467 research outputs found

    Interleukin 2 restores CD3-zeta chain expression but fails to generate tumour-specific lytic activity in tumour-infiltrating lymphocytes derived from human colorectal hepatic metastases.

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    Metastatic colorectal cancer is usually progressive despite infiltration of the tumours by T lymphocytes, suggesting that these tumour-infiltrating lymphocytes (TILs) are functionally deficient. Recently, TILs from other tumours have been shown to express reduced levels of the T-cell receptor signal-transducing CD3-zeta chain. We were interested to determine whether a similar abnormality existed in TILs from human colorectal hepatic metastasis (CHM) and, if so, whether correcting the abnormality in vitro would restore anti-tumour activity and provide support for the development of immunotherapy for colorectal hepatic metastases. Twelve of 19 TILs from colorectal hepatic metastases were successfully expanded in vitro in high-dose recombinant interleukin 2 (rlL-2) and their specific anti-tumour cytolytic activity was determined. CD3-positive (CD3+) TILs were HLA-Drhigh and CD69high, suggesting that they had been activated by exposure to antigen but expressed low levels of CD25, CD71 and the nuclear proliferation antigen Ki-67. Furthermore, they showed reduced expression of CD3-zeta compared with autologous peripheral blood T cells (PBTs) and failed to proliferate in the absence of high-dose rIL-2. Expansion of TILs in rIL-2 resulted in restoration of CD3-zeta expression and the ability to lyse K562 and Daudi cells but not autologous tumour cells. The absence of autologous tumour-specific cytolytic T-cell (CTL) activity may be due to the poor immunogenicity of colorectal tumour cells, which we found expressed only low levels of MHC I antigens and CD54 and failed to express MHC II antigens or the co-stimulatory molecules CD80, CD86 or CD106. The inability of rIL-2 to generate tumour-specific CTLs despite restoration of CD3-zeta expression and the presence of an intact lytic mechanism suggests that successful immunotherapy may require the development of strategies to increase the immunogenicity of this tumour

    Modeling and Dynamic performance of Energy Storage -Rotary Series Elastic Actuator for Lumbar Support Exoskeleton

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    The assistive exoskeletons are rapidly being developed to collaborate with humans, and the demand for the safety of human-robot interaction has become more crucial. Series elastic actuators (SEAs) have recently been developed in various fields for a variety of possible advantages, such as providing a safe human-robot interaction, reducing the impacts’ effects, and increasing energy efficiency. However, achieving the good dynamic performances of SEAs is still challenging, especially fulfilling the high bandwidth with good compliance. In this rapidly growing research field, the actuation system involving the storage device combined with the rotary series elastic actuator (ES-RSEA) is being investigated to exploit the biomechanical energy while maintaining compliance features. In this article, the modeling and control design of the energy storage rotary series elastic actuator (ES-RSEA) for the lumbar support exoskeleton is proposed, and its dynamic performances are analyzed. The ES-RSEA was designed based on storing the kinetic energy during the lifting tasks and generating assistive torque while maintaining excellent compliant characteristics. The dynamic performances and characteristics of ES-RSEA are presented in terms of force sensitivity, level of compliance, transmission ratio, and bandwidth. Simulation studies indicate that the actuator can provide excellent dynamic performance through its high bandwidth (12.44 Hz) and high force sensitivity. At the same time, it shows excellent compliance and good torque transmissibility in the low-frequency range. A PID controller can achieve high torque tracking performance and good dynamic response with a root-mean-square (RMS) error of 0.1 N.m. This article demonstrates the excellent performance and characteristics of ES-RSEA to guarantee compliance and high response to prevent injury of undesired human movements

    Performance Measure Of Industrial Robotics In Lean Enterprise: A Case Study In Semiconductor Industry

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    Industrial robotics replaced human workers in almost all fields due to their abilities to multitask, flexibility and configurability in any position they involved in. However, implementing industrial robotics is challenging due to their high cost, expert handling, and complexity. The object of this study is to determine the performance measurement using the QCDAC method or (quality, cost, delivery, accountability and continual improvement) then categorized according to lean principles and then identifying seven main areas that the industrial robotics contributes in the semi-conductor company. The performance identification and ranking is done by using Interpretive Structural Modelling (ISM) methodology to identify the most affected performance of the model and to clarify the industrial robotics performance in these areas in which the industrial robotics fit and compatible with the lean enterprise. Human- robot interaction considered to guarantee the workers' safety working alongside industrial robotics. The result of the ISM method shows the performance measure that affects the industrial robotics to support lean enterprise in terms of quality improvement, cost reduction and efficiency

