there is no directing influence imposed by an external template, a pacemaker or a leader. By focussing this review on foraging structures, we show that ant societies display some properties which are usually considered in physico-chemical systems, as typical signatures of self-organization. We detail the key role played by feed-back loops, fluctuations, number of interacting units and sensitivity to environmental factors in the emergence of a structured collective behaviour. Nonetheless, going beyond simple analogies with non-living self-organized patterns, we stress on the specificities of social structures made of complex living units of which the biological features have been selected throughout the evolution depending on their adaptive value. In particular, we consider the ability of each ant individual to process information about environmental and social parameters, to accordingly tune its interactions with nestmates and ultimately to determine the final pattern emerging at the collective level. We emphasize on the parsimony and simplicity of behavioural rules at the individual level which allow an efficient processing of information, energy and matter within the whole colony.

  1. Proton surface charge determination in Spodosol horizons with organically bound aluminum

    Science.gov (United States)

    Skyllberg, Ulf; Borggaard, Ole K.

    1998-05-01

    Net proton surface charge densities were determined in O, E, Bh, and Bs horizons of a sandy till, Spodosol from Denmark, by means of acid-base titration combined with ion adsorption in 0.005 M Ca(NO 3) 2 and independent permanent charge determination. The release of organic anions exceeded the adsorption of NO 3-, resulting in a desorption of anions in all horizons. Data were found to obey the law of balance between surface charges and adsorbed ions only when charges pertaining to Al and organic anions released during the titration experiments were accounted for, in addition to charges pertaining the potential determining ions (PDI) H + and OH - and the index ions Ca 2+ and NO 3-. It was furthermore shown that the point of zero net proton charge (PZNPC) in soils highly depends on the concentration of organically bound Al. Approaches previously used in soils, in which adsorbed Al n+ has been ignored (i.e., considered equivalent to nH + as a PDI), resulted in a PZNPC of 4.1 in the Bs horizon. If instead organically bound Al was accounted for as a counter-ion similar to 3/2Ca 2+, a PZNPC of 2.9 was obtained for the same Bs horizon. Based on PZNPC values estimated by the latter approach, combined with a weak-acid analog, it was shown that organic proton surface charges buffered pH with a similar intensity in the O, E, Bh, and Bs horizons of this study. Because the acidity of Al adsorbed to conjugate bases of soil organic acids is substantially weaker than the acidity of the corresponding protonated form of the organic acids, the point of zero net proton charge (PZNPC) will increase if the concentration of organically adsorbed Al increases at the expense of adsorbed H. This means that PZNPC values determined for soils with unknown concentrations of organically adsorbed Al are highly operational and not very meaningful as references.

  2. Modelling the Impact of Organization Structure and Whistle Blowers on Intra-Organizational Corruption Contagion

    OpenAIRE

    Nekovee, Maziar; Pinto, Jonathan

    2017-01-01

    We complement the rich conceptual work on organizational corruption by quantitatively modelling the spread of corruption within organizations. We systematically vary four organizational culture-related parameters, i.e., organization structure, location of bad apple, employees propensity to become corrupted (corruption probability), and number of whistle-blowers. Our simulation studies find that in organizations with flatter structures, corruption permeates the organization at a lower threshol...

  3. Determination of the orbital lineup at reactive organic semiconductor interfaces using photoemission spectroscopy

    International Nuclear Information System (INIS)

    Schlaf, R.; Merritt, C. D.; Picciolo, L. C.; Kafafi, Z. H.

    2001-01-01

    We determined the orbital lineup of the tris (8-hydroxyquinolinato) gallium (Gaq 3 )/Mg interface using combined x-ray and ultraviolet photoemission spectroscopy (XPS and UPS) measurements. The Gaq 3 /Mg system is a prototypical model structure for organic electron/low work function electrode transporting materials interfaces found in organic light emitting diodes (OLED). A Gaq 3 thin film was grown in 15 steps on a previously sputter-cleaned Mg substrate starting at a 1 Aa nominal thickness up to a final thickness of 512 Aa. Before, and in between the growth steps, the sample surface was characterized by XPS and UPS. The results indicate the formation of a reaction layer of about 12 Aa thickness at the Mg interface, which resulted in a 0.96 V interface dipole potential. At Gaq 3 coverages higher than 256 Aa, a strong charging shift occurred in the overlayer related UPS-emission lines, which was identified by measuring the high binding energy cutoff (secondary edge) of both the XP and UP spectra. The several magnitudes different x-ray and ultraviolet source photon intensities allow pinpointing charging shifts with high sensitivity. Due to the low work function of the reacted interface layer, the Gaq 3 electronic states are aligned at a binding energy below the substrate Fermi edge that exceeds the magnitude of the optical gap between the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO). This allowed the conclusion that the ground state exciton binding energy of Gaq 3 needs to be larger than 0.43 eV. Based on these considerations, the lowest possible electron injection barrier matching the experimental data was estimated to be 0.15 eV. copyright 2001 American Institute of Physics

  4. Cryo-EM structure of human adenovirus D26 reveals the conservation of structural organization among human adenoviruses.

    Science.gov (United States)

    Yu, Xiaodi; Veesler, David; Campbell, Melody G; Barry, Mary E; Asturias, Francisco J; Barry, Michael A; Reddy, Vijay S

    2017-05-01

    Human adenoviruses (HAdVs) cause acute respiratory, ocular, and gastroenteric diseases and are also frequently used as gene and vaccine delivery vectors. Unlike the archetype human adenovirus C5 (HAdV-C5), human adenovirus D26 (HAdV-D26) belongs to species-D HAdVs, which target different cellular receptors, and is differentially recognized by immune surveillance mechanisms. HAdV-D26 is being championed as a lower seroprevalent vaccine and oncolytic vector in preclinical and human clinical studies. To understand the molecular basis for their distinct biological properties and independently validate the structures of minor proteins, we determined the first structure of species-D HAdV at 3.7 Å resolution by cryo-electron microscopy. All the hexon hypervariable regions (HVRs), including HVR1, have been identified and exhibit a distinct organization compared to those of HAdV-C5. Despite the differences in the arrangement of helices in the coiled-coil structures, protein IX molecules form a continuous hexagonal network on the capsid exterior. In addition to the structurally conserved region (3 to 300) of IIIa, we identified an extra helical domain comprising residues 314 to 390 that further stabilizes the vertex region. Multiple (two to three) copies of the cleaved amino-terminal fragment of protein VI (pVIn) are observed in each hexon cavity, suggesting that there could be ≥480 copies of VI present in HAdV-D26. In addition, a localized asymmetric reconstruction of the vertex region provides new details of the three-pronged "claw hold" of the trimeric fiber and its interactions with the penton base. These observations resolve the previous conflicting assignments of the minor proteins and suggest the likely conservation of their organization across different HAdVs.

  5. Perceptual Organization of Visual Structure Requires a Flexible Learning Mechanism

    Science.gov (United States)

    Aslin, Richard N.

    2011-01-01

    Bhatt and Quinn (2011) provide a compelling and comprehensive review of empirical evidence that supports the operation of principles of perceptual organization in young infants. They also have provided a comprehensive list of experiences that could serve to trigger the learning of at least some of these principles of perceptual organization, and…

  6. THE EXTENT OF CLONAL STRUCTURE IN DIFFERENT LYMPHOID ORGANS

    NARCIS (Netherlands)

    HERMANS, MHA; WUBBENA, A; KROESE, FGM; HUNT, SV; COWAN, R; OPSTELTEN, D

    1992-01-01

    To gain insight into the clonal organization of lymphoid organs, we studied the distribution in situ of donor-derived cells in near-physiological chimeras. We introduced RT7b fetal liver cells into nonirradiated congenic RT7a neonatal rats. The chimerism 6-20 wk after injection ranged from 0.3 to

  7. Challenges of Control in Functional Organization Structures: Example of Outsourcing Sector

    OpenAIRE

    Agnieszka Maciejczyk

    2016-01-01

    Effective control of an organization is strictly connected with its organization structure. When a company decides to outsource a part of its operations, a new structure is applied. Also, the system of control should be reviewed and adjusted to the new model of business in order to be effective. Usually, the outsourcing companies apply functional organization structure which is the most common way of grouping business activities. The goal of the paper was to point challenges and aspects which...

  8. Structural Determinants of Autoproteolysis of the Haemophilus influenzae Hap Autotransporter▿

    Science.gov (United States)

    Kenjale, Roma; Meng, Guoyu; Fink, Doran L.; Juehne, Twyla; Ohashi, Tomoo; Erickson, Harold P.; Waksman, Gabriel; St. Geme, Joseph W.

    2009-01-01

    Haemophilus influenzae is a gram-negative bacterium that initiates infection by colonizing the upper respiratory tract. The H. influenzae Hap autotransporter protein mediates adherence, invasion, and microcolony formation in assays with respiratory epithelial cells and presumably facilitates colonization. The serine protease activity of Hap is associated with autoproteolytic cleavage and extracellular release of the HapS passenger domain, leaving the Hapβ C-terminal domain embedded in the outer membrane. Cleavage occurs most efficiently at the LN1036-37 peptide bond and to a lesser extent at three other sites. In this study, we utilized site-directed mutagenesis, homology modeling, and assays with a peptide library to characterize the structural determinants of Hap proteolytic activity and cleavage specificity. In addition, we used homology modeling to predict the S1, S2, and S4 subsite residues of the Hap substrate groove. Our results indicate that the P1 and P2 positions at the Hap cleavage sites are critical for cleavage, with leucine preferred over larger hydrophobic residues or other amino acids in these positions. The substrate groove is formed by L263 and N274 at the S1 subsite, R264 at the S2 subsite, and E265 at the S4 subsite. This information may facilitate design of approaches to block Hap activity and interfere with H. influenzae colonization. PMID:19687208

  9. Integrated corporate structure life cycle management modeling and organization

    OpenAIRE

    Naumenko, M.; Morozova, L.

    2011-01-01

    Integrated business structure presented as complementary pool of its participants skills. The methodical approach to integrated business structure life cycle modeling proposed. Recommendations of enterprises life cycles stages correlate are submitted.

  10. Determination of uranyl nitrate diffusion coefficients in organic and aqueous media using the porous diaphragm method

    International Nuclear Information System (INIS)

    Chierice, G.O.

    1974-01-01

    The diffusion coefficient is one of the parameters necessary for the obtention of the extraction exponential coefficients, that are contained within the H.T.U. (height of transfer unity) calculation expression, when operating with continuous organic phase. The organic phase used was tri-n-butyl-phosphate (TBP) and varsol in the 35% and 65% proportions respectively. After each experiment, the uranium content present in each compartment was spectrophotometrically determined and the quantities contained in the aqueous phases were determined by means of volumetric titration. It was found out that the uranyl ion diffusion coefficient is two and one half times less in organic phase, this just being attributed to the greater interactions of the uranyl ions in organic than in aqueous medium

  11. Modeling the Structure and Effectiveness of Intelligence Organizations: Dynamic Information Flow Simulation

    National Research Council Canada - National Science Library

    Behrman, Robert; Carley, Kathleen

    2003-01-01

    This paper describes the Dynamic Information Flow Simulation (DIFS), an abstract model for analyzing the structure and function of intelligence support organizations and the activities of entities within...

  12. Targeting acetylcholinesterase: identification of chemical leads by high throughput screening, structure determination and molecular modeling.

    Directory of Open Access Journals (Sweden)

    Lotta Berg

    Full Text Available Acetylcholinesterase (AChE is an essential enzyme that terminates cholinergic transmission by rapid hydrolysis of the neurotransmitter acetylcholine. Compounds inhibiting this enzyme can be used (inter alia to treat cholinergic deficiencies (e.g. in Alzheimer's disease, but may also act as dangerous toxins (e.g. nerve agents such as sarin. Treatment of nerve agent poisoning involves use of antidotes, small molecules capable of reactivating AChE. We have screened a collection of organic molecules to assess their ability to inhibit the enzymatic activity of AChE, aiming to find lead compounds for further optimization leading to drugs with increased efficacy and/or decreased side effects. 124 inhibitors were discovered, with considerable chemical diversity regarding size, polarity, flexibility and charge distribution. An extensive structure determination campaign resulted in a set of crystal structures of protein-ligand complexes. Overall, the ligands have substantial interactions with the peripheral anionic site of AChE, and the majority form additional interactions with the catalytic site (CAS. Reproduction of the bioactive conformation of six of the ligands using molecular docking simulations required modification of the default parameter settings of the docking software. The results show that docking-assisted structure-based design of AChE inhibitors is challenging and requires crystallographic support to obtain reliable results, at least with currently available software. The complex formed between C5685 and Mus musculus AChE (C5685•mAChE is a representative structure for the general binding mode of the determined structures. The CAS binding part of C5685 could not be structurally determined due to a disordered electron density map and the developed docking protocol was used to predict the binding modes of this part of the molecule. We believe that chemical modifications of our discovered inhibitors, biochemical and biophysical

  13. Influence of sample composition on aerosol organic and black carbon determinations

    Energy Technology Data Exchange (ETDEWEB)

    Novakov, T.; Corrigan, C.E.

    1995-07-01

    In this paper we present results on characterization of filter-collected redwood (Sequoia sempevirens)-needle and eucalyptus smoke particles by thermal, optical, and solvent extraction methods. Our results demonstrate that organic and black carbon concentrations determined by thermal and optical methods are not only method dependent, but also critically influenced by the overall chemical composition of the samples. These conclusions are supported by the following: (1) the organic fraction of biomass smoke particles analyzed includes a component, ranging in concentration from about 6-20% of total carbon or from 16-30% of organic carbon, that is relatively non-volatile and has a combustion temperature close to that of black carbon; (2) presence of K or Na in biomass smoke samples lowers the combustion temperatures of this organic component and of black carbon, making their combustion properties indistinguishable; (3) about 20% of total organic material is nonvolatile when heated to 550{degrees}C in an inert atmosphere. Consequently, thermal methods that rely on a specific temperature to separate organic from black carbon may either underestimate or overestimate the black and organic carbon concentrations, depending on the amounts of Na and K and on the composition and concentration of organic material present in a sample. These analytical uncertainties and, under some conditions, absorption by organic material may contribute to the variability of empirically derived proportionality between light transmission through filter deposits and black carbon concentrations.

  14. Influence of sample composition on aerosol organic and black carbon determinations

    International Nuclear Information System (INIS)

    Novakov, T.; Corrigan, C.E.

    1995-07-01

    In this paper we present results on characterization of filter-collected redwood (Sequoia sempevirens)-needle and eucalyptus smoke particles by thermal, optical, and solvent extraction methods. Our results demonstrate that organic and black carbon concentrations determined by thermal and optical methods are not only method dependent, but also critically influenced by the overall chemical composition of the samples. These conclusions are supported by the following: (1) the organic fraction of biomass smoke particles analyzed includes a component, ranging in concentration from about 6-20% of total carbon or from 16-30% of organic carbon, that is relatively non-volatile and has a combustion temperature close to that of black carbon; (2) presence of K or Na in biomass smoke samples lowers the combustion temperatures of this organic component and of black carbon, making their combustion properties indistinguishable; (3) about 20% of total organic material is nonvolatile when heated to 550 degrees C in an inert atmosphere. Consequently, thermal methods that rely on a specific temperature to separate organic from black carbon may either underestimate or overestimate the black and organic carbon concentrations, depending on the amounts of Na and K and on the composition and concentration of organic material present in a sample. These analytical uncertainties and, under some conditions, absorption by organic material may contribute to the variability of empirically derived proportionality between light transmission through filter deposits and black carbon concentrations

  15. Structure of bacterial communities in soil following cover crop and organic fertilizer incorporation.

    Science.gov (United States)

    Fernandez, Adria L; Sheaffer, Craig C; Wyse, Donald L; Staley, Christopher; Gould, Trevor J; Sadowsky, Michael J

    2016-11-01

    Incorporation of organic material into soils is an important element of organic farming practices that can affect the composition of the soil bacterial communities that carry out nutrient cycling and other functions crucial to crop health and growth. We conducted a field experiment to determine the effects of cover crops and fertilizers on bacterial community structure in agricultural soils under long-term organic management. Illumina sequencing of 16S rDNA revealed diverse communities comprising 45 bacterial phyla in corn rhizosphere and bulk field soil. Community structure was most affected by location and by the rhizosphere effect, followed by sampling time and amendment treatment. These effects were associated with soil physicochemical properties, including pH, moisture, organic matter, and nutrient levels. Treatment differences were apparent in bulk and rhizosphere soils at the time of peak corn growth in the season following cover crop and fertilizer application. Cover crop and fertilizer treatments tended to lower alpha diversity in early season samples. However, winter rye, oilseed radish, and buckwheat cover crop treatments increased alpha diversity in some later season samples compared to a no-amendment control. Fertilizer treatments and some cover crops decreased relative abundance of members of the ammonia-oxidizing family Nitrosomonadaceae. Pelleted poultry manure and Sustane® (a commercial fertilizer) decreased the relative abundance of Rhizobiales. Our data point to a need for future research exploring how (1) cover crops influence bacterial community structure and functions, (2) these effects differ with biomass composition and quantity, and (3) existing soil conditions and microbial community composition influence how soil microbial populations respond to agricultural management practices.

  16. Ion chromatographic determination of Di-n-butyl phosphate in degraded organic solvent

    International Nuclear Information System (INIS)

    Velavendan, P.; Pandey, N.K.; Kamachi Mudali, U.; Natarajan, R.

    2011-01-01

    In the present work a method for the determination of Di-n-butyl phosphate in organic streams using Ion Chromatography technique is developed and described here. The method involves the separation of Di-n-butyl phosphate (DBP) from 30% TBP-NPH (Tri-n-butylphosphate diluted in Normal Paraffin Hydrocarbon) and uranium/nitric acid matrix by an extraction of DBP in alkaline medium and subsequent ion-exchange separation in ion chromatography column followed by suppressed conductivity detection. Direct determination of DBP in lean/loaded organic solvent will lead to in accurate determination of DBP due to organic interference. DBP is quantified to lower limit of 1 ppm with 3% RSD. The results obtained with ion chromatographic technique are compared with those obtained by standard gas chromatographic technique. The developed method is much faster and total analysis can be completed within two hours. (author)

  17. Bio indicator organisms available to use for determination of radioactive elements in Turkey's seas

    International Nuclear Information System (INIS)

    Kocbas, F.; Guener, H.

