A HOLISTIC REDUNDANCY- AND INCENTIVE-BASED FRAMEWORK TO IMPROVE CONTENT AVAILABILITY IN PEER-TO-PEER NETWORKS

Peer-to-Peer (P2P) technology has emerged as an important alternative to the traditional client-server communication paradigm to build large-scale distributed systems. P2P enables the creation, dissemination and access to information at low cost and without the need of dedicated coordinating entities. However, existing P2P systems fail to provide high-levels of content availability, which limit their applicability and adoption. This dissertation takes a holistic approach to device mechanisms to improve content availability in large-scale P2P systems. Content availability in P2P can be impacted by hardware failures and churn. Hardware failures, in the form of disk or node failures, render information inaccessible. Churn, an inherent property of P2P, is the collective effect of the users’ uncoordinated behavior, which occurs when a large percentage of nodes join and leave frequently. Such a behavior reduces content availability significantly. Mitigating the combined effect of hardware failures and churn on content availability in P2P requires new and innovative solutions that go beyond those applied in existing distributed systems. To addresses this challenge, the thesis proposes two complementary, low cost mechanisms, whereby nodes self-organize to overcome failures and improve content availability. The first mechanism is a low complexity and highly flexible hybrid redundancy scheme, referred to as Proactive Repair (PR). The second mechanism is an incentive-based scheme that promotes cooperation and enforces fair exchange of resources among peers. These mechanisms provide the basis for the development of distributed self-organizing algorithms to automate PR and, through incentives, maximize their effectiveness in realistic P2P environments. Our proposed solution is evaluated using a combination of analytical and experimental methods. The analytical models are developed to determine the availability and repair cost properties of PR. The results indicate that PR’s repair cost outperforms other redundancy schemes. The experimental analysis was carried out using simulation and the development of a testbed. The simulation results confirm that PR improves content availability in P2P. The proposed mechanisms are implemented and tested using a DHT-based P2P application environment. The experimental results indicate that the incentive-based mechanism can promote fair exchange of resources and limits the impact of uncooperative behaviors such as “free-riding”

Leukemia multiclass assessment and classification from Microarray and RNA-seq technologies integration at gene expression level

In more recent years, a significant increase in the number of available biological experiments has taken place due to the widespread use of massive sequencing data. Furthermore, the continuous developments in the machine learning and in the high performance computing areas, are allowing a faster and more efficient analysis and processing of this type of data. However, biological information about a certain disease is normally widespread due to the use of different sequencing technologies and different manufacturers, in different experiments along the years around the world. Thus, nowadays it is of paramount importance to attain a correct integration of biologically-related data in order to achieve genuine benefits from them. For this purpose, this work presents an integration of multiple Microarray and RNA-seq platforms, which has led to the design of a multiclass study by collecting samples from the main four types of leukemia, quantified at gene expression. Subsequently, in order to find a set of differentially expressed genes with the highest discernment capability among different types of leukemia, an innovative parameter referred to as coverage is presented here. This parameter allows assessing the number of different pathologies that a certain gen is able to discern. It has been evaluated together with other widely known parameters under assessment of an ANOVA statistical test which corroborated its filtering power when the identified genes are subjected to a machine learning process at multiclass level. The optimal tuning of gene extraction evaluated parameters by means of this statistical test led to the selection of 42 highly relevant expressed genes. By the use of minimum- Redundancy Maximum-Relevance (mRMR) feature selection algorithm, these genes were reordered and assessed under the operation of four different classification techniques. Outstanding results were achieved by taking exclusively the first ten genes of the ranking into consideration. Finally, specific literature was consulted on this last subset of genes, revealing the occurrence of practically all of them with biological processes related to leukemia. At sight of these results, this study underlines the relevance of considering a new parameter which facilitates the identification of highly valid expressed genes for simultaneously discerning multiple types of leukemia.This work was supported by Project TIN2015-71873-R (Spanish Ministry of Economy and Competitiveness -MINECO- and the European Regional Development Fund -ERDF) and Junta de Andalucı´a (P12–TIC–2082)

Genetic variability and structure of jaguar (Panthera onca) in Mexican zoos

ArtículoGenealogical records of animals (studbook) are created to avoid reproduction between closely related individuals, which could cause inbreeding, particularly for such endangered species as the Panthera onca (Linnaeus, 1758). Jaguar is the largest felid in the Americas and is considered an important ecological key species. In Mexico, wild jaguar populations have been significantly reduced in recent decades, and population decline typically accompany decreases in genetic variation. There is no current census of captive jaguars in Mexico, and zoos do not follow a standardized protocol in breeding programs based on genetic studies. Here, we emphasise the importance of maintaining an adequate level of genetic variation and propose the implementation of standardised studbooks for jaguars in Mexico, mainly to avoid inbreeding. In addition, achieving the aims of studbook registration would provide a population genetic characterisation that could serve as a basis for ex situ conservation programmes

Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

Estudios de Caso sobre Ciencias Agropecuarias y Rurales en el siglo XXI.

