361 research outputs found

    Morphometric and meristic variations in bream (Abramis brama orientalis, Berg, 1949) during larval development

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    This study was conducted to examine morphometric and meristic characteristics alongside pigmentation patterns of bream larvae, Abramis brama orientalis, in four stages of larval development. Morphological characters including total length (TL), standard length (SL), notochord length (NL), head length (HL), head depth (HD), eye diameter (ED) and mouth width (MW) were examined from hatching time through 30 days after hatching (DAH). The results showed morphometric variations in the different larval stages. Growth and development of fins occurred mainly at the Post Flexion stage with the completion of caudal fin at 9 mm TL and pelvic fin at 13.33 mm TL. At all larval stages, the highest concentration of pigments was seen on dorsal, ventral and somewhat on the lateral sides of body in descending order. The highest density of melanophores at larvae yolk sac stage was observed on the yolk sac and the back of head zone, while at preflexion and flexion stages melanophores were dominant on the back of head and on the skin folds which resulted from yolk absorption. At post flexion stage, high density of melanophores was found on the back of the head, bases of fins and caudal fin, while less concentrations of these cells were evident on the lateral sides of fish' body. In conclusion, a clear change in the growth and main morphological characters were observed in postflexion stage. This may be due to the main development of fins, which would suggest enhanced swimming capabilities and also prey capture efficiencies

    New hybrid CPU-GPU solver for CFD-DEM simulation of fluidized bed

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    Modeling is an alternative to experiment to explore more in multiphase flows. Various modeling approaches have been developed and used from 1D models in the macro-scale to multidimensional models in the micro scale. Well-known modeling approaches for fluidization systems are TFM and CFD-DEM, both have found many practical applications in fluidization systems. The TFM considers both fluid and particulate phase as interpenetrating continua. In contrast, the CFD-DEM considers the fluid as a continuous fluid in the meso-scale (cell-scale) and the solid as discrete particles in the micro-scale. The translational and rotational motions of individual particles are described by applying Newton’s and Euler’s second laws of motion, respectively. Since the first introduction of CFD-DEM technique by Tsuji et al. (1) and Hoomans et al. (2), different aspects of this modeling approach have been being enhanced and developed. Nowadays, this modeling approach has found many applications in different engineering fields specially fluidization (3). One of the main limitations of this modeling approach is its high computational demand which makes the parallelization necessary in order to model larger systems with more details. A CFD-DEM code comprises of three computational parts: CFD, DEM and coupling. The CFD part can be efficiently parallelized using space decomposition method on the distributed-memory platform like MPI, while the DEM part, due to its low granularity, is better to be parallelized using loop-level parallelization on the shared-memory platform like CUDA. We used a combination of both platforms to speed-up the CFD-DEM code. Figure 1 shows the data transfer between different parts of the code and the platforms that are used for their implementation. As it can be seen, the CFD and coupling parts are parallelized using MPI and executed on multiple CPUs and the DEM part is parallelized using CUDA and executed on a GPU. To solve the Navier-Stokes equations, we used the open-source CFD package, OpenFOAM®, while the code for coupling and DEM calculations were developed internally. The main goal of this programing style was to benefit from the maximum computational power of CPU and GPU in a single PC equipped with a CUDA-capable GPU. This code was successfully utilized for a fluidization system containing 100,000 spherical particles with the mean size of 2200 micrometers and density of 1500 kg/m3. Particles were placed in a cylinder with inner diameter of 0.14 m and height of 1 m. Number of fluid cells in the simulation was 7,400. The superficial gas velocity was 2 m/s. The code was executed on one CPU core of an Intel® core™-i7 processor (3.6 GHz) and an NVIDIA GeForce® GTX 660 Ti GPU. The simulation was continued for 1 second and the execution time was about 1.5 hr. Snapshots of this simulation are shown in Figure 2. These snapshots show the contour of gas velocity field and particles which are colored based on their velocity. This code is in its very first stages of developments and needs optimizations in both coupling and DEM parts to gain more execution speed. Please click Additional Files below to see the full abstract

    Effects of Zataria multiflora and Eucalyptus globolus essential oils on haematological parameters and respiratory burst activity in Cyprinus carpio

