Insights into the Halogen Oxidative Addition Reaction to Dinuclear Gold(I) Di(NHC) Complexes

KAUST Repository

Baron, Marco

2016-06-14

Gold(I) dicarbene complexes [Au2(MeIm-Y-ImMe)2](PF6)2(Y=CH2(1), (CH2)2(2), (CH2)4(4), MeIm=1-methylimidazol-2-ylidene) react with iodine to give the mixed-valence complex [Au(MeIm-CH2-ImMe)2AuI2](PF6)2(1 aI) and the gold(III) complexes [Au2I4(MeIm-Y-ImMe)2](PF6)2(2 cIand 4 cI). Reaction of complexes 1 and 2 with an excess of ICl allows the isolation of the tetrachloro gold(III) complexes [Au2Cl4(MeIm-CH2-ImMe)2](PF6)2(1 cCl) and [Au2Cl4(MeIm-(CH2)2-ImMe)2](Cl)2(2 cCl-Cl) (as main product); remarkably in the case of complex 2, the X-ray molecular structure of the crystals also shows the presence of I-Au-Cl mixed-sphere coordination. The same type of coordination has been observed in the main product of the reaction of complexes 3 or 4 with ICl. The study of the reactivity towards the oxidative addition of halogens to a large series of dinuclear bis(dicarbene) gold(I) complexes has been extended and reviewed. The complexes react with Cl2, Br2and I2to give the successive formation of the mixed-valence gold(I)/gold(III) n aXand gold(III) n cX(excluding compound 1 cI) complexes. However, complex 3 affords with Cl2and Br2the gold(II) complex 3 bX[Au2X2(MeIm-(CH2)3-ImMe)2](PF6)2(X=Cl, Br), which is the predominant species over compound 3 cXeven in the presence of free halogen. The observed different relative stabilities of the oxidised complexes of compounds 1 and 3 have also been confirmed by DFT calculations. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Insights into the Halogen Oxidative Addition Reaction to Dinuclear Gold(I) Di(NHC) Complexes

KAUST Repository

Baron, Marco; Tubaro, Cristina; Basato, Marino; Isse, Abdirisak Ahmed; Gennaro, Armando; Cavallo, Luigi; Graiff, Claudia; Dolmella, Alessandro; Falivene, Laura; Caporaso, Lucia

2016-01-01

Gold(I) dicarbene complexes [Au2(MeIm-Y-ImMe)2](PF6)2(Y=CH2(1), (CH2)2(2), (CH2)4(4), MeIm=1-methylimidazol-2-ylidene) react with iodine to give the mixed-valence complex [Au(MeIm-CH2-ImMe)2AuI2](PF6)2(1 aI) and the gold(III) complexes [Au2I4(Me

Theoretical investigation of inclusion complex formation of Gold (III – Dimethyldithiocarbamate anticancer agents with cucurbit[n = 5,6]urils

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Zabiollah Mahdavifar

2014-09-01

Full Text Available Gold (III-N,N-dimethyldithiocarbamate [DMDT(AuX2] complexes have recently gained increasing attention as potential anticancer agents because of their strong tumor cell growth–inhibitory effects, generally achieved by exploiting non-cisplatin-like mechanisms of action. The goal of our research work is to encapsulate the gold(III dimethyldithiocarbamate complexes as anticancer with cucurbit[n]urils (CB[n = 5, 6] by accurate calculations, to predict the inclusion complex formation of gold(III species with cucurbiturils (CB[n = 5, 6]. The calculations were carried out just for the 1:1 stoichiometric complexes. Upon encapsulation, binding energy, thermodynamic parameters, structural parameters and electronic structures of complexes are investigated. The results of the thermodynamic calculations and the binding energy show that the inclusion process is exothermic and the CB[6]/[DMDT(AuBr2] complex is more stable than other complexes. The final geometry of CB[n]/drugs indicates that the drugs were expelled from the cavity of CB[n]. NBO calculations reveal that the hydrogen bonding between CB[n] and drugs and electrostatic interactions are the major factors contributing to the overall stabilities of the complexes.

A general access to organogold(iii) complexes by oxidative addition of diazonium salts.

Science.gov (United States)

Huang, Long; Rominger, Frank; Rudolph, Matthias; Hashmi, A Stephen K

2016-05-11

At room temperature under mild photochemical conditions, namely irradiation with a simple blue light LED, gold(i) chloro complexes of both phosphane and carbene ligands in combination with aryldiazonium salts afford arylgold(iii) complexes. With chelating P,N-ligands cationic six- or five-membered chelate complexes were isolated in the form of salts with weakly coordinating counter anions that were brought in from the diazonium salt. With monodentate P ligands or N-heterocyclic carbene ligands and diazonium chlorides neutral arylgold(iii) dichloro complexes were obtained. The coordination geometry was determined by X-ray crystal structure analyses of representative compounds, a cis arrangement of the aryl and the phosphane ligand at the square planar gold(iii) center is observed.

Light-induced reduction of rhodium(III) and palladium(II) on titanium dioxide dispersions and the selective photochemical separation and recovery of gold(III), platinum(IV), and rhodium(III) in chloride media

Energy Technology Data Exchange (ETDEWEB)

Borgarello, E.; Serpone, N.; Emo, G.; Harris, R.; Pelizzetti, E.; Minero, C.

1986-12-03

Irradiation of aqueous TiO/sub 2/ dispersions containing palladium(II) or rhodium(III) chloride salts with AM1 simulated sunlight leads to the photoreduction of these metals, which are deposited on the semiconductor particle surface. Oxygen is detrimental to the photoreduction of rhodium(III) but not the photoreduction of palladium(II). However, in both cases the reduction process is most efficient if the solution contains CH/sub 3/OH, which acts to scavenge valence band holes of the illuminated TiO/sub 2/ semiconductor. The selective photoreduction and recovery of precious metals from a dilute solution (as might be found in industrial wastes) have been investigated for a mixture of gold(III), platinum(IV), and rhodium(III) chloride salts as a function of various parameters (pH, presence or absence of O/sub 2/, presence or absence of a hole scavenger, and the concentration of the semiconductor). At pH 0, gold is easily separated from platinum and rhodium. The rate of photoreduction of gold(III) on TiO/sub 2/ is nearly independent of the concentration of the semiconductor, under the experimental conditions employed; the limiting rate is 2.7 x 10/sup -7/ M s/sup -1/. The potential utility of this selective photochemical technique is discussed.

Gold(III) chloride catalyzed regioselective synthesis of pyrano[3,4-b]indol-1(9H)-ones and evaluation of anticancer potential towards human cervix adenocarcinoma.

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Praveen, Chandrasekaran; Ayyanar, Asairajan; Perumal, Paramasivan Thirumalai

2011-07-15

A highly regioselective synthesis of pyrano[3,4-b]indol-1(9H)-ones via gold(III) chloride catalyzed cycloisomerization of 3-ethynyl-indole-2-carboxylic acid was achieved in good to excellent yields. These compounds were screened for their in vitro cytotoxicity against human cervical (HeLa) cell lines. Out of ten compounds, three compounds (7d, 7e and 7j) showed comparable proliferation inhibitory activity against the standard drug cisplatin. Compound 7d was found to be the most efficacious with IC(50) value of 0.22μM. Copyright © 2011 Elsevier Ltd. All rights reserved.

Proof complexity of intuitionistic implicational formulas

Czech Academy of Sciences Publication Activity Database

Jeřábek, Emil

2017-01-01

Roč. 168, č. 1 (2017), s. 150-190 ISSN 0168-0072 EU Projects: European Commission(XE) 339691 - FEALORA Institutional support: RVO:67985840 Keywords : proof complexity * intuitionistic logic * implicational fragment Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.647, year: 2016 http://www.sciencedirect.com/science/article/pii/S0168007216301154

Structure and reactivity of a mononuclear gold(II) complex

Science.gov (United States)

Preiß, Sebastian; Förster, Christoph; Otto, Sven; Bauer, Matthias; Müller, Patrick; Hinderberger, Dariush; Hashemi Haeri, Haleh; Carella, Luca; Heinze, Katja

2017-12-01

Mononuclear gold(II) complexes are very rare labile species. Transient gold(II) species have been suggested in homogeneous catalysis and in medical applications, but their geometric and electronic structures have remained essentially unexplored: even fundamental data, such as the ionic radius of gold(II), are unknown. Now, an unprecedentedly stable neutral gold(II) complex of a porphyrin derivative has been isolated, and its structural and spectroscopic features determined. The gold atom adopts a 2+2 coordination mode in between those of gold(III) (four-coordinate square planar) and gold(I) (two-coordinate linear), owing to a second-order Jahn-Teller distortion enabled by the relativistically lowered 6s orbital of gold. The reactivity of this gold(II) complex towards dioxygen, nitrosobenzene and acids is discussed. This study provides insight on the ionic radius of gold(II), and allows it to be placed within the homologous series of nd9 Cu/Ag/Au divalent ions and the 5d8/9/10 Pt/Au/Hg 'relativistic' triad in the periodic table.

Neurosurgical implications of Carney complex.

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Watson, J C; Stratakis, C A; Bryant-Greenwood, P K; Koch, C A; Kirschner, L S; Nguyen, T; Carney, J A; Oldfield, E H

2000-03-01

The authors present their neurosurgical experience with Carney complex. Carney complex, characterized by spotty skin pigmentation, cardiac myxomas, primary pigmented nodular adrenocortical disease, pituitary tumors, and nerve sheath tumors (NSTs), is a recently described, rare, autosomal-dominant familial syndrome that is relatively unknown to neurosurgeons. Neurosurgery is required to treat pituitary adenomas and a rare NST, the psammomatous melanotic schwannoma (PMS), in patients with Carney complex. Cushing's syndrome, a common component of the complex, is caused by primary pigmented nodular adrenocortical disease and is not secondary to an adrenocorticotropic hormone-secreting pituitary adenoma. The authors reviewed 14 cases of Carney complex, five from the literature and nine from their own experience. Of the 14 pituitary adenomas recognized in association with Carney complex, 12 developed growth hormone (GH) hypersecretion (producing gigantism in two patients and acromegaly in 10), and results of immunohistochemical studies in one of the other two were positive for GH. The association of PMSs with Carney complex was established in 1990. Of the reported tumors, 28% were associated with spinal nerve sheaths. The spinal tumors occurred in adults (mean age 32 years, range 18-49 years) who presented with pain and radiculopathy. These NSTs may be malignant (10%) and, as with the cardiac myxomas, are associated with significant rates of morbidity and mortality. Because of the surgical comorbidity associated with cardiac myxoma and/or Cushing's syndrome, recognition of Carney complex has important implications for perisurgical patient management and family screening. Study of the genetics of Carney complex and of the biological abnormalities associated with the tumors may provide insight into the general pathobiological abnormalities associated with the tumors may provide insight into the general pathobiological features of pituitary adenomas and NSTs.

Cisplatin carbonato complexes. Implications for uptake, antitumor properties, and toxicity.

Science.gov (United States)

Centerwall, Corey R; Goodisman, Jerry; Kerwood, Deborah J; Dabrowiak, James C

2005-09-21

The reaction of aquated cisplatin with carbonate which is present in culture media and blood is described. The first formed complex is a monochloro monocarbonato species, which upon continued exposure to carbonate slowly forms a biscarbonato complex. The formation of carbonato species under conditions that simulate therapy may have important implications for uptake, antitumor properties, and toxicity of cisplatin.

Individual differences in emotional complexity: their psychological implications.

Science.gov (United States)

Kang, Sun-Mee; Shaver, Phillip R

2004-08-01

Two studies explored the nature and psychological implications of individual differences in emotional complexity, defined as having emotional experiences that are broad in range and well differentiated. Emotional complexity was predicted to be associated with private self-consciousness, openness to experience, empathic tendencies, cognitive complexity, ability to differentiate among named emotions, range of emotions experienced daily, and interpersonal adaptability. The Range and Differentiation of Emotional Experience Scale (RDEES) was developed to test these hypotheses. In Study 1 (N=1,129) students completed questionnaire packets containing the RDEES and various outcome measures. Study 2 (N=95) included the RDEES and non-self-report measures such as peer reports, complexity of representations of the emotion domain, and level of ego development measured by a sentence completion test. Results supported all of the hypotheses, providing extensive evidence for the RDEES's construct validity. Findings were discussed in terms of the role of emotional complexity in ego maturity and interpersonal adaptability.

Analysis of gold(I/III)-complexes by HPLC-ICP-MS demonstrates gold(III) stability in surface waters.

Science.gov (United States)

Ta, Christine; Reith, Frank; Brugger, Joël; Pring, Allan; Lenehan, Claire E

2014-05-20

Understanding the form in which gold is transported in surface- and groundwaters underpins our understanding of gold dispersion and (bio)geochemical cycling. Yet, to date, there are no direct techniques capable of identifying the oxidation state and complexation of gold in natural waters. We present a reversed phase ion-pairing HPLC-ICP-MS method for the separation and determination of aqueous gold(III)-chloro-hydroxyl, gold(III)-bromo-hydroxyl, gold(I)-thiosulfate, and gold(I)-cyanide complexes. Detection limits for the gold species range from 0.05 to 0.30 μg L(-1). The [Au(CN)2](-) gold cyanide complex was detected in five of six waters from tailings and adjacent monitoring bores of working gold mines. Contrary to thermodynamic predictions, evidence was obtained for the existence of Au(III)-complexes in circumneutral, hypersaline waters of a natural lake overlying a gold deposit in Western Australia. This first direct evidence for the existence and stability of Au(III)-complexes in natural surface waters suggests that Au(III)-complexes may be important for the transport and biogeochemical cycling of gold in surface environments. Overall, these results show that near-μg L(-1) enrichments of Au in environmental waters result from metastable ligands (e.g., CN(-)) as well as kinetically controlled redox processes leading to the stability of highly soluble Au(III)-complexes.

Causal-implicative relationships in the Serbian hypotaxis (Complex of generative complex sentences

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Vojvodić Dojčil P.

2015-01-01

Full Text Available The paper analyzes the causal-implicative relationships in the segmented complex sentences with a “closed” (asymmetric, mandatory bi-situational generative (conditional semantic structure on the corpus of the Serbian language. The generative (conditional semantic structure consists of meaningfully interconnected antecedents and consequents that are based on the principle of subordination. These sentences are characterized with a general causal link due to the specific implicative relationship between the segments that can be realized within dependent clauses with diverse categorically-differential semantics (i.e. causal, consecutive, final, conditional and concessive. The author reaches a conclusion that the given implicative relationships (P ⇒ Q, P ⇐ Q/Q ⇒ P, P ⇔Q, P ⇒ Q´ Δ P´ ⇒ Q represent, in fact, semantic invariants of generative complex sentences. It is pointed out that the structure, formation and functioning of these relationships (sentences are always determined by the interconnectedness of syntax and lexicon. They are based on a general causal adverbial meaning of the conjunctions in a subordinate clause, which are also used to determine the adverbial semantics of a sentence as a whole. The article discusses in particular the aspectual-temporal correlations that are realized in complex sentences with a generative structure. It has been noted very often in the literature that there is no differentiation made among all of the types of the hypothetical conditionality - real, eventual, potential and unreal. The paper analyzes taxis of simultaneity and succession (anteriority/posteriority of the main and subordinate clause predicates in conditional sentences as a special type of the relative-temporal relationships within the same temporal plan. In order to interpret these correlations, the Serbian data was compared to the data in Russian and Polish. It is noted that the Northern Slavic languages (in this case Russian and

Implications of complex adaptive systems theory for interpreting research about health care organizations.

Science.gov (United States)

Jordon, Michelle; Lanham, Holly Jordan; Anderson, Ruth A; McDaniel, Reuben R

2010-02-01

Data about health care organizations (HCOs) are not useful until they are interpreted. Such interpretations are influenced by the theoretical lenses used by the researcher. Our purpose was to suggest the usefulness of theories of complex adaptive systems (CASs) in guiding research interpretation. Specifically, we addressed two questions: (1) What are the implications for interpreting research observations in HCOs of the fact that we are observing relationships among diverse agents? (2) What are the implications for interpreting research observations in HCOs of the fact that we are observing relationships among agents that learn? We defined diversity and learning and the implications of the non-linear relationships among agents from a CAS perspective. We then identified some common analytical practices that were problematic and may lead to conceptual and methodological errors. Then we described strategies for interpreting the results of research observations. We suggest that the task of interpreting research observations of HCOs could be improved if researchers take into account that the systems they study are CASs with non-linear relationships among diverse, learning agents. Our analysis points out how interpretation of research results might be shaped by the fact that HCOs are CASs. We described how learning is, in fact, the result of interactions among diverse agents and that learning can, by itself, reduce or increase agent diversity. We encouraged researchers to be persistent in their attempts to reason about complex systems and learn to attend not only to structures, but also to processes and functions of complex systems.

Ensemble Sensitivity Analysis of a Severe Downslope Windstorm in Complex Terrain: Implications for Forecast Predictability Scales and Targeted Observing Networks

Science.gov (United States)

2013-09-01

observations, linear regression finds the straight line that explains the linear relationship of the sample. This line is given by the equation y = mx + b...SENSITIVITY ANALYSIS OF A SEVERE DOWNSLOPE WINDSTORM IN COMPLEX TERRAIN: IMPLICATIONS FOR FORECAST PREDICTABILITY SCALES AND TARGETED OBSERVING...SENSITIVITY ANALYSIS OF A SEVERE DOWNSLOPE WINDSTORM IN COMPLEX TERRAIN: IMPLICATIONS FOR FORECAST PREDICTABILITY SCALES AND TARGETED OBSERVING NETWORKS

Luminescent cyclometalated alkynylgold(III) complexes with 6-phenyl-2,2'-bipyridine derivatives: synthesis, characterization, electrochemistry, photophysics, and computational studies.

Science.gov (United States)

Au, Vonika Ka-Man; Lam, Wai Han; Wong, Wing-Tak; Yam, Vivian Wing-Wah

2012-07-16

A novel class of luminescent gold(III) complexes containing various tridentate cyclometalating ligands derived from 6-phenyl-2,2'-bipyridine and alkynyl ligands, [Au(RC^N^N)(C≡C-R')]PF(6), has been successfully synthesized and characterized. One of the complexes has also been determined by X-ray crystallography. Electrochemical studies show a ligand-centered reduction originated from the cyclometalating RC^N^N ligands as well as an alkynyl-centered oxidation. The electronic absorption and photoluminescence properties of the complexes have also been investigated. In acetonitrile at room temperature, the complexes show intense absorption at higher energy region with wavelength shorter than 320 nm, and a moderately intense broad absorption band at 374-406 nm, assigned as the metal-perturbed intraligand π-π* transition of the cyclometalating RC(∧)N(∧)N ligand, with some charge transfer character from the aryl ring to the bipyridine moiety. Most of the complexes have been observed to show vibronic-structured emission bands at 469-550 nm in butyronitile glass at 77 K, assigned to an intraligand excited state of the RC^N^N ligand, with some charge transfer character from the aryl to the bipyridyine moiety. Insights into the origin of the absorption and emission have also been provided by density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations.

Toxicological evaluation of complex industrial wastes: Implications for exposure assessment

Energy Technology Data Exchange (ETDEWEB)

DeMarini, D.M.; Gallagher, J.E.; Houk, V.S.; Simmons, J.E.

1990-07-01

We evaluated a variety of short-term bioassays to construct a battery of tests that could be used for assessing the biological effects of potentially hazardous complex industrial wastes. Ten samples were studied for hepatotoxicity; these samples and an additional five were studied for mutagenicity. Although the data are limited to these samples, the results suggest that the Salmonella assay (strain TA98) or a prophage-induction assay (both in the presence of S9) in combination with determination of relative liver weight and levels of a set of serum enzymes in rats may provide a battery of tests suitable to characterize complex industrial wastes for mutagenic and hepatotoxic potential. The biological activities exhibited by the wastes were not readily predicted by the chemical profiles of the wastes, emphasizing the importance of characterizing potentially hazardous complex industrial wastes by both chemical and biological means. DNA from liver, lung, and bladder of rats exposed to some of the wastes was analyzed by the 32P-postlabeling technique for the presence of DNA adducts. A waste that produced mutagenic urine produced a DNA adduct in bladder DNA. The implications of this approach for assessment of exposure to complex hazardous waste mixtures are discussed.

A retrospective study of phonetic inventory complexity in acquisition of Spanish: Implications for phonological universals

OpenAIRE

Cataño, Lorena; Barlow, Jessica A.; Moyna, María Irene

2009-01-01

This study evaluates 39 different phonetic inventories of 16 Spanish-speaking children (ages 0;11 to 5;1) in terms of hierarchical complexity. Phonetic featural differences are considered in order to evaluate the proposed implicational hierarchy of Dinnsen et al.’s phonetic inventory typology for English. The children’s phonetic inventories are examined independently and in relation to one another. Five hierarchical complexity levels are proposed, similar to those of English and other languag...

Precipitation of gold by the reaction of aqueous gold(III)-chloride with cyanobacteria at 25-80 C -- Studied by x-ray absorption spectroscopy

International Nuclear Information System (INIS)

Lengke, M. F.; Ravel, B.; Fleet, M. E.; Wanger, G.; Gordon, R. A.; Southam, G.

2007-01-01

The mechanisms of gold precipitation by the interaction of cyanobacteria (Plectonema boryanum UTEX 485) and gold(III) chloride aqueous solutions (7.6 mmol/L final gold) have been studied at 25, 60, and 80 C, using both laboratory and real-time synchrotron radiation absorption spectroscopy experiments. Addition of aqueous gold(III) chloride to the cyanobacterial culture initially promoted the precipitation of amorphous gold(I) sulfide at the cell walls and finally caused the formation of octahedral (111) platelets (<1 to 6 (micro)m) of gold metal near cell surfaces and in solutions. X-ray absorption spectroscopy results confirmed that the reduction mechanism of gold(III) chloride to elemental gold by cyanobacteria involves the formation of an intermediate Au(I) species, gold(I) sulfide, with sulfur originating from cyanobacterial proteins, presumably cysteine or methionine. Although the bioreduction of gold(III) chloride to gold(I) sulfide was relatively rapid at all temperatures, the reaction rate increased with the increase in temperature. At the completion of the experiments, elemental gold was the major species present at all temperatures

Synthesis, crystal structures, and characterization of double complex salts [Au(en)2][Rh(NO2)6]·2H2O and [Au(en)2][Rh(NO2)6

Science.gov (United States)

Plyusnin, Pavel E.; Makotchenko, Evgenia V.; Shubin, Yury V.; Baidina, Iraida A.; Korolkov, Ilya V.; Sheludyakova, Liliya A.; Korenev, Sergey V.

2015-11-01

Double complex salts of rhodium(III) and gold(III) of the composition [Au(en)2][Rh(NO2)6]·2H2O (1) and [Au(en)2][Rh(NO2)6] (2) have been prepared. Crystal structures of the compounds have been determined by single crystal X-ray diffraction. The compounds have been characterized by PXRD, IR, far-IR, CHN and DTA. The complexes have a layered structures. The presence of water in 1 makes the structure of the hydrated DCS less dense as compared to the anhydrous one. The environment of the cation and the anion in the two structures is the same, oxygen atoms of the nitro groups are involved in hydrogen bonds N-H⋯O, N⋯O distances being approximately the same. The structures of 1 and 2 are notable in having shortened contacts between the gold atoms and the oxygen atoms of the nitro groups of the neighboring complex anions. The thermal behavior of the complexes in a hydrogen atmosphere was investigated. The final product of thermolysis prepared at the temperature 600°C is a two-phase mixture of pure metallic gold and the solid solution Rh0.93Au0.07.

A Simple and Selective Spectrophotometric Method for the Determination of Trace Gold in Real, Environmental, Biological, Geological and Soil Samples Using Bis (Salicylaldehyde Orthophenylenediamine

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Rubina Soomro

2008-01-01

Full Text Available A simple high sensitive, selective, and rapid spectrophotometric method for the determination of trace gold based on the rapid reaction of gold(III with bis(salicylaldehydeorthophenylenediamine (BSOPD in aqueous and micellar media has been developed. BSOPD reacts with gold(III in slightly acidic solution to form a 1:1 brownish-yellow complex, which has an maximum absorption peak at 490 nm in both aqueous and micellar media. The most remarkable point of this method is that the molar absorptivities of the gold-BSOPD complex form in the presence of the nonionic TritonX-100 surfactant are almost a 10 times higher than the value observed in the aqueous solution, resulting in an increase in the sensitivity and selectivity of the method. The apparent molar absorptivities were found to be 2.3 × 104 L mol−1 cm−1 and 2.5 × 105 L mol−1 cm−1 in aqueous and micellar media, respectively. The reaction is instantaneous and the maximum absorbance was obtained after 10 min at 490 nm and remains constant for over 24 h at room temperature. The linear calibration graphs were obtained for 0.1 –30 mg L−1 and 0.01 –30 mg L−1 of gold(III in aqueous and surfactant media, respectively. The interference from over 50 cations, anions and complexing agents has been studied at 1 mg L−1 of Au(III; most metal ions can be tolerated in considerable amounts in aqueous micellar solutions. The Sandell’s sensitivity, the limit of detection and relative standard deviation (n = 9 were found to be 5 ng cm−2, 1 ng mL−1 and 2%, respectively in aqueous micellar solutions. Its sensitivity and selectivity are remarkably higher than that of other reagents in the literature. The proposed method was successfully used in the determination of gold in several standard reference materials (alloys and steels, environmental water samples (potable and polluted, and biological samples (blood and urine, geological, soil and complex synthetic mixtures. The results obtained agree

Recovery of carrier-free gold-195

International Nuclear Information System (INIS)

Iofa, B.Z.; Ivanova, N.A.

1995-01-01

It is known that gold(III) is readily extracted from nitric acid solutions with ethers. The authors have studied extraction of trace amounts of gold(III) from nitric acid solutions with diethyl and diisopropyl ethers in the presence of significant excess of Pt(IV). Distribution coefficients of gold(III) were measured radiometrically using carrier-free gold-195 or spectrophotometrically in the presence of platinum(IV). Very high coefficients of gold separation from platinum may be achieved. Preliminary experiments have shown that zinc-65 was not extracted with ethers from nitric acid solutions. As an extraction system, the authors have chosen the system 10 M HNO 3 -diisopropyl ether. After model experiments, the authors have performed recovery of carrier-free gold-195 from a real platinum target irradiated with protons in a cyclotron

Charge-Transfer Dynamics in the Lowest Excited State of a Pentacene–Fullerene Complex: Implications for Organic Solar Cells

KAUST Repository

Joseph, Saju

2017-10-02

We characterize the dynamic nature of the lowest excited state in a pentacene/C60 complex on the femtosecond time scale, via a combination of ab initio molecular dynamics and time-dependent density functional theory. We analyze the correlations between the molecular vibrations of the complex and the oscillations in the electron-transfer character of its lowest excited state, which point to vibration-induced coherences between the (pentacene-based) local-excitation (LE) state and the complex charge-transfer (CT) state. We discuss the implications of our results on this model system for the exciton-dissociation process in organic solar cells.

The Complexity of the Implications of Globalization in the Context of the Current Global Economy

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Raluca Ionela CREŢOIU

2014-03-01

Full Text Available Globalization represents a controversial phenomenon both because of its complexity and because of the various implications it has on the global economy. Globalization will act simultaneously on many levels, its effects being correlated with the diversity of the angles from which this phenomenon can be approached from – economic, social, politic, cultural, philosophic etc. The article represents an incursion into the issue regarding the implications and effects of globalization grouped in several areas of analysis such as the disappearance of borders, the effects on culture, the effects on the education, the impact on labour market impact and the phenomenon of immigration, the effects of globalization in the context of the food crisis underdevelopment and poverty. To complete the analysis that points out enough elements considered to be negative, at the end of the article, there are also approached the development opportunities that globalization can offer in terms of boosting the economic exchanges, the exchange of genuine cultural values and ensuring a transfer of information at a global scale, so necessary for the scientific and technological progress.  The conclusions of the article weighs the many aspects highlighted, both negative and positive, and suggests a series of useful research directions in order to fathom the complex features of this concept so controversial – globalization.

General and Robust Strategies for Multifunctional Organic-Inorganic Nanocompositesvia Direct Growth of Monodisperse Nanocrystals Intimately and Permanently Connected with Polymers

Science.gov (United States)

2016-04-21

cells: from complex nanostructure to planar heterojunction ”, Journal of Materials Chemistry A, 2, 5994 (2014). (featured on Cover of Journal of...naphthalenide solution. Trifluoroacetic acid (TFA, 99%), Yttrium(III) oxide (Y2O3, 99.99%), Ytterbium(III) oxide (Yb2O3, 99.9%), Erbium(III) oxide ...Er2O3, ≥99.99%) and Thulium(III) oxide (Tm2O3, 99.9%) were purchased from Sigma-Aldrich and used as received. Gold(III) chloride trihydrate (HAuCl4·3H2O

Interpersonal Perception: Cognitive Complexity and Trait Implication

Science.gov (United States)

Halverson, Charles F., Jr.

1970-01-01

Demonstrates that evaluative connotations of personality characteristics have more persuasive effect on interpersonal judgment for persons low in cognitive complexity than for cognitively complex persons. Stresses need for conceptualizing interpersonal judgment as function of interaction between cognitive complexity and evaluative requirements of…

Alkyne hydroarylation with Au N-heterocyclic carbene catalysts

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Cristina Tubaro

2013-02-01

Full Text Available Mono- and dinuclear gold complexes with N-heterocyclic carbene (NHC ligands have been employed as catalysts in the intermolecular hydroarylation of alkynes with simple unfunctionalised arenes. Both mono- and dinuclear gold(III complexes were able to catalyze the reaction; however, the best results were obtained with the mononuclear gold(I complex IPrAuCl. This complex, activated with one equivalent of silver tetrafluoroborate, exhibited under acidic conditions at room temperature much higher catalytic activity and selectivity compared to more commonly employed palladium(II catalysts. Moreover, the complex was active, albeit to a minor extent, even under neutral conditions, and exhibited lower activity but higher selectivity compared to the previously published complex AuCl(PPh3. Preliminary results on intramolecular hydroarylations using this catalytic system indicate, however, that alkyne hydration by traces of water may become a serious competing reaction.

Frustration and disorder in granular media and tectonic blocks: implications for earthquake complexity

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A. Sornette

1994-01-01

Full Text Available We present exploratory analogies and speculations on the mechanisms underlying the organization of faulting and earthquake in the earth crust. The mechanical properties of the brittle lithosphere at scales of the order or larger than a few kilometers are proposed to be analogous to those of non-cohesive granular media, since both systems present stress amplitudes controlled by gravity, and shear band (faulting localization is determined by a type of friction Mohr-Coulomb rupture criterion. here, we explore the implications of this correspondence with respect to the origin of tectonic and earthquake complexity, on the basis of the existing experimental data on granular media available in the mechanical literature. An important observation is that motions and deformations of non-cohesive granular media are characterized by important fluctuations both in time (sudden breaks, avalanches, which are analogous to earthquakes and space (strain localizations, yield surfaces forming sometimes complex patterns. This is in apparent contradiction with the conventional wisdom in mechanics, based on the standard tendency to homogenize, which has led to dismiss fluctuations as experimental noise. On the basis of a second analogy with spinglasses and neural networks, based on the existence of block and grain packing disorder and block rotation "frustration", we suggest that these fluctuations observed both at large scales and at the block scale constitute an intrinsic signature of the mechanics of granular media. The space-time complexity observed in faulting and earthquake phenomenology is thus proposed to result form the special properties of the mechanics of granular media, dominated by the "frustration" of the kinematic deformations of its constitutive blocks.

Renal Tumor Anatomic Complexity: Clinical Implications for Urologists.

Science.gov (United States)

Joshi, Shreyas S; Uzzo, Robert G

2017-05-01

Anatomic tumor complexity can be objectively measured and reported using nephrometry. Various scoring systems have been developed in an attempt to correlate tumor complexity with intraoperative and postoperative outcomes. Nephrometry may also predict tumor biology in a noninvasive, reproducible manner. Other scoring systems can help predict surgical complexity and the likelihood of complications, independent of tumor characteristics. The accumulated data in this new field provide provocative evidence that objectifying anatomic complexity can consolidate reporting mechanisms and improve metrics of comparisons. Further prospective validation is needed to understand the full descriptive and predictive ability of the various nephrometry scores. Copyright © 2017 Elsevier Inc. All rights reserved.

Coprecipitation of gold(III) complex ions with manganese(II) hydroxide and their stoichiometric reduction to atomic gold (Au(0)): analysis by Mössbauer spectroscopy and XPS.

Science.gov (United States)

Yamashita, Mamiko; Ohashi, Hironori; Kobayashi, Yasuhiro; Okaue, Yoshihiro; Kurisaki, Tsutomu; Wakita, Hisanobu; Yokoyama, Takushi

2008-03-01

To elucidate the formation process of precursor of gold-supported manganese dioxide (MnO2), the coprecipitation behavior of [AuCl4-n(OH)n](-) (n=0-4) (Au(III)) complex ions with manganese(II) hydroxide (Mn(OH)2 and the change in their chemical state were examined. The Au(III) complex ions were rapidly and effectively coprecipitated with Mn(OH)(2) at pH 9. According to the Mössbauer spectra for gold (Au) coprecipitated with Mn(OH)2, below an Au content of 60 wt% in the coprecipitates, all of the coprecipitated Au existed in the atomic state (Au(0)), while, above an Au content of 65 wt%, part of the gold existed in the Au(III) state, and the proportion increased with increasing coprecipitated Au content. Based on the results of X-ray photoelectron spectroscopy, Mn(II) in Mn(OH)2 converted to Mn(IV) in conjunction with coprecipitation of Au(III) complex ions. These results indicate that the rapid stoichiometric reduction of Au(III) to Au(0) is caused by electron transfer from Mn(II) in Mn(OH)2 to the Au(III) complex ion through an Mn-O-Au bond.

Targeting aquaporin function: potent inhibition of aquaglyceroporin-3 by a gold-based compound.

Directory of Open Access Journals (Sweden)

Ana Paula Martins

Full Text Available Aquaporins (AQPs are membrane channels that conduct water and small solutes such as glycerol and are involved in many physiological functions. Aquaporin-based modulator drugs are predicted to be of broad potential utility in the treatment of several diseases. Until today few AQP inhibitors have been described as suitable candidates for clinical development. Here we report on the potent inhibition of AQP3 channels by gold(III complexes screened on human red blood cells (hRBC and AQP3-transfected PC12 cells by a stopped-flow method. Among the various metal compounds tested, Auphen is the most active on AQP3 (IC(50 = 0.8±0.08 µM in hRBC. Interestingly, the compound poorly affects the water permeability of AQP1. The mechanism of gold inhibition is related to the ability of Au(III to interact with sulphydryls groups of proteins such as the thiolates of cysteine residues. Additional DFT and modeling studies on possible gold compound/AQP adducts provide a tentative description of the system at a molecular level. The mapping of the periplasmic surface of an homology model of human AQP3 evidenced the thiol group of Cys40 as a likely candidate for binding to gold(III complexes. Moreover, the investigation of non-covalent binding of Au complexes by docking approaches revealed their preferential binding to AQP3 with respect to AQP1. The high selectivity and low concentration dependent inhibitory effect of Auphen (in the nanomolar range together with its high water solubility makes the compound a suitable drug lead for future in vivo studies. These results may present novel metal-based scaffolds for AQP drug development.

Discovery of rare variants via sequencing: implications for the design of complex trait association studies.

Directory of Open Access Journals (Sweden)

Bingshan Li

2009-05-01

Full Text Available There is strong evidence that rare variants are involved in complex disease etiology. The first step in implicating rare variants in disease etiology is their identification through sequencing in both randomly ascertained samples (e.g., the 1,000 Genomes Project and samples ascertained according to disease status. We investigated to what extent rare variants will be observed across the genome and in candidate genes in randomly ascertained samples, the magnitude of variant enrichment in diseased individuals, and biases that can occur due to how variants are discovered. Although sequencing cases can enrich for casual variants, when a gene or genes are not involved in disease etiology, limiting variant discovery to cases can lead to association studies with dramatically inflated false positive rates.

Analyzing complex wake-terrain interactions and its implications on wind-farm performance.

Science.gov (United States)

Tabib, Mandar; Rasheed, Adil; Fuchs, Franz

2016-09-01

Rotating wind turbine blades generate complex wakes involving vortices (helical tip-vortex, root-vortex etc.).These wakes are regions of high velocity deficits and high turbulence intensities and they tend to degrade the performance of down-stream turbines. Hence, a conservative inter-turbine distance of up-to 10 times turbine diameter (10D) is sometimes used in wind-farm layout (particularly in cases of flat terrain). This ensures that wake-effects will not reduce the overall wind-farm performance, but this leads to larger land footprint for establishing a wind-farm. In-case of complex-terrain, within a short distance (say 10D) itself, the nearby terrain can rise in altitude and be high enough to influence the wake dynamics. This wake-terrain interaction can happen either (a) indirectly, through an interaction of wake (both near tip vortex and far wake large-scale vortex) with terrain induced turbulence (especially, smaller eddies generated by small ridges within the terrain) or (b) directly, by obstructing the wake-region partially or fully in its flow-path. Hence, enhanced understanding of wake- development due to wake-terrain interaction will help in wind farm design. To this end the current study involves: (1) understanding the numerics for successful simulation of vortices, (2) understanding fundamental vortex-terrain interaction mechanism through studies devoted to interaction of a single vortex with different terrains, (3) relating influence of vortex-terrain interactions to performance of a wind-farm by studying a multi-turbine wind-farm layout under different terrains. The results on interaction of terrain and vortex has shown a much faster decay of vortex for complex terrain compared to a flatter-terrain. The potential reasons identified explaining the observation are (a) formation of secondary vortices in flow and its interaction with the primary vortex and (b) enhanced vorticity diffusion due to increased terrain-induced turbulence. The implications of

Hydration of the sulfuric acid-methylamine complex and implications for aerosol formation.

Science.gov (United States)

Bustos, Danielle J; Temelso, Berhane; Shields, George C

2014-09-04

The binary H2SO4-H2O nucleation is one of the most important pathways by which aerosols form in the atmosphere, and the presence of ternary species like amines increases aerosol formation rates. In this study, we focus on the hydration of a ternary system of sulfuric acid (H2SO4), methylamine (NH2CH3), and up to six waters to evaluate its implications for aerosol formation. By combining molecular dynamics (MD) sampling with high-level ab initio calculations, we determine the thermodynamics of forming H2SO4(NH2CH3)(H2O)n, where n = 0-6. Because it is a strong acid-base system, H2SO4-NH2CH3 quickly forms a tightly bound HSO4(-)-NH3CH3(+) complex that condenses water more readily than H2SO4 alone. The electronic binding energy of H2SO4-NH2CH3 is -21.8 kcal mol(-1) compared with -16.8 kcal mol(-1) for H2SO4-NH3 and -12.8 kcal mol(-1) for H2SO4-H2O. Adding one to two water molecules to the H2SO4-NH2CH3 complex is more favorable than adding to H2SO4 alone, yet there is no systematic difference for n ≥ 3. However, the average number of water molecules around H2SO4-NH2CH3 is consistently higher than that of H2SO4, and it is fairly independent of temperature and relative humidity.

Visual Complexity: A Review

Science.gov (United States)

Donderi, Don C.

2006-01-01

The idea of visual complexity, the history of its measurement, and its implications for behavior are reviewed, starting with structuralism and Gestalt psychology at the beginning of the 20th century and ending with visual complexity theory, perceptual learning theory, and neural circuit theory at the beginning of the 21st. Evidence is drawn from…

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Pyranoindolones; positional isomers; gold catalysis; chemical synthesis; ... for the synthesis of isomeric pyranoindolones was achievedby employing gold(III) ... that three compounds exhibited activitycomparable with the standard cis-platin ( I ...

Linking Complexity and Sustainability Theories: Implications for Modeling Sustainability Transitions

Directory of Open Access Journals (Sweden)

Camaren Peter

2014-03-01

Full Text Available In this paper, we deploy a complexity theory as the foundation for integration of different theoretical approaches to sustainability and develop a rationale for a complexity-based framework for modeling transitions to sustainability. We propose a framework based on a comparison of complex systems’ properties that characterize the different theories that deal with transitions to sustainability. We argue that adopting a complexity theory based approach for modeling transitions requires going beyond deterministic frameworks; by adopting a probabilistic, integrative, inclusive and adaptive approach that can support transitions. We also illustrate how this complexity-based modeling framework can be implemented; i.e., how it can be used to select modeling techniques that address particular properties of complex systems that we need to understand in order to model transitions to sustainability. In doing so, we establish a complexity-based approach towards modeling sustainability transitions that caters for the broad range of complex systems’ properties that are required to model transitions to sustainability.

Further assessment of seismic hazard/risk in the Bushveld Complex platinum mines and the implication for regional and local support design.

CSIR Research Space (South Africa)

Brink, AVZ

2002-03-01

Full Text Available Final Project Report Further assessment of seismic hazard/risk in the Bushveld Complex platinum mines and the implication for regional and local support design. A.v.Z Brink, M.K.C. Roberts, S.M Spottiswoode Research Agency: CSIR: Division of Mining... on the VCR. An industry workshop on local support requirements in areas of higher seismic risk resulted in the specification of support requirements. A maximum design parameter for yielding support in terms of the ground motion velocity is 1 m...

The complexity and implications of yeast prion domains

Science.gov (United States)

2011-01-01

Prions are infectious proteins with altered conformations converted from otherwise normal host proteins. While there is only one known mammalian prion protein, PrP, a handful of prion proteins have been identified in the yeast Saccharomyces cerevisiae. Yeast prion proteins usually have a defined region called prion domain (PrD) essential for prion properties, which are typically rich in glutamine (Q) and asparagine (N). Despite sharing several common features, individual yeast PrDs are generally intricate and divergent in their compositional characteristics, which potentially implicates their prion phenotypes, such as prion-mediated transcriptional regulations. PMID:22156731

An assessment of hydrothermal alteration in the Santiaguito lava dome complex, Guatemala: implications for dome collapse hazards

Science.gov (United States)

Ball, Jessica L.; Calder, Eliza S.; Hubbard, Bernard E.; Bernstein, Marc L.

2013-01-01

A combination of field mapping, geochemistry, and remote sensing methods has been employed to determine the extent of hydrothermal alteration and assess the potential for failure at the Santiaguito lava dome complex, Guatemala. The 90-year-old complex of four lava domes has only experienced relatively small and infrequent dome collapses in the past, which were associated with lava extrusion. However, existing evidence of an active hydrothermal system coupled with intense seasonal precipitation also presents ideal conditions for instability related to weakened clay-rich edifice rocks. Mapping of the Santiaguito dome complex identified structural features related to dome growth dynamics, potential areas of weakness related to erosion, and locations of fumarole fields. X-ray diffraction and backscattered electron images taken with scanning electron microscopy of dacite and ash samples collected from around fumaroles revealed only minor clay films, and little evidence of alteration. Mineral mapping using ASTER and Hyperion satellite images, however, suggest low-temperature (<150 °C) silicic alteration on erosional surfaces of the domes, but not the type of pervasive acid-sulfate alteration implicated in collapses of other altered edifices. To evaluate the possibility of internal alteration, we re-examined existing aqueous geochemical data from dome-fed hot springs. The data indicate significant water–rock interaction, but the Na–Mg–K geoindicator suggests only a short water residence time, and δ18O/δD ratios show only minor shifts from the meteoric water line with little precipitation of secondary (alteration) minerals. Based on available data, hydrothermal alteration on the dome complex appears to be restricted to surficial deposits of hydrous silica, but the study has highlighted, importantly, that the 1902 eruption crater headwall of Santa María does show more advanced argillic alteration. We also cannot rule out the possibility of advanced alteration

Consumerism and consumer complexity: implications for university teaching and teaching evaluation.

Science.gov (United States)

Hall, Wendy A

2013-07-01

A contemporary issue is the effects of a corporate production metaphor and consumerism on university education. Efforts by universities to attract students and teaching strategies aimed at 'adult learners' tend to treat student consumers as a homogeneous group with similar expectations. In this paper, I argue that consumer groups are not uniform. I use Dagevos' theoretical approach to categorize consumers as calculating, traditional, unique, and responsible. Based on the characteristics of consumers occupying these categories, I describe the implications of the varying consumer expectations for teaching. I also consider the implications for evaluation of teaching and call for research taking consumer types into account when evaluating teaching. Copyright © 2013 Elsevier Ltd. All rights reserved.

Rational Design in Catalysis: A Mechanistic Study of β-Hydride Eliminations in Gold(I) and Gold(III) Complexes Based on Features of the Reaction Valley.

Science.gov (United States)

Castiñeira Reis, Marta; López, Carlos Silva; Kraka, Elfi; Cremer, Dieter; Faza, Olalla Nieto

2016-09-06

β-Hydride eliminations for ethylgold(III) dichloride complexes are identified as reactions with an unusually long prechemical stage corresponding to the conformational preparation of the reaction complex and spanning six phases. The prechemical process is characterized by a geared rotation of the L-Au-L group (L = Cl) driving methyl group rotation and causing a repositioning of the ligands. This requires more than 28 kcal/mol of the total barrier of 34.0 kcal/mol, according to the unified reaction valley approach, which also determines that the energy requirements of the actual chemical process leading to the β-elimination product are only about 5.5 kcal/mol. A detailed mechanistic analysis was used as a basis for a rational design of substrates (via substituents on the ethyl group) and/or ligands, which can significantly reduce the reaction barrier. This strategy takes advantage of either a higher trans activity of the ligands or a tuned electronic demand of the ethyl group. The β-hydride elimination of gold(I) was found to suffer from strong Coulomb and exchange repulsion when a positively charged hydrogen atom enforces a coordination position in a d(10)-configured gold atom, thus triggering an unassisted σ-π Au(I)-C conversion.

Selective extraction and detection of noble metal based on ionic ...

Indian Academy of Sciences (India)

ClPrNTf2) was developed for selective detection of gold(III) by use of inductively coupled ... The importance to develop pre- ... attention. Ionic liquids (ILs) immobilized onto SG have been successfully applied as solid phase adsorbents for.

Structure and bonding in gold compounds

International Nuclear Information System (INIS)

Parish, R.V.

1988-01-01

Recent developments in chemical applications of 197 Au Moessbauer spectroscopy are reviewed. For gold(I) and gold(III), systematic variations in isomer shift and quadrupole splitting are seen as the ligands are changed; the effects of change in coordination number of the gold atoms are also systematic. Data for gold(II) systems involving gold-gold bonds lie between those for corresponding gold(I) and gold(III) materials, showing a small increase in isomer shift and a larger increase in quadrupole splitting as the oxidation state decreases; these trends are explained in terms of the structures. Data for mixed-metal cluster compounds are much more sensitive to structural effects than in homonuclear clusters. Both sets of data show systematic changes with increase in the number of metal atoms to which the gold atom is bound. The connectivity also influences the recoil-free fraction. (orig.)

SUBJECT INDEX

Indian Academy of Sciences (India)

Selective adsorbent for the extraction and detection of gold(III) 327. Austenitic steel .... Ru3+): catalytic effects for the reduction of 2- or 4-nitroanilines in water. 1651 ...... Leakage current transport mechanisms of La0.67Sr0.33MnO3/.

Interdisciplinary conflict and organizational complexity.

Science.gov (United States)

Guy, M E

1986-01-01

Most people think that conflict among the professional staff is inevitable and results from each profession's unique set of values. Each profession then defends itself by claiming its own turf. This article demonstrates that organizational complexity, not professional territorialism, influences the amount of intraorganizational conflict. In a comparison of two psychiatric hospitals, this study shows that there is not necessarily greater conflict across professions than within professions. However, there is a significantly greater amount of conflict among staff at a structurally more complex hospital than at a less-complex hospital, regardless of profession. Implications for management are discussed.

Determinants of Hospital Casemix Complexity

Science.gov (United States)

Becker, Edmund R.; Steinwald, Bruce

1981-01-01

Using the Commission on Professional and Hospital Activities' Resource Need Index as a measure of casemix complexity, this paper examines the relative contributions of teaching commitment and other hospital characteristics, hospital service and insurer distributions, and area characteristics to variations in casemix complexity. The empirical estimates indicate that all three types of independent variables have a substantial influence. These results are discussed in light of recent casemix research as well as current policy implications. PMID:6799430

The clinical educator and complexity: a review.

Science.gov (United States)

Schoo, Adrian; Kumar, Koshila

2018-02-08

Complexity science perspectives have helped in examining fundamental assumptions about learning and teaching in the health professions. The implications of complexity thinking for how we understand the role and development of the clinical educator is less well articulated. This review article outlines: the key principles of complexity science; a conceptual model that situates the clinical educator in a complex system; and the implications for the individual, organisation and the system. Our conceptual model situates the clinical educator at the centre of a complex and dynamic system spanning four domains and multiple levels. The four domains are: personal (encompassing personal/professional needs and expectations); health services (health agencies and their consumers); educational (educational institutions and their health students); and societal (local community/region and government). The system also comprises: micro or individual, meso or organisational, and macro or socio-political levels. Our model highlights that clinical educators are situated within a complex system comprising different agents and connections. It emphasises that individuals, teams and organisations need to recognise and be responsive to the unpredictability, interconnectedness and evolving nature of this system. Importantly, our article also calls for an epistemological shift from faculty development to capacity building in health professions education, aimed at developing individual, team, organisational and system capabilities to work with(in) complexity. Clinical educators are situated within a complex system comprising different agents and connections. © 2018 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Biodegradation of metal citrate complexes and implications for toxic-metal mobility

International Nuclear Information System (INIS)

Francis, A.J.; Dodge, C.J.; Gillow, J.B.

1992-01-01

The presence of synthetic and naturally occurring chelating agents in nuclear and toxic-metal wastes is a major concern because of their potential to enhance mobilization of metal ions away from the disposal sites. Of particular interest is citric acid, which is present in low-level and transuranic radioactive wastes and in domestic and industrial wastes (as washing fluids, for instance), as well as being found naturally. Citrate ions form multidentate, stable complexes with a variety of toxic metals and radionuclides; but biodegradation of these complexes, precipitating the metal ions as insoluble hydroxides, oxides or other salts, may retard migration. Here we report a study of the biodegradation of citrate complexes of Ca, Fe(II), Fe(III), Cd, Cu, Ni, Pb and U. Several of these complexes were not readily degraded by bacteria, and the biodegradability depended on the chemical nature of the complex, not on the toxicity of the metal to the bacteria. This resistance to biodegradation implies that citrate complexation may play an important part in migration of these hazardous wastes. (author)

Post-structuralism, Complexity and Poetics.

OpenAIRE

Dillon, Michael

2000-01-01

Post-structuralism and complexity are plural and diverse modes of thought that share a common subscription to the �anteriority of radical relationality�. They nonetheless subscribe to a different ethic of life because they address the anteriority of radical relationality in different ways. Complexity remains strategic in its bid to become a power-knowledge of the laws of becoming. It derives that strategic ethic from its scientific interest in the implicate order of non-linearity that is ...

An evaluation of factors influencing pore pressure in accretionary complexes: Implications for taper angle and wedge mechanics

Science.gov (United States)

Saffer, D.M.; Bekins, B.A.

2006-01-01

At many subduction zones, accretionary complexes form as sediment is off-scraped from the subducting plate. Mechanical models that treat accretionary complexes as critically tapered wedges of sediment demonstrate that pore pressure controls their taper angle by modifying basal and internal shear strength. Here, we combine a numerical model of groundwater flow with critical taper theory to quantify the effects of sediment and de??collement permeability, sediment thickness, sediment partitioning between accretion and underthrusting, and plate convergence rate on steady state pore pressure. Our results show that pore pressure in accretionary wedges can be viewed as a dynamically maintained response to factors which drive pore pressure (source terms) and those that limit flow (permeability and drainage path length). We find that sediment permeability and incoming sediment thickness are the most important factors, whereas fault permeability and the partitioning of sediment have a small effect. For our base case model scenario, as sediment permeability is increased, pore pressure decreases from near-lithostatic to hydrostatic values and allows stable taper angles to increase from ??? 2.5?? to 8??-12.5??. With increased sediment thickness in our models (from 100 to 8000 m), increased pore pressure drives a decrease in stable taper angle from 8.4??-12.5?? to 15?? to <4??) with increased sediment thickness (from <1 to 7 km). One key implication is that hydrologic properties may strongly influence the strength of the crust in a wide range of geologic settings. Copyright 2006 by the American Geophysical Union.

Measuring the Complexity of Urban Form and Design

OpenAIRE

Boeing, Geoff

2017-01-01

Complex systems have become a popular lens for conceptualizing cities, and complexity has substantial implications for urban performance and resilience. This paper develops a typology of methods and measures for assessing the complexity of the built form at the scale of urban design. It extends quantitative methods from urban planning, network science, ecosystems studies, fractal geometry, and information theory to the physical urban form and the analysis of qualitative human experience. Metr...

Practical implications of 'postmodern philosophy'

Directory of Open Access Journals (Sweden)

Savić Mile V.

2002-01-01

Full Text Available The article examines the implications of the discourse about postmodernity. Postmodernity is analyzed as a complex discursive figure. Within the discourse about postmodernity three levels are distinguished: the postmodern condition, postmodernism, and reflection of the postmodern condition. Special attention is paid to globalization and the problem of the enforcement of modern projects in East-European societies, particularly Serbia. These societies are termed object-societies, while their modification of modernity is called eastmodernity. The author's answer to the complexity of the postmodern condition is a conception of the politics of subsistence.

Complexity, flow, and antifragile healthcare systems: implications for nurse executives.

Science.gov (United States)

Clancy, Thomas R

2015-04-01

As systems evolve over time, their natural tendency is to become increasingly more complex. Studies in the field of complex systems have generated new perspectives on the application of management strategies in health systems. Much of this research appears as a natural extension of the cross-disciplinary field of systems theory. In this article, I further discuss the concept of fragility, its impact on system behavior, and ways to reduce it.

Managing uncertainty for sustainability of complex projects

DEFF Research Database (Denmark)

Brink, Tove

2017-01-01

Purpose – The purpose of this paper is to reveal how management of uncertainty can enable sustainability of complex projects. Design/methodology/approach – The research was conducted from June 2014 to May 2015 using a qualitative deductive approach among operation and maintenance actors in offshore...... wind farms. The research contains a focus group interview with 11 companies, 20 individual interviews and a seminar presenting preliminary findings with 60 participants. Findings – The findings reveal the need for management of uncertainty through two different paths. First, project management needs...... to join efforts. Research limitations/implications – Further research is needed to reveal the generalisability of the findings in other complex project contexts containing “unknown unknowns”. Practical implications – The research leads to the development of a tool for uncertainty management...

Molecular complexity from polyunsaturated substrates: the gold catalysis approach.

Science.gov (United States)

Fensterbank, Louis; Malacria, Max

2014-03-18

Over the last two decades, electrophilic catalysis relying on platinum(II), gold(I), and gold(III) salts has emerged as a remarkable synthetic methodology. Chemists have discovered a large variety of organic transformations that convert a great assortment of highly functionalized precursors into valuable final products. In many cases, these methodologies offer unique features, allowing access to unprecedented molecular architectures. Due to the mild reaction conditions and high function compatibility, scientists have successfully developed applications in total synthesis of natural products, as well as in asymmetric catalysis. In addition, all these developments have been accompanied by the invention of well-tailored catalysts, so that a palette of different electrophilic agents is now commercially available or readily synthesized at the bench. In some respects, researchers' interests in developing homogeneous gold catalysis can be compared with the Californian gold rush of the 19th century. It has attracted into its fervor thousands of scientists, providing a huge number of versatile and important reports. More notably, it is clear that the contribution to the art of organic synthesis is very valuable, though the quest is not over yet. Because they rely on the intervention of previously unknown types of intermediates, new retrosynthetic disconnections are now possible. In this Account, we discuss our efforts on the use of readily available polyunsaturated precursors, such as enynes, dienynes, allenynes, and allenenes to give access to highly original polycyclic structures in a single operation. These transformations transit via previously undescribed intermediates A, B, D, F, and H that will be encountered later on. All these intermediates have been determined by both ourselves and others by DFT calculations and in some cases have been confirmed on the basis of experimental data. In addition, dual gold activation can be at work in some of these transformations

A human phenome-interactome network of protein complexes implicated in genetic disorders

DEFF Research Database (Denmark)

Hansen, Kasper Lage; Karlberg, Erik, Olof, Linnart; Størling, Zenia, Marian

2007-01-01

the known disease-causing protein as the top candidate, and in 870 intervals with no identified disease-causing gene, provides novel candidates implicated in disorders such as retinitis pigmentosa, epithelial ovarian cancer, inflammatory bowel disease, amyotrophic lateral sclerosis, Alzheimer disease, type...

Toxicological evaluation of complex industrial wastes: Implications for exposure assessment

Energy Technology Data Exchange (ETDEWEB)

DeMarini, D.M.; Gallagher, J.E.; Houk, V.S.; Simmons, J.E.

1989-01-01

A variety of short-term bioassays to construct a battery of tests that could be used for assessing the biological effects of potentially hazardous complex industrial wastes were evaluated. Ten samples were studied for hepatotoxicity: These samples and an additional five were studied for mutagenicity. Although the data are limited to these samples, the results suggest that the Salmonella assay (either TA98 or TA100) or a prophage-induction assay (both in the presence of S9) in combination with determination of relative liver weight and levels of a set of serum enzymes in rats would provide a battery of tests suitable to characterize complex industrial wastes for mutagenic and hepatotoxic potential. The biological activities exhibited by the wastes were not readily predicted by the chemical profiles of the wastes, emphasizing the importance of characterizing potentially hazardous complex industrial wastes by both chemical and biological means.

Organic geochemistry of deep ground waters from the Palo Duro Basin, Texas: implications for radionuclide complexation, ground-water origin, and petroleum exploration

International Nuclear Information System (INIS)

Means, J.L.; Hubbard, N.J.

1985-05-01

This report describes the organic geochemistry of 11 ground-water samples from the Palo Duro Basin, Texas and discusses the implications of their organic geochemical compositions in terms of radionuclide complexation, ground-water origin, and the petroleum potential of two candidate repository sites in Deaf Smith and Swisher Counties. Short-chain aliphatic acid anions are the principal organic constituents present. Stability constant data and simple chemical equilibria calculations suggest that short-chain aliphatic acids are relatively weak complexing agents. The extent of complexation of a typical actinide by selected inorganic ligands present in these brines is expected to far outweigh actinide complexation by the aliphatic acid anions. Various lines of evidence suggest that some portion of the bromide concentrations in the brines is derived from the same source as the short-chain aliphatic acid anions. When the postulated organic components are subtracted from total bromide concentrations, the origins of the Palo Duro brines, based on chloride versus bromide relationships, appear largely consistent with origins based on isotopic evidence. The short-chain aliphatic acid anion content of the Palo Duro brines is postulated to have been much greater in the geologic past. Aliphatic acid anions are but one of numerous petroleum proximity indicators, which consistently suggest a greater petroleum exploration potential for the area surrounding the Swisher County site than the region encompassing the candidate site in Deaf Smith County. Short-chain aliphatic acid anions appear to provide a useful petroleum exploration tool as long as the complex reactions that may dimish their concentrations in ground water are recognized. 71 refs., 10 figs., 10 tabs

Synthesis and characterization of dihexyldithiocarbamate as a chelating agent in extraction of gold(III)

Energy Technology Data Exchange (ETDEWEB)

Fatimah, Soja Siti, E-mail: soja-sf@upi.edu [Departemen Pendidikan Kimia, Universitas Pendidikan Indonesia, Jl. Dr. Setiabudhi No. 229, Bandung 40154 (Indonesia); Department of Chemistry, Faculty of Mathematics and Natural Sciences, Padjadjaran University, Jl. Raya Bandung-Sumedang, Km. 21, Jatinangor (Indonesia); Bahti, Husein H.; Hastiawan, Iwan [Department of Chemistry, Faculty of Mathematics and Natural Sciences, Padjadjaran University, Jl. Raya Bandung-Sumedang, Km. 21, Jatinangor (Indonesia); Permanasari, Anna [Departemen Pendidikan Kimia, Universitas Pendidikan Indonesia, Jl. Dr. Setiabudhi No. 229, Bandung 40154 (Indonesia)

2016-02-08

The use of dialkyldithiocarbamates as chelating agents of transition metals have been developing for decades. Many chelating agents have been synthesized and used in the extraction of the metals. Studies on particular aspects of extraction of the metals, such as the effect of increasing hydrophobicity of chelating agents on the effectiveness of the extraction, have been done. However, despite the many studies on the synthesis and applications of this type of chelating agents, interests in the aspect of molecular structure of the synthesized ligands and of their complexes, have been limited. This study aimed at synthesizing and characterizing dihexylthiocarbamate, and using the ligand for the extraction of gold III). Characterization of the ligand and of its metal complex were done by using elemental analysis, DTG, and spectroscopic methods to include NMR, ({sup 1}H, and {sup 13}C), FTIR, and MS-ESI. Data on the synthesis, characterization, and the application of the ligand as a chelating agent are presented.

Synthesis and characterization of dihexyldithiocarbamate as a chelating agent in extraction of gold(III)

Science.gov (United States)

Fatimah, Soja Siti; Bahti, Husein H.; Hastiawan, Iwan; Permanasari, Anna

2016-02-01

The use of dialkyldithiocarbamates as chelating agents of transition metals have been developing for decades. Many chelating agents have been synthesized and used in the extraction of the metals. Studies on particular aspects of extraction of the metals, such as the effect of increasing hydrophobicity of chelating agents on the effectiveness of the extraction, have been done. However, despite the many studies on the synthesis and applications of this type of chelating agents, interests in the aspect of molecular structure of the synthesized ligands and of their complexes, have been limited. This study aimed at synthesizing and characterizing dihexylthiocarbamate, and using the ligand for the extraction of gold III). Characterization of the ligand and of its metal complex were done by using elemental analysis, DTG, and spectroscopic methods to include NMR, (1H, and 13C), FTIR, and MS-ESI. Data on the synthesis, characterization, and the application of the ligand as a chelating agent are presented.

Spacecraft Complexity Subfactors and Implications on Future Cost Growth

Science.gov (United States)

Leising, Charles J.; Wessen, Randii; Ellyin, Ray; Rosenberg, Leigh; Leising, Adam

2013-01-01

During the last ten years the Jet Propulsion Laboratory has used a set of cost-risk subfactors to independently estimate the magnitude of development risks that may not be covered in the high level cost models employed during early concept development. Within the last several years the Laboratory has also developed a scale of Concept Maturity Levels with associated criteria to quantitatively assess a concept's maturity. This latter effort has been helpful in determining whether a concept is mature enough for accurate costing but it does not provide any quantitative estimate of cost risk. Unfortunately today's missions are significantly more complex than when the original cost-risk subfactors were first formulated. Risks associated with complex missions are not being adequately evaluated and future cost growth is being underestimated. The risk subfactor process needed to be updated.

Trauma complexo e suas implicações diagnósticas Complex trauma and diagnostic implications

Directory of Open Access Journals (Sweden)

Thiago Wendt Viola

2011-01-01

was to review the definition of trauma, presenting the concept of complex trauma and investigating its clinical implications and the diagnostic categories deriving from this construct. Important questions are raised about differences between complex trauma and PTSD, followed by an investigation of PTSD symptoms and comorbid disorders, as well as the limitations of PTSD diagnosis. Taking into consideration the psychopathological impact associated with complex trauma, the article discusses the possibility of including a new diagnostic category in the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders is discussed, as part of the spectrum of post-traumatic psychopathologies.

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African Journals Online (AJOL)

metallic guld, gold oxide and gold(III) solutions in hydrochloric and sulphuric acids. Moreover ... incorporation of a solid sample of the element in a carbon paste electrode. ... closed cell containing hydrochloric or sulphuric acid as electrolyte. .... Near 265 mV is observed a quasi-reversible electrochemical system linked to the.

