Triad

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Triad

  • case-parent triad
  • catalytic triad
  • cognitive triad

  • Terms modified by Triad

  • triad data

  • Selected Abstracts


    Investing time in health: do socioeconomically disadvantaged patients spend more or less extra time on diabetes self-care?

    HEALTH ECONOMICS, Issue 6 2009
    Susan L. Ettner
    Abstract Background: Research on self-care for chronic disease has not examined time requirements. Translating Research into Action for Diabetes (TRIAD), a multi-site study of managed care patients with diabetes, is among the first to assess self-care time. Objective: To examine associations between socioeconomic position and extra time patients spend on foot care, shopping/cooking, and exercise due to diabetes. Data: Eleven thousand nine hundred and twenty-seven patient surveys from 2000 to 2001. Methods: Bayesian two-part models were used to estimate associations of self-reported extra time spent on self-care with race/ethnicity, education, and income, controlling for demographic and clinical characteristics. Results: Proportions of patients spending no extra time on foot care, shopping/cooking, and exercise were, respectively, 37, 52, and 31%. Extra time spent on foot care and shopping/cooking was greater among racial/ethnic minorities, less-educated and lower-income patients. For example, African-Americans were about 10 percentage points more likely to report spending extra time on foot care than whites and extra time spent was about 3,min more per day. Discussion: Extra time spent on self-care was greater for socioeconomically disadvantaged patients than for advantaged patients, perhaps because their perceived opportunity cost of time is lower or they cannot afford substitutes. Our findings suggest that poorly controlled diabetes risk factors among disadvantaged populations may not be attributable to self-care practices. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Explanatory models in the interpretations of clinical features of dental patients within a university dental education setting

    EUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 1 2002
    Gerardo Maupome
    Clinicians may acquire biased perceptions during their dental education that can affect decisions about treatment/management of dental decay. This study established explanatory models used by students to interpret clinical features of patients. It employed a stereotypical dental patient under standardised consultation conditions to identify the interpretation of oral health/disease features in the eyes of student clinicians. The study aimed to establish the perceptions of the patient as a client of the university dental clinic, as seen through the ideological lens of a formal Dental Education system. The discourse during simulated clinical consultations was qualitatively analysed to interpret values and concepts relevant to the assessment of restorative treatment needs and oral health status. Three constructs during the consultation were identified: the Dual Therapeutic Realms, the Choices Underlying Treatment Options, and the High-Risk Triad. Comparing these discourse components, the Patient Factors of the Bader and Shugars model for treatment decisions supported the existence of a core set of themes. It was concluded that certain consultation circumstances influenced the adequacy of diagnostic strategies, mainly by introducing loosely defined but highly specific socio-cultural biases ingrained in the Dental Education concepts and diagnostic/treatment needs systems. [source]


    The Chemistry of Technetium,Water Complexes within the Manganese Triad: Challenges and Perspectives

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2009
    Roger Alberto
    Abstract The chemistry of technetium is essentially driven by radiopharmaceutical applications. These comprise the syntheses of novel complexes but, moreover, the combination of targeting biomolecules with metal complexes. Aqua ions are especially convenient for facilitatating the introduction of metal cations into biomolecules, but are nonexistent for Tc and Re in the Mn triad. This microreview will discuss the chemistry of those Tc complexes that contain H2O as ligands. Special attention will be payed to organometallic aqua ions, i.e. complexes that are typically organometallic with water as ligand. Of particular interest is the coordination chemistry of [M(OH2)3(CO)3]+ (M = Mn, Tc, Re) complexes in water since it is the origin of the widely applied radiopharmaceutical research with 99mTc and 188Re. The chemistry of organometallic aqua ions is not confined to Werner-type ligands, hence, a further emphasis will be placed on pure organometallic chemistry in water.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


    A Novel Bis(zinc,porphyrin),Oxoporphyrinogen Donor,Acceptor Triad: Synthesis, Electrochemical, Computational and Photochemical Studies

