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Triple
Terms modified by Triple Selected AbstractsPrevalence of drug resistance and importance of viral load measurements in Honduran HIV-infected patients failing antiretroviral treatmentHIV MEDICINE, Issue 2 2010W Murillo Objective The Honduran HIV/AIDS Program began to scale up access to HIV therapy in 2002. Up to May 2008, more than 6000 patients received combination antiretroviral therapy (cART). As HIV drug resistance is the major obstacle for effective treatment, the purpose of this study was to assess the prevalence of antiretroviral drug resistance in Honduran HIV-1-infected individuals. Methods We collected samples from 138 individuals (97 adults and 41 children) on cART with virological, immunological or clinical signs of treatment failure. HIV-1 pol sequences were obtained using an in-house method. Resistance mutations were identified according to the 2007 International AIDS Society (IAS)-USA list and predicted susceptibility to cART was scored using the anrs algorithm. Results Resistance mutations were detected in 112 patients (81%), 74% in adults and 98% in children. Triple-, dual- and single-class drug resistance was documented in 27%, 43% and 11% of the study subjects, respectively. Multiple logistic regression showed that resistance was independently associated with type of treatment failure [virological failure (odds ratio (OR)=1) vs. immunological failure (OR=0.11; 95% confidence interval (CI) 0.030,0.43) vs. clinical failure (OR=0.037; 95% CI 0.0063,0.22)], route of transmission (OR=42.8; 95% CI 3.73,491), and years on therapy (OR=1.81; 95% CI 1.11,2.93). Conclusion The prevalence of antiretroviral resistance was high in Honduran HIV-infected patients with signs of treatment failure. A majority of study subjects showed dual- or triple-class resistance to nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors and protease inhibitors. Virologically defined treatment failure was a strong predictor of resistance, indicating that viral load testing is needed to correctly identify patients with treatment failure attributable to resistance. [source] Transition in Post-Communist States: Triple or Quadruple?POLITICS, Issue 3 2001Taras Kuzio When the study of transitions moved from Latin America and southern Europe scholars initially assumed that transition in these two regions would be regime-based ,double transitions' of democratisation and marketisation. Gradually, it was accepted by scholars that many post-communist states inherited weak states and institutions, thereby adding a third factor to the transition process of stateness. This ,triple transition' has been largely accepted as sufficient to understand post-communist transitions and, in some cases, includes nationality questions. This article builds on the ,triple transition' by separating the national and stateness questions within its third aspect and argues that although both processes are interlinked they should be nevertheless separated into separate components (democratisation and marketisation are treated separately but are also closely related phenomena). This article argues two points. First, stateness and the nationality question were until recently ignored by scholars because these were not factors in earlier transitions. Secondly, they were ignored because the relationship of nationhood to the civic state is still under-theorised. [source] Attention deficit hyperactivity disorder in pre-school children: current findings, recommended interventions and future directionsCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 6 2009D. Daley Abstract This paper outlines the presentation, aetiology and treatment of attention deficit hyperactivity disorder (ADHD) in pre-school children. A review of current parenting training interventions demonstrates that there is good evidence for their efficacy in reducing symptoms of ADHD in pre-school children, and three interventions are evaluated: The new forest parent training programme (NFPP); the triple P , positive parenting programme and the incredible years parent training programme (IY). The evaluation of the NFPP provides strong evidence demonstrating its effectiveness for pre-school children with ADHD, while the efficacy of the Triple , P and the IY programme have, to date, only been demonstrated on children with conduct problems and co-morbid ADHD. It is suggested that parent training should be the first choice treatment for pre-school children presenting signs of ADHD, and medication introduced only for those children where parent training is not effective. Few moderators of outcome have been identified for these interventions, with the exception of parental ADHD. Barriers to intervention and implementation fidelity will need to be addressed to achieve high levels of attendance, completion and efficacy. The IY programme is a good model for addressing fidelity issues and for overcoming barriers to intervention. The future directions for parent training are also discussed. [source] La2CuS4: A Lanthanum Copper Sulfide with Discrete Anion Triples [S3Cu×××S,S×××CuS 3]12- Based on La4[Cu2S6(S2)].CHEMINFORM, Issue 1 2004Sabine Strobel Abstract For Abstract see ChemInform Abstract in Full Text. [source] Lazy Solid Texture SynthesisCOMPUTER GRAPHICS FORUM, Issue 4 2008Yue Dong Abstract Existing solid texture synthesis algorithms generate a full volume of color content from a set of 2D example images. We introduce a new algorithm with the unique ability to restrict synthesis to a subset of the voxels, while enforcing spatial determinism. This is especially useful when texturing objects, since only a thick layer around the surface needs to be synthesized. A major difficulty lies in reducing the dependency chain of neighborhood matching, so that each voxel only depends on a small number of other voxels. Our key idea is to synthesize a volume from a set of pre-computed 3D candidates, each being a triple of interleaved 2D neighborhoods. We present an efficient algorithm to carefully select in a pre-process only those candidates forming consistent triples. This significantly reduces the search space during subsequent synthesis. The result