Research teams as complex systems: implications for knowledge management

NARCIS (Netherlands)

Vasileiadou, E.

2012-01-01

The recent increase in research collaboration creates the need to better understand the interaction between individual researchers and the collaborative team. The paper elaborates the conceptualisation of research teams as complex systems which emerge out of the local interactions of individual

Ecosystemic Complexity Theory of Conflict: Understanding the Fog of Conflict

Science.gov (United States)

Brack, Greg; Lassiter, Pamela S.; Hill, Michele B.; Moore, Sarah A.

2011-01-01

Counselors often engage in conflict mediation in professional practice. A model for understanding the complex and subtle nature of conflict resolution is presented. The ecosystemic complexity theory of conflict is offered to assist practitioners in navigating the fog of conflict. Theoretical assumptions are discussed with implications for clinical…

Traffic Dynamics on Complex Networks: A Survey

Directory of Open Access Journals (Sweden)

Shengyong Chen

2012-01-01

Full Text Available Traffic dynamics on complex networks are intriguing in recent years due to their practical implications in real communication networks. In this survey, we give a brief review of studies on traffic routing dynamics on complex networks. Strategies for improving transport efficiency, including designing efficient routing strategies and making appropriate adjustments to the underlying network structure, are introduced in this survey. Finally, a few open problems are discussed in this survey.

Philosophy of complex systems

CERN Document Server

2011-01-01

The domain of nonlinear dynamical systems and its mathematical underpinnings has been developing exponentially for a century, the last 35 years seeing an outpouring of new ideas and applications and a concomitant confluence with ideas of complex systems and their applications from irreversible thermodynamics. A few examples are in meteorology, ecological dynamics, and social and economic dynamics. These new ideas have profound implications for our understanding and practice in domains involving complexity, predictability and determinism, equilibrium, control, planning, individuality, responsibility and so on. Our intention is to draw together in this volume, we believe for the first time, a comprehensive picture of the manifold philosophically interesting impacts of recent developments in understanding nonlinear systems and the unique aspects of their complexity. The book will focus specifically on the philosophical concepts, principles, judgments and problems distinctly raised by work in the domain of comple...

SWI/SNF complex in disorder

Science.gov (United States)

Santen, Gijs W.E.; Kriek, Marjolein; van Attikum, Haico

2012-01-01

Heterozygous germline mutations in components of switch/sucrose nonfermenting (SWI/SNF) chromatin remodeling complexes were recently identified in patients with non-syndromic intellectual disability, Coffin-Siris syndrome and Nicolaides-Baraitser syndrome. The common denominator of the phenotype of these patients is severe intellectual disability and speech delay. Somatic and germline mutations in SWI/SNF components were previously implicated in tumor development. This raises the question whether patients with intellectual disability caused by SWI/SNF mutations in the germline are exposed to an increased risk of developing cancer. Here we compare the mutational spectrum of SWI/SNF components in intellectual disability syndromes and cancer, and discuss the implications of the results of this comparison for the patients. PMID:23010866

Gold(III)-Catalyzed Hydration of Phenylacetylene

Science.gov (United States)

Leslie, J. Michelle; Tzeel, Benjamin A.

2016-01-01

A guided inquiry-based experiment exploring the regioselectivity of the hydration of phenylacetylene is described. The experiment uses an acidic gold(III) catalyst in a benign methanol/water solvent system to introduce students to alkyne chemistry and key principles of green chemistry. The experiment can be easily completed in approximately 2 h,…

Preservation of NOM-metal complexes in a modern hyperalkaline stalagmite: Implications for speleothem trace element geochemistry

Science.gov (United States)

Hartland, Adam; Fairchild, Ian J.; Müller, Wolfgang; Dominguez-Villar, David

2014-03-01

true partition coefficient (Kd actual) is significantly higher. Importantly, the Kd of NOM-metal complexes [organic carbon-metal ratio) approaches 1 for the most stable aqueous complexes, as is shown here for Co, but has values of 24-150 for V, Ni and Cu. This implies that ternary surface complexation (metal-ligand co-adsorption) can occur (as for NOM-Co), but is the exception rather than the rule. We also demonstrate the potential for trace metals to record information on NOM composition as expressed through changing NOM-metal complexation patterns in dripwaters. Therefore, a suite of trace metals in stalagmites show variations clearly attributable to changes in organic ligand concentration and composition, and which potentially reflect the state of overlying surface ecosystems. The heterogeneous speciation and size distribution of aqueous NOM and metals (Lead and Wilkinson, 2006; Aiken et al., 2011). The variability in NOM-metal transport in caves that arises from the interaction between infiltration, flow routing, and the hydrodynamic properties of the fine colloids and particulates (Hartland et al., 2012). Variable dissociation kinetics through time as a function of (a) (Hartland et al., 2011). The surface charge of calcite and the availability of CaCO3 lattice sites as well as increased incidence of crystallographic defects with implications for incorporation of a range of trace species (Fairchild and Treble, 2009; Fairchild and Hartland, 2010). Thus, incorporation in speleothem calcite with consistent surface site properties will be determined by: The size and composition (i.e. hydrophilicity/hydrophobicity) of the NOM ligand, affecting adsorption and stability at the calcite surface. The lability (i.e. exchangeability) of the complexed metal and its binding affinity for the calcite surface. The concentration of aqueous complexes. Given the complexities, a partitioning approach to the problem is appropriate as a first approximation rather than a precise

Implications of the behavioral approach to hypnosis.

Science.gov (United States)

Starker, S

1975-07-01

The findings of behaviorally oriented research regarding the importance of cognitive-motivational variables in hypnosis are examined and some clinical and theoretical implications are explored. Hypnosis seems usefully conceptualized as a complex configuration or gestalt of interacting variables on several different levels, for example, cognitive, motivational, social, physiologic.

Electrospray ionization mass spectrometry for the hydrolysis complexes of cisplatin: implications for the hydrolysis process of platinum complexes.

Science.gov (United States)

Feifan, Xie; Pieter, Colin; Jan, Van Bocxlaer

2017-07-01

Non-enzyme-dependent hydrolysis of the drug cisplatin is important for its mode of action and toxicity. However, up until today, the hydrolysis process of cisplatin is still not completely understood. In the present study, the hydrolysis of cisplatin in an aqueous solution was systematically investigated by using electrospray ionization mass spectrometry coupled to liquid chromatography. A variety of previously unreported hydrolysis complexes corresponding to monomeric, dimeric and trimeric species were detected and identified. The characteristics of the Pt-containing complexes were investigated by using collision-induced dissociation (CID). The hydrolysis complexes demonstrate distinctive and correlative CID characteristics, which provides tools for an informative identification. The most frequently observed dissociation mechanism was sequential loss of NH 3 , H 2 O and HCl. Loss of the Pt atom was observed as the final step during the CID process. The formation mechanisms of the observed complexes were explored and experimentally examined. The strongly bound dimeric species, which existed in solution, are assumed to be formed from the clustering of the parent compound and its monohydrated or dihydrated complexes. The role of the electrospray process in the formation of some of the observed ions was also evaluated, and the electrospray ionization-related cold clusters were identified. The previously reported hydrolysis equilibria were tested and subsequently refined via a hydrolysis study resulting in a renewed mechanistic equilibrium system of cisplatin as proposed from our results. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

The Implications of Complex Adaptive Systems Theory for C2

National Research Council Canada - National Science Library

Grisogono, Anne-Marie

2006-01-01

.... We have been researching how application of a CAS perspective to the most pressing and complex problems that defence faces can provide more effective tools and techniques to enable higher levels...

Gold-Based Medicine: A Paradigm Shift in Anti-Cancer Therapy?

Science.gov (United States)

Yeo, Chien Ing; Ooi, Kah Kooi; Tiekink, Edward R T

2018-06-11

A new era of metal-based drugs started in the 1960s, heralded by the discovery of potent platinum-based complexes, commencing with cisplatin [(H₃N)₂PtCl₂], which are effective anti-cancer chemotherapeutic drugs. While clinical applications of gold-based drugs largely relate to the treatment of rheumatoid arthritis, attention has turned to the investigation of the efficacy of gold(I) and gold(III) compounds for anti-cancer applications. This review article provides an account of the latest research conducted during the last decade or so on the development of gold compounds and their potential activities against several cancers as well as a summary of possible mechanisms of action/biological targets. The promising activities and increasing knowledge of gold-based drug metabolism ensures that continued efforts will be made to develop gold-based anti-cancer agents.

Adaptive practices in heart failure care teams: implications for patient-centered care in the context of complexity

Directory of Open Access Journals (Sweden)

Tait GR

2015-08-01

member and could extend to other settings. Conclusion: Adaptive practices emerged unpredictably and were variably experienced by team members. Our study offers an empirically grounded explanation of how HF care teams self-organize and how adaptive practices emerge from nonlinear interdependencies among diverse agents. We use these insights to reframe the question of palliative care integration, to ask how best to foster palliative care-aligned adaptive practices in HF care. This work has implications for health care’s growing challenge of providing care to those with chronic medical illness in complex, team-based settings. Keywords: palliative care, qualitative, complex adaptive system, multimorbidity, health care teams

Binding of properdin to solid-phase immune complexes

DEFF Research Database (Denmark)

Junker, A; Baatrup, G; Svehag, S E

1998-01-01

The capacity of serum to support deposition of C3, properdin and factor B was studied by enzyme-linked immunosorbent assay using solid-phase immune complexes (IC) for activation of complement. Deposition of C3 and properdin occurred in fairly dilute normal human serum (NHS), but factor B uptake...... fixed to IC was the principal ligand for properdin in the assay. The findings could have biological implications relating to complement-mediated modification of immune complexes in disease....

The Complexity Turn in Studies of Organisations and Leadership: Relevance and Implications

Science.gov (United States)

Johannessen, Stig O.

2009-01-01

The widespread experience of complexity is the experience of radical unpredictability and loss of clear connections between cause and effect. The typical response from leaders and researchers is to suggest that more complex contexts require new ways of management control and that particular ways of organising and leading are better than others in…

Positive feelings facilitate working memory and complex decision making among older adults.

Science.gov (United States)

Carpenter, Stephanie M; Peters, Ellen; Västfjäll, Daniel; Isen, Alice M

2013-01-01

The impact of induced mild positive feelings on working memory and complex decision making among older adults (aged 63-85) was examined. Participants completed a computer administered card task in which participants could win money if they chose from "gain" decks and lose money if they chose from "loss" decks. Individuals in the positive-feeling condition chose better than neutral-feeling participants and earned more money overall. Participants in the positive-feeling condition also demonstrated improved working-memory capacity. These effects of positive-feeling induction have implications for affect theory, as well as, potentially, practical implications for people of all ages dealing with complex decisions.

Resolving complex chromosome structures during meiosis: versatile deployment of Smc5/6

NARCIS (Netherlands)

Verver, Dideke E.; Hwang, Grace H.; Jordan, Philip W.; Hamer, Geert

2016-01-01

The Smc5/6 complex, along with cohesin and condensin, is a member of the structural maintenance of chromosome (SMC) family, large ring-like protein complexes that are essential for chromatin structure and function. Thanks to numerous studies of the mitotic cell cycle, Smc5/6 has been implicated to

Human error mechanisms in complex work environments

International Nuclear Information System (INIS)

Rasmussen, J.

1988-01-01

Human error taxonomies have been developed from analysis of industrial incident reports as well as from psychological experiments. In this paper the results of the two approaches are reviewed and compared. It is found, in both cases, that a fairly small number of basic psychological mechanisms will account for most of the action errors observed. In addition, error mechanisms appear to be intimately related to the development of high skill and know-how in a complex work context. This relationship between errors and human adaptation is discussed in detail for individuals and organisations. The implications for system safety and briefly mentioned, together with the implications for system design. (author)

Human error mechanisms in complex work environments

International Nuclear Information System (INIS)

Rasmussen, Jens; Danmarks Tekniske Hoejskole, Copenhagen)

1988-01-01

Human error taxonomies have been developed from analysis of industrial incident reports as well as from psychological experiments. In this paper the results of the two approaches are reviewed and compared. It is found, in both cases, that a fairly small number of basic psychological mechanisms will account for most of the action errors observed. In addition, error mechanisms appear to be intimately related to the development of high skill and know-how in a complex work context. This relationship between errors and human adaptation is discussed in detail for individuals and organisations. The implications for system safety are briefly mentioned, together with the implications for system design. (author)

Searching for Order Within Chaos: Complexity Theorys Implications to Intelligence Support During Joint Operational Planning

Science.gov (United States)

2017-06-09

joint operational planning . 15. SUBJECT TERMS Complexity Theory , Complex Systems Theory , Complex Adaptive Systems, Dynamical Systems, Joint...complexity theory to analyze military problems and increase joint staff understanding of the operational environment during joint operational planning ?” the...13). Complex Systems Theory : “the study of the behavior of [complex adaptive] systems” (Ilachinski 2004, 4). For the purpose of this thesis there is

The complex patient: A concept clarification.

Science.gov (United States)

Manning, Eli; Gagnon, Marilou

2017-03-01

Over the last decade, the concept of the "complex patient" has not only been more widely used in multidisciplinary healthcare teams and across various healthcare disciplines, but it has also become more vacuous in meaning. The uptake of the concept of the "complex patient" spans across disciplines, such as medicine, nursing, and social work, with no consistent definition. We review the chronological evolution of this concept and its surrogate terms, namely "comorbidity," "multimorbidity," "polypathology," "dual diagnosis," and "multiple chronic conditions." Drawing on key principles of concept clarification, we highlight disciplinary usage in the literature published between 2005 and 2015 in health sciences, attending to overlaps and revealing nuances of the complex patient concept. Finally, we discuss the implications of this concept for practice, research, and theory. © 2017 John Wiley & Sons Australia, Ltd.

[VGKC-complex antibodies].

Science.gov (United States)

Watanabe, Osamu

2013-04-01

Various antibodies are associated with voltage-gated potassium channels (VGKCs). Representative antibodies to VGKCs were first identified by radioimmunoassays using radioisotope-labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were detected only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in patients with Morvan's syndrome and in those with a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins (for example LGI-1 and CASPR-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now commonly known as VGKC-complex antibodies. In general, LGI-1 antibodies are most commonly detected in patients with limbic encephalitis with syndrome of inappropriate secretion of antidiuretic hormone. CASPR-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. Furthermore, VGKC-complex antibodies are tightly associated with chronic idiopathic pain. Hyperexcitability of nociceptive pathways has also been implicated. These antibodies may be detected in sera of some patients with neurodegenerative diseases (for example, amyotrophic lateral sclerosis and Creutzfeldt-Jakob disease).

Controlling extreme events on complex networks

Science.gov (United States)

Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

2014-08-01

Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network ``mobile'' can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed.

Cumulative complexity: a functional, patient-centered model of patient complexity can improve research and practice.

Science.gov (United States)

Shippee, Nathan D; Shah, Nilay D; May, Carl R; Mair, Frances S; Montori, Victor M

2012-10-01

To design a functional, patient-centered model of patient complexity with practical applicability to analytic design and clinical practice. Existing literature on patient complexity has mainly identified its components descriptively and in isolation, lacking clarity as to their combined functions in disrupting care or to how complexity changes over time. The authors developed a cumulative complexity model, which integrates existing literature and emphasizes how clinical and social factors accumulate and interact to complicate patient care. A narrative literature review is used to explicate the model. The model emphasizes a core, patient-level mechanism whereby complicating factors impact care and outcomes: the balance between patient workload of demands and patient capacity to address demands. Workload encompasses the demands on the patient's time and energy, including demands of treatment, self-care, and life in general. Capacity concerns ability to handle work (e.g., functional morbidity, financial/social resources, literacy). Workload-capacity imbalances comprise the mechanism driving patient complexity. Treatment and illness burdens serve as feedback loops, linking negative outcomes to further imbalances, such that complexity may accumulate over time. With its components largely supported by existing literature, the model has implications for analytic design, clinical epidemiology, and clinical practice. Copyright © 2012 Elsevier Inc. All rights reserved.

Uranium ore deposits: geology and processing implications

International Nuclear Information System (INIS)

Belyk, C.L.

2010-01-01

There are fifteen accepted types of uranium ore deposits and at least forty subtypes readily identified around the world. Each deposit type has a unique set of geological characteristics which may also result in unique processing implications. Primary uranium production in the past decade has predominantly come from only a few of these deposit types including: unconformity, sandstone, calcrete, intrusive, breccia complex and volcanic ones. Processing implications can vary widely between and within the different geological models. Some key characteristics of uranium deposits that may have processing implications include: ore grade, uranium and gangue mineralogy, ore hardness, porosity, uranium mineral morphology and carbon content. Processing difficulties may occur as a result of one or more of these characteristics. In order to meet future uranium demand, it is imperative that innovative processing approaches and new technological advances be developed in order that many of the marginally economic traditional and uneconomic non-traditional uranium ore deposits can be exploited. (author)

Phenotypic and genotypic heterogeneity of Lynch syndrome: a complex diagnostic challenge.

Science.gov (United States)

Lynch, Henry T; Lanspa, Stephen; Shaw, Trudy; Casey, Murray Joseph; Rendell, Marc; Stacey, Mark; Townley, Theresa; Snyder, Carrie; Hitchins, Megan; Bailey-Wilson, Joan

2018-07-01

Lynch syndrome is the hereditary disorder that most frequently predisposes to colorectal cancer as well as predisposing to a number of extracolonic cancers, most prominently endometrial cancer. It is caused by germline mutations in the mismatch repair genes. Both its phenotype and genotype show marked heterogeneity. This review gives a historical overview of the syndrome, its heterogeneity, its genomic landscape, and its implications for complex diagnosis, genetic counseling and putative implications for immunotherapy.

Single-molecule force-conductance spectroscopy of hydrogen-bonded complexes

DEFF Research Database (Denmark)

Pirrotta, Alessandro; De Vico, Luca; Solomon, Gemma C.

2017-01-01

to inform about molecular recognition events at the single-molecule limit. For this, we consider the force-conductance characteristics of a prototypical class of hydrogen bonded bimolecular complexes sandwiched between gold electrodes. The complexes consist of derivatives of a barbituric acid and a Hamilton...... is mechanically manipulated. The implication is that force and conductance provide complementary information about the evolution of molecules in junctions that can be used to interrogate basic structure-transport relations at the single-molecule limit....

The complex remuneration of human resources for health in low-income settings: policy implications and a research agenda for designing effective financial incentives.

Science.gov (United States)

Bertone, Maria Paola; Witter, Sophie

2015-07-28

Human resources for health represent an essential component of health systems and play a key role to accelerate progress towards universal health coverage. Many countries in sub-Saharan Africa face challenges regarding the availability, distribution and performance of health workers, which could be in part addressed by providing effective financial incentives. Based on an overview of the existing literature, the paper highlights the gaps in the existing research in low-income countries exploring the different components of health workers' incomes. It then proposes a novel approach to the analysis of financial incentives and delineates a research agenda, which could contribute to shed light on this topic. The article finds that, while there is ample research that investigates separately each of the incomes health workers may earn (for example, salary, fee-for-service payments, informal incomes, "top-ups" and per diems, dual practice and non-health activities), there is a dearth of studies which look at the health workers' "complex remuneration", that is, the whole of the financial incentives available. Little research exists which analyses simultaneously all revenues of health workers, quantifies the overall remuneration and explores its complexity, its multiple components and their features, as well as the possible interaction between income components. However, such a comprehensive approach is essential to fully comprehend health workers' incentives, by investigating the causes (at individual and system level) of the fragmentation in the income structure and the variability in income levels, as well as the consequences of the "complex remuneration" on motivation and performance. This proposition has important policy implications in terms of devising effective incentive packages as it calls for an active consideration of the role that "complex remuneration" plays in determining recruitment, retention and motivation patterns, as well as, more broadly, the

Change in composition of the Anopheles gambiae complex and its possible implications for the transmission of malaria and lymphatic filariasis in north-eastern Tanzania

DEFF Research Database (Denmark)

Derua, Yahya A; Alifrangis, Michael; Hosea, Kenneth M

2012-01-01

ABSTRACT: BACKGROUND: A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control. ...... to differences in biology and vectorial capacity of the An. gambiae s.l. complex the change in sibling species composition will have important implications for the epidemiology and control of malaria and lymphatic filariasis in the study area.......ABSTRACT: BACKGROUND: A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control...

Media framing of complex issues: The case of endangered languages.

Science.gov (United States)

Rivenburgh, Nancy K

2013-08-01

This study investigates how media frame a global trend that is complex in nature, emergent in terms of scientific understanding, and has public policy implications: the rapid disappearance of languages. It analyzes how English-language media from 15 western, industrialized countries frame the causes and implications of endangered languages over 35 years (1971-2006) - a time period notable for growing, interdisciplinary concerns over the potential negative impacts of losing the world's linguistic diversity. The results reveal a media discourse characterized by three complementary frames that are sympathetic to the plight of endangered languages, but that present the problem, its cause, and societal implications in a logical structure that would promote public complacency.

The CH/π hydrogen bond: Implication in chemistry

Science.gov (United States)

Nishio, M.

2012-06-01

The CH/π hydrogen bond is the weakest extreme of hydrogen bonds that occurs between a soft acid CH and a soft base π-system. Implication in chemistry of the CH/π hydrogen bond includes issues of conformation, crystal packing, and specificity in host/guest complexes. The result obtained by analyzing the Cambridge Structural Database is reviewed. The peculiar axial preference of isopropyl group in α-phellandrene and folded conformation of levopimaric acid have been explained in terms of the CH/π hydrogen bond, by high-level ab initio MO calculations. Implication of the CH/π hydrogen bond in structural biology is also discussed, briefly.

Complexation and molecular modeling studies of europium(III)-gallic acid-amino acid complexes.

Science.gov (United States)

Taha, Mohamed; Khan, Imran; Coutinho, João A P

2016-04-01

With many metal-based drugs extensively used today in the treatment of cancer, attention has focused on the development of new coordination compounds with antitumor activity with europium(III) complexes recently introduced as novel anticancer drugs. The aim of this work is to design new Eu(III) complexes with gallic acid, an antioxida'nt phenolic compound. Gallic acid was chosen because it shows anticancer activity without harming health cells. As antioxidant, it helps to protect human cells against oxidative damage that implicated in DNA damage, cancer, and accelerated cell aging. In this work, the formation of binary and ternary complexes of Eu(III) with gallic acid, primary ligand, and amino acids alanine, leucine, isoleucine, and tryptophan was studied by glass electrode potentiometry in aqueous solution containing 0.1M NaNO3 at (298.2 ± 0.1) K. Their overall stability constants were evaluated and the concentration distributions of the complex species in solution were calculated. The protonation constants of gallic acid and amino acids were also determined at our experimental conditions and compared with those predicted by using conductor-like screening model for realistic solvation (COSMO-RS) model. The geometries of Eu(III)-gallic acid complexes were characterized by the density functional theory (DFT). The spectroscopic UV-visible and photoluminescence measurements are carried out to confirm the formation of Eu(III)-gallic acid complexes in aqueous solutions. Copyright © 2016 Elsevier Inc. All rights reserved.

The role of different network modifying cations on the speciation of the Co2 + complex in silicates and implication in the investigation of historical glasses

Science.gov (United States)

Fornacelli, Cristina; Ceglia, Andrea; Bracci, Susanna; Vilarigues, Marcia

2018-01-01

In the last decades the speciation of the cobalt complex in a glass matrix has been extensively studied. Bivalent cobalt ions in glasses of different composition commonly adopt a tetrahedral coordination, though hexa- or penta-coordinated species are also possible. Changes in the absorbance spectrum of Co-doped glasses were attested in previous studies according to the introduction of different modifying cations. A shifting of the first sub-band characterizing the typical triplets of tetrahedral Co2 + ions in both the visible and near infrared regions was observed, but discrepancies in literature suggested a relevant role of glass composition on the definition of the optical signature of cobalt. Co-doped glasses with different composition (soda-lime, potash-lime, mixed alkali and ZnO-Na2O-CaO-SiO2) were studied via Fiber Optic Reflectance Spectroscopy (FORS). Pseudo-Voigt functions were used for the deconvolution of the absorbance spectra and the features of the bands characteristic of each cobalt complex were investigated. The structural role played by each modifying cation and the fundamental implications of glass basicity on the speciation of different Co-complexes were stressed. Changes in glass structure resulted in different equilibria between the three absorbing species whose specific optical signatures in the 480-530 nm region interact to determine the resulting absorbance spectrum.

Understanding complex urban systems multidisciplinary approaches to modeling

CERN Document Server

Gurr, Jens; Schmidt, J

2014-01-01

Understanding Complex Urban Systems takes as its point of departure the insight that the challenges of global urbanization and the complexity of urban systems cannot be understood – let alone ‘managed’ – by sectoral and disciplinary approaches alone. But while there has recently been significant progress in broadening and refining the methodologies for the quantitative modeling of complex urban systems, in deepening the theoretical understanding of cities as complex systems, or in illuminating the implications for urban planning, there is still a lack of well-founded conceptual thinking on the methodological foundations and the strategies of modeling urban complexity across the disciplines. Bringing together experts from the fields of urban and spatial planning, ecology, urban geography, real estate analysis, organizational cybernetics, stochastic optimization, and literary studies, as well as specialists in various systems approaches and in transdisciplinary methodologies of urban analysis, the volum...

Arp2/3 complex activity in filopodia of spreading cells

Directory of Open Access Journals (Sweden)

Mendes Paula M

2008-12-01

Full Text Available Abstract Background Cells use filopodia to explore their environment and to form new adhesion contacts for motility and spreading. The Arp2/3 complex has been implicated in lamellipodial actin assembly as a major nucleator of new actin filaments in branched networks. The interplay between filopodial and lamellipodial protrusions is an area of much interest as it is thought to be a key determinant of how cells make motility choices. Results We find that Arp2/3 complex localises to dynamic puncta in filopodia as well as lamellipodia of spreading cells. Arp2/3 complex spots do not appear to depend on local adhesion or on microtubules for their localisation but their inclusion in filopodia or lamellipodia depends on the activity of the small GTPase Rac1. Arp2/3 complex spots in filopodia are capable of incorporating monomeric actin, suggesting the presence of available filament barbed ends for polymerisation. Arp2/3 complex in filopodia co-localises with lamellipodial proteins such as capping protein and cortactin. The dynamics of Arp2/3 complex puncta suggests that they are moving bi-directionally along the length of filopodia and that they may be regions of lamellipodial activity within the filopodia. Conclusion We suggest that filopodia of spreading cells have regions of lamellipodial activity and that this activity affects the morphology and movement of filopodia. Our work has implications for how we understand the interplay between lamellipodia and filopodia and for how actin networks are generated spatially in cells.

CNV analysis in 169 patients with bladder exstrophy-epispadias complex

NARCIS (Netherlands)

Lowtzow, C. von; Hofmann, A.; Zhang, R.; Marsch, F.; Ebert, A.K.; Rosch, W.; Stein, R.; Boemers, T.M.; Hirsch, K.; Marcelis, C.L.M.; Feitz, W.F.J.; Brusco, A.; Migone, N.; Grazia, M. Di; Moebus, S.; Nothen, M.M.; Reutter, H.; Ludwig, M.; Draaken, M.

2016-01-01

BACKGROUND: The bladder exstrophy-epispadias complex (BEEC) represents the severe end of the congenital uro-rectal malformation spectrum. Initial studies have implicated rare copy number variations (CNVs), including recurrent duplications of chromosomal region 22q11.21, in BEEC etiology. METHODS: To

Complexity Theory and CALL Curriculum in Foreign Language Learning

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Hassan Soleimani

2014-05-01

Full Text Available Complexity theory literally indicates the complexity of a system, behavior, or a process. Its connotative meaning, while, implies dynamism, openness, sensitivity to initial conditions and feedback, and adaptation properties of a system. Regarding English as a Foreign/ Second Language (EFL/ESL this theory emphasizes on the complexity of the process of teaching and learning, including all the properties of a complex system. The purpose of the current study is to discuss the role of CALL as a modern technology in simplifying the process of teaching and learning a new language while integrating into the complexity theory. Nonetheless, the findings obtained from reviewing previously conducted studies in this field confirmed the usefulness of CALL curriculum in EFL/ESL contexts. These findings can also provide pedagogical implications for employing computer as an effective teaching and learning tool.

Discrete symmetries and the complex structure of Calabi-Yau manifolds

International Nuclear Information System (INIS)

Ross, G.G.

1988-01-01

We show how the discrete symmetries, which may be present after Calabi-Yau compactification for specific choices of the complex structure, extend to the h 2,1 moduli - the scalar fields whose vacuum expectation values determine the complex structure. This allows us to determine much about the coupling of the moduli and hence the energetically favoured complex structure. The discrete symmetry transformation properties of the moduli are worked out in detail for a three-generation Calabi-Yau model and it is shown how minimization of the effective potential involving these fields selects the complex structure which leaves unbroken a set of discrete symmetries. The phenomenological implications of the symmetries are briefly discussed. (orig.)

Advances in the genetically complex autoinflammatory diseases.

Science.gov (United States)

Ombrello, Michael J

2015-07-01

Monogenic diseases usually demonstrate Mendelian inheritance and are caused by highly penetrant genetic variants of a single gene. In contrast, genetically complex diseases arise from a combination of multiple genetic and environmental factors. The concept of autoinflammation originally emerged from the identification of individual, activating lesions of the innate immune system as the molecular basis of the hereditary periodic fever syndromes. In addition to these rare, monogenic forms of autoinflammation, genetically complex autoinflammatory diseases like the periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome, chronic recurrent multifocal osteomyelitis (CRMO), Behçet's disease, and systemic arthritis also fulfill the definition of autoinflammatory diseases-namely, the development of apparently unprovoked episodes of inflammation without identifiable exogenous triggers and in the absence of autoimmunity. Interestingly, investigations of these genetically complex autoinflammatory diseases have implicated both innate and adaptive immune abnormalities, blurring the line between autoinflammation and autoimmunity. This reinforces the paradigm of concerted innate and adaptive immune dysfunction leading to genetically complex autoinflammatory phenotypes.

Complexity, fractal dynamics and determinism in treadmill ambulation: Implications for clinical biomechanists.

Science.gov (United States)

Hollman, John H; Watkins, Molly K; Imhoff, Angela C; Braun, Carly E; Akervik, Kristen A; Ness, Debra K

2016-08-01

Reduced inter-stride complexity during ambulation may represent a pathologic state. Evidence is emerging that treadmill training for rehabilitative purposes may constrain the locomotor system and alter gait dynamics in a way that mimics pathological states. The purpose of this study was to examine the dynamical system components of gait complexity, fractal dynamics and determinism during treadmill ambulation. Twenty healthy participants aged 23.8 (1.2) years walked at preferred walking speeds for 6min on a motorized treadmill and overground while wearing APDM 6 Opal inertial monitors. Stride times, stride lengths and peak sagittal plane trunk velocities were measured. Mean values and estimates of complexity, fractal dynamics and determinism were calculated for each parameter. Data were compared between overground and treadmill walking conditions. Mean values for each gait parameter were statistically equivalent between overground and treadmill ambulation (P>0.05). Through nonlinear analyses, however, we found that complexity in stride time signals (P<0.001), and long-range correlations in stride time and stride length signals (P=0.005 and P=0.024, respectively), were reduced on the treadmill. Treadmill ambulation induces more predictable inter-stride time dynamics and constrains fluctuations in stride times and stride lengths, which may alter feedback from destabilizing perturbations normally experienced by the locomotor control system during overground ambulation. Treadmill ambulation, therefore, may provide less opportunity for experiencing the adaptability necessary to successfully ambulate overground. Investigators and clinicians should be aware that treadmill ambulation will alter dynamic gait characteristics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reaction-diffusion controlled growth of complex structures

Science.gov (United States)

Noorduin, Willem; Mahadevan, L.; Aizenberg, Joanna

2013-03-01

Understanding how the emergence of complex forms and shapes in biominerals came about is both of fundamental and practical interest. Although biomineralization processes and organization strategies to give higher order architectures have been studied extensively, synthetic approaches to mimic these self-assembled structures are highly complex and have been difficult to emulate, let alone replicate. The emergence of solution patterns has been found in reaction-diffusion systems such as Turing patterns and the BZ reaction. Intrigued by this spontaneous formation of complexity we explored if similar processes can lead to patterns in the solid state. We here identify a reaction-diffusion system in which the shape of the solidified products is a direct readout of the environmental conditions. Based on insights in the underlying mechanism, we developed a toolbox of engineering strategies to deterministically sculpt patterns and shapes, and combine different morphologies to create a landscape of hierarchical multi scale-complex tectonic architectures with unprecedented levels of complexity. These findings may hold profound implications for understanding, mimicking and ultimately expanding upon nature's morphogenesis strategies, allowing the synthesis of advanced highly complex microscale materials and devices. WLN acknowledges the Netherlands Organization for Scientific Research for financial support

Modeling geophysical complexity: a case for geometric determinism

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C. E. Puente

2007-01-01

Full Text Available It has been customary in the last few decades to employ stochastic models to represent complex data sets encountered in geophysics, particularly in hydrology. This article reviews a deterministic geometric procedure to data modeling, one that represents whole data sets as derived distributions of simple multifractal measures via fractal functions. It is shown how such a procedure may lead to faithful holistic representations of existing geophysical data sets that, while complementing existing representations via stochastic methods, may also provide a compact language for geophysical complexity. The implications of these ideas, both scientific and philosophical, are stressed.

The Solarya Volcano-Plutonic Complex (NW Turkey): Petrography, Petrogenesis and Tectonic Implications

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Ünal, Alp; Kamacı, Ömer; Altunkaynak, Şafak

2014-05-01

The post collisional magmatic activity produced several volcano-plutonic complexes in NW Anatolia (Turkey) during the late Oligocene- Middle Miocene. One of the major volcano-plutonic complexes, the Solarya volcano-plutonic complex is remarkable for its coeval and cogenetic plutonic (Solarya pluton), hypabysal and volcanic rocks of Early Miocene (24-21 Ma) age. Solarya pluton is an epizonal pluton which discordantly intruded into metamorphic and nonmetamorphic basement rocks of Triassic age. It is a N-S trending magmatic body covering an area of 220 km2,approximatelly 20 km in length and 10 km in width. Based on the field and petrographic studies, three main rock groups distinguished in Solarya pluton; K-feldspar megacrystalline granodiorite, microgranite-granodiorite and haplogranite. Porphyritic and graphic-granophyric textures are common in these three rock groups. Pluton contains magmatic enclaves and syn-plutonic dykes of dioritic composition. Hypabyssal rocks are represented by porphyritic microdiorite and porphyritic quartz-diorite. They form porphyry plugs, sheet inrusions and dykes around the pluton. Porphyrites have microcrystalline-cryptocrystalline groundmass displaying micrographic and granophyric textures. Petrographically similar to the hypabyssal rocks, volcanic rocks are formed from andesitic and dasitic lavas and pyroclastic rocks. Plutonic, hypabyssal and volcanic rocks of Solarya volcano-plutonic complex show similar major-trace element and Sr-Nd-Pb isotopic compositions, indicating common magmatic evolution and multicomponent melt sources including mantle and crustal components. They are mainly metaluminous, medium to high-K calc alkaline rocks and display enrichment in LILE and depletion in Nb, Ta, P and Ti. They have initial 87Sr/86Sr values of 0.70701- 0.70818 and 143Nd/144Nd values of 0.51241-0.51250. These geochemical characteristics and isotopic signatures are considered to reflect the composition of the magmas derived from a

The exocyst complex in health and disease

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Magdanela eMartin-Urdiroz

2016-04-01

Full Text Available Exocytosis involves the fusion of intracellular secretory vesicles with the PM, thereby delivering integral membrane proteins to the cell surface and releasing material into the extracellular space. Importantly, exocytosis also provides a source of lipid moieties for membrane extension. The tethering of the secretory vesicle before docking and fusion with the PM is mediated by the exocyst complex, an evolutionary conserved octameric complex of proteins. Recent findings indicate that the exocyst complex also takes part in other intra-cellular processes besides secretion. These various functions seem to converge towards defining a direction of membrane growth in a range of systems from fungi to plants and from neurons to cilia. In this review we summarise the current knowledge of exocyst function in cell polarity, signalling and cell-cell communication and discuss implications for plant and animal health and disease.

Managing the Lower Eyelid Complex in the Thick-Skinned Patient.

Science.gov (United States)

Floyd, Elizabeth Mia; Perkins, Stephen W

2018-02-01

Thick skin presents a unique set of challenges within the realm of facial plastic surgery, and addressing the lower lid complex is no exception. There are several procedures for addressing the lower lids, the first and foremost being lower lid blepharoplasty. However, the remaining procedures combined with surgical techniques have exclusive implications in thick skin. Understanding the anatomy and various techniques that can be applied to thick skin can help achieve aesthetically more pleasing results in comparison to those of thin skin. As will be discussed in this article, patients with skin color of Fitzpatrick's grade III or higher have several characteristics associated with their skin, including thicker dermis as well as different patterns of aging, which have implications for addressing the lower lid complex. The senior author has extensive experience performing lower lid procedures and seeks to impart how best to understand and adapt for these differences to allow for the best aesthetic result. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Complexity, Modeling, and Natural Resource Management

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Paul Cilliers

2013-09-01

Full Text Available This paper contends that natural resource management (NRM issues are, by their very nature, complex and that both scientists and managers in this broad field will benefit from a theoretical understanding of complex systems. It starts off by presenting the core features of a view of complexity that not only deals with the limits to our understanding, but also points toward a responsible and motivating position. Everything we do involves explicit or implicit modeling, and as we can never have comprehensive access to any complex system, we need to be aware both of what we leave out as we model and of the implications of the choice of our modeling framework. One vantage point is never sufficient, as complexity necessarily implies that multiple (independent conceptualizations are needed to engage the system adequately. We use two South African cases as examples of complex systems - restricting the case narratives mainly to the biophysical domain associated with NRM issues - that make the point that even the behavior of the biophysical subsystems themselves are already complex. From the insights into complex systems discussed in the first part of the paper and the lessons emerging from the way these cases have been dealt with in reality, we extract five interrelated generic principles for practicing science and management in complex NRM environments. These principles are then further elucidated using four further South African case studies - organized as two contrasting pairs - and now focusing on the more difficult organizational and social side, comparing the human organizational endeavors in managing such systems.

Barriers to Research and Implications for Training Counselors

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James R Ruby

2013-03-01

Full Text Available Research is an important part of quality clinical practice in the field of counseling. This study addresses the constraints that produce a gap in master’s level practitioner research among counselors in Illinois. Ninety-nine master’s level clinicians responded to surveys and answered a series of questions regarding what constrains them from being more involved in research. These respondents provided valuable feedback regarding possible recommendations for training that might encourage increased research activity for future master’s level counselors. Training improvements such as mentored research activity and training in less complex research methods were indicated. Keywords: Clinical practice, Implications, Barriers to research, less complex research

Complex terrain influences ecosystem carbon responses to temperature and precipitation

Science.gov (United States)

Reyes, W. M.; Epstein, H. E.; Li, X.; McGlynn, B. L.; Riveros-Iregui, D. A.; Emanuel, R. E.

2017-08-01

Terrestrial ecosystem responses to temperature and precipitation have major implications for the global carbon cycle. Case studies demonstrate that complex terrain, which accounts for more than 50% of Earth's land surface, can affect ecological processes associated with land-atmosphere carbon fluxes. However, no studies have addressed the role of complex terrain in mediating ecophysiological responses of land-atmosphere carbon fluxes to climate variables. We synthesized data from AmeriFlux towers and found that for sites in complex terrain, responses of ecosystem CO2 fluxes to temperature and precipitation are organized according to terrain slope and drainage area, variables associated with water and energy availability. Specifically, we found that for tower sites in complex terrain, mean topographic slope and drainage area surrounding the tower explained between 51% and 78% of site-to-site variation in the response of CO2 fluxes to temperature and precipitation depending on the time scale. We found no such organization among sites in flat terrain, even though their flux responses exhibited similar ranges. These results challenge prevailing conceptual framework in terrestrial ecosystem modeling that assumes that CO2 fluxes derive from vertical soil-plant-climate interactions. We conclude that the terrain in which ecosystems are situated can also have important influences on CO2 responses to temperature and precipitation. This work has implications for about 14% of the total land area of the conterminous U.S. This area is considered topographically complex and contributes to approximately 15% of gross ecosystem carbon production in the conterminous U.S.

Teacher Job Dissatisfaction: Implications for Teacher Sustainability and Social Transformation

Science.gov (United States)

Okeke, Chinedu I.; Mtyuda, Pamela N.

2017-01-01

Teachers play a key role in the social transformation agenda. This agentic position of the teacher implicates an agenda for sustainability programmes that position them for this complex responsibility. A qualitative case study research design was employed to obtain the perspectives of teachers on job dissatisfaction. The researchers followed a…

Complexity perspectives on clinical decision making in an intensive care unit

NARCIS (Netherlands)

De Bock, Ben A.; Willems, Dick L.; Weinstein, Henry C.

2017-01-01

How to clarify the implications of complexity thinking for decision making in the intensive care unit (ICU)? Retrospective qualitative empirical research. Practitioners in an ICU were interviewed on how their decisions were made regarding a particular patient in a difficult, clinical situation.

Ubiquitous Computing, Complexity and Culture

DEFF Research Database (Denmark)

environments, experience time, and develop identities individually and socially. Interviews with working media artists lend further perspectives on these cultural transformations. Drawing on cultural theory, new media art studies, human-computer interaction theory, and software studies, this cutting-edge book......The ubiquitous nature of mobile and pervasive computing has begun to reshape and complicate our notions of space, time, and identity. In this collection, over thirty internationally recognized contributors reflect on ubiquitous computing’s implications for the ways in which we interact with our...... critically unpacks the complex ubiquity-effects confronting us every day....

[Functional connectivity and complex networks in focal epilepsy. Pathophysiology and therapeutic implications].

Science.gov (United States)

Pastor, Jesús; Sola, Rafael G; Vega-Zelaya, Lorena; Garnes, Óscar; Ortega, Guillermo J

2014-05-01

The traditional surgical approach to treat drug-resistant focal epileptic patients is in the resection or disconnection of the epileptic focus. However, a significant minority of patients continue to experience seizures after surgery, which shows the incomplete level of knowledge that currently we have of this pathology. This paper introduces some concepts of functional connectivity and complex networks methodology with its application to the study of neurophysiological recordings from patients suffering from drug-resistant focal epilepsy. In order to fully understand the new developments in the area of complex networks and its applications to the study of epilepsy, we will here review fundamental concepts in complex networks methodology, synchronization and functional connectivity. Some of the most recent published works dealing with focal epilepsy viewed under this new perspective will be revised and commented. We think that a wider perspective in the study of epilepsy, such as the one reviewed in this work, will allow epileptologists to consider surgical alternatives in the usual treatment of focal epilepsy at those currently performed in most medical centers around the world. Combining the traditional knowledge with new insights provided by network theory will certainly fill many of the gaps we have today in the fragmented understanding of epilepsy.

Elucidating the Protonation Site of Vanadium Peroxide Complexes And the Implications for Biomimetic Catalysis

Energy Technology Data Exchange (ETDEWEB)

Schneider, C.J.; Penner-Hahn, J.E.; Pecoraro, V.L.

2009-05-27

Coordination complexes of vanadium(5+) played a key role in understanding the structure and mechanism of vanadium-dependent haloperoxidases, particularly the effects of protonation on peroxide coordination to dioxovanadium(5+) species, and in the activation of the peroxo-oxovanadium(5+) complex for substrate oxidation. There has been no spectroscopic evidence that could test the presence of a hydroxo intermediate in a catalytically active oxovanadium(5+) complex. Herein we report the use of the pre-edge transition in X-ray absorption spectroscopy as a spectroscopic signature for V{double_bond}O bonding. Displacement of oxo donors with hydrogen peroxide or chloride donors dramatically decreases the pre-edge intensity, confirming that the source of the intense pre-edge feature is closely related to the {pi}-bonding associated with the V{double_bond}O. Protonation of a catalytically active tripodal amine oxovanadium(5+) complex has no affect on the pre-edge intensity and, therefore, rules out the possibility of a hydroxo intermediate in the catalytic cycle.

Oxalate metal complexes in aerosol particles: implications for the hygroscopicity of oxalate-containing particles

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T. Furukawa

2011-05-01

Full Text Available Atmospheric aerosols have both a direct and an indirect cooling effect that influences the radiative balance at the Earth's surface. It has been estimated that the degree of cooling is large enough to weaken the warming effect of carbon dioxide. Among the cooling factors, secondary organic aerosols (SOA play an important role in the solar radiation balance in the troposphere as SOA can act as cloud condensation nuclei (CCN and extend the lifespan of clouds because of their high hygroscopic and water soluble nature. Oxalic acid is an important component of SOA, and is produced via several formation pathways in the atmosphere. However, it is not certain whether oxalic acid exists as free oxalic acid or as metal oxalate complexes in aerosols, although there is a marked difference in their solubility in water and their hygroscopicity. We employed X-ray absorption fine structure spectroscopy to characterize the calcium (Ca and zinc (Zn in aerosols collected at Tsukuba in Japan. Size-fractionated aerosol samples were collected for this purpose using an impactor aerosol sampler. It was shown that 10–60% and 20–100% of the total Ca and Zn in the finer particles (<2.1 μm were present as Ca and Zn oxalate complexes, respectively. Oxalic acid is hygroscopic and can thus increase the CCN activity of aerosol particles, while complexes with various polyvalent metal ions such as Ca and Zn are not hygroscopic, which cannot contribute to the increase of the CCN activity of aerosols. Based on the concentrations of noncomplexed and metal-complexed oxalate species, we found that most of the oxalic acid is present as metal oxalate complexes in the aerosols, suggesting that oxalic acid does not always increase the hygroscopicity of aerosols in the atmosphere. Similar results are expected for other dicarboxylic acids, such as malonic and succinic acids. Thus, it is advisable that the cooling effect of organic aerosols should be estimated by including the

Structural complexity, movement bias, and metapopulation extinction risk in dendritic ecological networks

Science.gov (United States)

Campbell Grant, Evan H.

2011-01-01

Spatial complexity in metacommunities can be separated into 3 main components: size (i.e., number of habitat patches), spatial arrangement of habitat patches (network topology), and diversity of habitat patch types. Much attention has been paid to lattice-type networks, such as patch-based metapopulations, but interest in understanding ecological networks of alternative geometries is building. Dendritic ecological networks (DENs) include some increasingly threatened ecological systems, such as caves and streams. The restrictive architecture of dendritic ecological networks might have overriding implications for species persistence. I used a modeling approach to investigate how number and spatial arrangement of habitat patches influence metapopulation extinction risk in 2 DENs of different size and topology. Metapopulation persistence was higher in larger networks, but this relationship was mediated by network topology and the dispersal pathways used to navigate the network. Larger networks, especially those with greater topological complexity, generally had lower extinction risk than smaller and less-complex networks, but dispersal bias and magnitude affected the shape of this relationship. Applying these general results to real systems will require empirical data on the movement behavior of organisms and will improve our understanding of the implications of network complexity on population and community patterns and processes.

Sustainability Assessment of a Biorefinery Complex in Thailand

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Pariyapat Nilsalab

2011-03-01

Full Text Available In this paper, a biorefinery complex in Thailand was assessed vis-à-vis sustainability. The complex studied includes plantations of sugarcane and a biorefinery system composed of several units including, a sugar mill, power plant, ethanol factory and fertilizer plant. The assessment aimed at evaluating the environmental and socio-economic implications relating to molasses-based ethanol production and use, and maximized utilization of the biomass materials produced as part of the biorefinery complex. Global warming potential, human development index and total value added are the three indicators that were selected to perform the assessment. The results obtained revealed that the maximization of biomass utilization at the level of the biorefinery complex provide greenhouse gases emissions reduction benefits, enhanced living conditions for sugarcane farmers and employees of the biorefinery, and economic benefits, particularly with regard to profit and income generation. These results could serve as a first step to further improve and design indicators for sustainability assessment of biomass utilization.

Clinical utility of seropositive voltage-gated potassium channel-complex antibody.

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Jammoul, Adham; Shayya, Luay; Mente, Karin; Li, Jianbo; Rae-Grant, Alexander; Li, Yuebing

2016-10-01

Antibodies against voltage-gated potassium channel (VGKC)-complex are implicated in the pathogenesis of acquired neuromyotonia, limbic encephalitis, faciobrachial dystonic seizure, and Morvan syndrome. Outside these entities, the clinical value of VGKC-complex antibodies remains unclear. We conducted a single-center review of patients positive for VGKC-complex antibodies over an 8-year period. Among 114 patients positive for VGKC-complex antibody, 11 (9.6%) carrying the diagnosis of limbic encephalitis (n = 9) or neuromyotonia (n = 2) constituted the classic group, and the remaining 103 cases of various neurologic and non-neurologic disorders comprised the nonclassic group. The median titer for the classic group was higher than the nonclassic group ( p 0.25 nM) VGKC-complex antibody levels ( p VGKC-complex antibody titers are more likely found in patients with classically associated syndromes and other autoimmune conditions. Low-level VGKC-complex antibodies can be detected in nonspecific and mostly nonautoimmune disorders. The presence of VGKC-complex antibody, rather than its level, may serve as a marker of malignancy.

Clinical utility of seropositive voltage-gated potassium channel–complex antibody

Science.gov (United States)

Jammoul, Adham; Shayya, Luay; Mente, Karin; Li, Jianbo; Rae-Grant, Alexander

2016-01-01

Abstract Background: Antibodies against voltage-gated potassium channel (VGKC)–complex are implicated in the pathogenesis of acquired neuromyotonia, limbic encephalitis, faciobrachial dystonic seizure, and Morvan syndrome. Outside these entities, the clinical value of VGKC-complex antibodies remains unclear. Methods: We conducted a single-center review of patients positive for VGKC-complex antibodies over an 8-year period. Results: Among 114 patients positive for VGKC-complex antibody, 11 (9.6%) carrying the diagnosis of limbic encephalitis (n = 9) or neuromyotonia (n = 2) constituted the classic group, and the remaining 103 cases of various neurologic and non-neurologic disorders comprised the nonclassic group. The median titer for the classic group was higher than the nonclassic group (p 0.25 nM) VGKC-complex antibody levels (p VGKC-complex antibody titers are more likely found in patients with classically associated syndromes and other autoimmune conditions. Low-level VGKC-complex antibodies can be detected in nonspecific and mostly nonautoimmune disorders. The presence of VGKC-complex antibody, rather than its level, may serve as a marker of malignancy. PMID:27847683

Structure of the Haro 6-5 complex

International Nuclear Information System (INIS)

Gledhill, T.M.; Warren-Smith, R.F.; Scarrott, S.M.

1986-01-01

An imaging polarization study of the Haro 6-5 complex including its emission-line jet feature is presented. The sources of illumination are identified and a geometrical interpretation for the system is suggested. In the R waveband the emission-line jet is linearly polarized at a level of 18 +- 2 per cent at PA 147 +- 8 0 , implying that it is a reflection phenomenon. The implications of this observation are discussed. (author)

Tuberous sclerosis complex surveillance and management: recommendations of the 2012 International Tuberous Sclerosis Complex Consensus Conference.

Science.gov (United States)

Krueger, Darcy A; Northrup, Hope

2013-10-01

Tuberous sclerosis complex is a genetic disorder affecting every organ system, but disease manifestations vary significantly among affected individuals. The diverse and varied presentations and progression can be life-threatening with significant impact on cost and quality of life. Current surveillance and management practices are highly variable among region and country, reflective of the fact that last consensus recommendations occurred in 1998 and an updated, comprehensive standard is lacking that incorporates the latest scientific evidence and current best clinical practices. The 2012 International Tuberous Sclerosis Complex Consensus Group, comprising 79 specialists from 14 countries, was organized into 12 separate subcommittees, each led by a clinician with advanced expertise in tuberous sclerosis complex and the relevant medical subspecialty. Each subcommittee focused on a specific disease area with important clinical management implications and was charged with formulating key clinical questions to address within its focus area, reviewing relevant literature, evaluating the strength of data, and providing a recommendation accordingly. The updated consensus recommendations for clinical surveillance and management in tuberous sclerosis complex are summarized here. The recommendations are relevant to the entire lifespan of the patient, from infancy to adulthood, including both individuals where the diagnosis is newly made as well as individuals where the diagnosis already is established. The 2012 International Tuberous Sclerosis Complex Consensus Recommendations provide an evidence-based, standardized approach for optimal clinical care provided for individuals with tuberous sclerosis complex. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Understanding complex clinical reasoning in infectious diseases for improving clinical decision support design.

Science.gov (United States)

Islam, Roosan; Weir, Charlene R; Jones, Makoto; Del Fiol, Guilherme; Samore, Matthew H

2015-11-30

Clinical experts' cognitive mechanisms for managing complexity have implications for the design of future innovative healthcare systems. The purpose of the study is to examine the constituents of decision complexity and explore the cognitive strategies clinicians use to control and adapt to their information environment. We used Cognitive Task Analysis (CTA) methods to interview 10 Infectious Disease (ID) experts at the University of Utah and Salt Lake City Veterans Administration Medical Center. Participants were asked to recall a complex, critical and vivid antibiotic-prescribing incident using the Critical Decision Method (CDM), a type of Cognitive Task Analysis (CTA). Using the four iterations of the Critical Decision Method, questions were posed to fully explore the incident, focusing in depth on the clinical components underlying the complexity. Probes were included to assess cognitive and decision strategies used by participants. The following three themes emerged as the constituents of decision complexity experienced by the Infectious Diseases experts: 1) the overall clinical picture does not match the pattern, 2) a lack of comprehension of the situation and 3) dealing with social and emotional pressures such as fear and anxiety. All these factors contribute to decision complexity. These factors almost always occurred together, creating unexpected events and uncertainty in clinical reasoning. Five themes emerged in the analyses of how experts deal with the complexity. Expert clinicians frequently used 1) watchful waiting instead of over- prescribing antibiotics, engaged in 2) theory of mind to project and simulate other practitioners' perspectives, reduced very complex cases into simple 3) heuristics, employed 4) anticipatory thinking to plan and re-plan events and consulted with peers to share knowledge, solicit opinions and 5) seek help on patient cases. The cognitive strategies to deal with decision complexity found in this study have important

Kinetics and thermodynamics of the bioreduction of potassium tetrachloroaurate using inactivated oat and wheat tissues

International Nuclear Information System (INIS)

Parsons, J. G.; Armendariz, V.; Lopez, M. L.; Jose-Yacaman, M.; Gardea-Torresdey, J. L.

2010-01-01

The reduction kinetics of gold(III) to gold(0), the growth of gold nanoparticles with time, and the activation energy of the nanoparticle formation were investigated using oat and wheat biomasses at pH 4. Both the gold reduction and the nanoparticle growth were found to follow first-order kinetics with nanoscale size ranges in the growth period of 1-6 h of 4.54-19 nm for oat biomass and 8.0-51.8 nm for wheat biomass. The formation of gold(0) on oat and wheat biomasses was determined to occur at rates of 0.040 and 0.049 mM/min, respectively. The rate of nanoparticles growth was determined to be 0.0052 and 0.0035 nm/min for wheat and oat, respectively, whereas the activation energy for the reduction of gold(III) on oat and wheat biomasses was 4.8 ± 0.5 and 0.66 ± 0.07 kJ/mol, respectively. However, the activation energy for the growth of the produced nanoparticles was determined to be 12.0 ± 1.2 and 17.0 ± 1.7 kJ/mol for oat and wheat, respectively. The lower activation energy for the wheat indicates that the reduction process is much more favorable on the wheat biomass.

GRAIL Gravity Observations of the Transition from Complex Crater to Peak-Ring Basin on the Moon: Implications for Crustal Structure and Impact Basin Formation

Science.gov (United States)

Baker, David M. H.; Head, James W.; Phillips, Roger J.; Neumann, Gregory A.; Bierson, Carver J.; Smith, David E.; Zuber, Maria T.

2017-01-01

High-resolution gravity data from the Gravity Recovery and Interior Laboratory (GRAIL) mission provide the opportunity to analyze the detailed gravity and crustal structure of impact features in the morphological transition from complex craters to peak-ring basins on the Moon. We calculate average radial profiles for free-air anomalies and Bouguer anomalies for peak-ring basins, proto-basins, and the largest complex craters. Complex craters and proto-basins have free-air anomalies that are positively correlated with surface topography, unlike the prominent lunar mascons (positive free-air anomalies in areas of low elevation) associated with large basins. The Bouguer gravity anomaly profiles of complex craters are highly irregular, with central positive anomalies that are generally absent or not clearly tied to interior morphology. In contrast, gravity profiles for peak-ring basins (approx. 200 km to 580 km) are much more regular and are highly correlated with surface morphology. A central positive Bouguer anomaly is confined within the peak ring and a negative Bouguer anomaly annulus extends from the edge of the positive anomaly outward to about the rim crest. A number of degraded basins lacking interior peak rings have diameters and gravity patterns similar to those of well-preserved peak-ring basins. If these structures represent degraded peak-ring basins, the number of peak-ring basins on the Moon would increase by more than a factor of two to 34. The gravity anomalies within basins are interpreted to be due to uplift of the mantle confined within the peak ring and an annulus of thickened crust between the peak ring and rim crest. We hypothesize that mantle uplift is influenced by interaction between the transient cavity and the mantle. Further, mascon formation is generally disconnected from the number of basin rings formed and occurs over a wide range of basin sizes. These observations have important implications for models of basin and mascon formation on the

GRAIL gravity observations of the transition from complex crater to peak-ring basin on the Moon: Implications for crustal structure and impact basin formation

Science.gov (United States)

Baker, David M. H.; Head, James W.; Phillips, Roger J.; Neumann, Gregory A.; Bierson, Carver J.; Smith, David E.; Zuber, Maria T.

2017-08-01

High-resolution gravity data from the Gravity Recovery and Interior Laboratory (GRAIL) mission provide the opportunity to analyze the detailed gravity and crustal structure of impact features in the morphological transition from complex craters to peak-ring basins on the Moon. We calculate average radial profiles of free-air anomalies and Bouguer anomalies for peak-ring basins, protobasins, and the largest complex craters. Complex craters and protobasins have free-air anomalies that are positively correlated with surface topography, unlike the prominent lunar mascons (positive free-air anomalies in areas of low elevation) associated with large basins. The Bouguer gravity anomaly profiles of complex craters are highly irregular, with central positive anomalies that are generally absent or not clearly tied to interior morphology. In contrast, gravity profiles for peak-ring basins (∼200 km to 580 km) are much more regular and are highly correlated with surface morphology. A central positive Bouguer anomaly is confined within the peak ring and a negative Bouguer anomaly annulus extends from the edge of the positive anomaly outward to about the rim crest. A number of degraded basins lacking interior peak rings have diameters and gravity patterns similar to those of well-preserved peak-ring basins. If these structures represent degraded peak-ring basins, the number of peak-ring basins on the Moon would increase by more than a factor of two to 34. The gravity anomalies within basins are interpreted to be due to uplift of the mantle confined within the peak ring and an annulus of thickened crust between the peak ring and rim crest. We hypothesize that mantle uplift is influenced by interaction between the transient cavity and the mantle. Further, mascon formation is generally disconnected from the number of basin rings formed and occurs over a wide range of basin sizes. These observations have important implications for models of basin and mascon formation on the Moon

Principles of assembly reveal a periodic table of protein complexes.

Science.gov (United States)

Ahnert, Sebastian E; Marsh, Joseph A; Hernández, Helena; Robinson, Carol V; Teichmann, Sarah A

2015-12-11

Structural insights into protein complexes have had a broad impact on our understanding of biological function and evolution. In this work, we sought a comprehensive understanding of the general principles underlying quaternary structure organization in protein complexes. We first examined the fundamental steps by which protein complexes can assemble, using experimental and structure-based characterization of assembly pathways. Most assembly transitions can be classified into three basic types, which can then be used to exhaustively enumerate a large set of possible quaternary structure topologies. These topologies, which include the vast majority of observed protein complex structures, enable a natural organization of protein complexes into a periodic table. On the basis of this table, we can accurately predict the expected frequencies of quaternary structure topologies, including those not yet observed. These results have important implications for quaternary structure prediction, modeling, and engineering. Copyright © 2015, American Association for the Advancement of Science.

A Silica-Supported Monoalkylated Tungsten Dioxo Complex Catalyst for Olefin Metathesis

KAUST Repository

Maity, Niladri

2018-02-15

A well-defined silica-supported monoalkylated tungsten dioxo complex [(Si-O-)W(=O)(CH-Bu)] was prepared by treatment of highly dehydroxylated silica (SiO: silica treated at 700 °C under high vacuum) with an ionic precursor complex [NEt][W(=O)(CH-Bu)]. The identity of the resulting neutral monoalkylated tungsten dioxo surface complex was established by means of elemental microanalysis and spectroscopic studies (IR, solid-state NMR, Raman, and X-ray absorption spectroscopies). The supported tungsten complex was found to act as a precatalyst for the self-metathesis of 1-octene in a batch reactor. The mechanistic implications of this reaction are discussed with the support of DFT calculations highlighting the potential occurrence of thus-far unexplored mechanistic pathways.

A Silica-Supported Monoalkylated Tungsten Dioxo Complex Catalyst for Olefin Metathesis

KAUST Repository

Maity, Niladri; Barman, Samir; Minenkov, Yury; Ould-Chikh, Samy; Abou-Hamad, Edy; Ma, Tao; Qureshi, Ziyauddin; Cavallo, Luigi; D'Elia, Valerio; Gates, Bruce C.; Basset, Jean-Marie

2018-01-01

A well-defined silica-supported monoalkylated tungsten dioxo complex [(Si-O-)W(=O)(CH-Bu)] was prepared by treatment of highly dehydroxylated silica (SiO: silica treated at 700 °C under high vacuum) with an ionic precursor complex [NEt][W(=O)(CH-Bu)]. The identity of the resulting neutral monoalkylated tungsten dioxo surface complex was established by means of elemental microanalysis and spectroscopic studies (IR, solid-state NMR, Raman, and X-ray absorption spectroscopies). The supported tungsten complex was found to act as a precatalyst for the self-metathesis of 1-octene in a batch reactor. The mechanistic implications of this reaction are discussed with the support of DFT calculations highlighting the potential occurrence of thus-far unexplored mechanistic pathways.

Cornelia de Lange syndrome and molecular implications of the cohesin complex: Abstracts from the 7th biennial scientific and educational symposium 2016

Science.gov (United States)

Kline, Antonie D.; Krantz, Ian D.; Deardorff, Matthew A.; Shirahige, Katsuhiko; Dorsett, Dale; Gerton, Jennifer L.; Wu, Meng; Mehta, Devanshi; Mills, Jason A.; Carrico, Cheri S.; Noon, Sarah; Herrera, Pamela S.; Horsfield, Julia A.; Bettale, Chiara; Morgan, Jeremy; Huisman, Sylvia A.; Moss, Jo; McCleery, Joseph; Grados, Marco; Hansen, Blake D.; Srivastava, Siddharth; Taylor-Snell, Emily; Kerr, Lynne M.; Katz, Olivia; Calof, Anne L.; Musio, Antonio; Egense, Alena; Haaland, Richard E.

