Search results for "H.P.M."
showing 10 items of 738 documents
Search compounds with antimicrobial activity by applying molecular topology to selected quinolones.
2003
Molecular topology was used to obtain substances with antimicrobial activity. Selected quinolones were employed to develop the corresponding connectivity functions and discriminant equation. Limiting functions were selected that allowed the discriminant function to more efficiently distinguish substances with and without antibacterial activity. Antibacterial tests were run to confirm the theoretically established activity.
Ciudadanía y transformación social: Nuevos discursos y acción contra el cambio climático
2021
El canvi climatic protagonitza el debat mediambiental des de fa tres decades. Malgrat els acords internacionals adoptats, la humanitat no ha aconseguit frenar l’augment de la temperatura planetaria. La crisi del coronavirus ha relegat el debat sobre l’emergencia climatica a un segon pla, encara que les connexions entre canvi climatic i pandemia demostren les multiples raons que tenim per a actuar pel clima. Les politiques publiques han afavorit regulacions, instruments de mercat i estrategies de modernitzacio ecologica que consoliden un capitalisme verd que agreuja el problema i el despolititza. La lluita contra el canvi climatic necessita un nou enfocament, basat en la politica ciutadana i…
La constitution des classes dans les écoles. Contraintes de contexte ou stratégies d'acteurs ?: Rapport intermédiaire pour le PIREF
2005
05004; Analyse des pratiques de constitution des classes (nombre et nature des classes au sein des écoles), puis des modalités d'affectation des élèves et des enseignants dans ces classes et enfin de l'efficacité pédagogique des différents types de groupement réalisés.
Correlation between mutation rate and genome size in riboviruses: mutation rate of bacteriophage Qβ.
2013
Abstract Genome sizes and mutation rates covary across all domains of life. In unicellular organisms and DNA viruses, they show an inverse relationship known as Drake’s rule. However, it is still unclear whether a similar relationship exists between genome sizes and mutation rates in RNA genomes. Coronaviruses, the RNA viruses with the largest genomes (∼30 kb), encode a proofreading 3′ exonuclease that allows them to increase replication fidelity. However, it is unknown whether, conversely, the RNA viruses with the smallest genomes tend to show particularly high mutation rates. To test this, we measured the mutation rate of bacteriophage Qβ, a 4.2-kb levivirus. Amber reversion-based Luria–D…
Variability in the mutation rates of RNA viruses
2014
ABSTRACT: It is well established that RNA viruses show extremely high mutation rates, but less attention has been paid to the fact that their mutation rates also vary strongly, from 10-6 to 10-4 substitutions per nucleotide per cell infection. The causes explaining this variability are still poorly understood, but candidate factors are the viral genome size and polarity, host-specific gene expression patterns, or the intracellular environment. Differences between animal and plant viruses, or between arthropod-borne and directly transmitted viruses have also been postulated. Finally, RNA viruses may be able to regulate the rate at which new mutations spread in the population by modifying f…
Variation in RNA virus mutation rates across host cells.
2014
It is well established that RNA viruses exhibit higher rates of spontaneous mutation than DNA viruses and microorganisms. However, their mutation rates vary amply, from 10−6 to 10−4 substitutions per nucleotide per round of copying (s/n/r) and the causes of this variability remain poorly understood. In addition to differences in intrinsic fidelity or error correction capability, viral mutation rates may be dependent on host factors. Here, we assessed the effect of the cellular environment on the rate of spontaneous mutation of the vesicular stomatitis virus (VSV), which has a broad host range and cell tropism. Luria-Delbrück fluctuation tests and sequencing showed that VSV mutated similarly…
Antiproliferative Effects of St. John’s Wort, Its Derivatives, and Other Hypericum Species in Hematologic Malignancies
2021
Hypericumis a widely present plant, and extracts of its leaves, flowers, and aerial elements have been employed for many years as therapeutic cures for depression, skin wounds, and respiratory and inflammatory disorders. Hypericum also displays an ample variety of other biological actions, such as hypotensive, analgesic, anti-infective, anti-oxidant, and spasmolytic abilities. However, recent investigations highlighted that this species could be advantageous for the cure of other pathological situations, such as trigeminal neuralgia, as well as in the treatment of cancer. This review focuses on the in vitro and in vivo antitumor effects of St. John’s Wort (Hypericum perforatum), its derivat…
Surrogate Data Analysis for Assessing the Significance of the Coherence Function
2004
In cardiovascular variability analysis, the significance of the coupling between two time series is commonly assessed by setting a threshold level in the coherence function. While traditionally used statistical tests consider only the parameters of the adopted estimator, the required zero-coherence level may be affected by some features of the observed series. In this study, three procedures, based on the generation of surrogate series sharing given properties with the original but being structurally uncoupled, were considered: independent identically distributed (IID), Fourier transform (FT), and autoregressive (AR). IID surrogates maintained the distribution of the original series, while …
How to Sell SaaS: A Model for Main Factors of Marketing and Selling Software-as-a-Service
2011
Software-as-a-Service providers have been growing fast while the contemporary research literature has neglected analysis of their business-critical marketing and sales processes. In this paper we collect the key factors characterizing how to market and sell SaaS to business customers into an eight dimensional model. We also use an explorative multi-case study to observe six SaaS providers and validate the model. The interviewed providers emphasized use of the Internet for marketing communication while personal direct sale was the dominating sales approach. Customer acquisition cost was the key performance indicator for marketing and sales while customer lifetime value and churn were the KPI…
Portfolio: Integrating Writing, Learning and Assessment
2001
This chapter examines portfolio assessment as a tool to support learning by integrating writing in various learning tasks and environments. The author argues that the constructivist and socioconstructivist views of learning necessitate new ideas also in the assessment where the learners have the main role and where the partnership between students and teachers has to be renegotiated. In particular, renegotiation is needed in making decisions on assessment criteria for writing and learning that respect learners’ individuality and diversity and empower students with regard to their learning. The learning, assessment and negotiation can take place in various ways and environments. Accordingly,…