The Lake Mungo geomagnetic excursion

1976 ◽  
Vol 281 (1305) ◽  
pp. 515-542 ◽  
Keyword(s):  
Field Strength ◽  
Geomagnetic Excursion ◽  
Southeastern Australia ◽  
Low Field ◽  
The World ◽  
Very High ◽  
Geomagnetic Field Strength ◽  
Different Parts ◽  
Field Strengths

Archaeomagnetic studies have been made of prehistoric aboriginal fireplaces occurring along the ancient shore of Lake Mungo, a dried out lake in southeastern Australia. Directions of magnetization preserved in ovenstones and baked hearths show that wide departures of up to 120° from the axial dipole field direction occurred about 30000 years ago. The determination of the variation in geomagnetic field strength from the baked material is complicated by non-ideal behaviour during Thellier’s double heating method. The problem appears to arise from the subsequent (postfiring) formation of iron oxyhydroxides during a period in which the water level in the lake rose. During laboratory heatings these oxyhydroxides dehydrate causing the non-ideal behaviour observed. The ancient field strengths deduced are therefore probably minimum values. The geomagnetic excursion recorded between at least 30780 ±520 and 28140 ±370 years b.p. on the conventional radiocarbon time scale is associated with very high field strengths between 1 and 2 Oe (1 Oe » 79.6 A m_ 1 ). The field strength subsequently decreased to between 0.2 and 0.3 Oe after the excursion. This main excursion is referred to as the Lake Mungo geomagnetic excursion. There is evidence that a second excursion associated with low field strengths of 0.1-0.2 Oe occurred around 26000 years b.p. A review of geomagnetic excursions less than 40 000 years in age shows that it may be premature to assume that these are world-wide synchronous features. The range of ages and their groupings in different parts of the world may indicate they are temporary non-dipole features of continental extent. However, the duration of most excursions (order of 103 years) is very similar to that of polarity transitions and this could indicate they are aborted reversals.

scholarly journals Using RESOURCESAT-1 data for determination of snow cover and snowline altitude, Baspa Basin, India

2010 ◽  
Vol 51 (54) ◽  
pp. 9-13 ◽  
Author(s):  
Rakesh Kaur ◽  
Anil V. Kulkarni ◽  
B.S. Chaudhary
Keyword(s):  
Snow Cover ◽  
Meteorological Data ◽  
Sensor Data ◽  
Wide Field ◽  
The World ◽  
Field Sensor ◽  
Terrain Elevation ◽  
Very High ◽  
Wide Swath

AbstractThis paper presents a method for deriving the snowline altitude using a combined analysis of terrain elevation and multispectral Advanced Wide Field Sensor (AWiFS) data from the RESOURCESAT-1 satellite, launched by India on 17 October 2003. AWiFS is a unique instrument capable of acquiring imagery of the world repeatedly every 5 days with very high radiometric resolution. It provides a wide swath width, which is very useful for snow-cover mapping. Snowline altitude is a good indicator of snow coverage. Snowline altitude for the period from October 2004 to June 2005, and from October 2006 to June 2007, is determined for the Baspa Basin, which is located in the Kinnaur district of Himachal Pradesh, India. It is observed that snowline altitude is generally higher during the year 2006/07 than during 2004/05, except in December 2006 and March 2007. The results obtained with the analysis presented here are validated using available meteorological data and are found to be satisfactory. This thus establishes a method that can be applied to other terrains and over longer periods of time within the coverage of the AWiFS sensor data.

scholarly journals On the Validity of the Two-term Approximation of the Electron Distribution Function

1971 ◽  
Vol 24 (4) ◽  
pp. 835 ◽  
Author(s):  
RE Robson ◽  
Kailash Kumar
Keyword(s):  
Distribution Function ◽  
Field Strength ◽  
Drift Velocity ◽  
Electron Distribution ◽  
Electron Distribution Function ◽  
Polynomial Expansion ◽  
Neutral Gas ◽  
Low Field ◽  
Term Approximation ◽  
Field Strengths

The Boltzmann equation for electrons moving in a neutral gas under the influence of an externally applied field is solved by expanding the electron distribution function in terms of Legendre and Sonine polynomials. The solution is given in terms of infinite matrices which have elements ordered by the Sonine polynomial index, and which are dependent upon the field strength. From the structure of the formulae, it is possible to infer that truncation of the Legendre polynomial expansion after two terms is a good approximation at all field strengths. This is supported by calculations of the electron drift velocity at low field strengths, which show that the error introduced by making the two-term approximation is small, even when the deviation from equilibrium is significant. The convergence of the Sonine polynomial expansion is shown to be strongly depende:r;J.t upon field strength, and large matrices are required in the drift velocity formula at even small field strengths.