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    The present study was undertaken to investigate the effects of Zataria multiflora and Eucalyptus globolus essential oils on some haematological parameters and respiratory burst activity in common carp (Cyprinus carpio). 260 fish (30±5g) were randomly distributed in 13 treatment groups; each one in three replicates and different doses of essential oils in 16-17ºC were administrated. The fish were sampled on day 1, 2, 8, 15 and 22 after the 8-day trial. Haematological parameters (red blood cell count, haematocrit) and respiratory burst activity were then evaluated in all treatment groups. The results suggest that essential oils especially Zataria multiflora in dietary intake significantly enhanced respiratory burst activity of blood neutrophlis (P< 0.05). Meanwhile, essential oils had moderate effects on RBC and haematocrit. Significant increases in RBC and haematocrit levels were just noted in T11 treatment group (P< 0.05). This study indicates that dietary administration of Zataria multiflora and Eucalyptus globolus essential oils could be used to promote the health status of common carp during temperature stress

    The effect of saffron supplementation on blood glucose and lipid profile: A systematic review and meta-analysis of randomized controlled trials

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    Background: Despite several studies about the effects of saffron supplementation on serum concentrations of lipid and glucose profiles, no systematic study had summarized the findings. Therefore, we conduct current study to systematically summarize findings from studies about the effect of saffron supplementation on serum levels of glucose and lipid profiles and to do a meta-analysis, if possible. Methods: A systematic literature search was conducted for clinical trials published in PubMed, SCOPUS, EMBASE, Cochrane's Library and ISI Web of Science from the beginning to 22 February 2019. All randomized clinical trials on the effect of saffron supplementation on serum concentrations of lipid and glucose profiles were included. Results: In overall, six studies were included in the current study. Pooled analysis of six studies for the effect of saffron on serum TG, TC and FBG concentrations and of five studies for LDL and HDL, showed a significant reduction in TG (WMD: -8.93 mg/dl; 95 CI: -16.49 to -1.37, P = 0.02) and TC levels (WMD: -5.72 mg/dl; 95 CI: -11.10 to -0.34, P = 0.03), a significant increase in HDL levels (WMD: 2.7 mg/dl; 95 CI: 0.22 to 5.18, P = 0.03), and no significant effect on LDL (WMD: -2.30 mg/dl; 95 CI: -11.73 to 7.13, P = 0.63) and FBG levels (WMD: -5.30 mg/dl; 95 CI: -14.20 to 3.60, P = 0.51). Conclusion: We found a significant reduction in serum concentrations of TC and TG and a significant increase in serum levels of HDL following supplementation with saffron. Saffron supplementation had no significant influence on serum FPG and LDL concentrations. © 2019 Elsevier Lt

    Antimicrobial Electrodeposited Silver-Containing Calcium Phosphate Coatings

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    Biocompatible antimicrobial coatings may enhance the function of many orthopedic implants by combating infection. Hydroxyapatite is a choice mineral for such a coating as it is native to bone and silver would be a possible antimicrobial agent as it is also commonly used in biomedical applications. The aim of the research is to develop a silver-containing calcium phosphate (Ag/Ca-P) coating via electrochemical deposition on titanium substrates as this allows for controlled coating buildup on complex shapes and porous surfaces. Two different deposition approaches are explored: one-step Ag/Ca-P(1) deposition coatings, containing silver ions as microsized silver phosphate particles embedded in the Ca-P matrix; and via a two-step method (Ag/Ca-P(2)) where silver is deposited as metallic silver nanoparticle on the Ca-P coating. The Ag/Ca-P(1) coating displays a bacterial reduction of 76.1 +/- 8.3% via Ag-ion leaching. The Ag/Ca-P(2) coating displays a bacterial reduction of 83.7 +/- 4.5% via contact killing. Interestingly, by preincubation in phosphate-buffered saline solution, bacterial reduction improves to 97.6 +/- 2.7 and 99.7 +/- 0.4% for Ag/Ca-P(1) and Ag/Ca-P(2) coatings, respectively, due to leaching of formed AgClx(x-1)- species. The biocompatibility evaluation indicates that the Ag/Ca-P(1) coating is cytotoxic towards osteoblasts while the Ag/Ca-P(2) coating shows excellent compatibility. The electrochemical deposition of highly bactericidal coatings with excellent biocompatibility will enable us to coat future bone implants even with complex or porous structures