2017-01-01

Cornelia de Lange Syndrome (CdLS) is due to mutations in the genes for the structural and regulatory proteins that make up the cohesin complex, and is considered a cohesinopathy disorder or, more recently, a transcriptomopathy. New phenotypes have been recognized in this expanding field. There are multiple clinical issues facing individuals with all forms of CdLS, particularly in the neurodevelopmental system, but also gastrointestinal, cardiac, and musculoskeletal. Aspects of developmental and cell biology have found common endpoints in the biology of the cohesin complex, with improved understanding of the mechanisms, easier diagnostic tests, and the possibility of potential therapeutics, all major clinical implications for the individual with CdLS. The following abstracts are the presentations from the 7th Cornelia de Lange Syndrome Scientific and Educational Symposium, June 22–23, 2016, in Orlando, FL, in conjunction with the Cornelia de Lange Syndrome Foundation National Meeting. In addition to the scientific and clinical discussions, there were talks related to practical aspects of behavior including autism, transitions, communication, access to medical care, and databases. At the end of the symposium, a panel was held, which included several parents, affected individuals and genetic counselors, and discussed the greatest challenges in life and how this information can assist in guiding future research. The Research Committee of the CdLS Foundation organizes this meeting, reviews, and accepts abstracts, and subsequently disseminates the information to the families through members of the Clinical Advisory Board and publications. AMA CME credits were provided by Greater Baltimore Medical Center, Baltimore, MD. PMID:28190301

Cornelia de Lange syndrome and molecular implications of the cohesin complex: Abstracts from the 7th biennial scientific and educational symposium 2016.

Science.gov (United States)

Kline, Antonie D; Krantz, Ian D; Deardorff, Matthew A; Shirahige, Katsuhiko; Dorsett, Dale; Gerton, Jennifer L; Wu, Meng; Mehta, Devanshi; Mills, Jason A; Carrico, Cheri S; Noon, Sarah; Herrera, Pamela S; Horsfield, Julia A; Bettale, Chiara; Morgan, Jeremy; Huisman, Sylvia A; Moss, Jo; McCleery, Joseph; Grados, Marco; Hansen, Blake D; Srivastava, Siddharth; Taylor-Snell, Emily; Kerr, Lynne M; Katz, Olivia; Calof, Anne L; Musio, Antonio; Egense, Alena; Haaland, Richard E

2017-05-01

Cornelia de Lange Syndrome (CdLS) is due to mutations in the genes for the structural and regulatory proteins that make up the cohesin complex, and is considered a cohesinopathy disorder or, more recently, a transcriptomopathy. New phenotypes have been recognized in this expanding field. There are multiple clinical issues facing individuals with all forms of CdLS, particularly in the neurodevelopmental system, but also gastrointestinal, cardiac, and musculoskeletal. Aspects of developmental and cell biology have found common endpoints in the biology of the cohesin complex, with improved understanding of the mechanisms, easier diagnostic tests, and the possibility of potential therapeutics, all major clinical implications for the individual with CdLS. The following abstracts are the presentations from the 7th Cornelia de Lange Syndrome Scientific and Educational Symposium, June 22-23, 2016, in Orlando, FL, in conjunction with the Cornelia de Lange Syndrome Foundation National Meeting. In addition to the scientific and clinical discussions, there were talks related to practical aspects of behavior including autism, transitions, communication, access to medical care, and databases. At the end of the symposium, a panel was held, which included several parents, affected individuals and genetic counselors, and discussed the greatest challenges in life and how this information can assist in guiding future research. The Research Committee of the CdLS Foundation organizes this meeting, reviews, and accepts abstracts, and subsequently disseminates the information to the families through members of the Clinical Advisory Board and publications. AMA CME credits were provided by Greater Baltimore Medical Center, Baltimore, MD. © 2017 Wiley Periodicals, Inc.

Implicative Algebras

African Journals Online (AJOL)

Tadesse

In this paper we introduce the concept of implicative algebras which is an equivalent definition of lattice implication algebra of Xu (1993) and further we prove that it is a regular Autometrized. Algebra. Further we remark that the binary operation → on lattice implicative algebra can never be associative. Key words: Implicative ...

Implications of tristability in pattern-forming ecosystems

Science.gov (United States)

Zelnik, Yuval R.; Gandhi, Punit; Knobloch, Edgar; Meron, Ehud

2018-03-01

Many ecosystems show both self-organized spatial patterns and multistability of possible states. The combination of these two phenomena in different forms has a significant impact on the behavior of ecosystems in changing environments. One notable case is connected to tristability of two distinct uniform states together with patterned states, which has recently been found in model studies of dryland ecosystems. Using a simple model, we determine the extent of tristability in parameter space, explore its effects on the system dynamics, and consider its implications for state transitions or regime shifts. We analyze the bifurcation structure of model solutions that describe uniform states, periodic patterns, and hybrid states between the former two. We map out the parameter space where these states exist, and note how the different states interact with each other. We further focus on two special implications with ecological significance, breakdown of the snaking range and complex fronts. We find that the organization of the hybrid states within a homoclinic snaking structure breaks down as it meets a Maxwell point where simple fronts are stationary. We also discover a new series of complex fronts between the uniform states, each with its own velocity. We conclude with a brief discussion of the significance of these findings for the dynamics of regime shifts and their potential control.

Complexity of Some Language Fragments of Fuzzy Logics

Czech Academy of Sciences Publication Activity Database

Haniková, Zuzana

2017-01-01

Roč. 21, č. 1 (2017), s. 69-77 ISSN 1432-7643 R&D Projects: GA ČR GAP202/11/1632 Institutional support: RVO:67985807 Keywords : fuzzy logic * propositional logic * language fragment * implicational fragment * commutative semigroup * equational theory * computational complexity Subject RIV: BA - General Mathematics OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 2.472, year: 2016

DNA methylation signatures of chronic low-grade inflammation are associated with complex diseases

NARCIS (Netherlands)

S. Ligthart (Symen); Marzi, C. (Carola); Aslibekyan, S. (Stella); Mendelson, M.M. (Michael M.); K.N. Conneely (Karen N.); T. Tanaka (Toshiko); Colicino, E. (Elena); L. Waite (Lindsay); R. Joehanes (Roby); W. Guan (Weihua); J. Brody (Jennifer); C.E. Elks (Cathy); R.E. Marioni (Riccardo); M.A. Jhun (Min A.); Agha, G. (Golareh); J. Bressler (Jan); C.K. Ward-Caviness (Cavin K.); B.H. Chen (Brian); T. Huan (Tianxiao); K.M. Bakulski (Kelly M.); E. Salfati (Elias); Fiorito, G. (Giovanni); S. Wahl (Simone); K. Schramm (Katharina); Sha, J. (Jin); D.G. Hernandez (Dena); Just, A.C. (Allan C.); J.A. Smith (Jennifer A); N. Sotoodehnia (Nona); L.C. Pilling (Luke); J.S. Pankow (James); Tsao, P.S. (Phil S.); Liu, C. (Chunyu); W. Zhao (Wei); S. Guarrera (Simonetta); Michopoulos, V.J. (Vasiliki J.); Smith, A.K. (Alicia K.); M.J. Peters (Marjolein); D. Melzer (David); Vokonas, P. (Pantel); M. Fornage (Myriam); H. Prokisch (Holger); J.C. Bis (Joshua); A.Y. Chu (Audrey); C. Herder (Christian); H. Grallert (Harald); C. Yao (Chen); S. Shah (Sonia); A.F. McRae (Allan F.); H. Lin; S. Horvath (Steve); Fallin, D. (Daniele); A. Hofman (Albert); N.J. Wareham (Nick); K.L. Wiggins (Kerri); A.P. Feinberg (Andrew P.); J.M. Starr (John); P.M. Visscher (Peter); J. Murabito (Joanne); Kardia, S.L.R. (Sharon L.R.); D. Absher (Devin); E.B. Binder (Elisabeth); A. Singleton (Andrew); S. Bandinelli (Stefania); A. Peters (Annette); M. Waldenberger (Melanie); G. Matullo; Schwartz, J.D. (Joel D.); E.W. Demerath (Ellen); A.G. Uitterlinden (André); Meurs, J.B.J. (Joyce B.J.); O.H. Franco (Oscar); Y.D. Chen (Y.); D. Levy (Daniel); S.T. Turner (Stephen); I.J. Deary (Ian J.); K.J. Ressler (Kerry); J. Dupuis (Josée); L. Ferrucci (Luigi); Ong, K.K. (Ken K.); T.L. Assimes (Themistocles); E.A. Boerwinkle (Eric); W. Koenig (Wolfgang); D.K. Arnett (Donna); A.A. Baccarelli (Andrea A.); E.J. Benjamin (Emelia); A. Dehghan (Abbas)

2016-01-01

textabstractBackground: Chronic low-grade inflammation reflects a subclinical immune response implicated in the pathogenesis of complex diseases. Identifying genetic loci where DNA methylation is associated with chronic low-grade inflammation may reveal novel pathways or therapeutic targets for

Caspase cleaved presenilin-1 is part of active gamma-secretase complexes

DEFF Research Database (Denmark)

Hansson, Camilla A; Popescu, Bogdan O; Laudon, Hanna

2006-01-01

, and Abeta is believed to be central for the molecular pathogenesis of AD. Apoptosis has been implicated as one of the mechanisms behind the neuronal cell loss seen in AD. We have studied preservation and activity of the gamma-secretase complex during apoptosis in neuroblastoma cells (SH-SY5Y) exposed...

Interaction energies and structures of the (n 1–3) complexes

Indian Academy of Sciences (India)

JAMAL N DAWOUD

Lithium ion complexes; ab initio calculations; bond dissociation energy; electrostatic interaction; carbon oxide. 1. Introduction. The chemistry of alkali metal interactions with lig- ands has been the subject of considerable attention in the last twenty years. It has decisive implications in biology, chemistry and physics.1–3 The ...

Modeling Stochastic Complexity in Complex Adaptive Systems: Non-Kolmogorov Probability and the Process Algebra Approach.

Science.gov (United States)

Sulis, William H

2017-10-01

Walter Freeman III pioneered the application of nonlinear dynamical systems theories and methodologies in his work on mesoscopic brain dynamics.Sadly, mainstream psychology and psychiatry still cling to linear correlation based data analysis techniques, which threaten to subvert the process of experimentation and theory building. In order to progress, it is necessary to develop tools capable of managing the stochastic complexity of complex biopsychosocial systems, which includes multilevel feedback relationships, nonlinear interactions, chaotic dynamics and adaptability. In addition, however, these systems exhibit intrinsic randomness, non-Gaussian probability distributions, non-stationarity, contextuality, and non-Kolmogorov probabilities, as well as the absence of mean and/or variance and conditional probabilities. These properties and their implications for statistical analysis are discussed. An alternative approach, the Process Algebra approach, is described. It is a generative model, capable of generating non-Kolmogorov probabilities. It has proven useful in addressing fundamental problems in quantum mechanics and in the modeling of developing psychosocial systems.

Promoting evaluation capacity building in a complex adaptive system.

Science.gov (United States)

Lawrenz, Frances; Kollmann, Elizabeth Kunz; King, Jean A; Bequette, Marjorie; Pattison, Scott; Nelson, Amy Grack; Cohn, Sarah; Cardiel, Christopher L B; Iacovelli, Stephanie; Eliou, Gayra Ostgaard; Goss, Juli; Causey, Lauren; Sinkey, Anne; Beyer, Marta; Francisco, Melanie

2018-04-10

This study provides results from an NSF funded, four year, case study about evaluation capacity building in a complex adaptive system, the Nanoscale Informal Science Education Network (NISE Net). The results of the Complex Adaptive Systems as a Model for Network Evaluations (CASNET) project indicate that complex adaptive system concepts help to explain evaluation capacity building in a network. The NISE Network was found to be a complex learning system that was supportive of evaluation capacity building through feedback loops that provided for information sharing and interaction. Participants in the system had different levels of and sources of evaluation knowledge. To be successful at building capacity, the system needed to have a balance between both centralized and decentralized control, coherence, redundancy, and diversity. Embeddedness of individuals within the system also provided support and moved the capacity of the system forward. Finally, success depended on attention being paid to the control of resources. Implications of these findings are discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Napoleon Complex: When Shorter Men Take More.

Science.gov (United States)

Knapen, Jill E P; Blaker, Nancy M; Van Vugt, Mark

2018-05-01

Inspired by an evolutionary psychological perspective on the Napoleon complex, we hypothesized that shorter males are more likely to show indirect aggression in resource competitions with taller males. Three studies provide support for our interpretation of the Napoleon complex. Our pilot study shows that men (but not women) keep more resources for themselves when they feel small. When paired with a taller male opponent (Study 1), shorter men keep more resources to themselves in a game in which they have all the power (dictator game) versus a game in which the opponent also has some power (ultimatum game). Furthermore, shorter men are not more likely to show direct, physical aggression toward a taller opponent (Study 2). As predicted by the Napoleon complex, we conclude that (relatively) shorter men show greater behavioral flexibility in securing resources when presented with cues that they are physically less competitive. Theoretical and practical implications are discussed.

Effects of ionizing radiations on DNA-protein complexes; Effets des radiations ionisantes sur des complexes ADN-proteine

Energy Technology Data Exchange (ETDEWEB)

Gillard, N

2005-11-15

The radio-induced destruction of DNA-protein complexes may have serious consequences for systems implicated in important cellular functions. The first system which has been studied is the lactose operon system, that regulates gene expression in Escherichia coli. First of all, the repressor-operator complex is destroyed after irradiation of the complex or of the protein alone. The damaging of the domain of repressor binding to DNA (headpiece) has been demonstrated and studied from the point of view of peptide chain integrity, conformation and amino acids damages. Secondly, dysfunctions of the in vitro induction of an irradiated repressor-unirradiated DNA complex have been observed. These perturbations, due to a decrease of the number of inducer binding sites, are correlated to the damaging of tryptophan residues. Moreover, the inducer protects the repressor when they are irradiated together, both by acting as a scavenger in the bulk, and by the masking of its binding site on the protein. The second studied system is formed by Fpg (for Formamido pyrimidine glycosylase), a DNA repair protein and a DNA with an oxidative lesion. The results show that irradiation disturbs the repair both by decreasing its efficiency of DNA lesion recognition and binding, and by altering its enzymatic activity. (author)

Understanding the Complex Processes in Developing Student Teachers' Knowledge about Grammar

Science.gov (United States)

Svalberg, Agneta M.-L.

2015-01-01

This article takes the view that grammar is driven by user choices and is therefore complex and dynamic. This has implications for the teaching of grammar in language teacher education and how teachers' cognitions about grammar, and hence their own grammar teaching, might change. In this small, interpretative study, the participants--students on…

Change in composition of the Anopheles gambiae complex and its possible implications for the transmission of malaria and lymphatic filariasis in north-eastern Tanzania

Directory of Open Access Journals (Sweden)

Derua Yahya A

2012-06-01

decline has been most marked for An. gambiae s.s., and least for An. arabiensis, leading to current predominance of the latter. Due to differences in biology and vectorial capacity of the An. gambiae s.l. complex the change in sibling species composition will have important implications for the epidemiology and control of malaria and lymphatic filariasis in the study area.

Implication of Ccr4-Not complex function in mRNA quality control in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Assenholt, Jannie; Mouaikel, John; Saguez, Cyril

2011-01-01

RNPs are exported to the cytoplasm. The Ccr4-Not complex, which constitutes the major S. cerevisiae cytoplasmic deadenylase, has recently been implied in nuclear exosome–related processes. Consistent with a possible nuclear function of the complex, the deletion or mutation of Ccr4-Not factors also elicits...

Infrared spectroscopy and density functional calculations on titanium-dinitrogen complexes

Science.gov (United States)

Yoo, Hae-Wook; Choi, Changhyeok; Cho, Soo Gyeong; Jung, Yousung; Choi, Myong Yong

2018-04-01

Titanium-nitrogen complexes were generated by laser ablated titanium (Ti) atoms and N2 gas molecules in this study. These complexes were isolated on the pre-deposited solid Ar matrix on the pre-cooled KBr window (T ∼ 5.4 K), allowing infrared spectra to be measured. Laser ablation experiments with 15N2 isotope provided distinct isotopic shifts in the infrared spectra that strongly implicated the formation of titanium-nitrogen complexes, Ti(NN)x. Density functional theory (DFT) calculations were employed to investigate the molecular structures, electronic ground state, relative energies, and IR frequencies of the anticipated Ti(NN)x complexes. Based on laser ablation experiments and DFT calculations, we were able to assign multiple Ti(NN)x (x = 1-6) species. Particularly, Ti(NN)5 and Ti(NN)6, which have high nitrogen content, may serve as good precursors in preparing polynitrogens.

Relationships between structural complexity, coral traits, and reef fish assemblages

Science.gov (United States)

Darling, Emily S.; Graham, Nicholas A. J.; Januchowski-Hartley, Fraser A.; Nash, Kirsty L.; Pratchett, Morgan S.; Wilson, Shaun K.

2017-06-01

With the ongoing loss of coral cover and the associated flattening of reef architecture, understanding the links between coral habitat and reef fishes is of critical importance. Here, we investigate whether considering coral traits and functional diversity provides new insights into the relationship between structural complexity and reef fish communities, and whether coral traits and community composition can predict structural complexity. Across 157 sites in Seychelles, Maldives, the Chagos Archipelago, and Australia's Great Barrier Reef, we find that structural complexity and reef zone are the strongest and most consistent predictors of reef fish abundance, biomass, species richness, and trophic structure. However, coral traits, diversity, and life histories provided additional predictive power for models of reef fish assemblages, and were key drivers of structural complexity. Our findings highlight that reef complexity relies on living corals—with different traits and life histories—continuing to build carbonate skeletons, and that these nuanced relationships between coral assemblages and habitat complexity can affect the structure of reef fish assemblages. Seascape-level estimates of structural complexity are rapid and cost effective with important implications for the structure and function of fish assemblages, and should be incorporated into monitoring programs.

Analytical applications of resins containing amide and polyamine functional groups

International Nuclear Information System (INIS)

Orf, G.M.

1977-12-01

A dibutyl amide resin is used for the separation of uranium(VI), thorium(IV), and zirconium(IV) from each other and several other metal ions. Uranium(VI) and thorium(IV) are determined in the presence of large excesses of foreign metal ions and anions. A practical application of the amide resin is studied by determining uranium in low grade uranium ores. The amide resin is also used for the selective concentration of gold(III) from sea water

Analytical applications of resins containing amide and polyamine functional groups

Energy Technology Data Exchange (ETDEWEB)

Orf, Gene Michael [Iowa State Univ., Ames, IA (United States)

1977-12-01

A dibutyl amide resin is used for the separation of uranium(VI), thorium(IV), and zirconium(IV) from each other and several other metal ions. Uranium(VI) and thorium(IV) are determined in the presence of large excesses of foreign metal ions and anions. A practical application of the amide resin is studied by determining uranium in low grade uranium ores. The amide resin is also used for the selective concentration of gold(III) from sea water.

Sibutramine-associated psychotic symptoms and zolpidem-induced complex behaviours: implications for patient safety.

Science.gov (United States)

Wiglusz, Mariusz S; Cubała, Wiesław Jerzy; Nowak, Paweł; Jakuszkowiak-Wojten, Katarzyna; Landowski, Jerzy; Krysta, Krzysztof

2013-09-01

Sibutramine is a weight loss agent recently withdrawn from the European market due to cardiovascular risk concerns. It was used for long-term obesity treatment. Zolpidem is a short acting hypnotic agent commonly used in the treatment of insomnia. A number of case reports describing psychotic reaction to sibutramine were reported in the literature. We present a case of a 61-year-old Caucasian woman who developed two psychotic episodes related to sibutramine treatment. The second psychotic episode was complicated with complex behaviours after zolpidem use due to insomnia. Sibutramine and zolpidem discontinuation resulted in rapid resolution of psychotic symptoms. This case suggests a possibility of incidence of psychotic symptoms and complex behaviour disturbances in patients prescribed sibutramine or other monoaminergic reuptake inhibitors.

Our Galactic Neighbor Hosts Complex Organic Molecules

Science.gov (United States)

Hensley, Kerry

2018-03-01

For the first time, data from the Atacama Large Millimeter/submillimeter Array (ALMA) reveal the presence of methyl formate and dimethyl ether in a star-forming region outside our galaxy. This discovery has important implications for the formation and survival of complex organic compounds importantfor the formation of life in low-metallicity galaxies bothyoung and old.No Simple Picture of Complex Molecule FormationALMA, pictured here with the Magellanic Clouds above, has observed organic molecules in our Milky Way Galaxy and beyond. [ESO/C. Malin]Complex organic molecules (those with at least six atoms, one or more of which must be carbon) are the precursors to the building blocks of life. Knowing how and where complex organic molecules can form is a key part of understanding how life came to be on Earth and how it might arise elsewhere in the universe. From exoplanet atmospheres to interstellar space, complex organic molecules are ubiquitous in the Milky Way.In our galaxy, complex organic molecules are often found in the intense environments of hot cores clumps of dense molecular gas surrounding the sites of star formation. However, its not yet fully understood how the complex organic molecules found in hot cores come to be. One possibility is that the compounds condense onto cold dust grains long before the young stars begin heating their natal shrouds. Alternatively, they might assemble themselves from the hot, dense gas surrounding the blazing protostars.Composite infrared and optical image of the N 113 star-forming region in the LMC. The ALMA coverage is indicated by the gray line. Click to enlarge. [Sewio et al. 2018]Detecting Complexity, a Galaxy AwayUsing ALMA, a team of researchers led by Marta Sewio (NASA Goddard Space Flight Center) recently detected two complex organic molecules methyl formate and dimethyl ether for the first time in our neighboring galaxy, the Large Magellanic Cloud (LMC). Previous searches for organic molecules in the LMC detected

Youth Work Transitions: A Review with Implications for Counselling and Career Practice

Science.gov (United States)

Parada, Filomena; Young, Richard A.

2013-01-01

We critically review studies highlighting youth's work transitions and derive some implications for career and counselling theory and practice. We first discuss today's hypermodern world, specifically the meanings being conveyed by today's complex social realities and their impact on individuals' (work) lives. An overview of…

Towards a more explicit writing pedagogy: The complexity of teaching argumentative writing

Directory of Open Access Journals (Sweden)

Jacqui Dornbrack

2014-04-01

Full Text Available Advances in technology, changes in communication practices, and the imperatives of the workplace have led to the repositioning of the role of writing in the global context. This has implications for the teaching of writing in schools. This article focuses on the argumentative essay, which is a high-stakes genre. A sample of work from one Grade 10 student identified as high performing in a township school in Cape Town (South Africa is analysed. Drawing on the work of Ormerod and Ivanic, who argue that writing practices can be inferred from material artifacts, as well as critical discourse analysis, we show that the argumentative genre is complex, especially for novice first additional language English writers. This complexity is confounded by the conflation of the process and genre approaches in the Curriculum and Assessment Policy Statement (CAPS document. Based on the analysis we discuss the implications of planning, particularly in relation to thinking and reasoning, the need to read in order to write argument and how social and school capital are insufficient without explicit instruction of the conventions of this complex genre. These findings present some insights into particular input needed to improve writing pedagogy for specific genres.

The nonlinear effects of job complexity and autonomy on job satisfaction, turnover, and psychological well-being.

Science.gov (United States)

Chung-Yan, Greg A

2010-07-01

This study examines the interactive relationship between job complexity and job autonomy on job satisfaction, turnover intentions, and psychological well-being. It was hypothesized that the positive or motivating effects of job complexity are only realized when workers are given enough autonomy to effectively meet the challenges of complex jobs. Results show that not only do job complexity and job autonomy interact, but that the relationships to the outcome variables are curvilinear in form. Job complexity is shown to be both a motivator and a stressor when job autonomy is low. However, the most beneficial effects of job complexity occur when it is matched by a high level of job autonomy. Theoretical and practical implications are discussed.

Health Systems Research in a Complex and Rapidly Changing Context: Ethical Implications of Major Health Systems Change at Scale.

Science.gov (United States)

MacGregor, Hayley; Bloom, Gerald

2016-12-01

This paper discusses health policy and systems research in complex and rapidly changing contexts. It focuses on ethical issues at stake for researchers working with government policy makers to provide evidence to inform major health systems change at scale, particularly when the dynamic nature of the context and ongoing challenges to the health system can result in unpredictable outcomes. We focus on situations where 'country ownership' of HSR is relatively well established and where there is significant involvement of local researchers and close ties and relationships with policy makers are often present. We frame our discussion around two country case studies with which we are familiar, namely China and South Africa and discuss the implications for conducting 'embedded' research. We suggest that reflexivity is an important concept for health system researchers who need to think carefully about positionality and their normative stance and to use such reflection to ensure that they can negotiate to retain autonomy, whilst also contributing evidence for health system change. A research process informed by the notion of reflexive practice and iterative learning will require a longitudinal review at key points in the research timeline. Such review should include the convening of a deliberative process and should involve a range of stakeholders, including those most likely to be affected by the intended and unintended consequences of change. © 2016 The Authors Developing World Bioethics Published by John Wiley & Sons Ltd.

The complex and transdisciplinarity thought as frames of scientific research

Directory of Open Access Journals (Sweden)

Elvio Galati

2017-06-01

Full Text Available The work aims to describe and support, from the methodological point of view, Edgar Morin’s complex thought and Basarab Nicolescu’s transdisciplinarity. It is structured based on the philosophical and logical contexts of multi-method; and then developing methodological ideas from transdisciplinarity and complexity. The methodology used is the documentation, taking into account articles on doctrine and teaching experience. There is discourse analysis, classification and interpretation, also creating categories. The implications of integrative, complex and transdisciplinary philosophy are seen, in a research design for Social Sciences. Transdisciplinary category of "property" is provided, adding it to the "production" category. Developing the complexity and transdisciplinarity as a methodology, "transdisciplinary instructions" arise, which are applied to research although they were originally thought for teaching. From the structure of the research design, unsystematic transdisciplinary methodological strategies and systematic strategies element by element of the research project are identified. As another result, the creation of the category of "General Theory / Interim Science" is added, approached from transdisciplinarity

Structure of the Pds5-Scc1 Complex and Implications for Cohesin Function

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Kyle W. Muir

2016-03-01

Full Text Available Sister chromatid cohesion is a fundamental prerequisite to faithful genome segregation. Cohesion is precisely regulated by accessory factors that modulate the stability with which the cohesin complex embraces chromosomes. One of these factors, Pds5, engages cohesin through Scc1 and is both a facilitator of cohesion, and, conversely also mediates the release of cohesin from chromatin. We present here the crystal structure of a complex between budding yeast Pds5 and Scc1, thus elucidating the molecular basis of Pds5 function. Pds5 forms an elongated HEAT repeat that binds to Scc1 via a conserved surface patch. We demonstrate that the integrity of the Pds5-Scc1 interface is indispensable for the recruitment of Pds5 to cohesin, and that its abrogation results in loss of sister chromatid cohesion and cell viability.

Acaiaca Granulite Complex, MG: age, petrogenesis and tectonics implications

International Nuclear Information System (INIS)

Teixeira, W.; Kawashita, K.; Evangelista, H.J.; Taylor, P.N.

1987-01-01

Rb-SR and Pb-Pb geochronological work has been carried out on rocks from the Acaiaca granulite complex (mainly pyribolites, piriclasites and plagiogranulites) in Minas Gerais state. The results are interpreted together with petrographical and geochemical data, in order to delineate the evolution of those rocks. The Rb-Pb whole rock isochrons are concordant in age (around 2.0 b.y.) and they define the Transamazonian orogeny as the main event in the investigated area. In addition, the Sr and Pb evidences suggest a strong reworking of prior continental crust at that time. In turn, the estimation of P-T conditions of regional metamorphism based on geo thermo barometric calculations and on petrology resulted in T ≅ 700-900 O C and P tot =5,6-8 and 8-10 Kbar. The whole group of data is coherent with the development of is Transamazonian mobile zone of ensialic character, along the eastern border of an Archaean fragment. Within an area considered cratonic during the Upper Proterozoic. A model of evolution of the Sao Francisco Craton as well the differences between the Archaean and early Proterozoic domains are discussed. (M.V.M.)

The Impact of Complexity on Shaping Logistics Strategies in Global Supply Chains

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Agnieszka Szmelter

2017-04-01

Full Text Available Aim/purpose - The paper aims to summarize approaches to complexity management by implementing particular logistics concepts within logistics strategies in global supply chains and to highlight a research gap in this regard. Additionally, complexity management concepts are presented. Design/methodology/approach - To achieve the research objective, a systematic literature review was used. 11 research paper were analyzed with use of review protocol. Findings - Approaches to mentioned research problem are heterogeneous in current literature and there is a research gap in complexity studies in logistics, precluding further research, for example, on complexity measurement systems. Research implications/limitations - Identified research gap will require further studies. Studied area requires more empirical research, especially in the field of complexity measurement and management techniques in particular global supply chains. Originality/value/contribution - The paper summarizes current knowledge about logistics concepts helping to manage complexity in global supply chains and defines research gaps. There are no available literature summary of that kind. The article contains a full review of logistics complexity management concepts presented in scientific literature until the end of 2016.

Implementation of Complex Biological Logic Circuits Using Spatially Distributed Multicellular Consortia

Science.gov (United States)

Urrios, Arturo; de Nadal, Eulàlia; Solé, Ricard; Posas, Francesc

2016-01-01

Engineered synthetic biological devices have been designed to perform a variety of functions from sensing molecules and bioremediation to energy production and biomedicine. Notwithstanding, a major limitation of in vivo circuit implementation is the constraint associated to the use of standard methodologies for circuit design. Thus, future success of these devices depends on obtaining circuits with scalable complexity and reusable parts. Here we show how to build complex computational devices using multicellular consortia and space as key computational elements. This spatial modular design grants scalability since its general architecture is independent of the circuit’s complexity, minimizes wiring requirements and allows component reusability with minimal genetic engineering. The potential use of this approach is demonstrated by implementation of complex logical functions with up to six inputs, thus demonstrating the scalability and flexibility of this method. The potential implications of our results are outlined. PMID:26829588

EPR spectroscopy of complex biological iron-sulfur systems.

Science.gov (United States)

Hagen, Wilfred R

2018-02-21

From the very first discovery of biological iron-sulfur clusters with EPR, the spectroscopy has been used to study not only purified proteins but also complex systems such as respiratory complexes, membrane particles and, later, whole cells. In recent times, the emphasis of iron-sulfur biochemistry has moved from characterization of individual proteins to the systems biology of iron-sulfur biosynthesis, regulation, degradation, and implications for human health. Although this move would suggest a blossoming of System-EPR as a specific, non-invasive monitor of Fe/S (dys)homeostasis in whole cells, a review of the literature reveals limited success possibly due to technical difficulties in adherence to EPR spectroscopic and biochemical standards. In an attempt to boost application of System-EPR the required boundary conditions and their practical applications are explicitly and comprehensively formulated.

Synthesis of a Benzodiazepine-derived Rhodium NHC Complex by C-H Bond Activation

Energy Technology Data Exchange (ETDEWEB)

Bergman, Roberg G.; Gribble, Jr., Michael W.; Ellman, Jonathan A.

2008-01-30

The synthesis and characterization of a Rh(I)-NHC complex generated by C-H activation of 1,4-benzodiazepine heterocycle are reported. This complex constitutes a rare example of a carbene tautomer of a 1,4-benzodiazepine aldimine stabilized by transition metal coordination and demonstrates the ability of the catalytically relevant RhCl(PCy{sub 3}){sub 2} fragment to induce NHC-forming tautomerization of heterocycles possessing a single carbene-stabilizing heteroatom. Implications for the synthesis of benzodiazepines and related pharmacophores via C-H functionalization are discussed.

Geochemistry of Gneisses from Dabie Complex and Tongbai Complex in Qinling-Tongbai-Dabie Orogenic Belt: Implications for Location of Yangtze-Sino-Korean Suture

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

The Dabie complex (DC) and the Tongbai complex (TBC) are separately distributed in the middle and eastern parts of the Qinling-Tongbai-Dabie orogenic belt. In this study, the Dabie complex can be divided into two units: one is the complex with no high pressure and ultrahigh pressure metamorphic rocks (DC1), and the other is the complex containing coesite-bearing eclogite lenses or boudins (DC2). Gneisses are predominant in the TBC, DC1 and DC2. Major and trace element data of gneisses in the TBC, DC1 and DC2 show them to be the orthogneisses. The gneisses in the DC1 have higher incompatible element contents and higher ratios of w(K2O)/w(Na2O) and w(La)n/w(Yb)n than those in the DC2. However, no obvious differences arise in other element contents and the ratios of w(La)/w( Nb), w(Nb)/w(Th), w(Nb)/w(Hf), w(Ba)/w(La), w(Sm)/w(Nd) and w(Th)/w(U) between the gneisses in the DC2 and those in the DC1. These observations suggest that the protoliths of the gneisses in the DC2 have affinities to those in the DC1. The difference between the DC1 and DC2 gneisses in incompat- ible element contents could reflect the difference in their partial melting extent. The TBC gneisses are geochemically similar to the DC1 gneisses, suggesting that the TBC and DC1 gneisses are the same lithologic unit in the Qinling-Tongbai-Dabie orogenic belt and that they have experienced similar formations and evolution histories. In the Qinling-Tongbai area, the TBC is part of the northern blocks of the Yangtze craton. Given the similarity of geochemical characteristics, the rock assemblage and the ages between the TBC and DC1 gneisses, we can infer that the Dabie complex also belongs to the northern blocks of the Yangtze craton. In terms of the distribution of eciogites and metamorphic facies, we propose that the collisionai suture in the Dabie area is distributed along the Xiaotian-Mozitan fault, at the contact with the Shang-Dan-Tongbai fault to the west.

Complexity of intravenous iron nanoparticle formulations: implications for bioequivalence evaluation.

Science.gov (United States)

Pai, Amy Barton

2017-11-01

Intravenous iron formulations are a class of complex drugs that are commonly used to treat a wide variety of disease states associated with iron deficiency and anemia. Venofer® (iron-sucrose) is one of the most frequently used formulations, with more than 90% of dialysis patients in the United States receiving this formulation. Emerging data from global markets outside the United States, where many iron-sucrose similars or copies are available, have shown that these formulations may have safety and efficacy profiles that differ from the reference listed drug. This may be attributable to uncharacterized differences in physicochemical characteristics and/or differences in labile iron release. As bioequivalence evaluation guidance evolves, clinicians should be educated on these potential clinical issues before a switch to the generic formulation is made in the clinical setting. © 2017 New York Academy of Sciences.

Understanding implementation in complex public organizations – implication for practice

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Gry Cecilie Høiland

2016-10-01

Full Text Available The effective implementation of politically initiated public service innovations to the front-lines of the public service organization, where the innovation is to be applied, is a challenge that both practitioners and researchers struggle to solve. We highlight the importance of analysing contextual factors at several levels of the implementation system, as well as the importance of considering how the practical everyday work situations of the front-line workers influence their application of the innovation in question. We illustrate this by exploring the implementation process of a specific work inclusion measure, looking at its wider context and some of its implementation outcomes at a specific public agency. The intention is to illustrate the significance of considering the contextual complexity influencing implementation work as a reminder for practitioners to take this into account in their planning and practices.

Polyelectrolyte-modified cowpea mosaic virus for the synthesis of gold nanoparticles.

Science.gov (United States)

Aljabali, Alaa A A; Evans, David J

2014-01-01

Polyelectrolyte surface-modified cowpea mosaic virus (CPMV) can be used for the templated synthesis of narrowly dispersed gold nanoparticles. Cationic polyelectrolyte, poly(allylamine) hydrochloride, is electrostatically bound to the external surface of the virus capsid. The polyelectrolyte-coated CPMV promotes adsorption of aqueous gold hydroxide anionic species, prepared from gold(III) chloride and potassium carbonate, that are easily reduced to form CPMV-templated gold nanoparticles. The process is simple and environmentally benign using only water as solvent at ambient temperature.

Contribution of parenting to complex syntax development in preschool children with developmental delays or typical development.

Science.gov (United States)

Moody, C T; Baker, B L; Blacher, J

2018-05-10

Despite studies of how parent-child interactions relate to early child language development, few have examined the continued contribution of parenting to more complex language skills through the preschool years. The current study explored how positive and negative parenting behaviours relate to growth in complex syntax learning from child age 3 to age 4 years, for children with typical development or developmental delays (DDs). Participants were children with or without DD (N = 60) participating in a longitudinal study of development. Parent-child interactions were transcribed and coded for parenting domains and child language. Multiple regression analyses were used to identify the contribution of parenting to complex syntax growth in children with typical development or DD. Analyses supported a final model, F(9,50) = 11.90, P < .001, including a significant three-way interaction between positive parenting behaviours, negative parenting behaviours and child delay status. This model explained 68.16% of the variance in children's complex syntax at age 4. Simple two-way interactions indicated differing effects of parenting variables for children with or without DD. Results have implications for understanding of complex syntax acquisition in young children, as well as implications for interventions. © 2018 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

Genome-wide analyses of the Bemisia tabaci species complex reveal contrasting patterns of admixture and complex demographic histories.

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S Elfekih

Full Text Available Once considered a single species, the whitefly, Bemisia tabaci, is a complex of numerous morphologically indistinguishable species. Within the last three decades, two of its members (MED and MEAM1 have become some of the world's most damaging agricultural pests invading countries across Europe, Africa, Asia and the Americas and affecting a vast range of agriculturally important food and fiber crops through both feeding-related damage and the transmission of numerous plant viruses. For some time now, researchers have relied on a single mitochondrial gene and/or a handful of nuclear markers to study this species complex. Here, we move beyond this by using 38,041 genome-wide Single Nucleotide Polymorphisms, and show that the two invasive members of the complex are closely related species with signatures of introgression with a third species (IO. Gene flow patterns were traced between contemporary invasive populations within MED and MEAM1 species and these were best explained by recent international trade. These findings have profound implications for delineating the B. tabaci species status and will impact quarantine measures and future management strategies of this global pest.

COMPLEX HOST-PARASITE SYSTEMS IN MARTES: IMPLICATIONS FOR CONSERVATION BIOLOGY OF ENDEMIC FAUNAS.

Science.gov (United States)

Complex assemblages of hosts and parasites reveal insights about biogeography and ecology and inform us about processes which serve to structure faunal diversity and the biosphere in space and time. Exploring aspects of parasite diversity among martens (species of Martes) and other mustelids reveal...

A Mathematical Approach to Supply Complexity Management Efficiency Evaluation for Supply Chain

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Changhee Kim

2015-01-01

Full Text Available This study aims to identify the factors of complexity due to the globalization of supply chain and to measure the management efficiency of the factors which cause the supply complexity within supply chain. This study conducts an analysis to utilize linear programming and bootstrapping, targeting 12 Korean companies among the selected companies in Fortune Global 500. According to the results from the analysis, 4 companies with relatively high management efficiency of the factors which cause the supply complexity and 8 companies with relatively low management efficiency are found. The research findings reveal that public companies with the small number of products, factories, and providers relatively manage the supply complexity compared to private companies. Moreover, this study suggests projection point as a direction for relatively less efficient companies and excess quantity of input which should reduce for its achievement. This study also has an implication to establish a further standard of efficiency to manage the supply complexity for companies.

Architecture and ssDNA interaction of the Timeless-Tipin-RPA complex.

Science.gov (United States)

Witosch, Justine; Wolf, Eva; Mizuno, Naoko

2014-11-10

The Timeless-Tipin (Tim-Tipin) complex, also referred to as the fork protection complex, is involved in coordination of DNA replication. Tim-Tipin is suggested to be recruited to replication forks via Replication Protein A (RPA) but details of the interaction are unknown. Here, using cryo-EM and biochemical methods, we characterized complex formation of Tim-Tipin, RPA and single-stranded DNA (ssDNA). Tim-Tipin and RPA form a 258 kDa complex with a 1:1:1 stoichiometry. The cryo-EM 3D reconstruction revealed a globular architecture of the Tim-Tipin-RPA complex with a ring-like and a U-shaped domain covered by a RPA lid. Interestingly, RPA in the complex adopts a horse shoe-like shape resembling its conformation in the presence of long ssDNA (>30 nucleotides). Furthermore, the recruitment of the Tim-Tipin-RPA complex to ssDNA is modulated by the RPA conformation and requires RPA to be in the more compact 30 nt ssDNA binding mode. The dynamic formation and disruption of the Tim-Tipin-RPA-ssDNA complex implicates the RPA-based recruitment of Tim-Tipin to the replication fork. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Complexity, erotica and conflict in the urban public space

Directory of Open Access Journals (Sweden)

Enrique Díaz Álvarez

2011-09-01

Full Text Available This article highlights the importance of the urban public space, as the quintessential scenario of intercultural interaction and communication. From a context of globalisation, and from an ethical-political perspective, the author urges a reconsideration of the complexity, eroticism and conflicts that are characterised by coexistence in the city, as elements that are capable of directing dialogue, co-implication and construction of affinities between individuals who enjoy and champion the fact of being different.

Neuroprotective Effects and Mechanisms of Curcumin-Cu(II) and -Zn(II) Complexes Systems and Their Pharmacological Implications.

Science.gov (United States)

Yan, Fa-Shun; Sun, Jian-Long; Xie, Wen-Hai; Shen, Liang; Ji, Hong-Fang

2017-12-28

Alzheimer's disease (AD) is the main form of dementia and has a steadily increasing prevalence. As both oxidative stress and metal homeostasis are involved in the pathogenesis of AD, it would be interesting to develop a dual function agent, targeting the two factors. Curcumin, a natural compound isolated from the rhizome of Curcuma longa , is an antioxidant and can also chelate metal ions. Whether the complexes of curcumin with metal ions possess neuroprotective effects has not been evaluated. Therefore, the present study was designed to investigate the protective effects of the complexes of curcumin with Cu(II) or Zn(II) on hydrogen peroxide (H₂O₂)-induced injury and the underlying molecular mechanisms. The use of rat pheochromocytoma (PC12) cells, a widely used neuronal cell model system, was adopted. It was revealed that curcumin-Cu(II) complexes systems possessed enhanced O₂ ·- -scavenging activities compared to unchelated curcumin. In comparison with unchelated curcumin, the protective effects of curcumin-Cu(II) complexes systems were stronger than curcumin-Zn(II) system. Curcumin-Cu(II) or -Zn(II) complexes systems significantly enhanced the superoxide dismutase, catalase, and glutathione peroxidase activities and attenuated the increase of malondialdehyde levels and caspase-3 and caspase-9 activities, in a dose-dependent manner. The curcumin-Cu(II) complex system with a 2:1 ratio exhibited the most significant effect. Further mechanistic study demonstrated that curcumin-Cu(II) or -Zn(II) complexes systems inhibited cell apoptosis via downregulating the nuclear factor κB (NF-κB) pathway and upregulating Bcl-2/Bax pathway. In summary, the present study found that curcumin-Cu(II) or -Zn(II) complexes systems, especially the former, possess significant neuroprotective effects, which indicates the potential advantage of curcumin as a promising agent against AD and deserves further study.

Antecedents and Consequences of Consumer's Response to Health Information Complexity

DEFF Research Database (Denmark)

Hansen, Torben; Uth Thomsen, Thyra; Beckmann, Suzanne C.

2013-01-01

This study develops and empirically tests a model for understanding food consumers' health information seeking behaviour. Data were collected from 504 food consumers using a nationally representative consumer panel. The obtained Lisrel results suggest that consumers' product-specific health...... information seeking is positively affected by general food involvement and by usability of product-specific health information. Moreover, product-specific health information seeking and product-specific health information complexity are both positively related to post-purchase health-related dissonance....... This link between information complexity and post-purchase dissonance has implications for marketers of food products since our results suggest that consumers might avoid purchasing the same food item again if post-purchase dissonance is experienced....

Protein dynamics during presynaptic complex assembly on individual ssDNA molecules

Science.gov (United States)

Gibb, Bryan; Ye, Ling F.; Kwon, YoungHo; Niu, Hengyao; Sung, Patrick; Greene, Eric C.

2014-01-01

Homologous recombination is a conserved pathway for repairing double–stranded breaks, which are processed to yield single–stranded DNA overhangs that serve as platforms for presynaptic complex assembly. Here we use single–molecule imaging to reveal the interplay between Saccharomyce cerevisiae RPA, Rad52, and Rad51 during presynaptic complex assembly. We show that Rad52 binds RPA–ssDNA and suppresses RPA turnover, highlighting an unanticipated regulatory influence on protein dynamics. Rad51 binding extends the ssDNA, and Rad52–RPA clusters remain interspersed along the presynaptic complex. These clusters promote additional binding of RPA and Rad52. Together, our work illustrates the spatial and temporal progression of RPA and Rad52 association with the presynaptic complex, and reveals a novel RPA–Rad52–Rad51–ssDNA intermediate, which has implications for understanding how the activities of Rad52 and RPA are coordinated with Rad51 during the later stages recombination. PMID:25195049

Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

International Nuclear Information System (INIS)

Lee, Jiyoun

2012-01-01

We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry

Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

Energy Technology Data Exchange (ETDEWEB)

Lee, Jiyoun [Sungshin Women' s Univ., Seoul (Korea, Republic of)

2012-04-15

We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry.

Effects of ionizing radiations on DNA-protein complexes

International Nuclear Information System (INIS)

Gillard, N.

2005-11-01

The radio-induced destruction of DNA-protein complexes may have serious consequences for systems implicated in important cellular functions. The first system which has been studied is the lactose operon system, that regulates gene expression in Escherichia coli. First of all, the repressor-operator complex is destroyed after irradiation of the complex or of the protein alone. The damaging of the domain of repressor binding to DNA (headpiece) has been demonstrated and studied from the point of view of peptide chain integrity, conformation and amino acids damages. Secondly, dysfunctions of the in vitro induction of an irradiated repressor-unirradiated DNA complex have been observed. These perturbations, due to a decrease of the number of inducer binding sites, are correlated to the damaging of tryptophan residues. Moreover, the inducer protects the repressor when they are irradiated together, both by acting as a scavenger in the bulk, and by the masking of its binding site on the protein. The second studied system is formed by Fpg (for Formamido pyrimidine glycosylase), a DNA repair protein and a DNA with an oxidative lesion. The results show that irradiation disturbs the repair both by decreasing its efficiency of DNA lesion recognition and binding, and by altering its enzymatic activity. (author)

Global megatrends and their implications for environmental assessment practice

Energy Technology Data Exchange (ETDEWEB)

Retief, Francois, E-mail: francois.retief@nwu.ac.za [Research Unit for Environmental Sciences and Management, North-West University (South Africa); Bond, Alan [School of Environmental Sciences, University of East Anglia (United Kingdom); Research Unit for Environmental Sciences and Management, North-West University (South Africa); Pope, Jenny [Integral Sustainability (Australia); Research Unit for Environmental Sciences and Management, North-West University (South Africa); Morrison-Saunders, Angus [Murdoch University (Australia); Research Unit for Environmental, Sciences and Management, North-West University (South Africa); King, Nicholas [Research Unit for Environmental Sciences and Management, North-West University (South Africa)

2016-11-15

This paper addresses the future of environmental assessment (EA) practice in light of a rapidly changing world. We apply a literature review-based methodology to firstly identify key global megatrends and then reflect upon the implications for EA practice based on some known challenges. The key megatrends identified are synthesised into six categories: i) demographics, ii) urbanization, iii) technological innovation, iv) power shifts, v) resource scarcity and vi) climate change. We then discuss the implications of these megatrends for EA practice against four known EA challenges namely: dealing with i) complexity and uncertainty, ii) efficiency, iii) significance and iv) communication and participation. Our analysis suggests important implications for EA practice such as: increased difficulties with accuracy of prediction; the need for facilitative adaptation; an increase in the occurrence of unexpected events; higher expectations for procedural efficiency; challenges with information and communication management; dealing with significance judgements; and mitigation amidst resource scarcity and increasing pressures on earth systems. The megatrends underscore the need for continued evolution of EA thinking and practice, especially moving away from seeking a predictable single future or outcome towards the possibility of multiple scenarios with associated adaptability and enhanced system resilience capable of responding to rapid change.

Global megatrends and their implications for environmental assessment practice

International Nuclear Information System (INIS)

Retief, Francois; Bond, Alan; Pope, Jenny; Morrison-Saunders, Angus; King, Nicholas

2016-01-01

This paper addresses the future of environmental assessment (EA) practice in light of a rapidly changing world. We apply a literature review-based methodology to firstly identify key global megatrends and then reflect upon the implications for EA practice based on some known challenges. The key megatrends identified are synthesised into six categories: i) demographics, ii) urbanization, iii) technological innovation, iv) power shifts, v) resource scarcity and vi) climate change. We then discuss the implications of these megatrends for EA practice against four known EA challenges namely: dealing with i) complexity and uncertainty, ii) efficiency, iii) significance and iv) communication and participation. Our analysis suggests important implications for EA practice such as: increased difficulties with accuracy of prediction; the need for facilitative adaptation; an increase in the occurrence of unexpected events; higher expectations for procedural efficiency; challenges with information and communication management; dealing with significance judgements; and mitigation amidst resource scarcity and increasing pressures on earth systems. The megatrends underscore the need for continued evolution of EA thinking and practice, especially moving away from seeking a predictable single future or outcome towards the possibility of multiple scenarios with associated adaptability and enhanced system resilience capable of responding to rapid change.

Membrane Trafficking of Death Receptors: Implications on Signalling

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Wulf Schneider-Brachert

2013-07-01

Full Text Available Death receptors were initially recognised as potent inducers of apoptotic cell death and soon ambitious attempts were made to exploit selective ignition of controlled cellular suicide as therapeutic strategy in malignant diseases. However, the complexity of death receptor signalling has increased substantially during recent years. Beyond activation of the apoptotic cascade, involvement in a variety of cellular processes including inflammation, proliferation and immune response was recognised. Mechanistically, these findings raised the question how multipurpose receptors can ensure selective activation of a particular pathway. A growing body of evidence points to an elegant spatiotemporal regulation of composition and assembly of the receptor-associated signalling complex. Upon ligand binding, receptor recruitment in specialized membrane compartments, formation of receptor-ligand clusters and internalisation processes constitute key regulatory elements. In this review, we will summarise the current concepts of death receptor trafficking and its implications on receptor-associated signalling events.

Structural analysis and thermal remote sensing of the Los Humeros Volcanic Complex: Implications for volcano structure and geothermal exploration

Science.gov (United States)

Norini, G.; Groppelli, G.; Sulpizio, R.; Carrasco-Núñez, G.; Dávila-Harris, P.; Pellicioli, C.; Zucca, F.; De Franco, R.

2015-08-01

The Los Humeros Volcanic Complex (LHVC) is an important geothermal target in the Trans-Mexican Volcanic Belt. Understanding the structure of the LHVC and its influence on the occurrence of thermal anomalies and hydrothermal fluids is important to get insights into the interplay between the volcano-tectonic setting and the characteristics of the geothermal resources in the area. In this study, we present a structural analysis of the LHVC, focused on Quaternary tectonic and volcano-tectonic features, including the areal distribution of monogenetic volcanic centers. Morphostructural analysis and structural field mapping revealed the geometry, kinematics and dynamics of the structural features in the study area. Also, thermal infrared remote sensing analysis has been applied to the LHVC for the first time, to map the main endogenous thermal anomalies. These data are integrated with newly proposed Unconformity Bounded Stratigraphic Units, to evaluate the implications for the structural behavior of the caldera complex and geothermal field. The LHVC is characterized by a multistage formation, with at least two major episodes of caldera collapse: Los Humeros Caldera (460 ka) and Los Potreros Caldera (100 ka). The study suggests that the geometry of the first collapse recalls a trap-door structure and impinges on a thick volcanic succession (10.5-1.55 Ma), now hosting the geothermal reservoir. The main ring-faults of the two calderas are buried and sealed by the widespread post-calderas volcanic products, and for this reason they probably do not have enough permeability to be the main conveyers of the hydrothermal fluid circulation. An active, previously unrecognized fault system of volcano-tectonic origin has been identified inside the Los Potreros Caldera. This fault system is the main geothermal target, probably originated by active resurgence of the caldera floor. The active fault system defines three distinct structural sectors in the caldera floor, where the

Are Model Transferability And Complexity Antithetical? Insights From Validation of a Variable-Complexity Empirical Snow Model in Space and Time

Science.gov (United States)

Lute, A. C.; Luce, Charles H.

2017-11-01

The related challenges of predictions in ungauged basins and predictions in ungauged climates point to the need to develop environmental models that are transferable across both space and time. Hydrologic modeling has historically focused on modelling one or only a few basins using highly parameterized conceptual or physically based models. However, model parameters and structures have been shown to change significantly when calibrated to new basins or time periods, suggesting that model complexity and model transferability may be antithetical. Empirical space-for-time models provide a framework within which to assess model transferability and any tradeoff with model complexity. Using 497 SNOTEL sites in the western U.S., we develop space-for-time models of April 1 SWE and Snow Residence Time based on mean winter temperature and cumulative winter precipitation. The transferability of the models to new conditions (in both space and time) is assessed using non-random cross-validation tests with consideration of the influence of model complexity on transferability. As others have noted, the algorithmic empirical models transfer best when minimal extrapolation in input variables is required. Temporal split-sample validations use pseudoreplicated samples, resulting in the selection of overly complex models, which has implications for the design of hydrologic model validation tests. Finally, we show that low to moderate complexity models transfer most successfully to new conditions in space and time, providing empirical confirmation of the parsimony principal.

Fisher's Zeros as the Boundary of Renormalization Group Flows in Complex Coupling Spaces

International Nuclear Information System (INIS)

Denbleyker, A.; Du Daping; Liu Yuzhi; Meurice, Y.; Zou Haiyuan

2010-01-01

We propose new methods to extend the renormalization group transformation to complex coupling spaces. We argue that Fisher's zeros are located at the boundary of the complex basin of attraction of infrared fixed points. We support this picture with numerical calculations at finite volume for two-dimensional O(N) models in the large-N limit and the hierarchical Ising model. We present numerical evidence that, as the volume increases, the Fisher's zeros of four-dimensional pure gauge SU(2) lattice gauge theory with a Wilson action stabilize at a distance larger than 0.15 from the real axis in the complex β=4/g 2 plane. We discuss the implications for proofs of confinement and searches for nontrivial infrared fixed points in models beyond the standard model.

The status of the Lutzomyia longipalpis species complex and possible implications for Leishmania transmission

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Uribe Sandra

1999-01-01

Full Text Available The sand fly Lutzomyia longipalpis sensu latu has been identified as the principal vector of American visceral leishmaniasis, a potentially fatal disease that primarily affects children in several countries of South and Central America. Over the past several years increases have occurred both in the number of reported cases and the population at risk: approximately 1.6 million people reside in highly endemic areas with 16,000 cases reported annually. Several studies have attempted to relate the epidemiology of this disease to variability in Lu. longipalpis that is now recognized to be a complex of at least three sibling species. Morphological variation in this species was first noted by Mangabeira (1969. Since then physiological and biochemical differences have been reported by several investigators. Recent reports in Costa Rica of the presence of Lu. longipalpis in a focus of cutaneous leishmaniasis caused by Leishmania chagasi may be an additional indication of variability in this species. While existing evidence indicates that the morphospecies Lu. longipalpis may represent a complex of sibling species, genetic, epidemiological and ecological distinctions have not been fully resolved. Thus, delimitation of systematic boundaries within the complex and corresponding to geographic distributions and roles in transmission remain unresolved. The purpose of this review is to summarize from the literature observations of polymorphism in this morphospecies and consider what significance this reported variability may have to the epidemiology of visceral leishmaniasis.

An introduction to complex systems society, ecology, and nonlinear dynamics

CERN Document Server

Fieguth, Paul

2017-01-01

This undergraduate text explores a variety of large-scale phenomena - global warming, ice ages, water, poverty - and uses these case studies as a motivation to explore nonlinear dynamics, power-law statistics, and complex systems. Although the detailed mathematical descriptions of these topics can be challenging, the consequences of a system being nonlinear, power-law, or complex are in fact quite accessible. This book blends a tutorial approach to the mathematical aspects of complex systems together with a complementary narrative on the global/ecological/societal implications of such systems. Nearly all engineering undergraduate courses focus on mathematics and systems which are small scale, linear, and Gaussian. Unfortunately there is not a single large-scale ecological or social phenomenon that is scalar, linear, and Gaussian. This book offers students insights to better understand the large-scale problems facing the world and to realize that these cannot be solved by a single, narrow academic field or per...

The impact of economic complexity on carbon emissions: evidence from France.

Science.gov (United States)

Can, Muhlis; Gozgor, Giray

2017-07-01

This paper reanalyzes the determinants of the CO 2 emissions in France. For this purpose, it considers the unit root test with two structural breaks and a dynamic ordinary least squares estimation. The paper also considers the effects of the energy consumption and the economic complexity on CO 2 emissions. First, it is observed that the EKC hypothesis is valid in France. Second, the positive effect of the energy consumption on CO 2 emissions is obtained. Third, it is observed that a higher economic complexity suppresses the level of CO 2 emissions in the long run. The findings imply noteworthy environmental policy implications to decrease the level of CO 2 emissions in France.

A zinc complex of heparan sulfate destabilises lysozyme and alters its conformation

International Nuclear Information System (INIS)

Hughes, Ashley J.; Hussain, Rohanah; Cosentino, Cesare; Guerrini, Marco; Siligardi, Giuliano; Yates, Edwin A.; Rudd, Timothy R.

2012-01-01

Highlights: ► Zinc–heparan sulfate complex destabilises lysozyme, a model amyloid protein. ► Addition of zinc, without heparan sulfate, stabilises lysozyme. ► Heparan sulfate cation complexes provide alternative protein folding routes. -- Abstract: The naturally occurring anionic cell surface polysaccharide heparan sulfate is involved in key biological activities and is implicated in amyloid formation. Following addition of Zn–heparan sulfate, hen lysozyme, a model amyloid forming protein, resembled β-rich amyloid by far UV circular dichroism (increased β-sheet: +25%), with a significantly reduced melting temperature (from 68 to 58 °C) by fluorescence shift assay. Secondary structure stability of the Zn–heparan sulfate complex with lysozyme was also distinct from that with heparan sulfate, under stronger denaturation conditions using synchrotron radiation circular dichroism. Changing the cation associated with heparan sulfate is sufficient to alter the conformation and stability of complexes formed between heparan sulfate and lysozyme, substantially reducing the stability of the protein. Complexes of heparan sulfate and cations, such as Zn, which are abundant in the brain, may provide alternative folding routes for proteins.

Modelling hemoglobin and hemoglobin:haptoglobin complex clearance in a non-rodent species– pharmacokinetic and therapeutic implications

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Felicitas S Boretti

2014-10-01

Full Text Available Preclinical studies suggest that haptoglobin (Hp supplementation could be an effective therapeutic modality during acute or chronic hemolytic diseases. Hp prevents Hb extravasation and neutralizes Hb’s oxidative and NO scavenging activity in the vasculature. Small animal models such as mouse, rat and guinea pig appear to be valuable to provide proof-of-concept for Hb neutralization by Hp in diverse pre-clinical conditions. However, these species differ significantly from human in the clearance of Hb:Hp complexes, which leads to long persistence of circulating Hb:Hp complexes after administration of human plasma derived Hp. Alternative animal models must therefore be explored to guide pre-clinical development of these potential therapeutics. In contrast to rodents, dogs have high Hp plasma concentrations comparable to human. In this study we show that like human macrophages, dog peripheral blood monocyte derived macrophages express a glucocorticoid inducible endocytic clearance pathways with a high specificity for the Hb:Hp complex. Evaluating the Beagle dog as a non-rodent model species we provide the first pharmacokinetic parameter estimates of free Hb and Hb:Hp phenotype complexes. The data reflect a drastically reduced volume of distribution (Vc of the complex compared to free Hb, increased exposures (Cmax and AUC and significantly reduced total body clearance (CL with a terminal half-life (t1/2 of approximately 12 hours. Distribution and clearance was identical for dog and human Hb (± glucocorticoid stimulation and for dimeric and multimeric Hp preparations bound to Hb. Collectively, our study supports the dog as a non-rodent animal model to study pharmacological and pharmacokinetic aspects of Hb clearance systems and apply the model to studying Hp therapeutics.

The dynamic relationship between cerebellar Purkinje cell simple spikes and the spikelet number of complex spikes.

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Burroughs, Amelia; Wise, Andrew K; Xiao, Jianqiang; Houghton, Conor; Tang, Tianyu; Suh, Colleen Y; Lang, Eric J; Apps, Richard; Cerminara, Nadia L

2017-01-01

Purkinje cells are the sole output of the cerebellar cortex and fire two distinct types of action potential: simple spikes and complex spikes. Previous studies have mainly considered complex spikes as unitary events, even though the waveform is composed of varying numbers of spikelets. The extent to which differences in spikelet number affect simple spike activity (and vice versa) remains unclear. We found that complex spikes with greater numbers of spikelets are preceded by higher simple spike firing rates but, following the complex spike, simple spikes are reduced in a manner that is graded with spikelet number. This dynamic interaction has important implications for cerebellar information processing, and suggests that complex spike spikelet number may maintain Purkinje cells within their operational range. Purkinje cells are central to cerebellar function because they form the sole output of the cerebellar cortex. They exhibit two distinct types of action potential: simple spikes and complex spikes. It is widely accepted that interaction between these two types of impulse is central to cerebellar cortical information processing. Previous investigations of the interactions between simple spikes and complex spikes have mainly considered complex spikes as unitary events. However, complex spikes are composed of an initial large spike followed by a number of secondary components, termed spikelets. The number of spikelets within individual complex spikes is highly variable and the extent to which differences in complex spike spikelet number affects simple spike activity (and vice versa) remains poorly understood. In anaesthetized adult rats, we have found that Purkinje cells recorded from the posterior lobe vermis and hemisphere have high simple spike firing frequencies that precede complex spikes with greater numbers of spikelets. This finding was also evident in a small sample of Purkinje cells recorded from the posterior lobe hemisphere in awake cats. In addition

The Sleep Elaboration-Awake Pruning (SEAP) theory of memory: long term memories grow in complexity during sleep and undergo selection while awake. Clinical, psychopharmacological and creative implications.

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Charlton, Bruce G; Andras, Peter

2009-07-01

Long term memory (LTM) systems need to be adaptive such that they enhance an organism's reproductive fitness and self-reproducing in order to maintain their complexity of communications over time in the face of entropic loss of information. Traditional 'representation-consolidation' accounts conceptualize memory adaptiveness as due to memories being 'representations' of the environment, and the longevity of memories as due to 'consolidation' processes. The assumption is that memory representations are formed while an animal is awake and interacting with the environment, and these memories are consolidated mainly while the animal is asleep. So the traditional view of memory is 'instructionist' and assumes that information is transferred from the environment into the brain. By contrast, we see memories as arising endogenously within the brain's LTM system mainly during sleep, to create complex but probably maladaptive memories which are then simplified ('pruned') and selected during the awake period. When awake the LTM system is brought into a more intense interaction with past and present experience. Ours is therefore a 'selectionist' account of memory, and could be termed the Sleep Elaboration-Awake Pruning (or SEAP) theory. The SEAP theory explains the longevity of memories in the face of entropy by the tendency for memories to grow in complexity during sleep; and explains the adaptiveness of memory by selection for consistency with perceptions and previous memories during the awake state. Sleep is therefore that behavioural state during which most of the internal processing of the system of LTM occurs; and the reason sleep remains poorly understood is that its primary activity is the expansion of long term memories. By re-conceptualizing the relationship between memory, sleep and the environment; SEAP provides a radically new framework for memory research, with implications for the measurement of memory and the design of empirical investigations in clinical

Evolution and the complexity of bacteriophages

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Serwer Philip

2007-03-01

select for the presence of cellular gene homologs, (3 determine which, if any, bacteriophage genes were selected for maintaining the homologs and (4 determine the dynamics of homolog evolution. Implications of the hypothesis This hypothesis is an explanation of evolutionary leaps in general. If accurate, it will assist both understanding and influencing the evolution of microbes and their communities. Analysis of evolutionary complexity increase for at least prokaryotes should include analysis of genomes of long-genome bacteriophages.

Can complexity science inform physician leadership development?

