A study of the influence of Hg(6(3)P2) population in a low-pressure discharge on mercury ion emission at 194.2 nm

A low-pressure mercury-argon discharge, similar to the type existing in the mercury lamp for the trapped-ion standard, is probed with a new technique of laser spectroscopy to determine the influence of the Hg(6 3P(sub 2)) population on discharge emission. The discharge is excited with inductively coupled rf power. Variations in the intensity of emission lines in the discharge were examined as lambda = 546.1 nm light from a continuous wave (CW) laser excited the Hg(6 3P(sub 2)) to (7 3S (sub 1)) transition. The spectrum of the discharge viewed in the region of laser irradiation showed increased emission in lambda = 546.1, 435.8, 404.7, 253.7, and 194.2 nm lines. Other lines in Hg I exhibited a decrease in emission. When the discharge was viewed outside the region of laser irradiation, all lines exhibited an increased emission. Based on these results, it is concluded that the dominant mechanism for the excitation of higher lying levels of mercury is the the electron-impact excitation via the 3P(sub 2) level. The depopulation of this metastable is also responsible for the observed increase in the electron temperature when the laser irradiates the discharge. It is also concluded that the 3P(sub 2) metastable level of mercury does not play a significant role in the excitation of the 3P(sub 1/2) level of mercury ion

A Pareto Front Approach to Bi-objective of Distillation Column Operation Using Genetic Algorithm

In this paper, an exergy analysis approach is proposed for optimal design of distillation column by using Genetic algorithm. First, the simulation of a distillation column is performed by using the shortcut results and irreversibility in each tray is obtained. The area beneath the exergy loss profile is used as Irreversibility Index for exergy criteria. Then, two targets optimization algorithm (SA, Simulated Annealing) is used to maximize recovery and minimize irreversibility index in a column by six different variables (Feed Condition, Reflux Rate, Number of theoretical stage, Feed Trays (Feed Splitting, three variables)). SA uses one objective function for the purpose or alters two targets optimization to one target optimization. Then, GA optimization algorithm is used for two targets optimization except Pareto set which is used instead of objective function; finally, the results are compared with SA results. Then, one pump-around is considered to obtain better results (OPT2). Irreversibility index criterion is compared with exergetic efficiency, constant and variable feed composition splitters are considered.Key words: Exergy analysis; Irreversibility index; Genetic algorithm; Process optimization; Distillation colum

Molecular characterization and similarity relationships among sunflower (Helianthus annuus L.) inbred lines using some mapped simple sequence repeats

Information about the genetic diversity and relationships among breeding lines and varieties is not only useful for germplasm conservation and inbred line identification, but also for the selection of parental lines for quantitative trait loci (QTL) mapping as well as hybrid breeding in crops, including sunflower. In order to develop mapping populations, genetic distances among twenty eight sunflower genotypes were evaluated using simple sequence repeat (SSR) markers. One hundred and two markers were generated by 38 SSR loci and the mean for the number of allele per locus was 2.32. Polymorphism information content (PIC) values ranged from 0.09 (locus ha3555) to 0.62 (locus ORS598) with an average of 0.41. Jaccard's coefficient similarity matrix for the studied sunflower  genotypes varied from 0.25 to 0.9 indicating a broad genetic base. The maximum similarity (0.9) was observed between genotypes RT931 and ENSAT-R5, while the lowest similarity (0.25) was between genotypes LC1064C and LR64. Based on unweighted pair group method with arithmetic mean (UPGMA) clustering algorithm, the studied genotypes were clustered in four groups. However, some genotypes have the same specific characters that influence their clustering, and as a result, the results of the principal coordinate analysis (PCoA) largely corresponded to those obtained through cluster analysis.Key words: Cluster analysis, genetic diversity, principal coordinate analysis, sunflower, simple sequence repeat

Observation of light dragging in rubidium vapor cell

We report on the experimental demonstration of light dragging effect due to atomic motion in a rubidium vapor cell. We found that the minimum group velocity is achieved for light red-shifted from the center of the atomic resonance, and that the value of this shift increases with decreasing group velocity, in agreement with the theoretical predictions by Kocharovskaya, Rostovtsev, and Scully [Phys. Rev. Lett. {\bf 86}, 628 (2001)].Comment: 4 pages 4 figures, submitted to PR

Detection and imaging in strongly backscattering randomly layered media

Abstract. Echoes from small reflectors buried in heavy clutter are weak and difficult to distinguish from the medium backscatter. Detection and imaging with sensor arrays in such media requires filtering out the unwanted backscatter and enhancing the echoes from the reflectors that we wish to locate. We consider a filtering and detection approach based on the singular value decomposition of the local cosine transform of the array response matrix. The algorithm is general and can be used for detection and imaging in heavy clutter, but its analysis depends on the model of the cluttered medium. This paper is concerned with the analysis of the algorithm in finely layered random media. We obtain a detailed characterization of the singular values of the transformed array response matrix and justify the systematic approach of the filtering algorithm for detecting and refining the time windows that contain the echoes that are useful in imaging

Comprehensive Characterization of Mesenchymal Stem Cells from Human Placenta and Fetal Membrane and Their Response to Osteoactivin Stimulation