The Foundation and Early Development of the Nautical Almanac

1965 ◽  
Vol 18 (4) ◽  
pp. 391-401 ◽  
Author(s):  
Eric G. Forbes
Keyword(s):  
Eighteenth Century ◽  
Present Article ◽  
Early Development ◽  
Accurate Determination ◽  
Practical Possibility ◽  
The World ◽  
Nevil Maskelyne ◽  
Nautical Almanac ◽  
Different Parts

Soon after the middle of the eighteenth century, improvements in the design and construction of astronomical and nautical instruments, coupled with the increased accuracy of tables of the Moon's motion, at last made the accurate determination of longitude at sea by lunar distance a practical possibility. The Astronomer Royal, Nevil Maskelyne, was quick to appreciate the importance of publishing the calculated solar and lunar ephemerides, together with other relevant tables and explanations, in the form of a Nautical Almanac, which was first printed under his supervision in 1766 and immediately distributed to mariners in different parts of the world. The present article is concerned with the circumstances relating to the origin and development of this publication during the first fifty years of its existence.

scholarly journals Effect of Mineral Composition on Transverse Relaxation Time Distributions and MR Imaging of Tight Rocks from Offshore Ireland

Minerals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 232
Author(s):  
Stian Almenningen ◽  
Srikumar Roy ◽  
Arif Hussain ◽  
John Georg Seland ◽  
Geir Ersland
Keyword(s):  
Magnetic Field ◽  
Relaxation Time ◽  
Mr Imaging ◽  
Field Strength ◽  
High Field ◽  
Transverse Relaxation Time ◽  
Transverse Relaxation ◽  
The Core ◽  
Low Field ◽  
Field Strengths

In this paper, we investigate the effect of magnetic field strength on the transverse relaxation time constant (T2) in six distinct core plugs from four different rock types (three sandstones, one basalt, one volcanic tuff and one siltstone), retrieved from offshore Ireland. The CPMG pulse-sequence was used at two different magnetic field strengths: high-field at 4.70 T and low-field at 0.28 T. Axial images of the core plugs were also acquired with the RAREst sequence at high magnetic field strength. Thin-sections of the core plugs were prepared for optical imaging and SEM analysis, and provided qualitative information on the porosity and quantification of the elemental composition of the rock material. The content of iron varied from 4 wt. % to close to zero in the rock samples. Nevertheless, the effective T2 distributions obtained at low-field were used to successfully predict the porosity of the core plugs. Severe signal attenuations from internal magnetic gradients resulted in an underestimation of the porosity at high-field. No definitive trend was identified on the evolution of discrete relaxation time components between magnetic field strengths. The low-field measurements demonstrate that NMR is a powerful quantitative tool for petrophysical rock analysis as compared to thin-section analysis. The results of this study are of interest to the research community who characterizes natural gas hydrates in tight heterogeneous core plugs, and who typically relies on MR imaging to distinguish between solid hydrates and fluid phases. It further exemplifies the importance of selecting appropriate magnetic field strengths when employing NMR/MRI for porosity calculation in tight rock.

scholarly journals Ukrainian paroemias with somatic components

2020 ◽  
Vol 13 (22) ◽  
pp. 113-121
Author(s):  
Nataliia Vorona ◽  
◽  
Nataliia Pilipenko-Fritsak ◽  
Keyword(s):  
Moral Values ◽  
The Body ◽  
Human Consciousness ◽  
Semantic Meaning ◽  
Language And Culture ◽  
World Outlook ◽  
The World ◽  
Illustrative Material ◽  
Different Parts

