Intra-specific variability and unusual organization of the repetitive units in a satellite DNA from Rana dalmatina: molecular evidence of a new mechanism of DNA repair acting on satellite DNA.

We have characterized the S1 satellite from eight European populations of Rana dalmatina by Southern blot, cloning and a new method that determines the sequence variability of repetitive units in the genome. This report completes our previous studies on this satellite DNA family, thus providing the first characterization of the overall variability of the structure and genomic organization of a satellite DNA within a species and among related species. The S1 satellite from R. dalmatina has a pericentromeric location on ten chromosome pairs and presents two homologous repeats S1a (494 bp) and S1b (332 bp), mostly organized as composite S1a-S1b repetitive units. In other brown frog species, both repeats have different sequences and locations, and are usually organized as separate arrays, although composite S1a-S1b repeats represent a minor, widely variable component in Rana italica. The average genomic sequences indicate that the species contains an enormous number of variants of each repeat derived from a unique, species-specific common sequence. The repeat variability is restricted to specific base changes in specific sequence positions in all population samples. Our data show that the structure and evolution of S1 satellite family is not due to crossing-over and gene conversion, but to a mechanism that maintains the ability of the satellite DNA to assemble in constitutive heterochromatin by replacing altered satellite segments with new arrays generated by rolling circle amplification. The mode of action of this repair process not only directly explains the intra- and inter-specific variability of the structure and organization of the S1 satellite repeats from European brown frogs, but also accounts for all general features of satellite DNA in eukaryotes, including its discontinuous evolution. This repair mechanism can maintain the satellite structure in a species indefinitely, but also promote a rapid generation of new variants or types of satellite DNA when environmental conditions favor the formation of new species

Las aguas brillantes de Corrientes

Fil: Orfeo, Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Mechano-Magnetic Telemetry For Urban Infrastructure Monitoring

Many cities seek utilities monitoring with centrally managed Internet of Things (IoT) systems. This requires the development of numerous reliable low-cost wireless sensors, such as water temperature and flow meters, that can transmit information from subterranean pipes to surface-mounted receivers. Traditional radio communication systems are either unable to penetrate through multiple feet of earthen and manmade material, or have impractically large energy requirements which necessitate either frequent replacement of batteries, or a complex (and expensive) built-in energy harvesting system. Magnetic signaling systems do not suffer from this drawback: low-frequency electromagnetic waves have been shown to penetrate well through several feet of earth and water. In the past, these signals were too weak for practical use; however, this has changed with the recent proliferation of high-sensitivity magnetometers and compact rare-earth magnets. A permanent magnet can be either rotated or vibrated to create an oscillating magnetic field. Utilizing this phenomenon, two types of magnetic transmitter are investigated in this study: one which uses a propeller to directly rotate a diametrically magnetized neodymium magnet; and a second in which a permanent magnet is oscillated back-and-forth across a novel soft-magnet Y-stator, which projects a switching magnetic field. In principle, these oscillating magnetic fields can be used for communication from subterranean infrastructure sensors—such as flow meters and leak detection devices—to an aboveground long range (LoRa) radio-networked Arduino receiver equipped with a magnetometer. Simulation software models the oscillating electromagnetic fields produced by the Y-stator configuration. Laboratory performance and field tests establish the capability of two IoT-linked leak-detection sensors that use magnetic telemetry. Remote datalogging demonstrates the viability of integrating many sensors and surface receivers into a single LoRa wireless IoT network

AUTOMATIZZAZIONE E CONTROLLO DEI DISPOSITIVI POS

- Realizzazione operazioni atomatiche per il progetto Unipos. - Realizzazione piattaforma di controllo remoto hardware e software dei dispositivi POS