    2006-01-01

    In determination of radioactive concentration and monitoring alive and lifeless environmental samples possess a significant place. Thus, intense study is carried out related to natural and artificial radionuclides sediment. Bio indicator living organisms inhabiting in sea ecosystems; are being evaluated in researches such as determinations of environmental pollution, natural and artificial radioactive elements. Turkey's seas are rich related to diversification of various types. In determining and monitoring radioactivity concentration widespread implementation of some sorts appeal attention and on the other hand inadequate usage of many types is observed. In the present study, providing information about the bio indicator organisms keep living in seas and plays important role in food supply chain and increasing the numbers of the types of organisms used are aimed

  18. Experimental determination of the empirical formula and energy content of unknown organics in waste streams

    Energy Technology Data Exchange (ETDEWEB)

    Shizas, I. [Univ. of Toronto, Dept. of Civil Engineering, Toronto, Ontario (Canada); Kosmatos, A. [Ontario Power Generation, Toronto, Ontario (Canada); Bagley, D.M. [Univ. of Toronto, Dept. of Civil Engineering, Toronto, Ontario (Canada)

    2002-06-15

    Two experimental methods are described in this paper: one for determining the empirical formula, and one for determining the energy content of unknown organics in waste streams. The empirical formula method requires volatile solids (VS), chemical oxygen demand (COD), total organic carbon (TOC), and total Kjeldahl nitrogen (TKN) to be measured for the waste; the formula can then be calculated from these values. To determine the energy content of the organic waste, bomb calorimetry was used with benzoic acid as a combustion aid. The results for standard compounds (glucose, propionic acid, L-arginine, and benzoic acid) were relatively good. The energy content measurement for wastewater and sludges had good reproducibility (i.e. 1.0 to 3.2% relative standard deviation for triplicate samples). Trouble encountered in the measurement of the empirical formulae of the waste samples was possibly due to difficulties with the TOC test; further analysis of this is required. (author)

  19. Experimental determination of the empirical formula and energy content of unknown organics in waste streams

    International Nuclear Information System (INIS)

    Shizas, I.; Kosmatos, A.; Bagley, D.M.

    2002-01-01

    Two experimental methods are described in this paper: one for determining the empirical formula, and one for determining the energy content of unknown organics in waste streams. The empirical formula method requires volatile solids (VS), chemical oxygen demand (COD), total organic carbon (TOC), and total Kjeldahl nitrogen (TKN) to be measured for the waste; the formula can then be calculated from these values. To determine the energy content of the organic waste, bomb calorimetry was used with benzoic acid as a combustion aid. The results for standard compounds (glucose, propionic acid, L-arginine, and benzoic acid) were relatively good. The energy content measurement for wastewater and sludges had good reproducibility (i.e. 1.0 to 3.2% relative standard deviation for triplicate samples). Trouble encountered in the measurement of the empirical formulae of the waste samples was possibly due to difficulties with the TOC test; further analysis of this is required. (author)

  20. Crystal Structure of the 30S Ribosomal Subunit from Thermus Thermophilus: Purification, Crystallization and Structure Determination

    International Nuclear Information System (INIS)

    Clemons, William M. Jr.; Brodersen, Ditlev E.; McCutcheonn, John P.; May, Joanna L.C.; Carter, Andrew P.; Morgan-Warren, Robert J.; Wimberly, Brian T.; Ramakrishnan, Venki

    2001-01-01

    We describe the crystallization and structure determination of the 30 S ribosomal subunit from Thermus thermophilus. Previous reports of crystals that diffracted to 10 (angstrom) resolution were used as a starting point to improve the quality of the diffraction. Eventually, ideas such as the addition of substrates or factors to eliminate conformational heterogeneity proved less important than attention to detail in yielding crystals that diffracted beyond 3 (angstrom) resolution. Despite improvements in technology and methodology in the last decade, the structure determination of the 30 S subunit presented some very challenging technical problems because of the size of the asymmetric unit, crystal variability and sensitivity to radiation damage. Some steps that were useful for determination of the atomic structure were: the use of anomalous scattering from the LIII edges of osmium and lutetium to obtain the necessary phasing signal; the use of tunable, third-generation synchrotron sources to obtain data of reasonable quality at high resolution; collection of derivative data precisely about a mirror plane to preserve small anomalous differences between Bijvoet mates despite extensive radiation damage and multi-crystal scaling; the pre-screening of crystals to ensure quality, isomorphism and the efficient use of scarce third-generation synchrotron time; pre-incubation of crystals in cobalt hexaammine to ensure isomorphism with other derivatives; and finally, the placement of proteins whose structures had been previously solved in isolation, in conjunction with biochemical data on protein-RNA interactions, to map out the architecture of the 30 S subunit prior to the construction of a detailed atomic-resolution model.

  1. Determinants of innovation within health care organizations: literature review and Delphi study.

    Science.gov (United States)

    Fleuren, Margot; Wiefferink, Karin; Paulussen, Theo

    2004-04-01

    When introducing innovations to health care, it is important to gain insight into determinants that may facilitate or impede the introduction, in order to design an appropriate strategy for introducing the innovation. To obtain an overview of determinants of innovations in health care organizations, we carried out a literature review and a Delphi study. The Delphi study was intended to achieve consensus among a group of implementation experts on determinants identified from the literature review. We searched 11 databases for articles published between 1990 and 2000. The keywords varied according to the specific database. We also searched for free text. Forty-four implementation experts (implementation researchers, programme managers, and implementation consultants/advisors) participated in the Delphi study. The following studies were selected: (i) studies describing innovation processes, and determinants thereof, in health care organizations; (ii) studies where the aim of the innovations was to change the behaviour of health professionals; (iii) studies where the health care organizations provided direct patient care; and (iv) studies where only empirical studies were included. Two researchers independently selected the abstracts and analysed the articles. The determinants were divided into four categories: characteristics of the environment, characteristics of the organization, characteristics of the user (health professional), and characteristics of the innovation. When analysing the determinants, a distinction was made between systematically designed and non-systematically designed studies. In a systematic study, a determinant analysis was performed and the innovation strategy was adapted to these determinants. Furthermore, the determinants were associated with the degree of implementation, and both users and non-users of the innovation were asked about possible determinants. In the Delphi study, consensus was defined as agreement among 75% of the experts on

  2. CCDC 1416891: Experimental Crystal Structure Determination : Methyl-triphenyl-germanium

    KAUST Repository

    Bernatowicz, Piotr; Shkurenko, Aleksander; Osior, Agnieszka; Kamieński, Bohdan; Szymański, Sławomir

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from

  3. The development of quantitative determination method of organic acids in complex poly herbal extraction

    Directory of Open Access Journals (Sweden)

    I. L. Dyachok

    2016-08-01

    Full Text Available Aim. The development of sensible, economical and expressive method of quantitative determination of organic acids in complex poly herbal extraction counted on izovaleric acid with the use of digital technologies. Materials and methods. Model complex poly herbal extraction of sedative action was chosen as a research object. Extraction is composed of these medical plants: Valeriana officinalis L., Crataégus, Melissa officinalis L., Hypericum, Mentha piperita L., Húmulus lúpulus, Viburnum. Based on chemical composition of plant components, we consider that main pharmacologically active compounds, which can be found in complex poly herbal extraction are: polyphenolic substances (flavonoids, which are contained in Crataégus, Viburnum, Hypericum, Mentha piperita L., Húmulus lúpulus; also organic acids, including izovaleric acid, which are contained in Valeriana officinalis L., Mentha piperita L., Melissa officinalis L., Viburnum; the aminoacid are contained in Valeriana officinalis L. For the determination of organic acids content in low concentration we applied instrumental method of analysis, namely conductometry titration which consisted in the dependences of water solution conductivity of complex poly herbal extraction on composition of organic acids. Result. The got analytical dependences, which describes tangent lines to the conductometry curve before and after the point of equivalence, allow to determine the volume of solution expended on titration and carry out procedure of quantitative determination of organic acids in the digital mode. Conclusion. The proposed method enables to determine the point of equivalence and carry out quantitative determination of organic acids counted on izovaleric acid with the use of digital technologies, that allows to computerize the method on the whole.

  4. The structure optimization design of the organic solar cells using the FDTD method

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jian [College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Wang Chengwei, E-mail: cwwang@nwnu.edu.c [College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Li Yan [College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Zhou Feng; Liu Weimin [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2010-04-15

    The finite-different time-domain method (FDTD) was used to optimize structure of organic solar cells based on the heterojunction of the substituted polythiophene polymer (PEOPT) and the C{sub 60} molecule. The absorption of the device in visible light range was determined, and the maximized average absorption is about 88% at the wavelength of 469 nm. The effects of the glass substrate thickness on the absorption and the distribution of the optical energy inside the device were investigated. Based on the important roles of the optical energy at PEOPT/C{sub 60} interface in the photocurrent efficiency, the device structure was optimized for the maximized photocurrent efficiency. The optimal C{sub 60} thickness 29 nm was obtained for the wavelength of 469 nm. Meantime, when the PEOPT thickness is the range of 80-130 nm, there are few effects on optical energy at PEOPT/C{sub 60} interface.

  5. ERC Safety and Hygiene Programs functional organization structure and mission statement

    International Nuclear Information System (INIS)

    Coleman, S.R.

    2000-01-01

    This document provides a description of the functions, structure, commitments, and goals of the Environmental Restoration Contractor Safety and Hygiene Program. The current structure of the ERC Safety and Hygiene organization is described herein

  6. Structure determination of an 11-subunit exosome in complex with RNA by molecular replacement

    International Nuclear Information System (INIS)

    Makino, Debora Lika; Conti, Elena

    2013-01-01

    The crystallographic steps towards the structure determination of a complete eukaryotic exosome complex bound to RNA are presented. Phasing of this 11-protein subunit complex was carried out via molecular replacement. The RNA exosome is an evolutionarily conserved multi-protein complex involved in the 3′ degradation of a variety of RNA transcripts. In the nucleus, the exosome participates in the maturation of structured RNAs, in the surveillance of pre-mRNAs and in the decay of a variety of noncoding transcripts. In the cytoplasm, the exosome degrades mRNAs in constitutive and regulated turnover pathways. Several structures of subcomplexes of eukaryotic exosomes or related prokaryotic exosome-like complexes are known, but how the complete assembly is organized to fulfil processive RNA degradation has been unclear. An atomic snapshot of a Saccharomyces cerevisiae 420 kDa exosome complex bound to an RNA substrate in the pre-cleavage state of a hydrolytic reaction has been determined. Here, the crystallographic steps towards the structural elucidation, which was carried out by molecular replacement, are presented

  7. Interactions of the Calcite {10.4} Surface with Organic Compounds: Structure and Behaviour at Mineral – Organic Interfaces

    DEFF Research Database (Denmark)

    Hakim, S. S.; Olsson, M. H. M.; Sørensen, H. O.

    2017-01-01

    The structure and the strength of organic compound adsorption on mineral surfaces are of interest for a number of industrial and environmental applications, oil recovery, CO2 storage and contamination remediation. Biomineralised calcite plays an essential role in the function of many organisms...... that control crystal growth with organic macromolecules. Carbonate rocks, composed almost exclusively of calcite, host drinking water aquifers and oil reservoirs. In this study, we examined the ordering behaviour of several organic compounds and the thickness of the adsorbed layers formed on calcite {10...... monolayers. The results of this work indicate that adhered organic compounds from the surrounding environment can affect the surface behaviour, depending on properties of the organic compound....

  8. cDNA structure, genomic organization and expression patterns of ...

    African Journals Online (AJOL)

    use

    2011-11-23

    Nov 23, 2011 ... adenine dinucleotide (NAD) intermediate (Rongvaux et al., 2002). Thereupon ... in house mouse, Norway rat and human. It was not difficult to ... species in freshwater regions, and has been a new model organism in aquatic ...

  9. Discovery and structure determination of the orphan enzyme isoxanthopterin deaminase .

    Science.gov (United States)

    Hall, Richard S; Agarwal, Rakhi; Hitchcock, Daniel; Sauder, J Michael; Burley, Stephen K; Swaminathan, Subramanyam; Raushel, Frank M

    2010-05-25

    Two previously uncharacterized proteins have been identified that efficiently catalyze the deamination of isoxanthopterin and pterin 6-carboxylate. The genes encoding these two enzymes, NYSGXRC-9339a ( gi|44585104 ) and NYSGXRC-9236b ( gi|44611670 ), were first identified from DNA isolated from the Sargasso Sea as part of the Global Ocean Sampling Project. The genes were synthesized, and the proteins were subsequently expressed and purified. The X-ray structure of Sgx9339a was determined at 2.7 A resolution (Protein Data Bank entry 2PAJ ). This protein folds as a distorted (beta/alpha)(8) barrel and contains a single zinc ion in the active site. These enzymes are members of the amidohydrolase superfamily and belong to cog0402 within the clusters of orthologous groups (COG). Enzymes in cog0402 have previously been shown to catalyze the deamination of guanine, cytosine, S-adenosylhomocysteine, and 8-oxoguanine. A small compound library of pteridines, purines, and pyrimidines was used to probe catalytic activity. The only substrates identified in this search were isoxanthopterin and pterin 6-carboxylate. The kinetic constants for the deamination of isoxanthopterin with Sgx9339a were determined to be 1.0 s(-1), 8.0 muM, and 1.3 x 10(5) M(-1) s(-1) (k(cat), K(m), and k(cat)/K(m), respectively). The active site of Sgx9339a most closely resembles the active site for 8-oxoguanine deaminase (Protein Data Bank entry 2UZ9 ). A model for substrate recognition of isoxanthopterin by Sgx9339a was proposed on the basis of the binding of guanine and xanthine in the active site of guanine deaminase. Residues critical for substrate binding appear to be conserved glutamine and tyrosine residues that form hydrogen bonds with the carbonyl oxygen at C4, a conserved threonine residue that forms hydrogen bonds with N5, and another conserved threonine residue that forms hydrogen bonds with the carbonyl group at C7. These conserved active site residues were used to identify 24 other genes

  10. Discovery and Structure Determination of the Orphan Enzyme Isoxanthopterin Deaminase

    Energy Technology Data Exchange (ETDEWEB)

    Hall, R.S.; Swaminathan, S.; Agarwal, R.; Hitchcock, D.; Sauder, J. M.; Burley, S. K.; Raushel, F. M.

    2010-05-25

    Two previously uncharacterized proteins have been identified that efficiently catalyze the deamination of isoxanthopterin and pterin 6-carboxylate. The genes encoding these two enzymes, NYSGXRC-9339a (gi|44585104) and NYSGXRC-9236b (gi|44611670), were first identified from DNA isolated from the Sargasso Sea as part of the Global Ocean Sampling Project. The genes were synthesized, and the proteins were subsequently expressed and purified. The X-ray structure of Sgx9339a was determined at 2.7 {angstrom} resolution (Protein Data Bank entry 2PAJ). This protein folds as a distorted ({beta}/{alpha}){sub 8} barrel and contains a single zinc ion in the active site. These enzymes are members of the amidohydrolase superfamily and belong to cog0402 within the clusters of orthologous groups (COG). Enzymes in cog0402 have previously been shown to catalyze the deamination of guanine, cytosine, S-adenosylhomocysteine, and 8-oxoguanine. A small compound library of pteridines, purines, and pyrimidines was used to probe catalytic activity. The only substrates identified in this search were isoxanthopterin and pterin 6-carboxylate. The kinetic constants for the deamination of isoxanthopterin with Sgx9339a were determined to be 1.0 s{sup -1}, 8.0 {micro}M, and 1.3 x 10{sup 5} M{sup -1} s{sup -1} (k{sub cat}, K{sub m}, and k{sub cat}/K{sub m}, respectively). The active site of Sgx9339a most closely resembles the active site for 8-oxoguanine deaminase (Protein Data Bank entry 2UZ9). A model for substrate recognition of isoxanthopterin by Sgx9339a was proposed on the basis of the binding of guanine and xanthine in the active site of guanine deaminase. Residues critical for substrate binding appear to be conserved glutamine and tyrosine residues that form hydrogen bonds with the carbonyl oxygen at C4, a conserved threonine residue that forms hydrogen bonds with N5, and another conserved threonine residue that forms hydrogen bonds with the carbonyl group at C7. These conserved active site

  11. Effects of commercial organic fertilizers on the yield and yield structure of potato cultivars

    Directory of Open Access Journals (Sweden)

    Filipović Vladimir

    2012-01-01

    Full Text Available The research work has dealt with investigations of two type commercial organic fertilizers (DCM ECO-MIX 4 NPK 7:7:10 i GUANITO NPK 6:15:3 effects on the yield and yield structure of three potato cultivars (Cleopatra, Carrera and Sylvana. The control variant was used in plots without the use of organic fertilizers. The field experiment was performed in 2012. in a populated area Dobrica (N 45° 13’, E 20° 51’, 78 m.s.l. at the experimental farm plot Belča on which is certified organic production, on anthropogenic soil subtype chernozem on carbonate terrace. The results of research showed that the lowest tuber yield was determined in the control treatment (20,87 t ha-1, while the highest yield was achieved with a commercial organic fertilizer DCM ECO-MIX 4 (23,96 t ha-1. Number of tubers per plant corresponded to the characteristics of the studied cultivars. The largest number of tubers per plant was correlated with yield. Specifically, individual variants of the two greatest yields had the highest average number of tubers per plant. Cultivar Cleopatra of variant with GUANITO achieved 17,51 tubers per plant, while cultivar Sylvana of variant with DCM ECO-MIX 4 achieved 17,38 tubers per plant.

  12. Structural investigations of silicon nanostructures grown by self-organized island formation for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Roczen, Maurizio; Malguth, Enno; Barthel, Thomas; Gref, Orman; Toefflinger, Jan A.; Schoepke, Andreas; Schmidt, Manfred; Ruske, Florian; Korte, Lars; Rech, Bernd [Institute for Silicon Photovoltaics, Helmholtz-Zentrum Berlin, Berlin (Germany); Schade, Martin; Leipner, Hartmut S. [Martin-Luther-Universitaet Halle-Wittenberg, Interdisziplinaeres Zentrum fuer Materialwissenschaften, Halle (Germany); Callsen, Gordon; Hoffmann, Axel [Technische Universitaet Berlin, Institut fuer Festkoerperphysik, Berlin (Germany); Phillips, Matthew R. [University of Technology Sydney, Department of Physics and Advanced Materials, NSW (Australia)

    2012-09-15

    The self-organized growth of crystalline silicon nanodots and their structural characteristics are investigated. For the nanodot synthesis, thin amorphous silicon (a-Si) layers with different thicknesses have been deposited onto the ultrathin (2 nm) oxidized (111) surface of Si wafers by electron beam evaporation under ultrahigh vacuum conditions. The solid phase crystallization of the initial layer is induced by a subsequent in situ annealing step at 700 C, which leads to the dewetting of the initial a-Si layer. This process results in the self-organized formation of highly crystalline Si nanodot islands. Scanning electron microscopy confirms that size, shape, and planar distribution of the nanodots depend on the thickness of the initial a-Si layer. Cross-sectional investigations reveal a single-crystalline structure of the nanodots. This characteristic is observed as long as the thickness of the initial a-Si layer remains under a certain threshold triggering coalescence. The underlying ultra-thin oxide is not structurally affected by the dewetting process. Furthermore, a method for the fabrication of close-packed stacks of nanodots is presented, in which each nanodot is covered by a 2 nm thick SiO{sub 2} shell. The chemical composition of these ensembles exhibits an abrupt Si/SiO{sub 2} interface with a low amount of suboxides. A minority charge carrier lifetime of 18 {mu}s inside of the nanodots is determined. (orig.)

