1,864 research outputs found

    Placenta praevia: Preach and perception

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    Placenta praevia is a known obstetric condition that causes complications to mother and fetus. This study was done to evaluate the knowledge of placenta praevia amongst the obstetric patients. A cross sectional study was carried out in Hospital Ipoh, Perak among 323 antenatal and postnatal patients. Socio-demographic parameters (ie age, race, parity, occupation, educational level) and history of placenta praevia were studied in relation to level of knowledge and attitude towards placenta praevia. Twenty (6.2%) from 323 women had current or past history of placenta praevia. Three had history of placenta praevia while 17 had current placenta praevia with prevalence of 5.3%. The mean score of knowledge achieved by patients was 11.8 which indicated overall poor knowledge. Occupation, level of education and history of placenta praevia were found to have a relationship with level of knowledge regarding placenta praevia in all obstetric patients. There was a significant relationship between attitude of patients with current and history of placenta praevia to level of knowledge regarding placenta praevia. (p=0.037, <0.05). In conclusion, the knowledge and attitude towards placenta praevia among obstetric patients in Hospital Ipoh was better in those who had higher education status, white-collar occupation and currently pregnant with placenta praevi

    Mirizzi syndrome associated with hepatic artery pseudoaneurysm: a case report.

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    INTRODUCTION: This is the first case report of Mirizzi syndrome associated with hepatic artery pseudoaneurysm. CASE PRESENTATION: A 54-year-old man presented with painful obstructive jaundice and weight loss. Computed tomography showed a hilar mass in the liver. Following an episode of haemobilia, angiography demonstrated a pseudoaneurysm of a branch of the right hepatic artery that was embolised. At surgery, a gallstone causing Mirizzi type II syndrome was found to be responsible for the biliary obstruction and a necrotic inflammatory mass and haematoma were found to be extending into the liver. The mass was debrided and drained, the obstructing stones removed and the bile duct drained with a t-tube. The patient made a full recovery. CONCLUSION: This case highlights another situation where there may be difficulty in differentiating Mirizzi syndrome from biliary tract cancer.Published versio

    Interplay between ER stress and hypoxia pathways in chondrocytes

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    Poster Presentation - Theme 3: Development & stem cellsInterplay between stress signals can regulate cell fate. Potential connections are emerging between hypoxia and ER homeostasis. It is well established that presence of mis-folded protein in the endoplasmic reticulum (ER) triggers the unfolded protein response (UPR) as part of the ER-stress signal for cell survival. Under low oxygen tension or hypoxia, the cell activates the hypoxic stress signal via the activation of Hif genes, and utilize components of the ER-stress pathways for cell survival and adaptation to the stress condition. However, whether activation of ER stress by accumulation of mis-folded protein has a direct relationship with activation of hypoxia and components ...postprin

    Three-waveform bidirectional pumping of single electrons with a silicon quantum dot

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    Semiconductor-based quantum dot single-electron pumps are currently the most promising candidates for the direct realization of the emerging quantum standard of the ampere in the International System of Units. Here, we discuss a silicon quantum dot single-electron pump with radio frequency control over the transparencies of entrance and exit barriers as well as the dot potential. We show that our driving protocol leads to robust bidirectional pumping: one can conveniently reverse the direction of the quantized current by changing only the phase shift of one driving waveform with respect to the others. We anticipate that this pumping technique may be used in the future to perform error counting experiments by pumping the electrons into and out of a reservoir island monitored by a charge sensor.The financial support from the Centre of Excellence in Computational Nanoscience (project 284621 and 251748) by the Academy of Finland (Grant Nos 251748, 135794, 272806, and 276528), the Australian Research Council (Grant Nos DP120104710 and DP160104923), Jenny and Antti Wihuri Foundation, The Finnish Cultural Foundation, and the Australian National Fabrication Facility are acknowledged. A. R. thanks the University of New South Wales Early Career Research Grant scheme for financial support. We acknowledge the provision of facilities and technical support by Aalto University at Micronova Nanofabrication Centre

    Assessment of the genetic variation of Malaysian durian varieties using inter-simple sequence repeat markers and chloroplast DNA sequences

