Synchronization from Disordered Driving Forces in Arrays of Coupled Oscillators

The effects of disorder in external forces on the dynamical behavior of coupled nonlinear oscillator networks are studied. When driven synchronously, i.e., all driving forces have the same phase, the networks display chaotic dynamics. We show that random phases in the driving forces result in regular, periodic network behavior. Intermediate phase disorder can produce network synchrony. Specifically, there is an optimal amount of phase disorder, which can induce the highest level of synchrony. These results demonstrate that the spatiotemporal structure of external influences can control chaos and lead to synchronization in nonlinear systems.Comment: 4 pages, 4 figure

Interiors and furnishings designed by Miguel Fisac for the CSIC

[ES] Conocida y fotografiada parte de la producción de Miguel Fisac relacionada con el mobiliario para el CSIC, no había sido estudiada hasta ahora en su conjunto. Se recogen cronológicamente los diferentes estilos utilizados para los distintos espacios, las motivaciones expresadas por el propio arquitecto, su estado actual y las consideraciones que puedan permitir su inclusión en el Patrimonio Artístico del CSIC y la declaración de alguna de ellas, como la “librería científica” como Bien de Interés Cultural.[EN] Although Miguel Fisac’s designs for the furnishings in the Spanish Council for Scientific Research are well known and widely photographed, they had not, to date, been studied as a whole. This chronological review of the styles used to create different spatial effects describes both the author’s motivations as explained by the architect himself and the present condition of the furnishings. Considerations in support of their inclusion in the Council’s Artistic Estate are discussed, advocating —in the case of the “Scientific Library”— the award of Asset of Cultural Interest status.Peer reviewe

Neocortical activity is stimulus- and scale-invariant

Mounting evidence supports the hypothesis that the cortex operates near a critical state, defined as the transition point between order (large-scale activity) and disorder (small-scale activity). This criticality is manifested by power law distribution of the size and duration of spontaneous cascades of activity, which are referred as neuronal avalanches. The existence of such neuronal avalanches has been confirmed by several studies both in vitro and in vivo, among different species and across multiple spatial scales. However, despite the prevalence of scale free activity, still very little is known concerning whether and how the scale-free nature of cortical activity is altered during external stimulation. To address this question, we performed in vivo two-photon population calcium imaging of layer 2/3 neurons in primary visual cortex of behaving mice during visual stimulation and conducted statistical analyses on the inferred spike trains. Our investigation for each mouse and condition revealed power law distributed neuronal avalanches, and irregular spiking individual neurons. Importantly, both the avalanche and the spike train properties remained largely unchanged for different stimuli, while the cross-correlation structure varied with stimuli. Our results establish that microcircuits in the visual cortex operate near the critical regime, while rearranging functional connectivity in response to varying sensory inputs

Сведения об авторах

Представлены в алфавитном порядке авторы и области их научных интересов, контактная информация

Distributed delays stabilize neural feedback systems

We consider the effect of distributed delays in neural feedback systems. The avian optic tectum is reciprocally connected with the nucleus isthmi. Extracellular stimulation combined with intracellular recordings reveal a range of signal delays from 4 to 9 ms between isthmotectal elements. This observation together with prior mathematical analysis concerning the influence of a delay distribution on system dynamics raises the question whether a broad delay distribution can impact the dynamics of neural feedback loops. For a system of reciprocally connected model neurons, we found that distributed delays enhance system stability in the following sense. With increased distribution of delays, the system converges faster to a fixed point and converges slower toward a limit cycle. Further, the introduction of distributed delays leads to an increased range of the average delay value for which the system's equilibrium point is stable. The enhancement of stability with increasing delay distribution is caused by the introduction of smaller delays rather than the distribution per se.Comment: 7 pages, 4 figure

Технологические решения для строительства разведочной вертикальной скважины глубиной 3110 метров на газовом месторождении (Тюменская область)

Технологические решения для строительства разведочной вертикальной скважины глубиной 3100 метров на нефтяном месторождении (Тюменской области).Technological solutions for the construction of an exploratory vertical well depth of 3110 meters at an oil field (Tumen region)

Технологические решения для строительства разведочной вертикальной скважины глубиной 2200 метров на нефтяном месторождении (Томская область)

Цель работы — проектирование и строительства разведочной скважины глубиной 2200 метров. В процессе работы был составлен проект на строительство разведочной скважины на глубиной 2200 м. Разработаны мероприятия по организации строительству, охране труда и окружающей среды. В работе рассмотрен вопрос о возможности применения яссов. Дипломная работа выполнена с учетом современных достижений в области техники и технологии строительства нефтяных скважин.The purpose of the work is the design and construction of an exploration well with a depth of 2,200 meters. In the process, a project was drawn up for the construction of an exploration well at a depth of 2,200 m. Developed measures for the organization of construction, labor and environmental protection. The paper considered the possibility of using jars. The diploma work was carried out taking into account modern achievements in the field of engineering and technology of construction of oil wells

Intraoperative Beat-to-Beat Pulse Transit Time (PTT) Monitoring via Non-Invasive Piezoelectric/Piezocapacitive Peripheral Sensors Can Predict Changes in Invasively Acquired Blood Pressure in High-Risk Surgical Patients

Background: Non-invasive tracking of beat-to-beat pulse transit time (PTT) via piezoelectric/piezocapacitive sensors (PES/PCS) may expand perioperative hemodynamic monitoring. This study evaluated the ability for PTT via PES/PCS to correlate with systolic, diastolic, and mean invasive blood pressure (SBPIBP, DBPIBP, and MAPIBP, respectively) and to detect SBPIBP fluctuations. Methods: PES/PCS and IBP measurements were performed in 20 patients undergoing abdominal, urological, and cardiac surgery. A Pearson’s correlation analysis (r) between 1/PTT and IBP was performed. The predictive ability of 1/PTT with changes in SBPIBP was determined by area under the curve (reported as AUC, sensitivity, specificity). Results: Significant correlations between 1/PTT and SBPIBP were found for PES (r = 0.64) and PCS (r = 0.55) (p < 0.01), as well as MAPIBP/DBPIBP for PES (r = 0.6/0.55) and PCS (r = 0.5/0.45) (p < 0.05). A 7% decrease in 1/PTTPES predicted a 30% SBPIBP decrease (0.82, 0.76, 0.76), while a 5.6% increase predicted a 30% SBPIBP increase (0.75, 0.7, 0.68). A 6.6% decrease in 1/PTTPCS detected a 30% SBPIBP decrease (0.81, 0.72, 0.8), while a 4.8% 1/PTTPCS increase detected a 30% SBPIBP increase (0.73, 0.64, 0.68). Conclusions: Non-invasive beat-to-beat PTT via PES/PCS demonstrated significant correlations with IBP and detected significant changes in SBPIBP. Thus, PES/PCS as a novel sensor technology may augment intraoperative hemodynamic monitoring during major surgery.German Government sponsored ZIM (Zentrales Innovationsprogramm Mittelstand) programPeer Reviewe