Preseismic ULF electromagnetic effect from observation at Kamchatka

International audienceSome results of ULF magnetic field observation at Karimshino site (Kamchatka, Russia) since June 2000 to September 2001 are presented here. Using case study we have found an effect of suppression of ULF intensity about 2?6 days before rather strong and nearby seismic shocks (magnitude M = 4.0 ? 6.2). It is revealed for nighttime and horizontal component of ULF field (G) in the frequency range 0.01 ? 0.1 Hz. Then we prove the reliability of the effect by computed correlation between G (or 1/G) and specially calculated seismic indexes Ks for the whole period of observation. Basing on the simple criteria we conclude that reliability of seismo-associated ULF suppression effect is comparable with well-known effect of connection between ULF variation and Kp index of global magnetic activity. It seems the reason of suppression is located at the atmosphere or ionosphere but not in the ground medium

Mass Transfer Mechanism in Real Crystals by Pulsed Laser Irradiation

The dynamic processes in the surface layers of metals subjected activity of a pulsing laser irradiation, which destroyed not the crystalline structure in details surveyed. The procedure of calculation of a dislocation density generated in bulk of metal during the relaxation processes and at repeated pulse laser action is presented. The results of evaluations coincide with high accuracy with transmission electron microscopy dates. The dislocation-interstitial mechanism of laser-stimulated mass-transfer in real crystals is presented on the basis of the ideas of the interaction of structure defects in dynamically deforming medium. The good compliance of theoretical and experimental results approves a defining role of the presented mechanism of mass transfer at pulse laser action on metals. The possible implementation this dislocation-interstitial mechanism of mass transfer in metals to other cases of pulsing influences is justifiedComment: 10 pages, 2 figures, Late

Management of patients with acquired valvular heart disease in noncardiac surgery

Valvular heart disease is widespread among general population, mainly in older age groups, who often require noncardiac surgery. As the population ages, the significance of this problem will only increase. The basic principles of perioperative managing such patients by a multidisciplinary team, necessarily including a cardiologist, are systematized and set out in international clinical guidelines, which are regularly updated. Currently, the Russian Society of Cardiology guidelines on management of valvular heart diseases are being prepared for publication. However, specifics of assessment and management of patients when planning noncardiac surgery require more detailed presentation for a cardiology practitioner

Do we know the actual magnetopause position for typical solar wind conditions?

We compare predicted magnetopause positions at the subsolar point and four reference points in the terminator plane obtained from several empirical and numerical MHD models. Empirical models using various sets of magnetopause crossings and making different assumptions about the magnetopause shape predict significantly different magnetopause positions (with a scatter >1 RE) even at the subsolar point. Axisymmetric magnetopause models cannot reproduce the cusp indentations or the changes related to the dipole tilt effect, and most of them predict the magnetopause closer to the Earth than nonaxisymmetric models for typical solar wind conditions and zero tilt angle. Predictions of two global nonaxisymmetric models do not match each other, and the models need additional verification. MHD models often predict the magnetopause closer to the Earth than the nonaxisymmetric empirical models, but the predictions of MHD simulations may need corrections for the ring current effect and decreases of the solar wind pressure that occur in the foreshock. Comparing MHD models in which the ring current magnetic field is taken into account with the empirical Lin et al. model, we find that the differences in the reference point positions predicted by these models are relatively small for Bz=0. Therefore, we assume that these predictions indicate the actual magnetopause position, but future investigations are still needed.Key PointsEmpirical models predict significantly different magnetopause positions even at the subsolar pointAxisymmetric empirical models predict the magnetopause closer to the Earth than nonaxisymmetric empirical models for zero tilt angleResults of MHD models with the ring current magnetic field lie close to results of the nonaxisymmetric Lin et al. modelPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134087/1/jgra52758_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134087/2/jgra52758.pd

Disturbances in groundwater chemical parameters related to seismic and volcanic activity in Kamchatka (Russia)

International audienceStarting from 1992 geochemical data are being collected with a mean sampling frequency of three days in the form of the pH value and of the most common ions and gases in the groundwater in one deep well located in Petropavlovsk, the capital city of Kamchatka (Russia). On 1 January 1996 a strong eruption started from the Karymsky volcano, that is located about 100km far from the well, in the north-northeastern direction. At the same time, a large earthquake (M=6.9) occurred in the Karymsky area. On 5 December 1997 a very large earthquake (M=7.7) occurred offshore, at a distance of 350km from the well and towards the same direction. The analysis of the geochemical data shows clear variations in the raw temporal trends on both cases. For the first event, a clear premonitory phase appeared; for the second one, some pre-seismic variations could be revealed but permanent modifications of the chemistry of the water subsequent to the earthquake are very clear. In both cases the feature of the geochemical variations is consistent with an afflux of new water in the aquifer connected with the well and with an escape of the Carbon dioxide gas from the ground in different directions. A schematic model able to justify such a phenomenology and the connections of the geochemical variations with the previous tectonic activities is proposed