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Grady, Colleen Marie

2016-07-04

Purpose The purpose of this paper is to describe research that examined physician leadership development using complexity science principles. Design/methodology/approach Intensive interviewing of 21 participants and document review provided data regarding physician leadership development in health-care organizations using five principles of complexity science (connectivity, interdependence, feedback, exploration-of-the-space-of-possibilities and co-evolution), which were grouped in three areas of inquiry (relationships between agents, patterns of behaviour and enabling functions). Findings Physician leaders are viewed as critical in the transformation of healthcare and in improving patient outcomes, and yet significant challenges exist that limit their development. Leadership in health care continues to be associated with traditional, linear models, which are incongruent with the behaviour of a complex system, such as health care. Physician leadership development remains a low priority for most health-care organizations, although physicians admit to being limited in their capacity to lead. This research was based on five principles of complexity science and used grounded theory methodology to understand how the behaviours of a complex system can provide data regarding leadership development for physicians. The study demonstrated that there is a strong association between physician leadership and patient outcomes and that organizations play a primary role in supporting the development of physician leaders. Findings indicate that a physician's relationship with their patient and their capacity for innovation can be extended as catalytic behaviours in a complex system. The findings also identified limiting factors that impact physicians who choose to lead, such as reimbursement models that do not place value on leadership and medical education that provides minimal opportunity for leadership skill development. Practical Implications This research provides practical

Neuroprotective Effects and Mechanisms of Curcumin–Cu(II and –Zn(II Complexes Systems and Their Pharmacological Implications

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Fa-Shun Yan

2017-12-01

Full Text Available Alzheimer’s disease (AD is the main form of dementia and has a steadily increasing prevalence. As both oxidative stress and metal homeostasis are involved in the pathogenesis of AD, it would be interesting to develop a dual function agent, targeting the two factors. Curcumin, a natural compound isolated from the rhizome of Curcuma longa, is an antioxidant and can also chelate metal ions. Whether the complexes of curcumin with metal ions possess neuroprotective effects has not been evaluated. Therefore, the present study was designed to investigate the protective effects of the complexes of curcumin with Cu(II or Zn(II on hydrogen peroxide (H2O2-induced injury and the underlying molecular mechanisms. The use of rat pheochromocytoma (PC12 cells, a widely used neuronal cell model system, was adopted. It was revealed that curcumin–Cu(II complexes systems possessed enhanced O2·–-scavenging activities compared to unchelated curcumin. In comparison with unchelated curcumin, the protective effects of curcumin–Cu(II complexes systems were stronger than curcumin–Zn(II system. Curcumin–Cu(II or –Zn(II complexes systems significantly enhanced the superoxide dismutase, catalase, and glutathione peroxidase activities and attenuated the increase of malondialdehyde levels and caspase-3 and caspase-9 activities, in a dose-dependent manner. The curcumin–Cu(II complex system with a 2:1 ratio exhibited the most significant effect. Further mechanistic study demonstrated that curcumin–Cu(II or –Zn(II complexes systems inhibited cell apoptosis via downregulating the nuclear factor κB (NF-κB pathway and upregulating Bcl-2/Bax pathway. In summary, the present study found that curcumin–Cu(II or –Zn(II complexes systems, especially the former, possess significant neuroprotective effects, which indicates the potential advantage of curcumin as a promising agent against AD and deserves further study.

Theoretical Investigations on the Mechanistic Aspects of O2 Activation by a Biomimetic Dinitrosyl Iron Complex

NARCIS (Netherlands)

Banerjee, Ambar; Sen, Souloke; Paul, Ankan

2018-01-01

Though dinitrosyl-iron complexes (DNICs) are largely believed to act as NO carriers, several experiments on model DNICs have suggested that they can also act as nitrating agents in presence of dioxygen. Oxygen activation by DNICs has been implicated as a possible route for protein tyrosine nitration

Hyperspectral forest monitoring and imaging implications

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Goodenough, David G.; Bannon, David

2014-05-01

The forest biome is vital to the health of the earth. Canada and the United States have a combined forest area of 4.68 Mkm2. The monitoring of these forest resources has become increasingly complex. Hyperspectral remote sensing can provide a wealth of improved information products to land managers to make more informed decisions. Research in this area has demonstrated that hyperspectral remote sensing can be used to create more accurate products for forest inventory (major forest species), forest health, foliar biochemistry, biomass, and aboveground carbon. Operationally there is a requirement for a mix of airborne and satellite approaches. This paper surveys some methods and results in hyperspectral sensing of forests and discusses the implications for space initiatives with hyperspectral sensing

Solution structures of lipoyl domains of the 2-oxo acid dehydrogenase complexes from Azotobacter vinelandii : implications for molecular recognition

NARCIS (Netherlands)

Berg, A.

1997-01-01

The 2-oxo acid dehydrogenase complexes are large multienzyme complexes that catalyse the irreversible oxidative decarboxylation of a specific 2-oxo acid to the corresponding acyl-CoA derivative. The pyruvate dehydrogenase complex (PDHC) converts the product of the glycolysis, pyruvate, to

Resolving complex chromosome structures during meiosis: versatile deployment of Smc5/6.

Science.gov (United States)

Verver, Dideke E; Hwang, Grace H; Jordan, Philip W; Hamer, Geert

2016-03-01

The Smc5/6 complex, along with cohesin and condensin, is a member of the structural maintenance of chromosome (SMC) family, large ring-like protein complexes that are essential for chromatin structure and function. Thanks to numerous studies of the mitotic cell cycle, Smc5/6 has been implicated to have roles in homologous recombination, restart of stalled replication forks, maintenance of ribosomal DNA (rDNA) and heterochromatin, telomerase-independent telomere elongation, and regulation of chromosome topology. The nature of these functions implies that the Smc5/6 complex also contributes to the profound chromatin changes, including meiotic recombination, that characterize meiosis. Only recently, studies in diverse model organisms have focused on the potential meiotic roles of the Smc5/6 complex. Indeed, Smc5/6 appears to be essential for meiotic recombination. However, due to both the complexity of the process of meiosis and the versatility of the Smc5/6 complex, many additional meiotic functions have been described. In this review, we provide a clear overview of the multiple functions found so far for the Smc5/6 complex in meiosis. Additionally, we compare these meiotic functions with the known mitotic functions in an attempt to find a common denominator and thereby create clarity in the field of Smc5/6 research.

VGKC complex antibodies in epilepsy: diagnostic yield and therapeutic implications.

Science.gov (United States)

Lilleker, James B; Jones, Matthew S; Mohanraj, Rajiv

2013-11-01

In a significant number of patients developing epilepsy in adult life, the aetiology of their seizures remains unclear. Antibodies directed against the voltage gated potassium channel complex (VGKC Ab) have been identified in various cohorts of patients with epilepsy, although the role of these antibodies in epilepsy pathogenesis is not fully known. We reviewed the notes of 144 patients with unexplained adult onset epilepsy who had been tested for VGKC Abs. We collected data on their clinical syndrome, investigation results and response to treatment. We identified 6 (4.2%) patients who had titres of >400 pM. One of the six patients was positive for LGI1 and another for CASPR2 subunit antibodies. All patients were given immunotherapy and experienced improvement in seizure control. No patient had the clinical syndrome of limbic encephalitis. Patients with otherwise unexplained epilepsy and positive VGKC Abs are a heterogeneous group. In our cohort there was an overall favourable response to immunotherapy but further prospective studies are needed to determine the significance of these antibodies and the optimum treatment regimen for patients. Copyright © 2013 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

The impact of tertiary wastewater treatment on copper and zinc complexation.

Science.gov (United States)

Constantino, C; Gardner, M; Comber, S D W; Scrimshaw, M D; Ellor, B

2015-01-01

Tightening quality standards for European waters has seen a move towards enhanced wastewater treatment technologies such as granulated organic carbon treatment and ozonation. Although these technologies are likely to be successful in degrading certain micro-organic contaminants, these may also destroy compounds which would otherwise complex and render metals significantly less toxic. This study examined the impact of enhanced tertiary treatment on the capacity of organic compounds within sewage effluents to complex copper and zinc. The data show that granulated organic carbon treatment removes a dissolved organic carbon (DOC) fraction that is unimportant to complexation such that no detrimental impact on complexation or metal bioavailability is likely to occur from this treatment type. High concentrations of ozone (>1 mg O3/mg DOC) are, however, likely to impact the complexation capacity for copper although this is unlikely to be important at the concentrations of copper typically found in effluent discharges or in rivers. Ozone treatment did not affect zinc complexation capacity. The complexation profiles of the sewage effluents show these to contain a category of non-humic ligand that appears unaffected by tertiary treatment and which displays a high affinity for zinc, suggesting these may substantially reduce the bioavailability of zinc in effluent discharges. The implication is that traditional metal bioavailability assessment approaches such as the biotic ligand model may overestimate zinc bioavailability in sewage effluents and effluent-impacted waters.

Micro-pigmentation: implications for patients and professionals.

Science.gov (United States)

Collingridge, Kim; Calcluth, Julie

In the UK, reconstructive breast surgery is routinely offered to patients undergoing surgery for breast cancer. The results can be excellent, but without a nipple-areola complex the patient can feel incomplete. In response to patient need, an innovative nurse-led micro-pigmentation service has been developed in the authors' NHS trust, which provides women (and men) an opportunity to complete their reconstruction process. With the use of coloured pigments, micro-pigmentation creates a permanent image of a nipple-areola complex, which improves the aesthetic appearance of the surgically-created breast. As with the development of any new nurse-led innovation, the micro-pigmentation service has professional and client implications. Breast cancer can be devastating and may induce many psychological concerns, not least about body image and sexuality. This article addresses these issues, along with professional matters, such as autonomous practice, role expansion and the blurring of clinical boundaries. These factors are considered in relation to the nursing management of the micro-pigmentation service, where patient autonomy is encouraged to promote acceptance of self-image and closure on the breast cancer experience.

QCD corrections to squark production in e+ e- annihilation in the MSSM with complex parameters

International Nuclear Information System (INIS)

Nguyen Thi Thu Huong; Ha Huy Bang; Nguyen Chinh Cuong; Dao Thi Le Thuy

2004-11-01

We discuss the pair production of scalar quarks in e + e - annihilation within the MSSM with complex parameters. We calculate the SUSY-QCD corrections to the cross section e + e - → q-tilde i q-bar-tilde j (i, j 1, 2) and show that the effect of the CP phases of these complex parameters on the cross section can be quite strong in a large region of the MSSM parameter space. This could have important implications for squarks searches and the MSSM parameter determination in future collider experiments. (author)

Structural studies of f-element complexes with soft donor extractants

International Nuclear Information System (INIS)

Jensen, Mark P.; Bond, Andrew H.; Nash, Kenneth L.

2000-01-01

To better understand the unique features and structural implications of An-soft donor interactions, we used solvent extraction, extended x-ray absorption fine structure (Exafs), and optical spectroscopy to study both the lanthanide and actinide complexes of a series of dialkylphosphinic acid extractants, bis(2,4,4-trimethylpentyl)phosphinic acid, bis(2,4,4-trimethylpentyl)monothiophosphinic acid, and bis(2,4,4- trimethylpentyl)dithiophosphinic acid, which are the primary components of the commercial extractants Cyanex 272, Cyanex 302, and Cyanex 301

Replication-mediated disassociation of replication protein A-XPA complex upon DNA damage: implications for RPA handing off.

Science.gov (United States)

Jiang, Gaofeng; Zou, Yue; Wu, Xiaoming

2012-08-01

RPA (replication protein A), the eukaryotic ssDNA (single-stranded DNA)-binding protein, participates in most cellular processes in response to genotoxic insults, such as NER (nucleotide excision repair), DNA, DSB (double-strand break) repair and activation of cell cycle checkpoint signalling. RPA interacts with XPA (xeroderma pigmentosum A) and functions in early stage of NER. We have shown that in cells the RPA-XPA complex disassociated upon exposure of cells to high dose of UV irradiation. The dissociation required replication stress and was partially attributed to tRPA hyperphosphorylation. Treatment of cells with CPT (camptothecin) and HU (hydroxyurea), which cause DSB DNA damage and replication fork collapse respectively and also leads to the disruption of RPA-XPA complex. Purified RPA and XPA were unable to form complex in vitro in the presence of ssDNA. We propose that the competition-based RPA switch among different DNA metabolic pathways regulates the dissociation of RPA with XPA in cells after DNA damage. The biological significances of RPA-XPA complex disruption in relation with checkpoint activation, DSB repair and RPA hyperphosphorylation are discussed.

Replication-mediated disassociation of replication protein A–XPA complex upon DNA damage: implications for RPA handing off

Science.gov (United States)

Jiang, Gaofeng; Zou, Yue; Wu, Xiaoming

2013-01-01

RPA (replication protein A), the eukaryotic ssDNA (single-stranded DNA)-binding protein, participates in most cellular processes in response to genotoxic insults, such as NER (nucleotide excision repair), DNA, DSB (double-strand break) repair and activation of cell cycle checkpoint signalling. RPA interacts with XPA (xeroderma pigmentosum A) and functions in early stage of NER. We have shown that in cells the RPA–XPA complex disassociated upon exposure of cells to high dose of UV irradiation. The dissociation required replication stress and was partially attributed to tRPA hyperphosphorylation. Treatment of cells with CPT (camptothecin) and HU (hydroxyurea), which cause DSB DNA damage and replication fork collapse respectively and also leads to the disruption of RPA–XPA complex. Purified RPA and XPA were unable to form complex in vitro in the presence of ssDNA. We propose that the competition-based RPA switch among different DNA metabolic pathways regulates the dissociation of RPA with XPA in cells after DNA damage. The biological significances of RPA–XPA complex disruption in relation with checkpoint activation, DSB repair and RPA hyperphosphorylation are discussed. PMID:22578086

Linking structural features of protein complexes and biological function.

Science.gov (United States)

Sowmya, Gopichandran; Breen, Edmond J; Ranganathan, Shoba

2015-09-01

Protein-protein interaction (PPI) establishes the central basis for complex cellular networks in a biological cell. Association of proteins with other proteins occurs at varying affinities, yet with a high degree of specificity. PPIs lead to diverse functionality such as catalysis, regulation, signaling, immunity, and inhibition, playing a crucial role in functional genomics. The molecular principle of such interactions is often elusive in nature. Therefore, a comprehensive analysis of known protein complexes from the Protein Data Bank (PDB) is essential for the characterization of structural interface features to determine structure-function relationship. Thus, we analyzed a nonredundant dataset of 278 heterodimer protein complexes, categorized into major functional classes, for distinguishing features. Interestingly, our analysis has identified five key features (interface area, interface polar residue abundance, hydrogen bonds, solvation free energy gain from interface formation, and binding energy) that are discriminatory among the functional classes using Kruskal-Wallis rank sum test. Significant correlations between these PPI interface features amongst functional categories are also documented. Salt bridges correlate with interface area in regulator-inhibitors (r = 0.75). These representative features have implications for the prediction of potential function of novel protein complexes. The results provide molecular insights for better understanding of PPIs and their relation to biological functions. © 2015 The Protein Society.

{alpha},{beta}-Unsaturated Fischer carbene complexes as chemical multitalents

Energy Technology Data Exchange (ETDEWEB)

Meijere, A. de [Institut fuer Organische Chemie der George-August-Universitaet Goettingen (Germany)

1995-12-31

The well established reaction of {alpha},{beta}-unsaturated Fischer carbenechromium complexes 6(R{sup 1} = H) with alkynes normally proceeds with carbonyl insertion to yield 4-alkoxyphenols 9. Led by the incidental formation of a cyclopentadiene 3 from certain {beta}-aminosubstituted complexes 6(X = NR{sub 2}{sup 3}, R{sup 1} = cPr) the authors have studied the influences of the nature of substituents (R{sup 1}, X on 6; R{sub L}, R{sub S} in the alkyne; R{sup 3} in the amino group), solvents, and temperature on the outcome of the reaction. Imino substitution on complexes 6 leads to 2H-pyrroles 1, a free primary amino group (X = NH{sub 2}) to pyridines 5, and bulky substituents R{sup 1} to cyclopenta[b]pyrans 8 with double insertion of an alkyne. Eventually, appropriate conditions have been developed which permit to selectively prepare either 3-alkoxy-5-(dialkylamino)cyclopentadienes 3 (as synthetic equivalents of cyclopentenones 4), 5-(dialkylaminomethylene)cyclopent-2-enones 7, 3-alkoxy-2-(1{prime}-morpholino-1{prime}-alkenyl)cyclopent-2-enones 10, and 2-acyl-3-(dialkylamino)cyclopent-2-enones 11 from easily accessible carbene complexes 6 (X = NR{sub 2}{sup 3}) in high yields. Mechanistic aspects and implications of these novel transformations will be discussed.

Re-Making the Incarceration-Nation: Naming the Participation of Schools in Our Prison Industrial Complex

Science.gov (United States)

Meiners, Erica R.; Reyes, Karen Benita

2008-01-01

In this article, the authors seek to contribute to the growing engagement with the school-prison nexus by considering two, perhaps less obvious, factors that implicate schools in the business of the prison industrial complex (PIC)--the examples of gentrification and sex offender registries. By unpacking some of the rhetoric that surrounds…

Communication complexity and information complexity

Science.gov (United States)

Pankratov, Denis

Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

MARKETING IMPLICATION IN WINE ECONOMY

Directory of Open Access Journals (Sweden)

Ştefan MATEI

2014-11-01

Full Text Available The wine, a very complex product in viticulture, has proved its tremendous importance not only to the individual but rational nutrition and increasing national income of a country cultivators (evidenced by the upward trend of the share of crop production horticulture and viticulture in the global economy agricultural. More interesting is, given the continued growth in the number of scientific publications and their quality (at least since the 1980s - where "wine" is the centerpiece of these studies - we can not but be witnessing a growing interest more to this "potion" and found that the growing popularity of wine in the science reveals the emergence of a new academic field, ie "wine economy" (or wine-economy. This study aims to make a foray into "wine economy" and to outline some of the implications of marketing in this area.

Public health implications of complex emergencies and natural disasters.

Science.gov (United States)

Culver, Amanda; Rochat, Roger; Cookson, Susan T

2017-01-01

During the last decade, conflict or natural disasters have displaced unprecedented numbers of persons. This leads to conditions prone to outbreaks that imperil the health of displaced persons and threaten global health security. Past literature has minimally examined the association of communicable disease outbreaks with complex emergencies (CEs) and natural disasters (NDs). To examine this association, we identified CEs and NDs using publicly available datasets from the Center for Research on the Epidemiology of Disasters and United Nations Flash and Consolidated Appeals archive for 2005-2014. We identified outbreaks from World Health Organization archives. We compared findings to identify overlap of outbreaks, including their types (whether or not of a vaccine-preventable disease), and emergency event types (CE, ND, or Both) by country and year using descriptive statistics and measure of association. There were 167 CEs, 912 NDs, 118 events linked to 'Both' types of emergencies, and 384 outbreaks. Of CEs, 43% were associated with an outbreak; 24% NDs were associated with an outbreak; and 36% of 'Both' types of emergencies were associated with an outbreak. Africa was disproportionately affected, where 67% of total CEs, 67% of 'Both' events (CE and ND), and 46% of all outbreaks occurred for the study period. The odds ratio of a vaccine-preventable outbreak occurring in a CE versus an ND was 4.14 (95% confidence limits 1.9, 9.4). CEs had greater odds of being associated with outbreaks compared with NDs. Moreover, CEs had high odds of a vaccine-preventable disease causing that outbreak. Focusing on better vaccine coverage could reduce CE-associated morbidity and mortality by preventing outbreaks from spreading.

Genetics of Atrial Fibrillation and Possible Implications for Ischemic Stroke

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Robin Lemmens

2011-01-01

Full Text Available Atrial fibrillation is the most common cardiac arrhythmia mainly caused by valvular, ischemic, hypertensive, and myopathic heart disease. Atrial fibrillation can occur in families suggesting a genetic background especially in younger subjects. Additionally recent studies have identified common genetic variants to be associated with atrial fibrillation in the general population. This cardiac arrhythmia has important public health implications because of its main complications: congestive heart failure and ischemic stroke. Since atrial fibrillation can result in ischemic stroke, one might assume that genetic determinants of this cardiac arrhythmia are also implicated in cerebrovascular disease. Ischemic stroke is a multifactorial, complex disease where multiple environmental and genetic factors interact. Whether genetic variants associated with a risk factor for ischemic stroke also increase the risk of a particular vascular endpoint still needs to be confirmed in many cases. Here we review the current knowledge on the genetic background of atrial fibrillation and the consequences for cerebrovascular disease.

Complex Signal Kurtosis and Independent Component Analysis for Wideband Radio Frequency Interference Detection

Science.gov (United States)

Schoenwald, Adam; Mohammed, Priscilla; Bradley, Damon; Piepmeier, Jeffrey; Wong, Englin; Gholian, Armen

2016-01-01

Radio-frequency interference (RFI) has negatively implicated scientific measurements across a wide variation passive remote sensing satellites. This has been observed in the L-band radiometers SMOS, Aquarius and more recently, SMAP [1, 2]. RFI has also been observed at higher frequencies such as K band [3]. Improvements in technology have allowed wider bandwidth digital back ends for passive microwave radiometry. A complex signal kurtosis radio frequency interference detector was developed to help identify corrupted measurements [4]. This work explores the use of ICA (Independent Component Analysis) as a blind source separation technique to pre-process radiometric signals for use with the previously developed real and complex signal kurtosis detectors.

Comment on "Defocusing complex short-pulse equation and its multi-dark-soliton solution"

Science.gov (United States)

Youssoufa, Saliou; Kuetche, Victor K.; Kofane, Timoleon C.

2017-08-01

In their recent paper, Feng et al. [Phys. Rev. E 93, 052227 (2016), 10.1103/PhysRevE.93.052227] proposed a complex short-pulse equation of both focusing and defocusing types. They studied in detail the defocusing case and derived its multi-dark-soliton solutions. Nonetheless, from a physical viewpoint in order to better and deeply understand their genuine implications, we find it useful to provide a real and proper background for the derivation of the previous evolution system while showing that the expression of the nonlinear electric polarization the above authors used in their scheme is not suitable for getting the defocusing complex short-pulse equation.

Nanoscale patterning of two metals on silicon surfaces using an ABC triblock copolymer template.

Science.gov (United States)

Aizawa, Masato; Buriak, Jillian M

2006-05-03

Patterning technologically important semiconductor interfaces with nanoscale metal films is important for applications such as metallic interconnects and sensing applications. Self-assembling block copolymer templates are utilized to pattern an aqueous metal reduction reaction, galvanic displacement, on silicon surfaces. Utilization of a triblock copolymer monolayer film, polystyrene-block-poly(2-vinylpyridine)-block-poly(ethylene oxide) (PS-b-P2VP-b-PEO), with two blocks capable of selective transport of different metal complexes to the surface (PEO and P2VP), allows for chemical discrimination and nanoscale patterning. Different regions of the self-assembled structure discriminate between metal complexes at the silicon surface, at which time they undergo the spontaneous reaction at the interface. Gold deposition from gold(III) compounds such as HAuCl4(aq) in the presence of hydrofluoric acid mirrors the parent block copolymer core structure, whereas silver deposition from Ag(I) salts such as AgNO3(aq) does the opposite, localizing exclusively under the corona. By carrying out gold deposition first and silver second, sub-100-nm gold features surrounded by silver films can be produced. The chemical selectivity was extended to other metals, including copper, palladium, and platinum. The interfaces were characterized by a variety of methods, including scanning electron microscopy, scanning Auger microscopy, X-ray photoelectron spectroscopy, and atomic force microscopy.

Implications of parent-child relationships for emerging adults' subjective feelings about adulthood.

Science.gov (United States)

Lindell, Anna K; Campione-Barr, Nicole; Killoren, Sarah E

2017-10-01

Little is known about the role of parents in promoting their children's successful transition to adulthood, particularly for college students who may maintain stronger ties to parents than other emerging adults. The present study therefore investigated longitudinal implications of parent-child relationship qualities during emerging adults' first year of college for their feelings about the upcoming transition to adulthood 3 years later, as well as implications of 3 types of parental control (behavioral control, psychological control, helicopter parenting) for these associations. Multilevel models indicated that emerging adults who reported less negativity in their relationships with mothers and fathers felt more like adults 3 years later compared with emerging adults with low-quality relationships, while high levels of psychological control and helicopter parenting had detrimental implications for their vocational identity development and perceived competence regarding their transition to adulthood. However, nuanced interactions between parent-child relationship quality and parental control indicated that behavioral control had positive implications for outcomes if it occurred within the context of high-quality relationships, or when utilized with sons. The present study highlights the complex role that parents may play during college students' transition to adulthood, and future work should continue to examine ways that clinicians can incorporate parents as a potential resource for promoting emerging adults' successful transition to adulthood and the workforce. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Localization of the AP-3 adaptor complex defines a novel endosomal exit site for lysosomal membrane proteins

NARCIS (Netherlands)

Peden, A.A.; Oorschot, V.; Hesser, B.A.; Austin, C.D.; Scheller, R.H.; Klumperman, J.

2004-01-01

The adaptor protein (AP) 3 adaptor complex has been implicated in the transport of lysosomal membrane proteins, but its precise site of action has remained controversial. Here, we show by immuno-electron microscopy that AP-3 is associated with budding profiles evolving from a tubular endosomal

Service quality and maturity of health care organizations through the lens of Complexity Leadership Theory.

Science.gov (United States)

Horvat, Ana; Filipovic, Jovan

2018-02-01

This research focuses on Complexity Leadership Theory and the relationship between leadership-examined through the lens of Complexity Leadership Theory-and organizational maturity as an indicator of the performance of health organizations. The research adopts a perspective that conceptualizes organizations as complex adaptive systems and draws upon a survey of opinion of 189 managers working in Serbian health organizations. As the results indicate a dependency between functions of leadership and levels of the maturity of health organizations, we propose a model that connects the two. The study broadens our understanding of the implications of complexity thinking and its reflection on leadership functions and overall organizational performance. The correlations between leadership functions and maturity could have practical applications in policy processing, thus improving the quality of outcomes and the overall level of service quality. © 2017 John Wiley & Sons, Ltd.

Polar localization of Escherichia coli chemoreceptors requires an intact Tol–Pal complex

Science.gov (United States)

Santos, Thiago M. A.; Lin, Ti-Yu; Rajendran, Madhusudan; Anderson, Samantha M.; Weibel, Douglas B.

2014-01-01

Summary Subcellular biomolecular localization is critical for the metabolic and structural properties of the cell. The functional implications of the spatiotemporal distribution of protein complexes during the bacterial cell cycle have long been acknowledged; however, the molecular mechanisms for generating and maintaining their dynamic localization in bacteria are not completely understood. Here we demonstrate that the trans-envelope Tol–Pal complex, a widely conserved component of the cell envelope of Gram-negative bacteria, is required to maintain the polar positioning of chemoreceptor clusters in Escherichia coli. Localization of the chemoreceptors was independent of phospholipid composition of the membrane and the curvature of the cell wall. Instead, our data indicate that chemoreceptors interact with components of the Tol–Pal complex and that this interaction is required to polarly localize chemoreceptor clusters. We found that disruption of the Tol–Pal complex perturbs the polar localization of chemoreceptors, alters cell motility, and affects chemotaxis. We propose that the E. coli Tol–Pal complex restricts mobility of the chemoreceptor clusters at the cell poles and may be involved in regulatory mechanisms that co-ordinate cell division and segregation of the chemosensory machinery. PMID:24720726

Implications of agricultural transitions and urbanization for ecosystem services.

Science.gov (United States)

Cumming, Graeme S; Buerkert, Andreas; Hoffmann, Ellen M; Schlecht, Eva; von Cramon-Taubadel, Stephan; Tscharntke, Teja

2014-11-06

Historically, farmers and hunter-gatherers relied directly on ecosystem services, which they both exploited and enjoyed. Urban populations still rely on ecosystems, but prioritize non-ecosystem services (socioeconomic). Population growth and densification increase the scale and change the nature of both ecosystem- and non-ecosystem-service supply and demand, weakening direct feedbacks between ecosystems and societies and potentially pushing social-ecological systems into traps that can lead to collapse. The interacting and mutually reinforcing processes of technological change, population growth and urbanization contribute to over-exploitation of ecosystems through complex feedbacks that have important implications for sustainable resource use.

Supporting Sensemaking of Complex Objects with Visualizations: Visibility and Complementarity of Interactions

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Kamran Sedig

2016-10-01

Full Text Available Making sense of complex objects is difficult, and typically requires the use of external representations to support cognitive demands while reasoning about the objects. Visualizations are one type of external representation that can be used to support sensemaking activities. In this paper, we investigate the role of two design strategies in making the interactive features of visualizations more supportive of users’ exploratory needs when trying to make sense of complex objects. These two strategies are visibility and complementarity of interactions. We employ a theoretical framework concerned with human–information interaction and complex cognitive activities to inform, contextualize, and interpret the effects of the design strategies. The two strategies are incorporated in the design of Polyvise, a visualization tool that supports making sense of complex four-dimensional geometric objects. A mixed-methods study was conducted to evaluate the design strategies and the overall usability of Polyvise. We report the findings of the study, discuss some implications for the design of visualization tools that support sensemaking of complex objects, and propose five design guidelines. We anticipate that our results are transferrable to other contexts, and that these two design strategies can be used broadly in visualization tools intended to support activities with complex objects and information spaces.

Complex singlet extension of the standard model

International Nuclear Information System (INIS)

Barger, Vernon; McCaskey, Mathew; Langacker, Paul; Ramsey-Musolf, Michael; Shaughnessy, Gabe

2009-01-01

We analyze a simple extension of the standard model (SM) obtained by adding a complex singlet to the scalar sector (cxSM). We show that the cxSM can contain one or two viable cold dark matter candidates and analyze the conditions on the parameters of the scalar potential that yield the observed relic density. When the cxSM potential contains a global U(1) symmetry that is both softly and spontaneously broken, it contains both a viable dark matter candidate and the ingredients necessary for a strong first order electroweak phase transition as needed for electroweak baryogenesis. We also study the implications of the model for discovery of a Higgs boson at the Large Hadron Collider.

High Grade Glioma Mimicking Voltage Gated Potassium Channel Complex Associated Antibody Limbic Encephalitis

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Dilan Athauda

2014-01-01

Full Text Available Though raised titres of voltage gated potassium channel (VGKC complex antibodies have been occasionally associated with extracranial tumours, mainly presenting as Morvan's Syndrome or neuromyotonia, they have not yet been reported to be associated with an intracranial malignancy. This is especially important as misdiagnosis of these conditions and delay of the appropriate treatment can have important prognostic implications. We describe a patient with a high grade glioma presenting with clinical, radiological, and serological features consistent with the diagnosis of VGKC antibody associated limbic encephalitis (LE. This is the first association between a primary brain tumour and high titre of VGKC complex antibodies. Clinicoradiological progression despite effective immunosuppressive treatment should prompt clinicians to look for alternative diagnoses. Further studies to elucidate a possible association between VGKC complex and other surface antigen antibodies with primary brain tumours should be carried out.

High grade glioma mimicking voltage gated potassium channel complex associated antibody limbic encephalitis.

Science.gov (United States)

Athauda, Dilan; Delamont, R S; Pablo-Fernandez, E De

2014-01-01

Though raised titres of voltage gated potassium channel (VGKC) complex antibodies have been occasionally associated with extracranial tumours, mainly presenting as Morvan's Syndrome or neuromyotonia, they have not yet been reported to be associated with an intracranial malignancy. This is especially important as misdiagnosis of these conditions and delay of the appropriate treatment can have important prognostic implications. We describe a patient with a high grade glioma presenting with clinical, radiological, and serological features consistent with the diagnosis of VGKC antibody associated limbic encephalitis (LE). This is the first association between a primary brain tumour and high titre of VGKC complex antibodies. Clinicoradiological progression despite effective immunosuppressive treatment should prompt clinicians to look for alternative diagnoses. Further studies to elucidate a possible association between VGKC complex and other surface antigen antibodies with primary brain tumours should be carried out.

Single-stranded nucleic acids promote SAMHD1 complex formation.

Science.gov (United States)

Tüngler, Victoria; Staroske, Wolfgang; Kind, Barbara; Dobrick, Manuela; Kretschmer, Stefanie; Schmidt, Franziska; Krug, Claudia; Lorenz, Mike; Chara, Osvaldo; Schwille, Petra; Lee-Kirsch, Min Ae

2013-06-01

SAM domain and HD domain-containing protein 1 (SAMHD1) is a dGTP-dependent triphosphohydrolase that degrades deoxyribonucleoside triphosphates (dNTPs) thereby limiting the intracellular dNTP pool. Mutations in SAMHD1 cause Aicardi-Goutières syndrome (AGS), an inflammatory encephalopathy that mimics congenital viral infection and that phenotypically overlaps with the autoimmune disease systemic lupus erythematosus. Both disorders are characterized by activation of the antiviral cytokine interferon-α initiated by immune recognition of self nucleic acids. Here we provide first direct evidence that SAMHD1 associates with endogenous nucleic acids in situ. Using fluorescence cross-correlation spectroscopy, we demonstrate that SAMHD1 specifically interacts with ssRNA and ssDNA and establish that nucleic acid-binding and formation of SAMHD1 complexes are mutually dependent. Interaction with nucleic acids and complex formation do not require the SAM domain, but are dependent on the HD domain and the C-terminal region of SAMHD1. We finally demonstrate that mutations associated with AGS exhibit both impaired nucleic acid-binding and complex formation implicating that interaction with nucleic acids is an integral aspect of SAMHD1 function.

Dysfunction of Protein Quality Control in Parkinsonism–Dementia Complex of Guam

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Bert M. Verheijen

2018-03-01

Full Text Available Guam parkinsonism–dementia complex (G-PDC is an enigmatic neurodegenerative disease that is endemic to the Pacific island of Guam. G-PDC patients are clinically characterized by progressive cognitive impairment and parkinsonism. Neuropathologically, G-PDC is characterized by abundant neurofibrillary tangles, which are composed of hyperphosphorylated tau, marked deposition of 43-kDa TAR DNA-binding protein, and neuronal loss. Although both genetic and environmental factors have been implicated, the etiology and pathogenesis of G-PDC remain unknown. Recent neuropathological studies have provided new clues about the pathomechanisms involved in G-PDC. For example, deposition of abnormal components of the protein quality control system in brains of G-PDC patients indicates a role for proteostasis imbalance in the disease. This opens up promising avenues for new research on G-PDC and could have important implications for the study of other neurodegenerative disorders.

Enabling Requirements-Based Programming for Highly-Dependable Complex Parallel and Distributed Systems

Science.gov (United States)

Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.

2005-01-01

The manual application of formal methods in system specification has produced successes, but in the end, despite any claims and assertions by practitioners, there is no provable relationship between a manually derived system specification or formal model and the customer's original requirements. Complex parallel and distributed system present the worst case implications for today s dearth of viable approaches for achieving system dependability. No avenue other than formal methods constitutes a serious contender for resolving the problem, and so recognition of requirements-based programming has come at a critical juncture. We describe a new, NASA-developed automated requirement-based programming method that can be applied to certain classes of systems, including complex parallel and distributed systems, to achieve a high degree of dependability.

Cholesterol depletion of enterocytes. Effect on the Golgi complex and apical membrane trafficking

DEFF Research Database (Denmark)

Hansen, Gert Helge; Niels-Christiansen, L L; Thorsen, Evy

2000-01-01

Intestinal brush border enzymes, including aminopeptidase N and sucrase-isomaltase, are associated with "rafts" (membrane microdomains rich in cholesterol and sphingoglycolipids). To assess the functional role of rafts in the present work, we studied the effect of cholesterol depletion on apical......, the rates of the Golgi-associated complex glycosylation and association with rafts of newly synthesized aminopeptidase N were reduced, and less of the enzyme had reached the brush border membrane after 2 h of labeling. In contrast, the basolateral Na(+)/K(+)-ATPase was neither missorted nor raft......-associated. Our results implicate the Golgi complex/trans-Golgi network in raft formation and suggest a close relationship between this event and apical membrane trafficking....

Complexity of Human Antibody Response to Dengue Virus: Implication for Vaccine Development.

Science.gov (United States)

Tsai, Wen-Yang; Lin, Hong-En; Wang, Wei-Kung

2017-01-01

The four serotypes of dengue virus (DENV) are the leading cause of arboviral diseases in humans. Decades of efforts have made remarkable progress in dengue vaccine development. Despite the first dengue vaccine (dengvaxia from Sanofi Pasteur), a live-attenuated tetravalent chimeric yellow fever-dengue vaccine, has been licensed by several countries since 2016, its overall moderate efficacy (56.5-60.8%) in the presence of neutralizing antibodies during the Phase 2b and 3 trials, lower efficacy among dengue naïve compared with dengue experienced individuals, and increased risk of hospitalization among young children during the follow-up highlight the need for a better understanding of humoral responses after natural DENV infection. Recent studies of more than 300 human monoclonal antibodies (mAbs) against DENV have led to the discovery of several novel epitopes on the envelope protein recognized by potent neutralizing mAbs. This information together with in-depth studies on polyclonal sera and B-cells following natural DENV infection has tremendous implications for better immunogen design for a safe and effective dengue vaccine. This review outlines the progress in our understanding of mouse mAbs, human mAbs, and polyclonal sera against DENV envelope and precursor membrane proteins, two surface proteins involved in vaccine development, following natural infection; analyses of these discoveries have provided valuable insight into new strategies involving molecular technology to induce more potent neutralizing antibodies and less enhancing antibodies for next-generation dengue vaccine development.

Complexity of Human Antibody Response to Dengue Virus: Implication for Vaccine Development

Directory of Open Access Journals (Sweden)

Wen-Yang Tsai

2017-07-01

Full Text Available The four serotypes of dengue virus (DENV are the leading cause of arboviral diseases in humans. Decades of efforts have made remarkable progress in dengue vaccine development. Despite the first dengue vaccine (dengvaxia from Sanofi Pasteur, a live-attenuated tetravalent chimeric yellow fever-dengue vaccine, has been licensed by several countries since 2016, its overall moderate efficacy (56.5–60.8% in the presence of neutralizing antibodies during the Phase 2b and 3 trials, lower efficacy among dengue naïve compared with dengue experienced individuals, and increased risk of hospitalization among young children during the follow-up highlight the need for a better understanding of humoral responses after natural DENV infection. Recent studies of more than 300 human monoclonal antibodies (mAbs against DENV have led to the discovery of several novel epitopes on the envelope protein recognized by potent neutralizing mAbs. This information together with in-depth studies on polyclonal sera and B-cells following natural DENV infection has tremendous implications for better immunogen design for a safe and effective dengue vaccine. This review outlines the progress in our understanding of mouse mAbs, human mAbs, and polyclonal sera against DENV envelope and precursor membrane proteins, two surface proteins involved in vaccine development, following natural infection; analyses of these discoveries have provided valuable insight into new strategies involving molecular technology to induce more potent neutralizing antibodies and less enhancing antibodies for next-generation dengue vaccine development.

A critical review of principal traffic noise models: Strategies and implications

Energy Technology Data Exchange (ETDEWEB)

Garg, Naveen, E-mail: ngarg@mail.nplindia.ernet.in [Apex Level Standards and Industrial Metrology Division, CSIR-National Physical Laboratory, New Delhi 110012 (India); Department of Mechanical, Production and Industrial Engineering, Delhi Technological University, Delhi 110042 (India); Maji, Sagar [Department of Mechanical, Production and Industrial Engineering, Delhi Technological University, Delhi 110042 (India)

2014-04-01

The paper presents an exhaustive comparison of principal traffic noise models adopted in recent years in developed nations. The comparison is drawn on the basis of technical attributes including source modelling and sound propagation algorithms. Although the characterization of source in terms of rolling and propulsion noise in conjunction with advanced numerical methods for sound propagation has significantly reduced the uncertainty in traffic noise predictions, the approach followed is quite complex and requires specialized mathematical skills for predictions which is sometimes quite cumbersome for town planners. Also, it is sometimes difficult to follow the best approach when a variety of solutions have been proposed. This paper critically reviews all these aspects pertaining to the recent models developed and adapted in some countries and also discusses the strategies followed and implications of these models. - Highlights: • Principal traffic noise models developed are reviewed. • Sound propagation algorithms used in traffic noise models are compared. • Implications of models are discussed.

EPR study of complex formation between copper (II) ions and sympathomimetic amines in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Preoteasa, E.A. [Inst. of Atomic Physics, IFIN, Bucharest (Romania); Duliu, O.G.; Grecu, V.V. [Bucharest, Univ. (Romania). Dept. of Atomic and Nuclear Physics

1997-07-01

The complex formation between sympathomimetic amines (SA): adrenaline (AD), noradrenaline (NA), dopamine (DA), ephedrine (ED) and p-tyramine (pTA), and Cu(II) ion in aqueous solution has been studied by X-band EPR at room temperature. Excepting pTA, all investigated SA yielded two types of complexes in different pH domains. All complexes consistent with a ligand fields having a distorted octahedral symmetry, i.e., hexacoordination of Cu(II). The covalence coefficient calculated from the isotropic g and A values has shown strong ionic sigma-type ligand bonds. A structural model with the Cu(II) ion bound by four catecholic O(hydroxy) atoms for the low pH complexes of AD, NA and DA is proposed. For the high pH complexes of the former compounds as well as for both Ed complexes, the authors suppose Cu(II) bound by two N (amino) and two O (hydroxy) atoms. The spectra are consistent to water binding on the longitudinal octahedron axis in all compounds excepting the high pH complex of Ed, where OH2- ions are bound. Possible implications for the SA-cell receptors interactions are discussed.

The biology of skin wetness perception and its implications in manual function and for reproducing complex somatosensory signals in neuroprosthetics.

Science.gov (United States)

Filingeri, Davide; Ackerley, Rochelle

2017-04-01

Our perception of skin wetness is generated readily, yet humans have no known receptor (hygroreceptor) to signal this directly. It is easy to imagine the sensation of water running over our hands or the feel of rain on our skin. The synthetic sensation of wetness is thought to be produced from a combination of specific skin thermal and tactile inputs, registered through thermoreceptors and mechanoreceptors, respectively. The present review explores how thermal and tactile afference from the periphery can generate the percept of wetness centrally. We propose that the main signals include information about skin cooling, signaled primarily by thinly myelinated thermoreceptors, and rapid changes in touch, through fast-conducting, myelinated mechanoreceptors. Potential central sites for integration of these signals, and thus the perception of skin wetness, include the primary and secondary somatosensory cortices and the insula cortex. The interactions underlying these processes can also be modeled to aid in understanding and engineering the mechanisms. Furthermore, we discuss the role that sensing wetness could play in precision grip and the dexterous manipulation of objects. We expand on these lines of inquiry to the application of the knowledge in designing and creating skin sensory feedback in prosthetics. The addition of real-time, complex sensory signals would mark a significant advance in the use and incorporation of prosthetic body parts for amputees in everyday life. NEW & NOTEWORTHY Little is known about the underlying mechanisms that generate the perception of skin wetness. Humans have no specific hygroreceptor, and thus temperature and touch information combine to produce wetness sensations. The present review covers the potential mechanisms leading to the perception of wetness, both peripherally and centrally, along with their implications for manual function. These insights are relevant to inform the design of neuroengineering interfaces, such as sensory

Chronic pain as a manifestation of potassium channel-complex autoimmunity.

Science.gov (United States)

Klein, Christopher J; Lennon, Vanda A; Aston, Paula A; McKeon, Andrew; Pittock, Sean J

2012-09-11

Autoantibodies targeting voltage-gated potassium channel (VGKC) complexes cause a spectrum of neuronal hyperexcitability disorders. We investigated pain as a manifestation of VGKC-complex autoimmunity. We reviewed the prevalence and characteristics of pain in VGKC-complex-immunoglobulin G (IgG)-seropositive patients in 25 months of comprehensive service testing for neural autoantibodies, subtyped positive sera for LGI1-IgG and CASPR2-IgG specificities, and reviewed pain prevalence in autoimmune control patients. VGKC-complex-IgG was identified in 1,992 patients of 54,853 tested (4%). Of 316 evaluated neurologically at Mayo Clinic, 159 (50%) had pain, in isolation (28%) or with accompanying neurologic manifestations (72%), and not attributable to alternative cause. Pain was subacute in onset, chronic in course, neuropathic, nociceptive, regional, or diffuse and sometimes attributed to fibromyalgia (6%) or psychogenic cause (13%). Most patients had normal peripheral nervous system function, measured by neuropathy impairment scores and nerve conduction. Evidence of neuronal hyperexcitability (hyperhidrosis, quantitative heat-pain hyperalgesia, or electromyographic excitability) was 25-fold more common in pain patients. Pain management required multiple medications in 70% (narcotics, 30%); 13 of 16 patients reported pain relief with immunotherapy. Pain was significantly associated with CASPR2-IgG-positivity (16% positive with pain, 7% without pain; p = 0.014) but not with LGI1-IgG. Less than 10% of 167 patients with neural autoantibodies other than VGKC-complex-IgG reported pain. Chronic idiopathic pain is a syndromic manifestation of VGKC-complex autoimmunity. Hyperexcitability of nociceptive pathways is implicated. CASPR2-IgG significantly associates with pain, but in most patients the antigenic VGKC-complex molecule remains to be determined. VGKC-complex autoimmunity represents an important new direction for pain research and therapy.

DEVELOPING INDUSTRIAL ROBOT SIMULATION MODEL TUR10-K USING “UNIVERSAL MECHANISM” SOFTWARE COMPLEX

Directory of Open Access Journals (Sweden)

Vadim Vladimirovich Chirkov

2018-02-01

Full Text Available Manipulation robots are complex spatial mechanical systems having five or six degrees of freedom, and sometimes more. For this reason, modeling manipulative robots movement, even in the kinematic formulation, is a complex mathematical task. If one moves from kinematic modeling of motion to dynamic modeling then there must be taken into account the inertial properties of the modeling object. In this case, analytical constructing of such a complex object mathematical model as a manipulation robot becomes practically impossible. Therefore, special computer-aided design systems, called CAE-systems, are used for modeling complex mechanical systems. The purpose of the paper is simulation model construction of a complex mechanical system, such as the industrial robot TUR10-K, to obtain its dynamic characteristics. Developing such models makes it possible to reduce the complexity of designing complex systems process and to obtain the necessary characteristics. Purpose. Developing the simulation model of the industrial robot TUR10-K and obtaining dynamic characteristics of the mechanism. Methodology: the article is used a computer simulation method. Results: There is obtained the simulation model of the robot and its dynamic characteristics. Practical implications: the results can be used in the mechanical systems design and various simulation models.

Photocatalysis over TiO/sub 2/ supported on a glass substrate

Energy Technology Data Exchange (ETDEWEB)

Serpone, N; Borgarello, E; Harris, R; Cahill, P; Borgarello, M; Pelizzetti, E

1986-10-01

TiO/sub 2/ has been prepared and simultaneously embedded onto 3-4 mm glass beads by high temperature decomposition of titanium(IV) alkoxides in alcoholic media. The metal oxide acts as a semiconductor upon irradiation with AM1 simulated sunlight as demonstrated by the formation of the methylviologen MV/sup +./ radical in aqueous/methanolic media. The photocatalytic activity of the TiO/sub 2//glass beads material has been assessed by two principal light-driven processes: photoreduction of gold(III), and photodegradation of a chlorinated phenol. The potential utility of this device is discussed. 12 refs.

In vivo measurements of the triceps surae complex architecture in man: implications for muscle function

NARCIS (Netherlands)

Maganaris, C.N.; Baltzopoulos, V.; Sargeant, A.J.

1998-01-01

1. The objectives of this study were to (1) quantify experimentally in vivo changes in pennation angle, fibre length and muscle thickness in the triceps surae complex in man in response to changes in ankle position and isometric plantarflexion moment and (2) compare changes in the above muscle

Understanding and quantifying cognitive complexity level in mathematical problem solving items

Directory of Open Access Journals (Sweden)

SUSAN E. EMBRETSON

2008-09-01

Full Text Available The linear logistic test model (LLTM; Fischer, 1973 has been applied to a wide variety of new tests. When the LLTM application involves item complexity variables that are both theoretically interesting and empirically supported, several advantages can result. These advantages include elaborating construct validity at the item level, defining variables for test design, predicting parameters of new items, item banking by sources of complexity and providing a basis for item design and item generation. However, despite the many advantages of applying LLTM to test items, it has been applied less often to understand the sources of complexity for large-scale operational test items. Instead, previously calibrated item parameters are modeled using regression techniques because raw item response data often cannot be made available. In the current study, both LLTM and regression modeling are applied to mathematical problem solving items from a widely used test. The findings from the two methods are compared and contrasted for their implications for continued development of ability and achievement tests based on mathematical problem solving items.

Characterization and reactivity of the weakly bound complexes of the [H, N, S]{sup −} anionic system with astrophysical and biological implications

Energy Technology Data Exchange (ETDEWEB)

Trabelsi, T.; Ajili, Y.; Ben Yaghlane, S.; Jaidane, N.-E. [Laboratoire de Spectroscopie Atomique, Moléculaire et Applications–LSAMA, Université de Tunis El Manar, Tunis (Tunisia); Mogren Al-Mogren, M. [Chemistry Department, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Francisco, J. S. [Department of Chemistry and Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana 47906 (United States); Hochlaf, M., E-mail: hochlaf@univ-mlv.fr [Laboratoire Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 Blvd. Descartes, 77454 Marne-la-Vallée (France)

2015-07-21

We investigate the lowest electronic states of doublet and quartet spin multiplicity states of HNS{sup −} and HSN{sup −} together with their parent neutral triatomic molecules. Computations were performed using highly accurate ab initio methods with a large basis set. One-dimensional cuts of the full-dimensional potential energy surfaces (PESs) along the interatomic distances and bending angle are presented for each isomer. Results show that the ground anionic states are stable with respect to the electron detachment process and that the long range parts of the PESs correlating to the SH{sup −} + N, SN{sup −} + H, SN + H{sup −}, NH + S{sup −}, and NH{sup −} + S are bound. In addition, we predict the existence of long-lived weakly bound anionic complexes that can be formed after cold collisions between SN{sup −} and H or SH{sup −} and N. The implications for the reactivity of these species are discussed; specifically, it is shown that the reactions involving SH{sup −}, SN{sup −}, and NH{sup −} lead either to the formation of HNS{sup −} or HSN{sup −} in their electronic ground states or to autodetachment processes. Thus, providing an explanation for why the anions, SH{sup −}, SN{sup −}, and NH{sup −}, have limiting detectability in astrophysical media despite the observation of their corresponding neutral species. In a biological context, we suggest that HSN{sup −} and HNS{sup −} should be incorporated into H{sub 2}S-assisted heme-catalyzed reduction mechanism of nitrites in vivo.

A marketing mix model for a complex and turbulent environment

Directory of Open Access Journals (Sweden)

R. B. Mason

2007-12-01

Full Text Available Purpose: This paper is based on the proposition that the choice of marketing tactics is determined, or at least significantly influenced, by the nature of the company’s external environment. It aims to illustrate the type of marketing mix tactics that are suggested for a complex and turbulent environment when marketing and the environment are viewed through a chaos and complexity theory lens. Design/Methodology/Approach: Since chaos and complexity theories are proposed as a good means of understanding the dynamics of complex and turbulent markets, a comprehensive review and analysis of literature on the marketing mix and marketing tactics from a chaos and complexity viewpoint was conducted. From this literature review, a marketing mix model was conceptualised. Findings: A marketing mix model considered appropriate for success in complex and turbulent environments was developed. In such environments, the literature suggests destabilising marketing activities are more effective, whereas stabilising type activities are more effective in simple, stable environments. Therefore the model proposes predominantly destabilising type tactics as appropriate for a complex and turbulent environment such as is currently being experienced in South Africa. Implications: This paper is of benefit to marketers by emphasising a new way to consider the future marketing activities of their companies. How this model can assist marketers and suggestions for research to develop and apply this model are provided. It is hoped that the model suggested will form the basis of empirical research to test its applicability in the turbulent South African environment. Originality/Value: Since businesses and markets are complex adaptive systems, using complexity theory to understand how to cope in complex, turbulent environments is necessary, but has not been widely researched. In fact, most chaos and complexity theory work in marketing has concentrated on marketing strategy, with

Diet and Sleep Physiology: Public Health and Clinical Implications

Directory of Open Access Journals (Sweden)

Sarah Frank

2017-08-01

Full Text Available This mini-review examines the complex relationship between diet and sleep and explores the clinical and public health implications of the current evidence. Dietary quality and intake of specific nutrients can impact regulatory hormonal pathways to alter sleep quantity and quality. Sleep, in turn, affects the intake of total energy, as well as of specific foods and nutrients, through biological and behavioral mechanisms. Initial research in this field focused primarily on the effects of short sleep duration on nutritional quality. However, more recent studies have explored the dynamic relationship between long sleep duration and diet. Current evidence suggests that extremes of sleep duration alter sleep patterns, hormonal levels, and circadian rhythms, which contribute to weight-related outcomes and obesity, and other risk factors for the development of chronic disease such as type 2 diabetes and cardiovascular disease. These patterns may begin as early as childhood and have impacts throughout the life course. Given that non-communicable diseases are among the leading causes of death globally, deeper understanding of the interactions between sleep and nutrition has implications for both public health and clinical practice.

Linking Supply Chain Network Complexity to Interdependence and Risk-Assessment: Scale Development and Empirical Investigation

Directory of Open Access Journals (Sweden)

Samyadip Chakraborty

2015-12-01

Full Text Available Concepts like supply chain network complexity, interdependence and risk assessment have been prominently discussed directly and indirectly in management literature over past decades and plenty of frameworks and conceptual prescriptive research works have been published contributing towards building the body of knowledge. However previous studies often lacked quantification of the findings. Consequently, the need for suitable scales becomes prominent for measuring those constructs to empirically support the conceptualized relationships. This paper expands the understanding of supply chain network complexity (SCNC and also highlights its implications on interdependence (ID between the actors and risk assessment (RAS in transaction relationships. In doing so, SCNC and RAS are operationalized to understand how SCNC affects interdependence and risk assessment between the actors in the supply chain network. The contribution of this study lies in developing and validating multi-item scales for these constructs and empirically establishing the hypothesized relationships in the Indian context based on firm data collected using survey–based questionnaire. The methodology followed included structural equation modeling. The study findings indicate that SCNC had significant relationship with interdependence, which in turn significantly affected risk assessment. This study carries both academic and managerial implications and provides an empirically supported framework linking network complexity with the two key variables (ID and RAS, playing crucial roles in managerial decision making. This study contributes to the body of knowledge and aims at guiding managers in better understanding transaction relationships.

Measuring working memory in aphasia: Comparing performance on complex span and N-back tasks

Directory of Open Access Journals (Sweden)

Maria Ivanova

2014-04-01

No significant correlations were observed between performance on complex span task and N-back tasks.Furthermore, performance on the modified listening span was related to performance on the comprehension subtest of the QASA, while no relationship was found for 2-back and 0-back tasks.Our results mirror studies in healthy controls that demonstrated no relationship between performance on the two tasks(Jaeggi et al., 2010; Kane et al., 2007. Thus although N-back tasks seem similar to traditional complex span measures and may also index abilities related to cognitive processing, the evidence to date does not warrant their direct association with the construct of WM. Implications for future investigation of cognitive deficits in aphasia will be discussed.

Exploring compassion: implications for contemporary nursing. Part 2.

Science.gov (United States)

Straughair, Collette

A range of contemporary political and professional literature endorse the principle of compassion in nursing as a core and underpinning philosophy fundamental to the profession. However, despite pledges to ensure that compassion lies at the heart of nursing, the concept has not been clearly defined. It is evident that uncovering the true meaning is complex and challenging owing to its subjective nature. In light of this, several implications must be considered. Effective student nurse recruitment is essential to ensure that the most appropriate individuals are selected. Contemporary marketing campaigns must be implemented, and recruitment strategies developed, which consider specific values and attitudes. Service user involvement in recruitment and selection, curriculum planning and learning and teaching strategies, and post-qualification education, can enhance nurses' understanding of the patient perspective and make headway in embedding compassion as a core nursing value. Additionally, effective role modelling in practice which demonstrates high-quality compassionate nursing care is essential. Nurses must be adequately supported in the clinical environment to facilitate compassionate behaviours and clinical leadership at all levels must uphold political and professional pledges to achieve this. Consideration of these implications for practice is essential to ensure that nurses are able to respond to patients with humanity and kindness, and deliver high-quality, compassionate care to all.

A Hospital Is Not Just a Factory, but a Complex Adaptive System-Implications for Perioperative Care.

Science.gov (United States)

Mahajan, Aman; Islam, Salim D; Schwartz, Michael J; Cannesson, Maxime

2017-07-01

Many methods used to improve hospital and perioperative services productivity and quality of care have assumed that the hospital is essentially a factory, and therefore, that industrial engineering and manufacturing-derived redesign approaches such as Six Sigma and Lean can be applied to hospitals and perioperative services just as they have been applied in factories. However, a hospital is not merely a factory but also a complex adaptive system (CAS). The hospital CAS has many subsystems, with perioperative care being an important one for which concepts of factory redesign are frequently advocated. In this article, we argue that applying only factory approaches such as lean methodologies or process standardization to complex systems such as perioperative care could account for difficulties and/or failures in improving performance in care delivery. Within perioperative services, only noncomplex/low-variance surgical episodes are amenable to manufacturing-based redesign. On the other hand, complex surgery/high-variance cases and preoperative segmentation (the process of distinguishing between normal and complex cases) can be viewed as CAS-like. These systems tend to self-organize, often resist or react unpredictably to attempts at control, and therefore require application of CAS principles to modify system behavior. We describe 2 examples of perioperative redesign to illustrate the concepts outlined above. These examples present complementary and contrasting cases from 2 leading delivery systems. The Mayo Clinic example illustrates the application of manufacturing-based redesign principles to a factory-like (high-volume, low-risk, and mature practice) clinical program, while the Kaiser Permanente example illustrates the application of both manufacturing-based and self-organization-based approaches to programs and processes that are not factory-like but CAS-like. In this article, we describe how factory-like processes and CAS can coexist within a hospital and how

The influence of reducing agents on the composition of technetium-99 complexes: implications for technetium-99m radiopharmaceutical preparation

International Nuclear Information System (INIS)

Baldas, J.; Bonnyman, J.; Pojer, P.M.; Williams, G.A.

1981-05-01

The use of hydrazine or formamidine sulphinic acid as reducing agents in the presence of 99 Tc-pertechnetate anion and the diethyldithiocarbamate ligand has been found to yield complexes containing Tc triple bond N and Tc=CO bonds respectively. The nitrido nitrogen atom and the carbon monoxide incorporated in these complexes as ligands originate from the reducing agents themselves. It is apparent that when reducing agents such as hydrazine or formamidine sulphinic acid are used in the preparation of Tc-99m-radiopharmaceuticals, the possibility of the formation of complexes structurally different to those obtained by use of stannous chloride must be considered

The complexities of governing in a social media world.

Science.gov (United States)

Philpott, Thomas G; Swettenham, Julie

2012-01-01

The complexity of governing has increased with the Internet's introduction of social media. Boards need to be aware of social media impact upon external stakeholder relations, as well as legal responsibilities within the organization. This paper outlines the various implications of social media that a board needs to consider. A governance framework is used to help put the issues in perspective. The conclusion is that boards need to take social media seriously and ensure that their organization has a social media risk mitigation strategy for external communications, as well as eDiscovery. Various other strategies and tactics are suggested to help boards address the challenge.

Portfolio assessment and evaluation: implications and guidelines for clinical nursing education.

Science.gov (United States)

Chabeli, M M

2002-08-01

With the advent of Outcomes-Based Education in South Africa, the quality of nursing education is debatable, especially with regard to the assessment and evaluation of clinical nursing education, which is complex and renders the validity and reliability of the methods used questionable. This paper seeks to explore and describe the use of portfolio assessment and evaluation, its implications and guidelines for its effective use in nursing education. Firstly, the concepts of assessment, evaluation, portfolio and alternative methods of evaluation are defined. Secondly, a comparison of the characteristics of the old (traditional) methods and the new alternative methods of evaluation is made. Thirdly, through deductive analysis, synthesis and inference, implications and guidelines for the effective use of portfolio assessment and evaluation are described. In view of the qualitative, descriptive and exploratory nature of the study, a focus group interview with twenty students following a post-basic degree at a university in Gauteng regarding their perceptions on the use of portfolio assessment and evaluation method in clinical nursing education was used. A descriptive method of qualitative data analysis of open coding in accordance with Tesch's protocol (in Creswell 1994:155) was used. Resultant implications and guidelines were conceptualised and described within the existing theoretical framework. Principles of trustworthiness were maintained as described by (Lincoln & Guba 1985:290-327). Ethical considerations were in accordance with DENOSA's standards of research (1998:7).

The Complexities of Adolescent Dating and Sexual Relationships: Fluidity, Meaning(s), and Implications for Young Adults' Well-Being

Science.gov (United States)

Manning, Wendy D.; Longmore, Monica A.; Copp, Jennifer; Giordano, Peggy C.

2014-01-01

The complexity of adolescents' dating and sexual lives is not easily operationalized with simple indicators of dating or sexual activity. While building on prior work that emphasizes the "risky" nature of adolescents' intimate relationships, we assess whether a variety of indicators reflecting the complexity of…

Nonlinear model of epidemic spreading in a complex social network.

Science.gov (United States)

Kosiński, Robert A; Grabowski, A

2007-10-01

The epidemic spreading in a human society is a complex process, which can be described on the basis of a nonlinear mathematical model. In such an approach the complex and hierarchical structure of social network (which has implications for the spreading of pathogens and can be treated as a complex network), can be taken into account. In our model each individual has one of the four permitted states: susceptible, infected, infective, unsusceptible or dead. This refers to the SEIR model used in epidemiology. The state of an individual changes in time, depending on the previous state and the interactions with other individuals. The description of the interpersonal contacts is based on the experimental observations of the social relations in the community. It includes spatial localization of the individuals and hierarchical structure of interpersonal interactions. Numerical simulations were performed for different types of epidemics, giving the progress of a spreading process and typical relationships (e.g. range of epidemic in time, the epidemic curve). The spreading process has a complex and spatially chaotic character. The time dependence of the number of infective individuals shows the nonlinear character of the spreading process. We investigate the influence of the preventive vaccinations on the spreading process. In particular, for a critical value of preventively vaccinated individuals the percolation threshold is observed and the epidemic is suppressed.

Nurse manager cognitive decision-making amidst stress and work complexity.

Science.gov (United States)

Shirey, Maria R; Ebright, Patricia R; McDaniel, Anna M

2013-01-01

  The present study provides insight into nurse manager cognitive decision-making amidst stress and work complexity.   Little is known about nurse manager decision-making amidst stress and work complexity. Because nurse manager decisions have the potential to impact patient care quality and safety, understanding their decision-making processes is useful for designing supportive interventions.   This qualitative descriptive study interviewed 21 nurse managers from three hospitals to answer the research question: What decision-making processes do nurse managers utilize to address stressful situations in their nurse manager role? Face-to-face interviews incorporating components of the Critical Decision Method illuminated expert-novice practice differences. Content analysis identified one major theme and three sub-themes.   The present study produced a cognitive model that guides nurse manager decision-making related to stressful situations. Experience in the role, organizational context and situation factors influenced nurse manager cognitive decision-making processes.   Study findings suggest that chronic exposure to stress and work complexity negatively affects nurse manager health and their decision-making processes potentially threatening individual, patient and organizational outcomes.   Cognitive decision-making varies based on nurse manager experience and these differences have coaching and mentoring implications. This present study contributes a current understanding of nurse manager decision-making amidst stress and work complexity. © 2012 Blackwell Publishing Ltd.

Stabilities of thiomolybdate complexes of iron; implications for retention of essential trace elements (Fe, Cu, Mo) in sulfidic waters.

