An emulation of VoD services using virtual network environments

Virtualization platforms are a viable alternative for the implementation of IP network experimentation environments. These platforms facilitate the conducting of tests as if a real environment were used and therefore can reduce the risk of failure as well as investment and experimentation costs. This paper proposes to develop a method to improve the results obtained in virtual network environments, trying to resemble those obtained in a real environment. To carry this out, we have emulated a video-on-demand service over ADSL using Xen as a virtualization tool, just as it would have been through a real ADSL connection. Connectivity, IP addressing, switching, routing and video streaming were tested to check the functionality of virtual network environments. Then, the bandwidth, the delay, and the inter-arrival time of video streaming packets were measured both in real and virtual environments. Finally, these parameters were tuned in the virtual network environments obtaining a similar behavior in clients and servers of both cases

Regulatory functions of NK cells during infections and cancer

After recognition, NK cells can kill susceptible target cells through perforin-dependent mechanisms or by inducing death receptor-mediated apoptosis, and they can also secrete cytokines that are pivotal for immunomodulation. Despite the critical role as effector cells against tumors and virus-infected cells, NK cells have been implicated in the regulation of T cell-mediated responses in different models of autoimmunity, transplantation, and viral infections. Here, we review the mechanisms described for NK cell-mediated inhibition of adaptive immune responses, with spotlight on the emerging evidence of their regulatory role that shapes antitumor immune responses.Fil: Zwirner, Norberto Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Domaica, Carolina Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Fuertes, Mercedes Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin

Leveraging NKG2D ligands in immuno-oncology

Immune checkpoint inhibitors (ICI) revolutionized the field of immuno-oncology and opened new avenues towards the development of novel assets to achieve durable immune control of cancer. Yet, the presence of tumor immune evasion mechanisms represents a challenge for the development of efficient treatment options. Therefore, combination therapies are taking the center of the stage in immuno-oncology. Such combination therapies should boost anti-tumor immune responses and/or target tumor immune escape mechanisms, especially those created by major players in the tumor microenvironment (TME) such as tumor-associated macrophages (TAM). Natural killer (NK) cells were recently positioned at the forefront of many immunotherapy strategies, and several new approaches are being designed to fully exploit NK cell antitumor potential. One of the most relevant NK cell-activating receptors is NKG2D, a receptor that recognizes 8 different NKG2D ligands (NKG2DL), including MICA and MICB. MICA and MICB are poorly expressed on normal cells but become upregulated on the surface of damaged, transformed or infected cells as a result of post-transcriptional or post-translational mechanisms and intracellular pathways. Their engagement of NKG2D triggers NK cell effector functions. Also, MICA/B are polymorphic and such polymorphism affects functional responses through regulation of their cell-surface expression, intracellular trafficking, shedding of soluble immunosuppressive isoforms, or the affinity of NKG2D interaction. Although immunotherapeutic approaches that target the NKG2D-NKG2DL axis are under investigation, several tumor immune escape mechanisms account for reduced cell surface expression of NKG2DL and contribute to tumor immune escape. Also, NKG2DL polymorphism determines functional NKG2D-dependent responses, thus representing an additional challenge for leveraging NKG2DL in immuno-oncology. In this review, we discuss strategies to boost MICA/B expression and/or inhibit their shedding and propose that combination strategies that target MICA/B with antibodies and strategies aimed at promoting their upregulation on tumor cells or at reprograming TAM into pro-inflammatory macrophages and remodeling of the TME, emerge as frontrunners in immuno-oncology because they may unleash the antitumor effector functions of NK cells and cytotoxic CD8 T cells (CTL). Pursuing several of these pipelines might lead to innovative modalities of immunotherapy for the treatment of a wide range of cancer patients.Fil: Fuertes, Mercedes Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Domaica, Carolina Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Zwirner, Norberto Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Química. Cátedra de Química Biológica; Argentin

Definición de un modelo genérico para la caracterización de escenarios virtuales de redes IP

Tesis doctoral inédita. Universidad Autónoma de Madrid, Escuela Politécnica Superior, junio de 201

A New Real-Time Flight Simulator for Military Training Using Mechatronics and Cyber-Physical System Methods

So far, the aeronautical industry has developed flight simulators and space disorientation with high costs. This chapter focuses on the design and implementation process of a low-cost real-time flight simulator for the training of armed force pilots using mathematical models of flight physics. To address such concern, the mathematical models of a Cessna type aircraft have been developed. This has been followed by a flight simulator, which operated with a new construction using a Stewart scale platform and operated by a joystick. Specifically, the simulator has been developed using an approximation of a physical cyber-system and a mechatronic design methodology that consists of mechanical, electrical and electronic elements that control the Stewart platform with three degrees of freedom. Based on software engineering, the algorithms of mathematical and physical models have been developed. These have been used to create an interactive flight simulator of an aircraft based on the Unity 3D game engine platform. The performance of the algorithms has been evaluated, using threads and processes to handle the communication and data transmission of the flight simulator to the Stewart platform. The evaluation of the developed simulator has been validated with professional pilots drilled with the Microsoft Flight Simulator. The results demonstrated that this flight simulator stimulates the development of skills and abilities for the maneuver and control of an aircraft