Libro científico sobre estudios de casos en el medio agropecuario y ruralCon el advenimiento del siglo XXI y el avance de los procesos de globalización, el medio rural presenta diversos cambios económicos, sociales, políticos y culturales. Lo anterior significa que el campo es un objeto de estudio altamente dinámico, complejo e inasible. las ciencias agropecuarias y rurales, en la actualidad, requieren de un abordaje sistémico e interdisciplinario que den cuenta de la heterogeneidad de situaciones y contextos que enfrenta el campo mexicano. La presente obra agrupa 18 estudios de caso, que capturan algunas fotografías de las diversas problemáticas de la ruralidad mexicana, con lo cual se pretende dar cuenta tanto de los objetivos de estudio como de la perspectiva teórico metodológico desde que estos son abordados. lo anterior tiene que ver con el hecho de que las ciencias agropecuarias y rurales manifiestan un alto grado de observación empírica, motivo por el que los estudios de caso se convierten en la perspectiva metodológica idónea que permite ir y venir de la realidad a la teoría y viceversa para la construcción de objetos de estudio. En este volumen se aborda una gran diversidad de casos, que sintetizan la heterogeneidad de enfoques y perspectivas mediante las cuales los fenómenos agropecuarios y rurales han sido abordados en el Instituto de Ciencias Agropecuarias y Rurales de la Universidad Autónoma del Estado de México, en los últimos 30 años

Hafnia paralvei ISOLATED FROM AN EMPHYSEMATOUS PYOMETRA IN A BITCH

We report the case of a 9-year-old female Labrador retriever, presented to the Veterinary Teaching Hospital with a history of bloody/purulent and malodourous vulvar discharge, decreased appetite and progressive abdominal enlargement for about 20 days. Clinical examination showed a distended and painful abdomen and tympanic sounds on percussion. The patient also presented systemic inflammatory response syndrome (SIRS) and a leukemoid reaction with leukocyte count of 77.9 x 109/L due to 62.32 x 109/L lymphocytes. The abdominal radiography showed distended tubular structures occupying most of the abdomen; dorsal displacement of the colon in the left-right lateral projection was also found. The ultrasonographic study also revealed tubular structures in the mid-abdomen that contained flowing fluid presenting mixed echogenicity and hyperechoic particles in suspension. The exploratory celiotomy showed that the uterine horns were distended and contained a mixture of gas and liquid, hence an ovariohysterectomy was performed. The uterine fluid was collected with aseptic technique into a syringe and submitted to the clinical pathology laboratory for aerobic and anaerobic culture and antibiotic sensitivity. Hafnia alvei (now classified as Hafnia paralvei ) was identified as the causative bacterial agent. Pyometra caused by gas-producing bacteria is a rare condition and is known as emphysematous pyometra. There are only six reports in the literature of this condition in bitches. A wide range of vaginal bacteria has been found in dogs with pyometra, but to our knowledge this is the first report of emphysematous pyometra caused by Hafnia paralvei in dogs

Characteristics of patients with heart failure and advanced chronic kidney disease (Stages 4–5) not undergoing renal replacement therapy (ERCA-IC Study)

Despite the frequent coexistence of heart failure (HF) in patients with advanced chronic kidney disease (CKD), it has been understudied, and little is known about its prevalence and prognostic relevance. A retrospective study of 217 patients with advanced CKD (stages 4 and 5) who did not undergo renal replacement therapy (RRT). The patients were followed up for two years. The primary outcome was all-cause death or the need for RRT. Forty percent of patients had a history of HF. The mean age was 78.2 ± 8.8 years and the mean eGFR was 18.4 ± 5.5 mL/min/1.73 m2. The presence of previous HF identified a subgroup of high-risk patients with a high prevalence of cardiovascular comorbidities and was significantly associated with the composite endpoint of all-cause hospitalization or need for RRT (66.7% vs. 53.1%, HR 95% CI 1.62 (1.04–2.52), p = 0.034). No differences were found in the need for RRT (27.6% vs. 32.2%, p = 0.46). Nineteen patients without HF at baseline developed HF during the follow-up and all-cause death was numerically higher (36.8 vs. 19.8%, p = 0.1). Patients with advanced CKD have a high prevalence of HF. The presence of previous HF identified a high-risk population with a worse prognosis that required close follow-up

Oralidad y proceso

El libro Oralidad y proceso presenta a la comunidad académica y a los profesionales del derecho reflexiones teóricas y prácticas acerca de la implementación de la oralidad en el proceso penal y laboral, asimismo las expectativas de su implementación en los procesos civil, de familia y contencioso administrativo. De antaño es la discusión alrededor la ineficacia del proceso, la mora judicial y la consecuente violación del derecho de acceso a la justicia y el debido proceso constitucional. En ese sentido se pregunta: ¿será acaso la oralidad el remedio a estos males? ¿la implementación de la oralidad será garantía de eficacia del proceso, ¿reducen los sistemas de procesamiento orales los índices de morosidad judicial Y en consecuencia, al potenciar la inmediación, la concentración, la contradicción y la publicidad\' se fortalece el derecho fundamental al debido proceso constitucional