  13. Integrated Structural Biology for α-Helical Membrane Protein Structure Determination.

    Science.gov (United States)

    Xia, Yan; Fischer, Axel W; Teixeira, Pedro; Weiner, Brian; Meiler, Jens

    2018-04-03

    While great progress has been made, only 10% of the nearly 1,000 integral, α-helical, multi-span membrane protein families are represented by at least one experimentally determined structure in the PDB. Previously, we developed the algorithm BCL::MP-Fold, which samples the large conformational space of membrane proteins de novo by assembling predicted secondary structure elements guided by knowledge-based potentials. Here, we present a case study of rhodopsin fold determination by integrating sparse and/or low-resolution restraints from multiple experimental techniques including electron microscopy, electron paramagnetic resonance spectroscopy, and nuclear magnetic resonance spectroscopy. Simultaneous incorporation of orthogonal experimental restraints not only significantly improved the sampling accuracy but also allowed identification of the correct fold, which is demonstrated by a protein size-normalized transmembrane root-mean-square deviation as low as 1.2 Å. The protocol developed in this case study can be used for the determination of unknown membrane protein folds when limited experimental restraints are available. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Structure of rhenium (5) complexes with petroleum organic sulfur compounds

    International Nuclear Information System (INIS)

    Akhmadieva, R.G.; Yusupova, N.A.; Numanov, N.U.; Basitova, S.M.

    1985-01-01

    Structure of Re(5) complexes with petroleum sulfides (L) of ReOCl 3 (L) 2 composition is studied by the UV- and IR-spectroscopy method in a short-wave and long-wave ranges. It is shown that Re(5) complex with L are of the form of flattened octahedron,where three Cl atoms and one L molecule are arranged in the plane around Re atom. The structure is analogous to structure of Re complexes with synthetic cyclic sulfides

  15. Organization Strategy and Structural Differences for Radical Versus Incremental Innovation

    OpenAIRE

    John E. Ettlie; William P. Bridges; Robert D. O'Keefe

    1984-01-01

    The purpose of this study was to test a model of the organizational innovation process that suggests that the strategy-structure causal sequence is differentiated by radical versus incremental innovation. That is, unique strategy and structure will be required for radical innovation, especially process adoption, while more traditional strategy and structure arrangements tend to support new product introduction and incremental process adoption. This differentiated theory is strongly supported ...

  16. Structural Ordering of Semiconducting Polymers and Small-Molecules for Organic Electronics

    Science.gov (United States)

    O'Hara, Kathryn Allison

    comparable to quadrites were discovered in the semiconducting polymer, PSBTBT, where the angle of chain overlap could be predicted by the geometry of the backbone and alkyl side-chains. Such structures are hypothesized to improve the electronic connectivity and enable 3D transport. Now, it has been determined that another semiconducting polymer, PBDTTPD, forms cross-chain structures in thin films. PBDTTPD is a low band-gap donor-acceptor copolymer used in high efficiency OPVs. The effect of the alkyl side-chains on intercrystallite order is determined by examining three different derivatives of the PBDTTPD polymer with HRTEM. Additionally, the expansion and contraction of films during thermal annealing and slow cooling is monitored through in-situ grazing incidence wide-angle X-ray scattering (GIWAXS) measurements. Results show that minor variations in side-chain structure drive both crystallite orientation and the formation of crossed structures. Overall, these studies suggest design principles to continue to advance the field of organic electronics.

  17. An Examination of the Determinants of Organizational Structure.

    Science.gov (United States)

    Cheng-Kuang, Hsu; And Others

    1983-01-01

    Organizational context, organizational complexity, and bureaucratic control in 50 Japanese industrial manufacturing plants are analyzed. Highly dependent organizations rely on centralization and formalization to maintain administrative control. The significant relationship between formalization and centralization indicates that they are not…

  18. Organization structure as a moderator of the relationship between procedural justice, interactional justice, perceived organizational support, and supervisory trust.

    Science.gov (United States)

    Ambrose, Maureen L; Schminke, Marshall

    2003-04-01

    Organizational justice researchers recognize the important role organization context plays in justice perceptions, yet few studies systematically examine contextual variables. This article examines how 1 aspect of context--organizational structure--affects the relationship between justice perceptions and 2 types of social exchange relationships, organizational and supervisory. The authors suggest that under different structural conditions, procedural and interactional justice will play differentially important roles in determining the quality of organizational social exchange (as evidenced by perceived organizational support [POS]) and supervisory social exchange (as evidenced by supervisory trust). In particular, the authors hypothesized that the relationship between procedural justice and POS would be stronger in mechanistic organizations and that the relationship between interactional justice and supervisory trust would be stronger in organic organizations. The authors' results support these hypotheses.

  19. Teachers' Organization of Participation Structures for Teaching Science with Computer Technology

    Science.gov (United States)

    Subramaniam, Karthigeyan

    2016-01-01

    This paper describes a qualitative study that investigated the nature of the participation structures and how the participation structures were organized by four science teachers when they constructed and communicated science content in their classrooms with computer technology. Participation structures focus on the activity structures and…

  20. Quantitative determination of uranium in organic solution by X-ray fluorescence

    International Nuclear Information System (INIS)

    Leyt, D.V. de; Colangelo, C.H.

    1987-01-01

    An X-ray fluorescent method for the determination of uranium in tributilphosphate-kerosene-nitriacid solution has been developed. Chemical properties of the matrix elements were studied in order to select a convenient procedure to determine samples and standards on the same way. The method avoids the destruction of the organic material and has proved to be very useful for the fast control of uranium concentration. (Author) [es

  1. Utilization of organic reagents in the volumetric determination of micro-quantities of iodine

    International Nuclear Information System (INIS)

    Gantchev, N.; Kireva, A.

    1975-01-01

    A method has been developed for the titrimetric determination of micro-quantities of iodine by means of the organic reagents: Chrompyrazol I and Methylene blue. The recommended method is based on the combination of the extraction and volumetric methods and permits the titration of as little as 1 μg of I-/ml. The determination is not impaired by the ions: Br-, Cl-, NO 3 - and SO 4 2 -. (author)

  2. Self-organization of muscle cell structure and function.

    Directory of Open Access Journals (Sweden)

    Anna Grosberg

    2011-02-01

    Full Text Available The organization of muscle is the product of functional adaptation over several length scales spanning from the sarcomere to the muscle bundle. One possible strategy for solving this multiscale coupling problem is to physically constrain the muscle cells in microenvironments that potentiate the organization of their intracellular space. We hypothesized that boundary conditions in the extracellular space potentiate the organization of cytoskeletal scaffolds for directed sarcomeregenesis. We developed a quantitative model of how the cytoskeleton of neonatal rat ventricular myocytes organizes with respect to geometric cues in the extracellular matrix. Numerical results and in vitro assays to control myocyte shape indicated that distinct cytoskeletal architectures arise from two temporally-ordered, organizational processes: the interaction between actin fibers, premyofibrils and focal adhesions, as well as cooperative alignment and parallel bundling of nascent myofibrils. Our results suggest that a hierarchy of mechanisms regulate the self-organization of the contractile cytoskeleton and that a positive feedback loop is responsible for initiating the break in symmetry, potentiated by extracellular boundary conditions, is required to polarize the contractile cytoskeleton.

  3. Self-organization of muscle cell structure and function.

    Science.gov (United States)

    Grosberg, Anna; Kuo, Po-Ling; Guo, Chin-Lin; Geisse, Nicholas A; Bray, Mark-Anthony; Adams, William J; Sheehy, Sean P; Parker, Kevin Kit

    2011-02-01

    The organization of muscle is the product of functional adaptation over several length scales spanning from the sarcomere to the muscle bundle. One possible strategy for solving this multiscale coupling problem is to physically constrain the muscle cells in microenvironments that potentiate the organization of their intracellular space. We hypothesized that boundary conditions in the extracellular space potentiate the organization of cytoskeletal scaffolds for directed sarcomeregenesis. We developed a quantitative model of how the cytoskeleton of neonatal rat ventricular myocytes organizes with respect to geometric cues in the extracellular matrix. Numerical results and in vitro assays to control myocyte shape indicated that distinct cytoskeletal architectures arise from two temporally-ordered, organizational processes: the interaction between actin fibers, premyofibrils and focal adhesions, as well as cooperative alignment and parallel bundling of nascent myofibrils. Our results suggest that a hierarchy of mechanisms regulate the self-organization of the contractile cytoskeleton and that a positive feedback loop is responsible for initiating the break in symmetry, potentiated by extracellular boundary conditions, is required to polarize the contractile cytoskeleton.

  4. Synthesis and Structure Determination of Large-Pore Zeolite SCM-14.

    Science.gov (United States)

    Luo, Yi; Smeets, Stef; Peng, Fei; Etman, Ahmed S; Wang, Zhendong; Sun, Junliang; Yang, Weimin

    2017-11-27

    SCM-14 (Sinopec Composite Material No. 14), a new stable germanosilicate zeolite with a 12×8×8-ring channel system, was synthesized using commercially available 4-pyrrolidinopyridine as organic structure-directing agents (OSDAs) in fluoride medium. The framework structure of SCM-14 was determined using rotation electron diffraction (RED), and refined against synchrotron X-ray powder diffraction (SXPD) data for both as-made and calcined materials. The framework structure of SCM-14 is closely related to that of three known zeolites: mordenite (MOR), GUS-1 (GON), and IM-16 (UOS). SCM-14 has the same projection as that of mordenite and GUS-1 when viewed along the 12-ring channels, and possesses two more straight 8-ring channels running perpendicular to the 12-ring channels. The structure of SCM-14 can be constructed by either the same layers as that of GUS-1 or the same columns as that of IM-16. Based on their structural relationship, three topologically reasonable hypothetical zeolites were predicted. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. System-wide organization of actin cytoskeleton determines organelle transport in hypocotyl plant cells

    Science.gov (United States)

    Nowak, Jacqueline; Ivakov, Alexander; Somssich, Marc; Persson, Staffan; Nikoloski, Zoran

    2017-01-01

    The actin cytoskeleton is an essential intracellular filamentous structure that underpins cellular transport and cytoplasmic streaming in plant cells. However, the system-level properties of actin-based cellular trafficking remain tenuous, largely due to the inability to quantify key features of the actin cytoskeleton. Here, we developed an automated image-based, network-driven framework to accurately segment and quantify actin cytoskeletal structures and Golgi transport. We show that the actin cytoskeleton in both growing and elongated hypocotyl cells has structural properties facilitating efficient transport. Our findings suggest that the erratic movement of Golgi is a stable cellular phenomenon that might optimize distribution efficiency of cell material. Moreover, we demonstrate that Golgi transport in hypocotyl cells can be accurately predicted from the actin network topology alone. Thus, our framework provides quantitative evidence for system-wide coordination of cellular transport in plant cells and can be readily applied to investigate cytoskeletal organization and transport in other organisms. PMID:28655850

  6. Chemical Structure of Insoluble Organic Matter of Meteorites

    Science.gov (United States)

    Derenne, S.; Robert, F.; Binet, L.; Gourier, D.; Rouzaud, J.-N.; Largeau, C.

    A detailed knowledge of the insoluble organic matter (IOM) of the meteorites is essential to estimate to what extent the interstellar organic matter was preserved during the formation of the solar system and to decipher the synthetic pathways of this matter in space. Although predominant, the insoluble organic fraction has been much less extensively studied than soluble one due to specific analytical difficulties. The present work reports the examination of the IOM of two carbonaceous meteorites, Orgueil and Murchison through a number of various spectroscopic and microscopic methods, i. e. XANES for sulphur, carbon and nitrogen, solid state 13C NMR, electron paramagnetic resonance, electron nuclear double resonance and high resolution transmission electron microscopy.

  7. INMARSAT - The International Maritime Satellite Organization: Origins and structure

    Science.gov (United States)

    Doyle, S. E.

    1977-01-01

    The third session of the International Conference on the Establishment of an International Maritime Satellite System established the International Maritime Satellite Organization (INMARSAT) in 1976. Its main functions are to improve maritime communications via satellite, thereby facilitating more efficient emergency communications, ship management, and maritime public correspondence services. INMARSAT's aims are similar to those of the Intergovernmental Maritime Consultative Organization (IMCO), the main United Nations organization dealing with maritime affairs. The specific functions of INMARSAT have been established by an Intersessional Working Group (IWG) which met three times between general conference meetings. Initial investment shares for the creation of INMARSAT were shared by the United States (17%), the United Kingdom (12%), the U.S.S.R. (11%), Norway (9.50%), Japan (8.45%), Italy (4.37%), and France (3.50%).

  8. Research on Structure Innovation of Agricultural Organization in China’s Southwestern Mountainous Regions

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Taking agricultural organization in China’s southwestern mountainous regions as research object,on the basis of analysis of the status quo of agricultural organization development in China’s southwestern mountainous regions,we use related theoretical knowledge on economics and organization science,we probe into the process of innovation and mechanism of action concerning the structure of agricultural organization in China’s southwestern mountainous regions over the past 30 years.Finally we draw several general conclusions regarding structure innovation of agricultural organization in China’s southwestern mountainous regions as follows:first,the structure innovation of agricultural organization,a gradual process,proceeds ceaselessly along with ongoing progress and development of agriculture,and in this process,farmers always play a fundamental role;second,the structure innovation of agricultural organization is affected by many factors,and government institutional arrangement and change in market conditions is undoubtedly the most critical factor;third,the probable evolving direction of structure innovation of agricultural organization includes internal differentiation of the same form of agricultural organization,association of different forms of agricultural organization,and emergence of other forms of agricultural organization.

  9. Organic structures design applications in optical and electronic devices

    CERN Document Server

    Chow, Tahsin J

    2014-01-01

    ""Presenting an overview of the syntheses and properties of organic molecules and their applications in optical and electronic devices, this book covers aspects concerning theoretical modeling for electron transfer, solution-processed micro- and nanomaterials, donor-acceptor cyclophanes, molecular motors, organogels, polyazaacenes, fluorogenic sensors based on calix[4]arenes, and organic light-emitting diodes. The publication of this book is timely because these topics have become very popular nowadays. The book is definitely an excellent reference for scientists working in these a

  10. Flexible organic solar cells including efficiency enhancing grating structures

    DEFF Research Database (Denmark)

    Oliveira Hansen, Roana Melina de; Liu, Yinghui; Madsen, Morten

    2013-01-01

    , such as photolithography and electron-beam lithography, besides the steps required for the bulk-heterojunction organic solar cell fabrication. After the production steps, the solar cells on polyimide are peeled off the silicon support substrates, resulting in flexible devices containing nanostructures for light absorption......In this work, a new method for the fabrication of organic solar cells containing functional light-trapping nanostructures on flexible substrates is presented. Polyimide is spin-coated on silicon support substrates, enabling standard micro- and nanotechnology fabrication techniques...

  11. Determination of comprehensive arterial blood inflow in abdominal-pelvic organs: impact of respiration and posture on organ perfusion.

    Science.gov (United States)

    Osada, Takuya; Nagata, Hiroyasu; Murase, Norio; Kime, Ryotaro; Katsumura, Toshihito

    2011-02-01

    Arterial blood flow (BF) to all abdominal-pelvic organs (AP) shows potential for an indicator of comprehensive splanchnic organ circulation (reservoir of blood supply for redistribution) in cardiovascular disease, hepato-gastrointestinal disease or hemodynamic disorders. Our previous assessment of splanchnic hemodynamics, as magnitude of BFAP [measuring by subtracting BF in both femoral arteries (FAs) from the upper abdominal aorta (Ao) above the celiac trunk] using Doppler ultrasound, was reported as the relationship between Ao and FAs, day-to-day variability and response to exercise. For accurate determination of BFAP, it is important to consider the various factors that potentially influence BFAP. However, little information exists regarding the influence of respiration (interplay between inspiration and expiration) and posture on BFAP. Ten healthy males were evaluated in sitting/supine positions following a 12 hr fast. Magnitude of BFAP was determined as measurement of Ao and FAs hemodynamics (blood velocity and vessel diameter) using pulsed Doppler with spectral analysis during spontaneous 4-sec inspiration/4-sec expiration phases. BF/blood velocity in the Ao and FAs showed significant lower in inspiration than expiration. BFAP showed a significant (Ppressure during breathing (thoracic-abdominal movement) is possibly reflecting transient changes in blood velocity in the Ao and FAs. Respiratory effects should be taken into account for evaluation of BFAP.

  12. 47 CFR 90.1408 - Organization and structure of the 700 MHz public/private partnership.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Organization and structure of the 700 MHz public/private partnership. 90.1408 Section 90.1408 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Partnership § 90.1408 Organization and structure of the 700 MHz public/private partnership. (a) The Upper 700...

  13. 47 CFR 27.1308 - Organization and structure of the 700 MHz public/private partnership.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Organization and structure of the 700 MHz public/private partnership. 27.1308 Section 27.1308 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Partnership § 27.1308 Organization and structure of the 700 MHz public/private partnership. (a) The Upper 700...

  14. Determination of the transport levels in thin films of organic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Stefan

    2009-07-27

    The approach of using the combination of Ultraviolet (UPS) and Inverse Photoemission (IPS) to determine the transport levels in thin films of organic semiconductors is the scope of this work. For this matter all influences on the peak position and width in Photoelectron Spectroscopy are discussed with a special focus on organic semiconductors. Many of these influences are shown with experimental results of the investigation of diindenoperylene on Ag(111). These findings are applied to inorganic semiconductors silicon in order to establish the use of UPS and IPS on a well-understood system. Finally, the method is used to determine the transport level of several organic semiconductors (PTCDA, Alq3, CuPc, DIP, PBI-H4) and the corresponding exciton binding energies are calculated by comparison to optical absorption data. (orig.)

  15. Determination of organic-bound chlorine and bromine in human body fluids by neutron activation analysis

    International Nuclear Information System (INIS)

    McKinney, J.D.; Abusamra, A.; Reed, J.H.

    1983-01-01

    The levels of organic-bound chlorine and bromine in human milk and serum are determined by neutron activation analysis. Desalted milk and serum fractions are irradiated with neutrons in a nuclear reactor and the resulting γ-rays of 38 Cl and 80 Br are measured. The desalting procedure, achieved by using Bio-Gel molecular sieves, virtually removes all ionic chloride and bromides from milk and serum. Radioactive tracer studies with polychlorinated biphenyl- 14 C indicate a recovery of 90% through the Bio-Gel column. The total organic chlorine in 2.2-(4-chlorophenyl)-1,1-dichloroethane spiked milk and heptachlor spiked milk, determined after being desalted and irradiated according to this procedure, substantiates a good recovery of the added spike. The lower limits of detection of organic-bound chlorine and bromine in milk or serum are 50 and 5 parts per billion (ppb), respectively

  16. Determination of alcohols, ethers and organic acids in irradiated sweet potato wine by capillary gas chromatography

    International Nuclear Information System (INIS)

    Zhou Yingcai; Yuan Bihuai; Xu Peishu; Wang Xiuying

    1986-01-01

    Alcohols, ethers and organic acids in irradiated sweet potato wine have been determined with capillary GC. The results show that the contents of some components have changed after irradiation, but no new species are formed. The G values of the changed components have been calculated

  17. Chiral Organic Cages with a Triple-Stranded Helical Structure Derived from Helicene.

    Science.gov (United States)

    Malik, Abaid Ullah; Gan, Fuwei; Shen, Chengshuo; Yu, Na; Wang, Ruibin; Crassous, Jeanne; Shu, Mouhai; Qiu, Huibin

    2018-02-28

    We report the use of helicene with an intrinsic helical molecular structure to prepare covalent organic cages via imine condensation. The organic cages revealed a [3+2]-type architecture containing a triple-stranded helical structure with three helicene units arranged in a propeller-like fashion with the framework integrally twisted. Such structural chirality was retained upon dissolution in organic solvents, as indicated by a strong diastereotopy effect in proton NMR and unique Cotton effects in circular dichroism spectra. Further study on chiral adsorption showed that the chiral organic cages possess considerable enantioselectivity toward a series of aromatic racemates.

