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This study reports on a highly miniaturised polarisation selective surface (PSS) for dual-band Wi-Fi and WLAN applications. The proposed unit cell consists of two independently tuneable square loops. The outer loop is split with a gap of 0.2 mm to introduce polarisation selectivity and miniaturisation for lower-frequency band of 2.5 GHz. The inner square loop is inductively loaded with arms to suppress 5.45 GHz frequency band. These configurations have resulted in a unit element size of λ ∘ / 14 at 2.5 GHz, which is not presented before to the best of the authors' knowledge. A wide rejection bandwidth ( − 10 dB ) of more than 600 and 1180 MHz is obtained around 2.5 and 5.45 GHz, respectively. Furthermore, the proposed PSS exhibits an excellent polarisation selective characteristic by generating two stopbands at 2.5 and 5.45 GHz when illuminated by horizontal (TM) incident waves, whereas vertically (TE) polarised incident waves result in the generation of passbands for these two frequencies. Numerical validation through equivalent circuit modelling of the proposed PSS has also been carried out. A finite prototype containing 31 × 33 elements is fabricated and tested. The measured results demonstrated that the PSS has excellent potential for applications that employ polarisation separators and wave generators.

An eight element, compact Ultra Wideband- Multiple Input Multiple Output (UWB-MIMO) antenna capable of providing high data rates for future Fifth Generation (5G) terminal equipments along with the provision of necessary bandwidth for Third Generation (3G) and Fourth Generation (4G) communications that accomplishes band rejection from 4.85 to 6.35 GHz by deploying a Inductor Capacitor (LC) stub on the ground plane is presented. The incorporated stub also provides flexibility to reject any selected band as well as bandwidth control. The orthogonal placement of the printed monopoles permits polarization diversity and provides high isolation. In the proposed eight element UWB-MIMO/diversity antenna, monopole pair 3-4 are 1800 mirrored transform of monopole pair 1-2 which lie on the opposite corners of a planar 50 × 50 mm2 substrate. Four additional monopoles are then placed perpendicularly to the same board leading to a total size of 50 × 50 × 25 mm3 only. The simulated results are validated by comparing the measurements of a fabricated prototype. It was concluded that the design meets the target specifications over the entire bandwidth of 2 to 12 GHz with a reflection coefficient better than -10 dB (except the rejected band), isolation more than 17 dB, low envelope correlation, low gain variation, stable radiation pattern, and strong rejection of the signals in the Wireless Local Area Network (WLAN) band. Overall, compact and reduced complexity of the proposed eight element architecture, strengthens its practical viability for the diversity applications in future 5G terminal equipments amongst other MIMO antennas designs present in the literature.

Bladder cancers rarely are non-urothelial in origin. We present here, possibly the youngest case of a 35-year-old White female presenting with shortness of breath. She was found to have a malignant pleural effusion with unknown primary, eventually confirmed with genetic testing as metastatic adenocarcinoma of the urinary bladder with brain and lung metastasis. She was scheduled for palliative chemotherapy, however, passed away before it could be started. We highlight this rare case because of its unique presentation. Owing to similarity in receptors between adenocarcinoma and enteric cancer, similar chemotherapy regimens may be used for both. Unfortunately, treatment of metastatic disease remains highly controversial and needs to be studied further if there is an actual survival benefit to this or not.

Purpose: To use clinical audit in improving the outcomes of manual small incision cataract surgery technique Study Design: Clinical audit. Place and Duration: Layton Rehmatullah Benevolent Trust Eye hospital Karachi, from September 2019 to December 2019. Methods: Two hundred patients who had undergone Manual Small Incision Cataract surgery were selected. Cases with traumatic cataract, weak zonules, pseudoexfoliation, and more than 1 diopter difference in keratometric readings, corneal and retinal pathologies were excluded. Surgical complications and visual outcomes were recorded on the 7th postoperative day. Refractive data was recorded from subjective refraction. Data was analyzed by University Hospital Bristol formula. Standards were set using international literature. Deficiencies were noted and technique was modified to improve the outcome. The audit was repeated after 2 months to see whether modifications had improved the outcome. Results: In the first audit, posterior capsular rupture rate was 1%, corrected visual acuity of 6/12 or better was achieved in 85.36% and surgically induced cylinder of less than 2 DC was achieved in 75.60% of the patients. In the second audit all standards were achieved. Posterior capsular rupture did not occur. Corrected visual acuity of 6/12 or better was achieved in 90.50% and induced cylinder of less than 2 DC was achieved in 87.05% of the patients. Conclusion: Clinical audit of the surgical procedures is a good technique in improving the outcomes of manual small incision cataract surgery. Key Words: Cataract extraction, clinical audit, posterior capsular rupture, astigmatism, visual acuity.