is a new parallel, spatially deterministic solid texture synthesis algorithm which runs efficiently on the GPU. Our approach generates high resolution solid textures on surfaces within seconds. Memory usage and synthesis time only depend on the output textured surface area. The GPU implementation of our method rapidly synthesizes new textures for the surfaces appearing when interactively breaking or cutting objects. [source] Effects of Kindermusik training on infants' rhythmic enculturationDEVELOPMENTAL SCIENCE, Issue 3 2010David W. Gerry Phillips-Silver and Trainor (2005) demonstrated a link between movement and the metrical interpretation of rhythm patterns in 7-month-old infants. Infants bounced on every second beat of a rhythmic pattern with no auditory accents later preferred to listen to an accented version of the pattern with accents every second beat (duple or march meter), whereas infants bounced on every third beat of the same rhythmic pattern preferred to listen to a version with accents every third beat (triple or waltz meter). The present study compared infants participating in Kindermusik classes with infants not participating in music classes. In Kindermusik classes infants receive enriched experience moving to music. Following Western musical norms, the majority of the music samples in the classes are in duple meter. During the preference test, Kindermusik infants listened longer overall, indicating heightened interest in musical rhythms. Both groups listened longer to the accented version that matched how they had been bounced, but only the Kindermusik group showed a stronger preference in the case of duple bouncing than in the case of triple bouncing. We conclude that musical classes for infants can accelerate the development of culture-specific metrical perception. [source] Ventricular PKC-, and humoral signaling in DOCA-Salt rats treated with labedipinedilol-ADRUG DEVELOPMENT RESEARCH, Issue 3 2003Jwu-Lai Yeh Abstract Effects of oral antihypertensive monotherapy with labedipinedilol-A, labetalol, atenolol, amlodipine, prazosin (20 mg kg,1 day,1), and short-acting nifedipine (3 mg kg,1 day,1) on DOCA-salt-induced translocation of ventricular protein kinase C-,(PKC-,), humoral signaling, and the cardiovascular system were investigated in rats for 4 weeks. The triple blocking activities of labedipinedilol-A (,/,-adrenoceptor blockade and calcium entry blockade) were compared with single blocking activities of selective drugs. Cytosolic PKC-, immunoreactivity was decreased by labedipinedilol-A, short-acting nifedipine, amlodipine, prazosin, labetalol, atenolol, and losartan. Membranous PKC-, immunoreactivity was significantly decreased by labedipinedilol-A, amlodipine, prazosin, labetalol, and atenolol. Labedipinedilol-A and prazosin more potently decreased membranous than cytosolic PKC-, expression. Labedipinedilol-A, labetalol, and atenolol effectively inhibited DOCA-salt-induced increases in angiotensin II (Ang II). All antihypertensive agents reduced endothelin-1 (ET-1) levels in urine and cardiac weight growth. Treatments with labedipinedilol-A, labetalol, atenolol, and amlodipine normalized DOCA-salt-induced ANP increases. Prazosin did not decrease ANP. Short-acting nifedipine elevated ANP. During long-term antihypertensive therapy in DOCA-salt hypertensive rats, single blockade drugs did not fully inhibit ventricular PKC-, translocation or Ang II, ET-1, and ANP humoral signaling. However, triple blockade labedipinedilol-A therapy had a wide range of ,/,-adrenergic receptor and calcium channel inhibitory activities, including diminished reflux tachycardia, inhibition of PKC-, translocation, and reduction of Ang II, ET-1, and ANP formation. Drug Dev. Res. 59:307,315, 2003. 2003 Wiley-Liss, Inc. [source] Profitable self-superparasitism in an infanticidal parasitoid when conspecifics are present: self-superparasitism deters later attackers from probing for infanticideECOLOGICAL ENTOMOLOGY, Issue 6 2005Emi Ito Abstract., 1.,To reveal the profitability of self-superparasitism when conspecifics are present, the total combined fitness returns from the first and second ovipositions under triple parasitism were compared with fitness returns from the first oviposition under double parasitism, using the small brown hopper Laodelphax striatellus and its semi-solitary infanticidal parasitoid Echthrodelphax fairchildii. 2.,The total combined survival rate of the first and second comers under triple parasitism with oviposition intervals of 1/24 h (where 1 and 24 h represent the first-to-second and second-to-third oviposition intervals respectively) was nearly double the survival rate of the first comer under double parasitism with a 25-h oviposition interval, although there was no difference between these triple and double parasitisms in terms of head width and developmental time. Under the conditions of other oviposition intervals, self-superparasitism produced null (1/1- and 24/24-h intervals) or negative fitness returns (24/1-h intervals). This suggests that self-superparasitism on hosts that were self-parasitised 1 h previously is profitable when conspecifics are present. 3.,When the female parasitoid laid an egg on a host harbouring the earlier comer(s) on the non-oviposition side, she often probed the non-oviposition side for infanticide, i.e. killing the first offspring. When the first and second comers were on different sides, the probing frequency at the third oviposition in triple parasitism with 1/24-h oviposition intervals was lower than that at the second oviposition in double parasitism with a 25-h oviposition interval. This difference was responsible for the above difference in survival rate between the triple and double parasitisms. [source] Failure of Helicobacter pylori Treatment After Regimes Containing Clarithromycin: New Practical Therapeutic OptionsHELICOBACTER, Issue 6 2008Bruno Sanches Abstract Failure of Helicobacter pylori treatment is a growing problem in daily practice. Aim:, To evaluate the efficacy of two new regimes as second-line options in a randomized and prospective study. Methods:, Patients in whom a first eradication regime containing clarithromycin had failed