K-Ar, δ18O and REE constraints on the genesis of ammonium illite from the Harghita Bãi hydrothermal system, Romania

Clay Minerals ◽  
2010 ◽  
Vol 45 (3) ◽  
pp. 393-411 ◽  
Author(s):  
N. Clauer ◽  
N. Liewig ◽  
I. Bobos

AbstractAmmonium illite and ammonium illite-smectite mixed layers, together with potassium illite, smectite and minute amounts of kaolinite were identified in hydrothermally altered andesite rocks from the Harghita Bãi area of the Eastern Carpathians, Romania. K-Ar dating and oxygen isotope tracing, as well as rare-earth elemental analyses were made to provide new information on the timing and crystal-chemical processes characterizing the crystallization and further evolution of these illite-type mineral phases.The combined results suggest the occurrence of hydrothermal activity in two distinct episodes with nucleation of two generations of illite-type particles of different chemistry and morphology. About 9.5 Ma ago, potassium illite crystallized in alteration halos of the porphyry Cu system, probably at a temperature of ~270ºC from fluids having a δ18O of ~2.9% (V-SMOW). Associated smectite seems to have precipitated slightly later in external alteration halos at a similar temperature, but from fluids depleted in alkalis and with a different δ18O. Alternately, ammonium-rich illite-smectite mixed layers formed very recently, less than ~1 million years ago at a temperature of ~90ºC from fluids of probable meteoric origin that altered the previously crystallized potassium illite, resulting in the crystallization of a new generation of ammonium illite-smectite mixed layers. Evidence of this dissolution-precipitation process is provided by a significant increase in the δ18O of the mixed-layer structures and by a significant change in their REE contents and distribution patterns. Occurrence of potassium in the ammonium-rich mixed layers probably relates to the progressive alteration of the first-generation potassium illite and a discrete concomitant take up of released K by the new NH4-rich interlayers of the ammonium mixed layered sequence.

2019 ◽  
Vol 2 (1) ◽  
pp. 22-33
Author(s):  
Bhadra Badam

Second generation of women of Baram Community is highly constructive in social norms, values, customs, and tradition and very sensitive in gender equality than first generation. The major issue of this study is to find out the gender roles of Baram community from a major festival - Chandipurnima. The nature of gender roles and changing pattern on festival between two generations among Baram community, sharing behavior during the festival, power relation between male and female has been addressed. There are vast differences on two generations regarding the gender roles, first generation is still traditional and believe on radical cultural practices where as new generation has the impact of modernity and change due to the education and labor migration. However new generation is found high alert in social identity and cultural practices of the community. As it is an ethnography the study has been conducted based on participant observation and interview on the special occasion of celebration of Chandipurnima of Baram Community of Gorkha.


2019 ◽  
Author(s):  
Zac Wylde ◽  
Foteini Spagopoulou ◽  
Amy K Hooper ◽  
Alexei A Maklakov ◽  
Russell Bonduriansky

Individuals within populations vary enormously in mortality risk and longevity, but the causes of this variation remain poorly understood. A potentially important and phylogenetically widespread source of such variation is maternal age at breeding, which typically has negative effects on offspring longevity. Here, we show that paternal age can affect offspring longevity as strongly as maternal age does, and that breeding age effects can interact over two generations in both matrilines and patrilines. We manipulated maternal and paternal ages at breeding over two generations in the neriid fly Telostylinus angusticollis. To determine whether breeding age effects can be modulated by the environment, we also manipulated larval diet and male competitive environment in the first generation. We found separate and interactive effects of parental and grandparental ages at breeding on descendants’ mortality rate and lifespan in both matrilines and patrilines. These breeding age effects were not modulated by grandparental larval diet quality or competitive environment. Our findings suggest that variation in maternal and paternal ages at breeding could contribute substantially to intra-population variation in mortality and longevity.


