Dynamical evolution of interplanetary magnetic fields and flows between 0.3 AU and 8.5 AU: Entrainment

The radial evolution of interplanetary flows and associated magnetic fields between 0.3 AU and 8.5 was analyzed using data from Helios 1 and Voyager 1, respectively. During a 70 day interval Voyager 1 observed two streams which appeared to be recurrent and which had little fine structure. The corresponding flows observed by Helios 1 were much more complex, showing numerous small streams, transient flows and shocks as well as a few large corotating streams. It is suggested that in moving to 8 AU the largest corotating streams swept up the slower flows (transient and/or corotating streams) and shocks into a relatively thin region in which they coalesced to form a single large amplitude compression wave. This combined process of sweeping and coalescence is referred to as entrainment. The resulting large amplitude compression wave is different from that formed by the steepening of a corotating stream from a coronal hole, because different flows from distinct sources, with possibly different composition and magnetic polarity, are brought together to form a single new structure

Associations between coronal mass ejections and interplanetary shocks

Nearly continuous complementary coronal observations and interplanetary plasma measurements for the years 1979-1982 are compared. It is shown that almost all low latitude high speed coronal mass ejections (CME's) were associated with shocks at HELIOS 1. Some suitably directed low speed CME's were clearly associated with shocks while others may have been associated with disturbed plasma (such as NCDE's) without shocks. A few opposite hemisphere CME's associated with great flares seem to be associated with shocks at HELIOS

Magnetic fields and flows between 1 AU and 0.3 AU during the primary mission of HELIOS 1

The recurrent flow and field patterns observed by HELIOS 1, and the relation between these patterns and coronal holes are discussed. Four types of recurrent patterns were observed: a large recurrent stream, a recurrent slow (quiet) flow, a rapidly evolving flow, and a recurrent compound stream. There recurrent streams were not stationary, for although the sources recurred at approximately the same longitudes on successive rotations, the shapes and latitudinal patterns changed from one rotation to the next. A type of magnetic field and plasma structure characterized by a low ion temperature and a high magnetic field intensity is described as well as the structures of stream boundaries between the sun at approximately 0.3 AU

Interpretation of the ion mass spectra in the mass range 25-35 obtained in the inner coma of Halley's comet by the HIS-sensor of the Giotto IMS Experiment

The IMS-HIS double-focussing mass spectrometer that flew on the Giotto spacecraft covered the mass per charge range from 12 to 56 (AMU/e). By comparing flight data, calibration data, and results of model calculations of the ion population in the inner coma, the absolute mass scale is established, and ions in the mass range 25 to 35 are identified. Ions resulting from protonation of molecules with high proton affinity are relatively abundant, enabling us to estimate relative source strengths for H2CO, CH3OH, HCN, and H2S, providing for the first time a positive in situ measurement of methanol. Also, upper limits for NO and some hydrocarbons are derived

Observations of plasma dynamics in the coma of P/Halley by the Giotto Ion Mass Spectrometer

Observations in the coma of P/Halley by the Giotto Ion Mass Spectrometer (IMS) are reported. The High Energy Range Spectrometer (HERS) of the IMS obtained measurements of protons and alpha particles from the far upstream region to the near ionopause region and of ions from mass 12 to 32 at distances of about 250,000 to 40,000 km from the nucleus. Plasma parameters from the High Intensity Spectrometer (HIS) of the IMS obtained between 150,000 to 5000 km from the nucleus are also discussed. The distribution functions of water group ions (water group will be used to refer to ions of 16 to 18 m/q, where m is in AMU and q is in unit charges) are observed to be spherically symmetric in velocity space, indicating strong pitch angle scattering. The discontinuity known as the magnetic pile-up boundary (MPB) is apparent only in proton, alpha, and magnetometer data, indicating that it is a tangential discontinuity of solar wind origin. HERS observations show no significant change in the properties of the heavy ions across the MPB. A comparison of the observations to an MHD model is made. The plasma flow directions at all distances greater than 30,000 km from the nucleus are in agreement with MHD calculations. However, despite the agreement in flow direction, within 200,000 km of the nucleus the magnitude of the velocity is lower than predicted by the MHD model and the density is much larger (a factor of 4). Within 30,000 km of the nucleus there are large theoretical differences between the MHD model flow calculations for the plane containing the magnetic field and for the plane perpendicular to the magnetic field. The observations agreed much better with the pattern calculated for the plane perpendicular to the magnetic field. The data obtained by the High Energy Range Spectrometer (HERS) of the IMS that are published herein were provided to the International Halley Watch archive

Beagle 2: Mission to Mars — current status

Beagle 2, developed in the UK, was launched on June 2, 2003. It landed on Mars on December 25th, 2003 in Isidis Planitia, a large sedimentary basin. To date, the team is awaiting signals from the Beagle 2 lander. Current status of the mission will be reported

Economic growth in the post-socialist Russian Federation after 1991 : the role of institutions