Mesenchymal stem cells (MSCs) are the most promising seed cells for cell therapy and can be isolated from various sources of human adult tissues such as bone marrow (BM-MSC) and adipose tissue. However, cells from these tissues must be obtained through invasive procedures. We, therefore, characterized MSCs isolated from fresh placenta (Pl-MSC) and fetal membrane (Mb-MSC) through morphological and fluorescent-activated cell sorting (FACS). MSC frequency is higher in membrane than placenta (2.14%  ± 0.65 versus 15.67%  ± 0.29%). Pl/Mb-MSCs in vitro expansion potential was significantly higher than BM-MSCs. We demonstrated that one of the MSC-specific marker is sufficient for MSC isolation and that culture in specific media is the optimal way for selecting very homogenous MSC population. These MSCs could be differentiated into mesodermal cells expressing cell markers and cytologic staining consistent with mature osteoblasts and adipocytes. Transcriptomic analysis and cytokine arrays demonstrated broad similarity between placenta- and membrane-derived MSCs and only discrete differences with BM-MSCs with enrichment of networks involved in bone differentiation. Pl/Mb-MSCs displayed higher osteogenic differentiation potential than BM-MSC when their response to osteoactivin was evaluated. Fetal-tissue-derived mesenchymal cells may, therefore, be considered as a major source of MSCs to reach clinical scale banking in particular for bone regeneration

Theoretical Aspects of the Equivalence Principle

We review several theoretical aspects of the Equivalence Principle (EP). We emphasize the unsatisfactory fact that the EP maintains the absolute character of the coupling constants of physics while General Relativity, and its generalizations (Kaluza-Klein,..., String Theory), suggest that all absolute structures should be replaced by dynamical entities. We discuss the EP-violation phenomenology of dilaton-like models, which is likely to be dominated by the linear superposition of two effects: a signal proportional to the nuclear Coulomb energy, related to the variation of the fine-structure constant, and a signal proportional to the surface nuclear binding energy, related to the variation of the light quark masses. We recall the various theoretical arguments (including a recently proposed anthropic argument) suggesting that the EP be violated at a small, but not unmeasurably small level. This motivates the need for improved tests of the EP. These tests are probing new territories in physics that are related to deep, and mysterious, issues in fundamental physics.Comment: 21 pages, no figures; submitted to a "focus issue" of Classical and Quantum Gravity on Tests of the Weak Equivalence Principle, organized by Clive Speake and Clifford Wil

Histopathological alterations in the gill of zebrafish (Danio rerio) exposed to Cr and Ba doped TiO2 nanoparticles

In order to improve the photocatalytic efficiency of titanium dioxide, doping it with metals has been suggested; however, toxicity studies of metal-doped nanoparticles on aquatic organisms are not completely known. Therefore, the purpose of this study was to evaluate the short term effect of exposure to Cr and Ba doped TiO2 nanoparticles (NPs) using gill histopathology of zebrafish (Danio rerio) under laboratory condition. In this study, four concentration levels, 1, 10, 32, and 100 mg L-1 of each Cr and Ba doped TiO2 NPs as well as a control group were used. After 4 days of exposure, from each experimental group, three samples of fish gill prepared to study the classic histology (haematoxylin - eosin). The results of this study showed that the Cr and Ba doped TiO2 NPs can cause gill alterations including aneurism, dilated and clubbed tips, hyperplasia, oedema, curvature, fusion of lamellae, increase of mucous secretion, and proliferation in the erythrocytes of cartilaginous core. The extent of tissue damages increased by concentration levels of NPs; however, the severity of injouries caused by Cr was more notable than that of observed by Ba. © 2016 BIOFLUX SRL. All rights reserved

Comparison of anthro-metabolic indicators for predicting the risk of metabolic syndrome in the elderly population: Bushehr Elderly Health (BEH) program

Background Metabolic syndrome (MetS) is a cluster metabolic disorder that includes central obesity, insulin resistance, hypertension, and dyslipidemia, and is highly associated with an increased risk of developing non-communicable diseases (NCDs). This study aimed to compare the reliability of anthro-metabolic indices [visceral adiposity index (VAI), body roundness index (BRI), and a body shape index (BSI), body adiposity index (BAI), lipid accumulation product (LAP), waist to hip ratio, and waist to height ratio] in predicting MetS in Iranian older people. Methods This cross-sectional study was conducted based on the data of 2426 adults aged ≥60 years that participated in the second stage of the Bushehr Elderly Health (BEH) program, a population-based prospective cohort study being conducted in Bushehr, Iran. MetS was defined based on the revised National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria. The receiver operating characteristic (ROC) curve analysis was used to assess predictive performance of anthro-metabolic indices and determine optimal cutoff values. Logistic regression analysis was applied to determine the associations between MetS and indices. Results 2426 subjects (48.1% men) with mean ± SD age of 69.34 ± 6.40 years were included in the study. According to ATP III criteria, 34.8% of men and 65.2% of women had MetS (P < 0.001). Of the seven examined indices, the AUCs of VAI and LAP in both genders were higher than AUCs of other anthro-metabolic indices. Also, in general population, VAI and LAP had the greatest predictive power for MetS with AUC 0.87(0.86–0.89) and 0.87(0.85–0.88), respectively. The lowest AUC in total population belonged to BSI with the area under the curve of 0.60(0.58–0.62). After adjusting for potential confounders (e.g. age, sex, education, physical activity, current smoking) in the logistic regression model, the highest OR in the total population was observed for VAI and LAP, which was 16.63 (13.31–20.79) and 12.56 (10.23–15.43) respectively. The lowest OR for MetS was 1.93(1.61–2.30) for BSI. Conclusion This study indicated that both VAI and LAP are the most valuable indices among the anthro-metabolic indices to identify MetS among the elderly in both genders. So, they could be used as proper assessment tools for MetS in clinical practice. However, the cost-benefit of these indices compared to the ATP III criteria need further studies