Slug mechanism in horizontal duct and simulation based on one dimensional two fluid dynamics

Thesis--University of Tsukuba, D.Eng.(A), no. 756, 1990. 3. 2

Simulation of optical interstellar scintillation

Stars twinkle because their light propagates through the atmosphere. The same phenomenon is expected on a longer time scale when the light of remote stars crosses an interstellar turbulent molecular cloud, but it has never been observed at optical wavelengths. The aim of the study described in this paper is to fully simulate the scintillation process, starting from the molecular cloud description as a fractal object, ending with the simulations of fluctuating stellar light curves. Fast Fourier transforms are first used to simulate fractal clouds. Then, the illumination pattern resulting from the crossing of background star light through these refractive clouds is calculated from a Fresnel integral that also uses fast Fourier transform techniques. Regularisation procedure and computing limitations are discussed, along with the effect of spatial and temporal coherency (source size and wavelength passband). We quantify the expected modulation index of stellar light curves as a function of the turbulence strength --characterised by the diffraction radius $R_{diff}$-- and the projected source size, introduce the timing aspects, and establish connections between the light curve observables and the refractive cloud. We extend our discussion to clouds with different structure functions from Kolmogorov-type turbulence. Our study confirms that current telescopes of ~4m with fast-readout, wide-field detectors have the capability of discovering the first interstellar optical scintillation effects. We also show that this effect should be unambiguously distinguished from any other type of variability through the observation of desynchronised light curves, simultaneously measured by two distant telescopes.Comment: 11 pages, 11 figures, accepted for publication in Astronomy and Astrophysic

Cytogenetic Evaluation of Couples With Spontaneous Abortion, Still Birth and Recurrent Miscarriage in Qazvin: Report and Review

Background: Chromosomal abnormality plays an important role in different types of miscarriages. Objectives: The present study was designed to investigation chromosomal anomalies in three groups of couples with recurrent abortion (RA), spontaneous abortion (SA) and still birth (SB). PatientsandMethods: In this retrospective study, the frequency of chromosomal aberrations was investigatedamong 260 couples with miscarriage, which had referred to the cytogenetic section of a reference laboratory in Buali hospilal, Qazvin, Iran from 2009 to 2014. Metaphase spreads were analyzed using G-banding. Results: In this study, 7.6% of couples had chromosomal aberrations including, balanced reciprocal translocations, robertsonian translocations, inversions and sex chromosome aneuploidy. Frequency of balanced translocations was higher, specifically in couples with SA. Conclusions: In this investigation we showed that chromosomal abnormalities could be one of the important causes of miscarriages. Cytogenetic evaluation of couples, which experienced different types of miscarriage, may prevent unnecessary treatments. Keywords: Recurrent Abortion, Spontaneous Abortion, Still Birth, Chromosome Abnormalit

Sky reconstruction from transit visibilities: PAON-4 and Tianlai Dish Array

The spherical harmonics $m$-mode decomposition is a powerful sky map reconstruction method suitable for radio interferometers operating in transit mode. It can be applied to various configurations, including dish arrays and cylinders. We describe the computation of the instrument response function, the point spread function (PSF), transfer function, the noise covariance matrix and noise power spectrum. The analysis in this paper is focused on dish arrays operating in transit mode. We show that arrays with regular spacing have more pronounced side lobes as well as structures in their noise power spectrum, compared to arrays with irregular spacing, specially in the north-south direction. A good knowledge of the noise power spectrum $C^{\mathrm{noise}}(\ell)$ is essential for intensity mapping experiments as non uniform $C^{\mathrm{noise}}(\ell)$ is a potential problem for the measurement of the HI power spectrum. Different configurations have been studied to optimise the PAON-4 and Tianlai dish array layouts. We present their expected performance and their sensitivities to the 21-cm emission of the Milky Way and local extragalactic HI clumpsComment: 20 pages, 18 figures - Submitted to MNRAS ( the appendix A,B are not included in the accepted version