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2006
    Jonathan P. Hill
    Abstract The first example of a porphyrin-quinonoid donor,acceptor triad featuring (tetraphenylporphinato)zinc(II) moieties covalently attached to an oxoporphyrinogen through its macrocyclic nitrogen atoms is reported. This arrangement of chromophores results in an interesting interplay between the electron-donating zinc,porphyrin(s) and the electron/energy accepting oxoporphyrinogen. The optical absorption of the triad reveals features corresponding to both the donor and acceptor entities. The geometry and electronic structure of the triad deduced from B3LYP/3-21G(*) calculations reveal an absence of inter-chromophoric interactions and localization of the HOMO on one zinc,porphyrin group and the LUMO on the oxoporphyrinogen scaffold. The electrochemical redox states of the triad were established from a comparative electrochemistry of the triad and the reference compounds. Both steady-state and time-resolved emission studies revealed quenching of the singlet excited state of zinc,porphyrin in the triad, and the free-energy calculations performed using Weller's approach indicate the possibility of electron transfer from the singlet excited zinc,porphyrin group to the oxoporphyrinogen in polar solvents. Time-resolved fluorescence studies reveal excited state energy transfer from zinc,porphyrin to oxoporphyrinogen in nonpolar solvents, while nanosecond transient absorption studies combined with time-resolved fluorescence studies in polar solvents are indicative of the occurrence of photoinduced charge separation from the singlet excited zinc,porphyrin to the oxoporphyrinogen. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]


    The dark triad: Facilitating a short-term mating strategy in men

    EUROPEAN JOURNAL OF PERSONALITY, Issue 1 2009
    Peter K. Jonason
    Abstract This survey (N,=,224) found that characteristics collectively known as the Dark Triad (i.e. narcissism, psychopathy and Machiavellianism) were correlated with various dimensions of short-term mating but not long-term mating. The link between the Dark Triad and short-term mating was stronger for men than for women. The Dark Triad partially mediated the sex difference in short-term mating behaviour. Findings are consistent with a view that the Dark Triad facilitates an exploitative, short-term mating strategy in men. Possible implications, including that Dark Triad traits represent a bundle of individual differences that promote a reproductively adaptive strategy are discussed. Findings are discussed in the broad context of how an evolutionary approach to personality psychology can enhance our understanding of individual differences. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Practical use of the International Olympic Committee Medical Commission position stand on the female athlete triad: A case example

    INTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2006
    Roberta Trattner Sherman PhD
    Abstract The female athlete triad consists of the interrelated problems of disordered eating, amenorrhea, and osteoporosis, and it is believed to affect female athletes in all sports and at all levels of competition. Objective: The current article highlights the Position Stand on the Female Athlete Triad of the International Olympic Committee's Medical Commission (IOCMC). Method: The literature related to disordered eating, energy availability, amenorrhea, and bone loss in athletes is briefly reviewed. A hypothetical case is presented to illustrate some of the common issues and problems encountered when working with athletes affected by the triad, such as the effect of weight on performance in "thin" sports, coach involvement, sport participation by symptomatic athletes, and treatment resistance/motivation. Results: Strategies recommended by the position stand for managing those issues and problems are presented regarding the referral, evaluation, and treatment phases of the management process. Conclusion: Implications of the position stand are discussed in terms of the IOCMC's endorsement of the athlete's health being primary to her performance. © 2006 by Wiley Periodicals, Inc., Int J Eat Disord, 2006 [source]


    Degradation of repaired denture base materials in simulated oral fluid

    JOURNAL OF ORAL REHABILITATION, Issue 3 2000
    C.-T. Lin
    This in vitro study evaluates the degradation of repaired denture bases upon immersion in a simulated oral fluid. Denture base materials (Luciton 199®), after being repaired by Repair Material® and Triad®, using three different joint surface designs (butt, round and 45 ° bevel), were immersed onto 99·5 vol.% ethanol/water solution (with similar solubility parameter) for various amounts of time (0,72 h). The flexural loads of the six combination of groups were measured by the three-point bending tests using a universal testing machine. Acoustic emission (AE) during sample fracturing were processed using the MISTRA 2001 system. The fracture pattern and surface details of the interface were examined with a scanning electronic microscope (SEM). Data were analysed using three-way anova and Tukey LSD tests. SEM micrographs of the fracture interface were used to differentiate the fracture mode. The flexural loads (2·72±0·51 Kgf) of the round joint specimens were significantly higher (P<0·05) than those (butt: 1·66±0·38 Kgf, 45 ° bevel: 1·93±0·41 Kgf) of the other two designs. This corresponds to the microscopic examination in which more cohesive failure mode was found for the round joint group after storage. The flexural loads (2·54±0·39 Kgf) of the specimens repaired with Triad® were significantly higher (P<0·05) than those (1·59±0·40 Kgf) of specimens repaired with Repair Material®. Significant progressive reduction of the flexural load and/or AE signals of the specimens was noted in proportion to the length of time of the immersion in the simulated oral fluid. Mechanical strength of a denture base repaired with a round joint design and light-cured material is significantly higher after immersion in simulated oral fluid. [source]


