Captures of Hot and Warm Sterile Antineutrino Dark Matter on EC-decaying Ho-163 Nuclei

Capturing low-energy electron antineutrinos on radioactive Ho-163 nuclei, which decay into Dy-163 via electron capture (EC), is a noteworthy opportunity to detect relic sterile antineutrinos. Such hypothetical particles are more or less implied by current experimental and cosmological data, and they might be a part of hot dark matter or a candidate for warm dark matter in the Universe. Using the isotope Ho-163 as a target and assuming reasonable active-sterile antineutrino mixing angles, we calculate the capture rate of relic electron antineutrinos against the corresponding EC-decay background in the presence of sterile antineutrinos at the sub-eV or keV mass scale. We show that the signature of hot or warm sterile antineutrino dark matter should in principle be observable, provided the target is big enough and the energy resolution is good enough.Comment: 16 pages, 6 figures, more discussions and references added. To appear in JCA

Self-optimisation of admission control and handover parameters in LTE

In mobile cellular networks the handover (HO) algorithm is responsible for determining when calls of users that are moving from one cell to another are handed over from the former to the latter. The admission control (AC) algorithm, which is the algorithm that decides whether new (fresh or HO) calls that enter a cell are allowed to the cell or not, often tries to facilitate HO by prioritising HO calls in favour of fresh calls. In this way, a good quality of service (QoS) for calls that are already admitted to the network is pursued. In this paper, the effect of self-optimisation of AC parameters on the HO performance in a long term evolution (LTE) network is studied, both with and without the self-optimisation of HO parameters. Simulation results show that the AC parameter optimisation algorithm considerably improves the HO performance by reducing the amount of calls that are dropped prior to or during HO

Higher-order theories of consciousness and what-it-is-like-ness

Ambitious higher-order theories of consciousness aim to account for conscious states when these are understood in terms of what-it-is-like-ness. This paper considers two arguments concerning this aim, and concludes that ambitious theories fail. The misrepresentation argument against HO theories aims to show that the possibility of radical misrepresentation—there being a HO state about a state the subject is not in—leads to a contradiction. In contrast, the awareness argument aims to bolster HO theories by showing that subjects are aware of all their conscious states. Both arguments hinge on how we understand two related notions which are ubiquitous in discussions of consciousness: those of what-it-is-like-ness and there being something it is like for a subject to be in a mental state. This paper examines how HO theorists must understand the two crucial notions if they are to reject the misrepresentation argument but assert the awareness argument. It shows that HO theorists can and do adopt an understanding—the HO reading—which seems to give them what they want. But adopting the HO reading changes the two arguments. On this reading, the awareness argument tells us nothing about those states there is something it is like to be in, and so offers no support to ambitious HO theories. And to respond to the misrepresentation understood according to the HO reading is to simply ignore the argument presented, and so to give no response at all. As things stand, we should deny that HO theories can account for what-it-is-like-ness

Michael Handelsman: estudioso, archivero y crítico de la prosa literaria escrita por mujeres en Ecuador (Tributo)

This paper intends to recognize and highlight the outstanding input made by critic Michael Handelsman in his study on narrative (both essayistic and fictional) written by women in Ecuador. It is important to highlight the scope of a work committed to place women’s writing in the cultural and political sphere and show its impact on the public and social scene, in the horizon of its production, circulation and reception possibilities. Handelsman’s writings (where he studies essays, novels, short stories and magazines written by Ecuadorian women) are approached with the purpose of observing his reading strategies, which lead him to conceive Literature as a struggle scenario for female writers: a space of self-representation, resistance and production of knowledge, in tension with a system of patriarchal values. Above all, this paper is a tribute to the task continually performed by Michael Handelsman for some decades, with generosity and lucidity, in the search and construction of the corpus that constitutes its object of study. It is a corpus scattered through libraries, archives, magazines, anthologies, which Handelsman has located, attended to, taken care of, systematized, periodized, valued, placed for debate, generated affiliations therewith, always insisting on the existence and scope of the valuable –and sometimes forgotten narrative tradition– produced in Ecuador by female writers.Este trabajo tiene como propósito reconocer y destacar el notable aporte realizado por el crítico Michael Handelsman en el estudio de la narrativa (ensayística y de ficción) escrita por mujeres en Ecuador. Interesa resaltar los alcances de una labor empeñada en situar la escritura de mujeres en el terreno de la esfera cultural y política, de su impacto en la escena pública y social, en el horizonte de sus condiciones de posibilidad de producción, así como de circulación y recepción. Los escritos de Handelsman son atendidos (en los que estudia ensayos, novelas, cuentos y revistas escritas por mujeres ecuatorianas) con el propósito de observar sus estrategias de lectura que lo llevan a pensar la literatura como un escenario de lucha para las mujeres escritoras: espacio de autorepresentación, de resistencia y producción de conocimiento, en tensión con un sistema de valores de origen patriarcal. Sobre todo, este trabajo es un homenaje y tributo a la tarea que Michael Handelsman ha desempeñado de manera sostenida durante algunas décadas, con generosidad y lucidez en la búsqueda y construcción de su corpus objeto de estudio. Un corpus disperso en bibliotecas, archivos, revistas, antologías, que Handelsman ha sabido ubicar, atender, cuidar, sistematizar, periodizar, valorar, poner en debate, generar filiaciones e insistentemente señalar la existencia y alcances de esa valiosa, y a veces olvidada tradición narrativa producida en Ecuador por escritoras mujeres