  18. Organic nitrogen rearranges both structure and activity of the soil-borne microbial seedbank

    NARCIS (Netherlands)

    Leite, Márcio F.A.; Pan, Yao; Bloem, Jaap; Berge, ten Hein; Kuramae, Eiko E.

    2017-01-01

    Use of organic amendments is a valuable strategy for crop production. However, it remains unclear how organic amendments shape both soil microbial community structure and activity, and how these changes impact nutrient mineralization rates. We evaluated the effect of various organic amendments,

  19. Interracial Friendship and Structural Diversity: Trends for Greek, Religious, and Ethnic Student Organizations

    Science.gov (United States)

    Park, Julie J.; Kim, Young K.

    2013-01-01

    This article examines how peer interactions in college organizations (Greek, ethnic, and religious) affect interracial friendships, including whether peer interaction in student organizations mediates the relationship between structural diversity and interracial friendship. Involvement in ethnic student organizations was non-significant;…

  20. Organic nitrogen rearranges both structure and activity of the soil-borne microbial seedbank

    NARCIS (Netherlands)

    Leite, M.F.A.; Pan, Y.; Bloem, J.; ten Berge, H.; Kuramae, E.E.

    2017-01-01

    Use of organic amendments is a valuable strategy for crop production. However, it remains unclear how organic amendments shape both soil microbial community structure and activity, and how these changes impact nutrient mineralization rates. We evaluated the effect of various organic amendments,

  1. The Influence of Content Organization on Student's Cognitive Structure in Thermodynamics.

    Science.gov (United States)

    Moreira, Marco A.; Santos, Carlos A.

    1981-01-01

    Two approaches to the content of thermodynamics were used in an introductory college physics course: traditional organization and organization based on Ausubel's learning theory. The influence of these organizations on engineering student's (N=58) cognitive structure was investigated using a word association test analyzed through hierarchical…

  2. Organized turbulent motions in a hedgerow vineyard: effect of evolving canopy structure

    Science.gov (United States)

    Vendrame, Nadia; Tezza, Luca; Tha Paw U, Kyaw; Pitacco, Andrea

    2017-04-01

    Vegetation-atmosphere exchanges are determined by functional and structural properties of the plants together with environmental forcing. However, a fundamental aspect is the interaction of the canopy with the lower atmosphere. The vegetation deeply alters the composition and physical properties of the air flow, exchanging energy, matter and momentum with it. These processes take place in the bottom part of the atmospheric boundary layer where turbulence is the main mechanism transporting within-canopy air towards the mid- and upper atmospheric boundary layer and vice versa. Canopy turbulence is highly influenced by vegetation drag elements, determining the vertical profile of turbulent moments within the canopy. Canopies organized in rows, like vineyards, show peculiar turbulent transport dynamics. In addition, the morphological structure (phenology) of the vineyard is greatly variable seasonally, shifting from an empty canopy during vine dormancy to dense foliage in summer. The understanding of the canopy ventilation regime is related to several practical applications in vineyard management. For example, within-canopy turbulent motion is very important to predict small particles dispersion, like fungal spores, and minimize infection studying the effect on leaf wetness duration. Our study aims to follow the continuous evolution of turbulence characteristics and canopy structure during the growing season of a hedgerow vineyard, from bud break to fully developed canopy. The field experiment was conducted in a flat extensive vineyard in North-Eastern Italy, using a vertical array of five synchronous sonic anemometers within and above the canopy. Turbulent flow organization was greatly influenced by canopy structure. Turbulent coherent structures involved in momentum transport have been investigated using the classical quadrant analysis and a novel approach to identify dominant temporal scales. Momentum transport in the canopy was dominated by downward gusts showing

  3. Determination of solute organic concentration in contaminated soils using a chemical-equilibrium soil column system

    DEFF Research Database (Denmark)

    Gamst, Jesper; Kjeldsen, Peter; Christensen, Thomas Højlund

    2007-01-01

    using two soils with different content of organic carbon (f(oc) of 1.5 and 6.5%, respectively). A quadruple blind test of the ER-V system using glass beads in stead of soil showed an acceptable recovery (65-85%) of all of the 11 VOCs tested. Only for the most volatile compound (heptane, K-H similar...... to 80) an unacceptable recovery was found (9%). The contact time needed for obtaining chemical equilibrium was tested in the ER-H system by performing five test with different duration (1, 2, 4, 7 and 19 days) using the low organic carbon soil. Seven days of contact time appeared sufficient...... for determination of solute concentration in a contaminated soil were developed; (1) a chemical Equilibrium and Recirculation column test for Volatile organic chemicals (ER-V) and (2) a chemical Equilibrium and Recirculation column test for Hydrophobic organic chemicals (ER-H). The two test systems were evaluated...

  4. CCDC 1408042: Experimental Crystal Structure Determination : 6,13-dimesitylpentacene

    KAUST Repository

    Shi, Xueliang

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  5. CCDC 1416891: Experimental Crystal Structure Determination : Methyl-triphenyl-germanium

    KAUST Repository

    Bernatowicz, Piotr

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  6. Higher Educational Consortia Organization: Functional Structures of Administration and Management.

    Science.gov (United States)

    Lepchenske, George L.

    The administrative and functional organization of higher education consortia are discussed. The need for cooperation between individual institutions has been established; one lone institution cannot encompass all knowledge generated. The rapid growth of consortia has generated extensive services, funding sources, developmental activities,…

  7. Organizing Innovation within Incumbent Firms: Structure Enabling Strategic Autonomy

    NARCIS (Netherlands)

    van Looy, Bart; van Looy, Bart; Visscher, Klaasjan

    2011-01-01

    In this paper we will discuss how large established firms can be effective in organizing innovation alongside their current business. We examine the trajectory of an incumbent firm in the telecommunication industry – Alcatel – which has been successful in exploring and exploiting the promises of

  8. Organizational Structures and Data Use in Volunteer Monitoring Organizations (VMOs)

    Science.gov (United States)

    Laird, Shelby Gull; Nelson, Stacy A. C.; Stubbs, Harriett S.; James, April L.; Menius, Erika

    2012-01-01

    Complex environmental problems call for unique solutions to monitoring efforts alongside developing a more environmentally literate citizenry. Community-based monitoring (CBM) through the use of volunteer monitoring organizations helps to provide a part of the solution, particularly when CBM groups work with research scientists or government…

  9. Molecular structure impacts on secondary organic aerosol formation from glycol ethers

    Science.gov (United States)

    Li, Lijie; Cocker, David R.

    2018-05-01

    Glycol ethers, a class of widely used solvents in consumer products, are often considered exempt as volatile organic compounds based on their vapor pressure or boiling points by regulatory agencies. However, recent studies found that glycol ethers volatilize at ambient conditions nearly as rapidly as the traditional high-volatility solvents indicating the potential of glycol ethers to form secondary organic aerosol (SOA). This is the first work on SOA formation from glycol ethers. The impact of molecular structure, specifically -OH, on SOA formation from glycol ethers and related ethers are investigated in the work. Ethers with and without -OH, with methyl group hindrance on -OH and with -OH at different location are studied in the presence of NOX and under "NOX free" conditions. Photooxidation experiments under different oxidation conditions confirm that the processing of ethers is a combination of carbonyl formation, cyclization and fragmentation. Bulk SOA chemical composition analysis and oxidation products identified in both gas and particle phase suggests that the presence and location of -OH in the carbon bond of ethers determine the occurrence of cyclization mechanism during ether oxidation. The cyclization is proposed as a critical SOA formation mechanism to prevent the formation of volatile compounds from fragmentation during the oxidation of ethers. Glycol ethers with -CH2-O-CH2CH2OH structure is found to readily form cyclization products, especially with the presence of NOx, which is more relevant to urban atmospheric conditions than without NOx. Glycol ethers are evaluated as dominating SOA precursors among all ethers studied. It is estimated that the contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources. The contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources and will play a more important role in future anthropogenic SOA

  10. Determining the Mechanical Properties of Lattice Block Structures

    Science.gov (United States)

    Wilmoth, Nathan

    2013-01-01

    Lattice block structures and shape memory alloys possess several traits ideal for solving intriguing new engineering problems in industries such as aerospace, military, and transportation. Recent testing at the NASA Glenn Research Center has investigated the material properties of lattice block structures cast from a conventional aerospace titanium alloy as well as lattice block structures cast from nickel-titanium shape memory alloy. The lattice block structures for both materials were sectioned into smaller subelements for tension and compression testing. The results from the cast conventional titanium material showed that the expected mechanical properties were maintained. The shape memory alloy material was found to be extremely brittle from the casting process and only compression testing was completed. Future shape memory alloy lattice block structures will utilize an adjusted material composition that will provide a better quality casting. The testing effort resulted in baseline mechanical property data from the conventional titanium material for comparison to shape memory alloy materials once suitable castings are available.

  11. Quantitative x-ray structure determination of superlattices and interfaces

    International Nuclear Information System (INIS)

    Schuller, I.K.; Fullerton, E.E.

    1990-01-01

    This paper presents a general procedure for quantitative structural refinement of superlattice structures. To analyze a wide range of superlattices, the authors have derived a general kinematical diffraction formula that includes random, continuous and discrete fluctuations from the average structure. By implementing a non-linear fitting algorithm to fit the entire x-ray diffraction profile, refined parameters that describe the average superlattice structure, and deviations from this average are obtained. The structural refinement procedure is applied to a crystalline/crystalline Mo/Ni superlattices and crystalline/amorphous Pb/Ge superlattices. Roughness introduced artificially during growth in Mo/Ni superlattices is shown to be accurately reproduced by the refinement

  12. Structural versatility of Metal-organic frameworks: Synthesis and Characterization

    KAUST Repository

    Alsadun, Norah Sadun

    2017-01-01

    -targeted multi-nuclear Molecular Building Block (MBB) precursors to unveil materials with targeted structural characteristics is captivating. The aim of my master project in the continuous quest of the group of Prof. Eddaoudi in exploring different synthetic

  13. Simulation of Protein Structure, Dynamics and Function in Organic Media

    National Research Council Canada - National Science Library

    Daggett, Valerie

    1998-01-01

    The overall goal of our ONR-sponsored research is to pursue realistic molecular modeling strudies pertinnent to the related properties of protein stability, dynamics, structure, function, and folding in aqueous solution...

  14. [Correlation of codon biases and potential secondary structures with mRNA translation efficiency in unicellular organisms].

    Science.gov (United States)

    Vladimirov, N V; Likhoshvaĭ, V A; Matushkin, Iu G

    2007-01-01

    Gene expression is known to correlate with degree of codon bias in many unicellular organisms. However, such correlation is absent in some organisms. Recently we demonstrated that inverted complementary repeats within coding DNA sequence must be considered for proper estimation of translation efficiency, since they may form secondary structures that obstruct ribosome movement. We have developed a program for estimation of potential coding DNA sequence expression in defined unicellular organism using its genome sequence. The program computes elongation efficiency index. Computation is based on estimation of coding DNA sequence elongation efficiency, taking into account three key factors: codon bias, average number of inverted complementary repeats, and free energy of potential stem-loop structures formed by the repeats. The influence of these factors on translation is numerically estimated. An optimal proportion of these factors is computed for each organism individually. Quantitative translational characteristics of 384 unicellular organisms (351 bacteria, 28 archaea, 5 eukaryota) have been computed using their annotated genomes from NCBI GenBank. Five potential evolutionary strategies of translational optimization have been determined among studied organisms. A considerable difference of preferred translational strategies between Bacteria and Archaea has been revealed. Significant correlations between elongation efficiency index and gene expression levels have been shown for two organisms (S. cerevisiae and H. pylori) using available microarray data. The proposed method allows to estimate numerically the coding DNA sequence translation efficiency and to optimize nucleotide composition of heterologous genes in unicellular organisms. http://www.mgs.bionet.nsc.ru/mgs/programs/eei-calculator/.

  15. Perspectives of experimental and theoretical studies of self-organized dust structures in complex plasmas under microgravity conditions

    International Nuclear Information System (INIS)

    Tsytovich, V N

    2015-01-01

    We review research aimed at understanding the phenomena occurring in a complex plasma under microgravity conditions. Some aspects of the work already performed are considered that have not previously been given sufficient attention but which are potentially crucial for future work. These aspects, in particular, include the observation of compact dust structures that are estimated to be capable of confining all components of a dust plasma in a bounded spatial volume; experimental evidence of the nonlinear screening of dust particles; and experimental evidence of the excitation of collective electric fields. In theoretical terms, novel collective attraction processes between likely charged dust particles are discussed and all schemes of the shadowy attraction between dust particles used earlier, including in attempts to interpret observations, are reviewed and evaluated. Dust structures are considered from the standpoint of the current self-organization theory. It is emphasized that phase transitions between states of self-organized systems differ significantly from those in homogeneous states and that the phase diagrams should be constructed in terms of the parameters of a self-organized structure and cannot be constructed in terms of the temperature and density or similar parameters of homogeneous structures. Using the existing theoretical approaches to modeling self-organized structures in dust plasmas, the parameter distribution of a structure is recalculated for a simpler model that includes the quasineutrality condition and neglects diffusion. These calculations indicate that under microgravity conditions, any self-organized structure can contain a limited number of dust particles and is finite in size. The maximum possible number of particles in a structure determines the characteristic inter-grain distance in dust crystals that can be created under microgravity conditions. Crystallization criteria for the structures are examined and the quasispherical

  16. Determination of Innovation Capability of Organizations: Qualitative Meta Synthesis and Delphi Method

    DEFF Research Database (Denmark)

    Momeni, Mostafa; Nielsen, Susanne Balslev; Kafash, Mahdi Haghighi

    2015-01-01

    . The innovation capability is associated with other organizational capabilities. So, many organizations have focused on the need to identify innovation capabilities and resources or strengths in relation to external opportunities and threats according to inside-out view because innovation capability has...... capability in the organizations and this paper includes an expert based validation in three rounds of the Delphi method. This research proposed a direct relationship between Innovation Capability and three main capabilities that is called Structural Capability, Personnel Capability and Operational Capability...

  17. Organic-inorganic semiconductor hybrid systems. Structure, morphology, and electronic properties

    Energy Technology Data Exchange (ETDEWEB)

    El Helou, Mira

    2012-08-22

    This dissertation addresses the preparation and characterization of hybrid semiconducting systems combining organic with inorganic materials. Characterization methods used included to determine the structure, morphology, and thermal stability comprised X-ray diffraction (XRD), atomic force microscopy (AFM), thermal desorption spectroscopy (TDS), and X-ray photoelectron spectroscopy (XPS). One organic-inorganic semiconducting system was pentacene (C{sub 22}H{sub 14}) and zinc oxide. This interface was investigated in detail for pentacene on an oxygen-terminated zinc oxide surface, i.e. ZnO(000 anti 1). An extended study on the promising p-n junction was carried out for pentacene on ZnO with different orientations which exhibit different chemical and structural characteristics: ZnO(000 anti 1), ZnO(0001), and ZnO(10 anti 10). Moreover, the organic crystal structure of pentacene was selectively tuned by carefully choosing the substrate temperature. This defined interface with a physisorbed pentacene layer on ZnO was characterized by optical absorption which depends on the temperature of the measured system, the pentacene film thickness, and the molecular orientation and packing. The high quality of the pentacene films allowed in one case to characterize the Davydov splitting by linear polarized light focused on a single crystallite. Another subject in the field of organic-inorganic hybrid materials comprised conjugated dithiols used as self-assembled monolayers (SAMs) for immobilizing semiconducting CdS nanoparticles (NPs) on Au substrates. It was demonstrated that an appropriate selection and preparation of the conjugated SAMs is crucial for building up a light-addressable potentiometric sensor with a sufficient efficiency. An optimized electron transfer was achieved with SAMs of long range ordering, high stability, and adequate conductivity. This was examined for different linkers and was best for stilbenedithiol immobilized in solution at higher temperatures. Due

  18. Filamentary structures that self-organize due to adhesion

    Science.gov (United States)

    Sengab, A.; Picu, R. C.

    2018-03-01

    We study the self-organization of random collections of elastic filaments that interact adhesively. The evolution from an initial fully random quasi-two-dimensional state is controlled by filament elasticity, adhesion and interfilament friction, and excluded volume. Three outcomes are possible: the system may remain locked in the initial state, may organize into isolated fiber bundles, or may form a stable, connected network of bundles. The range of system parameters leading to each of these states is identified. The network of bundles is subisostatic and is stabilized by prestressed triangular features forming at bundle-to-bundle nodes, similar to the situation in foams. Interfiber friction promotes locking and expands the parametric range of nonevolving systems.

  19. Structural determinants of reductive terpene cyclization in iridoid biosynthesis

    DEFF Research Database (Denmark)

    Kries, Hajo; Caputi, Lorenzo; Stevenson, Clare E M

    2016-01-01

    The carbon skeleton of ecologically and pharmacologically important iridoid monoterpenes is formed in a reductive cyclization reaction unrelated to canonical terpene cyclization. Here we report the crystal structure of the recently discovered iridoid cyclase (from Catharanthus roseus) bound...

  20. Structure determination at room temperature and phase transition ...

    Indian Academy of Sciences (India)

    Unknown

    Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India. MS received 9 May 2002 ... exhibit a ferroelectric–paraelectric phase transition at ele- ..... The pattern decomposition and peak extraction methods ...

  1. WHAT DETERMINES THE CAPITAL STRUCTURE OF LISTED FIRMS IN ROMANIA

    Directory of Open Access Journals (Sweden)

    Floriniţa Duca

    2012-10-01

    Full Text Available This paper examines the relative importance of four factors in the capital structure decisions of Romanian listed firms. The existing empirical research on capital structure has been largely confined to developed countries. The Romanian Financial Market has been developing at an exponential rate and dedicated research in the field is required. We used 100 firms listed in 2010 at the Bucharest Stock Exchange. The objective of this paper is to build on previous studies model all the important factors affecting capital structure decisions. We find that factors such as tangibility of assets, firm size, liquidity, and profitability have significant influences on the leverage structure chosen by firms.These results are believed to have significant implications for the theory of finance and to be of importance to the corporate treasure in choice of new financing and to the financial analyst.

  2. Molecular evolution, intracellular organization, and the quinary structure of proteins.

    OpenAIRE

    McConkey, E H

    1982-01-01

    High-resolution two-dimensional polyacrylamide gel electrophoresis shows that at least half of 370 denatured polypeptides from hamster cells and human cells are indistinguishable in terms of isoelectric points and molecular weights. Molecular evolution may have been more conservative for this set of proteins than sequence studies on soluble proteins have implied. This may be a consequence of complexities of intracellular organization and the numerous macromolecular interactions in which most ...