Aim and objective The study aims to analyze fasting glucagon in patients with type 2 diabetes and impaired glucose tolerance and correlate it with anthropometric and biochemical parameters in a large proportion of Pakistani people with diabetes. Methodology The participants of the study were categorized into three groups based on oral glucose tolerance test, as per American Diabetes Association guidelines. Group A consisted of normal glucose tolerance subjects (n=30), Group B consisted of subjects with impaired glucose tolerance (n=30), and Group C had full-blown subjects with type 2 diabetes (n=30). Biochemical parameters, such as fasting glucagon, fasting plasma and 2-hour glucose, glycated hemoglobin, and lipid profile, and anthropometric parameters, such as body mass index (BMI), waist and hip circumference, waist-to-hip ratio, and systolic and diastolic blood pressure, were measured. Results The mean values of fasting glucagon level in Group A, Group B, and Group C were 39.24±4.5, 44.5±8.25, and 49.02±9.15 pg/ml, respectively. Statistically significant difference was not found in fasting glucagon level among these groups (p-value 0.614). Fasting glucagon was positively and independently correlated with 2-hour plasma glucose, systolic blood pressure, diastolic blood pressure, BMI, hip and waist circumference, and hip-to-waist ratio in Group C. In Group B, fasting glucagon was positively correlated with 2-hour plasma glucose, BMI, and hip circumference, while it was not correlated with fasting plasma glucose in both groups. In Group A, fasting glucagon found positively correlated with systolic blood pressure and hip circumference. Conclusion Our observation suggests that fasting plasma glucose is not concomitant with glucagon levels; however, glucagon suppression, after glucose intake, was dysregulated in type 2 diabetes and impaired glucose tolerance. Moreover, glucagon is associated with central obesity in type 2 diabetic patients. .

The study was designed for critical analysis of research scholar expectations in higher education at UOH. The main objective of the study was to find out research scholars expectations from university and to explore the need of enrolling themselves in higher education and the important objective is to assess the educational background of research scholar. 101 students of M. The Phil program and 15 students of Ph.D. program from the department of (education, agriculture, environmental, mathematics, forestry, management, microbiology) were chosen as the sample of the study. one questionnaire was used for collection of data. A questionnaire was used for collection of data. The questionnaire consisted of 22 items which was further divided into four sections. The first section of the questionnaire consists of the educational background of scholar, the second section consists of personal information about the scholars, the third section consists of the economic status of the scholars and the fourth most important section consist of expectations of the scholar. Open ended questions also included at the end of the questionnaire. Research was descriptive in nature and type was research was survey design the researcher personally collected data from the departments of the University of Haripur through a questionnaire.

This article reports on a compact, single layer Frequency Selective Surface (FSS) for tri-band GSM shielding applications. The proposed FSS unit cell comprises of three independent elements. The outermost square ring suppresses GSM-900 MHz signals, the innermost annular ring is incorporated in the design to stop GSM-2100 MHz signals and the middle square ring is used to suppress GSM-1800 MHz signals with a −10 dB rejection bandwidth of 600 MHz, 100 MHz, and 250 MHz, respectively. Furthermore, the proposed FSS exhibits a stable frequency response when illuminated by waves at oblique angles of incidence and a polarization insensitive behavior up-to 60°. The proposed FSS unit cell is realized on an FR4 substrate. A finite prototype containing $8 \times 7$ unit cells with an overall size of $270 \times 230\ \text{mm}^{2}$ is also fabricated and tested. A good agreement between the measured and simulated results showed that the proposed FSS can be employed for suppressing unwanted signals in the GSM-900, GSM-1800 and GSM-2100 bands.

This article reports on a compact metamaterial based electromagnetic absorber for Ku band radar applications. The proposed absorber offers −10 dB absorption from 14.29 GHz - 14.73 GHz having a maximum absorption peak at 14.6 GHz. The simulated and experimental results showed stable absorption response. Furthermore, it is experimentally shown that the proposed metamaterial absorber exhibits stable frequency response when illuminated by waves at oblique angles of incidence and polarization insensitive behavior up-to 60°. A good compliance between the measured and simulated results is observed.

This article reports on a novel Coplanar Wave-Guide (CPW) loop feed structure with an isolated circular slot in the middle to excite a higher order mode in the cylindrical Dielectric Resonator Antenna (DRA). The proposed feeding structure is etched on the bottom side of the substrate and it allows the cylindrical DRA to achieve a broader bandwidth and higher gain. For demonstration, the proposed feeding structure with the DRA is optimized at the X-band over the frequency range from 7.88 GHz to 8.78 GHz. The simulation results and experimental validation confirmed that the proposed feeding structure for the DRA can be used for achieving a broader bandwidth, higher gain, and broadside radiation characteristics.

