Generalized thin sheet approximation for magnetotelluric modelling.

Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Science.Microfiche copy available in Archives and Science.Vita.Bibliography: leaves 200-203.Ph.D

Prenatal Screening: A Tool to Predict, Prevent, and Prepare

There has been a considerable reduction in maternal mortality from 6 to 9/1000 live births and infant mortality from 100/1000 live births in the 1900s to less than 0.1/1000 live births and 7/1000 live births, respectively, in the 2000s. This is mostly due to nutritional improvement and obstetric and fetal medicine advancements. However, in the current era, prevention of mortality is not the only goal but also the prevention of morbidity. Thus comes the importance of prenatal screening, which would help us to predict and prevent maternal-fetal complications and in non-preventable conditions to prepare ourselves for optimal care of the mother and fetus. Prenatal screening is thus a test to detect potential health disorders in pregnant mothers or the fetus and to identify a subset who may need additional testing to determine the presence or absence of disease. It is done to categorize mothers into high-risk and low-risk pregnancies to prevent maternal complications, screen the fetus for aneuploidies, anomalies, and growth abnormalities, and decide on any indicated interventions and the time and mode of safe delivery so that an optimal perinatal outcome is achieved. Prenatal screening not only caters to identify fetal complications but also attempts to identify maternal complications early

Two novel hexadepsipeptides with several modified amino acid residues isolated from the fungus isaria

Two new cyclohexadepsipeptides have been isolated from the fungus Isaria. Fungal growth in solid media yielded hyphal strands from which peptide fractions were readily isolable by organic-solvent extraction. Two novel cyclodepsipeptides, isaridin A and isaridin B, have been isolated by reverse-phase HPLC, and characterized by ESI-MS and 1H-NMR. Single crystals of both peptides have been obtained, and their 3D structures were elucidated by X-ray diffraction. The isaridins contain several unusual amino acid residues. The sequences are cyclo(β-Gly-HyLeu-Pro-Phe-NMeVal-NMePhe) and cyclo(β-Gly-HyLeu-β-MePro-Phe-NMeVal-NMePhe), where NMeVal is N-methylvaline, NMePhe N-methylphenylalanine, and HyLeu hydroxyleucine (=2-hydroxy-4-methylpentanoic acid). The two peptides differ from one another at residue 3, isaridin A having an (S)-proline at this position, while β-methyl-(S)-proline (=(2S,3S)-2,3,4,5-tetrahydro-3-methyl-1H-pyrrole-2-carboxylic acid) is found in isaridin B. The solid-state conformations of both cyclic depsipeptides are characterized by the presence of two cis peptide bonds at HyLeu(2)-Pro(3)/HyLeu(2)-β-MePro(3) and NMeVal(5)-NMePhe(6), respectively. In isaridin A, a strong intramolecular H-bond is observed between Phe(4)CO...HNβ-Gly(1), and a similar, but weaker, interaction is observed between β-Gly(1)COHNPhe(4). In contrast, in isaridin B, only a single intramolecular H-bond is observed between β-Gly(1)CO...HNPhe(4)

Modeling temporal variations of electrical resistivity associated with pore pressure change in a kilometer-scale natural system

International audienceFrom 1995 to 1998 the natural electric field was monitored with an array of 20 dipoles on a ridge separating two reservoir lakes in the French Alps. The experiment was run to study the correlation between the electric potential variations and transient deformations of the ridge in association with the annual cycle of lake level variations. Large distortion of the induced electric field is observed and is found almost purely static and well correlated to the geology. A simple DC 3-D model is constructed, and resistivity structures that create the distortion are identified. The electrically resistive crystalline bedrock strongly amplifies the static distortion caused by the heterogeneous geology on the ridge. The temporal variations of the electric distortion observed over two years are associated with the lake level cycle. The model suggests that a resistivity variation of the order of 20% in the bedrock can account for the observed seasonal time-varying distortion. The resistivity change could be explained in terms of pore and crack geometry change controlled by stress. This study suggests that in particular geological contexts, electrical resistivity changes in structures can be detected through an amplification of the static distortion of the induced electric field. The results provide a framework to interpret some observations of electric field variations possibly associated with tectonic activity. The galvanic coupling model proposed here is an alternative to the streaming potential effect model, and it defines new criteria for the surface detection of groundwater in the crust