    Triad of polar residues implicated in pH specificity of acidic mammalian chitinase

    PROTEIN SCIENCE, Issue 3 2009
    Andrea M. Olland
    Abstract Acidic mammalian chitinase (AMCase) is a mammalian chitinase that has been implicated in allergic asthma. One of only two active mammalian chinases, AMCase, is distinguished from other chitinases by several unique features. Here, we present the novel structure of the AMCase catalytic domain, both in the apo form and in complex with the inhibitor methylallosamidin, determined to high resolution by X-ray crystallography. These results provide a structural basis for understanding some of the unique characteristics of this enzyme, including the low pH optimum and the preference for the ,-anomer of the substrate. A triad of polar residues in the second-shell is found to modulate the highly conserved chitinase active site. As a novel target for asthma therapy, structural details of AMCase activity will help guide the future design of specific and potent AMCase inhibitors. [source]


    Expediting sustainable brownfields redevelopment by applying Triad using the membrane interface probe

    REMEDIATION, Issue 4 2010
    Maria D. Watt
    Redevelopment and reuse plans are often based upon an expedited delineation and remediation life cycle, since delayed reuse usually has economic consequences. It has also become increasingly important to utilize sustainable practices to achieve investigation and remediation goals. In this article, the Triad approach is used to expedite the delineation of a source area within a municipal landfill to complete the remedial effort prior to construction of an urban civic center. The Triad approach uses the three elements of systematic project planning, dynamic work strategy, and real-time measurement to expedite site characterization (Interstate Technology and Regulatory Council, 2003). In this article, the Triad sampling strategy consisted of two phases. The first phase included in situ screening of soil and groundwater using the membrane interface probe (MIP), and the second phase included confirmatory sampling via vertical profiles in the soil and groundwater. This study found that, using the MIP in a dynamic sampling strategy, a critical element of the Triad approach, combined with the proper placement of confirmatory samples, significantly reduced overall project cost and will expedite the site redevelopment. The use of the Triad approach also contributed to the integration of green and sustainable practices into the project. © 2010 Wiley Periodicals, Inc. [source]


    Triad case study: Marine Corps Base Camp Pendleton

    REMEDIATION, Issue 1 2004
    Adrianne V. Saboya
    The U.S. Navy Public Works Center (PWC) Environmental Department, San Diego, California, is home to the Navy West Coast Site Characterization and Analysis Penetrometer System (SCAPS). SCAPS has been extensively used at several Navy sites since 1995 to provide real-time, high-density data sets. The U.S. Environmental Protection Agency's Triad approach provided an ideal framework for optimizing the use of the Navy SCAPS during a volatile organic compound (VOC) source investigation at Installation Restoration Site 1114 at Marine Corps Base Camp Pendleton. All three elements of Triad,systematic planning, dynamic work strategy, and use of real-time measurement tools,were implemented to manage decision uncertainty and expedite the site management process. The investigation was conducted using the Navy SCAPS, outfitted with a cone penetrometer, membrane interface probe, and a direct sampling ion trap mass spectrometry detector, which allowed for real- time collection of over 690 feet of continuous lithologic information and VOC concentration data. These data were used collaboratively with 24-hour turnaround US EPA 8260B VOC groundwater results from temporary direct- push wells to support the conclusion of a limited source area. Implementation of the Triad approach for this investigation provided an expedited high-density data set and a refined conceptual site model (CSM) in real time that resulted in cost savings estimated at $2.5M and reduction of the site characterization and cleanup schedule by approximately three years. This project demonstrates how the US EPA's Triad approach can be applied to streamline the site characterization and cleanup process while appropriately managing decision uncertainty in support of defensible site decisions. © 2004 Wiley Periodicals, Inc. [source]


    Triad of Columnar Cell Alteration, Lobular Carcinoma in Situ, and Tubular Carcinoma of the Breast

    THE BREAST JOURNAL, Issue 2 2005
    Sunati Sahoo MD
    Abstract: Columnar cell alteration in the breast encompasses a spectrum of pathologic changes ranging from simple columnar cell change to more complex columnar cell hyperplasia with and without atypia to in situ carcinoma, often with a micropapillary architecture. For reasons that remain unclear, the columnar cell lesions are associated with tubular carcinomas and lobular carcinoma in situ. Therefore it is important to be familiar with the spectrum of changes and the associated lesions, especially in breast core biopsies for further management., [source]


