112 research outputs found

    Convolutional neural network in the classification of COVID-19

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    Covid-19 spread out rapidly around the world, forcing many countries to full shutdown, and economical and social consequences. Resulting in rapid need for new and effective methods to deal with this crisis and control it. X-ray lung images is considered one of the most effective and safe method for diagnosing Covid-19, since it could provide solid proof of the existing of the disease, and it has limited effect on the health of the human comparing with other radiography methods. In this proposed work, CNN model is designed and trained to classify Covid-19 X-ray images, by using the COVID-19 Radiography Database, which is published and available online. This database is collected by researchers and experts from various universities around the world. The database contains total of 15153 lung x-ray images, divided into three classes. The classification classes are: Normal, Covid-19, and Viral Pneumonia. The model is trained and tested on publicly available dataset. The dataset is divided into three parts: training, validation, and testing datasets. The model is evaluated based on the three of these datasets. Totally, the evaluation metrics include Accuracy, F1-score, Area Under Curve (AUC), Precision, and Recall, with values of greater than 98% for all of the evaluation metrics. Comparing the results with state of arts publications, which used the same dataset, the proposed method outperformed the state of arts publications depending on the evaluation metrics. The number of the trainable parameters in the proposed CNN model is about 25.4 millions

    Susceptibility of Aphidius nigripes (Hym.: Aphididae) adults to entomopathogen Lecanicillium muscarium (Deut.: Moniliales)

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    Susceptibility of Aphidius nigripes Ashmead adults to entomopathogen Lecanicillium muscarium (Petch) Zare & Gams was evaluated with different inoculation methods. Fungus concentrations including 104, 105, 106, 107, 108 spores/ml and control (distilled water with 0/04% triton x-100) were applied by spraying or dipping method on males, females and pupa of parasitoid and mortality was counted daily during 8 days. Both A. nigripes males and females were infected by L. muscarium concentrations. Minimum mortality was observed in 104 spores/ml treatment on the males and females after 8 days. Positive correlation was observed between concentrations and parasitoid mortality. Direct infection method with 108 spores/ml showed the maximum mortality of 97/9% and 100% for females and males, respectively. Estimated LC50 for females was approximately three times more than that of males. LT50 for each concentration indicated more susceptibility of males than the females. Adult wasps were also infected by fungus spores of inoculated plants; however, the mortality of parasitoid was less than that of direct infection (sprayed on adults). Estimated LC50 and LT50 were also greater than those obtained by direct infection of adults. Mummified aphids were infected by L. muscarium, however, the development of fungus mycelium was observed on mummies, and the mortality of parasitoid pupae within mummies was significantly low. A few parasitoids emerged from infected mummies suffered mortality. Further results demonstrated that the adult infection had come in touch with the infected mummies

    Self-healing of dense asphalt concrete by two different approaches: electromagnetic induction and infrared radiation

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    Self-healing of cracks in asphalt mixtures is a phenomenon that can be accelerated by reducing the viscosity of bitumen as it increases the capillarity flow through the cracks. One method to achieve this is by increasing temperature, which also produces a thermal expansion that contributes to the circulation of the bitumen through cracks. In the present paper, the healing performance of asphalt mixture heated using infrared heating to simulate the natural solar radiation, and induction heating, a new method to increase the temperature of asphalt pavements, were compared in terms of time and healing temperature. Healing was defined as the relationship between the 3-point bending strength of an asphalt beam before and after healing. The results show that both methods reach similar and satisfactory healing ratios at around 90 %. However, induction heating is more energy efficient because the effect is concentrated on the binder, instead of heating the whole mix. This can be translated into much shorter heating times to reach the same healing level. Finally, an optimum radiation energy was found, after which higher amounts of infrared radiation damage the properties of the healed material

    Characterisation of a multi-channel multiplexed EMG recording system: towards realising variable electrode configurations

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    First steps towards osseointegrated myoelec-trically-controlled prostheses: Bone anchor conduit conveys EMG signals from implanted electrodes [1]. In vivo selection of electrode configurations would improve signal-to-noise ratio (SNR) of EMG recordings [2]; optimal electrode config-urations are not known before implantation. The CAPITel system: Control of Active Prostheses using Implant-able Telemetry [3,4]. Implantable EMG amplifier with a novel multi-plexed frontend. In vivo selection of monopolar, bipolar or tripolar configurations. Designed using commercially available com-ponents for use in animal models. After further research design will be imple-mented as an ASIC

    Assessing quality of healthcare service by the SERVQUAL model: A case study of a field hospital

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    Aims: Identifying quality gap of services provided by hospital lead to preparing improvement projects and programs. This study intends to determine the quality gap in healthcare services provided by Shahid Elmi Field Hospital from the view point of Patients. Methods: In this cross-sectional study, 100 patients admitted to the hospital in 2011 were selected randomly for the study. The data gathered through SERVQUAL Standard Questioner. The content validity and reliability was confirmed by specialist opinions and Cronbach's alpha coefficient, respectively. Data analysis was conducted using descriptive statistics and two-sample t, Pearson correlation and ANOVA tests, using SPSS version 18. Results: According to the patients' views, there is a positive quality gap in delivered services. The highest mean score of the negative and positive quality gap were related to Responsiveness (-0.02) and access (0.035) respectively. There was a significant relation between the frequency of referral and the quality empathy (p=0.05). Conclusion: According to the results, the delivered services of the studied Field hospital is higher than the expectations of patients. It is recommended that processes related to delivery of services, in all dimensions of services' quality particularly responsiveness and assurance, should be identified and reengineered