Food-dependent exercise-induced anaphylaxis due to wheat in a young woman

Food Dependent Exercise-Induced Allergy is a rare condition. However, the occurrence of anaphylaxis is increasing especially in young people. The diagnosis of anaphylaxis is based on clinical criteria and can be supported by laboratory tests such as serum tryptase and positive skin test results for specific IgE to potential triggering allergens. Anaphylaxis prevention needs strict avoidance of confirmed relevant allergen. Food-exercise challenge test may be an acceptable method for diagnosis of Food Dependent Exercise-Induced Allergy and dietary elimination of food is recommended to manage it. In this study, a 32 year-old woman visited the allergy clinic with a history of several episodes of hives since 11 years ago and 3 life-threatening attacks of anaphylaxis during the previous 6 months. The onsets of majority of these attacks were due to physical activity after breakfast. On Blood RAST test, the panel of common food Allergens was used and she had positive test only to wheat flour. On skin prick tests for common food allergens she showed a 6 millimeter wheal with 14 mm flare to Wheat Extract. The rest of allergens were negative. The patient was diagnosed as wheat-dependent exercise-induced, and all foods containing wheat were omitted from her diet. In this report we emphasized on the importance of careful history taking in anaphylaxis diagnosis

Sky reconstruction for the Tianlai cylinder array

In this paper, we apply our sky map reconstruction method for transit type interferometers to the Tianlai cylinder array. The method is based on the spherical harmonic decomposition, and can be applied to cylindrical array as well as dish arrays and we can compute the instrument response, synthesised beam, transfer function and the noise power spectrum. We consider cylinder arrays with feed spacing larger than half wavelength, and as expected, we find that the arrays with regular spacing have grating lobes which produce spurious images in the reconstructed maps. We show that this problem can be overcome, using arrays with different feed spacing on each cylinder. We present the reconstructed maps, and study the performance in terms of noise power spectrum, transfer function and beams for both regular and irregular feed spacing configurations.Comment: 15 pages, 12 figures, accepted by RA

The effect of sesame oil on the liver phosphatidate phosphohydrolase and serum lipoproteins in hypercholesterolemic rabbits

Background and Aim: Nowadays, the effect of medicinal plants on the reduction of the prevalence of cardiovascular diseases and atherosclerosis has been confirmed. Liver phosphatidate phosphohydrolase (PAP) is a key regulatory enzyme in the glycerolipid metabolism. The aim of this study was to assess the effects of sesame oil on liver PAP activity, liver triglyceride, liver cholesterol and serum lipoprotein levels in hypercholesterolemic rabbits. Material and Methods: In this experimental study 27 New Zealand rabbits were randomly assigned to 3 groups (n=9). Group1 (control) was fed with standard diet. Group II (hypercholesterolemic group) animals received hypercholesterolemic diet (1) without treatment. Group III was fed with hypercholesterolemic diet (1) plus sesame oil (5). After two months, liver PAP activity, liver triglyceride and cholesterol content, serum lipoproteins and malondialdehyde, and antioxidant capacity were measured. One way ANOVA was used for analysis of the mean values of the variables and for pair-wise comparison of the groups we used Tukey's test. Results: Group III had a significant decrease (P< 0.05) in the liver PAP activity compared to group II. In group II, consumption of the enriched cholesterol diet led to a significant elevation (P< 0.05) in serum lipoproteins compared to group I (control). Also, sesame oil in group III decreased the serum lipoproteins, liver triglyceride, and liver cholesterol in comparison to group II (p<0.05). However, a significant elevation (P< 0.05) in serum antioxidant capacity and a significant reduction in malondialdehyde level occurred in group III compared to group II (P<0.05). Conclusion: Sesame oil can be effective in reducing risk factors of cardiovascular diseases by decreasing serum lipids through making desirable alterations in serum lipoproteins. Also addition of sesame oil to hypercholesterolemic diets can reduce the liver PAP activity resulting in reduced liver triglyceride synthesis, which can decrease the risk of development of fatty liver in hypercholesterolemic diets

