New bounds for truthful scheduling on two unrelated selfish machines

We consider the minimum makespan problem for $n$ tasks and two unrelated parallel selfish machines. Let $R_n$ be the best approximation ratio of randomized monotone scale-free algorithms. This class contains the most efficient algorithms known for truthful scheduling on two machines. We propose a new $Min-Max$ formulation for $R_n$, as well as upper and lower bounds on $R_n$ based on this formulation. For the lower bound, we exploit pointwise approximations of cumulative distribution functions (CDFs). For the upper bound, we construct randomized algorithms using distributions with piecewise rational CDFs. Our method improves upon the existing bounds on $R_n$ for small $n$. In particular, we obtain almost tight bounds for $n=2$ showing that $|R_2-1.505996|<10^{-6}$.Comment: 28 pages, 3 tables, 1 figure. Theory Comput Syst (2019

Vanguardias silenciadas: tejidos de la memoria

Antología de textos y lecturas de mujeres

Positive semidefinite approximations to the cone of copositive kernels

It has been shown that the maximum stable set problem in some infinite graphs, and the kissing number problem in particular, reduces to a minimization problem over the cone of copositive kernels. Optimizing over this infinite dimensional cone is not tractable, and approximations of this cone have been hardly considered in literature. We propose two convergent hierarchies of subsets of copositive kernels, in terms of non-negative and positive definite kernels. We use these hierarchies and representation theorems for invariant positive definite kernels on the sphere to construct new SDP-based bounds on the kissing number. This results in fast-to-compute upper bounds on the kissing number that lie between the currently existing LP and SDP bounds.Comment: 29 pages, 2 tables, 1 figur

Salivary Biomarkers for Oral Squamous Cell Carcinoma Diagnosis and Follow-Up: Current Status and Perspectives

Oral cancer is the sixth most common cancer type in the world, and 90% of it is represented by oral squamous cell carcinoma (OSCC). Despite progress in preventive and therapeutic strategies, delay in OSCC diagnosis remains one of the major causes of high morbidity and mortality; indeed the majority of OSCC has been lately identified in the advanced clinical stage (i.e., III or IV). Moreover, after primary treatment, recurrences and/or metastases are found in more than half of the patients (80% of cases within the first 2 years) and the 5-year survival rate is still lower than 50%, resulting in a serious issue for public health. Currently, histological investigation represents the “gold standard” of OSCC diagnosis; however, recent studies have evaluated the potential use of non-invasive methods, such as “liquid biopsy,” for the detection of diagnostic and prognostic biomarkers in body fluids of oral cancer patients. Saliva is a biofluid containing factors such as cytokines, DNA and RNA molecules, circulating and tissue- derived cells, and extracellular vesicles (EVs) that may be used as biomarkers; their analysis may give us useful information to do early diagnosis of OSCC and improve the prognosis. Therefore, the aim of this review is reporting the most recent data on saliva biomarker detection in saliva liquid biopsy from oral cancer patients, with particular attention to circulating tumor DNA (ctDNA), EVs, and microRNAs (miRNAs). Our results highlight that saliva liquid biopsy has several promising clinical uses in OSCC management; it is painless, accessible, and low cost and represents a very helpful source of diagnostic and prognostic biomarker detection. Even if standardized protocols for isolation, characterization, and evaluation are needed, recent data suggest that saliva may be successfully included in future clinical diagnostic processes, with a considerable impact on early treatment strategies and a favorable outcome

Sochi in 1930s: official ideology and implementation realities

The article presents some aspects of All-Union Sochi Resort quick pace construction in 1930s. Special attention is attached to official ideology and realities

Monitoring of Students` Professional Merits at the University

Constant system of monitoring of students` professionals merits is an effective instrument of quality evaluation in higher education. Different approaches to understanding of professional merits are considered in the article. The main professional merits are defined for professionals in the field of international relations. Results of monitoring of students` professional merits are described from first to fifth courses of international relations department. The second research is aimed to the professional merits of future teachers-students. The research demonstrates that the educational environment of university and especially designed and approved program of development of professional merits are important for formation of students` professional competence

Voto electrónico en la Rusia moderna: debates, tecnologías, experimentos

We discussed the increasing interest in the use of technical means for voting in elections and referendums with a gradual transition to electronic voting. Our article deals with the peculiarities of the experiment on the organization and conduct of remote electronic voting in the elections of deputies of the Moscow City Duma of the seventh convocation, scheduled for September 8, 2019. In addition, the article analyzes the advantages and disadvantages of electronic voting, offers recommendations on eliminating some risks associated with the use of this type of electronic voting. The received results of the experiment will allow to define directions of the further work on perfection of legal regulation of introduction in selective process of modern digital technologies. In case of positive results, practical and technological solutions can be developed, which will ensure further development of the remote electronic voting system in Russia.Discutimos el creciente interés en el uso de medios técnicos para votar en elecciones y referéndums con una transición gradual al voto electrónico. Nuestro artículo aborda las peculiaridades del experimento sobre la organización y la realización de la votación electrónica remota en las elecciones de diputados de la Duma de la ciudad de Moscú de la séptima convocatoria, prevista para el 8 de septiembre de 2019. Además, el artículo analiza las ventajas y desventajas de votación electrónica, ofrece recomendaciones para eliminar algunos riesgos asociados con el uso de este tipo de votación electrónica. Los resultados recibidos del experimento permitirán definir las direcciones del trabajo posterior sobre la perfección de la regulación legal de la introducción en el proceso selectivo de las tecnologías digitales modernas. En caso de resultados positivos, se pueden desarrollar soluciones prácticas y tecnológicas que garanticen un mayor desarrollo del sistema de votación electrónica remota en Rusia