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    To date, 124 durian varieties have been registered with the Malaysian Department of Agriculture based on phenotypic characteristics. However, the levels and patterns of genetic variation among the varieties are still unknown. In this study, the leaves of 27 durian varieties were sampled from four durian orchards in Universiti Putra Malaysia, namely Bukit Ekspo, Putra Mart, Ladang Puchong and Ladang 5. Twenty five inter-simple sequence repeat (ISSR) primers were tested for PCR amplification on DNA samples. Twelve ISSR primers amplified 133 clear and reproducible DNA fragments and 122 (91.73%) were polymorphic, indicating a high level of genetic variation among these durian varieties. Primers flanking four chloroplast DNA (cpDNA) regions (trnL-trnF, atpB-rbcL and trnH-psbA intergenic spacers as well as the partial matK gene) were tested for PCR amplification. Two cpDNA regions (trnL-trnF and matK) were successfully amplified, but showed no variation in their DNA sequences, even when additional samples from Vietnam were included. The findings in this preliminary study lay a foundation for more comprehensive future studies on the genetic variation among durian varieties

    An Overview of Methods using Reduced-Ordered Transformation Matrices for Fault-Tolerant Control of 5-phase Machines with an Open Phase

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    This paper studies control strategies using modified transformation matrices when five-phase machines operate in oneopen-phase faults. The basic idea of these methods is to maintain the rotating field under asymmetrical conditions as the same as in healthy condition by determining new transformation matrices. The dimension of the new matrices is equal to the number of remaining healthy phases in post-fault conditions. There have been different ways to determine the new transformation matrices applied for different types of five-phase machines in recent decades. In this study, an overview and analyses on these methods will be presented. In addition, advantages and drawbacks of these control strategies are clarified by numerical results

    Eliminations of Low-frequency Current Harmonics for Five-phase Open-end Winding Non-sinusoidal Machine Drives applying Neural Networks

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    This study aims at eliminating unwanted harmonics in current control of a five-phase non-sinusoidal permanent magnet synchronous machine (PMSM) in an open-end winding configuration. The machine is supplied by two voltage source inverters (VSIs) using a single DC-bus voltage. High-frequency harmonics, caused by the zero-sequence current with the inverter switching frequency, have been significantly reduced by using a proper pulse width modulation (PWM) strategy. Meanwhile, low-frequency current harmonics are generated by unwanted harmonics of the back electromotive force (back-EMF) and by the inverter nonlinearity. In this study, the low-frequency current harmonics are nullified by simple adaptive linear neural networks (ADALINEs) in rotor reference frames combined with the back-EMF compensation. As a result, the quality of current control is improved. The effectiveness of the proposed strategies is verified by numerical resultsThis work has been achieved within the framework of CE2I project. CE2I is co-financed by European Union with the financial support of European Regional Development Fund (ERDF), French State and the French Region of Hauts-de-France

    Fault-tolerant Control for Non-sinusoidal Multiphase Drives with Minimum Torque Ripple

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    For non-sinusoidal electromotive force (NS-EMF) multiphase machines, this paper proposes a new strategy and control scheme to guarantee smooth torque under an open-phase fault. Notably, the conventional proportional-integral (PI) controllers implemented for vector control in healthy mode can be used in the faulty mode. The strategy is based on reduced-order transformations while the control scheme applies a simple artificial intelligence algorithm using a specific online-trained Adaptive Linear Neuron (ADALINE). Indeed, the inputs of ADALINE require the knowledge of rotor position and NS-EMF harmonic rank to optimize the learning time. The proposed strategy and control scheme are tested on a seven-phase machine with a strong Total Harmonic Distortion (THD) of NS-EMFs, containing numerous harmonics Hk (THD=38% with 100% H1, 32.3% H3, 9.4% H7, 12.5% H9, 10.3% H11). Numerical and experimental results are presented in this paper. This paper is accompanied by a video demonstrating the experimental results.This research was funded by CE2I project. CE2I is co-financed by European Union with 573 the financial support of European Regional Development Fund (ERDF), French State and the French 574 Region of Hauts-de-France
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