  3. Organized Mesoporous Alumina: Synthesis, Structure and Potential in Catalysis

    Czech Academy of Sciences Publication Activity Database

    Čejka, Jiří

    2003-01-01

    Roč. 254, - (2003), s. 327-338 ISSN 0926-860X R&D Projects: GA AV ČR IAA4040001; GA ČR GA104/02/0571; GA MŠk ME 404 Institutional research plan: CEZ:AV0Z4040901 Keywords : organized mesoporous alumina * mesoporous molecular sieves * synthesis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.825, year: 2003

  4. Research on Structure Innovation of Agricultural Organization in China's Southwestern Mountainous Regions

    OpenAIRE

    Du, Qiang; Luo, Min; Wang, Ping

    2012-01-01

    Taking agricultural organization in China's southwestern mountainous regions as research object, on the basis of analysis of the status quo of agricultural organization development in China's southwestern mountainous regions, we use related theoretical knowledge on economics and organization science, we probe into the process of innovation and mechanism of action concerning the structure of agricultural organization in China's southwestern mountainous regions over the past 30 years. Finally w...

  5. Pineal organs of deep-sea fish: photopigments and structure.

    Science.gov (United States)

    Bowmaker, James K; Wagner, Hans-Joachim

    2004-06-01

    We have examined the morphology and photopigments of the pineal organs from a number of mesopelagic fish, including representatives of the hatchet fish (Sternoptychidae), scaly dragon-fish (Chauliodontidae) and bristlemouths (Gonostomidae). Although these fish were caught at depths of between 500 and 1000 m, the morphological organisation of their pineal organs is remarkably similar to that of surface-dwelling fish. Photoreceptor inner and outer segments protrude into the lumen of the pineal vesicle, and the outer segment is composed of a stack of up to 20 curved disks that form a cap-like cover over the inner segment. In all species, the pineal photopigment was spectrally distinct from the retinal rod pigment, with lambdamax displaced to longer wavelengths, between approximately 485 and 503 nm. We also investigated the pineal organ of the deep demersal eel, Synaphobranchus kaupi, caught at depths below 2000 m, which possesses a rod visual pigment with lambdamax at 478 nm, but the pineal pigment has lambdamax at approximately 515 nm. In one species of hatchet fish, Argyropelecus affinis, two spectral classes of pinealocyte were identified, both spectrally distinct from the retinal rod photopigment.

  6. Determination of basicity of neutral organic phosphorus extractants in nonpolar solvents by the 31P NMR method

    International Nuclear Information System (INIS)

    Yakshin, V.V.; Meshcheryakov, N.M.; Il'in, E.G.; Ignatov, M.E.; Laskorin, B.N.

    1984-01-01

    The variant of the NMR method application is developed for quantitative description of acidic-basic properties of neutral organic phosphorus extractants, R 3 P--O (NPE), in non-polar organic solvents. For the NPE basicity determination the dependence of the chemical shift value in NMR 31 P spectra of 0.1 M NPE solutions in the dodecane on sulfuric acid acitivity in aqueous phase at 0-12 M acidity is studied. The linear equation relating NPE basicity and electronic structure of these compounds expressed through the sum: of Kabachnik reaction constants is derived. Linear dependences between the NPE basicity value in dodecane and NPE basicity in nitromethane as well as enthalpies of complexes formation with charge transport with standard acid-iodine in heptane, enthalpies of hydrogen complexes formation with phenol and water have been found

  7. Assessment of relative accuracy in the determination of organic matter concentrations in aquatic systems

    Science.gov (United States)

    Aiken, G.; Kaplan, L.A.; Weishaar, J.

    2002-01-01

    Accurate determinations of total (TOC), dissolved (DOC) and particulate (POC) organic carbon concentrations are critical for understanding the geochemical, environmental, and ecological roles of aquatic organic matter. Of particular significance for the drinking water industry, TOC measurements are the basis for compliance with US EPA regulations. The results of an interlaboratory comparison designed to identify problems associated with the determination of organic matter concentrations in drinking water supplies are presented. The study involved 31 laboratories and a variety of commercially available analytical instruments. All participating laboratories performed well on samples of potassium hydrogen phthalate (KHP), a compound commonly used as a standard in carbon analysis. However, problems associated with the oxidation of difficult to oxidize compounds, such as dodecylbenzene sulfonic acid and caffeine, were noted. Humic substances posed fewer problems for analysts. Particulate organic matter (POM) in the form of polystyrene beads, freeze-dried bacteria and pulverized leaf material were the most difficult for all analysts, with a wide range of performances reported. The POM results indicate that the methods surveyed in this study are inappropriate for the accurate determination of POC and TOC concentration. Finally, several analysts had difficulty in efficiently separating inorganic carbon from KHP solutions, thereby biasing DOC results.

  8. Integrating centralized and decentralized organization structures: an education and development model.

    Science.gov (United States)

    Sheriff, R; Banks, A

    2001-01-01

    Organization change efforts have led to critically examining the structure of education and development departments within hospitals. This qualitative study evaluated an education and development model in an academic health sciences center. The model combines centralization and decentralization. The study results can be used by staff development educators and administrators when organization structure is questioned. This particular model maximizes the benefits and minimizes the limitations of centralized and decentralized structures.

  9. Evaluating the impact of investments in information technology on structural inertia in health organizations.

    Science.gov (United States)

    Bewley, Lee W

    2010-01-01

    Structural inertia is the overall capacity of an organization to adapt within a market environment. This paper reviews the impact of healthcare investments in information management/information technology (IM/IT) on the strategic management concept of structural inertia. Research indicates that healthcare executives should consider the relative state of structural inertia for their firms and match them with potential IM/IT solutions. Additionally, organizations should favorably consider IM/IT solutions that are comparatively less complex.

  10. Interactions between radionuclides and organic colloids. Structure and reactivity of humic compounds

    International Nuclear Information System (INIS)

    Plancque, G.

    2001-09-01

    Humic compounds are the main organic colloids present in natural waters. These compounds can significantly modify the speciation of metals and control their properties, like migration, toxicity or bio-availability. It is thus important to study their speciation in conditions representative to those encountered in the natural environment. The aim of this work is to analyze the reactivity of these humic compounds. Two spectroscopic techniques have been used: the time-resolution laser spectro-fluorimetry, limited to the study of fluorescent elements, and the electro-spray source mass spectroscopy which requires the development of specific protocols for all elements of the periodic classification system. Europium, a fluorescent element analogue to trivalent actinides, has been chosen as test-metal for the intercomparison of both spectroscopic techniques. The first technique has permitted to determine the inorganic and organic speciation (spectra and lifetime of europium hydroxides and carbonates, and constants of interaction with humic acids, respectively). The limitations of this technique in the study of inorganic speciation has been evidenced. Humic compounds have a badly defined structure. The use of high-resolution mass spectroscopy has permitted to propose in a direct and experimental way, a molecular structure of aquatic fulvic acids in agreement with their known physico-chemical properties. (J.S.)

  11. Self-Structured Organizing Single-Input CMAC Control for Robot Manipulator

    Directory of Open Access Journals (Sweden)

    ThanhQuyen Ngo

    2011-09-01

    Full Text Available This paper represents a self-structured organizing single-input control system based on differentiable cerebellar model articulation controller (CMAC for an n-link robot manipulator to achieve the high-precision position tracking. In the proposed scheme, the single-input CMAC controller is solely used to control the plant, so the input space dimension of CMAC can be simplified and no conventional controller is needed. The structure of single-input CMAC will also be self-organized; that is, the layers of single-input CMAC will grow or prune systematically and their receptive functions can be automatically adjusted. The online tuning laws of single-input CMAC parameters are derived in gradient-descent learning method and the discrete-type Lyapunov function is applied to determine the learning rates of proposed control system so that the stability of the system can be guaranteed. The simulation results of robot manipulator are provided to verify the effectiveness of the proposed control methodology.

  12. The filamins: organizers of cell structure and function.

    Science.gov (United States)

    Nakamura, Fumihiko; Stossel, Thomas P; Hartwig, John H

    2011-01-01

    Filamin A (FLNa), the first non-muscle actin filament cross-linking protein, was identified in 1975. Thirty five years of FLNa research has revealed its structure in great detail, discovered its isoforms (FLNb and c), and identified over 90 binding partners including channels, receptors, intracellular signaling molecules, and even transcription factors. Due to this diversity, mutations in human FLN genes result in a wide range of anomalies with moderate to lethal consequences. This review focuses on the structure and functions of FLNa in cell migration and adhesion.

  13. Diffusion and solubility coefficients determined by permeation and immersion experiments for organic solvents in HDPE geomembrane.

    Science.gov (United States)

    Chao, Keh-Ping; Wang, Ping; Wang, Ya-Ting

    2007-04-02

    The chemical resistance of eight organic solvents in high density polyethylene (HDPE) geomembrane has been investigated using the ASTM F739 permeation method and the immersion test at different temperatures. The diffusion of the experimental organic solvents in HDPE geomembrane was non-Fickian kinetic, and the solubility coefficients can be consistent with the solubility parameter theory. The diffusion coefficients and solubility coefficients determined by the ASTM F739 method were significantly correlated to the immersion tests (pHDPE as barriers in the field.

  14. Stem Cell Fate Determination during Development and Regeneration of Ectodermal Organs

    Science.gov (United States)

    Jiménez-Rojo, Lucía; Granchi, Zoraide; Graf, Daniel; Mitsiadis, Thimios A.

    2012-01-01

    The development of ectoderm-derived appendages results in a large variety of highly specialized organs such as hair follicles, mammary glands, salivary glands, and teeth. Despite varying in number, shape, and function, all these ectodermal organs develop through continuous and reciprocal epithelial–mesenchymal interactions, sharing common morphological and molecular features especially during their embryonic development. Diseases such as ectodermal dysplasias can affect simultaneously these organs, suggesting that they may arise from common multipotent precursors residing in the embryonic ectoderm. During embryogenesis, these putative ectodermal stem cells may adopt different fates and consequently be able to generate a variety of tissue-specific stem cells, which are the sources for the various cell lineages that form the diverse organs. The specification of those common epithelial precursors, as well as their further lineage commitment to tissue-specific stem cells, might be controlled by specific signals. It has been well documented that Notch, Wnt, bone morphogenetic protein, and fibroblast growth factor signaling pathways regulate cell fate decisions during the various stages of ectodermal organ development. However, the in vivo spatial and temporal dynamics of these signaling pathways are not yet well understood. Improving the current knowledge on the mechanisms involved in stem cell fate determination during organogenesis and homeostasis of ectodermal organs is crucial to develop effective stem cell-based therapies in order to regenerate or replace pathological and damaged tissues. PMID:22539926

  15. Nuclear magnetic resonance spectroscopy for determining the functional content of organic aerosols: A review

    International Nuclear Information System (INIS)

    Chalbot, Marie-Cecile G.; Kavouras, Ilias G.

    2014-01-01

    The knowledge deficit of organic aerosol (OA) composition has been identified as the most important factor limiting our understanding of the atmospheric fate and implications of aerosol. The efforts to chemically characterize OA include the increasing utilization of nuclear magnetic resonance spectroscopy (NMR). Since 1998, the functional composition of different types, sizes and fractions of OA has been studied with one-dimensional, two-dimensional and solid state proton and carbon-13 NMR. This led to the use of functional group ratios to reconcile the most important sources of OA, including secondary organic aerosol and initial source apportionment using positive matrix factorization. Future research efforts may be directed towards the optimization of experimental parameters, detailed NMR experiments and analysis by pattern recognition methods to identify the chemical components, determination of the NMR fingerprints of OA sources and solid state NMR to study the content of OA as a whole. - Highlights: • Organic aerosol composition by 1 H- and 13 C-NMR spectroscopy. • NMR fingerprints of specific sources, types and sizes of organic aerosol. • Source reconciliation and apportionment using NMR spectroscopy. • Research priorities towards understanding organic aerosol composition and origin. - This review presents the recent advances on the characterization of organic aerosol composition using nuclear magnetic resonance spectroscopy

  16. DETERMINATION OF MINERAL CONTAIN AND BACTERIA CONTAMINANT ON ORGANIC AND NONORGANIC FRESH VEGETABLES

    Directory of Open Access Journals (Sweden)

    Harsojo Harsojo

    2010-06-01

    Full Text Available The determination of mineral content and bacteria contaminant on fresh vegetable of long bean (Vegan ungulate Wall., white cabbage (Basic tolerance L., and lettuce (Lectuca sativa L. that cultivated by organic and nonorganic system have been done. The mineral content has been analyzed using neutron activation analysis and atomic absorption spectroscopy method, while bacteria contaminant by total plate count number using Nutrient Agar, Mac Conkey Agar, Baird Parker medium, and Salmonella using selective medium. The results showed that there are some essential mineral such as Fe, Zn, Ca, Co, and nonessential mineral Cd. There is tendency that fresh vegetable that cultivated by organic system contained Fe, Zn, Ca, Co and Cd mineral less than nonorganic. The Zn mineral content in nonorganic of fresh vegetable were higher than the limit of threshold number from Health Department, Republic of Indonesia (2004, while Cd mineral in organic or nonorganic of fresh vegetable were greater then threshold number from Codex Alimentarius Commision. The measurement of bacteria contaminant on organic and nonorganic of fresh vegetables contained aerob, coli, and Staphylococcus bacteria in organic of fresh vegetables were less compared to nonorganic of fresh vegetables.   Keywords: mineral, bacteria aerob, coli, Staphylococcus, Salmonella, organic, and nonorganic vegetable, neutron activation

  17. EVOLUTIONARY APPROACH TO DETERMINATION OF STRUCTURE OF TAX SYSTEM

    Directory of Open Access Journals (Sweden)

    Nathalie V. Yurchenkova

    2013-01-01

    Full Text Available Capacity of national tax systems isn’t fully revealed across all countries. Problems with tax administration, tax avoidance, leaving from the taxation of corporations and the leading financial organizations in the offshore confirm adaptation hypothesis stating that taxpayers adapt for changes in times quicker and more qualitatively than the state institutes. The leading role in formation of an evolutionary paradigm of the taxation belongs now to tools of evolutionary dynamics at social level.

  18. Organization Structure and Administrative Control: A Question of Dimensionality.

    Science.gov (United States)

    Montanari, John R.; Freedman, Sara M.

    1981-01-01

    Used a sample of national firms (N=836) to investigate the relationship between specialization, formalization, and centralization in the functional work unit. Data indicated that the three variables compose a single dimension of organizational structure. Another finding was that, within this dimension, specialization, formalization, and…

  19. Structure of Solvent-Free Nanoparticle−Organic Hybrid Materials

    KAUST Repository

    Yu, Hsiu-Yu; Koch, Donald L.

    2010-01-01

    that the constraint that each particle carries its own share of the fluid attached to itself yields a static structure factor that approaches zero as the wavenumber approaches zero. This result indicates that each particle excludes exactly one other particle from its

  20. Structure and membrane organization of photosystem II in green plants

    NARCIS (Netherlands)

    Hankamer, B; Barber, J; Boekema, EJ

    1997-01-01

    Photosystem II (PSII) is the pigment protein complex embedded in the thylakoid membrane of higher plants, algae, and cyanobacteria that uses solar energy to drive the photosynthetic water-splitting reaction. This chapter reviews the primary, secondary, tertiary, and quaternary structures of PSII as

  1. Structure, context, complexity, organization: physical aspects of information and value

    National Research Council Canada - National Science Library

    Eriksson, Karl-Erik; Lindgren, Kristian; Månsson, Bengt Å

    1987-01-01

    ... and of information theory are general enough to play such a role. The authors have been involved in studies of the handling of natural resources in human societies. There we met problems and ideas which led us to the theme of this book: a perspective and a set of concepts, useful for describing and understanding processes in which structure emerges. T...

  2. Determination of organic-matter content of Appalachian Devonian shales from gamma-ray logs

    International Nuclear Information System (INIS)

    Schmoker, J.W.

    1981-01-01

    The organic-matter content of the Devonian shale of the Appalachian basin is important for assessing the natural-gas resources of these rocks, and patterns of organic-matter distribution convey information on sedimentary processes and depositional environment. In most of the western part of the Appalachian basin the organic-matter content of the Devonian shale can be estimated from gamma-ray wire-line logs using the equation: phi 0 = (γ/sub B/ - γ)/1.378A, where phi 0 is the organic-matter content of the shale (fractional volume), γ the gamma-ray intensity (API units), γ/sub B/ the gamma-ray intensity if no organic matter is present (API units), and A the slope of the crossplot of gamma-ray intensity and formation density (API units/(g/cm 3 )). Organic-matter contents estimated using this equation are compared with organic-matter contents determined from direct laboratory analyses of organic carbon for 74 intervals of varying thickness from 12 widely separated wells. The organic-matter content of these intervals ranges from near zero to about 20% by volume. The gamma-ray intensity of the Cleveland Member of the Ohio Shale and the lower part of the Olentangy Shale is anomalously low compared to other Devonian shales of similar richness, so that organic-matter content computed for each of these units from gamma-ray logs is likely to be too low. Wire-line methods for estimating organic-matter content have the advantages of economy, readily available sources of data, and continuous sampling of the vertically heterogenous shale section. The gamma-ray log, in particular, is commonly run in the Devonian shale, its response characteristics are well known, and the cumulative pool of gamma-ray logs forms a large and geographically broad data base. The quantitative computation of organic-matter content from gamma-ray logs should be of practical value in studies of the Appalachian Devonian shale. 16 figures

  3. Organic light emission structures — XXI century technologies

    Directory of Open Access Journals (Sweden)

    Sorokin V. M.

    2009-02-01

    Full Text Available The given review allows to believe, that the decision of a complex technological, materialstechnological, technical problems at creation modern OLED- and PLED-devices in nearest 5—10 years will result in creation of devices with power efficiency more than 100 lm/W and service life till 100 000 hours. The realization of such parameters will allow to expand area of application of the considered systems and to create in the future unique flat powereffective organic lighting systems of new generation — light sources XXI of century.

  4. Hybrid organic-inorganic materials based on hydroxyapatite structure

    Energy Technology Data Exchange (ETDEWEB)

    Moussa, Sana Ben; Bachouâ, Hassen [U.R. Matériaux et synthèse organique UR17ES31, Institut Préparatoire aux Etudes d’Ingénieur de Monastir, Université de Monastir, 5019 Monastir (Tunisia); Gruselle, Michel, E-mail: michel.gruselle@upmc.fr [Sorbonne Université, UPMC Univ Paris 06, CNRS, UMR 8232, Institut Parisien de Chimie Moléculaire, F-75005 Paris (France); Beaunier, Patricia [Sorbonne Université, UPMC Univ Paris 06, CNRS, UMR 7197, Laboratoire de Réactivité de Surface, F-75005 Paris (France); Flambard, Alexandrine [Sorbonne Université, UPMC Univ Paris 06, CNRS, UMR 8232, Institut Parisien de Chimie Moléculaire, F-75005 Paris (France); Badraoui, Béchir [U.R. Matériaux et synthèse organique UR17ES31, Institut Préparatoire aux Etudes d’Ingénieur de Monastir, Université de Monastir, 5019 Monastir (Tunisia)

    2017-04-15

    The present article details the formation of calcium hydroxyapatite synthesized by the hydrothermal way, in presence of glycine or sarcosine. The presence of these amino-acids during the synthetic processes reduces the crystalline growthing through the formation of hybrid organic-inorganic species The crystallite sizes are decreasing and the morphology is modified with the increase of the amino-acid concentration. - Graphical abstract: Formation of Ca carboxylate salt leading to the grafting of glycine and sarcosine on the Ca=Hap surface (R= H, CH3).

