Characterization of a putative grapevine Zn transporter, VvZIP3, suggests its involvement in early reproductive development in Vitis vinifera L

Gonzalez, E (reprint author), Univ Talca, Inst Biol Vegetal & Biotecnol, Talca, Chile.Background: Zinc (Zn) deficiency is one of the most widespread mineral nutritional problems that affect normal development in plants. Because Zn cannot passively diffuse across cell membranes, it must be transported into intracellular compartments for all biological processes where Zn is required. Several members of the Zinc-regulated transporters, Iron-regulated transporter-like Protein (ZIP) gene family have been characterized in plants, and have shown to be involved in metal uptake and transport. This study describes the first putative Zn transporter in grapevine. Unravelling its function may explain an important symptom of Zn deficiency in grapevines, which is the production of clusters with fewer and usually smaller berries than normal. Results: We identified and characterized a putative Zn transporter from berries of Vitis vinifera L., named VvZIP3. Compared to other members of the ZIP family identified in the Vitis vinifera L. genome, VvZIP3 is mainly expressed in reproductive tissue - specifically in developing flowers - which correlates with the high Zn accumulation in these organs. Contrary to this, the low expression of VvZIP3 in parthenocarpic berries shows a relationship with the lower Zn accumulation in this tissue than in normal seeded berries where its expression is induced by Zn. The predicted protein sequence indicates strong similarity with several members of the ZIP family from Arabidopsis thaliana and other species. Moreover, VvZIP3 complemented the growth defect of a yeast Zn-uptake mutant, ZHY3, and is localized in the plasma membrane of plant cells, suggesting that VvZIP3 has the function of a Zn uptake transporter. Conclusions: Our results suggest that VvZIP3 encodes a putative plasma membrane Zn transporter protein member of the ZIP gene family that might play a role in Zn uptake and distribution during the early reproductive development in Vitis vinifera L., indicating that the availability of this micronutrient may be relevant for reproductive development

Modelado de un entorno e-Learning Adaptativo Inteligente analizando estados emocionales en estudiantes universitarios de Oaxaca

El presente documento muestra los resultados del desarrollo y aplicación de un ambiente e-Learning adaptativo inteligente a estudiantes universitarios del Istmo de Tehuantepec, Oaxaca. El objetivo es analizar como influyen actividades de aprendizaje individualizadas y estados emocionales en el desempeño académico. La identificación de los estados emocionales se llevó a cabo mediante algoritmos basados en Inteligencia Artificial. Los resultados mostraron una importante relación entre estado-emocional/calificación la cual hace referencia que la sorpresa y miedo generan tendencia a obtener buenas calificaciones, ya que se obtuvo un incremento en la media 6.8 a 9.7, estos resultados se compararon con los de semestres anteriores sin el uso de este ambiente de aprendizaje

Fighting the disagreement in Explainable Machine Learning with consensus

Machine learning (ML) models are often valued by the accuracy of their predictions. However, in some areas of science, the inner workings of models are as relevant as their accuracy. To understand how ML models work internally, the use of interpretability algorithms is the preferred option. Unfortunately, despite the diversity of algorithms available, they often disagree in explaining a model, leading to contradictory explanations. To cope with this issue, consensus functions can be applied once the models have been explained. Nevertheless, the problem is not completely solved because the final result will depend on the selected consensus function and other factors. In this paper, six consensus functions have been evaluated for the explanation of five ML models. The models were previously trained on four synthetic datasets whose internal rules were known in advance. The models were then explained with model-agnostic local and global interpretability algorithms. Finally, consensus was calculated with six different functions, including one developed by the authors. The results demonstrated that the proposed function is fairer than the others and provides more consistent and accurate explanations.Comment: 21 pages, 7 figure

Feeding Habits and Sexual Dimorphism of the Violet Goby, Gobioides broussoneti Lacepede (Pisces: Gobiidae), in the Estuarine System of Tecolutla, Veracruz, Mexico

Gobioides broussoneti were sampled in Silveña estuary, a branch of the Tecolutla estuary, Veracruz, Mexico, during 2 trips made between February 1998 and June 1999 to evaluate diet and sexual dimorphism. A total of 65 G. broussoneti ranging from 49–401 mm SL (0.7–124.2 g WW) were collected. There was a 1:1.2 sex ratio in favor of females. Seven food types were noted, with filamentous algae (25.4%) and detritus (21.3%) representing the principal food types. A 24 h feeding study revealed that this species feeds continuously throughout the day. The ovaries of all female G. broussoneti contained previtellogenic oocytes, characteristic of immature or regressed fish. In contrast, the lobular testis of the males contained late stages of spermatogenesis, suggesting that the fish examined were at the end of the reproductive season. Sexual dimorphism of G. broussoneti is distinguished by a small urogenital papilla, which is in the ventral region between the anal orifice and the anal fin origin. In the females it is short, blunt and has a yellow coloration; in males it is thin, pointed and has a smooth appearance. Only immature or regressed females were captured during this study indicating that G. broussoneti uses the Tecolutla estuary as a nursery and feeding ground. Questions about reproductive seasonality, ovarian development, and spawning of G. broussoneti need further investigation

WUW (What Users Want): A Service to Enhance Users' Satisfaction in Content-Based Peer-to-Peer Networks

20 pagesPeer-to-Peer (P2P) architectures are more and more used in Content Delivery Net- works (CDN), because the traditional client-server architectures are burdened by high distribution and maintenance cost, whereas in P2P systems those costs are almost negli- gible. In general, such applications do not take into account user preferences, other than QoS-related parameters. As users resources are the richness of P2P systems, we think it is important to satisfy their preferences concerning the usage of their resources. In this work we propose WUW (What Users Want), a service to improve users' satisfaction in a personal way. WUW runs on top of unstructured P2P systems, and its main goal is to allow users to strategically impact their local neighborhoods according to their own personal preferences. We present first results of experiments, deployed in a cluster, obtained with the prototype implementation of our service, which runs on top of Bit- Torrent, the most used file sharing protocol. We show that BitTorrent performances are not affected by the users strategic choices introduced by WUW. The advantage of our approach is that, without loosing performance, users can chose the peers they want to collaborate with according to their personal preferences

Heterologous production of human papillomavirus type-16 L1 protein by a lactic acid bacterium

<p>Abstract</p> <p>Background</p> <p>The expression of vaccine antigens in lactic acid bacteria (LAB) is a safe and cost-effective alternative to traditional expression systems. In this study, we investigated i) the expression of Human papillomavirus type 16 (HPV-16) L1 major capsid protein in the model LAB <it>Lactococcus lactis </it>and ii) the ability of the resulting recombinant strain to produce either capsomer-or virus-like particles (VLPs).</p> <p>Results and conclusion</p> <p>HPV-16 L1 gene was cloned into two vectors, pCYT and pSEC, designed for controlled intra- or extracellular heterologous expression in <it>L. lactis</it>, respectively. The capacity of <it>L. lactis </it>harboring either pCYT:L1 or pSEC:L1 plasmid to accumulate L1 in the cytoplasm and supernatant samples was confirmed by Western blot assays. Electron microscopy analysis suggests that, L1 protein produced by recombinant lactococci can self-assemble into structures morphologically similar to VLPs intracellularly. The presence of conformational epitopes on the <it>L. lactis</it>-derived VLPs was confirmed by ELISA using an anti-HPV16 L1 capsid antigen antibody. Our results support the feasibility of using recombinant food-grade LAB, such as <it>L. lactis</it>, for the production of L1-based VLPs and open the possibility for the development of a new safe mucosal vector for HPV-16 prophylactic vaccination.</p