Tetrathiafulvalene-Calix[4]Pyrrole in the Chloride Anion Controled Molecular Recognition of 2,5,7-trinitro-9-dicyanomethylenefluorene-C60

Date du colloque : 05/2008International audienc

Blood Pressure And Cardiac Autonomic Modulation At Rest, During Exercise And Recovery Time In The Young Overweight

This study aimed to assess the blood pressure (BP), cardiac autonomic modulation at rest, in physical exercise and in the recovery in untrained eutrophic (E) and overweight (O) youth. The body mass index (BMI), waist circumference (WC), systolic BP-SBP (E: 109.80 ± 10.05; O: 121.85 ± 6.98 mmHg) and diastolic BP DBP (E: 65.90 ± 7.28; O: 73.14 ± 12.22 mmHg) were higher in overweight and the heart rate recovery (%HRR) was lower as compared with E volunteers. The BMI was associated with SBP (r= 0.54), DBP (r= 0.65), load on the heart rate variability threshold-HRVT (r=-0.46), %HRR2' (r=-0.48) and %HRR 5′ (r=-0.48), and WC was associated with SBP (r= 0.54), DBP (r= 0.64) and HRR2' (r=-0.49). The %HRR was associated to SBP, DBP and HRVT. In summary, the anthropometric variables, BP and cardiac autonomic modulation in the recovery are altered in overweight youth.221273

Preliminary Structural Analysis of the Western Curtain Wall of Elmina Castle, Elmina, Ghana

Elmina Castle, built in 1482 by the Portuguese, was the first of a series of European trading bases along the west coast of Africa and served as a commercial outpost for over four centuries of trade. The structure was captured by the Dutch in 1637 and became a major hub for the Atlantic Slave Trade. The castle is currently a UNESCO World Heritage Site and a Ghanaian national museum. The building is constructed from a combination of mud- and lime-mortared rough-hewed sandstone masonry. The primary focus of the analysis is the western curtain wall, which faces the only side of the castle accessible by land. A flaring at the base of the curtain wall points to the likely presence of an additional tower located approximately midway along the length of the wall in early Portuguese times. Using a pushover analysis with nonlinear 3D FE under Abaqus/CAE explicit formulation, we assess the stability of the tower-wall system to determine if a historical earthquake could have caused the tower to collapse. During the Dutch occupation, a two-story building, brick vaulted at the ground level, was added along the entire curtain wall. Using 2D plane strain nonlinear models, we evaluate the structural capacity of this vaulted system, considering its sensitivity to the density and the thickness of the loose material above the vault as well as the compressive strength of the rough-hewed sandstone masonry in the walls

Sex workers’ everyday security in the Netherlands and the impact of COVID-19

The COVID-19 pandemic has laid bare and exacerbates the existing insecurities of sex workers, a highly stigmatised, often criminalised and economically precarious group of workers. In the Netherlands, sex workers continue to experience different forms of violence despite the occupation’s legalisation, making it a ‘profession in limbo’. This paper therefore seeks to formulate answers to the questions: What are sex workers’ everyday experiences of (in)security? And: How has the COVID-19 pandemic influenced these? Given sex workers’ historical exclusion from policy formulation, we engage with these questions through collaborative research based on semi-structured interviews with sex workers in The Hague. Our analysis reveals a stark mismatch between the insecurities that sex workers’ experience and the concerns enshrined in the regulatory environment. While the municipality’s regulation of the sex industry focuses on sexually transmitted infections (STIs), occupational safety and health issues that sex workers experience also include psychological problems, insufficient hygiene in the workplace and the risk of violent clients. Besides, income insecurity is a key concern for sex workers. The decline in legal workspaces during the past two decades has not translated into higher service rates. Net earnings are further reduced when window operators pass on the risks of illness or damage to sex workers. Furthermore, operators act as powerful gatekeepers of access to remunerative employment. Here, sex workers identify gender-based discrimination with resulting more severe employment and income insecurities for transwomen and male sex workers. This legal liminality is enabled not only by the opaque legal status of sex work in the Netherlands, but also by the gendering of official regulation. Our study mirrors research from the Netherlands and beyond that documents sex workers’ widespread exclusion from COVID-19 support packages. Over and beyond this, we find that immigration status intersects with and mediates these exclusionary processes. We conclude that, firstly, to effectively address the insecurities that sex workers experience and fear, regulation needs to shift from its current criminal law and public health focus to a labour approach. Secondly, over and above such decriminalization, policies and civil society actors alike need to address the gender and sexual hierarchies that underpin sex worker stigma as well as migrants’ discrimination which have come out as powerful mediators of sex workers’ insecurities