  5. Insights into the fold organization of TIM barrel from interaction energy based structure networks.

    Science.gov (United States)

    Vijayabaskar, M S; Vishveshwara, Saraswathi

    2012-01-01

    There are many well-known examples of proteins with low sequence similarity, adopting the same structural fold. This aspect of sequence-structure relationship has been extensively studied both experimentally and theoretically, however with limited success. Most of the studies consider remote homology or "sequence conservation" as the basis for their understanding. Recently "interaction energy" based network formalism (Protein Energy Networks (PENs)) was developed to understand the determinants of protein structures. In this paper we have used these PENs to investigate the common non-covalent interactions and their collective features which stabilize the TIM barrel fold. We have also developed a method of aligning PENs in order to understand the spatial conservation of interactions in the fold. We have identified key common interactions responsible for the conservation of the TIM fold, despite high sequence dissimilarity. For instance, the central beta barrel of the TIM fold is stabilized by long-range high energy electrostatic interactions and low-energy contiguous vdW interactions in certain families. The other interfaces like the helix-sheet or the helix-helix seem to be devoid of any high energy conserved interactions. Conserved interactions in the loop regions around the catalytic site of the TIM fold have also been identified, pointing out their significance in both structural and functional evolution. Based on these investigations, we have developed a novel network based phylogenetic analysis for remote homologues, which can perform better than sequence based phylogeny. Such an analysis is more meaningful from both structural and functional evolutionary perspective. We believe that the information obtained through the "interaction conservation" viewpoint and the subsequently developed method of structure network alignment, can shed new light in the fields of fold organization and de novo computational protein design.

  6. Microvessel organization and structure in experimental brain tumors: microvessel populations with distinctive structural and functional properties.

    Science.gov (United States)

    Schlageter, K E; Molnar, P; Lapin, G D; Groothuis, D R

    1999-11-01

    We studied microvessel organization in five brain tumor models (ENU, MSV, RG-2, S635cl15, and D-54MG) and normal brain, including microvessel diameter (LMVD), intermicrovessel distance (IMVD), microvessel density (MVD), surface area (S(v)), and orientation. LMVD and IMVD were larger and MVD was lower in tumors than normal brain. S(v) in tumors overlapped normal brain values and orientation was random in both tumors and brain. ENU and RG-2 tumors and brain were studied by electron microscopy. Tumor microvessel wall was thicker than that of brain. ENU and normal brain microvessels were continuous and nonfenestrated. RG-2 microvessels contained fenestrations and endothelial gaps; the latter had a maximum major axis of 3.0 microm. Based on anatomic measurements, the pore area of RG-2 tumors was estimated at 7.4 x 10(-6) cm(2) g(-1) from fenestrations and 3.5 x 10(-5) cm(2) g(-1) from endothelial gaps. Increased permeability of RG-2 microvessels to macromolecules is most likely attributable to endothelial gaps. Three microvessel populations may occur in brain tumors: (1) continuous nonfenestrated, (2) continuous fenestrated, and (3) discontinuous (with or without fenestrations). The first group may be unique to brain tumors; the latter two are similar to microvessels found in systemic tumors. Since structure-function properties of brain tumor microvessels will affect drug delivery, studies of microvessel function should be incorporated into clinical trials of brain tumor therapy, especially those using macromolecules. Copyright 1999 Academic Press.

  7. [Organization of clinical emergency units. Mission and environmental factors determine the organizational concept].

    Science.gov (United States)

    Genewein, U; Jakob, M; Bingisser, R; Burla, S; Heberer, M

    2009-02-01

    Mission and organization of emergency units were analysed to understand the underlying principles and concepts. The recent literature (2000-2007) on organizational structures and functional concepts of clinical emergency units was reviewed. An organizational portfolio based on the criteria specialization (presence of medical specialists on the emergency unit) and integration (integration of the emergency unit into the hospital structure) was established. The resulting organizational archetypes were comparatively assessed based on established efficiency criteria (efficiency of resource utilization, process efficiency, market efficiency). Clinical emergency units differ with regard to autonomy (within the hospital structure), range of services and service depth (horizontal and vertical integration). The "specialization"-"integration"-portfolio enabled the definition of typical organizational patterns (so-called archetypes): profit centres primarily driven by economic objectives, service centres operating on the basis of agreements with the hospital board, functional clinical units integrated into medical specialty units (e.g., surgery, gynaecology) and modular organizations characterized by small emergency teams that would call specialists immediately after triage and initial diagnostic. There is no "one fits all" concept for the organization of clinical emergency units. Instead, a number of well characterized organizational concepts are available enabling a rational choice based on a hospital's mission and demand.

  8. Flexible organic solar cells including efficiency enhancing grating structures

    International Nuclear Information System (INIS)

    De Oliveira Hansen, Roana Melina; Liu Yinghui; Madsen, Morten; Rubahn, Horst-Günter

    2013-01-01

    In this work, a new method for the fabrication of organic solar cells containing functional light-trapping nanostructures on flexible substrates is presented. Polyimide is spin-coated on silicon support substrates, enabling standard micro- and nanotechnology fabrication techniques, such as photolithography and electron-beam lithography, besides the steps required for the bulk-heterojunction organic solar cell fabrication. After the production steps, the solar cells on polyimide are peeled off the silicon support substrates, resulting in flexible devices containing nanostructures for light absorption enhancement. Since the solar cells avoid using brittle electrodes, the performance of the flexible devices is not affected by the peeling process. We have investigated three different nanostructured grating designs and conclude that gratings with a 500 nm pitch distance have the highest light-trapping efficiency for the selected active layer material (P3HT:PCBM), resulting in an enhancement of about 34% on the solar cell efficiency. The presented method can be applied to a large variety of flexible nanostructured devices in future applications. (paper)

  9. Perceptual organization in computer vision - A review and a proposal for a classificatory structure

    Science.gov (United States)

    Sarkar, Sudeep; Boyer, Kim L.

    1993-01-01

    The evolution of perceptual organization in biological vision, and its necessity in advanced computer vision systems, arises from the characteristic that perception, the extraction of meaning from sensory input, is an intelligent process. This is particularly so for high order organisms and, analogically, for more sophisticated computational models. The role of perceptual organization in computer vision systems is explored. This is done from four vantage points. First, a brief history of perceptual organization research in both humans and computer vision is offered. Next, a classificatory structure in which to cast perceptual organization research to clarify both the nomenclature and the relationships among the many contributions is proposed. Thirdly, the perceptual organization work in computer vision in the context of this classificatory structure is reviewed. Finally, the array of computational techniques applied to perceptual organization problems in computer vision is surveyed.

  10. Organizations Utilize Lateral Relationships

    OpenAIRE

    Jacqueline C.

    2017-01-01

    The structures that subscribe to different organization play a major role and determine how information flows throughout an organization as well as the reporting structure within the organization. In some organization, decision making rely with the top management, and in other organizations, decision making responsibilities may be distributed within the organization. The latter part is what mainly constitutes a lateral structural arrangement where various departments work hand in hand in achi...

  11. Structural Determinants of Specific Lipid Binding to Potassium Channels

    NARCIS (Netherlands)

    Weingarth, M.H.|info:eu-repo/dai/nl/330985655; Prokofyev, A.; van der Cruijsen, E.A.W.|info:eu-repo/dai/nl/330826743; Nand, D.|info:eu-repo/dai/nl/337731403; Bonvin, A.M.J.J.|info:eu-repo/dai/nl/113691238; Pongs, O.; Baldus, M.|info:eu-repo/dai/nl/314410864

    2013-01-01

    We have investigated specific lipid binding to the pore domain of potassium channels KcsA and chimeric KcsAKv1.3 on the structural and functional level using extensive coarse-grained and atomistic molecular dynamics simulations, solid-state NMR, and single channel measurements. We show that, while

  12. Ab initio structure determination via powder X-ray diffraction

    Indian Academy of Sciences (India)

    Unknown

    Although the method of structure completion when once the starting model is provided is ... In this article a survey of the recent development in this area is ..... The Monte Carlo method 4,9 differs from the traditional approaches as it operates in.

  13. Type of disturbance and ecological history determine structural stability.

    NARCIS (Netherlands)

    van der Wurff, A.W.G.; Kools, S.A.E.; Boivin, M.E.; van den Brink, P.J.; van den Megen, H.H.M.; Riksen, J.A.G.; Doroszuk, A.; Kammenga, J.E.

    2007-01-01

    This study aims to reveal whether complexity, namely, community and trophic structure, of chronically stressed soil systems is at increased risk or remains stable when confronted with a subsequent disturbance. Therefore, we focused on a grassland with a history of four centuries of patchy

  14. Type of disturbance and ecological history determine structural stability

    NARCIS (Netherlands)

    Wurff, van der A.W.G.; Kools, S.A.E.; Boivin, M.E.Y.; Brink, van den P.J.; Megen, van H.H.B.; Riksen, J.A.G.; Doroszuk, A.; Kammenga, J.E.

    2007-01-01

    This study aims to reveal whether complexity, namely, community and trophic structure, of chronically stressed soil systems is at increased risk or remains stable when confronted with a subsequent disturbance. Therefore, we focused on a grassland with a history of four centuries of patchy

  15. Thermal effect on structure organizations in cobalt-fullerene nanocomposition.

    Science.gov (United States)

    Lavrentiev, Vasily; Vacik, Jiri; Naramoto, Hiroshi; Sakai, Seiji

    2010-04-01

    Effect of deposition temperature (Ts) on structure of Co-C60 nanocomposite (NC) prepared by simultaneous deposition of cobalt and fullerene on sapphire is presented. The NC structure variations with Ts increasing from room temperature (RT) to 400 degrees C have been analyzed using scanning electron microscopy (SEM), atomic force microscopy (AFM) and Raman spectroscopy. AFM and SEM show granule-like structure of the Co-C60 film. The mixture film deposited at RT includes the hills on the surface suggesting accumulation of internal stress during phase separation. Raman spectra show 25 cm(-1) downshift of Ag(2) C60 peak suggesting -Co-C60- polymerization in C60-based matrix of the NC film. Analysis of Raman spectra has revealed existence of amorphous carbon (a-C) in the NC matrix that argues C60 decomposition. The Ts increase to 200 degrees C causes the surface hills smoothing. In parallel, downshift of the Ag(2) peak decreases to 16 cm(-1) that implies more pronounced phase separation and lower -Co-C60- polymerization efficiency. Also, amount of a-C content slightly increases. Further Ts increasing to 400 degrees C changes the NC structure dramatically. AFM shows evident enlargement of the granules. According to Raman spectra the high Ts deposition yields pronounced C60 decomposition increasing the a-C content. Features of a-C Raman peak imply nucleation of graphitic islands at the NC interfaces. Abundant decomposition of C60 in the mixture film deposited at 400 degrees C is referred to cobalt catalytic effect.

  16. Organic Waste Composts, a Serious Rare- Earth Source as Determined by Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Sroor, A.; El-Bahi, S.M.; Abdel-Halieem, A.S.; Abdel-Sabour, M.F.

    1999-01-01

    Delayed Neutron Activation Analysis technique [DNNA] was applied for investigating rare-earth elements and some heavy metals content of some locally organic fertilizers namely cattle manure (CM) , dried sewage sludge [SS] , municipal solid waste [MSW] and mixture for a (SS+MSW). The γ-ray spectrum of each sample was investigated using a HPGe detector equipped with computer unit. Fourteen elements were determined. Some of them were confirmed by the γ-γ cascades using a HPGe-HPGe coincidence spectrometer. The concentration of these elements in each sample was measured in μg/g. Some of these elements may lead to undesirable environmental effects. The undiscriminating use of organic waste as organic fertilizers may result in the increase of toxic elements [Cr, Sc, Sb, Th, etc.) in soil environment which may transfer through food chain to human health

  17. The relationship between family orientation, organization context, organization structure and firm performance

    NARCIS (Netherlands)

    Meijaard, J.; Uhlaner, L.M.

    2004-01-01

    This study focuses on the prediction of three firm performance indicators, sales growth, innovation performance and profitability, on a sample of small and medium-sized firms in the Netherlands. Predictions from agency theory and the resource based view of organizations lead to alternate hypotheses

  18. Modeling of self-organization of two-dimensional ordered structures

    Energy Technology Data Exchange (ETDEWEB)

    Egorov, V V; Garmay, Y P; Shaldzhyan, A A; Vasin, A V; Kiselev, O I [Research Institute of Influenza of the Ministry of Health and Social Development of the Russian Federation, Prof. Popova st. 15/17, St-Petersburg (Russian Federation); Lebedev, D V [Department of Molecular and Radiation Biophysics Petersburg Nuclear Physics Institute of the Russian Academy of Science, Orlova Roscha, Gatchina, Leningrad Region (Russian Federation); Grudinina, N A, E-mail: toizeg@gmail.com [Institute of Experimental Medicine, North-Western Branch of the Russian Academy of Medical Science, 12, Akademika Pavlova st., St-Petersburg (Russian Federation)

    2011-04-01

    The problem of the search of biostructures capable to self-organization is quite urgent considering the prospects of application of nanostructured biomaterials as components of composite materials in transplantology and optics as well as 'scaffolds' for the synthesis of nanostructured materials based on inorganic particles. The given study focuses on modeling of the growth of structures using the cellular automata with a set of states of the two values (0 and 1), with the value corresponding to the state is determined by the contribution of 'the closest neighbor' (by the probability of induction of the state of the nextgeneration in the direction of the interaction) and the geometry of the field isdetermined by the vector of the direction of the particle and the direction of the interaction.

  19. The method for determination of parameters of the phenomenological continual model of soil organic matter transformation

    Directory of Open Access Journals (Sweden)

    S. I. Bartsev

    2015-06-01

    Full Text Available A possible method for experimental determination of parameters of the previously proposed continual mathematical model of soil organic matter transformation is theoretically considered in this paper. The previously proposed by the authors continual model of soil organic matter transformation, based on using the rate of matter transformation as a continual scale of its recalcitrance, describes the transformation process phenomenologically without going into detail of microbiological mechanisms of transformation. Thereby simplicity of the model is achieved. The model is represented in form of one differential equation in first­order partial derivatives, which has an analytical solution in elementary functions. The model equation contains a small number of empirical parameters which generally characterize environmental conditions where the matter transformation process occurs and initial properties of the plant litter. Given the values of these parameters, it is possible to calculate dynamics of soil organic matter stocks and its distribution over transformation rate. In the present study, possible approaches for determination of the model parameters are considered and a simple method of their experimental measurement is proposed. An experiment of an incubation of chemically homogeneous samples in soil and multiple sequential measurement of the sample mass loss with time is proposed. An equation of time dynamics of mass loss of incubated homogeneous sample is derived from the basic assumption of the presented soil organic matter transformation model. Thus, fitting by the least squares method the parameters of sample mass loss curve calculated according the proposed mass loss dynamics equation allows to determine the parameters of the general equation of soil organic transformation model.

  20. Method development for the determination of volatile organic compounds in mixed waste

    International Nuclear Information System (INIS)

    Sandoval, W.F.; Rogers, Y.C.; Schappert, M.F.; Boland, K.S.; Spall, W.D.; Wilkerson, C.W. Jr.

    1993-01-01

    While analytical methods exist for the determination of Resource Conservation and Recovery Act (RCRA) listed organic and inorganic compounds in hazardous materials, equivalent methods suitable for the characterization of radioactively contaminated samples are not at the same level of maturity. The Mixed Waste Methods Development Lab. has been established at Los Alamos National Lab. to address the need for such procedures. This presentation will focus on the efforts that have been directed toward the determination of volatile organic compounds (VOCs) in mixed waste matrices. The capabilities of the Mixed Waste Methods Development Lab. will be outlined. Modifications to the containment boxes and analytical instrumentation required for the analyses will be described, as will experimental procedures and system performance benchmarks. Preliminary results from surrogate and real mixed waste matrices will be presented, and future directions for our method development effort will be discussed

  1. Organic tank safety project: Equilibrium moisture determination task. FY 1998 annual progress report

    International Nuclear Information System (INIS)

    Scheele, R.D.; Bredt, P.R.; Sell, R.L.

    1998-08-01

    During fiscal year 1998, PNNL investigated the effect of P H 2 O at or near maximum tank waste surface temperatures on the equilibrium water content of selected Hanford waste samples. These studies were performed to determine how dry organic-bearing wastes will become if exposed to environmental Hanford water partial pressures. The samples tested were obtained from Organic Watch List Tanks. At 26 C, the lowest temperature used, the water partial pressures ranged from 2 to 22 torr. At 41 C, the highest temperature used, the water partial pressures ranged from 3.5 to 48 torr. When the aliquots exposed to the lowest and highest water partial pressures reached their equilibrium or near-equilibrium water contents, they were exchanged to determine if hysteresis occurred. In some experiments, once equilibrated, aliquots not used in the hysteresis experiments were allowed to equilibrate at room temperature (23 C) until the hysteresis experiments ended; this provides a measure of the effect of temperature

  2. Study of a spectrophotometric method of plutonium determination in the organic phase

    International Nuclear Information System (INIS)

    Brutus, Andre

    1971-03-01

    The aim of this paper is to study a method of determining plutonium in the 'Purex' process organic phase, the minimum concentrations to be measured being about 10 -5 M. Spectrophotometry, at 665 nm, of the plutonium arsenazo III complex was carried out directly in the organic phase. Several complexes can be formed between arsenazo III and plutonium; the conditions under which a single complex is obtained, and also those for which this latter follows Beer's law, were determined. The nature and stability of the complex formed were studied, after which it was possible to calculate the equilibrium constant and the standard free enthalpy variation. The field application of the method was established from calculation of the regression line, the confidence limits, the detection limit and the sensitivity. Finally the principle of the elimination of certain troublesome cations in the medium involved was considered. (author) [fr

  3. Determinants of Shift Work impacting Job Satisfaction: A study on Service Sector Organizations in Pakistan

    Directory of Open Access Journals (Sweden)

    Wasim Abbas Awan

    2013-10-01

    Full Text Available This study aims to investigate the impact of determinants of shift work on job satisfaction in service sector organizations of Pakistan. History reveals that the invention of Thomas Edison brought the change in working environment and industrial revolution results in the birth of shift works. A great number of theories in Management are there to define Job satisfaction. All of them show the relationship between ability to perform and the productivity. In order to investigate their impact descriptive study is taken in to account in which survey research method is used to collect data. On the basis of quantitative analysis this study reveals that determinants of shift work has positive impact on job satisfaction. Finally recommendations are made to increase shift work in service sector organizations of Pakistan so that people may upraise their standards of living.