Epigenetic profile of the euchromatic region of human Y chromosome

The genome of a multi-cellular organism acquires various functional capabilities in different cell types by means of distinct chromatin modifications and packaging states. Acquired during early development, the cell type-specific epigenotype is maintained by cellular memory mechanisms that involve epigenetic modifications. Here we present the epigenetic status of the euchromatic region of the human Y chromosome that has mostly been ignored in earlier whole genome epigenetic mapping studies. Using ChIP-on-chip approach, we mapped H3K9ac, H3K9me3, H3K27me3 modifications and CTCF binding sites while DNA methylation analysis of selected CpG islands was done using bisulfite sequencing. The global pattern of histone modifications observed on the Y chromosome reflects the functional state and evolutionary history of the sequences that constitute it. The combination of histone and DNA modifications, along with CTCF association in some cases, reveals the transcriptional potential of all protein coding genes including the sex-determining gene SRY and the oncogene TSPY. We also observe preferential association of histone marks with different tandem repeats, suggesting their importance in genome organization and gene regulation. Our results present the first large scale epigenetic analysis of the human Y chromosome and link a number of cis-elements to epigenetic regulatory mechanisms, enabling an understanding of such mechanisms in Y chromosome linked disorders

Intuitionistic Fuzzy Time Series Functions Approach for Time Series Forecasting

Fuzzy inference systems have been commonly used for time series forecasting in the literature. Adaptive network fuzzy inference system, fuzzy time series approaches and fuzzy regression functions approaches are popular among fuzzy inference systems. In recent years, intuitionistic fuzzy sets have been preferred in the fuzzy modeling and new fuzzy inference systems have been proposed based on intuitionistic fuzzy sets. In this paper, a new intuitionistic fuzzy regression functions approach is proposed based on intuitionistic fuzzy sets for forecasting purpose. This new inference system is called an intuitionistic fuzzy time series functions approach. The contribution of the paper is proposing a new intuitionistic fuzzy inference system. To evaluate the performance of intuitionistic fuzzy time series functions, twenty-three real-world time series data sets are analyzed. The results obtained from the intuitionistic fuzzy time series functions approach are compared with some other methods according to a root mean square error and mean absolute percentage error criteria. The proposed method has superior forecasting performance among all methods

Professional values of Singapore journalists.

The purpose of the study was to discover the professional values, ethics and roles of the Singapore journalists on whom little research is available. The study partially replicated past research done in the United States by Johnstone et al (1971), and Weaver and Wilhoit (1982, 1992).Replications of these studies done in Australia (1992) and Hong Kong(1996) have also been used as comparisons. It was found that Singapore journalists shared some demographic similarities with their counterparts in these different countries, though they had limited journalism training. The Singapore journalists were also found to assume the role of the Interpretive-Disseminator which best suits their political and social surroundings. This role also fitted well into the Development and Social Responsibility theories of the press that the Singapore system is based on.​Master of Mass Communicatio

Investigations on the contribution of AtNRT2.6 gene to nitrate transport in Arabidopsis thaliana