    Trade in the Triad: how easy is the access to large markets?,

    CANADIAN JOURNAL OF ECONOMICS, Issue 4 2005
    Lionel Fontagné
    We investigate overall and industry-level trends of bilateral trade openness and provide explanations for those using proxies for bilateral observed protection (tariffs and NTBs), home bias of consumers, product differentiation, and levels of FDI. The explanations related to actual protection, home bias and substitutability of goods put together explain a large part of the border effect between blocs of the Triad, although they do not explain the whole of the border effect puzzle. JEL classification: F12, F15 Commerce dans la Triade : jusqu'à quel point l'accès aux grands marchés est il facile?, Cet article mesure le niveau d'intégration commerciale entre les pays de l'UE, le Japon et les Etats-Unis (la Triade) en utilisant l'effet des frontières nationales sur le commerce international. Nous étudions le niveau et l'évolution du degré d'ouverture bilatéral ainsi que les différentes explications possibles des effets frontière estimés qui sont testées à l'aide de variables capturant la protection (tarifs et BNTs), le biais domestique des consommateurs, le degré de différenciation des produits et les niveaux d'IDE bilatéraux. Les explications liées à la protection, au biais domestique et à la substituabilité entre produits, considérées ensemble, expliquent une bonne partie de l'effet frontière entre pays de la Triade, même si elles n'expliquent pas la totalité de l'énigme. [source]


    Mutational Studies Confirm the Catalytic Triad in the Human Selenoenzyme Thioredoxin Reductase Predicted by Molecular Modeling

    CHEMBIOCHEM, Issue 11 2006
    Stephan Gromer Dr.
    Three's company. Site-directed mutagenesis of Glu477 of the human thioredoxin reductase (see figure) to glutamine, alanine, or lysine led to a significant drop in enzymatic activity. This study reinforces previous theoretical calculations which suggested that a swapping catalytic triad exists in the active site of this enzyme. [source]


    Mesogenic V-Like Triad on the Basis of 3,4-Dihydroxybenzophenone.

    CHEMINFORM, Issue 25 2003
    E. V. Demina
    Abstract For Abstract see ChemInform Abstract in Full Text. [source]


    Dopamine, Morphine, and Nitric Oxide: An Evolutionary Signaling Triad

    CNS: NEUROSCIENCE AND THERAPEUTICS, Issue 3 2010
    George B. Stefano
    Morphine biosynthesis in relatively simple and complex integrated animal systems has been demonstrated. Key enzymes in the biosynthetic pathway have also been identified, that is, CYP2D6 and COMT. Endogenous morphine appears to exert highly selective actions via novel mu opiate receptor subtypes, that is, mu3,-4, which are coupled to constitutive nitric oxide release, exerting general yet specific down regulatory actions in various animal tissues. The pivotal role of dopamine as a chemical intermediate in the morphine biosynthetic pathway in plants establishes a functional basis for its expansion into an essential role as the progenitor catecholamine signaling molecule underlying neural and neuroendocrine transmission across diverse animal phyla. In invertebrate neural systems, dopamine serves as the preeminent catecholamine signaling molecule, with the emergence and limited utilization of norepinephrine in newly defined adaptational chemical circuits required by a rapidly expanding set of physiological demands, that is, motor and motivational networks. In vertebrates epinephrine, emerges as the major end of the catecholamine synthetic pathway consistent with a newly incorporated regulatory modification. Given the striking similarities between the enzymatic steps in the morphine biosynthetic pathway and those driving the evolutionary adaptation of catecholamine chemical species to accommodate an expansion of interactive but distinct signaling systems, it is our overall contention that the evolutionary emergence of catecholamine systems required conservation and selective "retrofit" of specific enzyme activities, that is, COMT, drawn from cellular morphine expression. Our compelling hypothesis promises to initiate the reexamination of clinical studies, adding new information and treatment modalities in biomedicine. [source]


    Perylene,Oligothiophene,Perylene Triads for Photovoltaic Applications

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 17 2005
    Jens Cremer
    Abstract A series of novel acceptor,donor,acceptor triad systems, consisting of head-to-tail-coupled oligo(3-hexylthiophene)s integrated between two terminal perylenemonoimides are described. These hybrid molecules, which differ by the length of the oligothiophene units from a quaterthiophene up to a dodecithiophene were synthesized by an effective palladium-catalyzed Ullmann-type homo-coupling reaction in good yields. The optical and electrochemical properties of these compounds were determined, and on the basis of this series structure-property relationships have been established which provide vital information for the fabrication of the corresponding photovoltaic devices. Because the synthesized perylenyl-oligothiophenes distinguish themselves by a high absorption between 300 and 550 nm and an almost complete fluorescence quenching of the perylene acceptor, they meet the requirements for organic solar cells. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]