Large atom number dual-species magneto-optical trap for fermionic 6Li and 40K atoms

We present the design, implementation and characterization of a dual-species magneto-optical trap (MOT) for fermionic 6Li and 40K atoms with large atom numbers. The MOT simultaneously contains 5.2x10^9 6Li-atoms and 8.0x10^9 40K-atoms, which are continuously loaded by a Zeeman slower for 6Li and a 2D-MOT for 40K. The atom sources induce capture rates of 1.2x10^9 6Li-atoms/s and 1.4x10^9 40K-atoms/s. Trap losses due to light-induced interspecies collisions of ~65% were observed and could be minimized to ~10% by using low magnetic field gradients and low light powers in the repumping light of both atomic species. The described system represents the starting point for the production of a large-atom number quantum degenerate Fermi-Fermi mixture

The Hahn Quantum Variational Calculus

We introduce the Hahn quantum variational calculus. Necessary and sufficient optimality conditions for the basic, isoperimetric, and Hahn quantum Lagrange problems, are studied. We also show the validity of Leitmann's direct method for the Hahn quantum variational calculus, and give explicit solutions to some concrete problems. To illustrate the results, we provide several examples and discuss a quantum version of the well known Ramsey model of economics.Comment: Submitted: 3/March/2010; 4th revision: 9/June/2010; accepted: 18/June/2010; for publication in Journal of Optimization Theory and Application

Considering discrepancy when calibrating a mechanistic electrophysiology model

Uncertainty quantification (UQ) is a vital step in using mathematical models and simulations to take decisions. The field of cardiac simulation has begun to explore and adopt UQ methods to characterize uncertainty in model inputs and how that propagates through to outputs or predictions; examples of this can be seen in the papers of this issue. In this review and perspective piece, we draw attention to an important and under-addressed source of uncertainty in our predictions—that of uncertainty in the model structure or the equations themselves. The difference between imperfect models and reality is termed model discrepancy, and we are often uncertain as to the size and consequences of this discrepancy. Here, we provide two examples of the consequences of discrepancy when calibrating models at the ion channel and action potential scales. Furthermore, we attempt to account for this discrepancy when calibrating and validating an ion channel model using different methods, based on modelling the discrepancy using Gaussian processes and autoregressive-moving-average models, then highlight the advantages and shortcomings of each approach. Finally, suggestions and lines of enquiry for future work are provided. This article is part of the theme issue ‘Uncertainty quantification in cardiac and cardiovascular modelling and simulation’

Variable Modified Chaplygin Gas in Anisotropic Universe with Kaluza-Klein Metric

In this work, we have consider Kaluza-Klein Cosmology for anisotropic universe where the universe is filled with variable modified chaplygin gas (VMCG). Here we find normal scalar field $\phi$ and the self interacting potential $V(\phi)$ to describe the VMCG Cosmology. Also we graphically analyzed the geometrical parameters named {\it statefinder parameters} in anisotropic Kaluza-Klein model. Next, we consider a Kaluza-Klein model of interacting VMCG with dark matter in the Einstein gravity framework. Here we construct the three dimensional autonomous dynamical system of equations for this interacting model with the assumption that the dark energy and the dark matter are interact between them and for that we also choose the interaction term. We convert that interaction terms to its dimensionless form and perform stability analysis and solve them numerically. We obtain a stable scaling solution of the equations in Kaluza-Klein model and graphically represent solutions.Comment: 11 pages, 13 figure

Chloride Anion Controlled Molecular “Switching”. Binding of 2,5,7-Trinitro-9-dicyanomethylenefluorene-C60 by Tetrathiafulvalene Calix[4]pyrrole and Photophysical Generation of Two Different Charge-Separated States

The binding of the snake-like trinitrodicyanomethylenefluorene-C60 derivative (TNDCF-C60) to the dynamic receptor, tetrathiafulvalene calix[4]pyrrole (TTF-calix[4]pyrrole), may be controlled via the use of a chloride anion as an external trigger. Whereas, in the absence of a chloride anion, the TNDCF ?tail? of the trinitrodicyanomethylenefluorene-C60 substrate binds to the TTF?calix[4]pyrrole in a 2:1 (substrate/receptor) stoichiometry in CH2Cl2 solution, addition of a chloride anion (yellow) leads the TNDCF tail to be displaced in favor of a bound C60 ?head?, a process that leads to the formation of a complex with overall 1:2:2 substrate/receptor/chloride anion stoichiometry. These chemical switching events are reflected in easy-to-visualize color changes, as well as in the production of two different kinds of charge-separated states following selective femtosecond photoexcitation