Completion of the Arabidopsis genome helped to identify seven members of the NRT2 family (Nitrate Regulated Transport) that encode high-affinity nitrate transport. Extensive genetic and physiological studies have confirmed the primary role of AtNRT2.1 in induced high-affinity nitrate transport (IHATS). Moreover it is evident that AtNRT2.1 demonstrates functional association with another gene, AtNAR2 that functions as a part of a two-component system at the plasma membrane for the IHATS. Here we have investigated the contribution of AtNRT2.6 gene to nitrate transport by combining molecular and physiological studies in Arabidopsis thaliana WT, Atnrt2.6 T-DNA mutant and a AtNRT2.6:GFP transformant line of Arabidopsis thaliana. RT-PCR data from un-induced and nitrate re-induced plants demonstrated the constitutive expression of AtNRT2.6 gene in roots, shoots and in flowers. The transcript levels and tissue specific expression of AtNRT2.6:GFP in root cortical cells and in pollen have confirmed the previous AtNRT2.6Science, Faculty ofBotany, Department ofGraduat

GAMAKA AND VADANABHEDA: A STUDY OF SOMANATHA\u27S RAGAVIBODHA IN HISTORICAL AND PRACTICAL CONTEXT

One of the most striking aspect of Indian classical music is the particular quality of its melodic material. This quality is achieved, among other things, through the different techniques of ornamentations of the various scale degrees in the music. The term for ornament in Indian music texts is gamaka. The present dissertation is an historical and critical study of the gamaka. Among the many music treatises that describe the gamakas, Somanatha\u27s Ragavibodha (dated 1609 A.D.) is the most important because it is the only text that has an entire chapter on ornaments. Somanatha has called these ornaments vadana-bhedas and has created notational symbols for them after having described, in detail, their realizations on the contemporaneous fretted instrument, the rudra v(\u27)ina. Further, he has exemplified the vadana-bhedas by incorporating them in his extensive music examples. Somanatha has acknowledged that his vadana-bhedas were based on the gamakas and sthayas (components of a raga) encountered in the Sang(\u27)ita-ratnakara (13thc. A.D.) and other earlier texts. A study of these texts clearly indicate that (1) the gamakas and the sthayas were primarily vocal techniques and (2) the rudra v(\u27)ina was a post thirteenth century instrument. So it is in Ragavibodha that an attempt has been made for the first time, in descriptive tradition, to describe instrumental performance reflecting vocal techniques. Somanatha has described twenty vadana-bhedas plus three other terms to indicate (1) specific registral positions of the scale degrees and (2) phrase endings. A study of the vadana-bheda techniques indicates that most of them fall roughly into four categories, namely, (1) fingering, (2) deflection, (3) slides and (4) others. The name of each vadana-bheda is either reflective of its specific action and/or its resulting realization. An analysis of the distribution of the various types of the vadana-bhedas in the musical illustrations in Ragavibodha indicates that there are in each of the first three categories, at least one type that is widely distributed either singly or in combination and some that occur rarely, again either singly or in combination. Further, it also indicates that some combinations are widely distributed, whereas some others are narrowly restricted. Though there is no one-to-one correspondence between the gamakas of the earlier texts and the vadana-bhedas of Ragavibodha, there is enough correspondence, however tenous, between these two sets of ornamentation descriptions to indicate some degree of historical influence. Two post-Ragavibodha works, namely, Sang(\u27)ita-parijata of Pandita Ahobala and Raga-tatva-vibodha of(\u27 )Sr(\u27)inivasa, are other important works that describe ornamentation with reference to the v(\u27)ina. However, the ornaments are designated gamakas. Though there are these texts on music, contemporary performance practices belong to oral traditions. In this dissertation, only the Karnatic tradition, in which the author is trained, is examined with reference to the gamakas. The ten gamakas of the oral Karanatic tradition may be traced back to the middle of the eighteenth century; there are some texts that describe the ten types of gamakas. However, there is no consistency about either the names or the orderings of these gamakas in the oral tradition. Some of the names of these gamakas reflect their relationship to the gamakas and vadana-bhedas in the textual tradition either nominally or functionally or both. It is important to reiterate that Somanatha was the first theorist, in the descriptive tradition, to attempt to describe in his Ragavibodha instrumental vadana-bhedas based on vocal gamakas. He was also the first to describe, with adequate notation using these vadana-bhedas, actual music of his time through extensive music examples