Structural Requirements for the Antiprotozoal Activity of 4-Aminobicyclo[2.2.2]octan-2-ols

Several 4-aminobicyclo[2.2.2]octan-2-ones and -ols were synthesized using different pathways. The new compounds were investigated for their activity against Trypanosoma b. rhodesiense, the causative organism of East African sleeping sickness and Plasmodium falciparum the protozoan parasite which causes Malaria tropica. The results are compared to the activities of known compounds and the influence of the substitution of the bicyclo[2.2.2]octane skeleton on the biological activities is discussed.     

Segregation of organic impurities in thin electroplated Cu metallizations

This article presents investigations regarding the incorporation of organic impurities in thin electroplated Cu metallizations. RF-GD-OES (radio frequency glow discharge optical emission spectrometry) was used for detection of C and H as indicators for incorporated hydrocarbon molecules. The presented results indicate a fragmentation of incorporated hydrocarbons and their constrict segregation near the Cu surface. The bilateral relationship between incorporated organic impurities and intrinsic stress behavior is associated with the Gorky effect.     

Moving inelastic discontinuities and applications to martensitic phase transition

Summary In this work, equations of the kinetics and kinematics are developed for heterogeneous materials containing inelastic discontinuities with moving boundaries. From the derived free energy and the power of external forces one obtains the driving force acting on the moving boundary. Introducing the interface operators and some hypothesis on inelastic fields, one gets the driving force for the formation of an ellipsoidal domain. The theoretical model is illustrated by the derivation of nucleation and growth conditions of a martensitic plate inside an inhomogeneous plastic strain field. The obtained results are combined with a study of the kinetics and kinematics to derive the constitutive equation of an austenitic single crystal, from which the overall behavior of polycrystalline TRIP steels is deduced using the self-consistent scale-transition method. Comparison with experimental data shows a good agreement. Received 7 May 1999; accepted for publication 14 June 1999     

Detecting inefficiently managed categories in a retail store

Growth in operational complexity is a worldwide reality in the retail industry. One of the most tangible expressions of this phenomenon is the vast increase in the number of products offered. To cope with this problem, the industry has developed the ‘category management’ approach, in which groups of products with certain common characteristics are grouped together into ‘categories’, managed as if they were independent business units. In this paper, we propose a model to evaluate relative category performance in a retail store, considering they might have different business objectives. Our approach is based on Data Envelopment Analysis techniques and requires a careful definition of the resources that categories use to contribute to achieving their business objectives. We illustrate how to use our approach by applying it to the evaluation of several categories in a South American supermarket. The empirical results show that, even for very conservative assumptions, the model has a significant discriminatory power, identifying 25% of the sample as not operating efficiently. Although efficiency scores might exhibit a relatively large dispersion, the set of efficient units is robust to data variations.     

Controlling the Shape of Evaporating Droplets by Ionic Strength: Formation of Highly Anisometric Silica Supraparticles

Anisometric silica supraparticles are produced by a simple process of evaporation of sessile droplets containing fumed silica deposited on a superhydrophobic substrate. The shape of the supraparticles is directly controlled by the salt (NaCl) concentration, becoming anisometric beyond a threshold concentration, as quantified by light microscopy. This process is easily extended to supraparticles containing further functional colloidal components.     

Resurgent Transseries and the Holomorphic Anomaly: Nonperturbative Closed Strings in Local $${\mathbb{C}\mathbb{P}^2}$$

The holomorphic anomaly equations describe B-model closed topological strings in Calabi–Yau geometries. Having been used to construct perturbative expansions, it was recently shown that they can also be extended past perturbation theory by making use of resurgent transseries. These yield formal nonperturbative solutions, showing integrability of the holomorphic anomaly equations at the nonperturbative level. This paper takes such constructions one step further by working out in great detail the specific example of topological strings in the mirror of the local \({\mathbb{C}\mathbb{P}^2}\) toric Calabi–Yau background, and by addressing the associated (resurgent) large-order analysis of both perturbative and multi-instanton sectors. In particular, analyzing the asymptotic growth of the perturbative free energies, one finds contributions from three different instanton actions related by \({\mathbb{Z}_3}\) symmetry, alongside another action related to the Kähler parameter. Resurgent transseries methods then compute, from the extended holomorphic anomaly equations, higher instanton sectors and it is shown that these precisely control the asymptotic behavior of the perturbative free energies, as dictated by resurgence. The asymptotic large-order growth of the one-instanton sector unveils the presence of resonance, i.e., each instanton action is necessarily joined by its symmetric contribution. The structure of different resurgence relations is extensively checked at the numerical level, both in the holomorphic limit and in the general nonholomorphic case, always showing excellent agreement with transseries data computed out of the nonperturbative holomorphic anomaly equations. The resurgence relations further imply that the string free energy displays an intricate multi-branched Borel structure, and that resonance must be properly taken into account in order to describe the full transseries solution.     

Synthesis and Antimicrobial Activity of New Derivatives of 1,3,4‐Thiadiazoles and 1,2,4‐Triazoles with 5‐Nitroindazole as Support

The synthesis of new derivatives of 1,3,4‐thiadiazoles and 1,2,4‐triazoles was achieved using the 1,4‐disubstituted thiosemicarbazides as intermediaries.