    Triads in Services Outsourcing: Bridge, Bridge Decay and Bridge Transfer,

    JOURNAL OF SUPPLY CHAIN MANAGEMENT, Issue 3 2009
    MEI LI
    Typically, a triad of actors is involved in any outsourcing situation: the buyer, the supplier and the buyer's customer. In manufacturing, the buyer acts as a bridge between its supplier and its customer and maintains this bridge position before, during and after the outsourcing. However, in services, the relationship structures among the three actors change before, during and after the outsourcing. Before outsourcing (i.e., during the contract negotiation stage), the buyer is the "bridge" between its supplier and its customer. During implementation, this bridge position begins to "decay" as its supplier comes in direct contact with the buyer's customer. Post-implementation, the bridge position is intended to be "transferred" to the supplier. However, if left unmanaged, this state of transferred bridge position has serious performance implications for the buyer. The supplier is now the bridge and thus enjoys the leverage inherent in being a bridge. This point has been missed in many services outsourcing ventures by major multinational corporations. To mitigate this effect, we propose that the buyer should continue to actively interact with its customer and closely monitor the supplier in order to prevent the supplier from solidifying its bridge position. [source]


    Using Case-parent Triads to Estimate Relative Risks Associated with a Candidate Haplotype

    ANNALS OF HUMAN GENETICS, Issue 3 2009
    Min Shi
    Summary Estimating haplotype relative risks in a family-based study is complicated by phase ambiguity and the many parameters needed to quantify relative risks for all possible diplotypes. This problem becomes manageable if a particular haplotype has been implicated previously as relevant to risk. We fit log-linear models to estimate the risks associated with a candidate haplotype relative to the aggregate of other haplotypes. Our approach uses existing haplotype-reconstruction algorithms but requires assumptions about the distribution of haplotypes among triads in the source population. We consider three levels of stringency for those assumptions: Hardy-Weinberg Equilibrium (HWE), random mating, and no assumptions at all. We assessed our method's performance through simulations encompassing a range of risk haplotype frequencies, missing data patterns, and relative risks for either offspring or maternal genetic effects. The unconstrained model provides robustness to bias from population structure but requires excessively large sample sizes unless there are few haplotypes. Assuming HWE accommodates many more haplotypes but sacrifices robustness. The model assuming random mating is intermediate, both in the number of haplotypes it can handle and in robustness. To illustrate, we reanalyze data from a study of orofacial clefts to investigate a 9-SNP candidate haplotype of the IRF6 gene. [source]


    Testing for Genetic Association With Constrained Models Using Triads

    ANNALS OF HUMAN GENETICS, Issue 2 2009
    J. F. Troendle
    Summary It has been shown that it is preferable to use a robust model that incorporated constraints on the genotype relative risk rather than rely on a model that assumes the disease operates in a recessive or dominant fashion. Previous methods are applicable to case-control studies, but not to family based studies of case children along with their parents (triads). We show here how to implement analogous constraints while analyzing triad data. The likelihood, conditional on the parents genotype, is maximized over the appropriately constrained parameter space. The asymptotic distribution for the maximized likelihood ratio statistic is found and used to estimate the null distribution of the test statistics. The properties of several methods of testing for association are compared by simulation. The constrained method provides higher power across a wide range of genetic models with little cost when compared to methods that restrict to a dominant, recessive, or multiplicative model, or make no modeling restriction. The methods are applied to two SNPs on the methylenetetrahydrofolate reductase (MTHFR) gene with neural tube defect (NTD) triads. [source]


    Fullerene Ylidene Malonate Supramolecular Triads.

    CHEMINFORM, Issue 1 2003
    Luigi Garlaschelli
    No abstract is available for this article. [source]