The paper is devoted to the analysis of Ukrainian paroemias with somatic components, determination of their quantitative ratio, and semantic meaning of the most common representative ones. Paroemias in the present study mean proverbs and sayings, that help to understand the linguistic picture of the world, a person's place in this world, the paradigm of his/her ideas about himself/herself, the environment, moral values, and so on. The close connection of somatics with everything that surrounds a person, contributes to the symbolization of the functions of different parts of the body, plays an important role in modeling the somatic fragment of the linguistic picture of the world. The conditionality of the consideration of somatisms is explained by the fact that they perfectly represent the anthropocentric worldview, and paroemias with somatic components allow to combine anthropocentrism with nationcentrism. The paper analyzes the research published during the last 5 years, which deals with various aspects of this issue and concludes that there is a lack of thorough research with a comprehensive consideration of somatic phraseological units, especially Ukrainian. The aim of the research is to reveal the meanings inherent to Ukrainian somatic paroemias, ways to reproduce the thinking and mentality of the Ukrainian people, to identify the place of paroemias with somatisms among the great variety of Ukrainian proverbs and sayings. The object of the study is 720 paroemias from the collection «The best proverbs and sayings of the Ukrainians», compiled by O. A. Popova. The paper contains a large number of examples and illustrative material. The description and analysis of paroemias with somatic components enable to determine what percentage of Ukrainian paroemias are somatic components and which of these elements are primary or secondary ones, and values they correspond to. The study presents figures and information illustrating and confirming the main aspects of the article. The analysis of a large number of paroemias with somatic components such as head, arm, eye, mouth, leg, heart, and ear showed that the most representative somatic components of Ukrainian paroemias are head, arms, and eyes. The authors conclude that Ukrainian paroemias with somatic components are an example of combining the universal in each culture with a specific ethnonational. The widespread use of somatisms in the Ukrainian paroemias is explained by the nature of human development of the world around us and by the principles of anthropocentrism and anthropomorphism of the world perception in human consciousness. Further study of the Ukrainian paroemias with somatic components will enrich our knowledge of the interaction of language and culture of the Ukrainians, will contribute to the further study of the world outlook of the Ukrainian nation.

scholarly journals MUHAMMAD HASHIM THATTWI AND HIS EDUCATIONAL EFFORTS: محمد هاشم التتوي وجهوده العلمية: دراسة تحليلية وصفية

2019 ◽  
Vol 2 (7) ◽  
Author(s):  
KHALIL AHMED SALIH, SARDAR AHMED YAQOOB, SUMYYAH SARDAR AHME
Keyword(s):  
Mother Tongue ◽  
Arabic Language ◽  
Foreign Countries ◽  
Sindh Province ◽  
The World ◽  
Very High ◽  
Different Parts

This article of mine has been written on such personality who is famous and his educational efforts are featured in different educational fields. This personality with all his pelvis and interest has worked in ballad, compilation, fatwa, Fiqah and literature. Above all, he also got across languages other than his mother tongue. Even he got across Arabic language as well. And though he is not that much famous in Arabic countries but his personality is discussed in all academic circles in Pakistan especially in the Sindh province. This is the reason I have chosen this personality for this article so that I can highlight his research overview from different aspects. Here this is also noteworthy that in this article I have debated upon his personality, and in this case I have mentioned details and statements about him, and the services he did are also discussed in detail with complete explanation under research title. And the teachers from whom he got education whether they belong to Pakistan or foreign countries, their brief introduction is also discussed. This article of mine contains one trial, seven topics and an end. And in the end of the article, important results are also registered. And this personality Muhammad Hashim Thattwi travelled different parts of the world in order to get education which I have mentioned in this article. And his position was very high in all the academic circles. The evidence of his highness is that his colleagues and other scholars have appreciated his work. This is the clear evidence that Muhammad Hashim Thattwi was delusional scientific character. And in the end of the article I have mentioned his date of death and the place where he is buried.

Behavior of Extra Electrons in the Liquids Methane, Ethane, and Propane

1971 ◽  
Vol 49 (6) ◽  
pp. 984-985 ◽  
Author(s):  
M. G. Robinson ◽  
P. G. Fuochi ◽  
G. R. Freeman
Keyword(s):  
Field Strength ◽  
Ion Pairs ◽  
Liquid Argon ◽  
Low Field ◽  
Electrical Conductances ◽  
Radiation Induced ◽  
Liquid Methane ◽  
Field Strengths

The radiation induced electrical conductances of liquids methane, ethane, and propane have been measured. At a field strength of 5 kV/cm the number of ion pairs collected at the electrodes per 100 eV absorbed by the liquid was 1.5 in methane (−160°), 0.20 in ethane (−90°), and 0.14 in propane (−90°). The short-lived conductance transient (k/u overshoot) observed at low field strengths in methane was 40% as large as that in argon. No transient was observable in ethane or propane. The freeness of motion of electrons in liquid methane is nearly as great as that in liquid argon and much greater than that in ethane or propane.

