El Niño and the related phenomenon Southern Oscillation (ENSO): The largest signal in interannual climate variation

El Niño and the related phenomenon Southern Oscillation (ENSO) is the strongest signal in the interannual variation of ocean-atmosphere system. It is mainly a tropical event but its impact is global. ENSO has been drawing great scientific attention in many international research programs. There has been an observational system for the tropical ocean, and scientists have known the climatologies of the upper ocean, developed some theories about the ENSO cycle, and established coupled ocean-atmosphere models to give encouraging predictions of ENSO for a 1-year lead. However, questions remain about the physical mechanisms for the ENSO cycle and its irregularity, ENSO-monsoon interactions, long-term variation of ENSO, and increasing the predictive skill of ENSO and its related climate variations.

Root-Growth Behavior of the Arabidopsis Mutant rgr11 : Roles of Gravitropism and Circumnutation in the Waving/Coiling Phenomenon

In this study we investigated the kinetics of the gravitropic response of the Arabidopsis mutant rgr1 (reduced root gravitropism). Although the rate of curvature in rgr1, which is allelic to axr4, was smaller than in the wild type (ecotype Wassilewskija), curvature was initiated in the same region of the root, the distal elongation zone. The time lag for the response was unaffected in the mutant; however, the gravitropic response of rgr1 contained a feature not found in the wild type: when roots growing along the surface of an agar plate were gravistimulated, there was often an upward curvature that initiated in the central elongation zone. Because this response was dependent on the tactile environment of the root, it most likely resulted from the superposition of the waving/coiling phenomenon onto the gravitropic response. We found that the frequency of the waving pattern and circumnutation, a cyclic endogenous pattern of root growth, was the same in rgr1 and in the wild type, so the waving/coiling phenomenon is likely governed by circumnutation patterns. The amplitudes of these oscillations may then be selectively amplified by tactile stimulation to provide a directional preference to the slanting.

The cutoff phenomenon in finite Markov chains.

Natural mixing processes modeled by Markov chains often show a sharp cutoff in their convergence to long-time behavior. This paper presents problems where the cutoff can be proved (card shuffling, the Ehrenfests' urn). It shows that chains with polynomial growth (drunkard's walk) do not show cutoffs. The best general understanding of such cutoffs (high multiplicity of second eigenvalues due to symmetry) is explored. Examples are given where the symmetry is broken but the cutoff phenomenon persists.

Homeologous recombination and mismatch repair during transformation in Streptococcus pneumoniae: saturation of the Hex mismatch repair system.

The ability of the Hex generalized mismatch repair system to prevent recombination between partially divergent (also called homeologous) sequences during transformation in Streptococcus pneumoniae was investigated. By using as donor in transformation cloned fragments 1.7-17.5% divergent in DNA sequence from the recipient, it was observed that the Hex system prevents chromosomal integration of the least and the most divergent fragments but frequently fails to do so for other fragments. In the latter case, the Hex system becomes saturated (inhibited) due to an excess of mismatches: it is unable to repair a single mismatch located elsewhere on the chromosome. Further investigation with chromosomal donor DNA, carrying only one genetically marked divergent region, revealed that a single divergent fragment can lead to saturation of the Hex system. Increase in cellular concentration of either HexA, the MutS homologue that binds mismatches, or HexB, the MutL homologue for which the essential role in repair as yet remains obscure, was shown to restore repair ability in previously saturating conditions. Investigation of heterospecific transformation by chromosomal DNA from two related streptococcal species, Streptococcus oralis and Streptococcus mitis, also revealed complete saturation of the Hex system. Therefore the Hex system is not a barrier to interspecies recombination in S. pneumoniae. These results are discussed in light of those described for the Mut system of Escherichia coli.

Evolution as a self-organized critical phenomenon.

We present a simple mathematical model of biological macroevolution. The model describes an ecology of adapting, interacting species. The environment of any given species is affected by other evolving species; hence, it is not constant in time. The ecology as a whole evolves to a "self-organized critical" state where periods of stasis alternate with avalanches of causally connected evolutionary changes. This characteristic behavior of natural history, known as "punctuated equilibrium," thus finds a theoretical explanation as a self-organized critical phenomenon. The evolutionary behavior of single species is intermittent. Also, large bursts of apparently simultaneous evolutionary activity require no external cause. Extinctions of all sizes, including mass extinctions, may be a simple consequence of ecosystem dynamics. Our results are compared with data from the fossil record.

Effect of magnetic activity saturation in chromospheric flux-flux relationships

We present a homogeneous study of chromospheric and coronal flux–flux relationships using a sample of 298 late-type dwarf active stars with spectral types F to M. The chromospheric lines were observed simultaneously in each star to avoid spread as a result of long-term variability. Unlike other works, we subtract the basal chromospheric contribution in all the spectral lines studied. For the first time, we quantify the departure of dMe stars from the general relations. We show that dK and dKe stars also deviate from the general trend. Studying the flux–colour diagrams, we demonstrate that the stars deviating from the general relations are those with saturated X-ray emission and we show that these stars also present saturation in the Hα line. Using several age spectral indicators, we show that these are younger stars than those following the general relationships. The non-universality of flux–flux relationships found in this work should be taken into account when converting between fluxes in different chromospheric activity indicators.

