Antitumor Activity of Artemisinin and Its Derivatives: From a Well-Known Antimalarial Agent to a Potential Anticancer Drug

Improvement of quality of life and survival of cancer patients will be greatly enhanced by the development of highly effective drugs to selectively kill malignant cells. Artemisinin and its analogs are naturally occurring antimalarials which have shown potent anticancer activity. In primary cancer cultures and cell lines, their antitumor actions were by inhibiting cancer proliferation, metastasis, and angiogenesis. In xenograft models, exposure to artemisinins substantially reduces tumor volume and progression. However, the rationale for the use of artemisinins in anticancer therapy must be addressed by a greater understanding of the underlying mechanisms involved in their cytotoxic effects. The primary targets for artemisinin and the chemical base for its preferential effects on heterologous tumor cells need yet to be elucidated. The aim of this paper is to provide an overview of the recent advances and new development of this class of drugs as potential anticancer agents

Circulation signature of vortical structures in turbulent boundary layers

The strength of vortical structures in a turbulent boundary layer is of interest in determining the generation and development of hairpin vortices. The dual-plane Particle Image Velocimetry (PIV) data at z+ = 110 (z/ = 0.09) and z/ = 0.53 (z+ = 575) in a turbulent boundary layer at Re = 1160 obtained by Ganapathisubramani et al. [7] were used to characterize the strength of the vortical structures by their circulation. The 3Dswirl was used to identify the vortex cores. The average number of swirl cores per field identified at z+ = 110 was approximately twice the average number at z/ = 0.53. The mean radius of the cores was found to decrease with increasing wall-normal distance. The main eigenvector of the velocity gradient tensor was used to determine the orientation of each vortex core. Circulation of the vortical structures was then calculated using the vorticity vector projected onto the main eigenvector direction. At z/ = 0.53, the mean circulation calculated using the eigenvector was almost the same as that using the full vorticity vector, but for z+ = 110 the mean circulation calculated using the eigenvector was 12% less than the mean circulation calculated using the vorticity vector

Los desafíos de la plurinacionalidad. Miradas críticas a 25 años del levantamiento indígena de 1990

En junio de 2015 la Universidad Politécnica Salesiana UPS a través de la Carrera de Gestión para el Desarrollo Local Sostenible conmemoró un Foro denominado “Los desafíos de la plurinacionalidad. Miradas críticas a 25 años del Levantamiento Indígena de 1990”. Este libro, con el mismo título de aquel evento, acota lo entonces discutido y reúne tres ensayos académicos escritos por Pablo Ortiz-T., Iván Narváez y Víctor Bretón Solo de Zaldívar, quienes a pesar de provenir de distintas trayectorias y campos, de una u otra manera confluyen y se complementan para poner a consideración tres grandes ejes y campos de debate y análisis: el paradigma y modelo de desarrollo vigente; el carácter del Estado y del sistema político y el marco jurídico relacionado al orden territorial. De una u otra manera, los autores abandonan elementos para proseguir la reflexión y discusión política - a propósito de la convocatoria que hiciera el movimiento indígena y su levantamiento en mayo-junio de 1990- en torno al derrotero a seguir como sociedad. Aún es un desafío a superar la impronta poscolonial, etnocéntrica y monocultural que marca al Estado y sus instituciones. Huella o herida que se resiste a desaparecer, colocando a la utopía de una sociedad intercultural y un Estado plurinacional que animó a miles de indígenas de todo el pais en 1990 a ocupar plazas, mercados, carreteras y templos como una tarea aún pendiente

Kalanchoe (Crassulaceae) as invasive aliens in China – new records, and actual and potential distribution

6 p., mapas. Post-print del artículo publicado en Journal of Biogeography. Versión revisada y corregida.Kalanchoe daigremontiana and K. delagoensis are reported for the first time from Sichuan and Hainan, China. For K. daigremontiana, a new population located in Chengdu downtown has been found, being the first one in western China and thus representing a significant range extension of this species within the country. For K. delagoensis, a new population has been observed in the Old Quarter of Haikou, being the southernmost population of this species in China. The distribution areas of both species in China are summarized based on a review of the literature, as well as that of their putative hybrid, K. × houghtonii. In addition, the potential range of K. delagoensis is estimated through a niche-based modelling approach. Finally, a key to taxa of Kalanchoe in China is provided.Z.-Q. Wang has benefited from China Postdoctoral Science Foundation funded project (2015M582547) and a postdoctoral fund of Sichuan University.Peer reviewe

Mechanical Reinforcement of Polymeric Fibers through Peptide Nanotube Incorporation