    Socio-economic, cultural, physical and ecological impact assessment of Kavar irrigation and drainage network in Iran

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    Environmental impacts assessment may be some measures to offset the impact to an acceptable level or explore new solutions. The research was conducted with the aim of assessing the socio-economic, cultural, physical and ecological impacts of Kavar irrigation and drainage network in Fars Province (Iran). In this study, Environmental impacts assessment was undertaken by ICOLD matrix. The ICOLD matrix is one of the flexible methods that converted qualitative data into quantitative data. In this method, the effect of the project activities on the environmental components were assessed in two stages; project construction and operation based on physical, ecological, socio-economic and cultural aspects. The findings indicated that positive effects will be generally exerted on the region environment by establishing and operating irrigation and drainage network in Kavar plain. In other words, substantial positive impacts will be seen in the region consequently; such as improving the average level of aquifer, enhancement of agricultural wells, and agriculture development in the region. However, in order to alleviate the negative impacts of the projects processes, it is suggested that presented environmental training to farmers, collaborating and further communicating with other relevant organizations and institutions.  </strong

    An ISP and end-user cooperative intradomain routing algorithm

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    The continuous growth in volume of Internet traffic, including VoIP, IPTV and user-generated content, requires improved routing mechanisms that satisfy the requirements of both the Internet Service Providers (ISPs) that manage the network and the end-users that are the sources and sinks of data. The objectives of these two players are different, since ISPs are typically interested in ensuring optimised network utilisation and high throughput whereas end-users might require a low-delay or a high-bandwidth path. In this paper, we present our UAESR (Utilisation-Aware Edge Selected Routing) algorithm, which aims to satisfy both players' demands concurrently by selecting paths that are a good compromise between the two players' objectives. We demonstrate by simulation that this algorithm allows both actors achieve their goals. The results support our argument that our cooperative approach achieves effective network resource engineering at the same time as offering routing flexibility and good quality of service to end-users

    Prevalence of blood-borne viruses among Iranian dentists: Results of a national survey

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    Objectives: Health care workers, including dentists, are at the front line for acquiring blood-borne virus infections. This study aimed to investigate the prevalence of hepatitis B, hepatitis C and human immunodeficiency viruses among Iranian dentists. Material and Methods: The survey included 1628 dental health care workers who attended the 51st annual Congress of the Iranian Dental Association. Data on the risk of blood-borne virus transmission during health care and infection control practices were gathered from self-administered questionnaires. Sera were screened serologically by enzyme-linked immunosorbent assay (ELISA). The positive samples were examined by polymerase chain reaction (PRC) followed by direct sequencing. Results: Six (0.36) and 81 (5.0) were positive for hepatitis B surface antigen (HBsAg) and (anti-hepatitis B virus core antigen (anti-HBc), respectively. Only 1 (0.061) was positive for anti-hepatitis C virus (anti-HCV). No case was positive for anti-human immunodeficiency virus (anti-HIV). One case was diagnosed as being occult hepatitis B virus (HBV) infection. One thousand five hundred thirty-five (94.3) of participants had received at least 1 dose of HBV vaccine. One thousand three hundred fifty-nine (88.5) contained hepatitis B surface antibody (anti-HBs) > 10 IU/ml, of whom 55 (4.0) were anti-HBc positive, suggesting that they had been infected with HBV in the past. Anti-HBc positive cases had past histories of hepatitis, either their own or their spouses'. Individuals with inadequate anti-HBs levels (< 10 IU/ml) were significantly more prevalent among anti-HBc positive cases (p < 0.001). Conclusions: The prevalence of blood-borne viruses among dental HCWs found in this study was lower than past reports from Iranian dentists and general population. The implementation of HBV vaccination together with improvement in infection control procedures has reduced the potential for risk infection among Iranian dentists
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