Design of Slotted and Slotless AFPM Synchronous Generators and their Performance Comparison Analysis by using FEA Method

Axial-flux permanent magnet machines are popular and widely used for many applications due to their attractive features such as light weight, low noise, high torque, robust and higher efficiency due to lack of field excitation. The main essence of this paper is to perform slotted and slotless axial-flux permanent magnet synchronous generator design based on theoretical sizing equations and then finite element analysis is reinforcement in order to get a more reliable and accuracy machine design. A comparative study of machine design and performances over the same rating but different configurations i.e., slotted and slotless are also discussed. And then, finite-element method (FEM) software was made for the slotted stator and slotless stator (AFPMSG) in order to compare their magnetic flux density and efficiency. The AFPMSG topology considered in this paper is a three-phase double-rotor single-stator topology with 16 pole-pairs, 2kW rated power and 188 rpm rated speed

Voltage Stability Assessment of Power System with Distributed Generation in Free and Open Source Software

This paper presents voltage stability analysis of distributed generation (DG) in mesh distribution network in Power System Analysis Toolbox (PSAT) — free and open source software. Voltage stability analysis of a power system is a necessity, particularly in the planning period of the development or expansion of a power network. The ultimate goal of this paper is to investigate the voltage stability of the 52 buses power system network (Mandalay City) during the expansion of the network. In this paper, a study is being done to expand the power network of the area of Mandalay City. In order to perform the voltage stability analysis, modal analysis as well as PV curves was evaluated based on load flow for selected scenarios. PSAT has been developed to carry out the static voltage stability analysis. And also the dynamic voltage stability analysis has been performed by using time domain simulation with PSAT software

A Fuzzy Logic Approach for Improvement of Power Quality Using FC-TCR

The reactive power compensation in a power distribution network plays a vital role in improving voltage and power system stability. The increase in the loading of the transmission lines sometimes can lead to voltage collapse due to the shortage of reactive power delivered at the load centers. This is due to the increased consumption of the reactive power in the transmission network and the characteristics of the load. All these problems can be removed by Static Var Compensator (SVC). Fixed capacitor thyristor controlled reactor (FC-TCR) can be used for power factor correction, flicker reduction, and steady-state voltage control, and also have the benefit of being able to filter out harmonics from the system. By changing firing angle of thyristor, voltage profile can be improved up to required level. The performance of FC-TCR with Fuzzy logic controller will be provided by using Matlab/Simulink. The installation site for this proposed system is Zone II Feeder of 132/33/11 kV 30MVA transformer in Tagondaing Substation

Upregulated CCL20 and CCR6 in Cancer Stem Cells Converted from Mouse iPS Cells

Background: Cancer stem cells (CSCs) as a class of malignant cancer cells play an important role in tumor progression. Previous studies by our group have demonstrated the establishment of the model of CSCs converting mouse iPS cells (miPSCs) into CSCs by treating the miPSCs with a conditioned medium (CM) of Lewis Lung Carcinoma (LLC) cells with or without the nonmutagenic chemical compounds. CSCs converted from miPSCs developed highly malignant adenocarcinoma when subcutaneously transplanted into the nude mice. Methods: The miPSCs were treated with each compound for 1 week in the presence of a CM of LLC cells. We evaluated the gene expression in the resultant CSCs comparing that in miPSCs by microarray analysis. And the expression of chemokine (C-C motif) ligand 20 (CCL20) and C-C chemokine receptor type 6 (CCR6) in converted cells were evaluated by rt-qPCR. The CCR6 expression in converted cells and primary cells were determined by flow cytometry. Results: As the result, the expression of CCL20 was found upregulated in the presence of CM supplemented with PD0325901. Then we assessed the expression of CCR6, which was considered to be stimulated by CCL20. Then the expression of CCR6 was also found up-regulated. Interestingly, IL17A expression was also observed only in the CSCs from the primary tumor implying the effect of tumor microenvironment. Moreover, significantly high level of CCR6 was showed in flow cytometric analysis. Conclusion: These results suggest that a model of CSCs with CCL20-CCR6 autocrine loop was obtained as the result of the conversion of iPSCs. This CSC should be a good model to study targeting CCR6 as a G protein-coupled receptor (GPCR)