About possibility to locate an EQ epicenter using parameters of ELF/ULF preseismic emission

A relation between parameters of preseismic ULF/ELF emissions and EQ is studied. The magnetic data measured at Karymshino station (Kamchatka, Russia) along with data on local seismic activity during eight years of observations (2001–2008) are taken for the analysis. Source azimuth is detected in different techniques, based on the analysis of the total field and its polarized pulsed component. The latter technique shows a better accuracy in the source azimuth detection. The errors of the method are associated with existence of non-seismic sources and with use of one-point observation. The second error can be eliminated by development of multi-point observations

Flow Induced Organization and Memory of a Vortex Lattice

We report on experiments probing the evolution of a vortex state in response to a driving current in 2H-NbSe$_2$ crystals. By following the vortex motion with fast transport measurements we find that the current enables the system to reorganize and access new configurations. During this process the system exhibits a long-term memory: if the current is turned off the vortices freeze in place remembering their prior motion. When the current is restored the motion resumes where it stopped. The experiments provide evidence for a dynamically driven structural change of the vortex lattice and a corresponding dynamic phase diagram that contains a previously unknown regime where the critical current can be either $increased$ or $decreased$ by applying an appropriate driving current.Comment: 5 pages, 4figure

Retrospective analysis for detecting seismic precursors in groundwater argon content

We examined the groundwater Argon content data sampled from 1988 to 2001 at two wells in Kamchatka (Russia) and anomalous increases appeared clearly during June-July&nbsp;1996. On 21&nbsp;June, a shallow (1km) earthquake with <i>M</i>=7.1 occurred at a distance less than 250km from the wells and so the previous increases could be related to this earthquake and, in particular, could be considered premonitory anomalies. In order to support this raw interpretation, we analysed the data collected in details. At first we smoothed out the high frequency fluctuations arising from the errors in a single measurement. Next we considered the known external effects on the water of a well that are the slow tectonic re-adjustment processes, the meteorology and the gravity tides and we separated these effects applying band-pass filters to the Argon content raw trends. Then we identified the largest fluctuations in these trends applying the 3 σ criterion and we found three anomalies in a case and two anomalies in other case. Comparing the time occurrence of the anomalies at the two wells we found out that a coincidence exists only in the case of the premonitory anomalies we are studying. The simultaneous appearance of well definite anomalies in the residual trends of the same parameter at two different sites supports their meaning and the possibility that they are related to some large scale effect, as the occurrence of a strong earthquake. But, other earthquakes similar to the June&nbsp;1996 event took place during the Argon content measurements time and no anomaly appeared in this content. In the past, some of the authors of this paper studied the Helium content data collected in three natural springs of the Caucasus during seven years. A very similar result, that is the simultaneous appearance of clear premonitory anomalies only on the occasion of a strong (<i>M</i>=7.0) but shallow (2–4km) earthquake, was obtained. The correspondence with the case of the Caucasus validates the interpretation of the Kamchatkian anomalies as precursors

Труднолечимый ревматоидный артрит. Какой он?

The widespread introduction into clinical practice of modern approaches to the treatment of rheumatoid arthritis (RA), the rational use of traditional and targeted antirheumatic drugs can effectively suppress inflammatory activity, restrain the progression of the disease and improve the quality of life of patients. At the same time, in some patients, even after the repeated change of targeted drugs, it is not possible to achieve the target level of RA activity. Serious difficulties arising in the management of such patients raised the question of identifying a special variant of the disease – difficult-to-treat (D2T) RA. The presence of various variants of D2T RA and the need to use a personalized approach to therapy justify the creation of special recommendations for the management of this category of patients. The first step in preparing these recommendations was the definition of D2T RA recently presented by the EULAR working group. It includes three criteria: 1) insufficient effectiveness of the therapy; 2) the presence of an active symptomatic disease; 3) clinical perception.Широкое внедрение в клиническую практику современных подходов к лечению ревматоидного артрита (РА), рациональное использование традиционных и таргетных противоревматических препаратов позволяют эффективно подавлять воспалительную активность, сдерживать прогрессирование болезни и улучшать качество жизни больных. Вместе с тем у части пациентов даже после повторной смены таргетных препаратов не удается добиться целевого уровня активности РА. Серьезные затруднения, возникающие при ведении таких пациентов, поставили вопрос о выделении особого варианта болезни – труднолечимого (difficult to treat, D2T) РА. Наличие разнообразных вариантов D2T РА и необходимость использования персонифицированного подхода к терапии обосновывают создание специальных рекомендаций по ведению данной категории больных. Первым шагом к подготовке данных рекомендаций стало определение понятия D2T РА, недавно представленное рабочей группой EULAR. Оно предусматривает соответствие пациента трем критериям: 1) недостаточная эффективность проводимой терапии; 2) наличие активного симптоматического заболевания; 3) клиническое восприятие