  4. Structure of the Buried Metal-Molecule Interface in Organic Thin Film Devices

    DEFF Research Database (Denmark)

    Hansen, Christian Rein; Sørensen, Thomas Just; Glyvradal, Magni

    2009-01-01

    By use of specular X-ray reflectivity (XR) the structure of a metal-covered organic thin film device is measured with angstrom resolution. The model system is a Langmuir-Blodgett (LB) film, sandwiched between a silicon substrate and a top electrode consisting of 25 Å titanium and 100 Å aluminum....... By comparison of XR data for the five-layer Pb2+ arachidate LB film before and after vapor deposition of the Ti/Al top electrode, a detailed account of the structural damage to the organic film at the buried metal-molecule interface is obtained. We find that the organized structure of the two topmost LB layers...

  5. Experimental research on the structural characteristics of high organic soft soil in different deposition ages

    Science.gov (United States)

    Liu, Fei; Lin, Guo-he

    2018-03-01

    High organic soft soil, which is distributed at Ji Lin province in China, has been studied by a lot of scholars. In the paper, structural characteristics with different deposition ages have been researched by experimental tests. Firstly, the characteristics of deposition age, degree of decompositon, high-pressure consolidation and microstructure have been measured by a series of tests. Secondly, structural strengths which were deposited in different ages, have been carried out to test the significant differences of stress-strain relations between remoulded and undisturbed high organic soft soil samples. Results showed that high organic soft soil which is deposited at different ages will influence its structural characteristics.

  6. [Structural organization of 5S ribosomal DNA of Rosa rugosa].

    Science.gov (United States)

    Tynkevych, Iu O; Volkov, R A

    2014-01-01

    In order to clarify molecular organization of the genomic region encoding 5S rRNA in diploid species Rosa rugosa several 5S rDNA repeated units were cloned and sequenced. Analysis of the obtained sequences revealed that only one length variant of 5S rDNA repeated units, which contains intact promoter elements in the intergenic spacer region (IGS) and appears to be transcriptionally active is present in the genome. Additionally, a limited number of 5S rDNA pseudogenes lacking a portion of coding sequence and the complete IGS was detected. A high level of sequence similarity (from 93.7 to 97.5%) between the IGS of major 5S rDNA variants of East Asian R. rugosa and North American R. nitida was found indicating comparatively recent divergence of these species.

  7. Organization structure and the performance of hospital emergency services.

    Science.gov (United States)

    Georgopoulos, B S

    1985-07-01

    A comparative study of 30 hospital emergency departments (EDs) and nearly 1,500 individuals associated with them was conducted. Data were obtained from institutional records, physicians, patients, and other sources. The object was to investigate the relationship between the organization and performance of these health service systems. The study assessed the quality of medical care, the quality of nursing care, and the economic efficiency of hospital EDs. The results show substantial interinstitutional differences in these criteria. They also show a significant relationship between medical and nursing care, but not between the quality of care and economic efficiency. Differences in ED performance are related to medical staffing patterns, medical teaching affiliation, personnel training, scope of emergency services, number of patient visits processed, and hospital size and complexity. Not all of these variables, however, correlate positively with all three criteria of performance, nor are they equally important to each.

  8. Structural organization of the human and mouse laminin beta2 chain genes, and alternative splicing at the 5' end of the human transcript

    DEFF Research Database (Denmark)

    Durkin, M E; Gautam, M; Loechel, F

    1996-01-01

    We have determined the structural organization of the human and mouse genes that encode the laminin beta2 chain (s-laminin), an essential component of the basement membranes of the neuromuscular synapse and the kidney glomerulus. The human and mouse genes have a nearly identical exon-intron organ......We have determined the structural organization of the human and mouse genes that encode the laminin beta2 chain (s-laminin), an essential component of the basement membranes of the neuromuscular synapse and the kidney glomerulus. The human and mouse genes have a nearly identical exon...

  9. {sup 18}O/{sup 16}O determination in organic matter

    Energy Technology Data Exchange (ETDEWEB)

    Saurer, M.; Siegwolf, R. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    The oxygen isotope ratio in plant material can be used to deduce information about the climate and the environment. We present a simple and fast continuous-flow technique for the determination of the {sup 18}O/{sup 16}O ratio in organic matter. In this method the samples are thermally decomposed in the presence of glassy carbon and the evolving monoxide is used to determine the oxygen ratio. Not only cellulose but also nitrogen-containing materials can be processed when interfering gases (mainly N{sub 2}) are separated from CO by gas chromatography. (author) 2 figs., 2 refs.

  10. Passive Dosing to Determine the Speciation of Hydrophobic Organic Chemicals in Aqueous Samples

    DEFF Research Database (Denmark)

    Birch, Heidi; Gouliarmou, V.; Lützhøft, Hans-Christian Holten

    2010-01-01

    A new analytical approach to determine the speciation of hydrophobic organic analytes is presented. The freely dissolved concentration in a sample is controlled by passive dosing from silicone (poly(dimethylsiloxane)), and the total sample concentration at equilibrium is measured. The free fraction...... is determined as the ratio between measured concentrations in pure water and sample. C-14-labeled fluoranthene served as model analyte, and total sample concentrations were easily measured by liquid scintillation counting. The method was applied to surface water, stormwater runoff, and wastewater...... (SPME). This analytical approach combines simplicity with high precision, and it does not require any phase separation steps....

  11. Determinants of Shift Work impacting Job Satisfaction: A study on Service Sector Organizations in Pakistan

    OpenAIRE

    Wasim Abbas Awan

    2013-01-01

    This study aims to investigate the impact of determinants of shift work on job satisfaction in service sector organizations of Pakistan. History reveals that the invention of Thomas Edison brought the change in working environment and industrial revolution results in the birth of shift works. A great number of theories in Management are there to define Job satisfaction. All of them show the relationship between ability to perform and the productivity. In order to investigate their impact d...

  12. Determination of Velocity And Acceleration of Structural Deformation ...

    African Journals Online (AJOL)

    This paper outlines the procedure of geodetic monitoring system of circular oil storage ... In this study, only tank 6 was used as case study scenario for the determination of ... In this study, deformation analysis by Kalman Filter technique of the ...

  13. Gap-closing test structures for temperature budget determination

    NARCIS (Netherlands)

    Faber, Erik Jouwert; Wolters, Robertus A.M.; Schmitz, Jurriaan

    2011-01-01

    We present the extension of a method for determining the temperature budget of the process side of silicon substrates and chips, employing silicide formation reactions. In this work, silicon-on-insulator type substrates are used instead of bulk silicon wafers. By an appropriate choice of the layer

  14. Structure determination of T-cell protein-tyrosine phosphatase

    DEFF Research Database (Denmark)

    Iversen, L.F.; Møller, K. B.; Pedersen, A.K.

    2002-01-01

    Protein-tyrosine phosphatase 1B (PTP1B) has recently received much attention as a potential drug target in type 2 diabetes. This has in particular been spurred by the finding that PTP1B knockout mice show increased insulin sensitivity and resistance to diet-induced obesity. Surprisingly, the highly...... homologous T cell protein-tyrosine phosphatase (TC-PTP) has received much less attention, and no x-ray structure has been provided. We have previously co-crystallized PTP1B with a number of low molecular weight inhibitors that inhibit TC-PTP with similar efficiency. Unexpectedly, we were not able to co...... the high degree of functional and structural similarity between TC-PTP and PTP1B, we have been able to identify areas close to the active site that might be addressed to develop selective inhibitors of each enzyme....

  15. Advances in RNA Structure Determination | Center for Cancer Research

    Science.gov (United States)

    The recent years have witnessed a revolution in the field of RNA structure and function. Until recently the main contribution of RNA in cellular and disease functions was considered to be a role defined by the central dogma, namely DNA codes for mRNAs, which in turn encode for proteins, a notion facilitated by non-coding ribosomal RNA and tRNA. It was also assumed at the time

  16. Determinants of fish assemblage structure in Northwestern Great Plains streams

    Science.gov (United States)

    Mullen, J.A.; Bramblett, R.G.; Guy, C.S.; Zale, A.V.; Roberts, D.W.

    2011-01-01

    Prairie streams are known for their harsh and stochastic physical conditions, and the fish assemblages therein have been shown to be temporally variable. We assessed the spatial and temporal variation in fish assemblage structure in five intermittent, adventitious northwestern Great Plains streams representing a gradient of watershed areas. Fish assemblages and abiotic conditions varied more spatially than temporally. The most important variables explaining fish assemblage structure were longitudinal position and the proportion of fine substrates. The proportion of fine substrates increased proceeding upstream, approaching 100% in all five streams, and species richness declined upstream with increasing fine substrates. High levels of fine substrate in the upper reaches appeared to limit the distribution of obligate lithophilic fish species to reaches further downstream. Species richness and substrates were similar among all five streams at the lowermost and uppermost sites. However, in the middle reaches, species richness increased, the amount of fine substrate decreased, and connectivity increased as watershed area increased. Season and some dimensions of habitat (including thalweg depth, absolute distance to the main-stem river, and watershed size) were not essential in explaining the variation in fish assemblages. Fish species richness varied more temporally than overall fish assemblage structure did because common species were consistently abundant across seasons, whereas rare species were sometimes absent or perhaps not detected by sampling. The similarity in our results among five streams varying in watershed size and those from other studies supports the generalization that spatial variation exceeds temporal variation in the fish assemblages of prairie and warmwater streams. Furthermore, given longitudinal position, substrate, and stream size, general predictions regarding fish assemblage structure and function in prairie streams are possible. ?? American

  17. The internal structure of magnetic nanoparticles determines the magnetic response

    Czech Academy of Sciences Publication Activity Database

    Pacáková, Barbara; Kubíčková, Simona; Salas, G.; Mantlíková, Alice; Marciello, M.; Morales, M.P.; Nižňanský, D.; Vejpravová, Jana

    2017-01-01

    Roč. 9, č. 16 (2017), s. 5129-5140 ISSN 2040-3364 R&D Projects: GA ČR(CZ) GA15-01953S Institutional support: RVO:68378271 Keywords : nanoparticles * single-domain * internal structure Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 7.367, year: 2016

  18. Structural similarity image quality reliability: Determining parameters and window size

    OpenAIRE

    Silvestre-Blanes, Javier

    2011-01-01

    The need to obtain objective values of the quality of distorted images with respect to the original is fundamental in multimedia and image processing applications. It is generally required that this value correlates well with the human vision system (HVS). In spite of the properties and the general use of the mean square error (MSE) measurement, this has a poor correlation with HSV, which has led to the development of methods such as structural similarity (SSIM). This metric improves the corr...

  19. Determination of the pion and kaon structure functions

    International Nuclear Information System (INIS)

    Aitkenhead, W.; Barton, D.S.; Brandenburg, G.W.; Busza, W.; Dobrowolski, T.; Friedman, J.I.; Kendall, H.W.; Lyons, T.; Nelson, B.; Rosenson, L.; Toy, W.; Verdier, R.; Votta, L.; Chiaradia, M.T.; DeMarzo, C.; Favuzzi, C.; Germinario, G.; Guerriero, L.; LaVopa, P.; Maggi, G.; Posa, F.; Selvaggi, G.; Spinelli, P.; Waldner, F.; Brenner, A.E.; Carey, D.C.; Elias, J.E.; Garbincius, P.H.; Mikenberg, G.; Polychronakos, V.A.; Meunier, R.; Cutts, D.; Dulude, R.S.; Lanou, R.E. Jr.; Massimo, J.T.

    1980-01-01

    Quark structure functions have been extracted from low-p/sub T/ inclusive hadron production data for the pion and kaon with use of the recombination model. n/sup π/=1.0 +- 0.1 and n/sup K/=2.5 +- 0.6 is obtained, where n is the leading (1-x) power of the nonstrange--valence-quark distribution. Both the pion and kaon nonstrange--sea-quark functions have napprox. =3.5

  20. Entry Regulations, Product Differentiation and Determinants of Market Structure

    OpenAIRE

    Maican, Florin; Orth, ´Matilda

    2013-01-01

    We use a dynamic oligopoly model of entry and exit to evaluate how entry regulations affect profitability and market structure in retail. The model incorporates demand and store-level heterogeneity. Based on unique data for all retail food stores in Sweden, we find that the average entry costs for small and large stores are 10 and 18 percent lower, respectively, in markets with liberal compared with restrictive regulations. Counterfactual simulations show that lower entry costs in restrictive...

  1. Entry regulations, welfare and determinants of market structure

    OpenAIRE

    Maican, Florin; Orth, Matilda

    2015-01-01

    We use a dynamic oligopoly model of entry and exit with store-type differentiation to evaluate how entry regulations affect profitability, market structure and welfare. Based on unique data for all retail food stores in Sweden, we estimate demand, recover variable profits, and estimate entry costs and fixed costs by store type. Counterfactual policy experiments show that welfare increases when competition is enhanced by lower entry costs. Protecting small stores by imposing licensing fees on ...

  2. Structural change of Japan's nuclear R and D organization

    International Nuclear Information System (INIS)

    Yoon, S. W.; Jeong, H. S.; Lee, T. Z.

    2002-01-01

    Recently Japanese government is performing a reform work in order to solve the problem involved the existing Special Public Institutions. As results to, JAERI and JNC will be merged into a new independent administrative institution which will be expected to Japan's nuclear policy effectively. Henceforth, government of Japan will establish the legislation and organizational structure until 2005. From the finding of this case study, we should make an effort in order to carry out Korea's nuclear R and D effectively for the strengthening of national competitive

  3. [Structure and functional organization of integrated cardiac intensive care].

    Science.gov (United States)

    Scherillo, Marino; Miceli, Domenico; Tubaro, Marco; Guiducci, Umberto

    2007-05-01

    The early invasive strategy for the treatment of acute coronary syndromes and the increasing number of older and sicker patients requiring prolonged and more complex intensive care have induced many changes in the function of the intensive care units. These changes include the statement that specially trained cardiologists and cardiac nurses who can manage patients with acute cardiac conditions should staff the intensive care units. This document indicates the structure of the units and specific recommendations for the number of beds, monitoring system, respirators, pacemaker/defibrillators and additional equipment.

  4. Using self-organizing maps to determine observation threshold limit predictions in highly variant data

    Science.gov (United States)

    Paganoni, C.A.; Chang, K.C.; Robblee, M.B.

    2006-01-01

    A significant data quality challenge for highly variant systems surrounds the limited ability to quantify operationally reasonable limits on the data elements being collected and provide reasonable threshold predictions. In many instances, the number of influences that drive a resulting value or operational range is too large to enable physical sampling for each influencer, or is too complicated to accurately model in an explicit simulation. An alternative method to determine reasonable observation thresholds is to employ an automation algorithm that would emulate a human analyst visually inspecting data for limits. Using the visualization technique of self-organizing maps (SOM) on data having poorly understood relationships, a methodology for determining threshold limits was developed. To illustrate this approach, analysis of environmental influences that drive the abundance of a target indicator species (the pink shrimp, Farfantepenaeus duorarum) provided a real example of applicability. The relationship between salinity and temperature and abundance of F. duorarum is well documented, but the effect of changes in water quality upstream on pink shrimp abundance is not well understood. The highly variant nature surrounding catch of a specific number of organisms in the wild, and the data available from up-stream hydrology measures for salinity and temperature, made this an ideal candidate for the approach to provide a determination about the influence of changes in hydrology on populations of organisms.

  5. Direct determination of triplet phases and enantiomorphs of non-centrosymmetric structures. Pt. 2

    International Nuclear Information System (INIS)

    Huemmer, K.; Weckert, E.; Bondza, H.

    1989-01-01

    Direct measurements of triplet phase relationships for non-centrosymmetric light-atom organic structures with medium-size unit cells are reported. The phase information can be extracted from the three-beam profiles of a Renninger ψ-scan experiment. The measurements were carried out with a special ψ-circle diffractometer installed on a rotating Cu-anode generator. The incident-beam divergence is reduced to 0.02 0 . The experimental results confirm the theoretical considerations of paper I of this work. As triplet phases of ±90 0 can be distinguished, the absolute structure can be determined unambiguously. The measurements show that the triplet-phase-dependent interference effects may be superposed on phase-independent Umweganregung or Aufhellung effects. By a comparison of the ψ-scan profiles of two centrosymmetrically related three-beam cases, the triplet phases of which have opposite signs, it is possible to evaluate the phase-independent effects and to determine the value of the triplet phase with an accuracy of at least 90 0 . (orig.)

  6. Interlaboratory study of a method for determining nonvolatile organic carbon in aquifer materials

    Science.gov (United States)

    Caughey, M.E.; Barcelona, M.J.; Powell, R.M.; Cahill, R.A.; Gron, C.; Lawrenz, D.; Meschi, P.L.

    1995-01-01

    The organic carbon fraction in aquifer materials exerts a major influence on the subsurface mobilities of organic and organic-associated contaminants. The spatial distribution of total organic carbon (TOC) in aquifer materials must be determined before the transport of hydrophobic organic pollutants in aquifers can be modeled accurately. Previous interlaboratory studies showed that it is difficult to measure TOC concentrations 1%. We have tested a new analytical method designed to improve the accuracy and precision of nonvolatile TOC quantitation in geologic materials that also contain carbonate minerals. Four authentic aquifer materials and one NIST standard reference material were selected as test materials for a blind collaborative study. Nonvolatile TOC in these materials ranged from 0.05 to 1.4%, while TIC ranged from 0.46 to 12.6%. Sample replicates were digested with sulfurous acid, dried at 40??C, and then combusted at 950??C using LECO or UIC instruments. For the three test materials that contained >2% TIC, incomplete acidification resulted in a systematic positive bias of TOC values reported by five of the six laboratories that used the test method. Participants did not have enough time to become proficient with the new method before they analyzed the test materials. A seventh laboratory successfully used an alternative method that analyzed separate liquid and solid fractions of the acidified sample residues. ?? 1995 Springer-Verlag.

  7. Interfacial self-organization of bolaamphiphiles bearing mesogenic groups: relationships between the molecular structures and their self-organized morphologies.

    Science.gov (United States)

    Song, Bo; Liu, Guanqing; Xu, Rui; Yin, Shouchun; Wang, Zhiqiang; Zhang, Xi

    2008-04-15

    This article discusses the relationship between the molecular structure of bolaamphiphiles bearing mesogenic groups and their interfacial self-organized morphology. On the basis of the molecular structures of bolaamphiphiles, we designed and synthesized a series of molecules with different hydrophobic alkyl chain lengths, hydrophilic headgroups, mesogenic groups, and connectors between the alkyl chains and the mesogenic group. Through investigating their interfacial self-organization behavior, some experiential rules are summarized: (1) An appropriate alkyl chain length is necessary to form stable surface micelles; (2) different categories of headgroups have a great effect on the interfacial self-organized morphology; (3) different types of mesogenic groups have little effect on the structure of the interfacial assembly when it is changed from biphenyl to azobenzene or stilbene; (4) the orientation of the ester linker between the mesogenic group and alkyl chain can greatly influence the interfacial self-organization behavior. It is anticipated that this line of research may be helpful for the molecular engineering of bolaamphiphiles to form tailor-made morphologies.

  8. Persistence of urban organic aerosols composition: Decoding their structural complexity and seasonal variability

    International Nuclear Information System (INIS)

    Matos, João T.V.; Duarte, Regina M.B.O.; Lopes, Sónia P.; Silva, Artur M.S.; Duarte, Armando C.