    Intramolecular Energy Transfer in Pyrene,Bodipy Molecular Dyads and Triads

    CHEMISTRY - A EUROPEAN JOURNAL, Issue 24 2005
    Raymond Ziessel Dr.
    Abstract Molecules bearing a 4,4-difluoro-8-(aryl)-1,3,5,7-tetramethyl-2,6-diethyl-4-bora-3a,4a-diaza- s -indacene (bodipy) core and 1-pyrenyl-1-phenyl-4-(1-ethynylpyrene), or 1-phenyl-4-[1-ethynyl-(6-ethynylpyrene)pyrene] units were constructed in a step-by-step procedure based on palladium(0)-promoted cross-coupling reactions with the required preconstructed modules. X-ray structures of single crystals reveal a twisted arrangement of the two chromophores. In one case, an almost perfect orthogonal arrangement is found. These dyes are strongly luminescent in solution and display rich electrochemistry in which all redox processes of the bodipy and pyrene fragments are clearly resolved. The absorption spectra indicate that the bodipy and pyrene chromophores are spectrally isolated, thereby inducing a large "virtual" Stokes shift. The latter is realised by efficient transfer of intramolecular excitation energy by the Förster dipole,dipole mechanism. The rate of energy transfer depends on the structure of the dual-dye system and decreases as the centre-to-centre separation increases. The energy transfer efficiency, however, exceeds 90,% in all cases. The linkage of two pyrene residues by an ethyne group leads to a decrease in the energy-transfer efficiency, with the two polycycles acting as a single chromophore. The directly linked bodipy,pyrene dual dye binds to DNA and operates as an efficient solar concentrator when dispersed in plastic. De nouvelles molécules comprenant un c,ur 4,4-difluoro-8-(aryl)-1,3,5,7-tetramethyl-2,6-diethyl-4-bora-3a,4a-diaza-s-indacene (appelé bodipy) et des fragments 1-pyrènyl, 1-phényl-4-(1-éthynylpyrène), ou 1-phényl-4-[1-éthynyl-(6-éthynylpyrène)pyrène] ont été synthétisées par le biais de couplage croisés entre des modules pré-construits. Ces réactions ont été catalysées par du palladium sous-ligandé dans des conditions anaérobiques. Dans deux cas typiques la structure moléculaire déterminée par diffraction aux rayons X sur monocristal révèle un arrangement quasi perpendiculaire des deux sous-unités bodipy et pyrène. L'ensemble des composés sont très fluorescents en solution et dévoilent une voltammétrie cyclique riche en signaux réversibles. L'ensemble des processus d'oxydation et de réduction localisés sur les sous-unité pyrène et bodipy sont bien résolus. De plus ces deux fragments sont spectroscopiquement différenciées ce qui permet d'obtenir des déplacements de Stokes important lorsque la partie pyrène est excitée et que la fluorescence de la partie bodipy est observée. Le processus responsable de ce phénomène est un transfert d'énergie ayant lieu par résonance (mécanisme dit de Förster par interaction dipôle-dipôle). La vitesse de ce transfert d'énergie dépends de la structure moléculaire et décroît en augmentant la distance ente les deux chromophores. L'efficacité de ce transfert est supérieur à 90,% dans l'ensemble des cas étudiés. Cependant la connexion par une liaison triple des motifs bodipy et pyrène diminue l'efficacité de ce transfert. La molécule comportant un pyrène directement connecté au bodipy se lie fortement à l'ADN et se comporte comme un concentrateur de photons lorsque dispersé dans des plastiques rigides. [source]


    Psychometric evaluation of a measure of Beck's negative cognitive triad for youth: applications for African,American and Caucasian adolescents

    DEPRESSION AND ANXIETY, Issue 4 2005
    Leilani Greening
    Abstract A measure of Beck's negative cognitive triad, the Cognitive Triad for Children (CTI-C), was evaluated for its psychometric properties and utility with a community sample of 880 African,American and Caucasian adolescents. High-school students ranging from 14 to 17 years of age completed the CTI-C, the Children's Depression Inventory (CDI) and the Children's Attributional Style Questionnaire-Revised (CASQ-R) on two occasions 4 months apart. The CTI-C was found to be internally consistent, Cronbach's ,=.90, to have acceptable test-retest reliability, r=.70, and concurrent validity as demonstrated by a significant correlation with the CASQ-R, r=.53. A principal factor analysis with promax rotation did not yield support for Beck's tripartite model of negative cognitions about the self, world, and future but rather yielded three factors with a combination of cognitions from all three domains. African American adolescents who reported more maladaptive cognitions on the CTI-C reported fewer depressive symptoms on the CDI 4 months later compared to their Caucasian counterparts, suggesting some limitation to using the CTI-C to predict depressive symptoms in African,American youth; however, Factor 1 derived from a factor analysis with the sample was more consistent in predicting future symptoms among both African,American and Caucasian adolescents. This factor consisted largely of positively worded items, offering some support for low positive affect as a predictor of depressive symptoms in adolescents. Depression and Anxiety 21:161,169, 2005. © 2005 Wiley-Liss, Inc. [source]