Implementación de un virus enfocado en dispositivos móviles Android. Un evento de hacking ético

Mobile devices have become part of daily social life. However, the vulnerabilities of this equipment are widespread, affecting information or damaging the system internally. Within this problem, this research proposes the implementation of a virus that allows affecting the Android victim device focusing on finding the vulnerabilities through penetration tests. The virus was designed through the principle of thread programming to a generation of scripts. Furthermore, the attack on Android devices’ vulnerable systems is conducted, applying social engineering techniques. Thus, through imperative programming techniques and functional, the access and use have been achieved, given that the virus had classes that allow connection and communication with the device. Each class was developed together so that in this way, there is a precise relationship between them. In this study, Kali Linux, with different Metasploit commands, was used.  The proofs of concept were conducted using controlled virtual network environments. For this, a server and a platform were used to use the IP and the Ngrok host, which allows us to generate       a link with the application that will violate Android’s services and security over secure tunnels. The results show that the operating system tends to be prone to internal damage. At the same time, users can be affected when their security and privacy are compromised. The proposal contributes significantly to a new version of Android’s security patches, implementing   a malware model that will integrate techniques to mitigate this problem in the future.Los dispositivos  móviles se  han convertido  en parte de la vida social diaria. Sin embargo, las vulnerabilidades de este equipo están muy extendidas, afectando la información o dañando el sistema internamente. Dentro de esta problemática, esta investigación propone la implementación de un virus que permita  afectar  al  dispositivo  Android  víctima  enfocándose en encontrar las vulnerabilidades mediante pruebas de penetración.   El   virus   fue   diseñado   a   través   del   principio   de programación de subprocesos para una generación de scripts. Además,  se  realiza  el  ataque  a  los  sistemas  vulnerables  de los  dispositivos  Android,  aplicando  técnicas  de  ingeniería  social.  Así,  mediante  técnicas  de  programación  imperativas  y funcionales, se ha logrado el acceso y uso, dado que el virus contaba  con  clases  que  permiten  la  conexión  y  comunicación con  el  dispositivo.  Cada  clase  se  desarrolló  en  conjunto  para que de esta manera, haya una relación precisa entre ellas. En este estudio se utilizó  Kali Linux, con diferentes comandos de Metasploit. Las pruebas de concepto se realizaron utilizando entornos  de  red  virtual  controlados.  Para  ello  se  utilizó  un servidor y una plataforma para utilizar la IP y el host Ngrok, lo  que  nos  permite  generar  un  enlace  con  la  aplicación  que vulnerara´ los servicios y la seguridad de Android sobre túneles seguros. Los resultados muestran que el sistema operativo tiende a ser propenso a sufrir daños internos. Al mismo tiempo, los usuarios pueden verse afectados cuando su seguridad y privacidad se ven comprometidas. La propuesta contribuye significativamente   a   una   nueva   versión   de   los   parches   de seguridad de Android, implementando un modelo de malware que integrara´ técnicas para mitigar este problema en el futuro

A container orchestration development that optimizes the etherpad collaborative editing tool through a novel management system

The use of collaborative tools has notably increased recently. It is common to see distinct users that need to work simultaneously on shared documents. In most cases, large companies provide tools whose implementations have been a very complicated and expensive task. Likewise, their platform deployment requirements should be robust hardware infrastructures. It becomes even more critical when their main target is to reach scalability and highavailability. Therefore, this study aims to design and implement a microservices-based collaborative architecture using assembled containers in the cloud, enabling them to deploy Etherpad instances to guarantee high availability. To ensure such a task, we developed and optimized a central management system that creates Etherpad instances and continuously interacts with other Etherpad tools running on Docker containers. This design goes from the monolithic Etherpad instantiation and handling towards a service architecture, where every Etherpad is offered as a microservice. Furthermore, the management system follows (implements) the Observer, Factory Method, Proxy, and Service Layerpopular design patterns. This allows users to gain more privacy through access to validations and shared resources. Our results indicate both the correct operation in the automation of containers’ creation for new users who register in the system and quantifiable improvement in performance.The funding of this research is provided by the Mobility Regulation of the Universidad de las Fuerzas Armadas ESPE, from Sangolquí, Ecuado