    2017-01-01

    Organic Aerosols (OAs) are typically defined as highly complex matrices whose composition changes in time and space. Focusing on time vector, this work uses two-dimensional nuclear magnetic resonance (2D NMR) techniques to examine the structural features of water-soluble (WSOM) and alkaline-soluble organic matter (ASOM) sequentially extracted from fine atmospheric aerosols collected in an urban setting during cold and warm seasons. This study reveals molecular signatures not previously decoded in NMR-related studies of OAs as meaningful source markers. Although the ASOM is less hydrophilic and structurally diverse than its WSOM counterpart, both fractions feature a core with heteroatom-rich branched aliphatics from both primary (natural and anthropogenic) and secondary origin, aromatic secondary organics originated from anthropogenic aromatic precursors, as well as primary saccharides and amino sugar derivatives from biogenic emissions. These common structures represent those 2D NMR spectral signatures that are present in both seasons and can thus be seen as an “annual background” profile of the structural composition of OAs at the urban location. Lignin-derived structures, nitroaromatics, disaccharides, and anhydrosaccharides signatures were also identified in the WSOM samples only from periods identified as smoke impacted, which reflects the influence of biomass-burning sources. The NMR dataset on the H–C molecules backbone was also used to propose a semi-quantitative structural model of urban WSOM, which will aid efforts for more realistic studies relating the chemical properties of OAs with their atmospheric behavior. - Highlights: • 2D NMR spectroscopy was used to decode urban organic aerosols. • Water and alkaline soluble components of urban organic aerosols have been compared. • Persistence of urban organic aerosols composition across different seasons. • Annual background profile of the structural features of urban organic aerosols. • Semi

  9. Structure and organization of phospholipid/polysaccharide nanoparticles

    International Nuclear Information System (INIS)

    Gerelli, Y; Bari, M T Di; Deriu, A; Cantu, L; Colombo, P; Como, C; Motta, S; Sonvico, F; May, R

    2008-01-01

    In recent years nanoparticles and microparticles composed of polymeric or lipid material have been proposed as drug carriers for improving the efficacy of encapsulated drugs. For the production of these systems different materials have been proposed, among them phospholipids and polysaccharides due to their biocompatibility, biodegradability, low cost and safety. We report here a morphological and structural investigation, performed using cryo-TEM, static light scattering and small angle neutron and x-ray scattering, on phospholipid/saccharide nanoparticles loaded with a lipophilic positively charged drug (tamoxifen citrate) used in breast cancer therapy. The lipid component was soybean lecithin; the saccharide one was chitosan that usually acts as an outer coating increasing vesicle stability. The microscopy and scattering data indicate the presence of two distinct nanoparticle families: uni-lamellar vesicles with average radius 90 A and multi-lamellar vesicles with average radius 440 A. In both families the inner core is occupied by the solvent. The presence of tamoxifen gives rise to a multi-lamellar structure of the lipid outer shell. It also induces a positive surface charge into the vesicles, repelling the positively charged chitosan molecules which therefore do not take part in nanoparticle formation

  10. Structure and organization of phospholipid/polysaccharide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Gerelli, Y; Bari, M T Di; Deriu, A [Dipartimento di Fisica and CNISM, Universita degli Studi di Parma and CRS SOFT, INFM-CNR (Italy); Cantu, L [Dipartimento di Chimica, Biochimica e Biotecnologie per la Medicina-LITA, Universita di Milano (Italy); Colombo, P; Como, C; Motta, S; Sonvico, F [Dipartimento Farmaceutico, Universita degli Studi di Parma (Italy); May, R [Institut Laue-Langevin, Grenoble (France)], E-mail: Antonio.Deriu@fis.unipr.it

    2008-03-12

    In recent years nanoparticles and microparticles composed of polymeric or lipid material have been proposed as drug carriers for improving the efficacy of encapsulated drugs. For the production of these systems different materials have been proposed, among them phospholipids and polysaccharides due to their biocompatibility, biodegradability, low cost and safety. We report here a morphological and structural investigation, performed using cryo-TEM, static light scattering and small angle neutron and x-ray scattering, on phospholipid/saccharide nanoparticles loaded with a lipophilic positively charged drug (tamoxifen citrate) used in breast cancer therapy. The lipid component was soybean lecithin; the saccharide one was chitosan that usually acts as an outer coating increasing vesicle stability. The microscopy and scattering data indicate the presence of two distinct nanoparticle families: uni-lamellar vesicles with average radius 90 A and multi-lamellar vesicles with average radius 440 A. In both families the inner core is occupied by the solvent. The presence of tamoxifen gives rise to a multi-lamellar structure of the lipid outer shell. It also induces a positive surface charge into the vesicles, repelling the positively charged chitosan molecules which therefore do not take part in nanoparticle formation.

  11. Structure and organization of phospholipid/polysaccharide nanoparticles

    Science.gov (United States)

    Gerelli, Y.; Di Bari, M. T.; Deriu, A.; Cantù, L.; Colombo, P.; Como, C.; Motta, S.; Sonvico, F.; May, R.

    2008-03-01

    In recent years nanoparticles and microparticles composed of polymeric or lipid material have been proposed as drug carriers for improving the efficacy of encapsulated drugs. For the production of these systems different materials have been proposed, among them phospholipids and polysaccharides due to their biocompatibility, biodegradability, low cost and safety. We report here a morphological and structural investigation, performed using cryo-TEM, static light scattering and small angle neutron and x-ray scattering, on phospholipid/saccharide nanoparticles loaded with a lipophilic positively charged drug (tamoxifen citrate) used in breast cancer therapy. The lipid component was soybean lecithin; the saccharide one was chitosan that usually acts as an outer coating increasing vesicle stability. The microscopy and scattering data indicate the presence of two distinct nanoparticle families: uni-lamellar vesicles with average radius 90 Å and multi-lamellar vesicles with average radius 440 Å. In both families the inner core is occupied by the solvent. The presence of tamoxifen gives rise to a multi-lamellar structure of the lipid outer shell. It also induces a positive surface charge into the vesicles, repelling the positively charged chitosan molecules which therefore do not take part in nanoparticle formation.

  12. Hemispheric lateralization of topological organization in structural brain networks.

    Science.gov (United States)

    Caeyenberghs, Karen; Leemans, Alexander

    2014-09-01

    The study on structural brain asymmetries in healthy individuals plays an important role in our understanding of the factors that modulate cognitive specialization in the brain. Here, we used fiber tractography to reconstruct the left and right hemispheric networks of a large cohort of 346 healthy participants (20-86 years) and performed a graph theoretical analysis to investigate this brain laterality from a network perspective. Findings revealed that the left hemisphere is significantly more "efficient" than the right hemisphere, whereas the right hemisphere showed higher values of "betweenness centrality" and "small-worldness." In particular, left-hemispheric networks displayed increased nodal efficiency in brain regions related to language and motor actions, whereas the right hemisphere showed an increase in nodal efficiency in brain regions involved in memory and visuospatial attention. In addition, we found that hemispheric networks decrease in efficiency with age. Finally, we observed significant gender differences in measures of global connectivity. By analyzing the structural hemispheric brain networks, we have provided new insights into understanding the neuroanatomical basis of lateralized brain functions. Copyright © 2014 Wiley Periodicals, Inc.

  13. Structure of Csd3 from Helicobacter pylori, a cell shape-determining metallopeptidase

    International Nuclear Information System (INIS)

    An, Doo Ri; Kim, Hyoun Sook; Kim, Jieun; Im, Ha Na; Yoon, Hye Jin; Yoon, Ji Young; Jang, Jun Young; Hesek, Dusan; Lee, Mijoon; Mobashery, Shahriar; Kim, Soon-Jong; Lee, Byung Il; Suh, Se Won

    2015-01-01

    H. pylori Csd3 (HP0506), together with other peptidoglycan hydrolases, plays an important role in determining cell shape. Its crystal structure in the latent state is reported. Helicobacter pylori is associated with various gastrointestinal diseases such as gastritis, ulcers and gastric cancer. Its colonization of the human gastric mucosa requires high motility, which depends on its helical cell shape. Seven cell shape-determining genes (csd1, csd2, csd3/hdpA, ccmA, csd4, csd5 and csd6) have been identified in H. pylori. Their proteins play key roles in determining the cell shape through modifications of the cell-wall peptidoglycan by the alteration of cross-linking or by the trimming of peptidoglycan muropeptides. Among them, Csd3 (also known as HdpA) is a bifunctional enzyme. Its d, d-endopeptidase activity cleaves the d-Ala 4 -mDAP 3 peptide bond between cross-linked muramyl tetrapeptides and pentapeptides. It is also a d, d-carboxypeptidase that cleaves off the terminal d-Ala 5 from the muramyl pentapeptide. Here, the crystal structure of this protein has been determined, revealing the organization of its three domains in a latent and inactive state. The N-terminal domain 1 and the core of domain 2 share the same fold despite a very low level of sequence identity, and their surface-charge distributions are different. The C-terminal LytM domain contains the catalytic site with a Zn 2+ ion, like the similar domains of other M23 metallopeptidases. Domain 1 occludes the active site of the LytM domain. The core of domain 2 is held against the LytM domain by the C-terminal tail region that protrudes from the LytM domain

  14. Structure of Csd3 from Helicobacter pylori, a cell shape-determining metallopeptidase

    Energy Technology Data Exchange (ETDEWEB)

    An, Doo Ri [Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, Hyoun Sook [Seoul National University, Seoul 151-742 (Korea, Republic of); Seoul National University, Seoul 151 742 (Korea, Republic of); Kim, Jieun; Im, Ha Na; Yoon, Hye Jin; Yoon, Ji Young; Jang, Jun Young [Seoul National University, Seoul 151-742 (Korea, Republic of); Hesek, Dusan; Lee, Mijoon; Mobashery, Shahriar [University of Notre Dame, Notre Dame, IN 46556 (United States); Kim, Soon-Jong [Mokpo National University, Chonnam 534-729 (Korea, Republic of); Lee, Byung Il [National Cancer Center, Gyeonggi 410-769 (Korea, Republic of); Suh, Se Won, E-mail: sewonsuh@snu.ac.kr [Seoul National University, Seoul 151-742 (Korea, Republic of); Seoul National University, Seoul 151-742 (Korea, Republic of)

    2015-03-01

    H. pylori Csd3 (HP0506), together with other peptidoglycan hydrolases, plays an important role in determining cell shape. Its crystal structure in the latent state is reported. Helicobacter pylori is associated with various gastrointestinal diseases such as gastritis, ulcers and gastric cancer. Its colonization of the human gastric mucosa requires high motility, which depends on its helical cell shape. Seven cell shape-determining genes (csd1, csd2, csd3/hdpA, ccmA, csd4, csd5 and csd6) have been identified in H. pylori. Their proteins play key roles in determining the cell shape through modifications of the cell-wall peptidoglycan by the alteration of cross-linking or by the trimming of peptidoglycan muropeptides. Among them, Csd3 (also known as HdpA) is a bifunctional enzyme. Its d, d-endopeptidase activity cleaves the d-Ala{sup 4}-mDAP{sup 3} peptide bond between cross-linked muramyl tetrapeptides and pentapeptides. It is also a d, d-carboxypeptidase that cleaves off the terminal d-Ala{sup 5} from the muramyl pentapeptide. Here, the crystal structure of this protein has been determined, revealing the organization of its three domains in a latent and inactive state. The N-terminal domain 1 and the core of domain 2 share the same fold despite a very low level of sequence identity, and their surface-charge distributions are different. The C-terminal LytM domain contains the catalytic site with a Zn{sup 2+} ion, like the similar domains of other M23 metallopeptidases. Domain 1 occludes the active site of the LytM domain. The core of domain 2 is held against the LytM domain by the C-terminal tail region that protrudes from the LytM domain.

  15. Determinants and management outcomes of pelvic organ prolapse in a low resource setting.

    Science.gov (United States)

    Eleje, Gu; Udegbunam, Oi; Ofojebe, Cj; Adichie, Cv

    2014-09-01

    The last decade has seen significant progress in understanding of the pathophysiology, anatomy and management modalities of pelvic organ prolapse. A review of the way we manage this entity in a low resource setting has become necessary. The aim of the study is to determine the incidence, risk factors and management modalities of pelvic organ prolapse. A 5-year cross-sectional study with retrospective data collection of women who attended the gynecologic clinic in Nnamdi Azikiwe University Teaching Hospital, Nnewi, south-east Nigeria and were diagnosed of pelvic organ prolapse was made. Proforma was initially used for data collection before transfer to Epi-info 2008 (v 3.5.1; Epi Info, Centers for Disease Control and Prevention, Atlanta, GA) software. There were 199 cases of pelvic organ prolapse, out of a total gynecologic clinic attendance of 3082, thus giving an incidence of 6.5%. The mean age was 55.5 (15.9) years with a significant association between prolapse and advanced age (P < 0.001). The age range was 22-80 years. The leading determinants were menopause, advanced age, multiparity, chronic increase in intra-abdominal pressure (IAP) and prolonged labor. Out of the 147 patients with uterine prolapse, majority, 60.5% (89/147) had third degree prolapse. Vaginal hysterectomy with pelvic floor repair was the most common surgery performed. The average duration of hospital stay following surgery was 6.8 (2.9) days and the most common complication was urinary tract infection, 13.5% (27/199). The recurrence rate was 13.5% (27/199). Most of the patients who presented initially with pelvic organ prolapse were lost to follow-up. The incidence of pelvic organ prolapse in this study was 6.5% and the leading determinants of pelvic organ prolapse were - multiparity, menopause, chronic increase in IAP and advanced age. Most were lost to follow-up and a lesser proportion was offered conservative management. Early presentation of women is necessary so that conservative

  16. Relating microbial community structure to functioning in forest soil organic carbon transformation and turnover.

    Science.gov (United States)

    You, Yeming; Wang, Juan; Huang, Xueman; Tang, Zuoxin; Liu, Shirong; Sun, Osbert J

    2014-03-01

    Forest soils store vast amounts of terrestrial carbon, but we are still limited in mechanistic understanding on how soil organic carbon (SOC) stabilization or turnover is controlled by biotic and abiotic factors in forest ecosystems. We used phospholipid fatty acids (PLFAs) as biomarker to study soil microbial community structure and measured activities of five extracellular enzymes involved in the degradation of cellulose (i.e., β-1,4-glucosidase and cellobiohydrolase), chitin (i.e., β-1,4-N-acetylglucosaminidase), and lignin (i.e., phenol oxidase and peroxidase) as indicators of soil microbial functioning in carbon transformation or turnover across varying biotic and abiotic conditions in a typical temperate forest ecosystem in central China. Redundancy analysis (RDA) was performed to determine the interrelationship between individual PFLAs and biotic and abiotic site factors as well as the linkage between soil microbial structure and function. Path analysis was further conducted to examine the controls of site factors on soil microbial community structure and the regulatory pathway of changes in SOC relating to microbial community structure and function. We found that soil microbial community structure is strongly influenced by water, temperature, SOC, fine root mass, clay content, and C/N ratio in soils and that the relative abundance of Gram-negative bacteria, saprophytic fungi, and actinomycetes explained most of the variations in the specific activities of soil enzymes involved in SOC transformation or turnover. The abundance of soil bacterial communities is strongly linked with the extracellular enzymes involved in carbon transformation, whereas the abundance of saprophytic fungi is associated with activities of extracellular enzymes driving carbon oxidation. Findings in this study demonstrate the complex interactions and linkage among plant traits, microenvironment, and soil physiochemical properties in affecting SOC via microbial regulations.

  17. Potential and Actual Neonatal Organ and Tissue Donation After Circulatory Determination of Death.

    Science.gov (United States)

    Stiers, Justin; Aguayo, Cecile; Siatta, Angela; Presson, Angela P; Perez, Richard; DiGeronimo, Robert

    2015-07-01

    The need for transplants continues to exceed organ and tissue donor availability. Although recent surgical advances have resulted in successful transplants using very small pediatric donors, including neonates, the actual practice of neonatal organ donation after circulatory determination of death (DCDD) remains uncommon. To describe the percentage of neonates potentially eligible for DCDD, including those who underwent successful donation, and reasons for ineligibility in those who did not in a single neonatal intensive care unit (NICU). We obtained data from the Children's Hospital Neonatal Database and Intermountain Donor Services (IDS) organ procurement records. The 136 deaths that occurred in the NICU of the Primary Children's Hospital, Salt Lake City, Utah, from January 1, 2010, through May 7, 2013, were reviewed retrospectively from January 12 through July 1, 2014, to determine potential eligibility for DCDD as determined by IDS minimum eligibility criteria (requirement of life-sustaining interventions and weight >2 kg). For patients who did not undergo DCDD, we reviewed records to determine the reasons for ineligibility. Potential eligibility for DCDD among neonates who died in the study NICU. Of 136 deaths in the NICU, 60 (44.1%) met criteria for DCDD; however, fewer than 10% were referred appropriately to the regional organ procurement organization for evaluation. Forty-five neonates (33.1%) ultimately died within 90 minutes of withdrawal of life-sustaining interventions and thus would have been eligible for organ donation based on warm ischemic time. The most common causes of death among the 60 potentially eligible neonatal donors were neonatal encephalopathy (n = 17) and multiple congenital anomalies (n = 14). Nonreferral or late referral by the medical team was the most frequent reason for donor ineligibility, including 49 neonates (36.0%). Overall, only 4 neonates (2.9%) underwent successful DCDD. Although almost half of all neonatal deaths

  18. Structural organization of psychological defenses and coping strategies of preschool teachers with different levels of professional burnout

    Directory of Open Access Journals (Sweden)

    Тетяна Анатоліївна Колтунович

    2015-10-01

    Full Text Available The article deals with the actual problem of modern education system – preschool teachers’ professional burnout. Assumptions about the existence of the relationship between professional burnout, coping strategies and mechanisms of psychological defenses; about the determination of burnout at different stages of its formation according to the structural organization of coping and psychological defenses were empirically proven, and their leading and basic components were defined

  19. Economic Liberalization in Nepal: Determinants, Structure, and Trends of FDI

    Directory of Open Access Journals (Sweden)

    Raghu Bir Bista

    2017-03-01

    Full Text Available This research examined the relationship between FDI (Foreign Direct Investment and GDP (Gross Domestic Product along with the impact of FDI determinants on FDI inflow in Nepal. This research used literature review by doing multiple regression models. This research used an econometric model based on Cobb Douglas Production Model and a theoretical growth model based on Solow Growth. The result indicates the positive relationship between GDP and FDI. Furthermore, liberalization and privatization policies are positive, but insecurity is disturbing.

  20. Structural determination of some uranyl compounds by vibrational spectroscopy

    International Nuclear Information System (INIS)

    Rodriguez S, A.; Martinez Q, E.

    1990-07-01

    The vibrational spectra of different uranyl compounds has been studied and of it spectral information has been used the fundamental asymmetric vibrational frequency, to determine the length and constant bond force U=O by means of the combination of the concept of absorbed energy and the mathematical expression of Badger modified by Jones. It is intended a factor that simplifies the mathematical treatment and the results are compared with the values obtained for other methods. (Author)