Science.gov (United States)

Helz, George R; Erickson, Britt E; Vorlicek, Trent P

2014-06-01

In aquatic ecosystems, availabilities of Fe, Mo and Cu potentially limit rates of critical biological processes, including nitrogen fixation, nitrate assimilation and N2O decomposition. During long periods in Earth's history when large parts of the ocean were sulfidic, what prevented these elements' quantitative loss from marine habitats as insoluble sulfide phases? They must have been retained by formation of soluble complexes. Identities of the key ligands are poorly known but probably include thioanions. Here, the first determinations of stability constants for Fe(2+)-[MoS4](2-) complexes in aqueous solution are reported based on measurements of pyrrhotite (hexagonal FeS) solubility under mildly alkaline conditions. Two linear complexes, [FeO(OH)MoS4](3-) and [(Fe2S2)(MoS4)2](4-), best explain the observed solubility variations. Complexes that would be consistent with cuboid cluster structures were less successful, implying that such clusters probably are minor or absent in aqueous solution under the conditions studied. The new data, together with prior data on stabilities of Cu(+)-[MoS4](2-) complexes, are used to explore computationally how competition of Fe(2+) and Cu(+) for [MoS4](2-), as well as competition of [MoS4](2-) and HS(-) for both metals would be resolved in solutions representative of sulfidic natural waters. Thiomolybdate complexes will be most important at sulfide concentrations near the [MoO4](2-)-[MoS4](2-) equivalence point. At lower sulfide concentrations, thiomolybdates are insufficiently stable to be competitive ligands in natural waters and at higher sulfide concentrations HS(-) ligands out-compete thiomolybdates.

Interaction between NANOS2 and the CCR4-NOT Deadenylation Complex Is Essential for Male Germ Cell Development in Mouse

OpenAIRE

Suzuki, Atsushi; Saba, Rie; Miyoshi, Kei; Morita, Yoshinori; Saga, Yumiko

2012-01-01

Nanos is one of the evolutionarily conserved proteins implicated in germ cell development and we have previously shown that it interacts with the CCR4-NOT deadenylation complex leading to the suppression of specific RNAs. However, the molecular mechanism and physiological significance of this interaction have remained elusive. In our present study, we identify CNOT1, a component of the CCR4-NOT deadenylation complex, as a direct factor mediating the interaction with NANOS2. We find that the f...

Mapping multivalency and differential affinities within large intrinsically disordered protein complexes with segmental motion analysis.

Science.gov (United States)

Milles, Sigrid; Lemke, Edward A

2014-07-07

Intrinsically disordered proteins (IDPs) can bind to multiple interaction partners. Numerous binding regions in the IDP that act in concert through complex cooperative effects facilitate such interactions, but complicate studying IDP complexes. To address this challenge we developed a combined fluorescence correlation and time-resolved polarization spectroscopy approach to study the binding properties of the IDP nucleoporin153 (Nup153) to nuclear transport receptors (NTRs). The detection of segmental backbone mobility of Nup153 within the unperturbed complex provided a readout of local, region-specific binding properties that are usually masked in measurements of the whole IDP. The binding affinities of functionally and structurally diverse NTRs to distinct regions of Nup153 can differ by orders of magnitudes-a result with implications for the diversity of transport routes in nucleocytoplasmic transport. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tourism Diversification and Its Implications for Smart Specialisation

Directory of Open Access Journals (Sweden)

Adi Weidenfeld

2018-01-01

Full Text Available The complex nature of tourism, its strong inter-sectoral relationships and regional dimension challenge innovation. The advent of smart specialisation, which focuses on regional diversification across sectors, offers considerable and hitherto largely unrealized potential for developing innovative tourism policies within this new agenda. This paper addresses the understudied concept of tourism diversification and its unrealized relevance to smart specialisation, which has emerged as a mainstream logic underpinning EU Cohesion Policy reforms and has diffused into other OECD countries. It provides a theoretical framework for studying product, market, sectoral and regional diversification as well as related variety in tourism. Some policy implications for realizing tourism diversification and for the potential role of tourism in smart specialisation strategies in particular are suggested.

Segregation and persistence of form in the lateral occipital complex.

Science.gov (United States)

Ferber, Susanne; Humphrey, G Keith; Vilis, Tutis

2005-01-01

While the lateral occipital complex (LOC) has been shown to be implicated in object recognition, it is unclear whether this brain area is responsive to low-level stimulus-driven features or high-level representational processes. We used scrambled shape-from-motion displays to disambiguate the presence of contours from figure-ground segregation and to measure the strength of the binding process for shapes without contours. We found persisting brain activation in the LOC for scrambled displays after the motion stopped indicating that this brain area subserves and maintains figure-ground segregation processes, a low-level function in the object processing hierarchy. In our second experiment, we found that the figure-ground segregation process has some form of spatial constancy indicating top-down influences. The persisting activation after the motion stops suggests an intermediate role in object recognition processes for this brain area and might provide further evidence for the idea that the lateral occipital complex subserves mnemonic functions mediating between iconic and short-term memory.

Improvement attributes in healthcare: implications for integrated care.

Science.gov (United States)

Harnett, Patrick John

2018-04-16

Purpose Healthcare quality improvement is a key concern for policy makers, regulators, carers and service users. Despite a contemporary consensus among policy makers that integrated care represents a means to substantially improve service outcomes, progress has been slow. Difficulties achieving sustained improvement at scale imply that methods employed are not sufficient and that healthcare improvement attributes may be different when compared to prior reference domains. The purpose of this paper is to examine and synthesise key improvement attributes relevant to a complex healthcare change process, specifically integrated care. Design/methodology/approach This study is based on an integrative literature review on systemic improvement in healthcare. Findings A central theme emerging from the literature review indicates that implementing systemic change needs to address the relationship between vision, methods and participant social dynamics. Practical implications Accommodating personal and professional network dynamics is required for systemic improvement, especially among high autonomy individuals. This reinforces the need to recognise the change process as taking place in a complex adaptive system where personal/professional purpose/meaning is central to the process. Originality/value Shared personal/professional narratives are insufficiently recognised as a powerful change force, under-represented in linear and rational empirical improvement approaches.

Impact of Business Interoperability on the Performance of Complex Cooperative Supply Chain Networks: A Case Study

Directory of Open Access Journals (Sweden)

Izunildo Cabral

2018-01-01

Full Text Available This paper proposes an agent-based model for evaluating the effect of business interoperability on the performance of cooperative supply chain networks. The model is based on insights from the Industrial Marketing and Purchasing network approach and the complex systems theory perspective. To demonstrate its applicability, an explanatory case study regarding a Portuguese reverse logistics cooperative supply chain network is presented. Face-to-face interviews and forms were used to collect data. The findings show that the establishment of appropriate levels of business interoperability has helped to reduce several non-value-added interaction processes and consequently improve the operational performance of the Valorpneu network. Regarding the research implications, this paper extends the current knowledge on business interoperability and an important problem in business: how business interoperability gaps in dyadic organizational relationships affect the network of companies that the two companies belong to—network effect. In terms of practical implications, managers can use the proposed model as a starting point to simulate complex interactions between supply chain network partners and understand better how the performance of their networks emerges from these interactions and from the adoption of different levels of business interoperability.

Weighted Complex Network Analysis of Pakistan Highways

Directory of Open Access Journals (Sweden)

Yasir Tariq Mohmand

2013-01-01

Full Text Available The structure and properties of public transportation networks have great implications in urban planning, public policies, and infectious disease control. This study contributes a weighted complex network analysis of travel routes on the national highway network of Pakistan. The network is responsible for handling 75 percent of the road traffic yet is largely inadequate, poor, and unreliable. The highway network displays small world properties and is assortative in nature. Based on the betweenness centrality of the nodes, the most important cities are identified as this could help in identifying the potential congestion points in the network. Keeping in view the strategic location of Pakistan, such a study is of practical importance and could provide opportunities for policy makers to improve the performance of the highway network.

The complex interplay between neutrophils and cancer.

Science.gov (United States)

Rakic, Andrea; Beaudry, Paul; Mahoney, Douglas J

2018-03-01

Neutrophils are the most abundant type of white blood cell, and are an essential component of the innate immune system. They characteristically arrive rapidly at sites of infection and injury, and release a variety of cytokines and toxic molecules to eliminate pathogens and elicit an acute inflammatory response. Research into the function of neutrophils in cancer suggest they have divergent roles. Indeed, while most studies have found neutrophils to be associated with cancer progression, others have also documented anticancer effects. In this review, we describe the investigations into neutrophil populations that have been implicated in promoting tumor growth and metastasis as well those demonstrating antitumor functions. The collective research suggests a complex role for neutrophils in cancer biology, which raises the prospect of their targeting for the treatment of cancer.

The organization of LH2 complexes in membranes from Rhodobacter sphaeroides.

Science.gov (United States)

Olsen, John D; Tucker, Jaimey D; Timney, John A; Qian, Pu; Vassilev, Cvetelin; Hunter, C Neil

2008-11-07

The mapping of the photosynthetic membrane of Rhodobacter sphaeroides by atomic force microscopy (AFM) revealed a unique organization of arrays of dimeric reaction center-light harvesting I-PufX (RC-LH1-PufX) core complexes surrounded and interconnected by light-harvesting LH2 complexes (Bahatyrova, S., Frese, R. N., Siebert, C. A., Olsen, J. D., van der Werf, K. O., van Grondelle, R., Niederman, R. A., Bullough, P. A., Otto, C., and Hunter, C. N. (2004) Nature 430, 1058-1062). However, membrane regions consisting solely of LH2 complexes were under-represented in these images because these small, highly curved areas of membrane rendered them difficult to image even using gentle tapping mode AFM and impossible with contact mode AFM. We report AFM imaging of membranes prepared from a mutant of R. sphaeroides, DPF2G, that synthesizes only the LH2 complexes, which assembles spherical intracytoplasmic membrane vesicles of approximately 53 nm diameter in vivo. By opening these vesicles and adsorbing them onto mica to form small, LH2-only membranes for the first time. The transition from highly curved vesicle to the planar sheet is accompanied by a change in the packing of the LH2 complexes such that approximately half of the complexes are raised off the mica surface by approximately 1 nm relative to the rest. This vertical displacement produces a very regular corrugated appearance of the planar membrane sheets. Analysis of the topographs was used to measure the distances and angles between the complexes. These data are used to model the organization of LH2 complexes in the original, curved membrane. The implications of this architecture for the light harvesting function and diffusion of quinones in native membranes of R. sphaeroides are discussed.

How Project Managers Really Manage: An Indepth Look at Some Managers of Large, Complex NASA Projects

Science.gov (United States)

Mulenburg, Gerald M.; Impaeilla, Cliff (Technical Monitor)

2000-01-01

This paper reports on a research study by the author that examined ten contemporary National Aeronautics and Space Administration (NASA) complex projects. In-depth interviews with the project managers of these projects provided qualitative data about the inner workings of the project and the methodologies used in establishing and managing the projects. The inclusion of a variety of space, aeronautics, and ground based projects from several different NASA research centers helped to reduce potential bias in the findings toward any one type of project, or technical discipline. The findings address the participants and their individual approaches. The discussion includes possible implications for project managers of other large, complex, projects.

The value of electrocardiography for differential diagnosis in wide QRS complex tachycardia.

Science.gov (United States)

Sousa, Pedro A; Pereira, Salomé; Candeias, Rui; de Jesus, Ilídio

2014-03-01

Correct diagnosis in wide QRS complex tachycardia remains a challenge. Differential diagnosis between ventricular and supraventricular tachycardia has important therapeutic and prognostic implications, and although data from clinical history and physical examination may suggest a particular origin, it is the 12-lead surface electrocardiogram that usually enables this differentiation. Since 1978, various electrocardiographic criteria have been proposed for the differential diagnosis of wide complex tachycardias, particularly the presence of atrioventricular dissociation, and the axis, duration and morphology of QRS complexes. Despite the wide variety of criteria, diagnosis is still often difficult, and errors can have serious consequences. To reduce such errors, several differential diagnosis algorithms have been proposed since 1991. However, in a small percentage of wide QRS tachycardias the diagnosis remains uncertain and in these the wisest decision is to treat them as ventricular tachycardias. The authors' objective was to review the main electrocardiographic criteria and differential diagnosis algorithms of wide QRS tachycardia. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Research ethics in dissertations: ethical issues and complexity of reasoning.

Science.gov (United States)

Kjellström, S; Ross, S N; Fridlund, B

2010-07-01

Conducting ethically sound research is a fundamental principle of scientific inquiry. Recent research has indicated that ethical concerns are insufficiently dealt with in dissertations. To examine which research ethical topics were addressed and how these were presented in terms of complexity of reasoning in Swedish nurses' dissertations. Analyses of ethical content and complexity of ethical reasoning were performed on 64 Swedish nurses' PhD dissertations dated 2007. A total of seven ethical topics were identified: ethical approval (94% of the dissertations), information and informed consent (86%), confidentiality (67%), ethical aspects of methods (61%), use of ethical principles and regulations (39%), rationale for the study (20%) and fair participant selection (14%). Four of those of topics were most frequently addressed: the majority of dissertations (72%) included 3-5 issues. While many ethical concerns, by their nature, involve systematic concepts or metasystematic principles, ethical reasoning scored predominantly at lesser levels of complexity: abstract (6% of the dissertations), formal (84%) and systematic (10%). Research ethics are inadequately covered in most dissertations by nurses in Sweden. Important ethical concerns are missing, and the complexity of reasoning on ethical principles, motives and implications is insufficient. This is partly due to traditions and norms that discount ethical concerns but is probably also a reflection of the ability of PhD students and supervisors to handle complexity in general. It is suggested that the importance of ethical considerations should be emphasised in graduate and post-graduate studies and that individuals with capacity to deal with systematic and metasystematic concepts are recruited to senior research positions.

Complexity, Public Reporting, and Choice of Doctors: A Look Inside the Blackest Box of Consumer Behavior

Science.gov (United States)

Schlesinger, Mark; Kanouse, David E.; Martino, Steven C.; Shaller, Dale; Rybowski, Lise

2017-01-01

Health care consumers often make choices that are imperfectly informed and inconsistent with their expressed preferences. Past research suggests that these shortcomings become more pronounced as choices become more complex, through either additional options or more performance metrics. But it is unclear why this is true: Consumer choice remains a “black box” that research has scarcely illuminated. In this article, we identify four pathways through which complexity may impair consumer choice. We examine these pathways using data from an experiment in which consumers (hypothetically) selected a primary care physician. Some of the loss of decision quality accompanying more complex choice sets can be explained by consumers’ skills and decision-making style, but even after accounting for these factors, complexity undermines the quality of decision making in ways that cannot be fully explained. We conclude by discussing implications for report designers, sponsors, and policy makers aspiring to promote consumer empowerment and health care quality. PMID:23999489

Complexity, public reporting, and choice of doctors: a look inside the blackest box of consumer behavior.

Science.gov (United States)

Schlesinger, Mark; Kanouse, David E; Martino, Steven C; Shaller, Dale; Rybowski, Lise

2014-10-01

Health care consumers often make choices that are imperfectly informed and inconsistent with their expressed preferences. Past research suggests that these shortcomings become more pronounced as choices become more complex, through either additional options or more performance metrics. But it is unclear why this is true: Consumer choice remains a "black box" that research has scarcely illuminated. In this article, we identify four pathways through which complexity may impair consumer choice. We examine these pathways using data from an experiment in which consumers (hypothetically) selected a primary care physician. Some of the loss of decision quality accompanying more complex choice sets can be explained by consumers' skills and decision-making style, but even after accounting for these factors, complexity undermines the quality of decision making in ways that cannot be fully explained. We conclude by discussing implications for report designers, sponsors, and policy makers aspiring to promote consumer empowerment and health care quality. © The Author(s) 2013.

Complex Parts, Complex Data: Why You Need to Understand What Radiation Single Event Testing Data Does and Doesn't Show and the Implications Thereof

Science.gov (United States)

LaBel, Kenneth A.; Berg, Melanie D.

2015-01-01

Electronic parts (integrated circuits) have grown in complexity such that determining all failure modes and risks from single particle event testing is impossible. In this presentation, the authors will present why this is so and provide some realism on what this means. Its all about understanding actual risks and not making assumptions.

Pharmacokinetic drug-drug interaction and their implication in clinical management.

Science.gov (United States)

Palleria, Caterina; Di Paolo, Antonello; Giofrè, Chiara; Caglioti, Chiara; Leuzzi, Giacomo; Siniscalchi, Antonio; De Sarro, Giovambattista; Gallelli, Luca

2013-07-01

Drug-drug interactions (DDIs) are one of the commonest causes of medication error in developed countries, particularly in the elderly due to poly-therapy, with a prevalence of 20-40%. In particular, poly-therapy increases the complexity of therapeutic management and thereby the risk of clinically important DDIs, which can both induce the development of adverse drug reactions or reduce the clinical efficacy. DDIs can be classify into two main groups: pharmacokinetic and pharmacodynamic. In this review, using Medline, PubMed, Embase, Cochrane library and Reference lists we searched articles published until June 30 2012, and we described the mechanism of pharmacokinetic DDIs focusing the interest on their clinical implications.

Structure of p15PAF-PCNA complex and implications for clamp sliding during DNA replication and repair

DEFF Research Database (Denmark)

De Biasio, Alfredo; de Opakua, Alain Ibáñez; Mortuza, Gulnahar B

2015-01-01

The intrinsically disordered protein p15(PAF) regulates DNA replication and repair by binding to the proliferating cell nuclear antigen (PCNA) sliding clamp. We present the structure of the human p15(PAF)-PCNA complex. Crystallography and NMR show the central PCNA-interacting protein motif (PIP...... the DNA and facilitates the switch from replicative to translesion synthesis polymerase binding....... free and PCNA-bound p15(PAF) binds DNA mainly through its histone-like N-terminal tail, while PCNA does not, and a model of the ternary complex with DNA inside the PCNA ring is consistent with electron micrographs. We propose that p15(PAF) acts as a flexible drag that regulates PCNA sliding along...

Cyberspace as a Complex Adaptive System and the Policy and Operational Implications for Cyber Warfare

Science.gov (United States)

2014-05-22

victims would fall prey to the attack vector. Both state and non-state actors alike, driven by a combination of intrinsic and extrinsic motivations ...different roles, motivations , and intentions. Associated complexities of safeguarding cyberspace contribute to the lack of a United States (US... psychological operations. The infosphere is also the entity that DOD doctrine refers to as the information environment in which humans and automated

Environmental Restoration and Waste Management manpower needs assessment: US Department of Energy complex

Energy Technology Data Exchange (ETDEWEB)

Holmes, C.W.; Lewis, R.E.; Hunt, S.T. (Pacific Northwest Lab., Richland, WA (United States)); Finn, M.G. (Oak Ridge Associated Universities, Inc., TN (United States))

1992-06-01

A study was conducted Pacific Northwest Laboratory and Oak Ridge Associated Universities, Inc. to assess the supply and demand for 53 scientific, engineering, and technical occupations relevant to the US Department of Energy's (DOE's) Office of Environmental Restoration and Waste management (EM). These assessments were made by examining budget projections and the input of program/project and human resources managers throughout the DOE complex. Quantitative projections of full-time equivalent employees slots for each occupation have been developed for the 1993--1997 time frame. Qualitative assessments of the factors that affect recruitment, staffing, and retention are also reported. The implications of the study are discussed within the likely skills mix of the future workforce and the education and organization interventions most likely to address the needs of the DOE complex.

Epigenetics: relevance and implications for public health.

Science.gov (United States)

Rozek, Laura S; Dolinoy, Dana C; Sartor, Maureen A; Omenn, Gilbert S

2014-01-01

Improved understanding of the multilayer regulation of the human genome has led to a greater appreciation of environmental, nutritional, and epigenetic risk factors for human disease. Chromatin remodeling, histone tail modifications, and DNA methylation are dynamic epigenetic changes responsive to external stimuli. Careful interpretation can provide insights for actionable public health through collaboration between population and basic scientists and through integration of multiple data sources. We review key findings in environmental epigenetics both in human population studies and in animal models, and discuss the implications of these results for risk assessment and public health protection. To ultimately succeed in identifying epigenetic mechanisms leading to complex phenotypes and disease, researchers must integrate the various animal models, human clinical approaches, and human population approaches while paying attention to life-stage sensitivity, to generate effective prescriptions for human health evaluation and disease prevention.

Iron and zinc complexation in wild-type and ferritin-expressing wheat grain: implications for mineral transport into developing grain

DEFF Research Database (Denmark)

Neal, Andrew L; Geraki, Kalotina; Borg, Søren

2013-01-01

of modified complexation of both metals in transgenic grain overexpressing wheat ferritin. For zinc, there is a consistent doubling of the number of complexing phosphorus atoms. Although there is some EXAFS evidence for iron phytate in ferritin-expressing grain, there is also evidence of a structure lacking......We have used synchrotron-based X-ray fluorescence and absorption techniques to establish both metal distribution and complexation in mature wheat grains. In planta, extended X-ray absorption fine structure (EXAFS) spectroscopy reveals iron phytate and zinc phytate structures in aleurone cells...... of ferritin-expressing grains is quite different from that in wild-type grain. This may explain why the raised levels of minerals transported to the developing grain accumulate within the crease region of the transgenic grain....

Biological significance of complex N-glycans in plants and their impact on plant physiology.

Science.gov (United States)

Strasser, Richard

2014-01-01

Asparagine (N)-linked protein glycosylation is a ubiquitous co- and post-translational modification which can alter the biological function of proteins and consequently affects the development, growth, and physiology of organisms. Despite an increasing knowledge of N-glycan biosynthesis and processing, we still understand very little about the biological function of individual N-glycan structures in plants. In particular, the N-glycan-processing steps mediated by Golgi-resident enzymes create a structurally diverse set of protein-linked carbohydrate structures. Some of these complex N-glycan modifications like the presence of β1,2-xylose, core α1,3-fucose or the Lewis a-epitope are characteristic for plants and are evolutionary highly conserved. In mammals, complex N-glycans are involved in different cellular processes including molecular recognition and signaling events. In contrast, the complex N-glycan function is still largely unknown in plants. Here, in this short review, I focus on important recent developments and discuss their implications for future research in plant glycobiology and plant biotechnology.

The sodium pentothal hypnosis interview with follow-up treatment for complex regional pain syndrome.

Science.gov (United States)

Simon, E P; Dahl, L F

1999-08-01

A patient who was unresponsive to multiple conservative medical treatments for complex regional pain syndrome was assessed using a novel approach--the sodium pentothal hypnosis interview. The interview suggested that his pain was centrally generated. The patient's pain symptoms resolved with hypnotherapeutic treatment. Indications for this procedure and implications for assessment and treatment are discussed. This case raises more questions than it answers, and leaves the reader to struggle with current difficulties in diagnostic decision-making.

GABBR1 has a HERV-W LTR in its regulatory region – a possible implication for schizophrenia

Directory of Open Access Journals (Sweden)

Hegyi Hedi

2013-02-01

Full Text Available Abstract Schizophrenia is a complex disease with uncertain aetiology. We suggest GABBR1, GABA receptor B1 implicated in schizophrenia based on a HERV-W LTR in the regulatory region of GABBR1. Our hypothesis is supported by: (i GABBR1 is in the 6p22 genomic region most often implicated in schizophrenia; (ii microarray studies found that only presynaptic pathway-related genes, including GABA receptors, have altered expression in schizophrenic patients and (iii it explains how HERV-W elements, expressed in schizophrenia, play a role in the disease: by altering the expression of GABBR1 via a long terminal repeat that is also a regulatory element to GABBR1. Reviewers This paper was reviewed by Sandor Pongor and Martijn Huynen.

Circulating growth hormone (GH)-binding protein complex: a major constituent of plasma GH in man

International Nuclear Information System (INIS)

Baumann, G.; Amburn, K.; Shaw, M.A.

1988-01-01

The recent discovery of a specific binding protein for human GH (hGH) in human plasma suggests that hGH circulates in part as a complex in association with the binding protein(s). However, the magnitude of the complexed fraction prevailing under physiological conditions is unknown because of 1) dissociation of the complex during analysis and 2) potential differences in the binding characteristics of radiolabeled and native hGH. We conducted experiments designed to minimize dissociation during analysis (gel filtration in prelabeled columns, frontal analysis, and batch molecular sieving) with both native and radioiodinated hGH. All three methods yielded similar estimates for the complexed fraction. In normal plasma the bound fraction for 22 K hGH averaged 50.1% (range, 39-59%), that for 20 K hGH averaged 28.5% (range, 26-31%). Above a hGH level of about 20 ng/ml the bound fraction declines in concentration-dependent manner due to saturation of the binding protein. We conclude that a substantial part of circulating hGH is complexed with carrier proteins. This concept has important implications for the metabolism, distribution, and biological activity of hGH

Ventriculoperitoneal shunt-related infections caused by Staphylococcus epidermidis: pathogenesis and implications for treatment.

LENUS (Irish Health Repository)

Stevens, Niall T

2012-12-01

The insertion of medical devices, such as intraventricular shunts, is often complicated by infection leading to ventriculitis. Frequently, such infections result from colonisation and subsequent biofilm formation on the surfaces of the shunts by Staphylococcus epidermidis. The pathogenesis of neurosurgical shunt-related infection is complex with interactions between the pathogen, the device and the unique local immunological environment of the central nervous system (CNS). An ability to form biofilm, the main virulence determinant of Staphylococcus epidermidis, facilitates protection of the organism from the host defences while still initiating an immunological response. The presence of the blood brain barrier (BBB) and the biofilm itself also complicates treatment, which presents many challenges when managing shunt infections. A greater understanding of the interplay between S. epidermidis and the CNS could potentially improve the diagnosis, treatment and management of such infections. This review describes the pathogenesis, treatment and implications of S. epidermidis ventriculoperitoneal shunt-related infections, concentrating on recent research and the implications for treatment.

Cognitive complexity of the medical record is a risk factor for major adverse events.

Science.gov (United States)

Roberson, David; Connell, Michael; Dillis, Shay; Gauvreau, Kimberlee; Gore, Rebecca; Heagerty, Elaina; Jenkins, Kathy; Ma, Lin; Maurer, Amy; Stephenson, Jessica; Schwartz, Margot

2014-01-01

Patients in tertiary care hospitals are more complex than in the past, but the implications of this are poorly understood as "patient complexity" has been difficult to quantify. We developed a tool, the Complexity Ruler, to quantify the amount of data (as bits) in the patient’s medical record. We designated the amount of data in the medical record as the cognitive complexity of the medical record (CCMR). We hypothesized that CCMR is a useful surrogate for true patient complexity and that higher CCMR correlates with risk of major adverse events. The Complexity Ruler was validated by comparing the measured CCMR with physician rankings of patient complexity on specific inpatient services. It was tested in a case-control model of all patients with major adverse events at a tertiary care pediatric hospital from 2005 to 2006. The main outcome measure was an externally reported major adverse event. We measured CCMR for 24 hours before the event, and we estimated lifetime CCMR. Above empirically derived cutoffs, 24-hour and lifetime CCMR were risk factors for major adverse events (odds ratios, 5.3 and 6.5, respectively). In a multivariate analysis, CCMR alone was essentially as predictive of risk as a model that started with 30-plus clinical factors. CCMR correlates with physician assessment of complexity and risk of adverse events. We hypothesize that increased CCMR increases the risk of physician cognitive overload. An automated version of the Complexity Ruler could allow identification of at-risk patients in real time.

A novel dimeric inhibitor targeting Beta2GPI in Beta2GPI/antibody complexes implicated in antiphospholipid syndrome.

Directory of Open Access Journals (Sweden)

Alexey Kolyada

2010-12-01

Full Text Available β2GPI is a major antigen for autoantibodies associated with antiphospholipid syndrome (APS, an autoimmune disease characterized by thrombosis and recurrent pregnancy loss. Only the dimeric form of β2GPI generated by anti-β2GPI antibodies is pathologically important, in contrast to monomeric β2GPI which is abundant in plasma.We created a dimeric inhibitor, A1-A1, to selectively target β2GPI in β2GPI/antibody complexes. To make this inhibitor, we isolated the first ligand-binding module from ApoER2 (A1 and connected two A1 modules with a flexible linker. A1-A1 interferes with two pathologically important interactions in APS, the binding of β2GPI/antibody complexes with anionic phospholipids and ApoER2. We compared the efficiency of A1-A1 to monomeric A1 for inhibition of the binding of β2GPI/antibody complexes to anionic phospholipids. We tested the inhibition of β2GPI present in human serum, β2GPI purified from human plasma and the individual domain V of β2GPI. We demonstrated that when β2GPI/antibody complexes are formed, A1-A1 is much more effective than A1 in inhibition of the binding of β2GPI to cardiolipin, regardless of the source of β2GPI. Similarly, A1-A1 strongly inhibits the binding of dimerized domain V of β2GPI to cardiolipin compared to the monomeric A1 inhibitor. In the absence of anti-β2GPI antibodies, both A1-A1 and A1 only weakly inhibit the binding of pathologically inactive monomeric β2GPI to cardiolipin.Our results suggest that the approach of using a dimeric inhibitor to block β2GPI in the pathological multivalent β2GPI/antibody complexes holds significant promise. The novel inhibitor A1-A1 may be a starting point in the development of an effective therapeutic for antiphospholipid syndrome.

A Novel Dimeric Inhibitor Targeting Beta2GPI in Beta2GPI/Antibody Complexes Implicated in Antiphospholipid Syndrome

Energy Technology Data Exchange (ETDEWEB)

A Kolyada; C Lee; A De Biasio; N Beglova

2011-12-31

{beta}2GPI is a major antigen for autoantibodies associated with antiphospholipid syndrome (APS), an autoimmune disease characterized by thrombosis and recurrent pregnancy loss. Only the dimeric form of {beta}2GPI generated by anti-{beta}2GPI antibodies is pathologically important, in contrast to monomeric {beta}2GPI which is abundant in plasma. We created a dimeric inhibitor, A1-A1, to selectively target {beta}2GPI in {beta}2GPI/antibody complexes. To make this inhibitor, we isolated the first ligand-binding module from ApoER2 (A1) and connected two A1 modules with a flexible linker. A1-A1 interferes with two pathologically important interactions in APS, the binding of {beta}2GPI/antibody complexes with anionic phospholipids and ApoER2. We compared the efficiency of A1-A1 to monomeric A1 for inhibition of the binding of {beta}2GPI/antibody complexes to anionic phospholipids. We tested the inhibition of {beta}2GPI present in human serum, {beta}2GPI purified from human plasma and the individual domain V of {beta}2GPI. We demonstrated that when {beta}2GPI/antibody complexes are formed, A1-A1 is much more effective than A1 in inhibition of the binding of {beta}2GPI to cardiolipin, regardless of the source of {beta}2GPI. Similarly, A1-A1 strongly inhibits the binding of dimerized domain V of {beta}2GPI to cardiolipin compared to the monomeric A1 inhibitor. In the absence of anti-{beta}2GPI antibodies, both A1-A1 and A1 only weakly inhibit the binding of pathologically inactive monomeric {beta}2GPI to cardiolipin. Our results suggest that the approach of using a dimeric inhibitor to block {beta}2GPI in the pathological multivalent {beta}2GPI/antibody complexes holds significant promise. The novel inhibitor A1-A1 may be a starting point in the development of an effective therapeutic for antiphospholipid syndrome.

Cognitive implications of facilitating echoic persistence.

Science.gov (United States)

Baldwin, Carryl L

2007-06-01

Seventeen participants performed a tone-pattern-matching task at different presentation levels while concurrently engaged in a simulated-driving task. Presentation levels of 60, 65, and 70 dBC (SPL) were combined factorially with tone-matching delays of 2, 3, and 4 sec. Intensity had no effect on performance in single-task conditions and short-delay conditions. However, when the participants were engaged concurrently in the driving task, a significant interaction between presentation level and delay was observed. In the longest delay condition, the participants performed the tone-pattern-matching task more efficiently (more quickly and without additional errors) as presentation intensity increased. These findings demonstrate the interaction between sensory and cognitive processes and point to a direct-intensity relationship where intensity affects the persistence of echoic memory. Implications for facilitating auditory processing and improving auditory interfaces in complex systems (i.e., transportation environments), particularly for older and hearing-impaired listeners, are discussed.

The vomeronasal complex of nocturnal strepsirhines and implications for the ancestral condition in primates.

Science.gov (United States)

Garrett, Eva C; Dennis, John C; Bhatnagar, Kunwar P; Durham, Emily L; Burrows, Anne M; Bonar, Christopher J; Steckler, Natalie K; Morrison, Edward E; Smith, Timothy D

2013-12-01

This study investigates the vomeronasal organ in extant nocturnal strepsirhines as a model for ancestral primates. Cadaveric samples from 10 strepsirhine species, ranging from fetal to adult ages, were studied histologically. Dimensions of structures in the vomeronasal complex, such as the vomeronasal neuroepithelium (VNNE) and vomeronasal cartilage (VNC) were measured in serial sections and selected specimens were studied immunohistochemically to determine physiological aspects of the vomeronasal sensory neurons (VSNs). Osteological features corresponding to vomeronasal structures were studied histologically and related to 3-D CT reconstructions. The VNC consistently rests in a depression on the palatal portion of the maxilla, which we refer to as the vomeronasal groove (VNG). Most age comparisons indicate that in adults VNNE is about twice the length compared with perinatal animals. In VNNE volume, adults are 2- to 3-fold larger compared with perinatal specimens. Across ages, a strong linear relationship exists between VNNE dimensions and body length, mass, and midfacial length. Results indicate that the VNNE of nocturnal strepsirhines is neurogenic postnatally based on GAP43 expression. In addition, based on Olfactory Marker Protein expression, terminally differentiated VSNs are present in the VNNE. Therefore, nocturnal strepsirhines have basic similarities to rodents in growth and maturational characteristics of VSNs. These results indicate that a functional vomeronasal system is likely present in all nocturnal strepsirhines. Finally, given that osteological features such as the VNG are visible on midfacial bones, primate fossils can be assessed to determine whether primate ancestors possessed a vomeronasal complex morphologically similar to that of modern nocturnal strepsirhines. Copyright © 2013 Wiley Periodicals, Inc.

PICs in the injector complex - what are we talking about?

International Nuclear Information System (INIS)

Hanke, K

2014-01-01

This presentation will identify PIC activities for the LHC injector chain, and point out borderline cases to pure consolidation and upgrade. The most important PIC items will be listed for each LIU project (PSB, PS, SPS) and categorized by a) the risk if not performed and b) the implications of doing them. This will in particular address the consequences on performance, schedule, reliability, commissioning time, operational complexity etc. The additional cost of PICs with regard to pure consolidation will be estimated and possible time lines for the implementation of the PICs will be discussed. In this context, it will be evaluated if the PICs can be implemented over several machine stops

Toward the adoption of complexity science in health care: implications for risk-taking and decision-making activities.

Science.gov (United States)

Perez, Bianca; Liberman, Aaron

2011-01-01

This article explores the issues of risk taking and decision making in health care. An analysis of various sociocultural and psychological influences is provided for understanding of the dominant mind set in this industry. In tandem with this analysis, the evolution of system theories is described so as to promote understanding of the relative merits of the mechanistic and complexity philosophies. These philosophies are at odds with each other, conceptually and practically speaking; however, it seems that the complexity approach offers more promising strategies for the growth and development of health care. Recommendations for improving employee competencies and the organizational structure and culture in health care are offered in light of this analysis. These recommendations are relevant to activities that are clinical and administrative in nature.

Geomorphology and landscape organization of a northern peatland complex

Science.gov (United States)

Richardson, M. C.

2012-12-01

The geomorphic evolution of northern peatlands is governed by complex ecohydrological feedback mechanisms and associated hydro-climatic drivers. For example, prevailing models of bog development (i.e. Ingram's groundwater mounding hypothesis and variants) attempt to explicitly link bog dome characteristics to the regional climate based on analytical and numerical models of lateral groundwater flow and the first-order control of water table position on rates of peat accumulation. In this talk I will present new results from quantitative geomorphic analyses of a northern peatland complex at the De Beers Victor diamond mine site in the Hudson Bay Lowlands of northern Ontario. This work capitalizes on spatially-extensive, high-resolution topographic (LiDAR) data to rigorously test analytical and numerical models of bog dome development in this landscape. The analysis and discussion are then expanded beyond individual bog formations to more broadly consider ecohydrological drivers of landscape organization, with implications for understanding and modeling catchment-scale runoff response. Results show that in this landscape, drainage patterns exhibit relatively well-organized characteristics consistent with observed runoff responses in six gauged research catchments. Interpreted together, the results of these geomorphic and hydrologic analyses help refine our understanding of water balance partitioning among different landcover types within northern peatland complexes. These findings can be used to help guide the development of appropriate numerical model structures for hydrologic prediction in ungauged peatland basins of northern Canada.

Implications of immune dysfunction on endometriosis associated infertility.

Science.gov (United States)

Miller, Jessica E; Ahn, Soo Hyun; Monsanto, Stephany P; Khalaj, Kasra; Koti, Madhuri; Tayade, Chandrakant

2017-01-24

Endometriosis is a complex, inflammatory disease that affects 6-10% of reproductive-aged women. Almost half of the women with endometriosis experience infertility. Despite the excessive prevalence, the pathogenesis of endometriosis and its associated infertility is unknown and a cure is not available. While many theories have been suggested to link endometriosis and infertility, a consensus among investigators has not emerged. In this extensive review of the literature as well as research from our laboratory, we provide potential insights into the role of immune dysfunction in endometriosis associated infertility. We discuss the implication of the peritoneal inflammatory microenvironment on various factors that contribute to infertility such as hormonal imbalance, oxidative stress and how these could further lead to poor oocyte, sperm and embryo quality, impaired receptivity of the endometrium and implantation failure.

Single-molecule force-conductance spectroscopy of hydrogen-bonded complexes

Science.gov (United States)

Pirrotta, Alessandro; De Vico, Luca; Solomon, Gemma C.; Franco, Ignacio

2017-03-01

The emerging ability to study physical properties at the single-molecule limit highlights the disparity between what is observable in an ensemble of molecules and the heterogeneous contributions of its constituent parts. A particularly convenient platform for single-molecule studies are molecular junctions where forces and voltages can be applied to individual molecules, giving access to a series of electromechanical observables that can form the basis of highly discriminating multidimensional single-molecule spectroscopies. Here, we computationally examine the ability of force and conductance to inform about molecular recognition events at the single-molecule limit. For this, we consider the force-conductance characteristics of a prototypical class of hydrogen bonded bimolecular complexes sandwiched between gold electrodes. The complexes consist of derivatives of a barbituric acid and a Hamilton receptor that can form up to six simultaneous hydrogen bonds. The simulations combine classical molecular dynamics of the mechanical deformation of the junction with non-equilibrium Green's function computations of the electronic transport. As shown, in these complexes hydrogen bonds mediate transport either by directly participating as a possible transport pathway or by stabilizing molecular conformations with enhanced conductance properties. Further, we observe that force-conductance correlations can be very sensitive to small changes in the chemical structure of the complexes and provide detailed information about the behavior of single molecules that cannot be gleaned from either measurement alone. In fact, there are regions during the elongation that are only mechanically active, others that are only conductance active, and regions where both force and conductance changes as the complex is mechanically manipulated. The implication is that force and conductance provide complementary information about the evolution of molecules in junctions that can be used to

Rad50S alleles of the Mre11 complex: questions answered and questions raised.

Science.gov (United States)

Usui, Takehiko; Petrini, John H J; Morales, Monica

2006-08-15

We find that Rad50S mutations in yeast and mammals exhibit constitutive PIKK (PI3-kinase like kinase)-dependent signaling [T. Usui, H. Ogawa, J.H. Petrini, A DNA damage response pathway controlled by Tel1 and the Mre11 complex. Mol. Cell 7 (2001) 1255-1266.; M. Morales, J.W. Theunissen, C.F. Kim, R. Kitagawa, M.B. Kastan, J.H. Petrini, The Rad50S allele promotes ATM-dependent DNA damage responses and suppresses ATM deficiency: implications for the Mre11 complex as a DNA damage sensor. Genes Dev. 19 (2005) 3043-4354.]. The signaling depends on Mre11 complex functions, consistent with its role as a DNA damage sensor. Rad50S is distinct from hypomorphic mutations of Mre11 and Nbs1 in mammals [M. Morales, J.W. Theunissen, C.F. Kim, R. Kitagawa, M.B. Kastan, J.H. Petrini, The Rad50S allele promotes ATM-dependent DNA damage responses and suppresses ATM deficiency: implications for the Mre11 complex as a DNA damage sensor. Genes Dev. 19 (2005) 3043-3054.; J.P. Carney, R.S. Maser, H. Olivares, E.M. Davis, Le M. Beau, J.R. Yates, III, L. Hays, W.F. Morgan, J.H. Petrini, The hMre11/hRad50 protein complex and Nijmegen breakage syndrome: linkage of double-strand break repair to the cellular DNA damage response. Cell 93 (1998) 477-486.; G.S. Stewart, R.S. Maser, T. Stankovic, D.A. Bressan, M.I. Kaplan, N.G. Jaspers, A. Raams, P.J. Byrd, J.H. Petrini, A.M. Taylor, The DNA double-strand break repair gene hMRE11 is mutated in individuals with an ataxia-telangiectasia-like disorder. Cell 99 (1999) 577-587.; B.R. Williams, O.K. Mirzoeva, W.F. Morgan, J. Lin, W. Dunnick, J.H. Petrini, A murine model of nijmegen breakage syndrome. Curr. Biol. 12 (2002) 648-653.; J.W. Theunissen, M.I. Kaplan, P.A. Hunt, B.R. Williams, D.O. Ferguson, F.W. Alt, J.H. Petrini, Checkpoint failure and chromosomal instability without lymphomagenesis in Mre11(ATLD1/ATLD1) mice. Mol. Cell 12 (2003) 1511-1523.] and the Mre11 complex deficiency in yeast [T. Usui, H. Ogawa, J.H. Petrini, A DNA damage response

Cross-modal links among vision, audition, and touch in complex environments.

Science.gov (United States)

Ferris, Thomas K; Sarter, Nadine B

2008-02-01

This study sought to determine whether performance effects of cross-modal spatial links that were observed in earlier laboratory studies scale to more complex environments and need to be considered in multimodal interface design. It also revisits the unresolved issue of cross-modal cuing asymmetries. Previous laboratory studies employing simple cues, tasks, and/or targets have demonstrated that the efficiency of processing visual, auditory, and tactile stimuli is affected by the modality, lateralization, and timing of surrounding cues. Very few studies have investigated these cross-modal constraints in the context of more complex environments to determine whether they scale and how complexity affects the nature of cross-modal cuing asymmetries. Amicroworld simulation of battlefield operations with a complex task set and meaningful visual, auditory, and tactile stimuli was used to investigate cuing effects for all cross-modal pairings. Significant asymmetric performance effects of cross-modal spatial links were observed. Auditory cues shortened response latencies for collocated visual targets but visual cues did not do the same for collocated auditory targets. Responses to contralateral (rather than ipsilateral) targets were faster for tactually cued auditory targets and each visual-tactile cue-target combination, suggesting an inhibition-of-return effect. The spatial relationships between multimodal cues and targets significantly affect target response times in complex environments. The performance effects of cross-modal links and the observed cross-modal cuing asymmetries need to be examined in more detail and considered in future interface design. The findings from this study have implications for the design of multimodal and adaptive interfaces and for supporting attention management in complex, data-rich domains.

A systematic review on the neural effects of music on emotion regulation: implications for music therapy practice.

Science.gov (United States)

Moore, Kimberly Sena

2013-01-01

Emotion regulation (ER) is an internal process through which a person maintains a comfortable state of arousal by modulating one or more aspects of emotion. The neural correlates underlying ER suggest an interplay between cognitive control areas and areas involved in emotional reactivity. Although some studies have suggested that music may be a useful tool in ER, few studies have examined the links between music perception/production and the neural mechanisms that underlie ER and resulting implications for clinical music therapy treatment. Objectives of this systematic review were to explore and synthesize what is known about how music and music experiences impact neural structures implicated in ER, and to consider clinical implications of these findings for structuring music stimuli to facilitate ER. A comprehensive electronic database search resulted in 50 studies that met predetermined inclusion and exclusion criteria. Pertinent data related to the objective were extracted and study outcomes were analyzed and compared for trends and common findings. Results indicated there are certain music characteristics and experiences that produce desired and undesired neural activation patterns implicated in ER. Desired activation patterns occurred when listening to preferred and familiar music, when singing, and (in musicians) when improvising; undesired activation patterns arose when introducing complexity, dissonance, and unexpected musical events. Furthermore, the connection between music-influenced changes in attention and its link to ER was explored. Implications for music therapy practice are discussed and preliminary guidelines for how to use music to facilitate ER are shared.

Ethylene Regulates Levels of Ethylene Receptor/CTR1 Signaling Complexes in Arabidopsis thaliana*

Science.gov (United States)

Shakeel, Samina N.; Gao, Zhiyong; Amir, Madiha; Chen, Yi-Feng; Rai, Muneeza Iqbal; Haq, Noor Ul; Schaller, G. Eric

2015-01-01

The plant hormone ethylene is perceived by a five-member family of receptors in Arabidopsis thaliana. The receptors function in conjunction with the Raf-like kinase CTR1 to negatively regulate ethylene signal transduction. CTR1 interacts with multiple members of the receptor family based on co-purification analysis, interacting more strongly with receptors containing a receiver domain. Levels of membrane-associated CTR1 vary in response to ethylene, doing so in a post-transcriptional manner that correlates with ethylene-mediated changes in levels of the ethylene receptors ERS1, ERS2, EIN4, and ETR2. Interactions between CTR1 and the receptor ETR1 protect ETR1 from ethylene-induced turnover. Kinetic and dose-response analyses support a model in which two opposing factors control levels of the ethylene receptor/CTR1 complexes. Ethylene stimulates the production of new complexes largely through transcriptional induction of the receptors. However, ethylene also induces turnover of receptors, such that levels of ethylene receptor/CTR1 complexes decrease at higher ethylene concentrations. Implications of this model for ethylene signaling are discussed. PMID:25814663

Mining TCGA data using Boolean implications.

Directory of Open Access Journals (Sweden)

Subarna Sinha

Full Text Available Boolean implications (if-then rules provide a conceptually simple, uniform and highly scalable way to find associations between pairs of random variables. In this paper, we propose to use Boolean implications to find relationships between variables of different data types (mutation, copy number alteration, DNA methylation and gene expression from the glioblastoma (GBM and ovarian serous cystadenoma (OV data sets from The Cancer Genome Atlas (TCGA. We find hundreds of thousands of Boolean implications from these data sets. A direct comparison of the relationships found by Boolean implications and those found by commonly used methods for mining associations show that existing methods would miss relationships found by Boolean implications. Furthermore, many relationships exposed by Boolean implications reflect important aspects of cancer biology. Examples of our findings include cis relationships between copy number alteration, DNA methylation and expression of genes, a new hierarchy of mutations and recurrent copy number alterations, loss-of-heterozygosity of well-known tumor suppressors, and the hypermethylation phenotype associated with IDH1 mutations in GBM. The Boolean implication results used in the paper can be accessed at http://crookneck.stanford.edu/microarray/TCGANetworks/.

RECQ HELICASE RECQL4 PARTICIPATES IN NON-HOMOLOGOUS END JOINING AND INTERACTS WITH THE KU COMPLEX

DEFF Research Database (Denmark)

Shamanna, Raghavendra A; Singh, Dharmendra Kumar; Lu, Huiming

2014-01-01

-irradiation and resulted in accumulation of 53BP1 foci after irradiation, indicating defects in the processing of DSB. We find that RECQL4 interacts with the Ku70/Ku80 heterodimer, part of the DNA-dependent protein kinase (DNA-PK) complex, via its N-terminal domain. Further, RECQL4 stimulates higher order DNA binding...... of Ku70/Ku80 to a blunt end DNA substrate. Taken together, these results implicate that RECQL4 participates in the NHEJ pathway of DSB repair via a functional interaction with the Ku70/Ku80 complex. This is the first study to provide both in vitro and in vivo evidence for a role of a RecQ helicase...

A muscle-specific knockout implicates nuclear receptor coactivator MED1 in the regulation of glucose and energy metabolism.

Science.gov (United States)

Chen, Wei; Zhang, Xiaoting; Birsoy, Kivanc; Roeder, Robert G

2010-06-01

As conventional transcriptional factors that are activated in diverse signaling pathways, nuclear receptors play important roles in many physiological processes that include energy homeostasis. The MED1 subunit of the Mediator coactivator complex plays a broad role in nuclear receptor-mediated transcription by anchoring the Mediator complex to diverse promoter-bound nuclear receptors. Given the significant role of skeletal muscle, in part through the action of nuclear receptors, in glucose and fatty acid metabolism, we generated skeletal muscle-specific Med1 knockout mice. Importantly, these mice show enhanced insulin sensitivity and improved glucose tolerance as well as resistance to high-fat diet-induced obesity. Furthermore, the white muscle of these mice exhibits increased mitochondrial density and expression of genes specific to type I and type IIA fibers, indicating a fast-to-slow fiber switch, as well as markedly increased expression of the brown adipose tissue-specific UCP-1 and Cidea genes that are involved in respiratory uncoupling. These dramatic results implicate MED1 as a powerful suppressor in skeletal muscle of genetic programs implicated in energy expenditure and raise the significant possibility of therapeutical approaches for metabolic syndromes and muscle diseases through modulation of MED1-nuclear receptor interactions.

Unraveling the Complexity of the Jevons Paradox: The Link Between Innovation, Efficiency, and Sustainability

Directory of Open Access Journals (Sweden)

Mario Giampietro

2018-04-01

Full Text Available The term “Jevons Paradox” flags the need to consider the different hierarchical scales at which a system under analysis changes its identity in response to an innovation. Accordingly, an analysis of the implications of the Jevons Paradox must abandon the realm of reductionism and deal with the complexity inherent in the issue of sustainability: when studying evolution and real change how can we define “what has to be sustained” in a system that continuously becomes something else? In an attempt to address this question this paper presents three theoretical concepts foreign to conventional scientific analysis: (i complex adaptive systems—to address the peculiar characteristics of learning and self-producing systems; (ii holons and holarchy—to explain the implications of the ambiguity found when observing the relation between functional and structural elements across different scales (steady-state vs. evolution; and (iii Holling's adaptive cycle—to illustrate the existence of different phases in the evolutionary trajectory of a complex adaptive system interacting with its context in which either external or internal constraints can become limiting. These concepts are used to explain systemic drivers of the Jevons Paradox. Looking at society's thermodynamic foundations, sustainability is based on a dynamic balance of two contrasting principles regulating the evolution of complex adaptive systems: the minimum entropy production and the maximum energy flux. The co-existence of these two principles explains why in different situations innovation has to play a different role in the “sustainable development” of society: (i when society is not subject to external biophysical constraints improvements in efficiency serve to increase the final consumption of society and expand its diversity of functions and structures; (ii when the expansion of society is limited by external constraints improvements in efficiency should be used to avoid as

Hyperoxia decreases glycolytic capacity, glycolytic reserve and oxidative phosphorylation in MLE-12 cells and inhibits complex I and II function, but not complex IV in isolated mouse lung mitochondria.

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Kumuda C Das

Full Text Available High levels of oxygen (hyperoxia are frequently used in critical care units and in conditions of respiratory insufficiencies in adults, as well as in infants. However, hyperoxia has been implicated in a number of pulmonary disorders including bronchopulmonary dysplasia (BPD and adult respiratory distress syndrome (ARDS. Hyperoxia increases the generation of reactive oxygen species (ROS in the mitochondria that could impair the function of the mitochondrial electron transport chain. We analyzed lung mitochondrial function in hyperoxia using the XF24 analyzer (extracellular flux and optimized the assay for lung epithelial cells and mitochondria isolated from lungs of mice. Our data show that hyperoxia decreases basal oxygen consumption rate (OCR, spare respiratory capacity, maximal respiration and ATP turnover in MLE-12 cells. There was significant decrease in glycolytic capacity and glycolytic reserve in MLE-12 cells exposed to hyperoxia. Using mitochondria isolated from lungs of mice exposed to hyperoxia or normoxia we have shown that hyperoxia decreased the basal, state 3 and state3 μ (respiration in an uncoupled state respirations. Further, using substrate or inhibitor of a specific complex we show that the OCR via complex I and II, but not complex IV was decreased, demonstrating that complexes I and II are specific targets of hyperoxia. Further, the activities of complex I (NADH dehydrogenase, NADH-DH and complex II (succinate dehydrogenase, SDH were decreased in hyperoxia, but the activity of complex IV (cytochrome oxidase, COX remains unchanged. Taken together, our study show that hyperoxia impairs glycolytic and mitochondrial energy metabolism in in tact cells, as well as in lungs of mice by selectively inactivating components of electron transport system.

Parameters in dynamic models of complex traits are containers of missing heritability.

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Yunpeng Wang

Full Text Available Polymorphisms identified in genome-wide association studies of human traits rarely explain more than a small proportion of the heritable variation, and improving this situation within the current paradigm appears daunting. Given a well-validated dynamic model of a complex physiological trait, a substantial part of the underlying genetic variation must manifest as variation in model parameters. These parameters are themselves phenotypic traits. By linking whole-cell phenotypic variation to genetic variation in a computational model of a single heart cell, incorporating genotype-to-parameter maps, we show that genome-wide association studies on parameters reveal much more genetic variation than when using higher-level cellular phenotypes. The results suggest that letting such studies be guided by computational physiology may facilitate a causal understanding of the genotype-to-phenotype map of complex traits, with strong implications for the development of phenomics technology.

Stratigraphic units overlying the Zambales Ophiolite Complex (ZOC) in Luzon, (Philippines): Tectonostratigraphic significance and regional implications

Science.gov (United States)

Queaño, Karlo L.; Dimalanta, Carla B.; Yumul, Graciano P.; Marquez, Edanjarlo J.; Faustino-Eslava, Decibel V.; Suzuki, Shigeyuki; Ishida, Keisuke

2017-07-01

The Zambales Ophiolite Complex (ZOC) on the island of Luzon, Philippines is one of the most well-studied crust-mantle sequences in the region. Several massifs comprise the ZOC, one of which is the Coto Block overlain by clastic sedimentary units previously dated as Eocene. Geochronologic studies from diabase, granodiorites and other late-stage magmatic products similarly yielded the same age. Succeeding tectonic models have therefore all been grounded on the assumption that the entire ZOC is Eocene. Recent investigations, however, revealed the presence of chert blocks within the Early to Middle Miocene clastic formation overlying the Acoje Block in the northern part of the ophiolite complex. Radiolarians extracted from the cherts yielded a stratigraphic range that suggests a Late Jurassic to Early Cretaceous age. The recognition of a much older age than previously reported of the ZOC warrants a re-examination of its actual distribution and genesis. Correlating with other similarly-aged ophiolites, we suggest defining a western Mesozoic ophiolite belt, largely extending from the west-central portion of the archipelago to the northeastern tip of Luzon island. Tentatively, we attribute the Mesozoic ophiolitic and associated rocks in western Luzon to an arc-continent collision involving the Philippine Mobile Belt and the Palawan Microcontinental Block. In addition, differences in the clastic compositions of the Cenozoic sedimentary formations provide material not only for deciphering the ZOC's unroofing history but also for constraining the timing of province linkage. The intermittent appearance of lithic fragments and detrital minerals from the ophiolite in the units of the Middle Miocene Candelaria Limestone and the Late Miocene to Early Pliocene Sta. Cruz Formation indicates significant but geographically variable contributions from the ophiolite complex. In the northern Zambales Range, the Sta. Cruz Formation caps the Coto Block and the Acoje Block of the ZOC

Defects in the COG complex and COG-related trafficking regulators affect neuronal Golgi function.

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Leslie K Climer

2015-10-01

Full Text Available The Conserved Oligomeric Golgi (COG complex is an evolutionarily conserved hetero-octameric protein complex that has been proposed to organize vesicle tethering at the Golgi apparatus. Defects in seven of the eight COG subunits are linked to Congenital Disorders of Glycosylation (CDG-type II, a family of rare diseases involving misregulation of protein glycosylation, alterations in Golgi structure, variations in retrograde trafficking through the Golgi and system-wide clinical pathologies. A troublesome aspect of these diseases are the neurological pathologies such as low IQ, microcephaly and cerebellar atrophy. The essential function of the COG complex is dependent upon interactions with other components of trafficking machinery, such as Rab-GTPases and SNAREs. COG-interacting Rabs and SNAREs have been implicated in neurodegenerative diseases like Alzheimer’s disease and Parkinson’s disease. Defects in Golgi maintenance disrupts trafficking and processing of essential proteins, frequently associated with and contributing to compromised neuron function and human disease. Despite the recent advances in molecular neuroscience, the subcellular bases for most neurodegenerative diseases are poorly understood. This article gives an overview of the potential contributions of the COG complex and its Rab and SNARE partners in the pathogenesis of different neurodegenerative disorders.

Intersystem crossing in complex molecules

International Nuclear Information System (INIS)

Pappalardo, R.G.

1980-01-01

The general question of singlet-triplet intersystem crossing is addressed in the context of large organic molecules, i.e., ''complex'' molecules capable of self-relaxation in the absence of collisions. Examples of spectral properties of such molecules in the vapor phase are discussed, relying on extensive Russian literature in this area. Formal expressions for the relaxation rate in the electronic excited states are derived on the basis of the formalism of collision theory, and are applied to the specific case of intersystem crossing. The derivation of the ''energy-gap'' law for triplet-singlet conversion in aromatic hydrocarbons is briefly outlined. The steep rise of internal conversion rates as a function of excess excitation energy, and its competition with the intersystem crossing process, are reviewed for the case of naphthalene vapor. A general expression for the spin-orbit interaction Hamiltonian in molecular systems is outlined. Experimental observations on singlet-triplet conversion rates and the factors that can drastically affect such rates are discussed, with emphasis on the ''in- ternal'' and ''external'' heavy-atom effects. Basic relations of ESR spectroscopy and magnetophotoselection are reviewed. Technological implications of the singlet-triplet crossing in complex molecules are discussed in the context of chelate lasers, dye lasers and luminescent displays. Effects related to singlet-triplet crossing, and generally to excited-state energy-transfer in biological systems, are exemplified by the role of aromatic amino-acids in the phosphorescence of proteins, by some recent studies of energy-transfer in models of biomembranes, and by the clustering of triplet-energy donor-acceptor pairs in micelles

Product development strategy in the Danish agricultural complex: Global interaction with clusters of marketing excellence

DEFF Research Database (Denmark)

Kristensen, Preben Sander

1992-01-01

A study of the Danish foods industry shows that producers of food products have built up and maintain development of end-user products in interaction with customers in distant sophisticated markets. Concurrently, the Danish agro-industrial complex been singled out in other studies as a paradigmatic...... produce and utilize sticky and fastchanging information about production and markets respectively. It is precisely by not interacting wi market business-to-business demand from changing end-user market that the Danish agro-industrial complex has avoided being insulated. The managerial implication...... is that a company in search of partners for joint development in global agro-industra networks can realize a competitive advantage by applying a market view that is euclidean upstream and equidstant downstream....

Is there Complex Trauma Experience typology for Australian's experiencing extreme social disadvantage and low housing stability?

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Keane, Carol A; Magee, Christopher A; Kelly, Peter J

2016-11-01

Traumatic childhood experiences predict many adverse outcomes in adulthood including Complex-PTSD. Understanding complex trauma within socially disadvantaged populations has important implications for policy development and intervention implementation. This paper examined the nature of complex trauma experienced by disadvantaged individuals using a latent class analysis (LCA) approach. Data were collected through the large-scale Journeys Home Study (N=1682), utilising a representative sample of individuals experiencing low housing stability. Data on adverse childhood experiences, adulthood interpersonal trauma and relevant covariates were collected through interviews at baseline (Wave 1). Latent class analysis (LCA) was conducted to identify distinct classes of childhood trauma history, which included physical assault, neglect, and sexual abuse. Multinomial logistic regression investigated childhood relevant factors associated with class membership such as biological relationship of primary carer at age 14 years and number of times in foster care. Of the total sample (N=1682), 99% reported traumatic adverse childhood experiences. The most common included witnessing of violence, threat/experience of physical abuse, and sexual assault. LCA identified six distinct childhood trauma history classes including high violence and multiple traumas. Significant covariate differences between classes included: gender, biological relationship of primary carer at age 14 years, and time in foster care. Identification of six distinct childhood trauma history profiles suggests there might be unique treatment implications for individuals living in extreme social disadvantage. Further research is required to examine the relationship between these classes of experience, consequent impact on adulthood engagement, and future transitions though homelessness. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pharmacokinetic drug-drug interaction and their implication in clinical management

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Palleria Caterina

2013-01-01

Full Text Available Drug-drug interactions (DDIs are one of the commonest causes of medication error in developed countries, particularly in the elderly due to poly-therapy, with a prevalence of 20-40%. In particular, poly-therapy increases the complexity of therapeutic management and thereby the risk of clinically important DDIs, which can both induce the development of adverse drug reactions or reduce the clinical efficacy. DDIs can be classify into two main groups: pharmacokinetic and pharmacodynamic. In this review, using Medline, PubMed, Embase, Cochrane library and Reference lists we searched articles published until June 30 2012, and we described the mechanism of pharmacokinetic DDIs focusing the interest on their clinical implications.

Women's health, men's health, and gender and health: implications of intersectionality.

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Hankivsky, Olena

2012-06-01

Although intersectionality is now recognized in the context of women's health, men's health, and gender and health, its full implications for research, policy, and practice have not yet been interrogated. This paper investigates, from an intersectionality perspective, the common struggles within each field to confront the complex interplay of factors that shape health inequities. Drawing on developments within intersectionality scholarship and various sources of research and policy evidence (including examples from the field of HIV/AIDS), the paper demonstrates the methodological feasibility of intersectionality and in particular, the wide-ranging benefits of de-centering gender through intersectional analyses. Copyright © 2012 Elsevier Ltd. All rights reserved.

Turn-taking in Human Communication--Origins and Implications for Language Processing.

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Levinson, Stephen C

2016-01-01

Most language usage is interactive, involving rapid turn-taking. The turn-taking system has a number of striking properties: turns are short and responses are remarkably rapid, but turns are of varying length and often of very complex construction such that the underlying cognitive processing is highly compressed. Although neglected in cognitive science, the system has deep implications for language processing and acquisition that are only now becoming clear. Appearing earlier in ontogeny than linguistic competence, it is also found across all the major primate clades. This suggests a possible phylogenetic continuity, which may provide key insights into language evolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dynamics of translocation and substrate binding in individual complexes formed with active site mutants of {phi}29 DNA polymerase.

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Dahl, Joseph M; Wang, Hongyun; Lázaro, José M; Salas, Margarita; Lieberman, Kate R

2014-03-07

The Φ29 DNA polymerase (DNAP) is a processive B-family replicative DNAP. Fluctuations between the pre-translocation and post-translocation states can be quantified from ionic current traces, when individual Φ29 DNAP-DNA complexes are held atop a nanopore in an electric field. Based upon crystal structures of the Φ29 DNAP-DNA binary complex and the Φ29 DNAP-DNA-dNTP ternary complex, residues Tyr-226 and Tyr-390 in the polymerase active site were implicated in the structural basis of translocation. Here, we have examined the dynamics of translocation and substrate binding in complexes formed with the Y226F and Y390F mutants. The Y226F mutation diminished the forward and reverse rates of translocation, increased the affinity for dNTP in the post-translocation state by decreasing the dNTP dissociation rate, and increased the affinity for pyrophosphate in the pre-translocation state. The Y390F mutation significantly decreased the affinity for dNTP in the post-translocation state by decreasing the association rate ∼2-fold and increasing the dissociation rate ∼10-fold, implicating this as a mechanism by which this mutation impedes DNA synthesis. The Y390F dissociation rate increase is suppressed when complexes are examined in the presence of Mn(2+) rather than Mg(2+). The same effects of the Y226F or Y390F mutations were observed in the background of the D12A/D66A mutations, located in the exonuclease active site, ∼30 Å from the polymerase active site. Although translocation rates were unaffected in the D12A/D66A mutant, these exonuclease site mutations caused a decrease in the dNTP dissociation rate, suggesting that they perturb Φ29 DNAP interdomain architecture.

The relationship between the INTERMED patient complexity instrument and Level of Care Utilisation System (LOCUS).

Science.gov (United States)

Thurber, Steven; Wilson, Ann; Realmuto, George; Specker, Sheila

2018-03-01

To investigate the concurrent and criterion validity of two independently developed measurement instruments, INTERMED and LOCUS, designed to improve the treatment and clinical management of patients with complex symptom manifestations. Participants (N = 66) were selected from hospital records based on the complexity of presenting symptoms, with tripartite diagnoses across biological, psychiatric and addiction domains. Biopsychosocial information from hospital records were submitted to INTERMED and LOCUS grids. In addition, Global Assessment of Functioning (GAF) ratings were gathered for statistical analyses. The product moment correlation between INTERMED and LOCUS was 0.609 (p = .01). Inverse zero-order correlations for INTERMED and LOCUS total score and GAF were obtained. However, only the beta weight for LOCUS and GAF was significant. An exploratory principal components analysis further illuminated areas of convergence between the instruments. INTERMED and LOCUS demonstrated shared variance. INTERMED appeared more sensitive to complex medical conditions and severe physiological reactions, whereas LOCUS findings are more strongly related to psychiatric symptoms. Implications are discussed.

A nanosized Ag-silica hybrid complex prepared by γ-irradiation activates the defense response in Arabidopsis

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Chu, Hyosub; Kim, Hwa-Jung; Su Kim, Joong; Kim, Min-Soo; Yoon, Byung-Dae; Park, Hae-Jun; Kim, Cha Young

2012-02-01

Silver nanoparticles have antimicrobial activity against many pathogenic microbes. Here, the preparation of a nanosized Ag-silica hybrid complex (NSS) prepared by γ-irradiation is described. The effects of both NSS and reduced Ag nanoparticles (Ag 0) on the growth of the model plant Arabidopsis thaliana were tested. The application of 1-10 ppm NSS complex improved Arabidopsis growth in soil, whereas 100 ppm NSS resulted in weakly curled leaves. In addition, supplementation of Murashige and Skoog (MS) growth medium with 1 ppm NSS promoted the root growth of Arabidopsis seedlings, but root growth was inhibited by supplementation with 10 ppm NSS. To investigate whether the NSS complex could induce plant defense responses, the expression of pathogenesis-related ( PR) genes that are implicated in systemic acquired resistance (SAR) in Arabidopsis plants was examined. PR1, PR2 and PR5 were significantly up-regulated by each application of 10 ppm NSS complex or Ag 0 to the rosette leaves. Furthermore, pretreatment with the NSS complex induced more pathogen resistance to the virulent pathogen Pseudomonas syringae pv. tomato DC3000 ( Pst) compared to water treatment in Arabidopsis plants.

SPICE: exploration and analysis of post-cytometric complex multivariate datasets.

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Roederer, Mario; Nozzi, Joshua L; Nason, Martha C

2011-02-01

Polychromatic flow cytometry results in complex, multivariate datasets. To date, tools for the aggregate analysis of these datasets across multiple specimens grouped by different categorical variables, such as demographic information, have not been optimized. Often, the exploration of such datasets is accomplished by visualization of patterns with pie charts or bar charts, without easy access to statistical comparisons of measurements that comprise multiple components. Here we report on algorithms and a graphical interface we developed for these purposes. In particular, we discuss thresholding necessary for accurate representation of data in pie charts, the implications for display and comparison of normalized versus unnormalized data, and the effects of averaging when samples with significant background noise are present. Finally, we define a statistic for the nonparametric comparison of complex distributions to test for difference between groups of samples based on multi-component measurements. While originally developed to support the analysis of T cell functional profiles, these techniques are amenable to a broad range of datatypes. Published 2011 Wiley-Liss, Inc.

Narrative persuasion, causality, complex integration, and support for obesity policy.

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Niederdeppe, Jeff; Shapiro, Michael A; Kim, Hye Kyung; Bartolo, Danielle; Porticella, Norman

2014-01-01

Narrative messages have the potential to convey causal attribution information about complex social issues. This study examined attributions about obesity, an issue characterized by interrelated biological, behavioral, and environmental causes. Participants were randomly assigned to read one of three narratives emphasizing societal causes and solutions for obesity or an unrelated story that served as the control condition. The three narratives varied in the extent to which the character in the story acknowledged personal responsibility (high, moderate, and none) for controlling her weight. Stories that featured no acknowledgment and moderate acknowledgment of personal responsibility, while emphasizing environmental causes and solutions, were successful at increasing societal cause attributions about obesity and, among conservatives, increasing support for obesity-related policies relative to the control group. The extent to which respondents were able to make connections between individual and environmental causes of obesity (complex integration) mediated the relationship between the moderate acknowledgment condition and societal cause attributions. We conclude with a discussion of the implications of this work for narrative persuasion theory and health communication campaigns.

Scientific foundations of addressing risk in complex and dynamic environments

International Nuclear Information System (INIS)

Grotan, T.O.; Storseth, F.; Albrechtsen, E.

2011-01-01

Development, deployment and application of Information and Communication Technology (ICT) and digital infrastructure continue with unabated intensity in the petroleum-related activity on the Norwegian shelf. This development towards what is denoted Integrated Operations (IO) creates new ways of organizing work, new work processes and increased automation, e.g. closer collaboration offshore-onshore, cooperation across organizational and geographical borders. This creates new challenges for managing risk. Although there are different versions of IO today, we argue that it is possible to identify and study generic properties within such IO manifestations. The current paper focus on the potential complexity of IO in the generic sense, and some scientific implications in terms of addressing risk. The paper uses the century-old metaphor of 'wildness in wait' to engage the wide field of complexity theory in a productive way to address systemic properties of risk. The paper further uses the Cynefin sensemaking framework in order to identify and address the crucial distinction between directed (resultant) and un-directed (emergent) order. The paper finally discusses the importance of seeing risk assessment as a social knowledge practice.

Complex chemistry

International Nuclear Information System (INIS)

Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

2006-06-01

This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.

ADHD and adolescent EFL learners’ speaking complexity, accuracy, and fluency in English

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Hamid Marashi

2016-07-01

Full Text Available This study was an attempt to investigate the relationships among Attention-Deficit/ Hyperactivity Disorder (ADHD and speaking complexity, accuracy, and fluency (CAF among Iranian EFL learners. To fulfill the purpose of this study, the teachers and parents of 593 male students were given the Farsi version of the CSI-4 ADHD diagnostic questionnaire, out of which 61 students scored above the cut-off score of nine in both the teacher and parent questionnaires. These students then sat for a sample speaking section of the Key English Test (KET; the interviews were scored by two raters according to the measures of CAF. The data were thus analyzed and the results revealed a significant positive correlation between ADHD and speaking fluency; in contrast, a significant negative correlation was observed between ADHD and speaking complexity and ADHD and speaking accuracy. The regressions disclosed that ADHD is a significant predictor of complexity, accuracy, and fluency in speaking. The findings of this study have pedagogical implications for both parents and teachers in contact with students with ADHD with respect to the importance of identifying such students and thus planning and monitoring their progress.

Reversible alkyne insertion in the benzannulation reaction of Fischer carbene complexes with alkynes

Energy Technology Data Exchange (ETDEWEB)

Waters, M.L.; Bos, M.E.; Wulff, W.D. [Univ. of Chicago, IL (United States)

1995-12-31

The benzannulation reaction of Fischer carbene complexes with alkynes to give phenols is highly regioselective with terminal alkynes, and reasonably regioselective with internal alkynes. This has been attributed to steric factors in intermediates, where one form is favored due to close contact between the R substituent and a cis-CO ligand. Whether alkyne insertion is kinetically or thermodynamically controlled has not been determined. The authors now have evidence from regioselectivity studies that alkyne insertion into the metal-carbon bond is reversible. Implications of these results and further mechanistic considerations will be presented.

Assessing complexity of skin blood flow oscillations in response to locally applied heating and pressure in rats: Implications for pressure ulcer risk

Science.gov (United States)

Liao, Fuyuan; O'Brien, William D.; Jan, Yih-Kuen

2013-10-01

The objective of this study was to investigate the effects of local heating on the complexity of skin blood flow oscillations (BFO) under prolonged surface pressure in rats. Eleven Sprague-Dawley rats were studied: 7 rats underwent surface pressure with local heating (△t=10 °C) and 4 rats underwent pressure without heating. A pressure of 700 mmHg was applied to the right trochanter area of rats for 3 h. Skin blood flow was measured using laser Doppler flowmetry. The loading period was divided into nonoverlapping 30 min epochs. For each epoch, multifractal detrended fluctuation analysis (MDFA) was utilized to compute DFA coefficients and complexity of endothelial related metabolic, neurogenic, and myogenic frequencies of BFO. The results showed that under surface pressure, local heating led to a significant decrease in DFA coefficients of myogenic frequency during the initial epoch of loading period, a sustained decrease in complexity of myogenic frequency, and a significantly higher degree of complexity of metabolic frequency during the later phase of loading period. Surrogate tests showed that the reduction in complexity of myogenic frequency was associated with a loss of nonlinearity whereas increased complexity of metabolic frequency was associated with enhanced nonlinearity. Our results indicate that increased metabolic activity and decreased myogenic response due to local heating manifest themselves not only in magnitudes of metabolic and myogenic frequencies but also in their structural complexity. This study demonstrates the feasibility of using complexity analysis of BFO to monitor the ischemic status of weight-bearing skin and risk of pressure ulcers.

Weighted Complex Network Analysis of Shanghai Rail Transit System

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Yingying Xing

2016-01-01

Full Text Available With increasing passenger flows and construction scale, Shanghai rail transit system (RTS has entered a new era of networking operation. In addition, the structure and properties of the RTS network have great implications for urban traffic planning, design, and management. Thus, it is necessary to acquire their network properties and impacts. In this paper, the Shanghai RTS, as well as passenger flows, will be investigated by using complex network theory. Both the topological and dynamic properties of the RTS network are analyzed and the largest connected cluster is introduced to assess the reliability and robustness of the RTS network. Simulation results show that the distribution of nodes strength exhibits a power-law behavior and Shanghai RTS network shows a strong weighted rich-club effect. This study also indicates that the intentional attacks are more detrimental to the RTS network than to the random weighted network, but the random attacks can cause slightly more damage to the random weighted network than to the RTS network. Our results provide a richer view of complex weighted networks in real world and possibilities of risk analysis and policy decisions for the RTS operation department.

Reflective practice and its implications for pharmacy education.

Science.gov (United States)

Tsingos, Cherie; Bosnic-Anticevich, Sinthia; Smith, Lorraine

2014-02-12

Pharmacy students require critical-thinking and problem-solving skills to integrate theory learned in the classroom with the complexities of practice, yet many pharmacy students fall short of acquiring these skills.(1-2) Reflective practice activities encourage learning from the student's own experiences and those of others, and offer a possible solution for the integration of knowledge-based curricula with the ambiguities of practice, as well as enhance communication and collaboration within a multidisciplinary team. Although reflective practices have been embraced elsewhere in health professions education, their strengths and shortcomings need to be considered when implementing such practices into pharmacy curricula. This review provides an overview of the evolution of theories related to reflective practice, critically examines the use of reflective tools (such as portfolios and blogs), and discusses the implications of implementing reflective practices in pharmacy education.

Anatomical Network Analysis Shows Decoupling of Modular Lability and Complexity in the Evolution of the Primate Skull

Science.gov (United States)

Esteve-Altava, Borja; Boughner, Julia C.; Diogo, Rui; Villmoare, Brian A.; Rasskin-Gutman, Diego

2015-01-01

Modularity and complexity go hand in hand in the evolution of the skull of primates. Because analyses of these two parameters often use different approaches, we do not know yet how modularity evolves within, or as a consequence of, an also-evolving complex organization. Here we use a novel network theory-based approach (Anatomical Network Analysis) to assess how the organization of skull bones constrains the co-evolution of modularity and complexity among primates. We used the pattern of bone contacts modeled as networks to identify connectivity modules and quantify morphological complexity. We analyzed whether modularity and complexity evolved coordinately in the skull of primates. Specifically, we tested Herbert Simon’s general theory of near-decomposability, which states that modularity promotes the evolution of complexity. We found that the skulls of extant primates divide into one conserved cranial module and up to three labile facial modules, whose composition varies among primates. Despite changes in modularity, statistical analyses reject a positive feedback between modularity and complexity. Our results suggest a decoupling of complexity and modularity that translates to varying levels of constraint on the morphological evolvability of the primate skull. This study has methodological and conceptual implications for grasping the constraints that underlie the developmental and functional integration of the skull of humans and other primates. PMID:25992690

Reality and dimension of space and the complexity of quantum mechanics

International Nuclear Information System (INIS)

Mirman, R.

1988-01-01

The dimension (and signature) of space is a result of distances being real numbers and quantum mechanical state functions being complex ones; it is an inescapable consequence of quantum mechanics and group theory. So nonrelativistic quantum mechanics cannot be complete (it requires ad hoc additional assumptions) and consistent (nor can classical physics), leading to relativity, quantum mechanics, and field theory. Implications of the constraints of consistency and physical reasonableness and of group theory for the structure of these theories are considered. It appears that there are simple, perhaps unavoidable reasons for the laws of physics, the nature of the world they describe, and the space in which they act

Adaptation to High Ethanol Reveals Complex Evolutionary Pathways.

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Karin Voordeckers

2015-11-01

Full Text Available Tolerance to high levels of ethanol is an ecologically and industrially relevant phenotype of microbes, but the molecular mechanisms underlying this complex trait remain largely unknown. Here, we use long-term experimental evolution of isogenic yeast populations of different initial ploidy to study adaptation to increasing levels of ethanol. Whole-genome sequencing of more than 30 evolved populations and over 100 adapted clones isolated throughout this two-year evolution experiment revealed how a complex interplay of de novo single nucleotide mutations, copy number variation, ploidy changes, mutator phenotypes, and clonal interference led to a significant increase in ethanol tolerance. Although the specific mutations differ between different evolved lineages, application of a novel computational pipeline, PheNetic, revealed that many mutations target functional modules involved in stress response, cell cycle regulation, DNA repair and respiration. Measuring the fitness effects of selected mutations introduced in non-evolved ethanol-sensitive cells revealed several adaptive mutations that had previously not been implicated in ethanol tolerance, including mutations in PRT1, VPS70 and MEX67. Interestingly, variation in VPS70 was recently identified as a QTL for ethanol tolerance in an industrial bio-ethanol strain. Taken together, our results show how, in contrast to adaptation to some other stresses, adaptation to a continuous complex and severe stress involves interplay of different evolutionary mechanisms. In addition, our study reveals functional modules involved in ethanol resistance and identifies several mutations that could help to improve the ethanol tolerance of industrial yeasts.

Architecture of human mTOR complex 1.

Science.gov (United States)

Aylett, Christopher H S; Sauer, Evelyn; Imseng, Stefan; Boehringer, Daniel; Hall, Michael N; Ban, Nenad; Maier, Timm

2016-01-01

Target of rapamycin (TOR), a conserved protein kinase and central controller of cell growth, functions in two structurally and functionally distinct complexes: TORC1 and TORC2. Dysregulation of mammalian TOR (mTOR) signaling is implicated in pathologies that include diabetes, cancer, and neurodegeneration. We resolved the architecture of human mTORC1 (mTOR with subunits Raptor and mLST8) bound to FK506 binding protein (FKBP)-rapamycin, by combining cryo-electron microscopy at 5.9 angstrom resolution with crystallographic studies of Chaetomium thermophilum Raptor at 4.3 angstrom resolution. The structure explains how FKBP-rapamycin and architectural elements of mTORC1 limit access to the recessed active site. Consistent with a role in substrate recognition and delivery, the conserved amino-terminal domain of Raptor is juxtaposed to the kinase active site. Copyright © 2016, American Association for the Advancement of Science.

Innovation versus complexity: what is too much of a good thing?

Science.gov (United States)

Gottfredson, Mark; Aspinall, Keith

2005-11-01

What's the number of product or service offerings that would optimize both your revenues and your profits? For most firms, it's considerably lower than the number they offer today. The fact is, companies have strong incentives to be overly innovative in new product development. But continual launches of new products and line extensions add complexity throughout a company's operations, and as the costs of managing that complexity multiply, margins shrink. To maximize profit potential, a company needs to identify its innovation fulcrum, the point at which an additional offering destroys more value than it creates. The usual antidotes to complexity miss their mark because they treat the problem on the factory floor rather than at its source: in the product line. Mark Gottfredson and Keith Aspinall of Bain & Company present an approach that goes beyond the typical Six Sigma or lean-operations program to root out complexity hidden in the value chain. The first step is to ask, What would our company look like if it made and sold only a single product or service? In other words, you identify your company's equivalent of Henry Ford's one-size-fits-all Model T-for Starbucks, it might be a medium-size cup of coffee; for a bank, a simple checking account-and then determine the cost of producing that baseline offering. Next, you add variety back into the business system, product by product, and carefully forecast the resulting impact on sales as well as the cost implications across the value chain. When the analysis shows the costs beginning to overwhelm the added revenues, you've found your innovation fulcrum. By deconstructing their companies to a zero-complexity baseline, managers can break through organizational resistance and deeply entrenched ways of thinking to find the right balance between innovation and complexity.

Mitochondrial impairment by PPAR agonists and statins identified via immunocaptured OXPHOS complex activities and respiration

International Nuclear Information System (INIS)

Nadanaciva, Sashi; Dykens, James A.; Bernal, Autumn; Capaldi, Roderick A.; Will, Yvonne

2007-01-01

Mitochondrial impairment is increasingly implicated in the etiology of toxicity caused by some thiazolidinediones, fibrates, and statins. We examined the effects of members of these drug classes on respiration of isolated rat liver mitochondria using a phosphorescent oxygen sensitive probe and on the activity of individual oxidative phosphorylation (OXPHOS) complexes using a recently developed immunocapture technique. Of the six thiazolidinediones examined, ciglitazone, troglitazone, and darglitazone potently disrupted mitochondrial respiration. In accord with these data, ciglitazone and troglitazone were also potent inhibitors of Complexes II + III, IV, and V, while darglitazone predominantly inhibited Complex IV. Of the six statins evaluated, lovastatin, simvastatin, and cerivastatin impaired mitochondrial respiration the most, with simvastatin and lovastatin impairing multiple OXPHOS Complexes. Within the class of fibrates, gemfibrozil more potently impaired respiration than fenofibrate, clofibrate, or ciprofibrate. Gemfibrozil only modestly inhibited Complex I, fenofibrate inhibited Complexes I, II + III, and V, and clofibrate inhibited Complex V. Our findings with the two complementary methods indicate that (1) some members of each class impair mitochondrial respiration, whereas others have little or no effect, and (2) the rank order of mitochondrial impairment accords with clinical adverse events observed with these drugs. Since the statins are frequently co-prescribed with the fibrates or thiazolidinediones, various combinations of these three drug classes were also analyzed for their mitochondrial effects. In several cases, the combination additively uncoupled or inhibited respiration, suggesting that some combinations are more likely to yield clinically relevant drug-induced mitochondrial side effects than others

'Fractional recovery' analysis of a presynaptic synaptotagmin 1-anchored endocytic protein complex.

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Rajesh Khanna

Full Text Available BACKGROUND: The integral synaptic vesicle protein and putative calcium sensor, synaptotagmin 1 (STG, has also been implicated in synaptic vesicle (SV recovery. However, proteins with which STG interacts during SV endocytosis remain poorly understood. We have isolated an STG-associated endocytic complex (SAE from presynaptic nerve terminals and have used a novel fractional recovery (FR assay based on electrostatic dissociation to identify SAE components and map the complex structure. The location of SAE in the presynaptic terminal was determined by high-resolution quantitative immunocytochemistry at the chick ciliary ganglion giant calyx-type synapse. METHODOLOGY/PRINCIPLE FINDINGS: The first step in FR analysis was to immunoprecipitate (IP the complex with an antibody against one protein component (the IP-protein. The immobilized complex was then exposed to a high salt (1150 mM stress-test that caused shedding of co-immunoprecipitated proteins (co-IP-proteins. A Fractional Recovery ratio (FR: recovery after high salt/recovery with control salt as assayed by Western blot was calculated for each co-IP-protein. These FR values reflect complex structure since an easily dissociated protein, with a low FR value, cannot be intermediary between the IP-protein and a salt-resistant protein. The structure of the complex was mapped and a blueprint generated with a pair of FR analyses generated using two different IP-proteins. The blueprint of SAE contains an AP180/X/STG/stonin 2/intersectin/epsin core (X is unknown and epsin is hypothesized, and an AP2 adaptor, H-/L-clathrin coat and dynamin scission protein perimeter. Quantitative immunocytochemistry (ICA/ICQ method at an isolated calyx-type presynaptic terminal indicates that this complex is associated with STG at the presynaptic transmitter release face but not with STG on intracellular synaptic vesicles. CONCLUSIONS/SIGNIFICANCE: We hypothesize that the SAE serves as a recognition site and also as a

Geology of McLaughlin Crater, Mars: A Unique Lacustrine Setting with Implications for Astrobiology

Science.gov (United States)

Michalski, J. R.; Niles, P. B.; Rogers, A. D.; Johnson, S. S.; Ashley, J. W.; Golombek, M. P.

2016-01-01

McLaughlin crater is a 92-kmdiameter Martian impact crater that contained an ancient carbonate- and clay mineral-bearing lake in the Late Noachian. Detailed analysis of the geology within this crater reveals a complex history with important implications for astrobiology [1]. The basin contains evidence for, among other deposits, hydrothermally altered rocks, delta deposits, deep water (>400 m) sediments, and potentially turbidites. The geology of this basin stands in stark contrast to that of some ancient basins that contain evidence for transient aqueous processes and airfall sediments (e.g. Gale Crater [2-3]).

A genomic pathway approach to a complex disease: axon guidance and Parkinson disease.

Directory of Open Access Journals (Sweden)

Timothy G Lesnick

2007-06-01

Full Text Available While major inroads have been made in identifying the genetic causes of rare Mendelian disorders, little progress has been made in the discovery of common gene variations that predispose to complex diseases. The single gene variants that have been shown to associate reproducibly with complex diseases typically have small effect sizes or attributable risks. However, the joint actions of common gene variants within pathways may play a major role in predisposing to complex diseases (the paradigm of complex genetics. The goal of this study was to determine whether polymorphism in a candidate pathway (axon guidance predisposed to a complex disease (Parkinson disease [PD]. We mined a whole-genome association dataset and identified single nucleotide polymorphisms (SNPs that were within axon-guidance pathway genes. We then constructed models of axon-guidance pathway SNPs that predicted three outcomes: PD susceptibility (odds ratio = 90.8, p = 4.64 x 10(-38, survival free of PD (hazards ratio = 19.0, p = 5.43 x 10(-48, and PD age at onset (R(2 = 0.68, p = 1.68 x 10(-51. By contrast, models constructed from thousands of random selections of genomic SNPs predicted the three PD outcomes poorly. Mining of a second whole-genome association dataset and mining of an expression profiling dataset also supported a role for many axon-guidance pathway genes in PD. These findings could have important implications regarding the pathogenesis of PD. This genomic pathway approach may also offer insights into other complex diseases such as Alzheimer disease, diabetes mellitus, nicotine and alcohol dependence, and several cancers.

Adsorption of Pb{sup 2+} and Cd{sup 2+} onto a novel activated carbon-chitosan complex

Energy Technology Data Exchange (ETDEWEB)

Ge, H.; Fan, X. [College of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640 (China)

2011-10-15

A novel activated carbon-chitosan complex adsorbent (ACCA) was prepared via the crosslinking of glutaraldehyde and activated carbon-(NH{sub 2}-protected) chitosan complex under microwave irradiation. The surface morphology of this adsorbent was characterized. The adsorption of ACCA for Pb{sup 2+} and Cd{sup 2+} was investigated. The results demonstrate that ACCA has higher adsorption capacity than chitosan. The adsorption follows pseudo first-order kinetics. The isotherm adsorption equilibria are better described by Freundlich and Dubinin-Radushkevich isotherms than by the Langmuir isotherm. The adsorbent can be recycled. These results have important implications for the design of low-cost and effective adsorbents in the removal of heavy metal ions from wastewaters. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Environment-dependent regulation of spliceosome activity by the LSM2-8 complex in Arabidopsis.

Science.gov (United States)

Carrasco-López, Cristian; Hernández-Verdeja, Tamara; Perea-Resa, Carlos; Abia, David; Catalá, Rafael; Salinas, Julio

2017-07-07

Spliceosome activity is tightly regulated to ensure adequate splicing in response to internal and external cues. It has been suggested that core components of the spliceosome, such as the snRNPs, would participate in the control of its activity. The experimental indications supporting this proposition, however, remain scarce, and the operating mechanisms poorly understood. Here, we present genetic and molecular evidence demonstrating that the LSM2-8 complex, the protein moiety of the U6 snRNP, regulates the spliceosome activity in Arabidopsis, and that this regulation is controlled by the environmental conditions. Our results show that the complex ensures the efficiency and accuracy of constitutive and alternative splicing of selected pre-mRNAs, depending on the conditions. Moreover, miss-splicing of most targeted pre-mRNAs leads to the generation of nonsense mediated decay signatures, indicating that the LSM2-8 complex also guarantees adequate levels of the corresponding functional transcripts. Interestingly, the selective role of the complex has relevant physiological implications since it is required for adequate plant adaptation to abiotic stresses. These findings unveil an unanticipated function for the LSM2-8 complex that represents a new layer of posttranscriptional regulation in response to external stimuli in eukaryotes. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Apparent partition coefficient in octanol-water and binding percentage to BSA of 153Sm(113,117Snm) complexes

International Nuclear Information System (INIS)

Yang Yuqing; Luo Shunzhong; Wang Guanquan; He Jiaheng; Bing Wenzeng; Pu Manfei; Wei Hongyuan; Wang Wenjin

2004-01-01

Apparent partition coefficient in octanol-water and binding percentage to BSA of 153 Sm-NTMP, 153 Sm-HEDTMP, 153 Sm-DCTMP, 153 Sm-EDTMP, 153 Sm-DTPMP, 113,117 Sn m -EDTMP, 113,117 Sn m -HEDTMP, 113,117 Sn m -DTPMP are measured. The results show that there is a linear relationship between the relative magnitude of the apparent partition coefficient in octanol-water and the relative magnitude of the binding percentage to BSA of these 153 Sm( 113,117 Sn m ) complexes. This linear relationship provides a new method for determination of the apparent partition coefficient in octanol-water of 153 Sm( 113,117 Sn m ) complexes of this kind. This linear relationship also implicates that hydrophobic force plays an important role in the binding of 153 Sm( 113,117 Sn m ) complexes to BSA

Complexity Theories of Cities Have Come of Age An Overview with Implications to Urban Planning and Design

CERN Document Server

Meyer, Han; Stolk, Egbert; Tan, Ekim

2012-01-01

Today, our cities are an embodiment of the complex, historical evolution of knowledge, desires and technology. Our planned and designed activities co-evolve with our aspirations, mediated by the existing technologies and social structures.  The city represents the accretion and accumulation of successive layers of collective activity, structuring and being structured by other, increasingly distant cities, reaching now right around the globe. This historical and structural development cannot therefore be understood or captured by any set of fixed quantitative relations. Structural changes imply that the patterns of growth, and their underlying reasons change over time, and therefore that any attempt to control the morphology of cities and their patterns of flow by means of planning and design, must be dynamical, based on the mechanisms that drive the changes occurring at a given moment. This carefully edited post-proceedings volume gathers a snapshot view by leading researchers in field, of current complexity...

Heptachlor induced mitochondria-mediated cell death via impairing electron transport chain complex III

International Nuclear Information System (INIS)

Hong, Seokheon; Kim, Joo Yeon; Hwang, Joohyun; Shin, Ki Soon; Kang, Shin Jung

2013-01-01

Highlights: •Heptachlor inhibited mitochondrial electron transport chain complex III activity. •Heptachlor promoted generation of reactive oxygen species. •Heptachlor induced Bax activation. •Heptachlor induced mitochondria-mediated and caspase-dependent apoptosis. -- Abstract: Environmental toxins like pesticides have been implicated in the pathogenesis of Parkinson’s disease (PD). Epidemiological studies suggested that exposures to organochlorine pesticides have an association with an increased PD risk. In the present study, we examined the mechanism of toxicity induced by an organochlorine pesticide heptachlor. In a human dopaminergic neuroblastoma SH-SY5Y cells, heptachlor induced both morphological and functional damages in mitochondria. Interestingly, the compound inhibited mitochondrial electron transport chain complex III activity. Rapid generation of reactive oxygen species and the activation of Bax were then detected. Subsequently, mitochondria-mediated, caspase-dependent apoptosis followed. Our results raise a possibility that an organochlorine pesticide heptachlor can act as a neurotoxicant associated with PD

Heptachlor induced mitochondria-mediated cell death via impairing electron transport chain complex III

Energy Technology Data Exchange (ETDEWEB)

Hong, Seokheon; Kim, Joo Yeon; Hwang, Joohyun [Department of Molecular Biology, Sejong University, Seoul 143-747 (Korea, Republic of); Shin, Ki Soon [Department of Biology, Department of Life and Nanopharmaceutical Sciences, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kang, Shin Jung, E-mail: sjkang@sejong.ac.kr [Department of Molecular Biology, Sejong University, Seoul 143-747 (Korea, Republic of)

2013-08-09

Highlights: •Heptachlor inhibited mitochondrial electron transport chain complex III activity. •Heptachlor promoted generation of reactive oxygen species. •Heptachlor induced Bax activation. •Heptachlor induced mitochondria-mediated and caspase-dependent apoptosis. -- Abstract: Environmental toxins like pesticides have been implicated in the pathogenesis of Parkinson’s disease (PD). Epidemiological studies suggested that exposures to organochlorine pesticides have an association with an increased PD risk. In the present study, we examined the mechanism of toxicity induced by an organochlorine pesticide heptachlor. In a human dopaminergic neuroblastoma SH-SY5Y cells, heptachlor induced both morphological and functional damages in mitochondria. Interestingly, the compound inhibited mitochondrial electron transport chain complex III activity. Rapid generation of reactive oxygen species and the activation of Bax were then detected. Subsequently, mitochondria-mediated, caspase-dependent apoptosis followed. Our results raise a possibility that an organochlorine pesticide heptachlor can act as a neurotoxicant associated with PD.

The Formation of Complex Organic Compounds in Astrophysical Ices and their Implications for Astrobiology

Science.gov (United States)

Sandford, Scott A.

2015-01-01

Ices in astrophysical environments are generally dominated by very simple molecules like H2O, CH3OH, CH4, NH3, CO, CO2, etc, although they likely contain PAHs as well. These molecules, particularly H2O, are of direct interest to astrobiology in-and-of themselves since they represent some of the main carriers of the biogenic elements C, H, O, and N. In addition, these compounds are present in the dense interstellar clouds in which new stars and planetary systems are formed and may play a large role in the delivery of volatiles and organics to the surfaces of new planets. However, these molecules are all far simpler than the more complex organic compounds found in living systems.

Agent-Based and Macroscopic Modeling of the Complex Socio-Economic Systems

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Aleksejus Kononovičius

2013-08-01

Full Text Available Purpose – The focus of this contribution is the correspondence between collective behavior and inter-individual interactions in the complex socio-economic systems. Currently there is a wide selection of papers proposing various models for the both collective behavior and inter-individual interactions in the complex socio-economic systems. Yet the papers directly relating these two concepts are still quite rare. By studying this correspondence we discuss a cutting edge approach to the modeling of complex socio-economic systems. Design/methodology/approach – The collective behavior is often modeled using stochastic and ordinary calculus, while the inter-individual interactions are modeled using agent-based models. In order to obtain the ideal model, one should start from these frameworks and build a bridge to reach another. This is a formidable task, if we consider the top-down approach, namely starting from the collective behavior and moving towards inter-individual interactions. The bottom-up approach also fails, if complex inter-individual interaction models are considered, yet in this case we can start with simple models and increase the complexity as needed. Findings – The bottom-up approach, considering simple agent-based herding model as a model for the inter-individual interactions, allows us to derive certain macroscopic models of the complex socio-economic systems from the agent-based perspective. This provides interesting insights into the collective behavior patterns observed in the complex socio-economic systems. Research limitations/implications –The simplicity of the agent-based herding model might be considered to be somewhat limiting. Yet this simplicity implies that the model is highly universal. It reproduces universal features of social behavior and also can be further extended to fit different socio-economic scenarios. Practical implications – Insights provided in this contribution might be used to modify existing

Implications of Antiphospholipid and Antineutrophilic Cytoplasmic Antibodies in the Context of Postinfectious Glomerulonephritis

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Daniel Leifer

2017-01-01

Full Text Available While antineutrophil cytoplasmic antibody (ANCA positivity has been documented in some patients with postinfectious glomerulonephritis (PIGN and is associated with more severe disease, antiphospholipid antibodies (APA are not known to be a common occurrence. We describe a child with severe acute kidney injury who was noted to have prolonged positivity of both ANCA and APA; a renal biopsy showed noncrescentic immune complex mediated glomerulonephritis with subepithelial deposits compatible with PIGN. He recovered without maintenance immunosuppressive therapy and at last follow-up had normal renal function. We discuss the cooccurrence and implications of ANCA and APA in children with PIGN.

Mechanisms of radiation oncogenesis and their implications for radiological protection

International Nuclear Information System (INIS)

Cox, R.

1992-01-01

Studies on the genetics, cytogenetics, biochemistry and molecular biology of neoplasia are now beginning to provide us with an increasingly coherent picture of cancer induction and development. Some of the genes involved in this complex multi-step cellular process have been isolated and characterized and in a few instances it is possible to identify target genes for the initiation of specific neoplasms and how these genes are mutated by environmental carcinogens. Knowledge of molecular mechanisms of mammalian DNA repair and mutagenesis has similarly increased and, together with limited studies of molecular mechanisms of radiation oncogenesis in animal systems, allows specific comment on the molecular nature of radiation-induced initiating events for neoplasia. These data are discussed with an emphasis on their possible implications for radiological protection. (author)

The Stoichiometric Interaction of the Hsp90-Sgt1-Rar1 Complex by CD and SRCD Spectroscopy

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Giuliano Siligardi

2018-01-01

Full Text Available While the molecular details by which Hsp90 interacts with Sgt1 and Rar1 were previously described the exact stoichiometric complex that is formed remains elusive. Several possibilities remain that include two asymmetric complexes, Sgt12-Hsp902-Rar12 (two molecules of Sgt1 and Rar1 and one Hsp90 dimer or Sgt12-Hsp902-Rar11 (with a single Rar1 molecule and an asymmetric complex (Sgt11-Hsp902-Rar11. The Hsp90-mediated activation of NLR receptors (Nucleotide-binding domain and Leucine-rich Repeat in the innate immunity of both plants and animals is dependent on the co-chaperone Sgt1 and in plants on Rar1, a cysteine- and histidine-rich domain (CHORD-containing protein. The exact stoichiometry of such a complex may have a direct impact on NLR protein oligomerization and thus ultimately on the mechanism by which NLRs are activated. CD spectroscopy was successfully used to determine the stoichiometry of a ternary protein complex among Hsp90, Sgt1, and Rar1 in the presence of excess ADP. The results indicated that a symmetric Sgt12-Hsp902-Rar11 complex was formed that could allow two NLR molecules to simultaneously bind. The stoichiometry of this complex has implications on, and might promote, the dimerization of NLR proteins following their activation.

Anisotropy of the proton spin--lattice relaxation time in the superconducting intercalation complex TaS2(NH3): Structural and bonding implications

International Nuclear Information System (INIS)

Gamble, F.R.; Silbernagel, B.G.

1975-01-01

The nature of the interaction responsible for the formation of molecular intercalation complexes between Lewis bases and layered transition metal dichalcogenides is not well understood. To some extent this is due to a lack of structural information. A prototype of these complexes is TaS 2 (NH 3 ), in which monolayers of ammonia are inserted between the metallic, superconducting layers of TaS 2 . The compound is crystalline and stoichiometric. Measurement of the anisotropy of the proton spin--lattice relaxation time at 300 degreeK indicates that the molecular threefold symmetry axis is not perpendicular to the disulfide layers as suggested by other workers, but is parallel to the layers. This orientation precludes direct interaction between the molecular lone pair orbital and the transition metal atoms. The interactions governing the structure of this complex may be similar to those obtaining in the intercalation complexes between TaS 2 and a number of substituted pyridines, in which complexes the axis of the lone pair orbital is also parallel to the layers

Zircon U-Pb geochronology and geochemistry of granites in the Zhuguangshan complex, South China: Implications for uranium mineralization

Science.gov (United States)

Zhang, Long; Chen, Zhenyu; Li, Xiaofeng; Li, Shengrong; Santosh, M.; Huang, Guolong

2018-05-01

The Zhuguangshan complex, composed of Caledonian, Indosinian, and Yanshanian granites, and Cretaceous mafic dykes, is one of the most important granite-hosted uranium producers in South China. Here we present LA-ICP-MS zircon U-Pb and hornblende 40Ar/39Ar geochronology and whole-rock and biotite geochemistry for the granites in this complex to evaluate the magmatism and its constraints on uranium mineralization. Samples collected from the Fuxi, Youdong, Longhuashan, Chikeng, Qiling, and Sanjiangkou intrusions yield zircon weighted 206Pb/238U ages of 426.7 ± 5.4 Ma, 226.4 ± 3.5 Ma, 225.0 ± 2.7 Ma, 152.2 ± 3.0 Ma, 153.9 ± 2.1 Ma, and 155.2 ± 2.1 Ma, respectively. A new Ar-Ar dating of the hornblende of the diabase from the Changjiang uranium ore field yields a plateau age of 145.1 ± 1.5 Ma. These results coupled with published geochronological data indicate that six major magmatic events occurred in the study area at 420-435 Ma, 225-240 Ma, 150-165 Ma, 140 Ma, 105 Ma, and 90 Ma. Both U-bearing and barren granites occur in this complex, and they display differences in whole-rock and biotite geochemistry. The barren granites show higher Al2O3, CaO, TFMM, Rb, Zr, Ba, SI, Mg#, (La/Yb)N, and Eu/Eu*, but lower SiO2, ALK, Rb, DI, Rb/Sr, and TiO2/MgO than those of the U-bearing granites. Biotites in the U-bearing granites are close to the Fe-rich siderophyllite-annite end member with Fe/(Fe + Mg) ratios higher than 0.66, whereas those in the barren granites are relatively close to the Mg-rich eastonite-phlogopite end member with Fe/(Fe + Mg) ratios uranium ore potential of the granites in the Zhuguangshan complex. The geochemical variations of U-bearing and barren granites can serve as a potential detector for granite-hosted uranium deposits.

Ligand extraction of rare earth elements from aquifer sediments: Implications for rare earth element complexation with organic matter in natural waters

Science.gov (United States)

Tang, Jianwu; Johannesson, Karen H.

2010-12-01

The ability of organic matter as well as carbonate ions to extract rare earth elements (REEs) from sandy sediments of a Coastal Plain aquifer was investigated for unpurified organic matter from different sources (i.e., Mississippi River natural organic matter, Aldrich humic acid, Nordic aquatic fulvic acid, Suwannee River fulvic acid, and Suwannee River natural organic matter) and for extraction solutions containing weak (i.e., CH 3COO -) or strong (i.e., CO32-) ligands. The experimental results indicate that, in the absence of strong REE complexing ligands in solution, the amount of REEs released from the sand is small and the fractionation pattern of the released REEs appears to be controlled by the surface stability constants for REE sorption with Fe(III) oxides/oxyhydroxides. In the presence of strong solution complexing ligands, however, the amount and the fractionation pattern of the released REEs reflect the strength and variation of the stability constants of the dominant aqueous REE species across the REE series. The varying amount of REEs extracted by the different organic matter employed in the experiments indicates that organic matter from different sources has different complexing capacity for REEs. However, the fractionation pattern of REEs extracted by the various organic matter used in our experiments is remarkable consistent, being independent of the source and the concentration of organic matter used, as well as solution pH. Because natural aquifer sand and unpurified organic matter were used in our experiments, our experimental conditions are more broadly similar to natural systems than many previous laboratory experiments of REE-humic complexation that employed purified humic substances. Our results suggest that the REE loading effect on REE-humic complexation is negligible in natural waters as more abundant metal cations (e.g., Fe, Al) out-compete REEs for strong binding sites on organic matter. More specifically, our results indicate that REE

The complex initial reluctivity, permeability and susceptibility spectra of magnetic materials

Science.gov (United States)

Hamilton, N. C.

2015-03-01

The HF complex permeability spectrum of a magnetic material is deduced from the measured impedance spectrum, which is then normalized to a series permeability spectrum. However, this series permeability spectrum has previously been shown to correspond to a parallel magnetic circuit, which is not appropriate. Some of the implications of this truth are examined. This electric/magnetic duality has frustrated efforts to interpret the shape of the complex magnetic permeability spectra of materials, and has hindered the application of impedance spectroscopy to magnetic materials. In the presence of magnetic loss, the relationship between the relative magnetic permeability and the magnetic susceptibility is called into question. The use of reluctivity spectra for expressing magnetic material properties is advocated. The relative loss factor, tanδm/μi is shown to be an approximation for the imaginary part of the reluctivity. A single relaxation model for the initial reluctivity spectra of magnetic materials is presented, and its principles are applied to measurements of a high permeability ferrite. The results are presented as contour plots of the spectra as a function of temperature.

Modeling hemoglobin and hemoglobin:haptoglobin complex clearance in a non-rodent species–pharmacokinetic and therapeutic implications

OpenAIRE

Boretti, Felicitas S.; Baek, Jin Hyen; Palmer, Andre F.; Schaer, Dominik J.; Buehler, Paul W.

2014-01-01

Background: Haptoglobin (Hp) prevents hemoglobin (Hb) extravasation and attenuates Hb induced tissue oxidation and vasoconstriction. Small animal models such as mouse, rat and guinea pig appear to demonstrate proof-of-concept for Hb neutralization by Hp in diverse pre-clinical conditions. However, these species differ significantly from humans in the clearance of Hb:Hp and demonstrate long persistence of circulating Hb:Hp complexes. Objective: The focus of this study is to understand Hb:Hp...

Implicative Algebras | Kolluru | Momona Ethiopian Journal of Science

African Journals Online (AJOL)

In this paper we introduce the concept of implicative algebras which is an equivalent definition of lattice implication algebra of Xu (1993) and further we prove that it is a regular Autometrized Algebra. Further we remark that the binary operation → on lattice implicative algebra can never be associative. Keywords: Implicative ...

Complex dynamics and switching transients in periodically forced Filippov prey–predator system

International Nuclear Information System (INIS)

Tang, Guangyao; Qin, Wenjie; Tang, Sanyi

2014-01-01

Highlights: •We develop a Filippov prey–predator model with periodic forcing. •The sliding mode dynamics and its domain have been investigated. •The existence and stability of sliding periodic solution have been discussed. •The complex dynamics are addressed through bifurcation analyses. •Switching transients and their biological implications have been discussed. - Abstract: By employing threshold policy control (TPC) in combination with the definition of integrated pest management (IPM), a Filippov prey–predator model with periodic forcing has been proposed and studied, and the periodic forcing is affected by assuming a periodic variation in the intrinsic growth rate of the prey. This study aims to address how the periodic forcing and TPC affect the pest control. To do this, the sliding mode dynamics and sliding mode domain have been addressed firstly by using Utkin’s equivalent control method, and then the existence and stability of sliding periodic solution are investigated. Furthermore, the complex dynamics including multiple attractors coexistence, period adding sequences and chaotic solutions with respect to bifurcation parameters of forcing amplitude and economic threshold (ET) have been investigated numerically in more detail. Finally the switching transients associated with pest outbreaks and their biological implications have been discussed. Our results indicate that the sliding periodic solution could be globally stable, and consequently the prey or pest population can be controlled such that its density falls below the economic injury level (EIL). Moreover, the switching transients have both advantages and disadvantages concerning pest control, and the magnitude and frequency of switching transients depend on the initial values of both populations, forcing amplitude and ET

Ti(IV) and the Siderophore Desferrioxamine B: A Tight Complex Has Biological and Environmental Implications.

Science.gov (United States)

Jones, Kayleigh E; Batchler, Kathleen L; Zalouk, Célia; Valentine, Ann M

2017-02-06

The siderophore desferrioxamine B (DFOB) binds Ti(IV) tightly and precludes its hydrolytic precipitation under biologically and environmentally relevant conditions. This interaction of DFOB with Ti(IV) is investigated by using spectro-potentiometric and spectro-photometric titrations, mass spectrometry, isothermal titration calorimetry (ITC), and computational modeling. The data from pH 2-10 suggest two one-proton equilibria among three species, with one species predominating below pH 3.5, a second from pH 3.5 to 8, and a third above pH 8. The latter species is prone to slow hydrolytic precipitation. Electrospray mass spectrometry allowed the detection of [Ti(IV) (HDFOB)] 2+ and [Ti(DFOB)] + ; these species were assigned as the pH UV/vis-monitored competition with ethylenediaminetetraacetic acid (EDTA). Taking into consideration the available binding constant of Ti(IV) and EDTA, the data reveal values of log β 111 = 41.7, log β 110 = 38.1, and log β 11-1 = 30.1. The former value was supported by ITC, with the transfer of Ti(IV) from EDTA to DFOB determined to be both enthalpically and entropically favorable. Computational methods yielded a model of Ti-DFOB. The physiological and environmental implications of this tight interaction and the potential role of DFOB in solubilizing Ti(IV) are discussed.

Carbon monoxide migratory insertion - A comparison of cationic and neutral palladium(II) complexes

International Nuclear Information System (INIS)

Frankcombe, K.; Cavell, K.J.; Yates, B.F.; Knott, R.B.

1998-01-01

With the use of ANSTO's resources and expertise and with support from AINSE, we have carried out extensive computer modelling on the mechanism of the palladium catalysed carbonylation reaction, a process which is used industrially in the conversion of carbon monoxide into biodegradable polymers. In this project, experimental and theoretical work has focussed on using Pd(II) complexes containing pyridine carboxylate ligands (NC 5 H 4 COO ) to explore the fundamental mechanistic steps. The results for subsequent steps in the catalytic cycle are presented and their implication for the design of more efficient catalysts are discussed

Physics, nature and society a guide to order and complexity in our world

CERN Document Server

Marro, Joaquín

2014-01-01

This wide-ranging and accessible book serves as a fascinating guide to the strategies and concepts that help us understand the boundaries between physics, on the one hand, and sociology, economics, and biology on the other. From cooperation and criticality to flock dynamics and fractals, the author addresses many of the topics belonging to the broad theme of complexity. He chooses excellent examples (requiring no prior mathematical knowledge) to illuminate these ideas and their implications. The lively style and clear description of the relevant models will appeal both to novices and those with an existing knowledge of the field.

The Santa Izabel Complex, Gavião Block, Brazil: Components, geocronology, regional correlations and tectonic implications

Science.gov (United States)

Medeiros, Eder Luis Mathias; Cruz, Simone Cerqueira Pereira; Barbosa, Johildo Salomão Figueiredo; Paquette, Jean Louis; Peucat, Jean Jacques; Jesus, Silvandira dos Santos Góes Pereira de; Barbosa, Rafael Gordilho; Brito, Reinaldo Santana Correia de; Carneiro, Mauricio Antônio

2017-12-01

Cratons, as well as the basement of their marginal orogens, may represent important sites of research regarding the formation and evolution of Archean continental crusts. The Gavião Block is one of the oldest terranes in South America with rocks aged up to 3.6 Ga. Among the Archean units that outcrop in the southern sector of this block is the Santa Izabel Complex, which for the most part is located in the São Francisco Craton, close to its limit with the Araçuaí-West Congo Orogen. This complex has generally been described as comprising ortho- and paraderived rocks that were metamorphosed in high amphibolite facies. Studies in the southern region of this complex have shown the main components: (i) orthogneisses, whose protoliths are the Mesoarchean rocks of the Santa Izabel Magmatic Suite; and (iii) migmatites. and (iv) amphibolitic and metaultramafic enclaves. U-Pb studies (LA-ICPMS and SHRIMP) performed on zircons of the paleosome in metatexites and inherited zircons in migmatites indicate crystallization ages between 3091 ± 24 and 3136 ± 8 Ma for the rocks of the Santa Izabel Magmatic Suite. Inherited zircons aged ca. 3.4 Ga in paleosomes demonstrate the influence of older continental crust in the formation of these rocks. For the Caraguatai Magmatic Suite, the alignment of zircons and monazites suggests a crystallization age around 2.6 Ga. The Rhyacian migmatites were divided into metatexites and diatexites. Diatexites were divided into: (i) discontinuous boudinated early diatexites, which are parallel to stromatic metatexites, composing the gneissic banding. These rocks have diffuse metamorphic banding and features that suggest the action of mylonitization processes; and (ii) late diatexites, forming more continuous bodies, which truncate the gneissic banding. The migmatization occurred in two stages, with time interval between ca. 2.1 Ga and 2.07 Ga. The structural framework reveal the existence of four progressive Rhyacian deformation phases (Dn to Dn

A Straightforward Route to Tetrachloroauric Acid from Gold Metal and Molecular Chlorine for Nanoparticle Synthesis

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Shirin R. King

2015-08-01

Full Text Available Aqueous solutions of tetrachloroauric acid of high purity and stability were synthesised using the known reaction of gold metal with chlorine gas. The straightforward procedure developed here allows the resulting solution to be used directly for gold nanoparticle synthesis. The procedure involves bubbling chlorine gas through pure water containing a pellet of gold. The reaction is quantitative and progressed at a satisfactory rate at 50 °C. The gold(III chloride solutions produced by this method show no evidence of returning to metallic gold over at least twelve months. This procedure also provides a straightforward method to determine the concentration of the resulting solution using the initial mass of gold and volume of water.

Toroidal surface complexes of bacteriophage φ12 are responsible for host-cell attachment

International Nuclear Information System (INIS)

Leo-Macias, Alejandra; Katz, Garrett; Wei Hui; Alimova, Alexandra; Katz, A.; Rice, William J.; Diaz-Avalos, Ruben; Hu Guobin; Stokes, David L.; Gottlieb, Paul

2011-01-01

Cryo-electron tomography and subtomogram averaging are utilized to determine that the bacteriophage φ12, a member of the Cystoviridae family, contains surface complexes that are toroidal in shape, are composed of six globular domains with six-fold symmetry, and have a discrete density connecting them to the virus membrane-envelope surface. The lack of this kind of spike in a reassortant of φ12 demonstrates that the gene for the hexameric spike is located in φ12's medium length genome segment, likely to the P3 open reading frames which are the proteins involved in viral-host cell attachment. Based on this and on protein mass estimates derived from the obtained averaged structure, it is suggested that each of the globular domains is most likely composed of a total of four copies of P3a and/or P3c proteins. Our findings may have implications in the study of the evolution of the cystovirus species in regard to their host specificity. - Research Highlights: → Subtomogram averaging reveals enhanced detail of a φ12 cystovirus surface protein complex. → The surface protein complex has a toroidal shape and six-fold symmetry. → It is encoded by the medium-size genome segment. → The proteins of the surface complex most likely are one copy of P3a and three copies of P3c.

Bohmian mechanics with complex action: A new trajectory-based formulation of quantum mechanics

International Nuclear Information System (INIS)

Goldfarb, Yair; Degani, Ilan; Tannor, David J.

2006-01-01

In recent years there has been a resurgence of interest in Bohmian mechanics as a numerical tool because of its local dynamics, which suggest the possibility of significant computational advantages for the simulation of large quantum systems. However, closer inspection of the Bohmian formulation reveals that the nonlocality of quantum mechanics has not disappeared--it has simply been swept under the rug into the quantum force. In this paper we present a new formulation of Bohmian mechanics in which the quantum action, S, is taken to be complex. This leads to a single equation for complex S, and ultimately complex x and p but there is a reward for this complexification - a significantly higher degree of localization. The quantum force in the new approach vanishes for Gaussian wave packet dynamics, and its effect on barrier tunneling processes is orders of magnitude lower than that of the classical force. In fact, the current method is shown to be a rigorous extension of generalized Gaussian wave packet dynamics to give exact quantum mechanics. We demonstrate tunneling probabilities that are in virtually perfect agreement with the exact quantum mechanics down to 10 -7 calculated from strictly localized quantum trajectories that do not communicate with their neighbors. The new formulation may have significant implications for fundamental quantum mechanics, ranging from the interpretation of non-locality to measures of quantum complexity

Locating the source of diffusion in complex networks by time-reversal backward spreading

Science.gov (United States)

Shen, Zhesi; Cao, Shinan; Wang, Wen-Xu; Di, Zengru; Stanley, H. Eugene

2016-03-01

Locating the source that triggers a dynamical process is a fundamental but challenging problem in complex networks, ranging from epidemic spreading in society and on the Internet to cancer metastasis in the human body. An accurate localization of the source is inherently limited by our ability to simultaneously access the information of all nodes in a large-scale complex network. This thus raises two critical questions: how do we locate the source from incomplete information and can we achieve full localization of sources at any possible location from a given set of observable nodes. Here we develop a time-reversal backward spreading algorithm to locate the source of a diffusion-like process efficiently and propose a general locatability condition. We test the algorithm by employing epidemic spreading and consensus dynamics as typical dynamical processes and apply it to the H1N1 pandemic in China. We find that the sources can be precisely located in arbitrary networks insofar as the locatability condition is assured. Our tools greatly improve our ability to locate the source of diffusion in complex networks based on limited accessibility of nodal information. Moreover, they have implications for controlling a variety of dynamical processes taking place on complex networks, such as inhibiting epidemics, slowing the spread of rumors, pollution control, and environmental protection.

ComplexViewer: visualization of curated macromolecular complexes.

Science.gov (United States)

Combe, Colin W; Sivade, Marine Dumousseau; Hermjakob, Henning; Heimbach, Joshua; Meldal, Birgit H M; Micklem, Gos; Orchard, Sandra; Rappsilber, Juri

2017-11-15

Proteins frequently function as parts of complexes, assemblages of multiple proteins and other biomolecules, yet network visualizations usually only show proteins as parts of binary interactions. ComplexViewer visualizes interactions with more than two participants and thereby avoids the need to first expand these into multiple binary interactions. Furthermore, if binding regions between molecules are known then these can be displayed in the context of the larger complex. freely available under Apache version 2 license; EMBL-EBI Complex Portal: http://www.ebi.ac.uk/complexportal; Source code: https://github.com/MICommunity/ComplexViewer; Package: https://www.npmjs.com/package/complexviewer; http://biojs.io/d/complexviewer. Language: JavaScript; Web technology: Scalable Vector Graphics; Libraries: D3.js. colin.combe@ed.ac.uk or juri.rappsilber@ed.ac.uk. © The Author 2017. Published by Oxford University Press.

Preictal dynamics of EEG complexity in intracranially recorded epileptic seizure: a case report.

Science.gov (United States)

Bob, Petr; Roman, Robert; Svetlak, Miroslav; Kukleta, Miloslav; Chladek, Jan; Brazdil, Milan

2014-11-01

Recent findings suggest that neural complexity reflecting a number of independent processes in the brain may characterize typical changes during epileptic seizures and may enable to describe preictal dynamics. With respect to previously reported findings suggesting specific changes in neural complexity during preictal period, we have used measure of pointwise correlation dimension (PD2) as a sensitive indicator of nonstationary changes in complexity of the electroencephalogram (EEG) signal. Although this measure of complexity in epileptic patients was previously reported by Feucht et al (Applications of correlation dimension and pointwise dimension for non-linear topographical analysis of focal onset seizures. Med Biol Comput. 1999;37:208-217), it was not used to study changes in preictal dynamics. With this aim to study preictal changes of EEG complexity, we have examined signals from 11 multicontact depth (intracerebral) EEG electrodes located in 108 cortical and subcortical brain sites, and from 3 scalp EEG electrodes in a patient with intractable epilepsy, who underwent preoperative evaluation before epilepsy surgery. From those 108 EEG contacts, records related to 44 electrode contacts implanted into lesional structures and white matter were not included into the experimental analysis.The results show that in comparison to interictal period (at about 8-6 minutes before seizure onset), there was a statistically significant decrease in PD2 complexity in the preictal period at about 2 minutes before seizure onset in all 64 intracranial channels localized in various brain sites that were included into the analysis and in 3 scalp EEG channels as well. Presented results suggest that using PD2 in EEG analysis may have significant implications for research of preictal dynamics and prediction of epileptic seizures.

Towards structural studies of the old yellow enzyme homologue SYE4 from Shewanella oneidensis and its complexes at atomic resolution

International Nuclear Information System (INIS)

Elegheert, Jonathan; Hemel, Debbie van den; Dix, Ina; Stout, Jan; Van Beeumen, Jozef; Brigé, Ann; Savvides, Savvas N.

2009-01-01

Of the four old yellow enzyme homologues found in S. oneidensis, SYE4 is the homologue most implicated in resistance to oxidative stress. SYE4 was recombinantly expressed in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method. Shewanella oneidensis is an environmentally versatile Gram-negative γ-proteobacterium that is endowed with an unusually large proteome of redox proteins. Of the four old yellow enzyme (OYE) homologues found in S. oneidensis, SYE4 is the homologue most implicated in resistance to oxidative stress. SYE4 was recombinantly expressed in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method. The crystals belonged to the orthorhombic space group P2 1 2 1 2 1 and were moderately pseudo-merohedrally twinned, emulating a P422 metric symmetry. The native crystals of SYE4 were of exceptional diffraction quality and provided complete data to 1.10 Å resolution using synchrotron radiation, while crystals of the reduced enzyme and of the enzyme in complex with a wide range of ligands typically led to high-quality complete data sets to 1.30–1.60 Å resolution, thus providing a rare opportunity to dissect the structure–function relationships of a good-sized enzyme (40 kDa) at true atomic resolution. Here, the attainment of a number of experimental milestones in the crystallographic studies of SYE4 and its complexes are reported, including isolation of the elusive hydride–Meisenheimer complex

Highly divergent mitochondrial ATP synthase complexes in Tetrahymena thermophila.

Directory of Open Access Journals (Sweden)

Praveen Balabaskaran Nina

2010-07-01

substitute for the subunit a of the F(o sector. The absence of genes encoding orthologs of the novel subunits even in apicomplexans suggests that the Tetrahymena ATP synthase, despite core similarities, is a unique enzyme exhibiting dramatic differences compared to the conventional complexes found in metazoan, fungal, and plant mitochondria, as well as in prokaryotes. These findings have significant implications for the origins and evolution of a central player in bioenergetics.

Mutated PET117 causes complex IV deficiency and is associated with neurodevelopmental regression and medulla oblongata lesions.

Science.gov (United States)

Renkema, G H; Visser, G; Baertling, F; Wintjes, L T; Wolters, V M; van Montfrans, J; de Kort, G A P; Nikkels, P G J; van Hasselt, P M; van der Crabben, S N; Rodenburg, R J T

2017-06-01

The genetic basis of the many progressive, multi systemic, mitochondrial diseases that cause a lack of cellular ATP production is heterogeneous, with defects found both in the mitochondrial genome as well as in the nuclear genome. Many different mutations have been found in the genes encoding subunits of the enzyme complexes of the oxidative phosphorylation system. In addition, mutations in genes encoding proteins involved in the assembly of these complexes are known to cause mitochondrial disorders. Here we describe two sisters with a mitochondrial disease characterized by lesions in the medulla oblongata, as demonstrated by brain magnetic resonance imaging, and an isolated complex IV deficiency and reduced levels of individual complex IV subunits. Whole exome sequencing revealed a homozygous nonsense mutation resulting in a premature stop codon in the gene encoding Pet117, a small protein that has previously been predicted to be a complex IV assembly factor. PET117 has not been identified as a mitochondrial disease gene before. Lentiviral complementation of patient fibroblasts with wild-type PET117 restored the complex IV deficiency, proving that the gene defect is responsible for the complex IV deficiency in the patients, and indicating a pivotal role of this protein in the proper functioning of complex IV. Although previous studies had suggested a possible role of this protein in the insertion of copper into complex IV, studies in patient fibroblasts could not confirm this. This case presentation thus implicates mutations in PET117 as a novel cause of mitochondrial disease.

Genomic sequencing: assessing the health care system, policy, and big-data implications.

Science.gov (United States)

Phillips, Kathryn A; Trosman, Julia R; Kelley, Robin K; Pletcher, Mark J; Douglas, Michael P; Weldon, Christine B

2014-07-01

New genomic sequencing technologies enable the high-speed analysis of multiple genes simultaneously, including all of those in a person's genome. Sequencing is a prominent example of a "big data" technology because of the massive amount of information it produces and its complexity, diversity, and timeliness. Our objective in this article is to provide a policy primer on sequencing and illustrate how it can affect health care system and policy issues. Toward this end, we developed an easily applied classification of sequencing based on inputs, methods, and outputs. We used it to examine the implications of sequencing for three health care system and policy issues: making care more patient-centered, developing coverage and reimbursement policies, and assessing economic value. We conclude that sequencing has great promise but that policy challenges include how to optimize patient engagement as well as privacy, develop coverage policies that distinguish research from clinical uses and account for bioinformatics costs, and determine the economic value of sequencing through complex economic models that take into account multiple findings and downstream costs. Project HOPE—The People-to-People Health Foundation, Inc.

The neurobiology of uncertainty: implications for statistical learning.

Science.gov (United States)

Hasson, Uri

2017-01-05

The capacity for assessing the degree of uncertainty in the environment relies on estimating statistics of temporally unfolding inputs. This, in turn, allows calibration of predictive and bottom-up processing, and signalling changes in temporally unfolding environmental features. In the last decade, several studies have examined how the brain codes for and responds to input uncertainty. Initial neurobiological experiments implicated frontoparietal and hippocampal systems, based largely on paradigms that manipulated distributional features of visual stimuli. However, later work in the auditory domain pointed to different systems, whose activation profiles have interesting implications for computational and neurobiological models of statistical learning (SL). This review begins by briefly recapping the historical development of ideas pertaining to the sensitivity to uncertainty in temporally unfolding inputs. It then discusses several issues at the interface of studies of uncertainty and SL. Following, it presents several current treatments of the neurobiology of uncertainty and reviews recent findings that point to principles that serve as important constraints on future neurobiological theories of uncertainty, and relatedly, SL. This review suggests it may be useful to establish closer links between neurobiological research on uncertainty and SL, considering particularly mechanisms sensitive to local and global structure in inputs, the degree of input uncertainty, the complexity of the system generating the input, learning mechanisms that operate on different temporal scales and the use of learnt information for online prediction.This article is part of the themed issue 'New frontiers for statistical learning in the cognitive sciences'. © 2016 The Author(s).

The apical complex provides a regulated gateway for secretion of invasion factors in Toxoplasma.

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Nicholas J Katris

2014-04-01

Full Text Available The apical complex is the definitive cell structure of phylum Apicomplexa, and is the focus of the events of host cell penetration and the establishment of intracellular parasitism. Despite the importance of this structure, its molecular composition is relatively poorly known and few studies have experimentally tested its functions. We have characterized a novel Toxoplasma gondii protein, RNG2, that is located at the apical polar ring--the common structural element of apical complexes. During cell division, RNG2 is first recruited to centrosomes immediately after their duplication, confirming that assembly of the new apical complex commences as one of the earliest events of cell replication. RNG2 subsequently forms a ring, with the carboxy- and amino-termini anchored to the apical polar ring and mobile conoid, respectively, linking these two structures. Super-resolution microscopy resolves these two termini, and reveals that RNG2 orientation flips during invasion when the conoid is extruded. Inducible knockdown of RNG2 strongly inhibits host cell invasion. Consistent with this, secretion of micronemes is prevented in the absence of RNG2. This block, however, can be fully or partially overcome by exogenous stimulation of calcium or cGMP signaling pathways, respectively, implicating the apical complex directly in these signaling events. RNG2 demonstrates for the first time a role for the apical complex in controlling secretion of invasion factors in this important group of parasites.