Зависимость физико-химических свойств ВТСП-соединений от размера кристаллитов

Керамическим методом с предварительным получением прекурсора синтезированы материалы состава Bi2Sr2Ca1−xLnxCu2Oу (Ln – La, Nd, Y, Ho, Lu) и Bi2Sr2−xLnxCaCu2Oу (Ln – La, Nd, Ho, Lu). Исследованы микроструктура, область гомогенности, электрофизические характеристики, кислородная стехиометрия систем Bi2Sr2Ca1−xLnxCu2Oу (Ln – La, Nd, Y, Ho, Lu) и Bi2Sr2−xLnxCaCu2Oу (Ln – La, Nd, Ho, Lu) в зависимости от степени замещения х и температуры перехода в сверхпроводящее состояние Тсon. Изучено влияние условий термической обработки на размеры кристаллитов, величину кислородного индекса и критическую температуру. Получены наноразмерные частицы (Dср = 0,5—1,5 мкм). Показано, что границы области гомогенности уменьшаются от 0 ≤ x ≤ 0,3 по Lu3+ к 0 ≤ x ≤ 0,05 по La3+.Керамічною методою з попереднім одержанням прекурсору синтезовано матеріяли складу Bi2Sr2Ca1−xLnxCu2Oу (Ln – La, Nd, Y, Ho, Lu) та Bi2Sr2−xLnxCaCu2Oу (Ln – La, Nd, Ho, Lu). Досліджено мікроструктуру, область гомогенности, електрофізичні характеристики й кисневу стехіометрію систем Bi2Sr2Ca1−xLnxCu2Oу (Ln – La, Nd, Y, Ho, Lu) і Bi2Sr2−xLnxCaCu2Oу (Ln – La, Nd, Ho, Lu) залежно від ступеня заміщення х та температури переходу в надпровідний стан Тсon. Вивчено вплив умов термічного оброблення на розмір зерна, величину кисневого індексу та критичну температуру. Одержано нанорозмірні частинки (Dсер = 0,5—0,15 мкм). Показано, що межі гомогенности зменшуються від 0 ≤ x ≤ 0,3 за Lu3+ до 0 ≤ x ≤ 0,05 за La3+.The samples of Bi2Sr2Ca1−xLnxCu2Oу (Ln–La, Nd, Y, Ho, Lu) and Bi2Sr2−xLnxCaCu2Oу (Ln–La, Nd, Ho, Lu) are synthesized using the ceramic technique with precursor. For Bi2Sr2Ca1−xLnxCu2Oy (Ln–La, Nd, Y, Ho, Lu) and Bi2Sr2−xLnxCaCu2Oу (Ln–La, Nd, Ho, Lu) systems, the dependences of microstructure, homogeneity region, electrophysical properties, and oxygen nonstoichiometry on their composition (x) and Tcon value are studied. Influence of heat-treatment conditions on the sizes of crystallites, value of oxygen index, and critical temperature is studied. As shown, the homogeneity region becomes narrower when going from 0 ≤ x ≤ 0.3 for Lu3+ to 0 ≤ x ≤ 0.05 for La3+

La sencilla lucidez de Pedro Jorge Vera. Notas a propósito de su cuentística (Homenaje)

A privileged genre in Latin America, short stories have had, and still have, highly esteemed cultivators in the region such as the late Ecuadorian writer Pedro Jorge Vera, a creator whose birth centennial is celebrated in 2014, on the occasion of which this paper examines some of his most important stories in order to highlight their humanistic and denunciatory will of the social injustices and prejudices suffered by the poorest and least privileged sectors of Latin America. With their lucid simplicity, Vera’s stories stand out for the stylistic organicity of their writing, the broad thematic spectrum and the rich range of narrative procedures which very effectively convey the charges of the stories told. Distinctive features of this manner of proceeding are the fully developed, the rapid progress of the action and compact structure, the unpredictability of their outcomes, the sobriety and accuracy of the narrative discourse, the decisive role of deconstructive procedures and preference for problematic, contradictory characters.Género privilegiado en América Latina, el cuento ha tenido y tiene cultores de alta estima en la región como el desaparecido escritor ecuatoriano Pedro Jorge Vera, creador cuyo centenario de nacimiento se celebra en este 2014, y con motivo del cual el presente ensayo examina algunos de sus cuentos más importantes con el propósito de destacar su definida voluntad humanista y denunciatoria de las injusticias y prejuicios sociales padecidos por los sectores más humildes o menos privilegiados de América Latina. Exponentes de una poética de lúcida sencillez, los cuentos de Vera sobresalen por la organicidad estilística de su escritura, el amplio espectro temático y la rica gama de procedimientos narrativos que vehiculan con suma eficacia los encargos de las historias narradas. Rasgos distintivos de ese proceder son los comienzos en pleno desarrollo, el rápido progreso de la acción y compacta estructura, la imprevisión de sus desenlaces, la sobriedad y precisión del discurso narrativo, el papel decisivo de procedimientos deconstructores y la preferencia por personajes problemáticos, contradictorios