Finding Structural Information of RF Power Amplifiers using an Orthogonal Non-Parametric Kernel Smoothing Estimator

A non-parametric technique for modeling the behavior of power amplifiers is presented. The proposed technique relies on the principles of density estimation using the kernel method and is suited for use in power amplifier modeling. The proposed methodology transforms the input domain into an orthogonal memory domain. In this domain, non-parametric static functions are discovered using the kernel estimator. These orthogonal, non-parametric functions can be fitted with any desired mathematical structure, thus facilitating its implementation. Furthermore, due to the orthogonality, the non-parametric functions can be analyzed and discarded individually, which simplifies pruning basis functions and provides a tradeoff between complexity and performance. The results show that the methodology can be employed to model power amplifiers, therein yielding error performance similar to state-of-the-art parametric models. Furthermore, a parameter-efficient model structure with 6 coefficients was derived for a Doherty power amplifier, therein significantly reducing the deployment's computational complexity. Finally, the methodology can also be well exploited in digital linearization techniques.Comment: Matlab sample code (15 MB): https://dl.dropboxusercontent.com/u/106958743/SampleMatlabKernel.zi

Yield of Muscle Biopsy in Patients with Findings of Myopathy on Electrodiagnostic Testing

Background: The evaluation of neuromuscular diseases includes detailed clinical assessment, blood testing, electrodiagnostic studies (EDS), biopsy, and genetic tests. EDS alone cannot provide a specific diagnosis. Further testing in the form of genetic tests or muscle biopsy (MB) is required. Objective The objective of the study is to evaluate the yield of MB in patients with findings of myopathy on electrodiagnostic testing and assess the factors affecting an abnormal biopsy outcome. Methods: Electromyography (EMG)/nerve conduction studies (NCS) performed for suspected myopathy over 5 years from 2011 to 2016, at the neurophysiology department of a tertiary care center in Pakistan, were reviewed. Based on inclusion criteria, records of 58 patients were retrospectively reviewed. Results: After an EMG/NCS diagnosis of myopathy, the frequency of MB testing was only 10.1%. The median age of patients was 26.5 years. The clinically suspected diagnosis was categorized into hereditary myopathy (n = 15, 25.9%) and acquired myopathy (n = 18, 31%). The positive predictive value of EMG is 77.2%. Twenty-eight (48.2%) patients had abnormal MB whereas 20 (34.4%) revealed normal findings. Factors significantly influencing an abnormal outcome of biopsy included moderate-to-severe elevation of creatine kinase (\u3e2,000 U/L),presence of denervation changes, and severe myopathy on EMG. Conclusion: Even though the overall yield of MB testing may not be very high in our setting due to the unavailability of special techniques and expertise, certain factors can help to improve the diagnostic yield. Clinicians should encourage MB testing, especially in cases with strong clinical, laboratory and electrodiagnostic suspicion, and absence of genetic testing for suspected myopathy

Nasal encephaloceles presenting at later ages: experience of otorhinolaryngology department at a tertiary care center in Karachi, Pakistan

Encephaloceles are anomalous herniations of the meninges, with or without brain matter. Globally the incidence of encephalocele is about 1 per 35,000 births, but it is more frequently reported in Southeast Asia. As the defect is more pertinent to embryological development, an encephalocele is a more common entity in an infant with a mean age of presentation ranging between 15.5 and 21 months; making an encephalocele presenting for the first time in a relatively, older individual a rare occurrence. Consequently a surgeon might not consider an encephalocele among his differentials. Here we present a series of encephaloceles that presented at a later than usual age as nasal masses to the otorhinolaryngology department of our hospital, and recommend that the differential of encephalocele be entertained for nasal masses as proceeding with routine procedures may result in potentially lethal complications

Infantile haemangioendothelioma of the parotid gland: Case report and review of literature

Haemangioendotheliomas (HAE), although rare but are the most common parotid gland tumours in children. We report a 4-month-old girl who presented with a progressively enlarging right sided facial swelling overlying the angle of the mandible. An Ultrasound of the lesion and a computed tomography (CT) scan of the head and neck was carried out which revealed a large lesion within the right parotid gland. CT scan further demonstrated a direct communication with the right external carotid artery and external jugular vein. Considering the clinical course and radiological findings, there was sufficient evidence to avoid any invasive testing. Due to the self-limiting nature of the disease, patient was managed expectantly

Risk Factors of Blood Transfusion during Caesarean Delivery in Rural Area of Sindh