El medio en el mensaje: la autorreferencia en la televisión generalista

Los medios de comunicación, cuyas funciones clásicas eran «informar, formar y entretener», están dando protagonismo creciente a la autorreferencia, que es una forma abierta o encubierta de autopublicidad. El medio compromete espacios (en la prensa) o tiempos (formatos audiovisuales) para anunciarse a sí mismo, disminuyendo espacios y tiempos dedicados a mostrar realidades (o ficciones) que nada tienen que ver con el propio medio, y que son el mandato derivado de su dimensión social y cívica. El artículo analiza este fenómeno en televisión, con estudios empíricos sobre el registro de 24 horas continuadas de programación en las tres cadenas generalistas con más cuota d e pantalla. La novedad del estudio es 1) el análisis de la autorreferencia también dentro de los programas (y no sólo en los segmentos de continuidad declaradamente autopublicitarios: promociones, cortinillas, caretas, etc.) y 2) la atención a la autorreferencia como estrategia de cross-promotion entre medios del mismo grupo multimedia.

An improved procedure for obtaining and maintaining well characterized partial water saturation states on concrete samples to be used for mass transport tests

A conditioning procedure is proposed allowing to install into the concrete specimens any selected value of water saturation degree with homogeneous moisture distribution. This is achieved within the least time and the minimum alteration of the concrete specimens. The protocol has the following steps: obtaining basic drying data at 50 °C (water absorption capacity and drying curves); unidirectional drying of the specimens at 50 °C until reaching the target saturation degree values; redistribution phase in closed containers at 50 °C (with measurement of the quasi-equilibrium relative humidities); storage into controlled environment chambers until and during mass transport tests, if necessary. A water transport model is used to derive transport parameters of the tested materials from the drying data, i.e., relative permeabilities and apparent water diffusion coefficients. The model also allows calculating moisture profiles during isothermal drying and redistribution phases, thus allowing optimization of the redistribution times for obtaining homogeneous moisture distributions.

The action cam phenomenon: a new trend in audiovisual production

When the GoPro camera was first put on the market in 2004, it brought about a new generation of ultracompact cameras designed to be attached to the user’s body, and which came to be known as action cams. Their principal characteristics were their tiny size, their high-quality images and a wide-angle, fixed-focal-length lens. This combination has made it much simpler to get spectacular subjective shots with considerable depth of field. The users of this technology now form a whole generation of citizen-filmmakers who produce thousands of videos every day in a novel realistic style dominated by first-person narrative. Their work is principally shared via video platforms like YouTube and Vimeo, which provide instant feedback in the form of millions of views. In this paper we analize the common features of the action cam recording style and we state these videos will bring about a redefinition of the realist visual style. Furthermore, we propose to relate the success of the action cam phenomenon with the cognitive concept of embodiment and argue that the viewer’s mirror neurons copy the real sensations and enable the viewer to experience, virtually and in safety, the same emotions felt by the person actually taking part in the action.

Give me a shilling [videorecording]: phenomenon of the street children

Pictures of the Watoto wa Lwanga project, the efforts of the Brothers of St. Charles Lwanga not only to rehabilitate Nairobi's street children, but to prevent slum children from ending up in the streets. Features life in the slums, the situation of the street children, the efforts of the social workers to involve the children's parents, the various reception centers, the vocational school, the Boy's Town Ruai Residential School, the community of the Brothers of St. Charles Lwanga as well as interviews with former street children and with various directors and benefactors of the project.

Svodboda party - the new phenomenon on the Ukrainian right-wing scene. OSW Commentary No. 56, 2011-07-04

Even though the national-level political scene in Ukraine is dominated by the Party of Regions, the west of the country has seen a progressing increase in the activity of the Svoboda (Freedom) party, a group that combines participation in the democratically elected local government of Eastern Galicia with street actions, characteristic of anti-system groups. This party has brought a new quality to the Ukrainian nationalist movement, as it refers to the rhetoric of European anti-liberal and neo-nationalist movements, and its emergence is a clear response to public demand for a group of this sort. The increase in its popularity plays into the hands of the Party of Regions, which is seeking to weaken the more moderate opposition parties (mainly the Yulia Tymoshenko Bloc). However, Svoboda retains its independence from the ruling camp. This party, in all likelihood, will become a permanent and important player in Ukrainian political life, although its influence may be restricted to Eastern Galicia. Svoboda is determined to fight the tendencies in Ukrainian politics and the social sphere which it considers pro-Russian. Its attitude towards Russia and Russians, furthermore, is unambiguously hostile. In the case of Poland, it reduces mutual relations almost exclusively to the historical aspects, strongly criticising the commemoration of the victims of the Ukrainian Insurgent Army’s (UPA) crimes. This may cause tension in Polish-Ukrainian relations, where they are affected by decisions made by local governments controlled by the Svoboda Party.

Homo Jihadicus. Islam in the former USSR and the phenomenon of the post-Soviet militants in Syria and Iraq. OSW REPORT 2015-09-21

The post-Soviet area, along with the countries of the Middle East, North Africa and Western Europe, have become one of the main global exporters of Islamic militants. Currently on the territory of Syria, and to a lesser extent of Iraq, there are several thousands of foreign fighters from the post-Soviet states. The causes of the war migration from the former USSR states to the Middle East have their roots in the dynamic changes taking place inside Islam in the post-Soviet area: primarily the growth of Salafism and militant Islam, as well as the internationalisation and globalisation of the local Islam. The deep political, economic, social and ideological changes which Muslims underwent after the collapse of the USSR, led to the creation of a specific group within them, for which Islam in its radical form became the main element of their identity. Homo sovieticus, without fully eradicating his Soviet part, became Homo jihadicus who not only identifies himself with the global Ummah, but is also ready to leave his country and join jihad beyond its borders in the name of the professed ideas.