The paper emphasizes the transition in Russia and the role institutions played before and during the process. In Russia, a ?big bang? approach was applied. That is to say, transition was conducted all of a sudden, omitting important underlying reforms. This practice should function as a shock therapy. Hence, the approach should leave no other chance than an abrupt adaption to the new free-market rules. These rules would then lead to fast economic growth and development, as they did in other places. However, since Russian GDP per capita and thereby living standards deteriorated dramatically in the years after the collapse of the Soviet Union, the plan did not work. At any rate, since then Russian economic indicators recovered and partly achieved their pre-1991 levels at the end of the last decade. The paper depicts Russia?s reform efforts and the subsequent developments. The close ties among the political elite, the banking sector and the old nomenklatura are demonstrated. The patrimonial system that persisted for centuries is still observable at the state level. At any rate, Russia can neither evade its historical and institutional development path nor its societal structures that are based on networks and nepotism. Russia?s systemic lack of the rule of law and therewith of secure property, the character of the Russian political system with the patriarch as the head of state and the resulting necessity of corruption and bribes inhibit the realization of its full growth potential

МИРГОРОДСЬКИЙ ПОЛК В РОСІЙСЬКО-ТУРЕЦЬКІЙ ВІЙНІ 1735-1739 РР.

Тема пропонованої шановному читачеві статті знаходиться на перетині воєнної історії та краєзнавства. Після тривалої неуваги, зараз воєнна історія, зокрема козаччини, розробляється досить динамічно. Варто згадати хоча б роботи І.Стороженка [1], В.Заруби [2], О.Сокирка [3], Г.Шпитальова [4]. Одночасно все ще не розроблена докладно воєнна історія полків, які складали Гетьманщину. Хоча спроби такого роду є [5], але вони зосереджені не стільки на воєнній історії, скільки на історії полку загалом і, на жаль, не представлені у вигляді монографічних досліджень та не викладені в Інтернеті, що суттєво ускладнює доступ до результатів таких досліджень. Сюжет, пов’язаний із участю Миргородського полку в російсько-турецькій війні 1735-1739 років, не знайшов висвітлення в історіографії, хоча деякі факти містять дослідження А.Байова [6], О.Апанович [7] та вже згадувана монографія Г.Шпитальова. Протягом війни Миргородський полк брав участь як у далеких виправах, так і в ближніх походах різного роду – фортифікаційних, тривожних, для планової охорони кордонів. Залучення козаків Миргородського полку до далеких походів розпочалося вже у червні 1735 р., коли всі полки (крім Стародубського та Чернігівського) вирушили до фортеці Святого Іоанна на Українській лінії, де мали збиратися для виправи на Крим. До прибуття на лінію генерального осавула Ф.Лисенка обов’язки командира цього з’єднання виконував миргородський полковник Павло Апостол [8]. Кількість козаків Миргородського полку, які вирушили в цей похід, точно невідома. Проте є дані щодо старшини, яка очолила виправу – полковник П.Апостол, суддя Ф.Остроградський, писар В.Тихонович, осавул А.Волевач, хорунжі Т.Калницький та К.Шкурка [9]. Згідно з планами Генеральної військової канцелярії (далі – ГВК) передбачалося для Кримської (1736) виправи мобілізувати 16001 гетьманця, в тому числі 1196 шабель Миргородського полку [10]. Виникли певні проблеми з залученням старшини. Наприклад, миргородський обозний С.Родзянка уперто відмовлявся від походу під приводом хвороби, в яку полковник абсолютно не вірив. Проте С.Родзянка апелював до ГВК, де знайшов підтримку. Врешті, полкова старшина миргородців у цій виправі була представлена тими ж постатями, що й 1735 р., лише осавула А.Волевача замінив його колега С.Ґалаґан [11]. За попередніми планами на 1737 р. Миргородський полк мав виставити 849 шабель у Кримський похід. Після рішення фельдмаршала Мініха залишити слобідських козаків для охорони кордону їм на заміну залучили ще 200 миргородців [12]. На цьому зміни не закінчилися. На вимогу фельдмаршала Мініха Миргородський полк перейшов у його підпорядкування і вирушив замість Кримського в Очаківський похід

Molecular Genetics of T Cell Development

T cell development is guided by a complex set of transcription factors that act recursively, in different combinations, at each of the developmental choice points from T-lineage specification to peripheral T cell specialization. This review describes the modes of action of the major T-lineage-defining transcription factors and the signal pathways that activate them during intrathymic differentiation from pluripotent precursors. Roles of Notch and its effector RBPSuh (CSL), GATA-3, E2A/HEB and Id proteins, c-Myb, TCF-1, and members of the Runx, Ets, and Ikaros families are critical. Less known transcription factors that are newly recognized as being required for T cell development at particular checkpoints are also described. The transcriptional regulation of T cell development is contrasted with that of B cell development, in terms of their different degrees of overlap with the stem-cell program and the different roles of key transcription factors in gene regulatory networks leading to lineage commitment