2020 ◽  
Author(s):  
Lungwani Muungo

The purpose of this review is to evaluate progress inmolecular epidemiology over the past 24 years in canceretiology and prevention to draw lessons for futureresearch incorporating the new generation of biomarkers.Molecular epidemiology was introduced inthe study of cancer in the early 1980s, with theexpectation that it would help overcome some majorlimitations of epidemiology and facilitate cancerprevention. The expectation was that biomarkerswould improve exposure assessment, document earlychanges preceding disease, and identify subgroupsin the population with greater susceptibility to cancer,thereby increasing the ability of epidemiologic studiesto identify causes and elucidate mechanisms incarcinogenesis. The first generation of biomarkers hasindeed contributed to our understanding of riskandsusceptibility related largely to genotoxic carcinogens.Consequently, interventions and policy changes havebeen mounted to reduce riskfrom several importantenvironmental carcinogens. Several new and promisingbiomarkers are now becoming available for epidemiologicstudies, thanks to the development of highthroughputtechnologies and theoretical advances inbiology. These include toxicogenomics, alterations ingene methylation and gene expression, proteomics, andmetabonomics, which allow large-scale studies, includingdiscovery-oriented as well as hypothesis-testinginvestigations. However, most of these newer biomarkershave not been adequately validated, and theirrole in the causal paradigm is not clear. There is a needfor their systematic validation using principles andcriteria established over the past several decades inmolecular cancer epidemiology.


2020 ◽  
Vol 54 (s41) ◽  
pp. 89-115
Author(s):  
Einat Gonen

Abstract This paper presents a diachronic study of Modern Hebrew agreement between numerals and their quantified nouns. This research is possible thanks to the discovery of two rare collections of recordings from the 1950s and 1960s, which document four generations of speakers and have become important sources of spoken Early Modern Hebrew. On the basis of these two corpora, I compare numeral agreement in the first two generations of speakers with present-day usage and analyze trends of change and conversation in Modern Hebrew. The study shows that the first generation of speakers (“Gen1”) largely acquired the gender distinction of cardinals. However, in contrast to other agreement issues that educated Gen1 speakers realized fully, numeral use showed variation and absence of agreement in a small set of cases. Moreover, some linguistic features of Gen1 Hebrew found in this study no longer characterize Present-Day Hebrew; among these features is prosodic conditioning, which led to a Gen1 tendency to use the feminine form of the numeral ‘four’ with masculine nouns more frequently than was the case with other numerals.


1986 ◽  
Vol 118 (4) ◽  
pp. 351-359 ◽  
Author(s):  
M.T. AliNiazee

AbstractSeasonal history, adult flight activity, and damage of the obliquebanded leafroller, Choristoneura rosaceana (Harris), on filbert were studied during a 7-year period between 1976 and 1984. Data from periodic field counts and moth catches in sex-attractant traps indicated two generations per year. The first-generation adult capture peak was generally higher than the second, except in 1978 when about an equal number of moths were trapped from both generations. A physiological time scale, using degree-days (DD), was devised for predicting emergence of obliquebanded leafroller adults. The first adults from overwintering larvae emerged at approximately 374 DD above a threshold of 10 °C starting 1 March. A total of 1172 DD were required between the first and the last adult emergence during the first generation and about 519 DD during the second generation. The obliquebanded leafroller causes both foliar and nut damage in filbert orchards of Oregon. Foliar damage was insignificant, but nut damage, caused exclusively by the first-generation larvae during June and early July, was highly destructive. Larval feeding on nuts caused staining and premature drop of infested nuts resulting in substantial yield reduction in heavily infested orchards.


1993 ◽  
Vol 265 (6) ◽  
pp. L521-L548 ◽  
Author(s):  
R. P. Bolender ◽  
D. M. Hyde ◽  
R. T. Dehoff

Today all structural information of the lung can be quantified and interpreted in the three-dimensional space of real-world biology. Remarkable achievements in the theory and practice of biological stereology are creating a new generation of data suitable for constructing structural hierarchies. Such hierarchies serve to organize and link biological data, thereby providing a framework on which to build new information systems. In this review, we describe the new tools of quantitative morphology and show how they can be used to design new experiments for lung research.