El movimiento olímpico frente a la violación institucional de derechos

El Olimpismo moderno no es únicamente un movimiento deportivo, sino que fue concebido por su fundador, Pierre de Coubertin, con un objetivo moral. El compromiso con la "dignidad humana" y los "principios éticos universales" están recogidos en la Carta Olímpica, que regula su funcionamiento. En ellos se incide en el rechazo a cualquier tipo de discriminación. A pesar de ello, el Comité Olímpico Internacional (COI), su órgano de gobierno, no siempre ha cumplido con estos postulados cuando se ha encontrado con violaciones de derechos por parte países integrados en su organización, a través de sus comités olímpicos nacionales, o de organizadores de su competición, los Juegos Olímpicos. El artículo analiza cuatro modelos de actuación por parte del COI a lo largo de su historia frente a la violación de derechos a partir de cuatro escenarios: la connivencia en los Juegos de Berlín 1936, la tolerancia en los Juegos de Pekín 2008, la sanción contra la Sudáfrica del apartheid y la sanción y la negociación, indistintamente, frente a los países del Islam que discriminan a la mujer en el deporte.El Olimpismo moderno no es únicamente un movimiento deportivo, sino que fue concebido por su fundador, Pierre de Coubertin, con un objetivo moral. El compromiso con la "dignidad humana" y los "principios éticos universales" están recogidos en la Carta Olímpica, que regula su funcionamiento. En ellos se incide en el rechazo a cualquier tipo de discriminación. A pesar de ello, el Comité Olímpico Internacional (COI), su órgano de gobierno, no siempre ha cumplido con estos postulados cuando se ha encontrado con violaciones de derechos por parte países integrados en su organización, a través de sus comités olímpicos nacionales, o de organizadores de su competición, los Juegos Olímpicos. El artículo analiza cuatro modelos de actuación por parte del COI a lo largo de su historia frente a la violación de derechos a partir de cuatro escenarios: la connivencia en los Juegos de Berlín 1936, la tolerancia en los Juegos de Pekín 2008, la sanción contra la Sudáfrica del apartheid y la sanción y la negociación, indistintamente, frente a los países del Islam que discriminan a la mujer en el deporteEl Olimpismo moderno no es únicamente un movimiento deportivo, sino que fue concebido por su fundador, Pierre de Coubertin, con un objetivo moral. El compromiso con la "dignidad humana" y los "principios éticos universales" están recogidos en la Carta Olímpica, que regula su funcionamiento. En ellos se incide en el rechazo a cualquier tipo de discriminación. A pesar de ello, el Comité Olímpico Internacional (COI), su órgano de gobierno, no siempre ha cumplido con estos postulados cuando se ha encontrado con violaciones de derechos por parte países integrados en su organización, a través de sus comités olímpicos nacionales, o de organizadores de su competición, los Juegos Olímpicos. El artículo analiza cuatro modelos de actuación por parte del COI a lo largo de su historia frente a la violación de derechos a partir de cuatro escenarios: la connivencia en los Juegos de Berlín 1936, la tolerancia en los Juegos de Pekín 2008, la sanción contra la Sudáfrica del apartheid y la sanción y la negociación, indistintamente, frente a los países del Islam que discriminan a la mujer en el deporte

A Perspective on the Experimental Techniques for Studying Lamins

3Lamins are type V intermediate filaments that collectively form a meshwork underneath the inner nuclear membrane, called nuclear lamina. Furthermore, they are also present in the nucleoplasm. Lamins are experiencing a growing interest, since a wide range of diseases are induced by mutations in the gene coding for A-type lamins, globally known as laminopathies. Moreover, it has been demonstrated that lamins are involved in other pathological conditions, like cancer. The role of lamins has been studied from several perspectives, exploiting different techniques and procedures. This multidisciplinary approach has contributed to resolving the unique features of lamins and has provided a thorough insight in their role in living organisms. Yet, there are still many unanswered questions, which constantly generate research in the field. The present work is aimed to review some interesting experimental techniques performed so far to study lamins. Scientists can take advantage of this collection for their novel investigations, being aware of the already pursued and consolidated methodologies. Hopefully, advances in these research directions will provide insights to achieve better diagnostic procedures and effective therapeutic options.openopenPecorari, Ilaria; Borin, Daniele; Sbaizero, OrfeoPecorari, Ilaria; Borin, Daniele; Sbaizero, Orfe

The first characterisation of the overall variability of repetitive units in a species reveals unexpected features of satellite DNA.

We investigated the overall variability of the S1a satellite DNA repeats in ten European populations of Rana temporaria by a new procedure that determines the average sequence of the repeats in a genome. The average genomic sequences show that only 17% of the S1a repeat sequence (494 bp) is variable. The variable positions contain the same major and minor bases in all or many of the population samples tested, but the percentages of these bases can greatly vary among populations. This indicates the presence in the species of an enormous number of repeats having a different distribution of bases in these variable positions. Individual genomes contain thousands of repeat variants, but these mixtures have very similar characteristics in all populations because they present the same type of restricted and species-specific variability. Southern blots analyses and sequences of cloned S1a repeats fully support this conclusion. The S1 satellite DNA of other European brown frog species also presents properties indicating the same type of variability. This first characterisation of the overall repeat variability of a satellite DNA in a species has revealed features that cannot be determined by gene conversion and crossing over. Our results suggest that a specific directional process based on rolling circle amplification should play a relevant role in the evolution of satellite DNA