Signaling Inhibitors Accelerate the Conversion of mouse iPS Cells into Cancer Stem Cells in the Tumor Microenvironment

Cancer stem cells (CSCs) are a class of cancer cells characterized by self-renewal, differentiation and tumorigenic potential. We previously established a model of CSCs by culturing mouse induced pluripotent stem cells (miPSCs) for four weeks in the presence of a conditioned medium (CM) of cancer cell lines, which functioned as the tumor microenvironment. Based on this methodology of developing CSCs from miPSCs, we assessed the risk of 110 non-mutagenic chemical compounds, most of which are known as inhibitors of cytoplasmic signaling pathways, as potential carcinogens. We treated miPSCs with each compound for one week in the presence of a CM of Lewis lung carcinoma (LLC) cells. However, one-week period was too short for the CM to convert miPSCs into CSCs. Consequently, PDO325901 (MEK inhibitor), CHIR99021 (GSK-3 beta inhibitor) and Dasatinib (Abl, Src and c-Kit inhibitor) were found to confer miPSCs with the CSC phenotype in one week. The tumor cells that survived exhibited stemness markers, spheroid formation and tumorigenesis in Balb/c nude mice. Hence, we concluded that the three signal inhibitors accelerated the conversion of miPSCs into CSCs. Similarly to our previous study, we found that the PI3K-Akt signaling pathway was upregulated in the CSCs. Herein, we focused on the expression of relative genes after the treatment with these three inhibitors. Our results demonstrated an increased expression of pik3ca, pik3cb, pik3r5 and pik3r1 genes indicating class IA PI3K as the responsible signaling pathway. Hence, AKT phosphorylation was found to be up-regulated in the obtained CSCs. Inhibition of Erk1/2, tyrosine kinase, and/or GSK-3 beta was implied to be involved in the enhancement of the PI3K-AKT signaling pathway in the undifferentiated cells, resulting in the sustained stemness, and subsequent conversion of miPSCs into CSCs in the tumor microenvironment

The ARCH Projects: design and rationale (IAASSG 001)

OBJECTIVE A number of factors limit the effectiveness of current aortic arch studies in assessing optimal neuroprotection strategies, including insufficient patient numbers, heterogenous definitions of clinical variables, multiple technical strategies, inadequate reporting of surgical outcomes and a lack of collaborative effort. We have formed an international coalition of centres to provide more robust investigations into this topic. METHODS High-volume aortic arch centres were identified from the literature and contacted for recruitment. A Research Steering Committee of expert arch surgeons was convened to oversee the direction of the research. RESULTS The International Aortic Arch Surgery Study Group has been formed by 41 arch surgeons from 10 countries to better evaluate patient outcomes after aortic arch surgery. Several projects, including the establishment of a multi-institutional retrospective database, randomized controlled trials and a prospectively collected database, are currently underway. CONCLUSIONS Such a collaborative effort will herald a turning point in the surgical management of aortic arch pathologies and will provide better powered analyses to assess the impact of varying surgical techniques on mortality and morbidity, identify predictors for neurological and operative risk, formulate and validate risk predictor models and review long-term survival outcomes and quality-of-life after arch surger

Co-occurrence of Point Mutations in the Voltage-Gated Sodium Channel of Pyrethroid-Resistant Aedes aegypti Populations in Myanmar

