Tropopause and hygropause variability over the equatorial Indian Ocean during February and March 1999.

Measurements of temperature, water vapor, total water, ozone, and cloud properties were made above the western equatorial Indian Ocean in February and March 1999. The cold-point tropopause was at a mean pressure-altitude of 17 km, equivalent to a potential temperature of 380 K, and had a mean temperature of 190 K. Total water mixing ratios at the hygropause varied between 1.4 and 4.1 ppmv. The mean saturation water vapor mixing ratio at the cold point was 3.0 ppmv. This does not accurately represent the mean of the measured total water mixing ratios because the air was unsaturated at the cold point for about 40% of the measurements. As well as unsaturation at the cold point, saturation was observed above the cold point on almost 30% of the profiles. In such profiles the air was saturated with respect to water ice but was free of clouds (i.e., backscatter ratio <2) at potential temperatures more than 5 K above the tropopause and hygropause. Individual profiles show a great deal of variability in the potential temperatures of the cold point and hygropause. We attribute this to short timescale and space-scale perturbations superimposed on the seasonal cycle. There is neither a clear and consistent “setting” of the tropopause and hygropause to the same altitude by dehydration processes nor a clear and consistent separation of tropopause and hygropause by the Brewer-Dobson circulation. Similarly, neither the tropopause nor the hygropause provides a location where conditions consistently approach those implied by a simple “tropopause freeze drying” or “stratospheric fountain” hypothesis

Nucleation of Flux Instabilities in Thin Super-Conducting Films : Nanosecond Magneto-Optical Investigations

We have investigated the short time dynamics flux distribution of thin YBa2Cu3O7-d films by means of time resolved magnetooptics. Local heating of the superconductor with a focussed laser pulse in a region with high shielding currents leads to an instability in the magnetic flux distribution on a nanosecond time scale. The instability develops in two steps giving rise to additional flux penetration and to a branching of the flux front into the superconductor. An estimate of the width of the branches based on Londons equations shows good agreement with the experiment

Nanosecond magneto-optic study of a new instability in thin YBa2Cu3O7-x films

We have investigated the dynamics of flux penetration into thin superconducting YBa2Cu307-x films using a magneto-optic technique with nanosecond time resolution. For films carrying large shielding currents an instability in the magnetic flux distribution is discovered, which can be triggered by a local perturbation, e.g., by a focused laser pulse. The instability develops in the form of fine ramified flux structures, with a propagation speed of the flux front on the order of 5 X 1O 4 m/s

Nucleation and growth of a flux instability in superconducting Y Ba2 Cu3 O7-x films

Using a high speed magneto-optic technique we have investigated the dynamics of a new flux instability in thin superconducting Y Ba2 Cu3 O7-x films exposed to an external magnetic field of several 10 -2 T. The instability was nucleated by a 5 ns laser pulse, which heated a small spot of the sample in a region of high shielding currents. Two subsequent regimes in the development of the instability are discovered, which give rise to strikingly different flux distributions. The formation of flux branches, which are characteristic for the second stage, occurs on a time scale of a hundred nanoseconds

Magnetic instability in HTSC films

We have investigated the short time dynamics in the magnetic flux distribution of thin YBa2Cu3O7-x films by means of time resolved magnetooptics. Local heating of the superconductor with a focussed laser pulse in a region with high shielding currents leads to an instability in the magnetic flux distribution. A pump probe technique allowed to visualize changes in the flux distribultion on a nanosecond time sale. The instability develops in two steps giving rise to additional flux penetration and to a branching of the flux front into the superconductor

Ponowna likwidacja starych odwiertów eksploatacyjnych : potencjalne źródła zanieczyszczenia środowiska w nieczynnych złożach węglowodorów w Republice Czeskiej