2013 ◽  
Vol 47 (1) ◽  
pp. 438 ◽  
Author(s):  
I. Thabet ◽  
A. Kilias ◽  
A. Koroneos ◽  
S. Kamh

The study deals with the petrography of the granitoid rocks intruding the five (A to E) domes of Hafafit Culmination. The morphological characteristics of zircon crystals are also examined, in order to elucidate the genesis of zircon and their host Hafafit granitoids. The granitoid rocks are tonalites, granodiorites and quartz diorites, all exhibiting gneissic texture. The zircon crystals from all the rock types intruding each one of the domes are examined in detail for colour, inclusions, crystal length, crystal width, elongation ratio, crystal form and habit, degree of roundness and corrosion, and are distinguished in groups on the basis of the previous characteristics. Two generations of zircons have been recognized; the first generation with magmatic features and the second one with post magmatic features. The first generation of zircon is attributed to the subduction, magmatic and deformation events while the second generation of zircon is attributed to metamorphism.


2021 ◽  
Vol 29 ◽  
pp. 41-46
Author(s):  
V. A. Katsan ◽  
A.I. Potopalsky ◽  
B.O. Zadorozhnii

Aim. The investigation of the influence of the constituents of Izatison, DMSO and PEG400, on the oat growth and its grain productivity during 2 generations after the seed treatment became the aim of this study for the elucidation of mechanism of Izatison stimulant influence. Methods. The broad scale of the concentrations of the solvents composition in the proportion, to be as in Izatison, was used. The plants were grown in the field. The growth processes were evaluated by the stem height on the tubing stage. The grain productivity was characterized by the panicle length, the grains number in the panicle and of theirs weight. Results. The dependence of influence of the solvents composition on the stem growth from its concentration was detected in the first generation. In some variants the negative influence was revealed on the grains number in the panicle and on theirs weight. The stimulation of the growth regardless from the solvents concentration was observed in the second generation and the more pronounced negative effect on the grain productivity. Conclusions. The solvents DMSO and PEG400 are able to influence on the oat growth and its productivity, and that effect was manifested also in 2 generation after the seed treatment. Keywords: Izatison, DMSO, PEG400, oat growth and grain productivity.


2017 ◽  
Vol 9 (4) ◽  
pp. 1994-2003
Author(s):  
Hemant Sharma ◽  
Maha Singh Jaglan ◽  
S. S. Yadav

Biology of pink stem borer, Sesamia inferens (Walker) (Lepidoptera: Noctuidae) was conducted during 2015-16 in laboratories of CCS Haryana Agricultural University, Regional Research Station, Karnal on HQPM 1 (hybrid) and HKI 1128 (inbred) for two generations at room temperature. Results on biology of S. inferens in the first generation revealed that incubation period varied from 10-14 days on HQPM 1 and 11-15 days on HKI 1128. The larval duration lasted for 21-37 days on HQPM 1 and 24-39 days on HKI 1128. The adult longevity of male and female ranged from 6-7 days and 7-8 days on HQPM 1 and 5-7 days and 6-7 days on HKI 1128, respectively. The total life span ranged from 63-72 days for female and 45-58 days for male on HQPM 1 and 65-74 days for female and 49-62 days for male on HKI 1128, respectively in the first generation. The total life span in second generation ranged 94-107 days for female and 83-96 days for male on HQPM 1 and 98-112 days for female and 86-101 days for male on HKI 1128. The biology of an insect pest is a condition precedent to find out its management strategies. The biology of S. inferens on maize has not yet been studied in north western part of the country. Having regards to the fact that no systematic work on this aspect has been carried out, studies were conducted on biology of this pest for developing efficient pest management strategies.


2012 ◽  
Vol 23 (2) ◽  
pp. 65-76
Author(s):  
Willi Goetschel

This paper examines Rosenzweig?s philosophic project in the context of his time as a critical intervention in the discussion of the place of Jewish thought in the university and in society. If Hermann Cohen represented the first generation of Jewish philosophers claiming that participation in the university is constitutive for the institution?s claim to universalism, the second generation-represented by Martin Buber - was more diffident about the university and its openness. For Buber, literary modernism offered what the university would refuse. Disappointed about the failure of the recognition of the efforts of the previous two generations, Rosenzweig represents the third generation. He turns the situation into a creative response anchoring philosophy as a project that calls for a resolute move outside the university.


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