    A Review of Artificial Intelligence in Breast Imaging

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    With the increasing dominance of artificial intelligence (AI) techniques, the important prospects for their application have extended to various medical fields, including domains such as in vitro diagnosis, intelligent rehabilitation, medical imaging, and prognosis. Breast cancer is a common malignancy that critically affects women’s physical and mental health. Early breast cancer screening—through mammography, ultrasound, or magnetic resonance imaging (MRI)—can substantially improve the prognosis for breast cancer patients. AI applications have shown excellent performance in various image recognition tasks, and their use in breast cancer screening has been explored in numerous studies. This paper introduces relevant AI techniques and their applications in the field of medical imaging of the breast (mammography and ultrasound), specifically in terms of identifying, segmenting, and classifying lesions; assessing breast cancer risk; and improving image quality. Focusing on medical imaging for breast cancer, this paper also reviews related challenges and prospects for AI

    Cancer Patterns in Quetta (1998-1999)

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    Introduction: Quetta, the capital of Baluchistan, is located at latitude 30,25; longitude 67.00. It has a population of 759,245; 425,474 males (56%) and 333,771 females (44%); Census 1998. The majority of residents are Persian or Baluchi speaking Baluchs. Methodology: The cancer cases from Quetta reported to the Karachi Cancer Registry were reviewed. The data included cases from the Aga Khan University Hospital (AKUH), Pathology Department (Quetta collection point) and health care facilities in Karachi. The residents of Baluchistan were ascertained and cancer cases residents of Quetta identified with the help of recorded addresses and retraceable telephone numbers. Results: During a 2-year period, 1st January 1998 to 31st December 1999 the Karachi Cancer Registry received 1077 cancer notifications from Quetta. Approximately half the cases were registered from the AKUH Quetta collection point. Others were the referral patterns in Karachi. The age-standardized incidence rate (ASR) of cancer, all sites (1998-99) was 137.0 for males and 92.8/100,000 for females. The commonest cancer in the males and females was cancer of the esophagus (lCD­10 categories C15; males- ASR 25.5, 17.2 %; females- ASR 23.4, 23.1%). One of the highest in the world, for both genders. Incidence of cancer breast in the females (lCD-10 categories C50; ASR 11.8, 13.3%) was low, Conclusion: The cancer data from Quetta is quite distinct from the cancer pattern of Karachi. It represents only a part of the cancer burden of Quetta; nonetheless it gives a glimpse into the cancer profile of Baluchistan. The high incidence of esophageal cancer indicates an extension of the geographical limits of the esophageal cancer belt

    The use of a bone-anchored device as a hard-wired conduit for transmitting EMG signals from implanted muscle electrodes.

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    The use of a bone-anchored device to transmit electrical signals from internalized muscle electrodes was studied in a sheep model. The bone-anchored device was used as a conduit for the passage of a wire connecting an internal epimysial electrode to an external signal-recording device. The bone-anchored device was inserted into an intact tibia and the electrode attached to the adjacent M. peroneus tertius. "Physiological" signals with low signal-to-noise ratios were successfully obtained over a 12-week period by walking the sheep on a treadmill. Reliable transmission of multiple muscle signals across the skin barrier is essential for providing intuitive, biomimetic upper limb prostheses. This technology has the potential to provide a better functional and reliable solution for upper limb amputee rehabilitation: attachment and control

    Myoelectric Signal Transmission from Implanted Epimysial Electrodes Using a Bone-Anchor as a Conduit

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    Introduction Current Upper-limb myoelectric prostheses rely on only 2 control signals from surface electrodes, placed over antagonistic muscles in the amputation stump, for limb control. While this has benefits over the traditional body-powered control, there are disadvantages; electrode lift-off, impedance variation, cross-talk, reliability, and limitations in intuitive control. To address these problems, electrodes can be implanted directly on individual muscles responsible for specific actions. Not only does this address skin-related issues, it reduces cross-talk and greatly increases the number of control channels for multi degrees of freedom intuitive control. Bone-anchored devices can be used to overcome problems with prosthetic attachment and additionally used to transfer control signals from these implantable electrodes to the prosthesis. [1] In above-elbow amputees, targeted muscle reinnervation (TMR) enables more signal generation by redirecting nerves previously controlling the amputated muscles in the forearm, to surrogate muscles in the torso (e.g. pectoralis major). [2] We describe in vivo model using implantable electrodes to record myoelectric signals (MES) in normal muscles and following TMR, utilizing a bone-anchor as a conduit to carry signals across the skin barrier. Materials and Methods An in vivo n=6 ovine model was used. A bone-anchor was placed trans-tibially and bipolar electrodes sutured to M. Peroneus Tertius (PT). In a further n=1, motor nerve to PT was divided and coapted with a motor branch from peroneal nerve. MES were recorded over a 12-week period. Functional recovery in the TMR model was assessed by MES and force-plate analysis (FPA). Results In the n=6 group, there was a positive correlation between signal to noise ratio (SNR) and time since implantation (p < 0.005), with a mean SNR of 7 by week 12. In the TMR model, functional recovery was observed after 6 weeks. Difference between legs returned to normal (pre-op: left 4.7 N/kg, right 4.8 N/kg; 80 days post-op: left 4.1 N/kg, right 4.3 N/kg). Recorded MES from TMR muscle compared favourably with healthy muscle. Conclusions We have demonstrated that a bone-anchor is a reliable and robust conduit for transmitting MES over a period of 12 weeks. The combination of implanted electrodes & direct skeletal fixation offers clear advantages over current systems for prosthetic attachment & control. This system forms the basis of a complete solution for prosthetic rehabilitation, which can also be used in the context of TMR. References 1. Al Ajam et. al., 2013. PMID: 23358938 2. Kuiken et. al., 2004. PMID: 1565863
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