A review of the health and economic implications of patent protection, with a specific focus on Thailand.

Science.gov (United States)

Yamabhai, Inthira; Smith, Richard D

2012-08-01

Although it has been two decades since the Thai Patent Act was amended to comply with the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS), there has been little emphasis given to assessing the implications of this amendment. The purpose of this review is to summarize the health and economic impact of patent protection, with a focus on the experience of Thailand. A review of national and international empirical evidence on the health and economic implications of patents from 1980 to 2009 was undertaken. The findings illustrate the role of patent protection in four areas: price, present access, future access, and international trade and investment. Forty-three empirical studies were found, three of which were from Thai databases. Patenting does increase price, although the size of effect differs according to the methodology and country. Although weakening patent rights could increase present access, evidence suggests that strengthening patenting may benefit future access; although this is based on complex assumptions and estimations. Moreover, while patent protection appears to have a positive impact on trade flow, the implication for foreign direct investment (FDI) is equivocal. Empirical studies in Thailand, and other similar countries, are rare, compromising the robustness and generalizability of conclusions. However, evidence does suggest that patenting presents a significant inter-temporal challenge in balancing aspects of current versus future access to technologies. This underlines the urgent need to prioritize health research resources to assess the wider implications of patent protection.

Unanticipated Mycobacterium tuberculosis complex culture inhibition by immune modulators, immune suppressants, a growth enhancer, and vitamins A and D: clinical implications.

Science.gov (United States)

Greenstein, Robert J; Su, Liya; Shahidi, Azra; Brown, William D; Clifford, Anya; Brown, Sheldon T

2014-09-01

The development of novel antibiotics to treat multidrug-resistant (MDR) tuberculosis is time-consuming and expensive. Multiple immune modulators, immune suppressants, anti-inflammatories, and growth enhancers, and vitamins A and D, inhibit Mycobacterium avium subspecies paratuberculosis (MAP) in culture. We studied the culture inhibition of Mycobacterium tuberculosis complex by these agents. Biosafety level two M. tuberculosis complex (ATCC 19015 and ATCC 25177) was studied in radiometric Bactec or MGIT culture. Agents evaluated included clofazimine, methotrexate, 6-mercaptopurine, cyclosporine A, rapamycin, tacrolimus, monensin, and vitamins A and D. All the agents mentioned above caused dose-dependent inhibition of the M. tuberculosis complex. There was no inhibition by the anti-inflammatory 5-aminosalicylic acid, which causes bacteriostatic inhibition of MAP. We conclude that, at a minimum, studies with virulent M. tuberculosis are indicated with the agents mentioned above, as well as with the thioamide 5-propothiouricil, which has previously been shown to inhibit the M. tuberculosis complex in culture. Our data additionally emphasize the importance of vitamins A and D in treating mycobacterial diseases. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

ANALOGUE AND DIGITAL MINDSETS: SOME IMPLICATIONS FOR INTERCULTURAL COMMUNICATION BETWEEN WESTERN AND EASTERN ORGANISATIONS

Directory of Open Access Journals (Sweden)

Hiroko Noma

2012-01-01

Full Text Available Globalising forces have given rise to new relationships between organisations operating in Eastern and Western cultural contexts. Despite the rich opportunities presented by globalisation, the literature indicates that managers are challenged by the complexity of intercultural communication. This scholarly paper discusses some implications of analogue and digital mindsets for the managers of organisations in which effective inter- cultural communication across Eastern and Western contexts is crucial. We do so by adopting a multidisciplinary approach to the phenomenon and suggesting how managers may capitalise on knowledge related to analogue and digital mindsets to foster creative and holistic approaches to communication.

From 'implications' to 'dimensions': science, medicine and ethics in society.

Science.gov (United States)

Pickersgill, Martyn D

2013-03-01

Much bioethical scholarship is concerned with the social, legal and philosophical implications of new and emerging science and medicine, as well as with the processes of research that under-gird these innovations. Science and technology studies (STS), and the related and interpenetrating disciplines of anthropology and sociology, have also explored what novel technoscience might imply for society, and how the social is constitutive of scientific knowledge and technological artefacts. More recently, social scientists have interrogated the emergence of ethical issues: they have documented how particular matters come to be regarded as in some way to do with 'ethics', and how this in turn enjoins particular types of social action. In this paper, I will discuss some of this and other STS (and STS-inflected) literature and reflect on how it might complement more 'traditional' modes of bioethical enquiry. I argue that STS might (1) cast new light on current bioethical issues, (2) direct the gaze of bioethicists towards matters that may previously have escaped their attention, and (3) indicate the import not only of the ethical implications of biomedical innovation, but also how these innovative and other processes feature ethics as a dimension of everyday laboratory and clinical work. In sum, engagements between STS and bioethics are increasingly important in order to understand and manage the complex dynamics between science, medicine and ethics in society.

High-level inhibition of mitochondrial complexes III and IV is required to increase glutamate release from the nerve terminal

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Kilbride Seán M

2011-07-01

Full Text Available Abstract Background The activities of mitochondrial complex III (ubiquinol-cytochrome c reductase, EC 1.10.2.2 and complex IV (cytochrome c oxidase EC 1.9.3.1 are reduced by 30-70% in Huntington's disease and Alzheimer's disease, respectively, and are associated with excitotoxic cell death in these disorders. In this study, we investigated the control that complexes III and complex IV exert on glutamate release from the isolated nerve terminal. Results Inhibition of complex III activity by 60-90% was necessary for a major increase in the rate of Ca2+-independent glutamate release to occur from isolated nerve terminals (synaptosomes depolarized with 4-aminopyridine or KCl. Similarly, an 85-90% inhibition of complex IV activity was required before a major increase in the rate of Ca2+-independent glutamate release from depolarized synaptosomes was observed. Inhibition of complex III and IV activities by ~ 60% and above was required before rates of glutamate efflux from polarized synaptosomes were increased. Conclusions These results suggest that nerve terminal mitochondria possess high reserves of complex III and IV activity and that high inhibition thresholds must be reached before excess glutamate is released from the nerve terminal. The implications of the results in the context of the relationship between electron transport chain enzyme deficiencies and excitotoxicity in neurodegenerative disorders are discussed.

High-level inhibition of mitochondrial complexes III and IV is required to increase glutamate release from the nerve terminal

LENUS (Irish Health Repository)

Kilbride, Sean M

2011-07-26

Abstract Background The activities of mitochondrial complex III (ubiquinol-cytochrome c reductase, EC 1.10.2.2) and complex IV (cytochrome c oxidase EC 1.9.3.1) are reduced by 30-70% in Huntington\\'s disease and Alzheimer\\'s disease, respectively, and are associated with excitotoxic cell death in these disorders. In this study, we investigated the control that complexes III and complex IV exert on glutamate release from the isolated nerve terminal. Results Inhibition of complex III activity by 60-90% was necessary for a major increase in the rate of Ca2+-independent glutamate release to occur from isolated nerve terminals (synaptosomes) depolarized with 4-aminopyridine or KCl. Similarly, an 85-90% inhibition of complex IV activity was required before a major increase in the rate of Ca2+-independent glutamate release from depolarized synaptosomes was observed. Inhibition of complex III and IV activities by ~ 60% and above was required before rates of glutamate efflux from polarized synaptosomes were increased. Conclusions These results suggest that nerve terminal mitochondria possess high reserves of complex III and IV activity and that high inhibition thresholds must be reached before excess glutamate is released from the nerve terminal. The implications of the results in the context of the relationship between electron transport chain enzyme deficiencies and excitotoxicity in neurodegenerative disorders are discussed.

Differential Effects of Munc18s on Multiple Degranulation-Relevant Trans-SNARE Complexes.

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Hao Xu

Full Text Available Mast cell exocytosis, which includes compound degranulation and vesicle-associated piecemeal degranulation, requires multiple Q- and R- SNAREs. It is not clear how these SNAREs pair to form functional trans-SNARE complexes and how these trans-SNARE complexes are selectively regulated for fusion. Here we undertake a comprehensive examination of the capacity of two Q-SNARE subcomplexes (syntaxin3/SNAP-23 and syntaxin4/SNAP-23 to form fusogenic trans-SNARE complexes with each of the four granule-borne R-SNAREs (VAMP2, 3, 7, 8. We report the identification of at least six distinct trans-SNARE complexes under enhanced tethering conditions: i VAMP2/syntaxin3/SNAP-23, ii VAMP2/syntaxin4/SNAP-23, iii VAMP3/syntaxin3/SNAP-23, iv VAMP3/syntaxin4/SNAP-23, v VAMP8/syntaxin3/SNAP-23, and vi VAMP8/syntaxin4/SNAP-23. We show for the first time that Munc18a operates synergistically with SNAP-23-based non-neuronal SNARE complexes (i to iv in lipid mixing, in contrast to Munc18b and c, which exhibit no positive effect on any SNARE combination tested. Pre-incubation with Munc18a renders the SNARE-dependent fusion reactions insensitive to the otherwise inhibitory R-SNARE cytoplasmic domains, suggesting a protective role of Munc18a for its cognate SNAREs. Our findings substantiate the recently discovered but unexpected requirement for Munc18a in mast cell exocytosis, and implicate post-translational modifications in Munc18b/c activation.

Synchronization in node of complex networks consist of complex chaotic system

Energy Technology Data Exchange (ETDEWEB)

Wei, Qiang, E-mail: qiangweibeihua@163.com [Beihua University computer and technology College, BeiHua University, Jilin, 132021, Jilin (China); Digital Images Processing Institute of Beihua University, BeiHua University, Jilin, 132011, Jilin (China); Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, 116024 (China); Xie, Cheng-jun [Beihua University computer and technology College, BeiHua University, Jilin, 132021, Jilin (China); Digital Images Processing Institute of Beihua University, BeiHua University, Jilin, 132011, Jilin (China); Liu, Hong-jun [School of Information Engineering, Weifang Vocational College, Weifang, 261041 (China); Li, Yan-hui [The Library, Weifang Vocational College, Weifang, 261041 (China)

2014-07-15

A new synchronization method is investigated for node of complex networks consists of complex chaotic system. When complex networks realize synchronization, different component of complex state variable synchronize up to different scaling complex function by a designed complex feedback controller. This paper change synchronization scaling function from real field to complex field for synchronization in node of complex networks with complex chaotic system. Synchronization in constant delay and time-varying coupling delay complex networks are investigated, respectively. Numerical simulations are provided to show the effectiveness of the proposed method.

Time scales of supercooled water and implications for reversible polyamorphism

Science.gov (United States)

Limmer, David T.; Chandler, David

2015-09-01

Deeply supercooled water exhibits complex dynamics with large density fluctuations, ice coarsening and characteristic time scales extending from picoseconds to milliseconds. Here, we discuss implications of these time scales as they pertain to two-phase coexistence and to molecular simulations of supercooled water. Specifically, we argue that it is possible to discount liquid-liquid criticality because the time scales imply that correlation lengths for such behaviour would be bounded by no more than a few nanometres. Similarly, it is possible to discount two-liquid coexistence because the time scales imply a bounded interfacial free energy that cannot grow in proportion to a macroscopic surface area. From time scales alone, therefore, we see that coexisting domains of differing density in supercooled water can be no more than nanoscale transient fluctuations.

Consumer knowledge and its implications for aspects of consumer purchasing behaviour in the case of information-intensive products

OpenAIRE

Vigar-Ellis, Debbie

2016-01-01

The purpose of this research was to better understand consumer knowledge, its constituents, antecedents and consequences or implications for other consumer behaviours so as to assist wine marketers and marketers of other information-intensive products with their marketing strategy development.  Wine is a complex product difficult for consumers to evaluate particularly prior to purchase but it is also a difficult product for marketers.  Wine has a very large number of both intrinsic and extrin...

Movement patterns of seaward migrating European eel (Anguilla anguilla) at a complex of riverine barriers: implications for conservation

DEFF Research Database (Denmark)

Piper, Adam T.; Svendsen, Jon Christian; Wright, Rosalind M.

2017-01-01

, this is currently lacking for many species. Employing high-resolution positioning telemetry, this study examined movements of downstream migrating adult European eel, Anguilla anguilla, as they encountered a complex of water control structures in one location on the River Stour, southern England. The distribution...

What is in a name? Understanding the implications of participant terminology.

Science.gov (United States)

Bibace, Roger; Clegg, Joshua W; Valsiner, Jaan

2009-03-01

The authors discuss the history of research terminology in American psychology with respect to the various labels given to those upon whom we conduct research ("observer"-"subject"-"participant"-"client"). This history is supplemented with an analysis of participant terminology in APA manuals from four historical eras, from the 1950s to the present. The general trend in participant terminology reflects the overall trends in American psychology, beginning with a complex lexicon that admitted both the passive and the active research participant, followed by a dominance of the passive term 'subject' and ending with the terminological ambiguity and multiplicity reflected in contemporary psychology. This selective history serves to contextualize a discussion of the meaning, functions, and implications of the transformations in, and debates over, participant terminology.

Implication of the changing concept of genes on plant breeder’s work

Directory of Open Access Journals (Sweden)

Marco Aurélio D. Dias

2011-01-01

Full Text Available The recent genome sequencing of some species has accumulated evidence that for a large number of traits, thecontrol and action of genes are far more complex than previously thought. This article discusses possible implications of newinsights into the gene concept on the work of plant breeders. Apparently, the successful application of biotechnological techniques is not as simple as once assumed. The evident changes in the available concept of genes confirmed what the past experience had shown,i.e, selection should focus on the phenotype, under the same conditions as the plant is to be cultivated in. Advanced vocationaltraining of plant breeders must be continuously maintained, focusing on phenotype-based selection in as accurate as possibleexperiments.

On some practical implications of the recent EU-directive on radiation protection

International Nuclear Information System (INIS)

Tschurlovits, M

1998-01-01

The following practical implications of the EU 96 directive on radiation protection in Austria are discussed: Quantitative justification and optimization of the recent standards is needed. The reduction of the annual dose limit to 20 mSv will affect a very small percentage of the persons subject to monitoring. The reduction of dose limits in external exposure of the population will not be dramatic at all. The model used to set up limits for internal exposure was changed to single intake; this implies some changes in design and monitoring. The deletion of convenient figures for 'unknown' radionuclides will make environmental and release monitoring more complex without gaining a higher level of protection. (A.K.)

Dorso-medial and ventro-lateral functional specialization of the human retrosplenial complex in spatial updating and orienting.

Science.gov (United States)

Burles, Ford; Slone, Edward; Iaria, Giuseppe

2017-04-01

The retrosplenial complex is a region within the posterior cingulate cortex implicated in spatial navigation. Here, we investigated the functional specialization of this large and anatomically heterogeneous region using fMRI and resting-state functional connectivity combined with a spatial task with distinct phases of spatial 'updating' (i.e., integrating and maintaining object locations in memory during spatial displacement) and 'orienting' (i.e., recalling unseen locations from current position in space). Both spatial 'updating' and 'orienting' produced bilateral activity in the retrosplenial complex, among other areas. However, spatial 'updating' produced slightly greater activity in ventro-lateral portions, of the retrosplenial complex, whereas spatial 'orienting' produced greater activity in a more dorsal and medial portion of it (both regions localized along the parieto-occipital fissure). At rest, both ventro-lateral and dorso-medial subregions of the retrosplenial complex were functionally connected to the hippocampus and parahippocampus, regions both involved in spatial orientation and navigation. However, the ventro-lateral subregion of the retrosplenial complex displayed more positive functional connectivity with ventral occipital and temporal object recognition regions, whereas the dorso-medial subregion activity was more correlated to dorsal activity and frontal activity, as well as negatively correlated with more ventral parietal structures. These findings provide evidence for a dorso-medial to ventro-lateral functional specialization within the human retrosplenial complex that may shed more light on the complex neural mechanisms underlying spatial orientation and navigation in humans.

Shaping meiotic chromosomes with SUMO: a feedback loop controls the assembly of the synaptonemal complex in budding yeast

Directory of Open Access Journals (Sweden)

Hideo Tsubouchi

2016-02-01

Full Text Available The synaptonemal complex (SC is a meiosis-specific chromosomal structure in which homologous chromosomes are intimately linked through arrays of specialized proteins called transverse filaments (TF. Widely conserved in eukaryote meiosis, the SC forms during prophase I and is essential for accurate segregation of homologous chromosomes at meiosis I. However, the basic mechanism overlooking formation and regulation of the SC has been poorly understood. By using the budding yeast Saccharomyces cerevisiae, we recently showed that SC formation is controlled through the attachment of multiple molecules of small ubiquitin-like modifier (SUMO to a regulator of TF assembly. Intriguingly, this SUMOylation is activated by TF, implicating the involvement of a positive feedback loop in the control of SC assembly. We discuss the implication of this finding and possible involvement of a similar mechanism in regulating other processes.

Learning without experience: Understanding the strategic implications of deregulation and competition in the electricity industry

Energy Technology Data Exchange (ETDEWEB)

Lomi, A. [School of Economics, University of Bologna, Bologna (Italy); Larsen, E.R. [Dept. of Managements Systems and Information, City University Business School, London (United Kingdom)

1998-11-01

As deregulation of the electricity industry continues to gain momentum around the world, electricity companies face unprecedented challenges. Competitive complexity and intensity will increase substantially as deregulated companies find themselves competing in new industries, with new rules, against unfamiliar competitors - and without any history to learn from. We describe the different kinds of strategic issues that newly deregulated utility companies are facing, and the risks that strategic issues implicate. We identify a number of problems induced by experiential learning under conditions of competence-destroying change, and we illustrate ways in which companies can activate history-independent learning processes. We suggest that Micro worlds - a new generation of computer-based learning environments made possible by conceptual and technological progress in the fields of system dynamics and systems thinking - are particularly appropriate tools to accelerate and enhance organizational and managerial learning under conditions of increased competitive complexity. (au)

Prime implicants in dynamic reliability analysis

International Nuclear Information System (INIS)

Tyrväinen, Tero

2016-01-01

This paper develops an improved definition of a prime implicant for the needs of dynamic reliability analysis. Reliability analyses often aim to identify minimal cut sets or prime implicants, which are minimal conditions that cause an undesired top event, such as a system's failure. Dynamic reliability analysis methods take the time-dependent behaviour of a system into account. This means that the state of a component can change in the analysed time frame and prime implicants can include the failure of a component at different time points. There can also be dynamic constraints on a component's behaviour. For example, a component can be non-repairable in the given time frame. If a non-repairable component needs to be failed at a certain time point to cause the top event, we consider that the condition that it is failed at the latest possible time point is minimal, and the condition in which it fails earlier non-minimal. The traditional definition of a prime implicant does not account for this type of time-related minimality. In this paper, a new definition is introduced and illustrated using a dynamic flowgraph methodology model. - Highlights: • A new definition of a prime implicant is developed for dynamic reliability analysis. • The new definition takes time-related minimality into account. • The new definition is needed in dynamic flowgraph methodology. • Results can be represented by a smaller number of prime implicants.

Generalized Combination Complex Synchronization for Fractional-Order Chaotic Complex Systems

Directory of Open Access Journals (Sweden)

Cuimei Jiang

2015-07-01

Full Text Available Based on two fractional-order chaotic complex drive systems and one fractional-order chaotic complex response system with different dimensions, we propose generalized combination complex synchronization. In this new synchronization scheme, there are two complex scaling matrices that are non-square matrices. On the basis of the stability theory of fractional-order linear systems, we design a general controller via active control. Additionally, by virtue of two complex scaling matrices, generalized combination complex synchronization between fractional-order chaotic complex systems and real systems is investigated. Finally, three typical examples are given to demonstrate the effectiveness and feasibility of the schemes.

Energetic Surface Smoothing of Complex Metal-Oxide Thin Films

International Nuclear Information System (INIS)

Willmott, P.R.; Herger, R.; Schlepuetz, C.M.; Martoccia, D.; Patterson, B.D.

2006-01-01

A novel energetic smoothing mechanism in the growth of complex metal-oxide thin films is reported from in situ kinetic studies of pulsed laser deposition of La 1-x Sr x MnO 3 on SrTiO 3 , using x-ray reflectivity. Below 50% monolayer coverage, prompt insertion of energetic impinging species into small-diameter islands causes them to break up to form daughter islands. This smoothing mechanism therefore inhibits the formation of large-diameter 2D islands and the seeding of 3D growth. Above 50% coverage, islands begin to coalesce and their breakup is thereby suppressed. The energy of the incident flux is instead rechanneled into enhanced surface diffusion, which leads to an increase in the effective surface temperature of ΔT≅500 K. These results have important implications on optimal conditions for nanoscale device fabrication using these materials

THE RESPIRATORY SUBSTRATE RHODOQUINOL INDUCES Q-CYCLE BYPASS REACTIONS IN THE YEAST CYTOCHROME bc1 COMPLEX - MECHANISTIC AND PHYSIOLOGICAL IMPLICATIONS

International Nuclear Information System (INIS)

Cape, Jonathan L.; Strahan, Jeff R.; Lenaeus, Michael J.; Yuknis, Brook A.; Le, Trieu T.; Shepherd, Jennifer; Bowman, Michael K.; Kramer, David M.

2005-01-01

The mitochondrial cytochrome bc1 complex catalyzes the transfer of electrons from ubiquinol to cyt c, while generating a proton motive force for ATP synthesis, via the ''Qcycle'' mechanism. Under certain conditions, electron flow through the Q-cycle is blocked at the level of a reactive intermediate in the quinol oxidase site of the enzyme, resulting in ''bypass reactions'', some of which lead to superoxide production. Using analogs of the respiratory substrates, ubiquinol-3 and rhodoquinol-3, we show that the relative rates of Q-cycle bypass reactions in the Saccharomyces cerevisiae cyt bc1 complex are highly dependent, by a factor of up to one hundred-fold, on the properties of the substrate quinol. Our results suggest that the rate of Q-cycle bypass reactions is dependent on the steady state concentration of reactive intermediates produced at the quinol oxidase site of the enzyme. We conclude that normal operation of the Q-cycle requires a fairly narrow window of redox potentials, with respect to the quinol substrate, to allow normal turnover of the complex while preventing potentially damaging bypass reactions

A relativistic density functional study of uranyl hydrolysis and complexation by carboxylic acids in aqueous solution

International Nuclear Information System (INIS)

Ray, Rupashree Shyama

2009-01-01

In this work, the complexation of uranium in its most stable oxidation state VI in aqueous solution was studied computationally, within the framework of density functional (DF) theory. The thesis is divided into the following parts: Chapter 2 briefly summarizes the relevant general aspects of actinide chemistry and then focuses on actinide environmental chemistry. Experimental results on hydrolysis, actinide complexation by carboxylic acids, and humic substances are presented to establish a background for the subsequent discussion. Chapter 3 describes the computational method used in this work and the relevant features of the parallel quantum chemistry code PARAGAUSS employed. First, the most relevant basics of the applied density functional approach are presented focusing on relativistic effects. Then, the treatment of solvent effects, essential for an adequate modeling of actinide species in aqueous solution, will be introduced. At the end of this chapter, computational parameters and procedures will be summarized. Chapter 4 presents the computational results including a comparison to available experimental data. In the beginning, the mononuclear hydrolysis product of UO_2"2"+, [UO_2OH]"+, will be discussed. The second part deals with actinide complexation by carboxylate ligands. First of all the coordination number for uranylacetate will be discussed with respect to implications for the complexation of actinides by humic substances followed by the uranyl complexation of aromatic carboxylic acids in comparison to earlier results for aliphatic ones. In the end, the ternary uranyl-hydroxo-acetate are discussed, as models of uranyl humate complexation at ambient condition.

Complexity explained

CERN Document Server

Erdi, Peter

2008-01-01

This book explains why complex systems research is important in understanding the structure, function and dynamics of complex natural and social phenomena. Readers will learn the basic concepts and methods of complex system research.

Regulation of adeno-associated virus DNA replication by the cellular TAF-I/set complex.

Science.gov (United States)

Pegoraro, Gianluca; Marcello, Alessandro; Myers, Michael P; Giacca, Mauro

2006-07-01

The Rep proteins of the adeno-associated virus (AAV) are required for viral replication in the presence of adenovirus helper functions and as yet poorly characterized cellular factors. In an attempt to identify such factors, we purified Flag-Rep68-interacting proteins from human cell lysates. Several polypeptides were identified by mass spectrometry, among which was ANP32B, a member of the acidic nuclear protein 32 family which takes part in the formation of the template-activating factor I/Set oncoprotein (TAF-I/Set) complex. The N terminus of Rep was found to specifically bind the acidic domain of ANP32B; through this interaction, Rep was also able to recruit other members of the TAF-I/Set complex, including the ANP32A protein and the histone chaperone TAF-I/Set. Further experiments revealed that silencing of ANP32A and ANP32B inhibited AAV replication, while overexpression of all of the components of the TAF-I/Set complex increased de novo AAV DNA synthesis in permissive cells. Besides being the first indication that the TAF-I/Set complex participates in wild-type AAV replication, these findings have important implications for the generation of recombinant AAV vectors since overexpression of the TAF-I/Set components was found to markedly increase viral vector production.

The social context of career choice among millennial nurses: implications for interprofessional practice.

Science.gov (United States)

Price, Sheri; McGillis Hall, Linda; Angus, Jan; Peter, Elizabeth

2013-11-01

Health human resource and workforce planning is a global priority. Given the critical nursing shortage, and the fact that nurses are the largest group of healthcare providers, health workforce planning must focus on strategies to enhance both recruitment and retention of nurses. Understanding early socialization to career choice can provide insight into professional perceptions and expectations that have implications for recruitment, retention and interprofessional collaboration. This interpretive narrative inquiry utilized Polkinghorne's theory of narrative emplotment to understand the career choice experiences of 12 millennial nurses (born between 1980 and 2000) in Eastern Canada. Participants were interviewed twice, face-to-face, 4 to 6 weeks apart prior to commencing their nursing program. The narratives present career choice as a complex consideration of social positioning. The findings provide insight into how nursing is perceived to be positioned in relation to medicine and how the participants struggled to locate themselves within this social hierarchy. Implications of this research highlight the need to ensure that recruitment messaging and organizational policies promote interprofessional collaboration from the onset of choosing a career in the health professions. Early professional socialization strategies during recruitment and education can enhance future collaboration between the health professions.

Genetic architecture of HIV-1 genes circulating in north India & their functional implications.

Science.gov (United States)

Neogi, Ujjwal; Sood, Vikas; Ronsard, Larence; Singh, Jyotsna; Lata, Sneh; Ramachandran, V G; Das, S; Wanchu, Ajay; Banerjea, Akhil C

2011-12-01

This review presents data on genetic and functional analysis of some of the HIV-1 genes derived from HIV-1 infected individuals from north India (Delhi, Punjab and Chandigarh). We found evidence of novel B/C recombinants in HIV-1 LTR region showing relatedness to China/Myanmar with 3 copies of Nfκb sites; B/C/D mosaic genomes for HIV-1 Vpr and novel B/C Tat. We reported appearance of a complex recombinant form CRF_02AG of HIV-1 envelope sequences which is predominantly found in Central/Western Africa. Also one Indian HIV-1 envelope subtype C sequence suggested exclusive CXCR4 co-receptor usage. This extensive recombination, which is observed in about 10 per cent HIV-1 infected individuals in the Vpr genes, resulted in remarkably altered functions when compared with prototype subtype B Vpr. The Vpu C was found to be more potent in causing apoptosis when compared with Vpu B when analyzed for subG1 DNA content. The functional implications of these changes as well as in other genes of HIV-1 are discussed in detail with possible implications for subtype-specific pathogenesis highlighted.

L'analyse implicative bayésienne multivariée d'un questionnaire binaire : quasi-implications et treillis de Galois simplifié

OpenAIRE

Bernard, Jean-Marc; Poitrenaud, Sébastien

2006-01-01

We propose a new method for simplifying the Galois lattice associated to a binary questionnaire (n units classified according to q binary questions). The method consists in weakening the implications borne by the lattice into quasi-implications. At the descriptive level, the method involves a new measure for quasi-implications (the "multivariate implicative index") which satisfies some requirements of invariance by logical equivalence. At the inductive level, uncertainty about the patterns' t...

A pp32-retinoblastoma protein complex modulates androgen receptor-mediated transcription and associates with components of the splicing machinery

International Nuclear Information System (INIS)

Adegbola, Onikepe; Pasternack, Gary R.

2005-01-01

We have previously shown pp32 and the retinoblastoma protein interact. pp32 and the retinoblastoma protein are nuclear receptor transcriptional coregulators: the retinoblastoma protein is a coactivator for androgen receptor, the major regulator of prostate cancer growth, while pp32, which is highly expressed in prostate cancer, is a corepressor of the estrogen receptor. We now show pp32 increases androgen receptor-mediated transcription and the retinoblastoma protein modulates this activity. Using affinity purification and mass spectrometry, we identify members of the pp32-retinoblastoma protein complex as PSF and nonO/p54nrb, proteins implicated in coordinate regulation of nuclear receptor-mediated transcription and splicing. We show that the pp32-retinoblastoma protein complex is modulated during TPA-induced K562 differentiation. Present evidence suggests that nuclear receptors assemble multiprotein complexes to coordinately regulate transcription and mRNA processing. Our results suggest that pp32 and the retinoblastoma protein may be part of a multiprotein complex that coordinately regulates nuclear receptor-mediated transcription and mRNA processing

[Clinical implications of polycystic ovary syndrome].

Science.gov (United States)

Dravecká, Ingrid

Polycystic ovary syndrome (PCOS) is a heterogeneous and complex endocrine disease which among the female population belongs to the most widespread endocrinopathies and it is the most frequent cause of hyperthyroidism, anticoagulation and infertility. Insulin resistance is one of the important diabetology factors impacting hyperglycaemia in a majority of women with PCOS (60-80 %). Clinical expressions of PCOS include reproduction disorders, metabolic characteristics and psychological implications. Reproduction disorders include hyperthyroidism, menstruation cycle disorders, infertility and pregnancy complications as well as early abortions, gestational diabetes and pregnancy induced hypertension. Long-term metabolic risks of PCOS include type 2 diabetes mellitus, dyslipidemia, arterial hypertension and endothelial dysfunction. The available data confirms higher incidence of cardiovascular diseases in women with PCOS. In particular among obese women PCOS is more frequently associated with non-alcoholic hepatic steatosis, sleep apnoea syndrome and endometrial cancer. The literature includes some controversial data about the relationship between PCOS and autoimmunity. Women with PCOS are more prone to suffer from insufficient confidence with higher incidence of anxiety, depression, bipolar disorder and eating disorders. autoimmunity - diabetes mellitus - pregnancy - insulin resistance - metabolic syndrome - menstrual disorders - polycystic ovary syndrome.

Cloud chamber experiments on the origin of ice crystal complexity in cirrus clouds

Directory of Open Access Journals (Sweden)

M. Schnaiter

2016-04-01

Full Text Available This study reports on the origin of small-scale ice crystal complexity and its influence on the angular light scattering properties of cirrus clouds. Cloud simulation experiments were conducted at the AIDA (Aerosol Interactions and Dynamics in the Atmosphere cloud chamber of the Karlsruhe Institute of Technology (KIT. A new experimental procedure was applied to grow and sublimate ice particles at defined super- and subsaturated ice conditions and for temperatures in the −40 to −60 °C range. The experiments were performed for ice clouds generated via homogeneous and heterogeneous initial nucleation. Small-scale ice crystal complexity was deduced from measurements of spatially resolved single particle light scattering patterns by the latest version of the Small Ice Detector (SID-3. It was found that a high crystal complexity dominates the microphysics of the simulated clouds and the degree of this complexity is dependent on the available water vapor during the crystal growth. Indications were found that the small-scale crystal complexity is influenced by unfrozen H2SO4 / H2O residuals in the case of homogeneous initial ice nucleation. Angular light scattering functions of the simulated ice clouds were measured by the two currently available airborne polar nephelometers: the polar nephelometer (PN probe of Laboratoire de Métérologie et Physique (LaMP and the Particle Habit Imaging and Polar Scattering (PHIPS-HALO probe of KIT. The measured scattering functions are featureless and flat in the side and backward scattering directions. It was found that these functions have a rather low sensitivity to the small-scale crystal complexity for ice clouds that were grown under typical atmospheric conditions. These results have implications for the microphysical properties of cirrus clouds and for the radiative transfer through these clouds.

On Measuring the Complexity of Networks: Kolmogorov Complexity versus Entropy

Directory of Open Access Journals (Sweden)

Mikołaj Morzy

2017-01-01

Full Text Available One of the most popular methods of estimating the complexity of networks is to measure the entropy of network invariants, such as adjacency matrices or degree sequences. Unfortunately, entropy and all entropy-based information-theoretic measures have several vulnerabilities. These measures neither are independent of a particular representation of the network nor can capture the properties of the generative process, which produces the network. Instead, we advocate the use of the algorithmic entropy as the basis for complexity definition for networks. Algorithmic entropy (also known as Kolmogorov complexity or K-complexity for short evaluates the complexity of the description required for a lossless recreation of the network. This measure is not affected by a particular choice of network features and it does not depend on the method of network representation. We perform experiments on Shannon entropy and K-complexity for gradually evolving networks. The results of these experiments point to K-complexity as the more robust and reliable measure of network complexity. The original contribution of the paper includes the introduction of several new entropy-deceiving networks and the empirical comparison of entropy and K-complexity as fundamental quantities for constructing complexity measures for networks.

Locking of intrinsic angular momentum in collision complexes

International Nuclear Information System (INIS)

Berengolts, Alexander.

1995-04-01

A concept of locking of the intrinsic angular momentum of a fragment of a collision complex to a body-fixed axis is widely used in the description of heavy-particle dynamics. The aim of this work is to provide a semiclassical description of the locking phenomenon which occur in diatomic and three atomic collision complexes. The first part of this work is devoted to the semiclassical study of the locking of the electronic angular momentum that occurs in slow collisions of two atoms, one in the spherically symmetric state and the other in state with j= 1. Here we calculate explicitly the complete locking matrix for different types of interatomic interactions. The elements of this matrix directly enter into the semiclassical expression for the different cross sections of polarized atoms. Limitations to the notion of the the locking radius and slipping probability are discussed in connection with the steepness of the interaction. Numerical calculations confirm analytical result: the optimal criterion for determination of the locking radius is a condition for the accumulated phase difference between two molecular states. Analytical expressions are suggested for the locking angle and the slipping probability. Implication of the locking approximation for calculation of the quasiclassical scattering matrix is discussed. The second part considers the locking of the rotational angular momentum of a diatom in the decomposition of a triatomic complexes. We discuss here cases J = 1,2,3 and 4, but restrict ourselves to calculation of the so-called dynamic orientation of the diatomic fragment. The letter represents one of the characteristics of the locking matrix which in principle can be measured experimentally. The orientation is created as a result of the interplay between the adiabatic interaction in the atom- diatom exit channel and the rotationally non adiabatic coupling in the perturbed rotor region

Mutations in genes encoding condensin complex proteins cause microcephaly through decatenation failure at mitosis.

Science.gov (United States)

Martin, Carol-Anne; Murray, Jennie E; Carroll, Paula; Leitch, Andrea; Mackenzie, Karen J; Halachev, Mihail; Fetit, Ahmed E; Keith, Charlotte; Bicknell, Louise S; Fluteau, Adeline; Gautier, Philippe; Hall, Emma A; Joss, Shelagh; Soares, Gabriela; Silva, João; Bober, Michael B; Duker, Angela; Wise, Carol A; Quigley, Alan J; Phadke, Shubha R; Wood, Andrew J; Vagnarelli, Paola; Jackson, Andrew P

2016-10-01

Compaction of chromosomes is essential for accurate segregation of the genome during mitosis. In vertebrates, two condensin complexes ensure timely chromosome condensation, sister chromatid disentanglement, and maintenance of mitotic chromosome structure. Here, we report that biallelic mutations in NCAPD2, NCAPH, or NCAPD3, encoding subunits of these complexes, cause microcephaly. In addition, hypomorphic Ncaph2 mice have significantly reduced brain size, with frequent anaphase chromatin bridge formation observed in apical neural progenitors during neurogenesis. Such DNA bridges also arise in condensin-deficient patient cells, where they are the consequence of failed sister chromatid disentanglement during chromosome compaction. This results in chromosome segregation errors, leading to micronucleus formation and increased aneuploidy in daughter cells. These findings establish "condensinopathies" as microcephalic disorders, with decatenation failure as an additional disease mechanism for microcephaly, implicating mitotic chromosome condensation as a key process ensuring mammalian cerebral cortex size. © 2016 Martin et al.; Published by Cold Spring Harbor Laboratory Press.

Complex dynamical invariants for two-dimensional complex potentials

Indian Academy of Sciences (India)

Abstract. Complex dynamical invariants are searched out for two-dimensional complex poten- tials using rationalization method within the framework of an extended complex phase space characterized by x = x1 + ip3, y = x2 + ip4, px = p1 + ix3, py = p2 + ix4. It is found that the cubic oscillator and shifted harmonic oscillator ...

Complex Fuzzy Set-Valued Complex Fuzzy Measures and Their Properties

Science.gov (United States)

Ma, Shengquan; Li, Shenggang

2014-01-01

Let F*(K) be the set of all fuzzy complex numbers. In this paper some classical and measure-theoretical notions are extended to the case of complex fuzzy sets. They are fuzzy complex number-valued distance on F*(K), fuzzy complex number-valued measure on F*(K), and some related notions, such as null-additivity, pseudo-null-additivity, null-subtraction, pseudo-null-subtraction, autocontionuous from above, autocontionuous from below, and autocontinuity of the defined fuzzy complex number-valued measures. Properties of fuzzy complex number-valued measures are studied in detail. PMID:25093202

Kinetics and mechanism of aquation and formation reactions of carbonato complexes. XII. Deuterium solvent isotope effect on the rate of acid-catalyzed decarboxylation of the carbonatobis (ethylenediamine) cobalt(III) complex ion. A mechanistic reappraisal

International Nuclear Information System (INIS)

Harris, G.M.; Hyde, K.E.

1978-01-01

A recent study of the acid-catalyzed decarboxylation of the carbonatotetrakis(pyridine)cobalt(III) complex ion showed there to be rate acceleration in D 2 O solvent, consistent with a proton-preequilibration mechanism. This observation directly contradicts the results of a similar study made some years ago of the analogous ion, carbonatobis(ethylenediamine)cobalt(III), for which there appeared to be deceleration in D 2 O solvent. A reinvestigation of the latter reaction over a much wider acidity range has now shown the earlier work to be in error. The previously proposed generalized mechanism for aquation of chelated carbonato complex ions of the form CoN 4 CO 3 + (N 4 identical with various tetramine ligand groupings of uni-, bi-, or quadridentate type) has thus been revised to include a proton equilibration step. An unexpected complication arises in the interpretation of the data for the bis(ethylenediamine) complex ion in the acidity range 0.1 + ] + ] term, overtakes and exceeds the true first-order rate constant for CO 2 release. The interesting implications of this unusual first-order successive reaction system are fully explored in the context of the present study

Role of Reactive Mn Complexes in a Litter Decomposition Model System

Science.gov (United States)

Nico, P. S.; Keiluweit, M.; Bougoure, J.; Kleber, M.; Summering, J. A.; Maynard, J. J.; Johnson, M.; Pett-Ridge, J.

2012-12-01

discuss the chemical changes induced by reaction of Mn (III)-complexes with the Zinnia cells, the impact of such reactions on cell integrity, and potential implications for soil C cycling.

The effects of model complexity and calibration period on groundwater recharge simulations

Science.gov (United States)

Moeck, Christian; Van Freyberg, Jana; Schirmer, Mario

2017-04-01

A significant number of groundwater recharge models exist that vary in terms of complexity (i.e., structure and parametrization). Typically, model selection and conceptualization is very subjective and can be a key source of uncertainty in the recharge simulations. Another source of uncertainty is the implicit assumption that model parameters, calibrated over historical periods, are also valid for the simulation period. To the best of our knowledge there is no systematic evaluation of the effect of the model complexity and calibration strategy on the performance of recharge models. To address this gap, we utilized a long-term recharge data set (20 years) from a large weighting lysimeter. We performed a differential split sample test with four groundwater recharge models that vary in terms of complexity. They were calibrated using six calibration periods with climatically contrasting conditions in a constrained Monte Carlo approach. Despite the climatically contrasting conditions, all models performed similarly well during the calibration. However, during validation a clear effect of the model structure on model performance was evident. The more complex, physically-based models predicted recharge best, even when calibration and prediction periods had very different climatic conditions. In contrast, more simplistic soil-water balance and lumped model performed poorly under such conditions. For these models we found a strong dependency on the chosen calibration period. In particular, our analysis showed that this can have relevant implications when using recharge models as decision-making tools in a broad range of applications (e.g. water availability, climate change impact studies, water resource management, etc.).

Polyphenol-Protein Complexes and Their Consequences for the Redox Activity, Structure and Function of Honey. A Current View and New Hypothesis – a Review

Directory of Open Access Journals (Sweden)

Brudzynski Katrina

2015-06-01

Full Text Available There is increasing evidence that protein complexation by honey polyphenols is changing honey structure and function. This relatively less investigated filed of honey research is presented in a context of known mechanism of formation of the stable polyphenol-protein complexes in other foods. At a core of these interactions lies the ability of polyphenols to form non-covalent and covalent bonds with proteins leading to transient and/or irreversible complexes, respectively. Honey storage and thermal processing induces non-enzymatic oxidation of polyphenols to reactive quinones and enables them to form covalent bonds with proteins. In this short review, we present data from our laboratory on previously unrecognized types of protein-polyphenol complexes that differed in size, stoichiometry, and antioxidant capacities, and the implications they have to honey antioxidant and antibacterial activities. Our intent is to provide a current understanding of protein-polyphenol complexation in honey and also some new thoughts /hypotheses that can be useful in directing future research.

The complex portal--an encyclopaedia of macromolecular complexes.

Science.gov (United States)

Meldal, Birgit H M; Forner-Martinez, Oscar; Costanzo, Maria C; Dana, Jose; Demeter, Janos; Dumousseau, Marine; Dwight, Selina S; Gaulton, Anna; Licata, Luana; Melidoni, Anna N; Ricard-Blum, Sylvie; Roechert, Bernd; Skyzypek, Marek S; Tiwari, Manu; Velankar, Sameer; Wong, Edith D; Hermjakob, Henning; Orchard, Sandra

2015-01-01

The IntAct molecular interaction database has created a new, free, open-source, manually curated resource, the Complex Portal (www.ebi.ac.uk/intact/complex), through which protein complexes from major model organisms are being collated and made available for search, viewing and download. It has been built in close collaboration with other bioinformatics services and populated with data from ChEMBL, MatrixDB, PDBe, Reactome and UniProtKB. Each entry contains information about the participating molecules (including small molecules and nucleic acids), their stoichiometry, topology and structural assembly. Complexes are annotated with details about their function, properties and complex-specific Gene Ontology (GO) terms. Consistent nomenclature is used throughout the resource with systematic names, recommended names and a list of synonyms all provided. The use of the Evidence Code Ontology allows us to indicate for which entries direct experimental evidence is available or if the complex has been inferred based on homology or orthology. The data are searchable using standard identifiers, such as UniProt, ChEBI and GO IDs, protein, gene and complex names or synonyms. This reference resource will be maintained and grow to encompass an increasing number of organisms. Input from groups and individuals with specific areas of expertise is welcome. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Complexity Plots

KAUST Repository

Thiyagalingam, Jeyarajan

2013-06-01

In this paper, we present a novel visualization technique for assisting the observation and analysis of algorithmic complexity. In comparison with conventional line graphs, this new technique is not sensitive to the units of measurement, allowing multivariate data series of different physical qualities (e.g., time, space and energy) to be juxtaposed together conveniently and consistently. It supports multivariate visualization as well as uncertainty visualization. It enables users to focus on algorithm categorization by complexity classes, while reducing visual impact caused by constants and algorithmic components that are insignificant to complexity analysis. It provides an effective means for observing the algorithmic complexity of programs with a mixture of algorithms and black-box software through visualization. Through two case studies, we demonstrate the effectiveness of complexity plots in complexity analysis in research, education and application. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

Harmonisation of food labelling regulations in Southeast Asia: benefits, challenges and implications.

Science.gov (United States)

Kasapila, William; Shaarani, Sharifudin Md

2011-01-01

In the globalised world of the 21st century, issues of food and nutrition labelling are of pre-eminent importance. Several international bodies, including the World Health Organisation and World Trade Organisation, are encouraging countries to harmonise their food and nutrition regulations with international standards, guidelines and recommendations such as those for Codex Alimentarius. Through harmonisation, these organisations envisage fewer barriers to trade and freer movement of food products between countries, which would open doors to new markets and opportunities for the food industry. In turn, increased food trade would enhance economic development and allow consumers a greater choice of products. Inevitably, however, embracing harmonisation brings along cost implications and challenges that have to be overcome. Moreover, the harmonisation process is complex and sporadic in light of the tasks that countries have to undertake; for example, updating legislation, strengthening administrative capabilities and establishing analytical laboratories. This review discusses the legislation and regulations that govern food and nutrition labelling in Southeast Asia, and highlights the discrepancies that exist in this regard, their origin and consequences. It also gives an account of the current status of harmonising labelling of pre-packaged foodstuffs in the region and explains the subsequent benefits, challenges and implications for governments, the food industry and consumers.

Current and novel insights into the neurophysiology of migraine and its implications for therapeutics.

Science.gov (United States)

Akerman, Simon; Romero-Reyes, Marcela; Holland, Philip R

2017-04-01

Migraine headache and its associated symptoms have plagued humans for two millennia. It is manifest throughout the world, and affects more than 1/6 of the global population. It is the most common brain disorder, and is characterized by moderate to severe unilateral headache that is accompanied by vomiting, nausea, photophobia, phonophobia, and other hypersensitive symptoms of the senses. While there is still a clear lack of understanding of its neurophysiology, it is beginning to be understood, and it seems to suggest migraine is a disorder of brain sensory processing, characterized by a generalized neuronal hyperexcitability. The complex symptomatology of migraine indicates that multiple neuronal systems are involved, including brainstem and diencephalic systems, which function abnormally, resulting in premonitory symptoms, ultimately evolving to affect the dural trigeminovascular system, and the pain phase of migraine. The migraineur also seems to be particularly sensitive to fluctuations in homeostasis, such as sleep, feeding and stress, reflecting the abnormality of functioning in these brainstem and diencephalic systems. Implications for therapeutic development have grown out of our understanding of migraine neurophysiology, leading to major drug classes, such as triptans, calcitonin gene-related peptide receptor antagonists, and 5-HT 1F receptor agonists, as well as neuromodulatory approaches, with the promise of more to come. The present review will discuss the current understanding of the neurophysiology of migraine, particularly migraine headache, and novel insights into the complex neural networks responsible for associated neurological symptoms, and how interaction of these networks with migraine pain pathways has implications for the development of novel therapeutics. Copyright © 2016 Elsevier Inc. All rights reserved.

Role for a Novel Usher Protein Complex in Hair Cell Synaptic Maturation

Science.gov (United States)

Zallocchi, Marisa; Meehan, Daniel T.; Delimont, Duane; Rutledge, Joseph; Gratton, Michael Anne; Flannery, John; Cosgrove, Dominic

2012-01-01

The molecular mechanisms underlying hair cell synaptic maturation are not well understood. Cadherin-23 (CDH23), protocadherin-15 (PCDH15) and the very large G-protein coupled receptor 1 (VLGR1) have been implicated in the development of cochlear hair cell stereocilia, while clarin-1 has been suggested to also play a role in synaptogenesis. Mutations in CDH23, PCDH15, VLGR1 and clarin-1 cause Usher syndrome, characterized by congenital deafness, vestibular dysfunction and retinitis pigmentosa. Here we show developmental expression of these Usher proteins in afferent spiral ganglion neurons and hair cell synapses. We identify a novel synaptic Usher complex comprised of clarin-1 and specific isoforms of CDH23, PCDH15 and VLGR1. To establish the in vivo relevance of this complex, we performed morphological and quantitative analysis of the neuronal fibers and their synapses in the Clrn1−/− mouse, which was generated by incomplete deletion of the gene. These mice showed a delay in neuronal/synaptic maturation by both immunostaining and electron microscopy. Analysis of the ribbon synapses in Ames waltzerav3J mice also suggests a delay in hair cell synaptogenesis. Collectively, these results show that, in addition to the well documented role for Usher proteins in stereocilia development, Usher protein complexes comprised of specific protein isoforms likely function in synaptic maturation as well. PMID:22363448

Role for a novel Usher protein complex in hair cell synaptic maturation.

Directory of Open Access Journals (Sweden)

Marisa Zallocchi

Full Text Available The molecular mechanisms underlying hair cell synaptic maturation are not well understood. Cadherin-23 (CDH23, protocadherin-15 (PCDH15 and the very large G-protein coupled receptor 1 (VLGR1 have been implicated in the development of cochlear hair cell stereocilia, while clarin-1 has been suggested to also play a role in synaptogenesis. Mutations in CDH23, PCDH15, VLGR1 and clarin-1 cause Usher syndrome, characterized by congenital deafness, vestibular dysfunction and retinitis pigmentosa. Here we show developmental expression of these Usher proteins in afferent spiral ganglion neurons and hair cell synapses. We identify a novel synaptic Usher complex comprised of clarin-1 and specific isoforms of CDH23, PCDH15 and VLGR1. To establish the in vivo relevance of this complex, we performed morphological and quantitative analysis of the neuronal fibers and their synapses in the Clrn1-/- mouse, which was generated by incomplete deletion of the gene. These mice showed a delay in neuronal/synaptic maturation by both immunostaining and electron microscopy. Analysis of the ribbon synapses in Ames waltzer(av3J mice also suggests a delay in hair cell synaptogenesis. Collectively, these results show that, in addition to the well documented role for Usher proteins in stereocilia development, Usher protein complexes comprised of specific protein isoforms likely function in synaptic maturation as well.

Intra-firm knowledge transfer-a qualitative case study of knowledge transfer and its implications in a soft service firm

OpenAIRE

Zheleva, Denitsa; Viklund, Alexandra

2014-01-01

The following case study aims to explore the knowledge transfer and its implications in the context of a soft service firm. The complexity of knowledge itself and the knowledge transfer process in service firms brings new challenges. The phenomenon was investigated by the application of grounded theory. Interviews were conducted with employees at a company present in the Quick Service Restaurant segment. It resulted in several findings that were not reported by previous literature. Firstly, w...

Incorporating classic adsorption isotherms into modern surface complexation models: implications for sorption of radionuclides

International Nuclear Information System (INIS)

Kulik, D.A.

2005-01-01

Full text of publication follows: Computer-aided surface complexation models (SCM) tend to replace the classic adsorption isotherm (AI) analysis in describing mineral-water interface reactions such as radionuclide sorption onto (hydr) oxides and clays. Any site-binding SCM based on the mole balance of surface sites, in fact, reproduces the (competitive) Langmuir isotherm, optionally amended with electrostatic Coulomb's non-ideal term. In most SCM implementations, it is difficult to incorporate real-surface phenomena (site heterogeneity, lateral interactions, surface condensation) described in classic AI approaches other than Langmuir's. Thermodynamic relations between SCMs and AIs that remained obscure in the past have been recently clarified using new definitions of standard and reference states of surface species [1,2]. On this basis, a method for separating the Langmuir AI into ideal (linear) and non-ideal parts [2] was applied to multi-dentate Langmuir, Frumkin, and BET isotherms. The aim of this work was to obtain the surface activity coefficient terms that make the SCM site mole balance constraints obsolete and, in this way, extend thermodynamic SCMs to cover sorption phenomena described by the respective AIs. The multi-dentate Langmuir term accounts for the site saturation with n-dentate surface species, as illustrated on modeling bi-dentate U VI complexes on goethite or SiO 2 surfaces. The Frumkin term corrects for the lateral interactions of the mono-dentate surface species; in particular, it has the same form as the Coulombic term of the constant-capacitance EDL combined with the Langmuir term. The BET term (three parameters) accounts for more than a monolayer adsorption up to the surface condensation; it can potentially describe the surface precipitation of nickel and other cations on hydroxides and clay minerals. All three non-ideal terms (in GEM SCMs implementation [1,2]) by now are used for non-competing surface species only. Upon 'surface dilution

Naked mole-rats maintain healthy skeletal muscle and Complex IV mitochondrial enzyme function into old age.

Science.gov (United States)

Stoll, Elizabeth A; Karapavlovic, Nevena; Rosa, Hannah; Woodmass, Michael; Rygiel, Karolina; White, Kathryn; Turnbull, Douglass M; Faulkes, Chris G

2016-12-19

The naked mole-rat (NMR) Heterocephalus glaber is an exceptionally long-lived rodent, living up to 32 years in captivity. This extended lifespan is accompanied by a phenotype of negligible senescence, a phenomenon of very slow changes in the expected physiological characteristics with age. One of the many consequences of normal aging in mammals is the devastating and progressive loss of skeletal muscle, termed sarcopenia, caused in part by respiratory enzyme dysfunction within the mitochondria of skeletal muscle fibers. Here we report that NMRs avoid sarcopenia for decades. Muscle fiber integrity and mitochondrial ultrastructure are largely maintained in aged animals. While mitochondrial Complex IV expression and activity remains stable, Complex I expression is significantly decreased. We show that aged naked mole-rat skeletal muscle tissue contains some mitochondrial DNA rearrangements, although the common mitochondrial DNA deletions associated with aging in human and other rodent skeletal muscles are not present. Interestingly, NMR skeletal muscle fibers demonstrate a significant increase in mitochondrial DNA copy number. These results have intriguing implications for the role of mitochondria in aging, suggesting Complex IV, but not Complex I, function is maintained in the long-lived naked mole rat, where sarcopenia is avoided and healthy muscle function is maintained for decades.

Complex differential geometry

CERN Document Server

Zheng, Fangyang

2002-01-01

The theory of complex manifolds overlaps with several branches of mathematics, including differential geometry, algebraic geometry, several complex variables, global analysis, topology, algebraic number theory, and mathematical physics. Complex manifolds provide a rich class of geometric objects, for example the (common) zero locus of any generic set of complex polynomials is always a complex manifold. Yet complex manifolds behave differently than generic smooth manifolds; they are more coherent and fragile. The rich yet restrictive character of complex manifolds makes them a special and interesting object of study. This book is a self-contained graduate textbook that discusses the differential geometric aspects of complex manifolds. The first part contains standard materials from general topology, differentiable manifolds, and basic Riemannian geometry. The second part discusses complex manifolds and analytic varieties, sheaves and holomorphic vector bundles, and gives a brief account of the surface classifi...

Scaling up complex interventions: insights from a realist synthesis.

Science.gov (United States)

Willis, Cameron D; Riley, Barbara L; Stockton, Lisa; Abramowicz, Aneta; Zummach, Dana; Wong, Geoff; Robinson, Kerry L; Best, Allan

2016-12-19

Preventing chronic diseases, such as cancer, cardiovascular disease and diabetes, requires complex interventions, involving multi-component and multi-level efforts that are tailored to the contexts in which they are delivered. Despite an increasing number of complex interventions in public health, many fail to be 'scaled up'. This study aimed to increase understanding of how and under what conditions complex public health interventions may be scaled up to benefit more people and populations.A realist synthesis was conducted and discussed at an in-person workshop involving practitioners responsible for scaling up activities. Realist approaches view causality through the linkages between changes in contexts (C) that activate mechanisms (M), leading to specific outcomes (O) (CMO configurations). To focus this review, three cases of complex interventions that had been successfully scaled up were included: Vibrant Communities, Youth Build USA and Pathways to Education. A search strategy of published and grey literature related to each case was developed, involving searches of relevant databases and nominations from experts. Data extracted from included documents were classified according to CMO configurations within strategic themes. Findings were compared and contrasted with guidance from diffusion theory, and interpreted with knowledge users to identify practical implications and potential directions for future research.Four core mechanisms were identified, namely awareness, commitment, confidence and trust. These mechanisms were activated within two broad scaling up strategies, those of renewing and regenerating, and documenting success. Within each strategy, specific actions to change contexts included building partnerships, conducting evaluations, engaging political support and adapting funding models. These modified contexts triggered the identified mechanisms, leading to a range of scaling up outcomes, such as commitment of new communities, changes in relevant

(II) complexes

African Journals Online (AJOL)

activities of Schiff base tin (II) complexes. Neelofar1 ... Conclusion: All synthesized Schiff bases and their Tin (II) complexes showed high antimicrobial and ...... Singh HL. Synthesis and characterization of tin (II) complexes of fluorinated Schiff bases derived from amino acids. Spectrochim Acta Part A: Molec Biomolec.

Quasi-analytical treatment of spatially averaged radiation transfer in complex terrain

Science.gov (United States)

LöWe, H.; Helbig, N.

2012-10-01

We provide a new quasi-analytical method to compute the subgrid topographic influences on the shortwave radiation fluxes and the effective albedo in complex terrain as required for large-scale meteorological, land surface, or climate models. We investigate radiative transfer in complex terrain via the radiosity equation on isotropic Gaussian random fields. Under controlled approximations we derive expressions for domain-averaged fluxes of direct, diffuse, and terrain radiation and the sky view factor. Domain-averaged quantities can be related to a type of level-crossing probability of the random field, which is approximated by long-standing results developed for acoustic scattering at ocean boundaries. This allows us to express all nonlocal horizon effects in terms of a local terrain parameter, namely, the mean-square slope. Emerging integrals are computed numerically, and fit formulas are given for practical purposes. As an implication of our approach, we provide an expression for the effective albedo of complex terrain in terms of the Sun elevation angle, mean-square slope, the area-averaged surface albedo, and the ratio of atmospheric direct beam to diffuse radiation. For demonstration we compute the decrease of the effective albedo relative to the area-averaged albedo in Switzerland for idealized snow-covered and clear-sky conditions at noon in winter. We find an average decrease of 5.8% and spatial patterns which originate from characteristics of the underlying relief. Limitations and possible generalizations of the method are discussed.

The mediator complex in genomic and non-genomic signaling in cancer.

Science.gov (United States)

Weber, Hannah; Garabedian, Michael J

2018-05-01

Mediator is a conserved, multi-subunit macromolecular machine divided structurally into head, middle, and tail modules, along with a transiently associating kinase module. Mediator functions as an integrator of transcriptional regulatory activity by interacting with DNA-bound transcription factors and with RNA polymerase II (Pol II) to both activate and repress gene expression. Mediator has been shown to affect multiple steps in transcription, including chromatin looping between enhancers and promoters, pre-initiation complex formation, transcriptional elongation, and mRNA splicing. Individual Mediator subunits participate in regulation of gene expression by the estrogen and androgen receptors and are altered in a number of endocrine cancers, including breast and prostate cancer. In addition to its role in genomic signaling, MED12 has been implicated in non-genomic signaling by interacting with and activating TGF-beta receptor 2 in the cytoplasm. Recent structural studies have revealed extensive inter-domain interactions and complex architecture of the Mediator-Pol II complex, suggesting that Mediator is capable of reorganizing its conformation and composition to fit cellular needs. We propose that alterations in Mediator subunit expression that occur in various cancers could impact the organization and function of Mediator, resulting in changes in gene expression that promote malignancy. A better understanding of the role of Mediator in cancer could reveal new approaches to the diagnosis and treatment of Mediator-dependent endocrine cancers, especially in settings of therapy resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

Molecular-level spectroscopic investigations of the complexation and photodegradation of catechol to/by iron(III)

Science.gov (United States)

Al-Abadleh, Hind; Tofan-Lazar, Julia; Situm, Arthur; Slikboer, Samantha

2014-05-01

Surface water plays a crucial role in facilitating or inhibiting surface reactions in atmospheric aerosols. Little is known about the role of surface water in the complexation of organic molecules to transition metals in multicomponent aerosol systems. We will show results from real time diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments for the in situ complexation of catechol to Fe(III) and its photosensitized degradation under dry and humid conditions. Catechol was chosen as a simple model for humic-like substances (HULIS) in aerosols and aged polyaromatic hydrocarbons (PAH). It has also been detected in secondary organic aerosols (SOA) formed from the reaction of hydroxyl radicals with benzene. Given the importance of the iron content in aerosols and its biogeochemistry, our studies were conducted using FeCl3. For comparison, these surface-sensitive studies were complemented with bulk aqueous ATR-FTIR, UV-vis, and HPLC measurements for structural, quantitative and qualitative information about complexes in the bulk, and potential degradation products. The implications of our studies on understanding interfacial and condensed phase chemistry relevant to multicomponent aerosols, water thin islands on buildings, and ocean surfaces containing transition metals will be discussed.

The Complexities of Interstellar Dust and the Implications for the Small-scale Structure in the Cosmic Microwave Background

Science.gov (United States)

Verschuur, G. L.; Schmelz, J. T.

2018-02-01

A detailed comparison of the full range of PLANCK and Wilkinson Microwave Anisotropy Probe data for small (2° × 2°) areas of sky and the Cosmic Microwave Background Internal Linear Combination (ILC) maps reveals that the structure of foreground dust may be more complex than previously thought. If 857 and 353 GHz emission is dominated by galactic dust at a distance data also show that there is no single answer for the question: “to what extent does dust contaminate the cosmologically important 143 GHz data?” In some directions, the contamination appears to be quite strong, but in others, it is less of an issue. This complexity needs to be taken in account in order to derive an accurate foreground mask in the quest to understand the Cosmic Microwave Background small-scale structure. We hope that a continued investigation of these data will lead to a definitive answer to the question above and, possibly, to new scientific insights on interstellar matter, the Cosmic Microwave Background, or both.

The economic implications of the enteric disease complex and its control by the utilization of pleuromutillins in swine

Directory of Open Access Journals (Sweden)

Veturia Ileana Nueleanu

2007-12-01

Full Text Available The enteric disease complex may have a great economic impact by decreasing the growth of the animals, the conversion-rate of the fodder and, implicitly, the quality of carcass. That results in low production values, in correlation with low costs of production and decreased profitability. A therapeutic protocol was established, being administered tiamullin in the period of maximum incidence ofthe disease –5 days before and after weaning in pig youth, and the same period of time for the fatten pigs. The average meat production increased with 37.04% in youth pigs and 29.23% in fat pigs, in comparison with the period before the therapy. The profit that was achieved in youth pigs was 95 %, in comparison with the investment (the medication that was 5 %. The value of the investment was 27% in fat pigs, in comparison with the materialized profit of 73 %. The ratio between the total investment values (tiamullin medication and the benefit obtained in posttherapeutic period was 1:3.76, for the enteric disease complex in swine.

Gold(III) biosorption and bioreduction with the brown alga Fucus vesiculosus.

Science.gov (United States)

Mata, Y N; Torres, E; Blázquez, M L; Ballester, A; González, F; Muñoz, J A

2009-07-30

In this paper, the bioreduction of Au(III) to Au(0) using biomass of the brown alga Fucus vesiculosus was investigated. The recovery and reduction process took place in two stages with an optimum pH range of 4-9 with a maximum uptake obtained at pH 7. In the first stage, an induction period previous to gold reduction, the variation of pH, redox potential and gold concentration in solution was practically negligible and no color change was observed. In the second stage, the gold reduction was followed by a sharp decrease of gold concentration, pH and redox potential of solution and a color change from yellow to reddish purple. Hydroxyl groups present in the algal polysaccharides were involved in the gold bioreduction. Metallic gold was detected as microprecipitates on the biomass surface and in colloidal form as nanoparticles in the solution. Bioreduction with F. vesiculosus could be an alternative and environmentally friendly process that can be used for recovering gold from dilute hydrometallurgical solutions and leachates of electronic scraps, and for the synthesis of gold nanoparticles of different size and shape.