High aspect ratio nanotubular assemblies can be effective fillers in mechanically reinforced composite materials. However, most existing nanotubes used for structural purposes are limited in their range of mechanical, chemical, and biological properties. We demonstrate an alternative approach to mechanical reinforcement of polymeric systems by incorporating synthetic d,l-cyclic peptide nanotube bundles as a structural filler in electrospun poly d-, l-lactic acid fibers. The nanotube bundles self-assemble through dynamic hydrogen bonding from synthetic cyclic peptides to yield structures whose dimensions can be altered based on processing conditions, and can be up to hundreds of micrometers long and several hundred nanometers wide. With 8 wt % peptide loading, the composite fibers are >5-fold stiffer than fibers composed of the polymer alone, according to atomic force microscopy-based indentation experiments. This represents a new use for self-assembling cyclic peptides as a load-bearing component in biodegradable composite materials.Engineering and Applied Science

Deep learning for EEG-based Motor Imagery classification: Accuracy-cost trade-off

Electroencephalography (EEG) datasets are often small and high dimensional, owing to cumbersome recording processes. In these conditions, powerful machine learning techniques are essential to deal with the large amount of information and overcome the curse of dimensionality. Artificial Neural Networks (ANNs) have achieved promising performance in EEG-based Brain-Computer Interface (BCI) applications, but they involve computationally intensive training algorithms and hyperparameter optimization methods. Thus, an awareness of the quality-cost trade-off, although usually overlooked, is highly beneficial. In this paper, we apply a hyperparameter optimization procedure based on Genetic Algorithms to Convolutional Neural Networks (CNNs), Feed-Forward Neural Networks (FFNNs), and Recurrent Neural Networks (RNNs), all of them purposely shallow. We compare their relative quality and energy-time cost, but we also analyze the variability in the structural complexity of networks of the same type with similar accuracies. The experimental results show that the optimization procedure improves accuracy in all models, and that CNN models with only one hidden convolutional layer can equal or slightly outperform a 6-layer Deep Belief Network. FFNN and RNN were not able to reach the same quality, although the cost was significantly lower. The results also highlight the fact that size within the same type of network is not necessarily correlated with accuracy, as smaller models can and do match, or even surpass, bigger ones in performance. In this regard, overfitting is likely a contributing factor since deep learning approaches struggle with limited training examples

Active neutrino Oscillations and the SNO neutral Current measurement

We discuss the relation between the observed CC, ES, and NC fluxes with the flavor fractional content of the solar neutrino flux seen by SNO. By using existing estimates of the cross sections for the charged and neutral current reactions which take into account the detector resolution, we show how the forthcoming SNO rates unconstrained by the standard $^8$B shape could test the oscillations into active states. We perform a model independent analysis for the Super-K and SNO data, assuming a non distorted spectrum.Comment: 6pages, 4 figure

Stability of vortex lines in liquid 3He-4He mixtures at zero temperature

At low temperatures and 3He concentrations below 6.6 %, there is experimental evidence about the existence in liquid helium mixtures, of stable vortices with 3He-rich cores. When the system is either supersaturated or submitted to a tensile strength, vortices lose stability becoming metastable and eventually completely unstable, so that their cores freely expand. Within a density functional approach, we have determined the pressure-3He concentration curve along which this instability appears at zero temperature.Comment: Typeset using Revtex, 9 pages and 5 Postscript figure

FACTORES CONTEXTUALES IDENTIFICADOS EN LAS DECISIONES FINANCIERAS EN LA RELACIÓN DE PAREJA

The present study aimed to describe the contextual characteristics present in financial decisions (money management) in the couple relationship, 63 men and 50 women, between18 and 48 (M= 22.12; SD=5) years of age, from Queretaro, Mexico. They were selected through non-probability convenience sampling. To explore the contextual characteristics offinancial decisions in the couple, an open question was asked to obtain their descriptions. The analysis of results yielded categories named as affection, socioculture, economy andfinance, collaboration and gender equity, which demonstrate behaviors present in the couple, differentiated for men and women. The results describe a higher frequency indecisions based on socioculture and economic income as the main categories in the management of money in the couple. It is men who report these two categories with greaterrelevance, while women attach importance to collaboration in financial interaction within the relationship. Finally, the usefulness of the results related to socioculture and itsrelationship with money management within the couple´s dynamics is discussed, as well as its continuity for future research in financial psycholog

Hybridization between wild and cultivated potato species in the Peruvian Andes and biosafety implications for deployment of GM potatoes

The nature and extent of past and current hybridization between cultivated potato and wild relatives in nature is of interest to crop evolutionists, taxonomists, breeders and recently to molecular biologists because of the possibilities of inverse gene flow in the deployment of genetically-modified (GM) crops. This research proves that natural hybridization occurs in areas of potato diversity in the Andes, the possibilities for survival of these new hybrids, and shows a possible way forward in case of GM potatoes should prove advantageous in such areas