were included. After performing gastroscopy and a 13C-urea breath test (UBT), the patients were randomized to receive a combination of 20 mg of rabeprazole, 500 mg of levofloxacin, and 200 mg (two tablets) of furazolidone administered once daily for 10 days (RLF) or the combination of 20 mg of rabeprazole, 120 mg (two tablets) of bismuth subcitrate, 100 mg of doxycycline, and 200 mg of furazolidone, administered twice daily for 10 days (RBDF). Clinical examinations and new UBT were performed 60 days after therapy. Results:, Sixty patients were included (mean age, 46 years, 57% females). Two patients were excluded: one because of adverse effects and another as a result of protocol violation. Compliance was similar in both groups (90% took all medications correctly). Side-effects (96% mild) were observed in 87% of the patients and were comparable between groups, except diarrhea, which was more frequent in group RLF (p= .025). Intention-to-treat cure rates were 77% (95% confidence interval (CI): 62,93%) in the RLF group and 83% (95% CI: 68,97%) in the RBDF group (p= .750). Per-protocol cure rates were 80% (95% CI: 65,95%) in the RLF group and 82% (95% CI: 67,96%) in the RBDF group (p= 1.0). Conclusions:, Both once-daily triple (rabeprazole, levofloxacin, and furazolidone) and twice-daily quadruple therapy (rabeprazole, bismuth subcitrate, doxycycline, and furazolidone) for 10 days achieved encouraging results. Subsequent studies should be performed to evaluate antibiotic resistance, doses, dosing intervals, duration of treatment, and safety of these two regimes. [source] Single, twin and triple buried heating pipes: on potential savings in heat losses and costsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 14 2005Benny Bøhm Abstract In order to make district heating systems competitive in areas with single family houses or in other areas with low heat demands it is necessary to reduce the heat losses from the pipes. In recent years the twin pipe has become popular in the Nordic countries. In the article we describe how the heat loss and the heat loss coefficients can be calculated. We introduce the triple pipe with three media pipes (two supply pipes and one return pipe). The temperature dependency and the ageing of polyurethane insulation are briefly discussed. A comparison is made for different 80 mm distribution pipes and for different service pipes with respect to heat losses and to resources, i.e. materials needed for the casing and polyurethane insulation and the gravel in the excavations. For the distribution pipe we found that an egg-shaped twin pipe can reduce the heat loss by 37% and the investments by 12% compared with a pair of single pipes. For the service pipes we found that the triple pipe reduces the heat loss by 45% compared with a common pair of single pipes and by 24% compared with circular twin pipes. The reduction in investment index is 21%. The article also addresses the question of the heat exchange between the two media pipes in a twin pipe. Copyright © 2005 John Wiley & Sons, Ltd. [source] On open-set lattices and some of their applications in semanticsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 12 2003Mouw-Ching Tjiok In this article, we present the theory of Kripke semantics, along with the mathematical framework and applications of Kripke semantics. We take the Kripke-Sato approach to define the knowledge operator in relation to Hintikka's possible worlds model, which is an application of the semantics of intuitionistic logic and modal logic. The applications are interesting from the viewpoint of agent interactives and process interaction. We propose (i) an application of possible worlds semantics, which enables the evaluation of the truth value of a conditional sentence without explicitly defining the operator "," (implication), through clustering on the space of events (worlds) using the notion of neighborhood; and (ii) a semantical approach to treat discrete dynamic process using Kripke-Beth semantics. Starting from the topological approach, we define the measure-theoretical machinery, in particular, we adopt the methods developed in stochastic process,mainly the martingale,to our semantics; this involves some Boolean algebraic (BA) manipulations. The clustering on the space of events (worlds), using the notion of neighborhood, enables us to define an accessibility relation that is necessary for the evaluation of the conditional sentence. Our approach is by taking the neighborhood as an open set and looking at topological properties using metric space, in particular, the so-called ,-ball; then, we can perform the implication by computing Euclidean distance, whenever we introduce a certain enumerative scheme to transform the semantic objects into mathematical objects. Thus, this method provides an approach to quantify semantic notions. Combining with modal operators Ki operating on E set, it provides a more-computable way to recognize the "indistinguishability" in some applications, e.g., electronic catalogue. Because semantics used in this context is a local matter, we also propose the application of sheaf theory for passing local information to global information. By looking at Kripke interpretation as a function with values in an open-set lattice ,,U, which is formed by stepwise verification process, we obtain a topological space structure. Now, using the measure-theoretical approach by taking the Borel set and Borel function in defining measurable functions, this can be extended to treat the dynamical aspect of processes; from the stochastic process, considered as a family of random variables over a measure space (the probability space triple), we draw two strong parallels between Kripke semantics and stochastic process (mainly martingales): first, the strong affinity of Kripke-Beth path semantics and time path of the process; and second, the treatment of time as parametrization to the dynamic process using the technique of filtration, adapted process, and progressive process. The technique provides very effective manipulation of BA in the form of random variables and ,-subalgebra under the cover of measurable functions. This enables us to adopt the computational algorithms obtained for stochastic processes to path semantics. Besides, using the technique of measurable functions, we indeed obtain an intrinsic way to introduce the notion of time sequence. © 2003 Wiley Periodicals, Inc. [source] Quantum dynamics of a discontinuously kicked charged particle in harmonic, symmetric double, or triple wellsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 6 2009S. Ghosh Abstract The quantum dynamics of a charged particle in a harmonic trap in the presence of discontinuous reversals of a homogeneous or an inhomogeneous electric field is studied. The dynamics reveals classically expected patterns in harmonic wells. In a symmetric double-well potential, the discontinuously switched low intensity homogeneous electric field does not appear to assist tunneling, whereas an inhomogeneous electric field is found to assist the process. Resonance like enhancement is noticed at a critical reversal frequency. Dynamics in a triple well is also analyzed under similar conditions. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [source] Design and optimization of multi-band Wilkinson power dividerINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 1 2008Nihad Dib Abstract In this paper, a general and easy procedure for designing the symmetrical Wilkinson power divider that achieves equal-power split at N arbitrary frequencies is introduced. Each quarter-wave branch in the conventional Wilkinson divider is replaced by N sections of transmission lines, and the isolation between the output ports is achieved by using N resistors. The design parameters are the characteristic impedances and lengths of the N transmission line sections, and the N isolation resistors. The even,odd modes of analysis are used to derive the design equations. Closed-form expressions, which are suitable for CAD purposes, are derived for the dual-band divider. For N , 3, closed-form expressions are not available, and therefore, the powerful particle swarm optimization method is used to obtain the design parameters. Examples of the dual-, triple-, and quad-band dividers are presented to validate the proposed design procedure, and the results are compared, wherever possible, with published results using other methods. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. [source] RF MEMS impedance tuners for 6,24 GHz applicationsINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 3 2007Tauno Vähä-Heikkilä Abstract RF MEMS tuners with wide impedance coverage have been developed for 6,24 GHz noise parameter and load-pull measurement systems. The tuners are based on triple-, double-, and single-stub topologies loaded with switched MEMS capacitors. Several designs are presented, and they use 10,13 switched MEMS capacitors to produce 1024,8192 (210,213) different impedances. The measured impedance coverage agrees well with simulations and it is the widest ever measured impedance coverage from any planar tuner to-date. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007. [source] Prediction of triple-orbital diversity performance in Earth-space communicationINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 3 2002A. D. Panagopoulos Abstract Orbital diversity is considered to be an effective technique to overcome large fade margins in satellite communication links. This paper discusses triple-orbital diversity, which uses three satellites and an Earth receiving site. A method for calculating the outage probability of a triple-orbital diversity protection scheme is proposed. It is based on a model for convective raincells and the lognormal assumption for point rainfall rate statistics. Numerical results are compared with an available set of experimental data taken from a VSAT Earth-station located in Japan. The agreement was found to be quite encouraging. Some useful conclusions, concerning the relative advantage of using triple- against the double-orbital diversity scheme are also deduced. Copyright © 2002 John Wiley & Sons, Ltd. [source] Isothermal crystallization kinetics and melting behaviors of nanocomposites of poly(trimethylene terephthalate) filled with nano-CaCO3JOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007Mingtao Run Abstract The isothermal crystallization and subsequent melting behavior of poly(trimethylene terephthalate) (PTT) composites filled with nano-CaCO3 were investigated at designated temperatures with differential scanning calorimetry. The Avrami equation was used to fit the isothermal crystallization. The Avrami exponents were determined to be 2,3 for the neat PTT and PTT/CaCO3 composites. The particles of nano-CaCO3, acting as nucleating agents in the composites, accelerated the crystallization rate, with the half-time of crystallization decreasing or the growth rate constant (involving both nucleation and growth rate parameters) increasing. The crystallization activation energy calculated from the Arrhenius formula was reduced as the nano-CaCO3 content increased from 0 to 2%, and this suggested that nano-CaCO3 made the molecular chains of PTT easier to crystallize during the isothermal crystallization process. Subsequent melting scans of the isothermally crystallized composites exhibited triple or double melting endotherms: the greater the content was of nano-CaCO3, the lower the temperature was of the melting peak. The degree of crystallization deduced from the melt enthalpy of composites with the proper concentration of nano-CaCO3 was higher than that of pure PTT, but it was lower when the nano-CaCO3 concentration was more than 2%. The transmission electron microscopy pictures suggested that the dispersion state of nano-CaCO3 particles in the polymer matrix was even when its concentration was no more than 2%, whereas some agglomeration occurred when its concentration was 4%. Polarized microscopy pictures showed that much smaller or less perfect crystals formed in the composites because of the interaction between the molecular chains and nano-CaCO3 particles. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [source] Theoretical investigation of elastic flexural properties for multistranded orthodontic archwiresJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 3 2002Brian K. Rucker Abstract The bending and torsional stresses during flexure were detailed and simplified for a single twisted strand, which emulates a spring. General expressions were derived to evaluate the elastic properties (i.e., strength, stiffness, and range) of multistranded wires by combining the effects of a number of outer twisted strands, with or without an inner strand. Specific expressions were solved for single-stranded, twisted, and coaxial wires. Initially, we considered the following multistranded wire configurations: two- (twin), three- (triple), four-strand (quad) twisted, and coaxial wires. The elastic properties of the twin and quad wires were essentially subsets of the triple wire. For a given overall wire diameter (D) and helix angle (,), the ranges of multistranded wires were independent of wire configurations. By varying the , from 45 to 85°, the D from 0.394 to 0.546 mm (15.5 to 21.5 mil), and the stress at the proportional limit from 1.03 to 3.28 GPa (150 to 475 ksi), the theoretical elastic properties of triple and coaxial stainless steel wires matched many of the properties of conventional nickel titanium leveling wires. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 338,349, 2002 [source] A generalized higher order kernel energy approximation methodJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 16 2010Stewart N. Weiss Abstract We present a general mathematical model that can be used to improve almost all fragment-based methods for ab initio calculation of total molecular energy. Fragment-based methods of computing total molecular energy mathematically decompose a molecule into smaller fragments, quantum-mechanically compute the energies of single and multiple fragments, and then combine the computed fragment energies in some particular way to compute the total molecular energy. Because the kernel energy method (KEM) is a fragment-based method that has been used with much success on many biological molecules, our model is presented in the context of the KEM in particular. In this generalized model, the total energy is not based on sums of all possible double-, triple-, and quadruple-kernel interactions, but on the interactions of precisely those combinations of kernels that are connected in the mathematical graph that represents the fragmented molecule. This makes it possible to estimate total molecular energy with high accuracy and no superfluous computation and greatly extends the utility of the KEM and other fragment-based methods. We demonstrate the practicality and effectiveness of our model by presenting how it has been used on the yeast initiator tRNA molecule, ytRN (1YFG in the Protein Data Bank), with kernel computations using the Hartree-Fock equations with a limited basis of Gaussian STO-3G type. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010 [source] Systematic quantum chemical study of DNA-base tautomersJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 1 2004M. Piacenza Abstract The relative energies of the energetically low-lying tautomers of pyridone, cytosine, uracil, thymine, guanine, and iso-cytosine are studied by a variety of different quantum chemical methods. In particular, we employ density functional theory (DFT) using the six functionals HCTH407, PBE, BP86, B-LYP, B3-LYP, and BH-LYP, and the ab initio methods Hartree-Fock (HF), standard second-order Møller-Plesset perturbation theory (MP2), an improved version of it (SCS-MP2), and quadratic configuration interaction including single and double excitations (QCISD) and perturbative triple corrections [QCISD(T)]. A detailed basis set study is performed for the formamide/formamidic acid tautomeric pair. In general, large AO basis sets of at least valence triple-, quality including f-functions (TZV) are employed, which are found to be necessary for an accurate energetic description of the various structures. The performance of the more approximate methods is evaluated with QCISD(T)/TZV(2df,2dp) data taken as reference. In general it is found that DFT is not an appropriate method for the problem. For the tautomers of pyridone and cytosine, most density functionals, including the popular B3-LYP hybrid, predict a wrong energetic order, and only for guanine, the correct sequence of tautomers is obtained with all functionals. Out of the density functionals tested, BH-LYP, which includes a rather large fraction of HF exchange, performs best. A consistent description of the nonaromatic versus aromatic tautomers seems to be a general problem especially for pure, nonhybrid functionals. Tentatively, this could be assigned to the exchange potentials used while the functional itself, including the correlation part, seems to be appropriate. Out of the ab initio methods tested, the new SCS-MP2 approach seems to perform best because it effectively reduces some outliers obtained with standard MP2. It outperforms the much more costly QCISD method and seems to be a very good compromise between computational effort and accuracy. © 2003 Wiley Periodicals, Inc. J Comput Chem 1: 83,98, 2004 [source] Improved intermolecular force field for molecules containing H, C, N, and O atoms, with application to nucleoside and peptide crystalsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 11 2001Donald E. Williams Abstract A new intermolecular force field for nitrogen atoms in organic molecules was derived from a training dataset of 76 observed azahydrocarbon crystal structures and 11 observed heats of sublimation. The previously published W99 force field for hydrogen, carbon, and oxygen was thus extended to include nitrogen atoms. Nitrogen atoms were divided into four classes: N(1) for triply bonded nitrogen, N(2) for nitrogen with no bonded hydrogen (except the triple bonded case), N(3) for nitrogen with one bonded hydrogen, and N(4) for nitrogen with two or more bonded hydrogens. H(4) designated hydrogen bonded to nitrogen. Wavefunctions of 6-31g** quality were calculated for each molecule and the molecular electric potential (MEP) was modeled with net atomic and supplementary site charges. Lone pair electron charge sites were included for nitrogen atoms where appropriate, and methylene