Gold(III) biosorption and bioreduction with the brown alga Fucus vesiculosus

International Nuclear Information System (INIS)

Mata, Y.N.; Torres, E.; Blazquez, M.L.; Ballester, A.; Gonzalez, F.; Munoz, J.A.

2009-01-01

In this paper, the bioreduction of Au(III) to Au(0) using biomass of the brown alga Fucus vesiculosus was investigated. The recovery and reduction process took place in two stages with an optimum pH range of 4-9 with a maximum uptake obtained at pH 7. In the first stage, an induction period previous to gold reduction, the variation of pH, redox potential and gold concentration in solution was practically negligible and no color change was observed. In the second stage, the gold reduction was followed by a sharp decrease of gold concentration, pH and redox potential of solution and a color change from yellow to reddish purple. Hydroxyl groups present in the algal polysaccharides were involved in the gold bioreduction. Metallic gold was detected as microprecipitates on the biomass surface and in colloidal form as nanoparticles in the solution. Bioreduction with F. vesiculosus could be an alternative and environmentally friendly process that can be used for recovering gold from dilute hydrometallurgical solutions and leachates of electronic scraps, and for the synthesis of gold nanoparticles of different size and shape.

Beyond Contagion: Reality Mining Reveals Complex Patterns of Social Influence.

Directory of Open Access Journals (Sweden)

Aamena Alshamsi

Full Text Available Contagion, a concept from epidemiology, has long been used to characterize social influence on people's behavior and affective (emotional states. While it has revealed many useful insights, it is not clear whether the contagion metaphor is sufficient to fully characterize the complex dynamics of psychological states in a social context. Using wearable sensors that capture daily face-to-face interaction, combined with three daily experience sampling surveys, we collected the most comprehensive data set of personality and emotion dynamics of an entire community of work. From this high-resolution data about actual (rather than self-reported face-to-face interaction, a complex picture emerges where contagion (that can be seen as adaptation of behavioral responses to the behavior of other people cannot fully capture the dynamics of transitory states. We found that social influence has two opposing effects on states: adaptation effects that go beyond mere contagion, and complementarity effects whereby individuals' behaviors tend to complement the behaviors of others. Surprisingly, these effects can exhibit completely different directions depending on the stable personality or emotional dispositions (stable traits of target individuals. Our findings provide a foundation for richer models of social dynamics, and have implications on organizational engineering and workplace well-being.

Beyond Contagion: Reality Mining Reveals Complex Patterns of Social Influence.

Science.gov (United States)

Alshamsi, Aamena; Pianesi, Fabio; Lepri, Bruno; Pentland, Alex; Rahwan, Iyad

2015-01-01

Contagion, a concept from epidemiology, has long been used to characterize social influence on people's behavior and affective (emotional) states. While it has revealed many useful insights, it is not clear whether the contagion metaphor is sufficient to fully characterize the complex dynamics of psychological states in a social context. Using wearable sensors that capture daily face-to-face interaction, combined with three daily experience sampling surveys, we collected the most comprehensive data set of personality and emotion dynamics of an entire community of work. From this high-resolution data about actual (rather than self-reported) face-to-face interaction, a complex picture emerges where contagion (that can be seen as adaptation of behavioral responses to the behavior of other people) cannot fully capture the dynamics of transitory states. We found that social influence has two opposing effects on states: adaptation effects that go beyond mere contagion, and complementarity effects whereby individuals' behaviors tend to complement the behaviors of others. Surprisingly, these effects can exhibit completely different directions depending on the stable personality or emotional dispositions (stable traits) of target individuals. Our findings provide a foundation for richer models of social dynamics, and have implications on organizational engineering and workplace well-being.

The molecular basis of FHA domain:phosphopeptide binding specificity and implications for phospho-dependent signaling mechanisms.

Science.gov (United States)

Durocher, D; Taylor, I A; Sarbassova, D; Haire, L F; Westcott, S L; Jackson, S P; Smerdon, S J; Yaffe, M B

2000-11-01

Forkhead-associated (FHA) domains are a class of ubiquitous signaling modules that appear to function through interactions with phosphorylated target molecules. We have used oriented peptide library screening to determine the optimal phosphopeptide binding motifs recognized by several FHA domains, including those within a number of DNA damage checkpoint kinases, and determined the X-ray structure of Rad53p-FHA1, in complex with a phospho-threonine peptide, at 1.6 A resolution. The structure reveals a striking similarity to the MH2 domains of Smad tumor suppressor proteins and reveals a mode of peptide binding that differs from SH2, 14-3-3, or PTB domain complexes. These results have important implications for DNA damage signaling and CHK2-dependent tumor suppression, and they indicate that FHA domains play important and unsuspected roles in S/T kinase signaling mechanisms in prokaryotes and eukaryotes.

Noise-induced polarization switching in complex networks

Science.gov (United States)

Haerter, Jan O.; Díaz-Guilera, Albert; Serrano, M. Ángeles

2017-04-01

The combination of bistability and noise is ubiquitous in complex systems, from biology to social interactions, and has important implications for their functioning and resilience. Here we use a simple three-state dynamical process, in which nodes go from one pole to another through an intermediate state, to show that noise can induce polarization switching in bistable systems if dynamical correlations are significant. In large, fully connected networks, where dynamical correlations can be neglected, increasing noise yields a collapse of bistability to an unpolarized configuration where the three possible states of the nodes are equally likely. In contrast, increased noise induces abrupt and irreversible polarization switching in sparsely connected networks. In multiplexes, where each layer can have a different polarization tendency, one layer is dominant and progressively imposes its polarization state on the other, offsetting or promoting the ability of noise to switch its polarization. Overall, we show that the interplay of noise and dynamical correlations can yield discontinuous transitions between extremes, which cannot be explained by a simple mean-field description.

On the complex non-linear interaction between bacteria and redox dynamics in sediments and its effects on water quality

Science.gov (United States)

Sanchez-Vila, X.; Rubol, S.; Fernandez-Garcia, D.

2011-12-01

Despite the fact that the prognoses on the availability of resources related to different climate scenarios have been already formulated, the complex hydrological and biogeochemical reactions taking place in different compartments in natural environmental media are poorly understood, especially regarding the interactions between water bodies, and the reactions taking place at soil-water interfaces. Amongst them, the inter-relationship between hydrology, chemistry and biology has important implications in natural (rivers, lakes) and man-made water facilities (lagoons, artificial recharge pounds, reservoirs, slow infiltration systems, etc). The consequences involve environment, economic, social and health-risk aspects. At the current stage, only limited explanations are available to understand the implications of these relationships on ecosystem services, water quality and water quantity. Therefore, there is an urgent need to seek a full understanding of these physical-biogeochemical processes in water-bodies, sediments and biota and its implications in ecological and health risk. We present a soil column experiment and a mathematical model which aim to study the mutual interplay between water and bacteria activity in porous media, the corresponding dynamics and the feedback on nutrient cycling by using a multidisciplinary approach.

Workshop on Recommendation in Complex Scenarios (ComplexRec 2017)

DEFF Research Database (Denmark)

Bogers, Toine; Koolen, Marijn; Mobasher, Bamshad

2017-01-01

Recommendation algorithms for ratings prediction and item ranking have steadily matured during the past decade. However, these state-of-the-art algorithms are typically applied in relatively straightforward scenarios. In reality, recommendation is often a more complex problem: it is usually just...... a single step in the user's more complex background need. These background needs can often place a variety of constraints on which recommendations are interesting to the user and when they are appropriate. However, relatively little research has been done on these complex recommendation scenarios....... The ComplexRec 2017 workshop addressed this by providing an interactive venue for discussing approaches to recommendation in complex scenarios that have no simple one-size-fits-all-solution....

Multiple telecouplings and their complex interrelationships

Directory of Open Access Journals (Sweden)

Jianguo Liu

2015-09-01

Full Text Available Increasingly, the world is becoming socioeconomically and environmentally connected, but many studies have focused on human-environment interactions within a particular area. Although some studies have considered the impacts of external factors, there is little research on multiple reciprocal socioeconomic and environmental interactions between a focal area and other areas. Here we address this important knowledge gap by applying the new integrated framework of telecouplings (socioeconomic and environmental interactions between two or more areas over distances. Results show that even a protected area - i.e., the Wolong Nature Reserve for giant pandas in southwest China - has multiple telecoupling processes with the rest of the world; these include panda loans, tourism, information dissemination, conservation subsidies, and trade of agricultural and industrial products. The telecoupling processes exhibit nonlinear patterns, they change over time, and they have varying socioeconomic and environmental effects across the world. We also find complex relationships among different telecouplings - e.g., amplification, offsetting, spatial overlaps - which cannot be detected by traditional separate studies. Such an integrated study leads to a more comprehensive understanding of distant human-environment interactions and has significant implications for global sustainability and human well-being.

Drug-drug interactions of antifungal agents and implications for patient care.

Science.gov (United States)

Gubbins, Paul O; Amsden, Jarrett R

2005-10-01

Drug interactions in the gastrointestinal tract, liver and kidneys result from alterations in pH, ionic complexation, and interference with membrane transport proteins and enzymatic processes involved in intestinal absorption, enteric and hepatic metabolism, renal filtration and excretion. Azole antifungals can be involved in drug interactions at all the sites, by one or more of the above mechanisms. Consequently, azoles interact with a vast array of compounds. Drug-drug interactions associated with amphotericin B formulations are predictable and result from the renal toxicity and electrolyte disturbances associated with these compounds. The echinocandins are unknown cytochrome P450 substrates and to date are relatively devoid of significant drug-drug interactions. This article reviews drug interactions involving antifungal agents that affect other agents and implications for patient care are highlighted.

Circadian Effects on Simple Components of Complex Task Performance

Science.gov (United States)

Clegg, Benjamin A.; Wickens, Christopher D.; Vieane, Alex Z.; Gutzwiller, Robert S.; Sebok, Angelia L.

2015-01-01

The goal of this study was to advance understanding and prediction of the impact of circadian rhythm on aspects of complex task performance during unexpected automation failures, and subsequent fault management. Participants trained on two tasks: a process control simulation, featuring automated support; and a multi-tasking platform. Participants then completed one task in a very early morning (circadian night) session, and the other during a late afternoon (circadian day) session. Small effects of time of day were seen on simple components of task performance, but impacts on more demanding components, such as those that occur following an automation failure, were muted relative to previous studies where circadian rhythm was compounded with sleep deprivation and fatigue. Circadian low participants engaged in compensatory strategies, rather than passively monitoring the automation. The findings and implications are discussed in the context of a model that includes the effects of sleep and fatigue factors.

Is Model-Based Development a Favorable Approach for Complex and Safety-Critical Computer Systems on Commercial Aircraft?

Science.gov (United States)

Torres-Pomales, Wilfredo

2014-01-01

A system is safety-critical if its failure can endanger human life or cause significant damage to property or the environment. State-of-the-art computer systems on commercial aircraft are highly complex, software-intensive, functionally integrated, and network-centric systems of systems. Ensuring that such systems are safe and comply with existing safety regulations is costly and time-consuming as the level of rigor in the development process, especially the validation and verification activities, is determined by considerations of system complexity and safety criticality. A significant degree of care and deep insight into the operational principles of these systems is required to ensure adequate coverage of all design implications relevant to system safety. Model-based development methodologies, methods, tools, and techniques facilitate collaboration and enable the use of common design artifacts among groups dealing with different aspects of the development of a system. This paper examines the application of model-based development to complex and safety-critical aircraft computer systems. Benefits and detriments are identified and an overall assessment of the approach is given.

Occurrence and mineral chemistry of chromite and related silicates from the Hongshishan mafic-ultramafic complex, NW China with petrogenetic implications

Science.gov (United States)

Ruan, Banxiao; Yu, Yingmin; Lv, Xinbiao; Feng, Jing; Wei, Wei; Wu, Chunming; Wang, Heng

2017-10-01

The Hongshishan mafic-ultramafic complex is located in the western Beishan Terrane, NW China, and hosts an economic Ni-Cu deposit. Chromite as accessory mineral from the complex is divided into three types based on its occurrence and morphology. Quantitative electron probe microanalysis (EPMA) have been conducted on the different types of chromites. Type 1 chromite occurs as inclusions within silicate minerals and has relatively homogeneous composition. Type 2 chromite occurs among serpentine, as interstitial phase. Type 3 chromite is zoned and exhibits a sudden change in compositions from core to rim. Type 1 chromite occurs in olivine gabbro and troctolite showing homogeneous composition. This chromite is more likely primary. Interstitial type 2 and zoned type 3 chromite has compositional variation from core to rim and is more likely modified. Abundant inclusions of orthopyroxene, phlogopite and hornblende occur within type 2 and type 3 chromites. The parental melt of type 1 chromite has an estimated composition of 14.5 wt% MgO, 12.3 wt% Al2O3 and 1.9 wt% TiO2 and is characterized by high temperature, picritic affinity, hydrous nature and high Mg and Ti contents. Compositions of chromite and clinopyroxene are distinct from those of Alaskan-type complexes and imply that the subduction-related environment is not reasonable. Post orogenic extension and the early Permian mantle plume are responsible for the emplacement of mafic-ultramafic complexes in the Beishan Terrane. The cores of zoned chromites are classified as ferrous chromite and the rims as ferrian chromite. The formation of ferrian rim involves reaction of ferrous chromite, forsterite and magnetite to produce ferrian chromite and chlorite, or alternaively, the rim can be simply envisioned as the result of external addition of magnetite in solution to the already formed ferrous chromite.

Encapsulation of ferro- and ferricyanide complexes inside ZSM-5 zeolite synthesized from rice straw: Implications for synthesis of Prussian blue pigment

International Nuclear Information System (INIS)

Ali, Ibraheem O.; Salama, Tarek M.; Thabet, Mohamed S.; El-Nasser, Karam S.; Hassan, Ali M.

2013-01-01

Encapsulation of [Fe(CN) 6 ] 4− and [Fe(CN) 6 ] 3− complexes in the intracrystalline pores of ZSM-5 zeolite, Fe II L/Z and Fe III L/Z respectively, by the zeolite synthesis method was reported. The modified zeolites were characterized by powder XRD, FT-IR and UV–vis spectroscopy. The nitrogen adsorption isotherms allow for the evaluation of pore structure of the complex-modified zeolites, whereas the thermal analysis (TGA/DTA) measurements provide insight into the decomposition products of the immobilized complexes. The modified zeolites exhibited smaller pore volumes and surface areas as compared with those of unpromoted ZSM-5, suggesting the inclusion of iron cyanides inside the interconnecting channels of ZSM-5. While the ferricyanide complex enhanced the formation of highly crystalline zeolite, the ferrocyanide one resulted in a lesser effect. The electronic spectra of the colloidal species developed when Fe III L/Z brought in contact with an aqueous solution of [Fe(CN) 6 ] 3− exhibit absorptions attributed to CN − → iron charge-transfer. New bands at 294 and 319 nm due to d–d transitions of Fe III tetrahedral monomeric moieties were emitted concurrently under successive adsorption of [Fe(CN) 6 ] aq 3− over Fe III L/Z, along with a broad band at 555 nm assigned to polymeric [Fe II –C–N–Fe III ] of Prussian blue (PB). The FT-IR spectra of Fe III/II L/Z devoted to the adsorption of an aqueous solution of [Fe(CN) 6 ] 3− showed a band at 2092 cm −1 assigned to the C–N stretch in the Fe II –CN–Fe III linkages. The vibrations attributable to Fe–O–Si bonding along with hydrocarbon and nitroprusside appeared only in the spectrum of Fe III L/Z, thus was found to be strong evidence for the mutual interaction between [Fe(CN) 6 ] 3− and the latter sample. - Highlights: • We synthesized ferrous and ferric cyanide complexes inside ZSM-5 zeolite. • The decomposition of the encapsulated complexes occurred at high temperatures. �

Selective liquid-liquid extraction of antimony(III from hydrochloric acid media by N-n-octylaniline in xylene

Directory of Open Access Journals (Sweden)

M. A. ANUSE

2004-04-01

Full Text Available N-n-Octylaniline in xylene was used for the extraction separation of antimony(III from hydrochloric acid media. Antimony(III was extracted quantitatively with 10 mL 4 % N-n-octylaniline in xylene. It was stripped from the organic phase with 0.5 M ammonia and estimated photometrically by the iodide method. The effect of metal ion, acid, reagent concentration and various foreign ions was investigated. The method affords binary and ternary separation of antimony(III from tellurium(IV, selenium(IV, lead(II, bismuth(III, tin(IV, germanium(IV, copper(II, gold(III, iron(III and zinc(II. The method is applicable for the analysis of synthetic mixtures, alloys and semiconductor thin films. It is fast, accurate and precise.

Anticipating the Future, Influencing the Present: Assessing the Societal Implications of Emerging Technologies

Science.gov (United States)

Michelson, Evan S.

A growing challenge for the American policymaking system is to respond effectively to a wide range of interconnected, complex, long-term science and technology issues. Simultaneously, current approaches and institutions of governance are ill suited to address these multidimensional challenges. As the next generation of innovations in science and technology is arriving at an accelerating rate, the governance system is lagging behind. This realization leads to a vital overarching consideration that steers this study: What approaches are well suited to anticipate the longer-term societal implications of emerging technologies in the 21st Century? This study identifies and examines strategies for anticipating the longer-term societal implications of emerging technologies by way of a qualitative case study. It explores one area of technology (nanotechnology), in one particular governance system (the United States), and with a focus on one high profile non-governmental organization (NGO) involved in addressing a range of nanotechnology's societal and policy implications: the Project on Emerging Nanotechnologies (PEN). Based at the Woodrow Wilson International Center for Scholars, PEN's goal was to ensure "that as nanotechnologies advance, possible risks are minimized, public and consumer engagement remains strong, and the potential benefits of these new technologies are realized." The conceptual framework of anticipatory governance guides the research, which offers a real-world example about how anticipatory governance applies in the nongovernmental sector and shows how this idea links to broader theoretical debates about the policymaking process. The study's main conclusion is that PEN utilized a set of interconnected strategies related to advancing foresight, operating in a boundary-spanning role, and promoting communications and public engagement in its attempt to influence, anticipate, and shape the societal implications of emerging technologies. The findings are

An Adenovirus DNA Replication Factor, but Not Incoming Genome Complexes, Targets PML Nuclear Bodies.

Science.gov (United States)

Komatsu, Tetsuro; Nagata, Kyosuke; Wodrich, Harald

2016-02-01

Promyelocytic leukemia protein nuclear bodies (PML-NBs) are subnuclear domains implicated in cellular antiviral responses. Despite the antiviral activity, several nuclear replicating DNA viruses use the domains as deposition sites for the incoming viral genomes and/or as sites for viral DNA replication, suggesting that PML-NBs are functionally relevant during early viral infection to establish productive replication. Although PML-NBs and their components have also been implicated in the adenoviral life cycle, it remains unclear whether incoming adenoviral genome complexes target PML-NBs. Here we show using immunofluorescence and live-cell imaging analyses that incoming adenovirus genome complexes neither localize at nor recruit components of PML-NBs during early phases of infection. We further show that the viral DNA binding protein (DBP), an early expressed viral gene and essential DNA replication factor, independently targets PML-NBs. We show that DBP oligomerization is required to selectively recruit the PML-NB components Sp100 and USP7. Depletion experiments suggest that the absence of one PML-NB component might not affect the recruitment of other components toward DBP oligomers. Thus, our findings suggest a model in which an adenoviral DNA replication factor, but not incoming viral genome complexes, targets and modulates PML-NBs to support a conducive state for viral DNA replication and argue against a generalized concept that PML-NBs target incoming viral genomes. The immediate fate upon nuclear delivery of genomes of incoming DNA viruses is largely unclear. Early reports suggested that incoming genomes of herpesviruses are targeted and repressed by PML-NBs immediately upon nuclear import. Genome localization and/or viral DNA replication has also been observed at PML-NBs for other DNA viruses. Thus, it was suggested that PML-NBs may immediately sense and target nuclear viral genomes and hence serve as sites for deposition of incoming viral genomes and

Maritime Violence : Implications to Malaysia

OpenAIRE

Zubir, Nurulizwan Ahmad

2012-01-01

Abstract Maritime Piracy has been a serious threat to the international community especially in the SoutheastAsia region. This threat has caused tremendous implications towards the world economy, environment,political stability of the nations involved because 45% of the shipping company passes through theSoutheast Asia. The worrying fact is that these attacks were committed by terrorists as well as traditionalmaritime pirates. This paper examines on the implications of maritime crime in M...

Modeling Equilibrium Fe Isotope Fractionation in Fe-Organic Complexes: Implications for the use of Fe Isotopes as a Biomarker and Trends Based on the Properties of Bound Ligands

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Domagal-Goldman, S.; Kubicki, J. D.

2006-05-01

Fe Isotopes have been proposed as a useful tracer of biological and geochemical processes. Key to understanding the effects these various processes have on Fe isotopes is accurate modeling of the reactions responsible for the isotope fractionations. In this study, we examined the theoretical basis for the claims that Fe isotopes can be used as a biomarker. This was done by using molecular orbital/density functional theory (MO/DFT) calculations to predict the equilibrium fractionation of Fe isotopes due to changes in the redox state and the bonding environment of Fe. Specifically, we predicted vibrational frequencies for iron desferrioxamine (Fe-DFOB), iron triscatechol (Fe(cat)3), iron trisoxalate (Fe(ox)3), and hexaaquo iron (Fe(H2O)6) for complexes containing both ferrous (Fe2+) and ferric (Fe3+) iron. Using these vibrational frequencies, we then predicted fractionation factors between these six complexes. The predicted fractionation factors resulting from changes in the redox state of Fe fell in the range 2.5- 3.5‰. The fractionation factors resulting from changes in the bonding environment of Fe ranged from 0.2 to 1.4‰. These results indicate that changes in the bonding strength of Fe ligands are less important to Fe isotope fractionation processes than are changes to the redox state of Fe. The implications for use of Fe as a tracer of biological processes is clear: abiological redox changes must be ruled out in a sample before Fe isotopes are considered as a potential biomarker. Furthermore, the use of Fe isotopes to measure the redox state of the Earths surface environment through time is supported by this work, since changes in the redox state of Fe appear to be the more important driver of isotopic fractionations. In addition to the large differences between redox-driven fractionations and ligand-driven fractionations, we will also show general trends in the demand for heavy Fe isotopes as a function of properties of the bound ligand. This will help the

Characterization of measurement errors using structure-from-motion and photogrammetry to measure marine habitat structural complexity.

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Bryson, Mitch; Ferrari, Renata; Figueira, Will; Pizarro, Oscar; Madin, Josh; Williams, Stefan; Byrne, Maria

2017-08-01

Habitat structural complexity is one of the most important factors in determining the makeup of biological communities. Recent advances in structure-from-motion and photogrammetry have resulted in a proliferation of 3D digital representations of habitats from which structural complexity can be measured. Little attention has been paid to quantifying the measurement errors associated with these techniques, including the variability of results under different surveying and environmental conditions. Such errors have the potential to confound studies that compare habitat complexity over space and time. This study evaluated the accuracy, precision, and bias in measurements of marine habitat structural complexity derived from structure-from-motion and photogrammetric measurements using repeated surveys of artificial reefs (with known structure) as well as natural coral reefs. We quantified measurement errors as a function of survey image coverage, actual surface rugosity, and the morphological community composition of the habitat-forming organisms (reef corals). Our results indicated that measurements could be biased by up to 7.5% of the total observed ranges of structural complexity based on the environmental conditions present during any particular survey. Positive relationships were found between measurement errors and actual complexity, and the strength of these relationships was increased when coral morphology and abundance were also used as predictors. The numerous advantages of structure-from-motion and photogrammetry techniques for quantifying and investigating marine habitats will mean that they are likely to replace traditional measurement techniques (e.g., chain-and-tape). To this end, our results have important implications for data collection and the interpretation of measurements when examining changes in habitat complexity using structure-from-motion and photogrammetry.

Dynamic complexity: plant receptor complexes at the plasma membrane.

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Burkart, Rebecca C; Stahl, Yvonne

2017-12-01

Plant receptor complexes at the cell surface perceive many different external and internal signalling molecules and relay these signals into the cell to regulate development, growth and immunity. Recent progress in the analyses of receptor complexes using different live cell imaging approaches have shown that receptor complex formation and composition are dynamic and take place at specific microdomains at the plasma membrane. In this review we focus on three prominent examples of Arabidopsis thaliana receptor complexes and how their dynamic spatio-temporal distribution at the PM has been studied recently. We will elaborate on the newly emerging concept of plasma membrane microdomains as potential hubs for specific receptor complex assembly and signalling outputs. Copyright © 2017 Elsevier Ltd. All rights reserved.

A relativistic density functional study of uranyl hydrolysis and complexation by carboxylic acids in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Ray, Rupashree Shyama

2009-02-10

In this work, the complexation of uranium in its most stable oxidation state VI in aqueous solution was studied computationally, within the framework of density functional (DF) theory. The thesis is divided into the following parts: Chapter 2 briefly summarizes the relevant general aspects of actinide chemistry and then focuses on actinide environmental chemistry. Experimental results on hydrolysis, actinide complexation by carboxylic acids, and humic substances are presented to establish a background for the subsequent discussion. Chapter 3 describes the computational method used in this work and the relevant features of the parallel quantum chemistry code PARAGAUSS employed. First, the most relevant basics of the applied density functional approach are presented focusing on relativistic effects. Then, the treatment of solvent effects, essential for an adequate modeling of actinide species in aqueous solution, will be introduced. At the end of this chapter, computational parameters and procedures will be summarized. Chapter 4 presents the computational results including a comparison to available experimental data. In the beginning, the mononuclear hydrolysis product of UO{sub 2}{sup 2+}, [UO{sub 2}OH]{sup +}, will be discussed. The second part deals with actinide complexation by carboxylate ligands. First of all the coordination number for uranylacetate will be discussed with respect to implications for the complexation of actinides by humic substances followed by the uranyl complexation of aromatic carboxylic acids in comparison to earlier results for aliphatic ones. In the end, the ternary uranyl-hydroxo-acetate are discussed, as models of uranyl humate complexation at ambient condition.

Obesity-specific neural cost of maintaining gait performance under complex conditions in community-dwelling older adults.

Science.gov (United States)

Osofundiya, Olufunmilola; Benden, Mark E; Dowdy, Diane; Mehta, Ranjana K

2016-06-01

Recent evidence of obesity-related changes in the prefrontal cortex during cognitive and seated motor activities has surfaced; however, the impact of obesity on neural activity during ambulation remains unclear. The purpose of this study was to determine obesity-specific neural cost of simple and complex ambulation in older adults. Twenty non-obese and obese individuals, 65years and older, performed three tasks varying in the types of complexity of ambulation (simple walking, walking+cognitive dual-task, and precision walking). Maximum oxygenated hemoglobin, a measure of neural activity, was measured bilaterally using a portable functional near infrared spectroscopy system, and gait speed and performance on the complex tasks were also obtained. Complex ambulatory tasks were associated with ~2-3.5 times greater cerebral oxygenation levels and ~30-40% slower gait speeds when compared to the simple walking task. Additionally, obesity was associated with three times greater oxygenation levels, particularly during the precision gait task, despite obese adults demonstrating similar gait speeds and performances on the complex gait tasks as non-obese adults. Compared to existing studies that focus solely on biomechanical outcomes, the present study is one of the first to examine obesity-related differences in neural activity during ambulation in older adults. In order to maintain gait performance, obesity was associated with higher neural costs, and this was augmented during ambulatory tasks requiring greater precision control. These preliminary findings have clinical implications in identifying individuals who are at greater risk of mobility limitations, particularly when performing complex ambulatory tasks. Copyright © 2016 Elsevier Ltd. All rights reserved.

A climate for speciation: rapid spatial diversification within the Sorex cinereus complex of shrews

Science.gov (United States)

Hope, Andrew G.; Speer, Kelly A.; Demboski, John R.; Talbot, Sandra L.; Cook, Joseph A.

2012-01-01

The cyclic climate regime of the late Quaternary caused dramatic environmental change at high latitudes. Although these events may have been brief in periodicity from an evolutionary standpoint, multiple episodes of allopatry and divergence have been implicated in rapid radiations of a number of organisms. Shrews of the Sorex cinereus complex have long challenged taxonomists due to similar morphology and parapatric geographic ranges. Here, multi-locus phylogenetic and demographic assessments using a coalescent framework were combined to investigate spatiotemporal evolution of 13 nominal species with a widespread distribution throughout North America and across Beringia into Siberia. For these species, we first test a hypothesis of recent differentiation in response to Pleistocene climate versus more ancient divergence that would coincide with pre-Pleistocene perturbations. We then investigate the processes driving diversification over multiple continents. Our genetic analyses highlight novel diversity within these morphologically conserved mammals and clarify relationships between geographic distribution and evolutionary history. Demography within and among species indicates both regional stability and rapid expansion. Ancestral ecological differentiation coincident with early cladogenesis within the complex enabled alternating and repeated episodes of allopatry and expansion where successive glacial and interglacial phases each promoted divergence. The Sorex cinereus complex constitutes a valuable model for future comparative assessments of evolution in response to cyclic environmental change.

Functional interplay between Mediator and TFIIB in preinitiation complex assembly in relation to promoter architecture.

Science.gov (United States)

Eychenne, Thomas; Novikova, Elizaveta; Barrault, Marie-Bénédicte; Alibert, Olivier; Boschiero, Claire; Peixeiro, Nuno; Cornu, David; Redeker, Virginie; Kuras, Laurent; Nicolas, Pierre; Werner, Michel; Soutourina, Julie

2016-09-15

Mediator is a large coregulator complex conserved from yeast to humans and involved in many human diseases, including cancers. Together with general transcription factors, it stimulates preinitiation complex (PIC) formation and activates RNA polymerase II (Pol II) transcription. In this study, we analyzed how Mediator acts in PIC assembly using in vivo, in vitro, and in silico approaches. We revealed an essential function of the Mediator middle module exerted through its Med10 subunit, implicating a key interaction between Mediator and TFIIB. We showed that this Mediator-TFIIB link has a global role on PIC assembly genome-wide. Moreover, the amplitude of Mediator's effect on PIC formation is gene-dependent and is related to the promoter architecture in terms of TATA elements, nucleosome occupancy, and dynamics. This study thus provides mechanistic insights into the coordinated function of Mediator and TFIIB in PIC assembly in different chromatin contexts. © 2016 Eychenne et al.; Published by Cold Spring Harbor Laboratory Press.

Revitalizing Complex Analysis: A Transition-to-Proof Course Centered on Complex Topics

Science.gov (United States)

Sachs, Robert

2017-01-01

A new transition course centered on complex topics would help in revitalizing complex analysis in two ways: first, provide early exposure to complex functions, sparking greater interest in the complex analysis course; second, create extra time in the complex analysis course by eliminating the "complex precalculus" part of the course. In…

Protein kinase A governs oxidative phosphorylation kinetics and oxidant emitting potential at complex I

Directory of Open Access Journals (Sweden)

Daniel Stephen Lark

2015-11-01

Full Text Available The mitochondrial electron transport system (ETS is responsible for setting and maintaining both the energy and redox charges throughout the cell. Reversible phosphorylation of mitochondrial proteins, particularly via the soluble adenylyl cyclase (sAC/cyclic AMP (cAMP/Protein kinase A (PKA axis, has recently been revealed as a potential mechanism regulating the ETS. However, the governance of cAMP/PKA signaling and its implications on ETS function are incompletely understood. In contrast to prior reports using exogenous bicarbonate, we provide evidence that endogenous CO2 produced by increased tricarboxylic acid (TCA cycle flux is insufficient to increase mitochondrial cAMP levels, and that exogenous addition of membrane permeant 8Br-cAMP does not enhance mitochondrial respiratory capacity. We also report important non-specific effects of commonly used inhibitors of sAC which preclude their use in studies of mitochondrial function. In isolated liver mitochondria, inhibition of PKA reduces complex I-, but not complex II-supported respiratory capacity. In permeabilized myofibers, inhibition of PKA lowers both the Km and Vmax for complex I-supported respiration as well as succinate-supported H2O2 emitting potential. In summary, the data provided here improve our understanding of how mitochondrial cAMP production is regulated, illustrate a need for better tools to examine the impact of sAC activity on mitochondrial biology, and suggest that cAMP/PKA signaling contributes to the governance of electron flow through complex I of the ETS.

Clinical review: Ethnic differences in bone mass--clinical implications.

Science.gov (United States)

Leslie, William D

2012-12-01

Differences in bone mineral density (BMD) as assessed with dual-energy x-ray absorptiometry are observed between geographic and ethnic groups, with important implications in clinical practice. PubMed was employed to identify relevant studies. A review of the literature was conducted, and data were summarized and integrated. The available data highlight the complex ethnic variations in BMD, which only partially account for observed variations in fracture rates. Factors contributing to ethnic differences include genetics, skeletal size, body size and composition, lifestyle, and social determinants. Despite BMD differences, the gradient of risk for fracture from BMD and other clinical risk factors appears to be similar across ethnic groups. Furthermore, BMD variation is greater within an ethnic population than between ethnic populations. New imaging technologies have identified ethnic differences in bone geometry, volumetric density, microarchitecture, and estimated bone strength that may contribute to a better understanding of ethnic differences in fracture risk. Factors associated with ethnicity affect BMD and fracture risk through direct and indirect mechanisms.

Comparing definitions of outpatient surgery: Implications for quality measurement.

Science.gov (United States)

Mull, Hillary J; Rivard, Peter E; Legler, Aaron; Pizer, Steven D; Hawn, Mary T; Itani, Kamal M F; Rosen, Amy K

2017-08-01

Adverse event (AE) rates in outpatient surgery are inconsistently reported, partly because of the lack of a standard definition of outpatient surgery. We compared the types and rates of surgical procedures defined by two national healthcare agencies: Health Care Cost Institute (HCCI) and the Healthcare Cost and Utilization Project (HCUP) and considered implications for quality measurement. We used HCCI and HCUP definitions to identify FY2012-14 VA outpatient surgeries. There were six times as many HCCI surgeries as HCUP (6,575,830 versus 1,086,640). Ninety-nine percent of HCUP-defined surgeries were also identified by HCCI. More HCUP surgeries had higher average Medicare Relative Value Units then HCCI surgeries [5.3 (SD = 4.4) versus 1.6 (SD = 2.3) RVUs]. Rates and types of procedures vary widely between definitions. Quality measurement using HCCI versus HCUP may produce significantly lower AE rates because many of the surgeries included reflect low complexity and potentially low risk of AEs. Published by Elsevier Inc.

A nanosized Ag–silica hybrid complex prepared by γ-irradiation activates the defense response in Arabidopsis

International Nuclear Information System (INIS)

Chu, Hyosub; Kim, Hwa-Jung; Su Kim, Joong; Kim, Min-Soo; Yoon, Byung-Dae; Park, Hae-Jun; Kim, Cha Young

2012-01-01

Silver nanoparticles have antimicrobial activity against many pathogenic microbes. Here, the preparation of a nanosized Ag–silica hybrid complex (NSS) prepared by γ-irradiation is described. The effects of both NSS and reduced Ag nanoparticles (Ag 0 ) on the growth of the model plant Arabidopsis thaliana were tested. The application of 1–10 ppm NSS complex improved Arabidopsis growth in soil, whereas 100 ppm NSS resulted in weakly curled leaves. In addition, supplementation of Murashige and Skoog (MS) growth medium with 1 ppm NSS promoted the root growth of Arabidopsis seedlings, but root growth was inhibited by supplementation with 10 ppm NSS. To investigate whether the NSS complex could induce plant defense responses, the expression of pathogenesis-related (PR) genes that are implicated in systemic acquired resistance (SAR) in Arabidopsis plants was examined. PR1, PR2 and PR5 were significantly up-regulated by each application of 10 ppm NSS complex or Ag 0 to the rosette leaves. Furthermore, pretreatment with the NSS complex induced more pathogen resistance to the virulent pathogen Pseudomonas syringae pv. tomato DC3000 (Pst) compared to water treatment in Arabidopsis plants. - Research highlights: ► We describe the preparation of silver nanoparticles using γ-irradiation technique. ► We examine the effects of silver nanoparticles on the growth of Arabidopsis. ► Silver nanoparticles induced the expression of SAR marker genes. ► Silver nanoparticles exhibited enhanced disease resistance to the bacterial pathogen.

The privacy implications of Bluetooth

OpenAIRE

Kostakos, Vassilis

2008-01-01

A substantial amount of research, as well as media hype, has surrounded RFID technology and its privacy implications. Currently, researchers and the media focus on the privacy threats posed by RFID, while consumer groups choose to boycott products bearing RFID tags. At the same, however, a very similar technology has quietly become part of our everyday lives: Bluetooth. In this paper we highlight the fact that Bluetooth is a widespread technology that has real privacy implications. Furthermor...

Quantum histories and their implications

International Nuclear Information System (INIS)

Kent, A.

2000-01-01

Classical mechanics and standard Copenhagen quantum mechanics respect subspace implications. For example, if a particle is confined in a particular region R of space, then in these theories we can deduce that it is confined in regions containing R. However, subspace implications are generally violated by versions of quantum theory that assign probabilities to histories, such as the consistent histories approach. I define here a new criterion, ordered consistency, which refines the criterion of consistency and has the property that inferences made by ordered consistent sets do not violate subspace relations. This raises the question: do the operators defining our observations form an ordered consistent history? If so, ordered consistency defines a version of quantum theory with greater predictive power than the consistent histories formalism. If not, and our observations are defined by a non-ordered consistent quantum history, then subspace implications are not generally valid. (orig.)

A Unified Framework for Complex Networks with Degree Trichotomy Based on Markov Chains.

Science.gov (United States)

Hui, David Shui Wing; Chen, Yi-Chao; Zhang, Gong; Wu, Weijie; Chen, Guanrong; Lui, John C S; Li, Yingtao

2017-06-16

This paper establishes a Markov chain model as a unified framework for describing the evolution processes in complex networks. The unique feature of the proposed model is its capability in addressing the formation mechanism that can reflect the "trichotomy" observed in degree distributions, based on which closed-form solutions can be derived. Important special cases of the proposed unified framework are those classical models, including Poisson, Exponential, Power-law distributed networks. Both simulation and experimental results demonstrate a good match of the proposed model with real datasets, showing its superiority over the classical models. Implications of the model to various applications including citation analysis, online social networks, and vehicular networks design, are also discussed in the paper.

Crystal structures of T. b. rhodesiense adenosine kinase complexed with inhibitor and activator: implications for catalysis and hyperactivation.

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Sabine Kuettel

2011-05-01

Full Text Available BACKGROUND: The essential purine salvage pathway of Trypanosoma brucei bears interesting catalytic enzymes for chemotherapeutic intervention of Human African Trypanosomiasis. Unlike mammalian cells, trypanosomes lack de novo purine synthesis and completely rely on salvage from their hosts. One of the key enzymes is adenosine kinase which catalyzes the phosphorylation of ingested adenosine to form adenosine monophosphate (AMP utilizing adenosine triphosphate (ATP as the preferred phosphoryl donor. METHODS AND FINDINGS: Here, we present the first structures of Trypanosoma brucei rhodesiense adenosine kinase (TbrAK: the structure of TbrAK in complex with the bisubstrate inhibitor P(1,P(5-di(adenosine-5'-pentaphosphate (AP5A at 1.55 Å, and TbrAK complexed with the recently discovered activator 4-[5-(4-phenoxyphenyl-2H-pyrazol-3-yl]morpholine (compound 1 at 2.8 Å resolution. CONCLUSIONS: The structural details and their comparison give new insights into substrate and activator binding to TbrAK at the molecular level. Further structure-activity relationship analyses of a series of derivatives of compound 1 support the observed binding mode of the activator and provide a possible mechanism of action with respect to their activating effect towards TbrAK.

Complex trauma and mental health in children and adolescents placed in foster care: findings from the National Child Traumatic Stress Network.

Science.gov (United States)

Greeson, Johanna K P; Briggs, Ernestine C; Kisiel, Cassandra L; Layne, Christopher M; Ake, George S; Ko, Susan J; Gerrity, Ellen T; Steinberg, Alan M; Howard, Michael L; Pynoos, Robert S; Fairbank, John A

2011-01-01

Many children in the child welfare system (CWS) have histories of recurrent interpersonal trauma perpetrated by caregivers early in life often referred to as complex trauma. Children in the CWS also experience a diverse range of reactions across multiple areas of functioning that are associated with such exposure. Nevertheless, few CWSs routinely screen for trauma exposure and associated symptoms beyond an initial assessment of the precipitating event. This study examines trauma histories, including complex trauma exposure (physical abuse, sexual abuse, emotional abuse, neglect, domestic violence), posttraumatic stress, and behavioral and emotional problems of 2,251 youth (age 0 to 21; M = 9.5, SD = 4.3) in foster care who were referred to a National Child Traumatic Stress Network site for treatment. High prevalence rates of complex trauma exposure were observed: 70.4% of the sample reported at least two of the traumas that constitute complex trauma; 11.7% of the sample reported all 5 types. Compared to youth with other types of trauma, those with complex trauma histories had significantly higher rates of internalizing problems, posttraumatic stress, and clinical diagnoses, and differed on some demographic variables. Implications for child welfare practice and future research are discussed.

HIC1 interacts with a specific subunit of SWI/SNF complexes, ARID1A/BAF250A

International Nuclear Information System (INIS)

Van Rechem, Capucine; Boulay, Gaylor; Leprince, Dominique

2009-01-01

HIC1, a tumor suppressor gene epigenetically silenced in many human cancers encodes a transcriptional repressor involved in regulatory loops modulating p53-dependent and E2F1-dependent cell survival and stress responses. HIC1 is also implicated in growth control since it recruits BRG1, one of the two alternative ATPases (BRM or BRG1) of SWI/SNF chromatin-remodeling complexes to repress transcription of E2F1 in quiescent fibroblasts. Here, through yeast two-hybrid screening, we identify ARID1A/BAF250A, as a new HIC1 partner. ARID1A/BAF250A is one of the two mutually exclusive ARID1-containing subunits of SWI/SNF complexes which define subsets of complexes endowed with anti-proliferative properties. Co-immunoprecipitation assays in WI38 fibroblasts and in BRG1-/- SW13 cells showed that endogenous HIC1 and ARID1A proteins interact in a BRG1-dependent manner. Furthermore, we demonstrate that HIC1 does not interact with BRM. Finally, sequential chromatin immunoprecipitation (ChIP-reChIP) experiments demonstrated that HIC1 represses E2F1 through the recruitment of anti-proliferative SWI/SNF complexes containing ARID1A.

The Evolution of General Internal Medicine (GIM)in Canada: International Implications.

Science.gov (United States)

Card, Sharon E; Clark, Heather D; Elizov, Michelle; Kassam, Narmin

2017-05-01

General internal medicine (GIM), like other generalist specialties, has struggled to maintain its identity in the face of mounting sub-specialization over the past few decades. In Canada, the path to licensure for general internists has been through the completion of an extra year of training after three core years of internal medicine. Until very recently, the Royal College of Physicians and Surgeons of Canada (RCPSC) did not recognize GIM as a distinct entity. In response to a societal need to train generalist practitioners who could care for complex patients in an increasingly complex health care setting, the majority of universities across Canada voluntarily developed structured GIM training programs independent of RCPSC recognition. However, interest amongst trainees in GIM was declining, and the GIM workforce in Canada, like that in many other countries, was in danger of serious shortfalls. After much deliberation and consultation, in 2010, the RCPSC recognized GIM as a distinct subspecialty of internal medicine. Since this time, despite the challenges in the educational implementation of GIM as a distinct discipline, there has been a resurgence of interest in this field of medicine. This paper outlines the journey of the Canadian GIM to educational implementation as a distinct discipline, the impact on the discipline, and the implications for the international GIM community.

Ophthalmic implications of seasonal affective disorder

International Nuclear Information System (INIS)

Paramore, J.E.; King, V.M.

1989-01-01

A review of seasonal affective disorder (SAD) is presented with a discussion of its standard treatment of phototherapy. A number of ophthalmic implications related to SAD are proposed. These implications relate to both the condition and the phototherapy used in its treatment, especially the use of full spectrum light which contains ultraviolet and near ultraviolet radiation. 12 references

3D complex: a structural classification of protein complexes.

Directory of Open Access Journals (Sweden)

Emmanuel D Levy

2006-11-01

Full Text Available Most of the proteins in a cell assemble into complexes to carry out their function. It is therefore crucial to understand the physicochemical properties as well as the evolution of interactions between proteins. The Protein Data Bank represents an important source of information for such studies, because more than half of the structures are homo- or heteromeric protein complexes. Here we propose the first hierarchical classification of whole protein complexes of known 3-D structure, based on representing their fundamental structural features as a graph. This classification provides the first overview of all the complexes in the Protein Data Bank and allows nonredundant sets to be derived at different levels of detail. This reveals that between one-half and two-thirds of known structures are multimeric, depending on the level of redundancy accepted. We also analyse the structures in terms of the topological arrangement of their subunits and find that they form a small number of arrangements compared with all theoretically possible ones. This is because most complexes contain four subunits or less, and the large majority are homomeric. In addition, there is a strong tendency for symmetry in complexes, even for heteromeric complexes. Finally, through comparison of Biological Units in the Protein Data Bank with the Protein Quaternary Structure database, we identified many possible errors in quaternary structure assignments. Our classification, available as a database and Web server at http://www.3Dcomplex.org, will be a starting point for future work aimed at understanding the structure and evolution of protein complexes.

Unraveling chaotic attractors by complex networks and measurements of stock market complexity

International Nuclear Information System (INIS)

Cao, Hongduo; Li, Ying

2014-01-01

We present a novel method for measuring the complexity of a time series by unraveling a chaotic attractor modeled on complex networks. The complexity index R, which can potentially be exploited for prediction, has a similar meaning to the Kolmogorov complexity (calculated from the Lempel–Ziv complexity), and is an appropriate measure of a series' complexity. The proposed method is used to research the complexity of the world's major capital markets. None of these markets are completely random, and they have different degrees of complexity, both over the entire length of their time series and at a level of detail. However, developing markets differ significantly from mature markets. Specifically, the complexity of mature stock markets is stronger and more stable over time, whereas developing markets exhibit relatively low and unstable complexity over certain time periods, implying a stronger long-term price memory process

Unraveling chaotic attractors by complex networks and measurements of stock market complexity.

Science.gov (United States)

Cao, Hongduo; Li, Ying

2014-03-01

We present a novel method for measuring the complexity of a time series by unraveling a chaotic attractor modeled on complex networks. The complexity index R, which can potentially be exploited for prediction, has a similar meaning to the Kolmogorov complexity (calculated from the Lempel-Ziv complexity), and is an appropriate measure of a series' complexity. The proposed method is used to research the complexity of the world's major capital markets. None of these markets are completely random, and they have different degrees of complexity, both over the entire length of their time series and at a level of detail. However, developing markets differ significantly from mature markets. Specifically, the complexity of mature stock markets is stronger and more stable over time, whereas developing markets exhibit relatively low and unstable complexity over certain time periods, implying a stronger long-term price memory process.

The presentation and management of complex female genital malformations.

Science.gov (United States)

Acién, Pedro; Acién, Maribel

2016-01-01

Common uterine anomalies are important owing to their impact on fertility, and complex mesonephric anomalies and certain Müllerian malformations are particularly important because they cause serious clinical symptoms and affect woman's quality of life, in addition to creating fertility problems. In these cases of complex female genital tract malformations, a correct diagnosis is essential to avoid inappropriate and/or unnecessary surgery. Therefore, acquiring and applying the appropriate embryological knowledge, management and therapy is a challenge for gynaecologists. Here, we considered complex malformations to be obstructive anomalies and/or those associated with cloacal and urogenital sinus anomalies, urinary and/or extragenital anomalies, or other clinical implications or symptoms creating a difficult differential diagnosis. A diligent and comprehensive search of PubMed and Scopus was performed for all studies published from 1 January 2011 to 15 April 2015 (then updated up to September 2015) using the following search terms: 'management' in combination with either 'female genital malformations' or 'female genital tract anomalies' or 'Müllerian anomalies'. The MeSH terms 'renal agenesis', 'hydrocolpos', 'obstructed hemivagina' 'cervicovaginal agenesis or atresia', 'vaginal agenesis or atresia', 'Herlyn-Werner-Wunderlich syndrome', 'uterine duplication' and 'cloacal anomalies' were also used to compile a list of all publications containing these terms since 2011. The basic embryological considerations for understanding female genitourinary malformations were also revealed. Based on our experience and the updated literature review, we studied the definition and classification of the complex malformations, and we analysed the clinical presentation and different therapeutic strategies for each anomaly, including the embryological and clinical classification of female genitourinary malformations. From 755 search retrieved references, 230 articles were analysed and

Fuzzy implicative hyper BCK-ideals of hyper BCK-algebras

OpenAIRE

Jun, Young Bae; Shim, Wook Hwan

2002-01-01

We consider the fuzzification of the notion of implicative hyper BCK-ideals, and then investigate several properties. Using the concept of level subsets, we give a characterization of a fuzzy implicative hyper BCK-ideal. We state a relation between a fuzzy hyper BCK-ideal and a fuzzy implicative hyper BCK-ideal. We establish a condition for a fuzzy hyper BCK-ideal to be a fuzzy implicative hyper BCK-ideal. Finally, we introduce the notion of hyper homomorphisms of hyper ...

Encapsulation of ferro- and ferricyanide complexes inside ZSM-5 zeolite synthesized from rice straw: Implications for synthesis of Prussian blue pigment

Energy Technology Data Exchange (ETDEWEB)

Ali, Ibraheem O.; Salama, Tarek M., E-mail: tm_salama@yahoo.com; Thabet, Mohamed S.; El-Nasser, Karam S.; Hassan, Ali M.

2013-06-15

Encapsulation of [Fe(CN){sub 6}]{sup 4−} and [Fe(CN){sub 6}]{sup 3−} complexes in the intracrystalline pores of ZSM-5 zeolite, Fe{sup II}L/Z and Fe{sup III}L/Z respectively, by the zeolite synthesis method was reported. The modified zeolites were characterized by powder XRD, FT-IR and UV–vis spectroscopy. The nitrogen adsorption isotherms allow for the evaluation of pore structure of the complex-modified zeolites, whereas the thermal analysis (TGA/DTA) measurements provide insight into the decomposition products of the immobilized complexes. The modified zeolites exhibited smaller pore volumes and surface areas as compared with those of unpromoted ZSM-5, suggesting the inclusion of iron cyanides inside the interconnecting channels of ZSM-5. While the ferricyanide complex enhanced the formation of highly crystalline zeolite, the ferrocyanide one resulted in a lesser effect. The electronic spectra of the colloidal species developed when Fe{sup III}L/Z brought in contact with an aqueous solution of [Fe(CN){sub 6}]{sup 3−} exhibit absorptions attributed to CN{sup −} → iron charge-transfer. New bands at 294 and 319 nm due to d–d transitions of Fe{sup III} tetrahedral monomeric moieties were emitted concurrently under successive adsorption of [Fe(CN){sub 6}]{sub aq}{sup 3−} over Fe{sup III}L/Z, along with a broad band at 555 nm assigned to polymeric [Fe{sup II}–C–N–Fe{sup III}] of Prussian blue (PB). The FT-IR spectra of Fe{sup III/II}L/Z devoted to the adsorption of an aqueous solution of [Fe(CN){sub 6}]{sup 3−} showed a band at 2092 cm{sup −1} assigned to the C–N stretch in the Fe{sup II}–CN–Fe{sup III} linkages. The vibrations attributable to Fe–O–Si bonding along with hydrocarbon and nitroprusside appeared only in the spectrum of Fe{sup III}L/Z, thus was found to be strong evidence for the mutual interaction between [Fe(CN){sub 6}]{sup 3−} and the latter sample. - Highlights: • We synthesized ferrous and ferric cyanide

Estrogen and progesterone signalling in the normal breast and its implications for cancer development.

Science.gov (United States)

Hilton, Heidi N; Clarke, Christine L; Graham, J Dinny

2018-05-05

The ovarian hormones estrogen and progesterone are master regulators of the development and function of a broad spectrum of human tissues, including the breast, reproductive and cardiovascular systems, brain and bone. Acting through the nuclear estrogen (ER) and progesterone receptors (PR), both play complex and essential coordinated roles in the extensive development of the lobular alveolar epithelial structures of the normal breast during puberty, the normal menstrual cycle and pregnancy. The past decade has seen major advances in understanding the mechanisms of action of estrogen and progesterone in the normal breast and in the delineation of the complex hierarchy of cell types regulated by ovarian hormones in this tissue. There is evidence for a role for both ER and PR in driving breast cancer, and both are favourable prognostic markers with respect to outcome. In this review, we summarize current knowledge of the mechanisms of action of ER and PR in the normal breast, and implications for the development and management of breast cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

The Sheltering of Unwanted Cattle, Experiences in India and Implications for Cattle Industries Elsewhere.

Science.gov (United States)

Kennedy, Uttara; Sharma, Arvind; Phillips, Clive J C

2018-04-26

Reverence for the cow has been a centerpiece of Hindu culture, the roots of which can be traced back to the Indus Valley Civilization around 3000 BCE. Historical and anthropological literature demonstrates how over the millennia the animal’s status as a religious symbol steadily increased and the concept of its sanctity grew in complexity, becoming deeply entrenched and assuming a core identity of the religion. The cow has also been used as a symbol of political opposition to external influences and invading powers. Nowhere else in the world has an animal maintained such divine significance into modern day. This literature review explores the interplay of complex cultural, religious, social and political factors that led to the phenomenon of the sacred cow, a ban on its slaughter and the advent of the modern gaushala. The review also discusses the moral implications of preservation of animal life past their commercial use, the impact on their welfare and need for objectively assessing whether there is a place for such strategies in other animal industries worldwide.

Identification of the first small-molecule ligand of the neuronal receptor sortilin and structure determination of the receptor–ligand complex

Energy Technology Data Exchange (ETDEWEB)

Andersen, Jacob Lauwring, E-mail: jla@mb.au.dk [Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus C (Denmark); Schrøder, Tenna Juul; Christensen, Søren [H. Lundbeck A/S, Ottiliavej 9, 2500 Valby (Denmark); Strandbygård, Dorthe [Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus C (Denmark); Pallesen, Lone Tjener [Aarhus University, Ole Worms Allé 3, 8000 Aarhus C (Denmark); García-Alai, Maria Marta [Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus C (Denmark); Lindberg, Samsa; Langgård, Morten; Eskildsen, Jørgen Calí; David, Laurent; Tagmose, Lena; Simonsen, Klaus Baek; Maltas, Philip James; Rønn, Lars Christian Biilmann; Jong, Inge E. M. de; Malik, Ibrahim John; Egebjerg, Jan; Karlsson, Jens-Jacob [H. Lundbeck A/S, Ottiliavej 9, 2500 Valby (Denmark); Uppalanchi, Srinivas; Sakumudi, Durga Rao; Eradi, Pradheep [GVK BioScience, Plot No. 28 A, IDA Nacharam, Hyderabad 500 076 (India); Watson, Steven P., E-mail: jla@mb.au.dk [H. Lundbeck A/S, Ottiliavej 9, 2500 Valby (Denmark); Thirup, Søren, E-mail: jla@mb.au.dk [Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus C (Denmark)

2014-02-01

The identification of the first small-molecule ligand of the neuronal receptor sortilin and structure determination of the receptor–ligand complex are reported. Sortilin is a type I membrane glycoprotein belonging to the vacuolar protein sorting 10 protein (Vps10p) family of sorting receptors and is most abundantly expressed in the central nervous system. Sortilin has emerged as a key player in the regulation of neuronal viability and has been implicated as a possible therapeutic target in a range of disorders. Here, the identification of AF40431, the first reported small-molecule ligand of sortilin, is reported. Crystals of the sortilin–AF40431 complex were obtained by co-crystallization and the structure of the complex was solved to 2.7 Å resolution. AF40431 is bound in the neurotensin-binding site of sortilin, with the leucine moiety of AF40431 mimicking the binding mode of the C-terminal leucine of neurotensin and the 4-methylumbelliferone moiety of AF40431 forming π-stacking with a phenylalanine.

Identification of the first small-molecule ligand of the neuronal receptor sortilin and structure determination of the receptor–ligand complex

International Nuclear Information System (INIS)

Andersen, Jacob Lauwring; Schrøder, Tenna Juul; Christensen, Søren; Strandbygård, Dorthe; Pallesen, Lone Tjener; García-Alai, Maria Marta; Lindberg, Samsa; Langgård, Morten; Eskildsen, Jørgen Calí; David, Laurent; Tagmose, Lena; Simonsen, Klaus Baek; Maltas, Philip James; Rønn, Lars Christian Biilmann; Jong, Inge E. M. de; Malik, Ibrahim John; Egebjerg, Jan; Karlsson, Jens-Jacob; Uppalanchi, Srinivas; Sakumudi, Durga Rao; Eradi, Pradheep; Watson, Steven P.; Thirup, Søren

2014-01-01

The identification of the first small-molecule ligand of the neuronal receptor sortilin and structure determination of the receptor–ligand complex are reported. Sortilin is a type I membrane glycoprotein belonging to the vacuolar protein sorting 10 protein (Vps10p) family of sorting receptors and is most abundantly expressed in the central nervous system. Sortilin has emerged as a key player in the regulation of neuronal viability and has been implicated as a possible therapeutic target in a range of disorders. Here, the identification of AF40431, the first reported small-molecule ligand of sortilin, is reported. Crystals of the sortilin–AF40431 complex were obtained by co-crystallization and the structure of the complex was solved to 2.7 Å resolution. AF40431 is bound in the neurotensin-binding site of sortilin, with the leucine moiety of AF40431 mimicking the binding mode of the C-terminal leucine of neurotensin and the 4-methylumbelliferone moiety of AF40431 forming π-stacking with a phenylalanine

A Dynamic Intelligent Decision Approach to Dependency Modeling of Project Tasks in Complex Engineering System Optimization

Directory of Open Access Journals (Sweden)

Tinggui Chen

2013-01-01

Full Text Available Complex engineering system optimization usually involves multiple projects or tasks. On the one hand, dependency modeling among projects or tasks highlights structures in systems and their environments which can help to understand the implications of connectivity on different aspects of system performance and also assist in designing, optimizing, and maintaining complex systems. On the other hand, multiple projects or tasks are either happening at the same time or scheduled into a sequence in order to use common resources. In this paper, we propose a dynamic intelligent decision approach to dependency modeling of project tasks in complex engineering system optimization. The approach takes this decision process as a two-stage decision-making problem. In the first stage, a task clustering approach based on modularization is proposed so as to find out a suitable decomposition scheme for a large-scale project. In the second stage, according to the decomposition result, a discrete artificial bee colony (ABC algorithm inspired by the intelligent foraging behavior of honeybees is developed for the resource constrained multiproject scheduling problem. Finally, a certain case from an engineering design of a chemical processing system is utilized to help to understand the proposed approach.

The orbital ground state of the azide-substrate complex of human heme oxygenase is an indicator of distal H-bonding: Implications for the enzyme mechanism‡

Science.gov (United States)

Ogura, Hiroshi; Evans, John P.; Peng, Dungeng; Satterlee, James D.; de Montellano, Paul R. Ortiz; Mar, Gerd N. La

2009-01-01

The active site electronic structure of the azide complex of substrate-bound human heme oxygenase-1, (hHO) has been investigated by 1H NMR spectroscopy to shed light on the orbital/spin ground state as an indicator of the unique distal pocket environment of the enzyme. 2D 1H NMR assignments of the substrate and substrate-contact residue signals reveal a pattern of substrate methyl contact shifts, that places the lone iron π-spin in the dxz orbital, rather than the dyz orbital found in the cyanide complex. Comparison of iron spin relaxivity, magnetic anisotropy and magnetic susceptibilities argues for a low-spin, (dxy)2(dyz,dxz)3, ground state in both azide and cyanide complexes. The switch from singly-occupied dyz for the cyanide to dxz for the azide complex of hHO is shown to be consistent with the orbital hole determined by the azide π-plane in the latter complex, which is ∼90° in-plane rotated from that of the imidazole π-plane. The induction of the altered orbital ground state in the azide relative to the cyanide hHO complex, as well as the mean low-field bias of methyl hyperfine shifts and their paramagnetic relaxivity relative to those in globins, indicate that azide exerts a stronger ligand field in hHO than in the globins, or that the distal H-bonding to azide is weaker in hHO than in globins. The Asp140 → Ala hHO mutant that abolishes activity retains the unusual WT azide complex spin/orbital ground state. The relevance of our findings for other HO complexes and the HO mechanism is discussed. PMID:19243105

Impulse control disorders in Parkinson's disease: clinical characteristics and implications.

Science.gov (United States)

Leeman, Robert F; Potenza, Marc N

2011-04-01

Impulse control disorders (ICDs), specifically those related to excessive gambling, eating, sex and shopping, have been observed in a subset of people with Parkinson's disease (PD). Although some initial case reports claimed that dopamine replacement therapies, particularly dopamine agonists, cause ICDs, more recent, larger and better controlled studies indicate a more complicated picture. While dopamine replacement therapy use is related to ICDs, other vulnerabilities, some related to PD and/or its treatment directly and others seemingly unrelated to PD, have also been associated with ICDs in PD. This suggests a complex etiology with multiple contributing factors. As ICDs occur in a sizable minority of PD patients and can be associated with significant distress and impairment, further investigation is needed to identify factors that can predict who may be more likely to develop ICDs. Clinical implications are discussed and topics for future research are offered.

Implications of deforestation and desertification on sustainable ...

African Journals Online (AJOL)

This paper examines the implications of deforestation and desertification in sustainable agriculture. The problems of deforestation and desertification were examined as they affect land and agricultural productivity. The socio-economic implications of deforestation and desertification in sustainable agriculture were equally ...

Absolute band structure determination on naturally occurring rutile with complex chemistry: Implications for mineral photocatalysis on both Earth and Mars

Science.gov (United States)

Li, Yan; Xu, Xiaoming; Li, Yanzhang; Ding, Cong; Wu, Jing; Lu, Anhuai; Ding, Hongrui; Qin, Shan; Wang, Changqiu

2018-05-01

Rutile is the most common and stable form of TiO2 that ubiquitously existing on Earth and other terrestrial planets like Mars. Semiconducting mineral such as rutile-based photoredox reactions have been considered to play important roles in geological times. However, due to the inherent complexity in chemistry, the precision determination on band structure of natural rutile and the theoretical explanation on its solar-driven photochemistry have been hardly seen yet. Considering the multiple minor and trace elements in natural rutile, we firstly obtained the single-crystal crystallography, mineralogical composition and defects characteristic of the rutile sample by using both powder and single crystal X-ray diffraction, electron microprobe analysis and X-ray photoelectron spectroscopy. Then, the band gap was accurately determined by synchrotron-based O K-edge X-ray absorption and emission spectra, which was firstly applied to natural rutile due to its robustness on compositions and defects. The absolute band edges of the rutile sample was calculated by considering the electronegativity of the atoms, band gap and point of zero charge. Besides, after detecting the defect energy levels by photoluminescence spectra, we drew the schematic band structure of natural rutile. The band gap (2.7 eV) of natural rutile was narrower than that of synthetic rutile (3.0 eV), and the conduction and valence band edges of natural rutile at pH = pHPZC were determined to be -0.04 V and 2.66 V (vs. NHE), respectively. The defect energy levels located at nearly the middle position of the forbidden band. Further, we used theoretical calculations to verify the isomorphous substitution of Fe and V for Ti gave rise to the distortion of TiO6 octahedron and created vacancy defects in natural rutile. Based on density functional theory, the narrowed band gap was interpreted to the contribution of Fe-3d and V-3d orbits, and the defect energy state was formed by hybridization of O-2p and Fe/V/Ti-3d