BIOASSAY CHARACTERISTICS OF INDIVIDUAL URINARY GONADOTROPHIN EXTRACTS

1963 ◽  
Vol 42 (2) ◽  
pp. 214-224
Author(s):  
Raymond C. Mellinger ◽  
Jalileh A. Mansour ◽  
Richmond W. Smith
Keyword(s):  
Reference Material ◽  
Young Women ◽  
Reference Standard ◽  
General Acceptance ◽  
Modifying Factors ◽  
Large Numbers ◽  
The World ◽  
Quantitative Bioassay ◽  
Different Parts ◽  
Age And Sex

ABSTRACT A reference standard is widely sought for use in the quantitative bioassay of pituitary gonadotrophin recovered from urine. The biologic similarity of pooled urinary extracts obtained from large numbers of subjects, utilizing groups of different age and sex, preparing and assaying the materials by varying techniques in different parts of the world, has lead to a general acceptance of such preparations as international gonadotrophin reference standards. In the present study, however, the extract of pooled urine from a small number of young women is shown to produce a significantly different bioassay response from that of the reference materials. Gonadotrophins of individual subjects likewise varied from the multiple subject standards in many instances. The cause of these differences is thought to be due to the modifying influence of non-hormonal substances extracted from urine with the gonadotrophin and not necessarily to variations in the gonadotrophins themselves. Such modifying factors might have similar effects in a comparative assay of pooled extracts contributed by many subjects, but produce significant variations when material from individual subjects is compared. It is concluded that the expression of potency of a gonadotrophic extract in terms of pooled reference material to which it is not essentially similar may diminish rather than enhance the validity of the assay.

Christianity in the Twentieth Century

2019 ◽  
Author(s):  
Brian Stanley
Keyword(s):  
Latin America ◽  
Racial Identity ◽  
Sub Saharan Africa ◽  
Central Importance ◽  
Regional Survey ◽  
History Of Christianity ◽  
The World ◽  
History Of ◽  
Sub Saharan ◽  
Different Parts

This book charts the transformation of one of the world's great religions during an age marked by world wars, genocide, nationalism, decolonization, and powerful ideological currents, many of them hostile to Christianity. The book traces how Christianity evolved from a religion defined by the culture and politics of Europe to the expanding polycentric and multicultural faith it is today—one whose growing popular support is strongest in sub-Saharan Africa, Latin America, China, and other parts of Asia. The book sheds critical light on themes of central importance for understanding the global contours of modern Christianity, illustrating each one with contrasting case studies, usually taken from different parts of the world. Unlike other books on world Christianity, this one is not a regional survey or chronological narrative, nor does it focus on theology or ecclesiastical institutions. The book provides a history of Christianity as a popular faith experienced and lived by its adherents, telling a compelling and multifaceted story of Christendom's fortunes in Europe, North America, and across the rest of the globe. It demonstrates how Christianity has had less to fear from the onslaughts of secularism than from the readiness of Christians themselves to accommodate their faith to ideologies that privilege racial identity or radical individualism.

THE 2019 NOVEL PANDEMIC OF CORONAVIRUS DISEASE (COVID-19): A STUDY OF EXISTING EVIDENCE IN THE INDIAN POPULATION

2020 ◽  
Vol 7 (2) ◽  
pp. 199-204
Author(s):  
Shrikant Verma ◽  
Mohammad Abbas ◽  
Sushma Verma ◽  
Syed Tasleem Raza ◽  
Farzana Mahdi
Keyword(s):  
Disease Transmission ◽  
Indian Population ◽  
Respiratory Infections ◽  
Clinical Signs ◽  
Case Fatality ◽  
Public Health Emergency ◽  
The World ◽  
And Control ◽  
General Wellbeing ◽  
Different Parts

A novel spillover coronavirus (nCoV), with its epicenter in Wuhan, China's People's Republic, has emerged as an international public health emergency. This began as an outbreak in December 2019, and till November eighth, 2020, there have been 8.5 million affirmed instances of novel Covid disease2019 (COVID-19) in India, with 1,26,611 deaths, resulting in an overall case fatality rate of 1.48 percent. Coronavirus clinical signs are fundamentally the same as those of other respiratory infections. In different parts of the world, the quantity of research center affirmed cases and related passings are rising consistently. The COVID- 19 is an arising pandemic-responsible viral infection. Coronavirus has influenced huge parts of the total populace, which has prompted a global general wellbeing crisis, setting all health associations on high attentive. This review sums up the overall landmass, virology, pathogenesis, the study of disease transmission, clinical introduction, determination, treatment, and control of COVID-19 with the reference to India.

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