Resumen: Los frutales de carozo son afectados por diferentes plagas que pertenecen a diversos órdenes, siendo Grapholita molesta hacia la cual van dirigidas la mayoría de las intervenciones de ...control en estos cultivos. El manejo basado íntegramente en insecticidas ha demostrado que no siempre es efectivo. La necesidad de usar principios activos más específicos y de menor toxicidad para especies no blanco y benéficas plantea ser más conscientes de la biología de las plagas que queremos controlar, dado que tienen ventanas de aplicación muy estrechas para que estos sean efectivos. La posibilidad de controlar insectos utilizando su propia biología mediante el uso de feromonas abre las puertas a un nuevo tipo de control altamente específico a través de feromonas sexuales y de mínimo impacto ambiental. Estos compuestos pueden usarse bajo diferentes modalidades: monitoreo, confusión sexual, trampeo masivo o attract-and-kill. Cuando el manejo de poblaciones con feromonas se realiza en grandes extensiones la técnica expresa todo su potencial y sus beneficios son más estables y duraderos en el tiempo. En Uruguay este tipo de manejo se ha implementado formalmente desde el año 2012, con resultados por demás exitosos. El paso siguiente para una mejora en el monitoreo y el control sería la incorporación de kairomonas a esta ecuación, lo que aumentaría sustancialmente su eficiencia.
The presence of common symptoms, such as heartburn and regurgitation, usually make the diagnosis of gastroesophageal reflux disease (GERD) fairly straightforward. However, extraesophageal symptoms of ...GERD, such as asthma, noncardiac chest pain, and hoarseness, are often not recognized and therefore are poorly managed. This article sheds light on the atypical manifestations of GERD as well as current approaches to diagnosis and treatment.
Visceral hypersensitivity may play a role in the pathogenesis of functional chest pain, although the underlying mechanism(s) is unknown. We investigated the effects of theophylline, an adenosine ...receptor antagonist, on sensory perception and biomechanical properties of esophagus in patients with functional chest pain. Esophageal balloon distention was performed using impedance planimetry in 21 consecutive patients with functional chest pain. Patients found to have a hypersensitive esophagus received intravenous theophylline and balloon distension was repeated. If the hypersensitivity improved, oral theophylline was prescribed for three months as an open label trial. Balloon distension reproduced typical chest pain in 16 (76%) patients at thresholds suggestive of hypersensitivity. After theophylline infusion, pain thresholds increased in 12 (75%) patients. Median threshold pressures for discomfort and pain improved (P < 0.01). Cross-sectional area increased (P < 0.05) and the tension/strain association shifted to the right (P < 0.01). Seven of eight patients reported sustained improvement in pain after oral theophylline. Theophylline may ameliorate chest pain in patients with hypersensitive esophagus, possibly by altering adenosine-mediated nociception.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Spin polarization in chiral molecules is a magnetic molecular response associated with electron transport and enantioselective bond polarization that occurs even in the absence of an external ...magnetic field. An unexpected finding by Santos and co-workers reported enantiospecific NMR responses in solid-state cross-polarization (CP) experiments, suggesting a possible additional contribution to the indirect nuclear spin-spin coupling in chiral molecules induced by bond polarization in the presence of spin-orbit coupling. Herein we provide a theoretical treatment for this phenomenon, presenting an effective spin-Hamiltonian for helical molecules like DNA and density functional theory (DFT) results on amino acids that confirm the dependence of J-couplings on the choice of enantiomer. The connection between nuclear spin dynamics and chirality could offer insights for molecular sensing and quantum information sciences. These results establish NMR as a potential tool for chiral discrimination without external agents.
Dispersion interactions are one of the components of van der Waals (vdW) forces, which play a key role in the understanding of intermolecular interactions in many physical, chemical and biological ...processes. The theory of dispersion forces was developed by London in the early years of quantum mechanics. However, it was only in the 1960s that it was recognized that for molecules lacking an inversion center such as chiral and helical molecules, there are chirality-sensitive corrections to the dispersion forces proportional to the rotatory power known from the theory of circular dichroism and with the same distance scaling law R-6 as the London energy. The discovery of the Chirality-Induced Spin Selectivity (CISS) effect in recent years has led to an additional twist in the study of chiral molecular systems, showing a close relation between spin and molecular geometry. Motivated by it, we propose in this investigation to describe the mutual induction of charge and spin-density fluctuations in a pair A-B of chiral molecules by a simple physical model. The model assumes that the same fluctuating electric fields responsible for vdW forces can induce a magnetic response via a Rashba-like term, so that an spin-orbit field acting on molecule B is generated by the electric field arising from charge density fluctuations in molecule A (and viceversa). Within a second-order perturbative approach, these contributions manifest as an effective intermolecular exchange interaction. Although expected to be weaker than the standard London forces, these interactions display the same R\(^6\) distance scaling.
The effect of the intramolecular coupling, on the refractive index, up to third order in the external field amplitude, is studied for a dilute aqueous solution in which the solute molecules are ...described by a simple model consisting of two coupled harmonic electronic potentials displaced in both equilibrium distance and energy. The effect of the intramolecular coupling on the refractive index appears to be sizeable, particularly in the weak- and intermediate-coupling region.
Evolving biosciences in multi-agent systems Mujica-V, V.E.; Sisalem, D.; Popescu-Zeletin, R.
IEEE/WIC/ACM International Conference on Intelligent Agent Technology,
2005
Conference Proceeding
This paper proposes a strong research interest in a field related to bioinformatics and computational biology in a multi-agent system (MAS). We promote the use of evolutionary computation within ...intelligent multi-agent systems taking particularly the enhancement of the neuron routing algorithm (NEURAL) in mobile ad hoc network (MANET). More precisely, we develop an intelligent mobile agent called the neural agent which significantly improves the performance of neural. Results demonstrated that the neural agent leads to significant benefits in the average end-to-end delay and the packet delivery ratio of the routing protocol.