Background:Single amino acid substitutions in the voltage-gated sodium channel associated with pyrethroid resistance constitute one of the main causative factors of knockdown resistance in insects. The kdr gene has been observed in several mosquito species; however, point mutations in the para gene of Aedes aegypti populations in Myanmar have not been fully characterized. The aim of the present study was to determine the types and frequencies of mutations in the para gene of Aedes aegypti collected from used tires in Yangon City, Myanmar.Methodology/Principal Findings:We determined high pyrethroid resistance in Aedes aegypti larvae at all collection sites in Yangon City, by using a simplified knockdown bioassay. We showed that V1016G and S989P mutations were widely distributed, with high frequencies (84.4% and 78.8%, respectively). By contrast, we were unable to detect I1011M (or I1011V) or L1014F mutations. F1534C mutations were also widely distributed, but with a lower frequency than the V1016G mutation (21.2%). High percentage of co-occurrence of the homozygous V1016G/S989P mutations was detected (65.7%). Additionally, co-occurrence of homozygous V1016G/F1534C mutations (2.9%) and homozygous V1016G/F1534C/S989P mutations (0.98%) were detected in the present study.Conclusions/Significance:Pyrethroid insecticides were first used for malaria control in 1992, and have since been constantly used in Myanmar. This intensive use may explain the strong selection pressure toward Aedes aegypti, because this mosquito is generally a domestic and endophagic species with a preference for indoor breeding. Extensive use of DDT for malaria control before the use of this chemical was banned may also explain the development of pyrethroid resistance in Aedes aegypti

Foreign Language Learning Myanmar Students' Awareness level of Vocabulary Learning Strategies and its Contribution to their Vocabulary Size

Learning strategies namely language, grammar, and vocabulary have received much attention in the studies since they can provide learner's autonomy and effective teaching-learning community. Language learners' vocabulary size determines their command language. Improving the vocabulary size is a long and complicated process for both teachers and learners. The present study attempts to revel the vocabulary learning strategies awareness level of foreign language learning students and its impact on their vocabulary size. In order to investigate the variables, 100 undergraduate students learning foreign languages in a Mandalay based University are chosen based on one-step cluster sampling. The data is collected by employing vocabulary learning strategies developed by Schmitt (2000) to find out awareness level and www.areal.com for investigating students' vocabulary size. 44 percent of all strategies are aware by the students. Memory and Social strategies are the most well-known strategies among learners and Metacognitive strategies are the least ones. There is no much difference is awareness level of discovery and consolidation strategies. The average vocabulary size of the respondent is around 2200. The participants are divided into a controlled group and an experimental group. The unknown and least aware vocabulary learning strategies are introduced to the experimental one. The improvement of vocabulary size (about 4000) is resulted in the experiment group after 3 month training on vocabulary learning strategies. It is recommended that teachers should introduce vocabulary learning strategies depending to the students' learning preferences. Further studies should be carried out the correlation between vocabulary learning strategies and learners' variable like, gender, age, and English as a specific language. The limitations of this study are difficult in introducing certain strategies since the vocabulary exercises in the prescribed course book for learners do not provide them to employ, complicated data collocation for vocabulary size, researcher's interference in data collocation for vocabulary learning strategies awareness level and students' unfamiliarity on vocabulary learning strategies

2-(4-Butoxyphenyl)-N-hydroxyacetamide : An Efficient Preadsorber for Dye-Sensitized Solar Cells

The effect of chemical modification of mesoporous TiO2 electrodes by 2-(4-butoxyphenyl)-N-hydroxyacetamide (BPHA) before dye adsorption is investigated in dye-sensitized solar cells (DSCs). Two organic dyes, LEG4 and Dyenamo blue, were used in combination with the cobalt (II/III) tris(bipyridine) redox couple. The photovoltaic performance of the DSCs is clearly enhanced by BPHA. Preadsorption of mesoporous TiO2 electrodes with BPHA lowered the amount of adsorbed dye but improved the shortcircuit current densities and the power conversion efficiencies by 10-20%, while keeping the open-circuit potential essentially unaffected. Notably, BPHA improved the LEG4 performance, whereas it has been reported for this dye that chenodeoxycholic acid as a coadsorbent lowers solar cell efficiency. Faster dye regeneration was found to be one reason for improved performance, but improved electron injection efficiency may also contribute to the favorable effect of BPHA

Aortic root and total arch replacement with frozen elephant trunk procedure, using a Thoraflex Hybrid Graft

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