    Cloning and Characterization of the cDNA Encoding the Masquerade-like Serine Proteinase Homologue Gene of the Silkworm, Bombyx mori

    ENTOMOLOGICAL RESEARCH, Issue 3 2002
    Doo-Sang PARK
    ABSTRACT From Bombyx mori larvae, RT-PCR and cDNA library screening isolated masquerade-like serine proteinase homologue cDNA gene, proposed to be related to insect immunity and its characteristics were examined. The isolated gene is composed of 1.3 kb of nucleotide and 420 amino acid residues were encoded. According to the results of database search, the isolated gene showed high sequence homology with Holotrichia and Tenebrio's 45 kDa protein, Drosophila CG5390 gene. Moreover, it is composed of regulatory domain and catalytic domain, which is characteristic of serine proteinase that can be found in the insect immune reaction and embryonic development processes. Enzyme activation site by proteolytic cleavage and the sequence of three amino acids participate in the catalytic triad of enzyme and 14 cystein residues used in disulfide bridges are well conserved with the compared genes. The mRNA expression was increased following E. coli injection and constitutive expression was also observed before injection by Northern blot analysis. [source]


    Changes in Panayiotopoulos syndrome over time

    EPILEPSIA, Issue 2009
    Giuseppe Capovilla
    Summary In its first description (1989), Panayiotopoulos syndrome was defined as an idiopathic epilepsy syndrome with an excellent prognosis, characterized by a clinical ictal triad of nocturnal seizures, tonic deviation of the eyes, and vomiting. The electroencephalographic and clinical features of this condition were highly suggestive of occipital lobe involvement. Subsequently, the concept of this benign age-related focal epilepsy has been expanded over the years, including a wider and larger spectrum of seizure manifestations far beyond the occipital manifestations, and for which the eponym of Panayiotopoulos syndrome (PS) has been adopted. However, many theoretical and practical points, including diagnostic, genetic, and pathophysiologic issues remain still unresolved for PS. [source]


    Sex and the Single Vole: Effects of Social Grouping on Prairie Vole Reproductive Success

    ETHOLOGY, Issue 10 2002
    Karen E. Hodges
    Prairie voles (Microtus ochrogaster) have a mating system that is primarily monogamous with paired males and females together defending breeding space against intruders of either sex. Breeding success may be affected when other adults intrude on the territorial space of pairs. We conducted an experiment to determine the impact of additional members of either sex on reproductive success of pairs. In laboratory arenas, we formed pairs (1F:1M) and two kinds of triad (2F:1M, 1F:2M). Females in pairs had the highest conception rates, litter sizes and survival of litters. Females in 1F:2M groups had slightly reduced litter sizes and reduced numbers of weanlings, and some females had litters sired by both males. Females in 2F:1M groups had low conception rates and the smallest litters, and >35% of their litters suffered infanticide; in no case did both females become pregnant. Throughout the trials, individuals of the sex doubly represented in triads were more likely to die than were individuals of the sex singly represented. We conclude that there may be fitness costs associated with the presence of unrelated supernumerary adults during gestation and lactation. [source]


    The Chemistry of Technetium,Water Complexes within the Manganese Triad: Challenges and Perspectives

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2009
    Roger Alberto
    Abstract The chemistry of technetium is essentially driven by radiopharmaceutical applications. These comprise the syntheses of novel complexes but, moreover, the combination of targeting biomolecules with metal complexes. Aqua ions are especially convenient for facilitatating the introduction of metal cations into biomolecules, but are nonexistent for Tc and Re in the Mn triad. This microreview will discuss the chemistry of those Tc complexes that contain H2O as ligands. Special attention will be payed to organometallic aqua ions, i.e. complexes that are typically organometallic with water as ligand. Of particular interest is the coordination chemistry of [M(OH2)3(CO)3]+ (M = Mn, Tc, Re) complexes in water since it is the origin of the widely applied radiopharmaceutical research with 99mTc and 188Re. The chemistry of organometallic aqua ions is not confined to Werner-type ligands, hence, a further emphasis will be placed on pure organometallic chemistry in water.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