Identification of KPC-producing Klebsiella pneumoniae in clinical samples in Iran

Background :Nowadays beta lactamase-producing multiple-drug resistance Klebsiella pneumoniae is as an important factor in nosocomial infections which has produced therapeutic difficulties in worldwide. The purpose of this study was to identify KPC-producing K. pneumoniae (blakpc) in clinical samples in Iran. Materials and Methods: After identification of isolates in species level using cultural and biochemical methods, the susceptibility tests were carried out on 180 isolates of K. pneumoniae using disk diffusion method. Also MIC (Minimum inhibitory concentrations) was determined for meropenem and imipenem. Then all isolates of Klebsiella were considered for presence of blakpc gene by PCR. Results: In this study of 202 isolates of Klebsiella, 180 isolates (89.1%) of K. pneumoniae and 22 isolates (10.9%) of Klebsiella oxytoca were isolated from patients. More than 55% of isolates showed multiple-drug resistance and also above 40% resistance to imipeneme and meropeneme was recorded. The MIC of isolates which were resistant to carbapenemes was above 32µg/ml.The PCR results showed that 22 cases (11.9%) of isolates had blakpc gene which most of them had been isolated from urine and blood samples of patients who were hospitalized in the ICU and pediatrics. Conclusion: Regarding the existence of blakpc gene in K. pneumoniae and possibility of transformation of these genes to the other bacteria, reconsideration in antibiotics consumption patterns and more attention to nosocomial infections control criteria are inevitable

Development of a decision support tool for automation adoption and optimisation in precast concrete plants : a New Zealand case study : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Construction Project Management at Massey University, Albany, New Zealand

In response to the growing demand in the New Zealand construction market, this study aims to develop a decision-support framework for adopting and optimising automation in precast concrete plants, which are increasingly recognised for their numerous benefits. The primary resources required by these plants include labour, equipment, and materials, and their efficient use is essential for maintaining competitiveness. Automation has been identified as a potential solution for improving productivity and profitability in precast concrete manufacturing; however, an appropriate decision-support tool is currently lacking. The current study commences with a comprehensive literature review, followed by historical data collection, face-to-face interviews, and site observations of precast concrete plants to address this research gap. These methods help identify attributes that affect profitability, leading to developing and validating of a theoretical framework named the Precast Plant Automation System Tool (PPAST) through a case study. The PPAST framework comprises two sequential phases: the strategic phase, which uses the direct rating method for preliminary feasibility evaluation of automation adoption, and the tactical phase, where the AHP method assesses the appropriate automation sequence for the plant. The study’s main findings indicate that the developed decision support system enables decision-makers to articulate their objectives and attitudes towards risk as they explore the feasibility of automation and formulate an optimal automation strategy. Specifically, the system aids in evaluating the impact of automation on cost and quality and identifying necessary process changes before implementing new technologies. The primary contribution of this research is its novel approach to systematically evaluating alternative automation scenarios in precast concrete production plants. The results demonstrate that the proposed model is a valuable and effective decision-making tool for adopting and optimising automation in precast concrete plants. This research fills a critical knowledge gap concerning the crucial measurements of precast concrete plant profitability and the absence of an automation adoption tool. The developed framework can be extended to investigate automation adoption and optimisation in other precast concrete plants across New Zealand. This study's practical implications include empowering precast plants to meet their organisation's profitability measures, thus satisfying stakeholder value propositions. A thriving precast concrete industry will lead to more satisfied clients, attract additional investment, and improve the overall construction industry's quality, productivity, and profitability at the national level. Theoretically, this research contributes a reliable benchmark for future studies by developing decision support tools that facilitate selecting optimised automation methods for precast concrete plants and contributing to theoretical knowledge by establishing an optimised automation decision support method that guides researchers in exploring other avenues for maximising profitability