    Spotlight on
 training

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    Training in obstetrics and gynaecology has evolved significantly over the past two decades, offering thrilling opportunities to progress women’s health and, at the same time, presenting various challenges to both trainees and trainers. In this Spotlight, we highlight the changes in training reflected in past issues of The Obstetrician and Gynaecologist (TOG) from 2001 until now, initially with the implementation of the Modernising Medical Careers (MMC) training scheme, moving on to the introduction of new subspecialty training and finally the focus on team learning and non‐technical skills. We now recognise the importance of human factors, self‐reflection, and learning from Serious Incidents Requiring Investigation (SIRI) as an integral part of the development of an obstetrician and gynaecologist. We explore the issues of alternative training opportunities allowing doctors to pursue the Certificate of Eligibility for Specialist Registration (CESR) accreditation as an alternative to Certificate of Completion of Training (CCT). In this Spotlight, we also confront the high attrition (Br J Hosp Med 2017;78(6):334–8) and undermining rates reported by trainees, as well as the increasing physician burnout in our speciality

    P171Elevated free fetal haemoglobin threatens vasculoprotection in the fetal circulation of preeclamptic pregnancy

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    Placental up-regulation of free fetal haemoglobin (fHbF) occurs in preeclamptic (PE) pregnancy. Heme oxygenase-1 (HO-1) is an important vasculoprotective enzyme in the catabolism of the associated heme porphyrin structure. We have previously shown that fHbF negatively influences the vasculoprotective capacity of the fetal circulation. Here we study fHbF levels in the fetal cord blood of pregnancies complicated by PE; a pathology associated with dysregulated fetoplacental vascular tone. We have previously shown that fHbF binds nitric oxide (NO) to elicit elevated vascular resistance in the fetoplacental circulation, using ex vivo human dual placental perfusion and in vitro placental endothelial cell shear stress studies. Furthermore, fHbF causes morphological changes to the fetoplacental endothelium. Here we hypothesise that elevated levels of fHbF in fetal plasma associated with placental pathology contribute to fetoplacental hypertension. Purpose: To evaluate and derive a robust cord blood collection and processing protocol for the accurate measurement of fetal plasma fHbF levels in normal and PE pregnancies. Methods: Fetal venous cord blood was collected by syringe and needle, or Vacutainer method into either EDTA or citrate tubes, within 10 minutes of partum. Plasma recovery occurred immediately, or after 30 minutes, prior to centrifugation at 2000g x 10 min at room temperature. Following evaluation to reduce mechanical haemolysis, newly collected normal & PE plasma (n=13 & 6, respectively) was subjected to ELISAs for HbF and HO-1. Results: Venipuncture collection of cord venous blood taken from the cord-placenta insertion point by Vacutainer system with a 21G needle, into citrate collection tubes with immediate centrifugation prevented mechanical haemolysis. There was no difference in plasma HO-1 between groups (medians = 5.9 & 5.3 ng/mL; normal & PE, respectively; Mann-Whitney). Whilst there was no difference in fHbF between groups (Mann-Whitney), variability was high in the PE group and there were some very high values for fHbF compared to the normal range, whilst fHbF values in the control group were within a tighter lower range (medians & ranges = 45.9 & 0-206 and 118.8 & 29-640 ÎŒg/mL). Conclusion: Fetal plasma HO-1 levels appear stable in preeclamptic fetal plasma, permitting fHbF to remain unchecked in some cases. High pathophysiological levels of fHbF in some cases of PE pregnancies are capable of evoking elevated vascular resistance within the fetoplacental circulation, caused by nitric oxide sequestration and disruption to the endothelium. Further evaluation is require

    Cycle Time Reduction For Coil Setup Process Through Standard Work: Case Study In Ceramic Industry

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    In this study, it found that the cycle time of the setup process in a pressing process is inconsistent. This is due to the absence of proper working instruction and workers perform the setup process in varying working steps. Therefore, a new method of the coil setup was developed and standardized which able to improve the efficiency and reduce the lead time of the process. The excessive steps and non-standardize working procedure of the workers in the coil setup needed to be eliminated and some internal steps should change to internal steps to reduce the cycle time. To achieve the objective of this study, the method used in this study is lean tools and techniques such as Time Measurement Sheet (TMS), Standard Work Combination Table (SWCT), Standard Work Chart (SWC) and Single Minutes Exchange Dies technique (SMED). The finding of this study is a new Standard Operating Procedure (SOP) that able to reduce the cycle time and increase the efficiency of the coil setup. This new SOP will be used for the future reference, and it will proliferate to the other similar operation in the department. Future research should conduct in this direction of examining the working mechanism of the workers by using Maynard’s Operation Sequence Technique (MOST) to get more accurate results and achieve continuous improvement

    Strong and stable photoluminescence from the semiconducting inner tubes within double walled carbon nanotubes

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    This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in APPLIED PHYSICS LETTERS. 94(8):083106 (2009) and may be found at https://doi.org/10.1063/1.3085966 .ArticleAPPLIED PHYSICS LETTERS. 94(8):083106 (2009)journal articl
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