Sol-gel synthesis of cubic Nb/Ta-doped SrCoO3-δ with mixed nano-micro morphology

SrCo0.90M0.10O3-δ (M = Nb, Ta) perovskite powders were synthesized by sol-gel, using tartrate-precursor decomposition. The crystal structure of these materials was analyzed by x-ray powder diffraction. Rietveld refinements showed that both samples achieved the cubic crystal structure (Pm-3m), which was stabilized by the incorporation of highly-charged transition-metal cations at the octahedral sites. This synthesis method successfully lowered the calcination temperature relative to other methods mentioned in literature. The concentration of oxygen vacancies (δ value) was determined by thermogravimetric analysis. Microstructural analysis revealed micrometric scale particles with a superficial nanometric dendritic array with an average grain size less than 100 nm. The present work provides a new strategy to synthesize nanostructured perovskite materials that could have better electrical and electrochemical properties.Fil: Fuertes, Valeria Cintia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Eroles, Franco Matías. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Menzaque, Alejandro Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Peláez, Walter José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Lamas, Diego Germán. Universidad Nacional de San Martín; Argentin

Computer Graphics of the Regular Polygons and their Applications

Abstract. The computer graphics of regular polygons and their applications is a scarcely studied area that allows to create situations of significant learning by its mathematical and geometric content. This research presents the design and programming of regular polygons and composite sacred figures using computational analytical geometry and development tools such as C#, GDI+ graphics engine and Java with SWING graphical interface. In order to achieve this, the Agile Extreme Programming (XP) methodology has been used to translate computer graphics software applications, with the purpose of understanding how computer graphics work to generate combinations of geometric figures based on regular polygons, fully parameterizable. The proof of concept, which included the evaluation of the application performance in both the .NET framework and the NetBeans IDE were carried out with a student’s group of engineering in Computer Graphics subject

Los nevos melanocíticos premalignos quiescentes no expresan la molécula MHC class I chain-related protein A

The MHC class I chain-related protein A (MICA) is an inducible molecule almost not expressed by normal cells but strongly up-regulated in tumor cells. MICA-expressing cells are recognized by natural killer (NK) cells, CD8+ abTCR and gdTCR T lymphocytes through the NKG2D receptor. Engagement of NKG2D by MICA triggers IFN-g secretion and cytotoxicity against malignant cells. Although most solid tumors express MICA and this molecule is a target during immune surveillance against tumors, it has been observed that high grade tumors from different histotypes express low amounts of cell surface MICA due to a metalloprotease-induced shedding. Also, melanomas develop after a complex process of neotransformation of normal melanocytes. However, the expression of MICA in premalignant stages (primary human quiescent melanocytic nevi) remains unknown. Here, we assessed expression of MICA by flow cytometry using cell suspensions from 15 primary nevi isolated from 11 patients. When collected material was abundant, cell lysates were prepared and MICA expression was also analyzed by Western blot. We observed that MICA was undetectable in the 15 primary nevi (intradermic, junction, mixed, lentigo and congenital samples) as well as in normal skin, benign lesions (seborrheic keratosis), premalignant lesions (actinic keratosis) and benign basocellular cancer. Conversely, a primary recently diagnosed melanoma showed intense cell surface MICA. We conclude that the onset of MICA expression is a tightly regulated process that occurs after melanocytes trespass the stage of malignant transformation. Thus, analysis of MICA expression in tissue sections of skin samples may constitute a useful marker to differentiate between benign and malignant nevi.MHC class I chain-related protein A (MICA) es una molécula casi ausente en células normales pero sobre-expresada por células tumorales, que promueve el reconocimiento por células citotóxicas naturales (natural killer o NK) y por linfocitos T CD8+ aß y ?d a través del receptor NKG2D, lo que dispara la secreción de IFN-? y la citotoxicidad contra las células malignas. Aunque la mayoría de los tumores sólidos expresan MICA y esta molécula constituye un blanco durante la inmunovigilancia contra tumores, tumores de alto grado expresan bajos niveles de MICA en superficie celular debido al clivaje inducido por metaloproteasas. Asimismo, los melanomas se desarrollan luego de la neotransformación maligna de melanocitos. Sin embargo, se desconoce la expresión de MICA en estadios premalignos (nevos melanocíticos). En este trabajo analizamos la expresión de MICA en 19 nevos primarios de 11 pacientes mediante citometría de flujo. Cuando el material fue suficiente, también analizamos la expresión de MICA por Western blot. En ninguno de los 15 nevos primarios (intradérmicos, junction, mixtos, lentigo y congénitos) ni en muestras de piel normal, lesiones benignas (queratosis seborreica), premalignas (queratosis actínica) y cáncer benigno basocelular, detectamos expresión de MICA. Contrariamente, un melanoma primario de diagnóstico reciente mostró intensa expresión de MICA en superficie celular. Nuestros resultados indican que el inicio de la expresión de MICA ocurre una vez que la célula ha traspasado el estadio de transformación maligna, por lo que el análisis de su expresión en secciones de piel podría constituir un marcador útil para diferenciar nevos benignos de melanomas malignosFil: Fuertes, Mercedes Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Rossi, Lucas Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Peralta, Carlos Manuel. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Cabrera, Hugo Nestor. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Allevato, Miguel Angel. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Zwirner, Norberto Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentin