Helical bias in supramolecular polymers accounts for different stabilities of kinetically trapped states

The idea to synthesize and self-assemble nano-graphenes with structural precision into supramolecular polymers is just one of Klaus Müllen's many pioneering contributions to the chemical sciences. To honor his impact in the field of polymer science, we here describe a study that combines experimental and computational methods in studying the stability of kinetically trapped states of supramolecular polymers. We show that the introduction of stereocenters in the sidechains allow helical supramolecular polymers based on chiral triphenylene-2,6,10-tricarboxamide monomers to escape a kinetic trap more efficiently than polymers based on their achiral analogs. Partial depolymerization of the kinetically trapped state by increasing the temperature followed by polymerization by lowering the temperature shows that monomers either polymerize on existing stacks or self-nucleate to form the thermodynamically more stable state. Chiral monomers prefer the latter more than achiral monomers.</p

Monotonicity of quantum ground state energies: Bosonic atoms and stars

The N-dependence of the non-relativistic bosonic ground state energy is studied for quantum N-body systems with either Coulomb or Newton interactions. The Coulomb systems are "bosonic atoms," with their nucleus fixed, and the Newton systems are "bosonic stars". In either case there exists some third order polynomial in N such that the ratio of the ground state energy to the respective polynomial grows monotonically in N. Some applications of these new monotonicity results are discussed

ππ\pi\pi Scattering in Three Flavour ChPT

We present the scattering lengths for the $\pi\pi$ processes in the three flavour Chiral Perturbation Theory (ChPT) framework at next-to-next-to-leading order. We then combine this calculation with the determination of the parameters from $K_{e4}$ and the masses and decay constants and compare with the results of a dispersive analysis of $\pi\pi$ scattering. The comparison indicates a small but nonzero value for the $1/N_c$ suppressed NLO low energy constants $L_4^r$ and $L_6^r$.Comment: 30 page

Estimation of a suitable Schmidt number range in diesel sprays at high injection pressure

The aim of this paper is to estimate a suitable range for the Schmidt number value in non-evaporative diesel sprays. For this purpose, mass distribution data obtained from X-ray absorption experiments existing in literature and a theoretical derivation for spray microscopic characteristics have been combined. Firstly, a procedure based on Gaussian concentration profiles has been proposed in order to interpret X-ray absorption results and relate them to physical parameters as local concentration or spray density. After this, information about FWHM (Full Width at Half Maximum) values has allowed to estimate spray angle in the tested conditions by the definition of Gaussian profiles for the mass radial distribution inside the spray. Following, a theoretical model dependent on momentum flux and Schmidt number has been used to simulate local mass concentration evolution along the spray axis and compare it with the values obtained from the experiments. The combination of the experimental and the theoretical data has allowed to estimate a suitable range for the Schmidt number value in such conditions as those existing in diesel sprays. © 2011 Elsevier Masson SAS. All rights reserved.This work was sponsored by "Vicerrectorado de Investigacion, Desarrollo e Innovacion" of the "Universitat Politecnica de Valencia" in the frame of the project "Estudio numeric de la cavitacion en toberas de inyeccion Diesel mediante Grid Computing (Cavigrid) Reference No 2597.Salvador Rubio, FJ.; Ruiz Rosales, S.; Gimeno, J.; De La Morena Borja, J. (2011). Estimation of a suitable Schmidt number range in diesel sprays at high injection pressure. International Journal of Thermal Sciences. 50(9):1790-1798. doi:10.1016/j.ijthermalsci.2011.03.030S1790179850

Liever inleiden dan afwachten bij aterme zwangerschapshypertensie en milde preeclampsie: HYPITAT-studie

OBJECTIVE: To investigate what would benefit women with mild full-term pregnancy-related hypertension most: induction of labour or expectant monitoring, from the perspective of clinical effectiveness, maternal quality of life, and costs. DESIGN: Randomised clinical trial. Trial registration number ISRCTN08132825. METHODS: We undertook a multicentre randomised controlled trial in 38 hospitals in the Netherlands between October 2005 and March 2008. We enrolled patients with a singleton pregnancy in cephalic presentation at 36-41 weeks' gestation, who had gestational hypertension or mild preeclampsia. Participants were randomly allocated to receive either induction of labour or expectant monitoring. The primary outcome was a composite measure of poor maternal outcome, defined as maternal mortality, maternal morbidity (eclampsia, 'haemolysis, elevated liver enzymes, low platelets' (HELLP) syndrome, pulmonary oedema, thrombo-embolic disease and abruptio placentae), progression to severe hypertension or proteinuria, and major postpartum haemorrhage. Secondary outcomes were mode of delivery, neonatal outcome, maternal quality of life and costs. Analysis was by intention to treat. RESULTS: A total of 756 patients were allocated to receive induction of labour (n = 377 patients) or expectant monitoring (n = 379). No cases of maternal or neonatal death or eclampsia were recorded. Development of poor maternal outcome was significantly lower in the induction of labour group (117 women) than the expectant monitoring group (166 women) (31% versus 44%; relative risk 0.71 (95% CI: 0.59-0.86); p < 0.001). The caesarean section rate was lower among women in the induction of labour group (n = 54) compared to women in the expectant monitoring group (n = 72) (14% versus 19%; relative risk 0.75 (95% CI: 0.55-1.04)< p = 0.085). Neonatal outcomes and quality of life were comparable between both groups. Induction of labour is a cost saving strategy (difference euro 831). CONCLUSION: For women with full-term gestational hypertension and pre-eclampsia, induction of labour is associated with improved maternal outcome and lower costs, without the additional risk of a caesarean section being necessary

Role of germline aberrations affecting CTNNA1, MAP3K6 and MYD88 in gastric cancer susceptibility

Background: In approximately 10% of all gastric cancer (GC) cases, a heritable cause is suspected. A subset of these cases have a causative germline CDH1 mutation; however, in most cases the cause remains unknown. Our objective was to assess to what extent these remaining cases may be explained by germline mutations in the novel candidate GC predisposing genes CTNNA1, MAP3K6 or MYD88. Methods: We sequenced a large cohort of unexplained young and/or familial patients with GC (n=286) without a CDH1germline mutation for germline variants affecting CTNNA1, MAP3K6 and MYD88 using a targeted next-generation sequencing approach based on single-molecule molecular inversion probes. Results: Predicted deleterious germline variants were not encountered in MYD88, but recurrently observed in CTNNA1 (n=2) and MAP3K6 (n=3) in our cohort of patients with GC. In contrast to deleterious variants in CTNNA1, deleterious variants in MAP3K6 also occur frequently in the general population. Conclusions: Based on our results MAP3K6 should no longer be considered a GC predisposition gene, whereas deleterious CTNNA1 variants are confirmed as an infrequent cause of GC susceptibility. Biallelic MYD88 germline mutations are at most a very rare cause of GC susceptibility as no additional cases were identified

Recurrent candidiasis and early-onset gastric cancer in a patient with a genetically defined partial MYD88 defect

Gastric cancer is caused by both genetic and environmental factors. A woman who suffered from recurrent candidiasis throughout her life developed diffuse-type gastric cancer at the age of 23 years. Using whole-exome sequencing we identified a germline homozygous missense variant in MYD88. Immunological assays on peripheral blood mononuclear cells revealed an impaired immune response upon stimulation with Candida albicans, characterized by a defective production of the cytokine interleukin-17. Our data suggest that a genetic defect in MYD88 results in an impaired immune response and may increase gastric cancer risk

Unraveling genetic predisposition to familial or early onset gastric cancer using germline whole-exome sequencing

Recognition of individuals with a genetic predisposition to gastric cancer (GC) enables preventive measures. However, the underlying cause of genetic susceptibility to gastric cancer remains largely unexplained. We performed germline whole-exome sequencing on leukocyte DNA of 54 patients from 53 families with genetically unexplained diffuse-type and intestinal-type GC to identify novel GC-predisposing candidate genes. As young age at diagnosis and familial clustering are hallmarks of genetic tumor susceptibility, we selected patients that were diagnosed below the age of 35, patients from families with two cases of GC at or below age 60 and patients from families with three GC cases at or below age 70. All included individuals were tested negative for germline CDH1 mutations before or during the study. Variants that were possibly deleterious according to in silico predictions were filtered using several independent approaches that were based on gene function and gene mutation burden in controls. Despite a rigorous search, no obvious candidate GC predisposition genes were identified. This negative result stresses the importance of future research studies in large, homogeneous cohorts

One-loop corrections to omega photoproduction near threshold

One-loop corrections to $\omega$ photoproduction near threshold have been investigated by using the approximation that all relevant transition amplitudes are calculated from the tree diagrams of effective Lagrangians. With the parameters constrained by the data of $\gamma N \to \pi N$, $\gamma N \to \rho N$, and $\pi N \to \omega N$ reactions, it is found that the one-loop effects due to the intermediate $\pi N$ and $\rho N$ states can significantly change the differential cross sections and spin observables. The results from this exploratory investigation suggest strongly that the coupled-channel effects should be taken into account in extracting reliable resonance parameters from the data of vector meson photoproduction in the resonance region.Comment: 19 pages, REVTeX, 14 figures, title changed, revised version to appear in Phys. Rev.