bisector charges were used for CH2 and CH3 groups when fitting the MEP. XH bond distances were set to standard values for the wave function calculation and then foreshortened by 0.1 Å for the MEP and force field fitting. Using the force field optimized to the training dataset, each azahydrocarbon crystal structure was relaxed by intermolecular energy minimization. Predicted maximum changes in unit cell edge lengths for each crystal were 3% or less. The complete force field for H, C, N, and O atoms was tested by intermolecular energy relaxation of nucleoside and peptide molecular crystals. Even though these molecules were not included in any of the training datasets for the force field, agreement with their observed crystal structures was very good, with predicted unit cell edge shifts usually less than 2%. These tests included crystal structures of representatives of all eight common nucleosides found in DNA and RNA, 15 dipeptides, four tripeptides, two tetrapeptides, and a pentapeptide with two molecules in the asymmetric unit. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1154,1166, 2001 [source] Benzdiynes revisited: ab initio and density functional theoryJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 9 2001Sundaram Arulmozhiraja Abstract Ab initio and density functional theory (DFT) studies were performed on three isomers of tetradehydrobenzene (benzdiynes). Four different density functionals (BPW91, BLYP, B3LYP, and B1LYP) and two higher levels of theory [QCISD and CCSD(T)] incorporating basis sets up to Dunning's correlation-consistent polarized valence triple-, (cc-pVTZ) were utilized for this purpose. Stability tests showed that more stable solutions were available for 1,4-benzdiyne with unrestricted than with restricted DFT, while solutions obtained with later descriptions of 1,3-benzdiyne and 1,2,3,5-tetradehydrobenzene were stable. UB3LYP provided better geometry for 1,4-benzdiyne. Unlike in an earlier study, the energy difference between 1,2,3,5-tetradehydrobenzene and 1,4-benzdiyne calculated with the B3LYP functional coincided well with that calculated at CCSD(T): 13.07 and 14.32 kcal/mol at the B3LYP/cc-pVTZ and CCSD(T)/cc-pVTZ levels, respectively. 1,2,3,5-Tetradehydrobenzene was 8 kcal/mol more stable than 1,3-benzdiyne at the CCSD(T)/cc-pVTZ level. The heats of formation of benzdiynes were obtained by using the G2, CBS-Q, and CBS-QB3 methodologies. The heats of formation calculated for 1,3-benzdiyne and 1,2,3,5-tetradehydrobenzene were 208.6 and 197.9 kcal/mol, respectively, at the CBS-QB3 level of theory. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 923,930, 2001 [source] Multiple primary malignancies in Spanish patients with hepatocellular carcinoma: Analysis of a hospital-based tumor registryJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8 2009Mario Fernández-Ruiz Abstract Background and Aim:, Little is known about the etiological associations and clinical features of extrahepatic primary malignant (EHPM) neoplasms in subjects with hepatocellular carcinoma (HCC). The aim of this study was to characterize this phenomenon in a consecutive series of Spanish patients in order to define its natural history and influence on survival. Methods:, A retrospective analysis of 245 patients with HCC during the period 1999,2003 was performed. Subjects identified with a second primary malignancy elsewhere constituted the EHPM group and were compared to patients with HCC alone. Results:, Eighteen patients (7.3%) had one or two associated extrahepatic malignancies (mean age 67.7 ± 9.7 years); of these, 17 had double cancer and one patient, triple. Nine of the 19 EHPM occurred before HCC diagnosis. The associated cancers included five cases of colorectal carcinoma, four cases of head and neck carcinoma, three cases of genitourinary cancer, two cases of lymphoproliferative disorder, one lung carcinoma, one skin melanoma, one breast carcinoma, and two cancers of unknown origin. Age and sex distribution, etiology of underlying hepatopathy, and liver function tests did not differ significantly between both groups. There was no difference between the overall survival rates. Conclusions:, EHPM is not rare among Spanish patients with HCC, although no specific clinicopathological features were detected in this population. Our results suggest that the association of another primary tumor with HCC does not imply a worse prognosis. The possibility of development of EHPM should be kept in mind when deciding on therapy and follow-up of HCC. [source] Primary adrenal insufficiency in childhood and adolescence: Advances in diagnosis and managementJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 11 2004PJ Simm Objectives: Primary adrenal insufficiency occurring in childhood and adolescence is due to abnormalities of gland development, gland responsiveness, and steroid biosynthesis or target organ response. Causes include autoimmune Addison's disease, tuberculosis, HIV, adrenoleukodystrophy, adrenal hypoplasia congenita and syndromes including triple A and IMAGe. We aimed to define the causes of adrenal insufficiency for a cohort of children in Melbourne. Methods: We reviewed the frequency and variety of presentation of primary adrenal insufficiency to the Royal Children's Hospital over the past 10 years through an audit of patient records, collating demographic information, presentation and investigations. Results: Sixteen cases (13 male, 3 female) of primary adrenal insufficiency were diagnosed at this hospital between January 1993 and July 2003. Median age at presentation was 7.7 years (range: birth to 14.8 years). Symptoms at presentation included weakness, increased pigmentation, abdominal pain, nausea, developmental delay or a reduction in school performance. Four patients presented with adrenal crisis. Median adrenocorticotrophic hormone (ACTH) at diagnosis was 246 pmol/L (range 30,969 pmol/L). Autoantibodies were positive in five patients. Five patients had elevation of very long chain fatty acids. Five patients were diagnosed with autoimmune adrenal insufficiency, five with adrenal hypoplasia congenita, five with adrenoleukodystrophy and one with IMAGe syndrome. Conclusions: A high index of suspicion results in earlier detection and possible prevention of adrenal crisis with a reduction in associated morbidities. Definitive diagnosis is now possible for almost all cases of primary adrenal insufficiency using technologies for screening autoimmunity, adrenoleukodystrophy (ALD) and genetic screening. [source] Antibody responses to Porphyromonas gingivalis infection in a murine abscess model , involvement of gingipains and responses to re-infectionJOURNAL OF PERIODONTAL RESEARCH, Issue 6 2003Masahiro Yoneda Background:,Porphyromonas gingivalis is one of the most important periodontopathogens. It produces cysteine proteinases named gingipains. We previously examined the effect of gingipains on abscess formation in a murine model. The rgpA rgpB double and kgp mutants induced smaller abscesses than the wild type. Moreover, the rgpA rgpB kgp triple (gingipain-null) mutant hardly showed lesion formation at all under the experimental conditions used, indicating that genes encoding gingipains are important for P. gingivalis virulence. Objectives:, Here, we further report the humoral immune responses induced by P. gingivalis strains. Methods:, After the lesions were apparently cured, sera were collected from the mice and immunoglobulin G (IgG) responses against the whole cell antigens of wild-type P. gingivalis were measured. Results:, Wild-type strain was found to induce a strong antibody reaction. On the other hand, the rgpA rgpB kgp triple and kgp mutants induced significantly lower antibody responses compared to the wild type. Western blotting analysis confirmed the differences in antibody production. Next, these mice were re-infected with wild-type strain. Mice that were first infected with wild-type strain showed significantly smaller lesion formation than control mice that were first infected with medium only. On the other hand, mice that were first infected with mutant strains devoid of gingipain activities did not show resistance to re-infection and immunoglobulins directed against gingipains may be protective. Conclusions:, These results suggest that gingipains play an important role in abscess formation in mice, and humoral immune responses seem to be partly responsible for the resistance to re-infection by P. gingivalis. [source] Clinical trial: clarithromycin vs. levofloxacin in first-line triple and sequential regimens for Helicobacter pylori eradicationALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2010J. MOLINA-INFANTE Aliment Pharmacol Ther,31, 1077,1084 Summary Background,Helicobacter pylori eradication rates with standard triple therapy have declined to unacceptable levels. Aim, To compare clarithromycin and levofloxacin in triple and sequential first-line regimens. Methods, A total of 460 patients were randomized into four 10-day therapeutic schemes (115 patients per group): (i) standard OCA, omeprazole, clarithromycin and amoxicillin; (ii) triple OLA, omeprazole, levofloxacin and amoxicillin; (iii) sequential OACM, omeprazole plus amoxicillin for 5 days, followed by omeprazole plus clarithromycin plus metronidazole for 5 days; and (iv) modified sequential OALM, using levofloxacin instead of clarithromycin. Eradication was confirmed by 13C-urea breath test. Adverse effects and compliance were assessed by a questionnaire. Results, Per protocol cure rates were: OCA (66%; 95% CI: 57,74%), OLA (82.6%; 75,89%), OACM (80.8%; 73,88%) and OALM (85.2%; 78,91%). Intention-to-treat cure rates were: OCA (64%; 55,73%), OLA (80.8%; 73,88%), OACM (76.5%; 69,85%) and OALM (82.5%; 75,89%). Eradication rates were lower with OCA than with all the other regimens (P < 0.05). No differences in compliance or adverse effects were demonstrated among treatments. Conclusions, Levofloxacin-based and sequential therapy are superior to standard triple scheme as first-line regimens in a setting with high clarithromycin resistance. However, all of these therapies still have a 20% failure rate. [source] 7-day rescue therapy with ranitidine bismuth citrate after Helicobacter pylori treatment failureALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2005J. P. Gisbert Summary Background :,Quadruple rescue therapy requires a complex scheme with four drugs. Aim :,To evaluate the efficacy of ranitidine bismuth citrate-tetracycline-metronidazole rescue regimen, and to compare two different metronidazole dose schemes. Methods :,Prospective multicentre study including proton-pump inhibitor + clarithromycin + amoxicillin failures. Rescue regimen included two 7-day treatment: (i) ranitidine bismuth citrate (400 mg b.d.)-tetracycline (500 mg q.d.s.)-metronidazole (500 mg t.d.s.; RTM1); or (ii) the same regimen but with metronidazole 250 mg q.d.s. (RTM2). Eradication was confirmed with 13C-urea breath test. Results :,A total of 150 patients were included (58 RTM1, 92 RTM2). All patients but two (one in each group) returned after treatment. About 86% in group RTM1 and 95% in RTM2 correctly took all the medications (P = 0.076). Per-protocol eradication rates with RTM1 and RTM2 were 74 (95% CI: 60,84) and 69% (59,78). The intention-to-treat eradication rates were 64 (51,75) and 70% (59,78; P > 0.05). The type of regimen was not associated with eradication in the multivariate analysis. Adverse effects were more frequent with RTM1 (41%) than with RTM2 (30%; P > 0.05). Conclusion :,Seven-day triple rescue therapy with ranitidine bismuth citrate-tetracycline-metronidazole is effective for Helicobacter pylori eradication, and represents an encouraging alternative to quadruple therapy, with the advantage of simplicity. The administration of metronidazole every 6 h (together with tetracycline), and at a low dose (250 mg), achieves similar efficacy and is probably associated with a better compliance and a lower incidence of adverse effects. [source] Furazolidone-based triple ,rescue therapy' vs. quadruple ,rescue therapy' for the eradication of Helicobacter pylori resistant to metronidazole,ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 7 2002V. Isakov Summary Background : The optimal treatment of patients with Helicobacter pylori resistant to metronidazole has not been established. Aim : To compare the