Introduction: Hemorrhage is a leading cause of maternal deaths; particularly in developing countries. Bleeding in pregnant ladies is an indication of blood transfusion with all its attended risk. Objective: This study was conducted to identify the factors necessitate blood transfusion during cesarean section. Methodology: A total number of 2855 of pregnant women scheduled for emergency cesarean section or elective cesarean section at Bhurgri Hospital, rural area of Sindh, between July 2014 and December 2017. Participant were followed from the date of admission to the date of discharge and then for two weeks. Preoperative Hb level and the need for blood transfusion, clinical experience of obstetrician, indication for caesarean section, primary or repeat caesarean section and status of HBsAg/HCV were assessed. Results: A total of the numbers of 4823 patients had deliveries from July-2014 to Dec-2017.Among them, 2855 patients underwent cesarean delivery, the ratio of cesarean section was recorded as 59.19%. All pregnant women who underwent cesarean delivery selected for our study. The mean age of the women who had surgery was 26 years. Conclusion: Preoperative anemia, increasing parity, severe blood loss at surgery and status of HBs/HCV significantly contributes to require for blood transfusion in pregnant women undergoing a surgery (cesarean section). Keywords: Caesarean section, Blood product transfusion, Risk factors, Anemia, HBs, HCV

Brain Death Islamic Perspective

Western world has well defined criteria for declaring the patient brain dead and discontinuation of life support treatment. However in the Muslim world these methods and practices are seen with skepticism as to their acceptance from Islamic and Sharia point op view, which in fact is incorrect and is due to lack of knowledge and absence of Institutional guidelines on this matter. Islamic law permits the withdrawal of futile treatment, including life support, from brain dead patients allowing death to take its natural course. “Do not resuscitate” is permitted in Islamic law in brain dead patients. Euthenesia is however unacceptable in Islam. Although debate continues about the details of brain death criteria within Islamic scholars, brain death is accepted as true death by the majority of Mulim scholars and there is concensus on discontinuation of life support treatment in brain dead patients

Deep Reinforcement Learning for Backscatter Communications: Augmenting Intelligence in Future Internet of Things

Backscatter communication (BC) technology offers sustainable solutions for next-generation Internet-of-Things (IoT) networks, where devices can transmit data by reflecting and adjusting incident radio frequency signals. In parallel to BC, deep reinforcement learning (DRL) has recently emerged as a promising tool to augment intelligence and optimize low-powered IoT devices. This article commences by elucidating the foundational principles underpinning BC systems, subsequently delving into the diverse array of DRL techniques and their respective practical implementations. Subsequently, it investigates potential domains and presents recent advancements in the realm of DRL-BC systems. A use case of RIS-aided non-orthogonal multiple access BC systems leveraging DRL is meticulously examined to highlight its potential. Lastly, this study identifies and investigates salient challenges and proffers prospective avenues for future research endeavors.Comment: 7,

Prediction of signal attenuation due to duststorms using mie scattering

The present trend in radio design calls for the use of frequencies above 40 GHz for short links carrying wide-band digital communication signals. In order to utilize the new frequency band efficiently, signal attenuation studies due to duststorms is needed urgently for desert areas. This paper presents a mathematical model which has been developed to predict the signal attenuation due to duststorm. The proposed model enables the convenient calculation of the signal path attenuation based on Mie solution of Maxwell's equations for the scattering of electromagnetic wave by dust particles. The predicted values from the proposed mathematical model are compared with the measured values observed in Saudi Arabia and Sudan and show relatively close agreement

Green Synthesis of Nickel Oxide Nanoparticles using Populus ciliata Leaves Extract and their Potential Antibacterial Applications

Green synthesis of nanoparticles has received a lot of attention from scientists globally because it is eco-friendly, relatively rapid, and a cost-effective  method. This work presents a method for the green synthesis of nickel oxide nanoparticles (NiO-NPs) using leaf extracts of Populus ciliata as a reducing  and stabilising agent. The synthesised NiO-NPs were characterised by ultravioletvisible spectroscopy, Fourier transform infrared spectroscopy, powder  X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. It was found that the synthesised NiO-NPs shapes varied, were  highly crystalline, and had a face-centred cubic geometry. The calculated crystallite size of the synthesised nanoparticles was 44 nm. Moreover, the  antibacterial activity of the synthesised NiO-NPs was also conducted against Gram-positive bacteria (Bacillus subtilis, Bacillus licheniformis) and Gram-  negative bacteria (Escherichia coli and Klebsiella pneumoniae). Bacillus subtillus showed a maximum inhibition zone of 28.1±1.6 mm, whereas Klebsiella  pneumonia showed a minimum inhibition zone of 9.2±0.5 mm. It was also found that the antibacterial activity increased with an increase in the  concentration of NiO-NPs

Bacteriological investigation of ground water sources in selected urban areas of district Mardan, Khyber Pakhtunkhwa, Pakistan

Microbial contamination of ground water sources is a common problem in all the big cities, which endangers health and impairs quality of living . To assess this, 39 water samples were collected from highly populated 13 union councils from the urban area of district Mardan. Faecal coliform and Escherichia coli were investigated both qualitatively and quantitatively. Qualitative study showed that faecal coliform was found in 90% samples and E. coli in 56% samples. Quantitatively, faecal coliform most probable number (MPN) was ranging from 1601 to 2400 for about 28% samples, followed by 551 to 1600 and 201 to 550 for 20% samples each, 40 to 200 for 18% samples and less than 40 for about 13% samples. The major cause of the bacteriological contamination was found to be the extent of susceptibility of the water sources to intrusions from the nearest contamination source.Keywords: Mardan, urban area, microbial contamination, faecal coliform, ground water, Escherichia col