    Effects of maxillary sinus floor elevation surgery on maxillary sinus physiology

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2003
    Nicolaas M. Timmenga
    In a prospective study, the effects of elevation surgery of the maxillary sinus floor on maxillary sinus physiology were assessed. Seventeen consecutive patients without preoperative anamnestic, clinical and radiological signs of maxillary sinusitis underwent sinus floor elevation surgery with iliac crest bone grafts. All patients were subjected to unilateral endoscopic examination of the maxillary sinus, taking of a biopsy specimen from the sinus floor mucosa, and collection of a sinus lavage-fluid aspirate. This triad of evaluations was performed immediately preceding the elevation procedure, and 3 months (at implant insertion) and 9 months (at uncovering of implants) postoperatively. All procedures were performed under general anesthesia. Preoperatively, three out of 17 patients showed pre-existing mucosal pathology endoscopically, while the 3- and 9-month results revealed the presence of mucosal pathology in four and two patients, respectively. The 3-month microbiological evaluation showed a significant increase in cultures with bacterial growth, while the 9-month culture results were comparable to the preoperative status of the maxillary sinus. Morphologically, neither fibrosis nor an altered inflammatory response or thickening of the epithelium and lamina propria was observed postoperatively. The number of goblet cells in the epithelial layer was increased. From this study it is concluded that the effect of maxillary sinus floor elevation surgery with autogenous bone grafts does not appear to have clinical consequences in patients without signs of pre-existing maxillary sinusitis. [source]


    Synthesis and Photophysical Properties of a Pyrazolino[60]fullerene with Dimethylaniline Connected by an Acetylene Linkage

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 10 2006
    Andreas Gouloumis
    Abstract A new triad based on pyrazolino[60]fullerene and a conjugated dimethylaniline group has been synthesized by a copper-free Sonogashira cross-coupling reaction using microwave irradiation as the source of energy. The electrochemical and photophysical properties of the triad were systematically investigated by techniques such as time-resolved fluorescence and transient absorption spectroscopy. Charge separation via the excited singlet state of the C60 moiety was confirmed in polar and nonpolar solvents and competes with triplet formation of the C60 moiety. The charge-separated state persisted for 91 ns. Such long lifetimes are characteristic of long distances between the radical anion of the pyrazolino[60]fullerene derivative and the radical cation of the dimethylaniline moiety. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]


    A Novel Bis(zinc,porphyrin),Oxoporphyrinogen Donor,Acceptor Triad: Synthesis, Electrochemical, Computational and Photochemical Studies

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2006
    Jonathan P. Hill
    Abstract The first example of a porphyrin-quinonoid donor,acceptor triad featuring (tetraphenylporphinato)zinc(II) moieties covalently attached to an oxoporphyrinogen through its macrocyclic nitrogen atoms is reported. This arrangement of chromophores results in an interesting interplay between the electron-donating zinc,porphyrin(s) and the electron/energy accepting oxoporphyrinogen. The optical absorption of the triad reveals features corresponding to both the donor and acceptor entities. The geometry and electronic structure of the triad deduced from B3LYP/3-21G(*) calculations reveal an absence of inter-chromophoric interactions and localization of the HOMO on one zinc,porphyrin group and the LUMO on the oxoporphyrinogen scaffold. The electrochemical redox states of the triad were established from a comparative electrochemistry of the triad and the reference compounds. Both steady-state and time-resolved emission studies revealed quenching of the singlet excited state of zinc,porphyrin in the triad, and the free-energy calculations performed using Weller's approach indicate the possibility of electron transfer from the singlet excited zinc,porphyrin group to the oxoporphyrinogen in polar solvents. Time-resolved fluorescence studies reveal excited state energy transfer from zinc,porphyrin to oxoporphyrinogen in nonpolar solvents, while nanosecond transient absorption studies combined with time-resolved fluorescence studies in polar solvents are indicative of the occurrence of photoinduced charge separation from the singlet excited zinc,porphyrin to the oxoporphyrinogen. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]


    Texas Trooper Uniforms: Assessment of Fabrics, Comfort, and Wear

    FAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 3 2002
    Patricia E. Horridge
    Using the physical dimension triad of Branson and Sweeney's Model for Clothing Comfort as a conceptual framework, the purpose of the study was to examine the effects of cotton/wool fabrics on comfort and wear of trooper uniforms. Participants were 10 troopers recruited for wear- testing uniforms developed in accordance to Texas Department of Public Safety specifications. Trooper shirt and pants fabrics were developed in two fiber contents (80/20 and 70/30 cotton/wool) and tested before and after dry-cleaning. Twenty constructed uniforms and 10 issued uniforms were worn through four wear-refurbishing-dry-cleaning cycles. Surveys and scales were used to gather data during and after wear testing; data were analyzed by t-test and ANOVAs. Branson and Sweeney's comfort model was supported, in part, with person attributes (body weight, hours uniform worn) affecting uniform comfort. Implications are given for fabric producers and garment manufacturers. [source]