efficacy of quadruple and furazolidone-based triple therapy in the eradication of H. pylori resistant to metronidazole. Methods : Duodenal ulcer patients (n = 70) in whom initial eradication therapy failed and who harboured H. pylori strains resistant to metronidazole were randomized to receive one of the following 7-day regimens: colloidal bismuth subcitrate, 240 mg, tetracycline, 750 mg, and furazolidone, 200 mg, each given twice daily (BTF), or omeprazole, 20 mg b.d., colloidal bismuth subcitrate, 240 mg b.d., tetracycline, 500 mg q.d.s., and metronidazole, 500 mg b.d. (OBTM). H.pylori status was assessed by culture, histology and rapid urease test before treatment and 4,6 weeks after therapy. Susceptibility to metronidazole was assessed by the agar dilution method. Results : H. pylori eradication rates with intention-to-treat/per protocol analyses were: BTF, 85.7%/90.9%; OBTM, 74.2%/89.6%. Duodenal ulcers were healed in nine of 10 (90%) patients in the BTF group and in all patients (12/12) (100%) in the OBTM group (P = N.S.). A significantly lower rate of adverse events was observed in the BTF group than in the OBTM group (31.4% vs. 60%, P = 0.03), but there was no difference in terms of discontinuation of treatment (2/35 vs. 6/35, P = N.S.). Conclusions : The 1-week BTF regimen was as effective as the OBTM regimen, and produced less adverse events. Thus, it may be used in patients in whom resistance of H. pylori to metronidazole is suspected. [source] Comparison of lansoprazole-based triple and dual therapy for treatment of Helicobacter pylori -related duodenal ulcer: an Asian multicentre double-blind randomized placebo controlled studyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 2 2000Wong Bakcground : In Asian countries with limited resources, clarithromycin-based triple therapy may not be readily available. There are also few direct comparisons of different regimens in Asia. Aim : To compare two lansoprazole-based non-clarithromycin triple therapies and one dual therapy in a prospective double-blind placebo-controlled study of Helicobacter pylori eradication and duodenal ulcer healing. Methods : Fourteen centres in Asia participated in this study. Patients with acute duodenal ulcer who were H. pylori -positive were recruited. They were randomized to receive: (a) lansoprazole 30 mg b.d., amoxycillin 1 g b.d. and metronidazole 500 mg b.d. for 2 weeks (LAM-2 W), or (b) LAM for 1 week and placebo (LAM-1 W), or (c) lansoprazole 30 mg b.d., amoxycillin 1 g b.d. and placebo for 2 weeks (LA-2 W). Upper endoscopy was repeated at week 6 to check for duodenal ulcer healing. Symptoms and side-effects were recorded. Results : A total of 228 patients were recruited, and two patients took less than 50% of the drugs. H. pylori eradication rates (intention-to-treat) were 68 out of 82 (83%) with LAM-2 W, 55 out of 71 (78%) with LAM-1 W and 43 out of 75 (57%) with LA-2 W. There were significant differences (P=0.001) in eradication rates when comparing either LAM-2 W or LAM-1 W with LA-2 W. The eradication rate in patients with metronidazole resistant H. pylori strains were significantly lower than those with metronidazole sensitive strains (P=0.0001). The duodenal ulcer healing rates at week 6 were 85%, 85% and 72% in LAM-2 W, LAM-1 W and LA-2 W, respectively (P=0.065). Side-effects occurred in 13%, 11% and 9% in LAM-2 W, LAM-1 W and LA-2 W, respectively. H. pylori eradication and initial ulcer size were factors affecting duodenal ulcer healing. Conclusions : This Asian multicentre study showed that 1-week lansoprazole-based triple therapy without clarithromycin has similar efficacy in H. pylori eradication and ulcer healing compared with a 2-week regimen. Both triple therapies were significantly better than dual therapy in H. pylori eradication. Therefore, 1-week lansoprazole-based triple therapy is as safe and effective as 2-week therapy in eradication of H. pylori infection and healing of duodenal ulcer in these Asian centres. [source] Compensatory thio,redox interactions between DsbA, CcdA and CcmG unveil the apocytochrome c holdase role of CcmG during cytochrome c maturationMOLECULAR MICROBIOLOGY, Issue 3 2008Serdar Turkarslan Summary During cytochrome c maturation (Ccm), the DsbA-dependent thio-oxidative protein-folding pathway is thought to introduce a disulphide bond into the haem-binding motif of apocytochromes c. This disulphide bond is believed to be reduced through a thio-reductive pathway involving the Ccm components CcdA (DsbD), CcmG and CcmH. Here, we show in Rhodobacter capsulatus that in the absence of DsbA cytochrome c levels were decreased and CcdA or CcmG or the putative glutathione transporter CydDC was not needed for Ccm. This decrease was not due to overproduction of the periplasmic protease DegP as a secondary effect of DsbA absence. In contrast, CcmH was absolutely necessary regardless of DsbA, indicating that compensatory thio,redox interactions excluded it. Remarkably, the double (DsbA,CcmG) and triple (DsbA,CcmG,CcdA) mutants produced cytochromes c at lower levels than the DsbA-null mutants, unless they contained a CcmG derivative (CcmG*) lacking its thio-reductive activity. Purified CcmG* can bind apocytochrome c in vitro, revealing for the first time a thiol-independent, direct interaction between apocytochrome c and CcmG. Furthermore, elimination of the thio,redox components does not abolish cytochrome c production, restricting the number of Ccm components essential for haem,apocyt c ligation per se during Ccm. [source] InAs/InP quantum dot photonic crystal microcavitiesPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2006Simon Frédérick Abstract We examine the optical mode structure of two-dimensional, photonic crystal microcavities based on triple missing hole defects in hexagonal symmetry, etched air-hole, suspended InP membranes. Polarisation dependent photoluminescence from InAs/InP quantum dots embedded within the cavities is used to explore mode energies and quality factors, Q, as a function of cavity design parameters. Optimised Q values are in excess of 7,500 for the modified y-dipole mode. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||||||||||||||||||||