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Measurement of emission diameter as a function of time on foam z- pinch plasmas
We have developed a streaked imaging capability to make time-resolved measurements of the emission size for low density foam z-pinches. By lens coupling visible emission from the z-pinch target to an array of fiber optics we obtained the emission profile in the visible as a function of time with radial resolution of 300 {mu}m. To measure the emission at temperatures greater than {approx}40 eV the source was slit-imaged or pin-hole imaged onto an x-ray filtered scintillator. Non-uniformities in both visible and x-ray emission were observed. We describe the diagnostics, the image unfold process, and results from the instrument for both visible and x-ray measurements
Derivation of Del180 from sediment core log data\u27 Implications for millennial-scale climate change in the Labrador Sea
Sediment core logs from six sediment cores in the Labrador Sea show millennial-scale climate variability during the last glacial by recording all Heinrich events and several major Dansgaard-Oeschger cycles. The same millennial-scale climate change is documented for surface water δ18O records of Neogloboquadrina pachyderma (left coiled); hence the surface water δ18O record can be derived from sediment core logging by means of multiple linear regression, providing a paleoclimate proxy record at very high temporal resolution (70 years). For the Labrador Sea, sediment core logs contain important information about deepwater current velocities and also reflect the variable input of ice-rafted debris from different sources as inferred from grain-size analysis, the relation of density and P wave velocity, and magnetic susceptibility. For the last glacial, faster deepwater currents, which correspond to highs in sediment physical properties, occurred during iceberg discharge and lasted from several centuries to a few millennia. Those enhanced currents might have contributed to increased production of intermediate waters during times of reduced production of North Atlantic Deep Water. Hudson Strait might have acted as a major supplier of detrital carbonate only during lowered sea level (greater ice extent). During coldest atmospheric temperatures over Greenland, deepwater currents increased during iceberg discharge in the Labrador Sea, then surface water freshened shortly thereafter, while the abrupt atmospheric temperature rise happened after a larger time lag of ≥ 1 kyr. The correlation implies a strong link and common forcing for atmosphere, sea surface, and deep water during the last glacial at millennial timescales but decoupling at orbital timescales
Hepatitis B virus genotypes and mutations in the basal core promoter and pre-core/core in chronically infected patients in southern Brazil: a cross-sectional study of HBV genotypes and mutations in chronic carriers
Factors influencing gestational age-adjusted birthweight in a natonal series of 600 newborns from mothers with HIV.
Background: Few studies have assessed the determinants of birthweight in newborns from HIV-positive mothers in analyses that adjusted for different gestational age at delivery. Method: We calculated gestational age-adjusted birthweight Z-score values in a national series of 600 newborns from women with HIV and in 600 newborns from HIV-negative women matched for gender and gestational age. The determinants of Z-score values in newborns from HIV-positive mothers were assessed in univariate and multivariate regression analyses. Results: Compared to newborns from HIV-negative women, newborns from HIV-positive women had significantly lower absolute birthweight (2799 vs. 2887 g; p = .007) and birthweight Z score (-0.430 vs. -0.222; p 10 cigarettes/day (ZSD 0.323, 95% CI 0.129-0.518, p = .001), absence of pregnancies in the past (ZSD 0.200, 95% CI 0.050-0.349, p = .009), no antiretroviral treatment in the past (ZSD 0.186, 95% CI 0.044-0.327, p = .010), and Caucasian ethnicity compared to Hispanic (ZSD 0.248, 95% CI 0.022-0.475, p = .032). Body mass index (BMI) at conception and maternal glycemia levels during pregnancy were also significantly related to birthweight Z scores. Glycemia, BMI, and recent substance use maintained a significant association with Z-score values in multivariate analyses. In the multivariate analysis, the only factors significantly associated with Z-score values below the 10th percentile were recent substance use (adjusted odds ratio [AOR] 3.17, 95% CI 1.15-8.74) and smoking (AOR 2.26, 95% CI 1.13-4.49). Discussion: We identified several factors associated with gestational age-adjusted birthweight in newborns from women with HIV. Smoking and substance use have a significant negative impact on intrauterine growth, which adds to an independent HIV-related effect on birthweight. Prevention and information on this issue should be reinforced in women with HIV of childbearing age to reduce the risk of negative outcomes in their offspring
Factors influencing gestational age-adjusted birthweight in a national series of 600 newborns from mothers with HIV.
Predicting Sexual Harassment From Hostile Sexism and Short-Term Mating Orientation: Relative Strength of Predictors Depends on Situational Priming of Power Versus Sex
Acoustic Lexemes for Organizing Internet Audio
In this article, a method is proposed for automatic fine-scale audio description that draws inspiration from ontological sound description methods such as Shaeffer's Objets Sonores and Smalley's Spectromorphology. The goal is complete automation of audio description at the level of sound objects for indexing and retrieving sound segments within Internet audio documents. To automatically segment audio documents into acoustic lexemes, a hidden Markov model is employed. It is demonstrated that the symbol stream of cluster labels, generated by the Viterbi algorithm, constitutes a detailed description of audio as a sequence of spectral archetypes. The ASCII base-64 encoding scheme maps cluster indices to one-character symbols that are segmented into 8-gram sequences for indexing in a relational database. To illustrate the methods, the essential components of an audio search engine are described: the automatic cataloguer, the retrieval engine and the query language. The results of experiments that test the accuracy and the retrieval efficiency of six new similarity-matching algorithms for audio using acoustic lexemes are presented. The article concludes with examples of audio matching using the structured query language (SQL) for creating new musical sequences from large extant audio collections
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