This article deals with a significant issue of environmental protection of oil and gas deposits that have recently drawn a considerable attention. The presence of old insufficiently sealed or entirely unsealed wells, formerly serving a purpose of oil and natural gas extraction, pose a significant threat to the environment. In the South Moravia region of the Czech Republic (an area of hydrocarbon extraction both in historical and recent times), there is a significant amount (hundreds) of production wells. It is very difficult or often even impossible to find information in archival materials on the cease of extraction from these wells and on the system of abandonment procedures applied. During the recent surveying and re-abandonment works, it was found that many wells had been abandoned inadequately and unprofessionally, and numbers of wells still have not been abandoned at all. This poses a considerable risk to the South Moravian landscape, especially to the sources of drinking water and to agriculture (to the Protected Area of Natural Water Accumulation - CHOPAV, Morava River Quaternary). Furthermore, it is a significant threat to the areas where extremely valuable biotopes occur. This article discusses the possible disposal of these ecological hazards to the areas of hydrocarbon deposit occurrences through recycling of old drawing wells as potential pollution sources of soil and water. Similar problems have certainly appeared in the Polish territory, where intense extraction took place at a far greater number of deposits, and where the wells already operated in the 19th century, in days gone by when there was little knowledge of abandonment procedures and little awareness of proper old well sealing.W artykule omówiono ważny problem ochrony środowiska w rejonie złóż ropy i gazu, którym ostatnio poświęcano wiele uwagi. Obecność starych, niedostatecznie uszczelnionych lub całkowicie nieuszczelnionych otworów wiertniczych, wcześniej wykorzystywanych do eksploatacji ropy i gazu ziemnego, jest poważnym zagrożeniem. W Czechach, na Południowych Morawach (obszar eksploatacji węglowodorów zarówno w przeszłości jak i obecnie), istnieje bardzo wiele (setki) otworów eksploatacyjnych. W materiałach archiwalnych bardzo trudno (często wręcz niemożliwe) jest znaleźć informacje na temat zarówno sposobu zakończenia eksploatacji w tych otworach, jak i zastosowanych procedur ich likwidacji. W trakcie niedawno prowadzonych badań i prac nad ponowną likwidacją otworów stwierdzono, że wiele z nich było zlikwidowanych nieodpowiednio i nieprofesjonalnie, a niektóre nadal nie zostały zlikwidowane. Stwarza to znaczne zagrożenie dla obszaru Południowych Moraw, w szczególności dla źródeł wody pitnej oraz rolnictwa (Obszar Chroniony Naturalnej Akumulacji Wód- CHOPAV, Czwartorzęd Rzeki Morawy). Co więcej, jest to poważne zagrożenie dla obszaru występowania bardzo cennych biotopów. Artykuł omawia możliwości usunięcia tych ekologicznych zagrożeń na obszarach złóż węglowodorów poprzez recykling dawnych otworów eksploatacyjnych będących źródłem zanieczyszczenia gleb i wód. Podobne problemy z pewnością pojawiają się na obszarze Polski, gdzie intensywnie eksploatowano znacznie więcej złóż, a otwory istniały już w XIX w., w okresie kiedy zarówno wiedza o procedurach likwidacji otworów wiertniczych, jak i świadomość znaczenia właściwego uszczelnienia starych otworów były niewielkie

НОВІ ІДЕЇ ОЦІНКИ ПОТЕНЦІАЛУ НЕТРАДИЦІЙНИХ ГАЗОВИХ РЕСУРСІВ У МИКУЛІВСЬКИХ ЮРСЬКИХ МЕРГЕЛЯХ У МОРАВСЬКІЙ ЧАСТИНІ ВІДЕНСЬКОГО БАСЕЙНУ (ЧЕСЬКА РЕСПУБЛІКА)

 The focus of this contribution is twofold: (1) analysis of tectonic patterns of the entire Vienna Basin and its subthrust level which includes autochthonous Jurassic sediments; (2) further geological and palynofacial characterization of Mikulov Upper Jurassic marls with ultimate aim to get new insights into unconventional prospects within the Moravian part of the Basin. The deposition here has been largely controlled by strike-slip reactivations within faults of the principal displacement zone. Liquid and gaseous hydrocarbons generated within the Mikulov source rock formation supplied several conventional oil and gas plays in the Miocene reservoirs mostly laterally but also vertically. Vertical migration of hydrocarbons took place via releasing jogs or “windows” appeared in thrust belt damage zone because of transtensional reactivations of en échelon arranged fragments of the principal displacement zone. Our model suggests presence of considerable unconventional gas resource play existing in deep overpressured Mikulov compartment sealed by impermeable combination of overlapping flysch and multiple the Carpathian thrust belt’s sheets. Ця публікація сфокусована на двох аспектах: 1) аналізі тектонічних особливостей Віденського басейну, в цілому, і його піднасувного комплексу, що включає автохтонні юрські відкладення; 2) подальшої геологічної та палінофаціальної характеристиці верньоюрських Микулівських мергелів. Кінцева мета досліджень - отримати нові знання про перспективи нетрадиційної вуглеводневої сировини в межах моравської частини басейну. Обстановки осадконагромадження тут значною мірою контролювалися зсувною активізацією окремих розривів у складі принципової дислокаційної зони. Рідкі й газоподібні вуглеводні, генеровані в нафтогазоматеринських Микулівських верствах, призвели до формування ряду традиційних родовищ нафти і газу в міоценових колекторах не тільки за рахунок переважної латеральної, а й вертикальної міграції. Вертикальна міграція відбувалася в умовах зсувної активізації принципової дислокаційної зони крізь періодично відкриті в непроникній зоні дроблення Карпатського насувного поясу «вікна» на ділянках локального розтягу у межах кулісоподібного вигину або зчленування зсувів. Наша модель передбачає наявність на глибоких горизонтах Микулівської формації значного скупчення нетрадиційного газу, який знаходиться в специфічних умовах аномально високого пластового тиску. 

Epac inhibits apoptosis of human leukocytes

cAMP is known to participate in the regulation of apoptosis in leukocytes. Depending on the cell type, pro- and antiapoptotic effects of cAMP have been described. Thus far, most of the cAMP-dependent effects have been attributed to the activation of PKA. However, Epac proteins (direct cAMP targets and guanine nucleotide exchange factors for Ras-like GTPases) have been shown recently to contribute to cAMP-dependent regulation of apoptosis. Therefore, we investigated the effects of the selective Epac activators 8-pCPT and Sp on apoptosis in human leukocytic cells (U937, HL-60, primary human mononuclear cells). We report here that Epac activation inhibits leukocyte apoptosis significantly. J. Leukoc. Biol. 86: 847-849; 2009