A compact printed monopole patch antenna with finite ground for future Sub 6 GHz 5G wireless communications is presented. The microstrip patch antenna with square slot has compact size of $30\times 34\ \text{mm}^{2}$ . Good impedance match over wide range (3 – 7 GHz band) is achieved by partial ground plane and optimization of stub. The antenna exhibits omni-directional radiation pattern with high gain over the entire band. The proposed antenna is realized on FR4 laminate and good agreement with simulated results indicate that proposed design can be employed in future 5G wireless applications for wireless communication between Internet of Things nodes.

This paper reports on a novel technique of switching radiation characteristics electronically between E- and H-planes of planar Substrate Integrated Waveguide Leaky Wave Antennas (SIW-LWAs). The leaky wave mode is achieved through increasing the pitch of bounding metallic via posts on one side of SIW transmission section. The radiation switching is achieved by extending the top and bottom metallic planes to a distance of 1 mm along the leakage side. The extended section acts as a parallel plate section which is conveniently connected or disconnected from the leaking side of SIW through PIN diodes. The `ON' state of PIN diodes extends the metal guides and results in the H-plane leakage whereas `OFF' state of PIN diodes truncates the extended metal earlier and alter the leakage line boundary condition towards E-plane. The whole concept is validated by series of simulations followed by the realization and testing of the SIW-LWA. The measured radiation pattern scans about 54° in the E-plane between 10.0 GHz to 11.7 GHz, and 58° in the H-plane from 9 GHz to 10.6 GHz. The proposed topology is a suitable candidate for remote sensing and airborne applications.

The management of heart failure patients via the implantation of cardiac pacemakers has become a well-known therapy. However, the complications associated with traditional cardiac pacemakers are usually related to finite-battery life, transvenous pacing leads, and subcutaneous device pocket. In this paper, we propose a wearable RF-powered leadless pacing system, which can be implanted directly inside the heart and powered via RF energy, without any batteries or pacing leads. More specifically, we have realized a prototype rectenna-based leadless pacemaker (LP), the implant, which consists of an implantable rectenna, charging and pacing circuits, as well as the pacing electrodes. In addition, a wearable transmit-antenna array was designed, developed, and fabricated for RF energy transmission into the body. In an acute animal study, using ovine models, the proposed LP was implanted at the left ventricular apex by thoracotomy. Using the prototype wearable transmit-antenna array, the prototype LP was powered wirelessly and as a result, leadless pacing was successfully demonstrated in the in vivo ECG results. Besides measuring the efficiency of the rectenna, the computations of specific absorption rate (SAR) are presented and found to be under the IEEE recommended limits. We conclude that a wearable RF-powered leadless pacing system is realizable with the SAR under the safe levels. Thus, the proposed leadless pacing method has the potential to be significantly safer as it completely eliminates the battery, leads, and device pocket and all the associated complications.

Twitter being the most popular content sharing platform is giving rise to automated accounts called “bots”. Majority of the users on Twitter are bots. Various machine learning (ML) algorithms are designed to detect bots avoiding the vulnerability constraints of ML-based models. This paper contributes to exploit vulnerabilities of machine learning (ML) algorithms through black-box attack. An adversarial text sequence misclassifies the results of deep learning (DL) classifiers for bot detection. Literature shows that ML models are vulnerable to attacks. The aim of this paper is to compromise the accuracy of ML-based bot detection algorithms by replacing original words in tweets with their synonyms. Our results show 7.2% decrease in the accuracy for bot tweets, therefore classifying bot tweets as legitimate tweets.

In this paper, a single layer Coplanar Waveguide-fed microstrip patch antenna array is presented for biomedical applications. The proposed antenna array is realized on a transparent and flexible Polyethylene Terephthalate substrate. The design has 4 radiating elements with single CPW feed and measures only 280 × 192 mm2. The antenna array resonates at 2.68 GHz and has a peak gain of 10 dBi. A prototype is fabricated using cost effective adhesive copper foils instead of conventional copper or silver nanoparticle ink. The corresponding measured results agree well with the simulated results. The proposed low-profile and cost-efficient transmit antenna array has the potential for wearable applications, including wireless powering of implantable medical devices.

This article reports on a compact, single layer polarizer having angular independent metasurface. The proposed design can efficiently convert cross polarization to co-polarization and vice versa for X – band applications. The unit cell consists of a stretched 8 shaped element printed diagonally on an FR4 substrate having 1.6 mm thickness backed by ground plane. The proposed design converts a linearly polarized incident wave into its orthogonal counterpart after getting reflected from the metasurface polarizer provided that the incident wave is polarized in x or y axis. Two distinct polarization conversion peaks are obtained at 9.9 GHz and 11.2 GHz with overall bandwidth more than 2 GHz. The design also exhibits stable frequency response at oblique angles of incidence up-to 45°. A finite prototype with overall dimensions of 210 × 290 mm2 containing 21 × 15 unit cells is fabricated and tested. A good agreement between the measured and simulated results showed that the proposed design can be employed for linear polarization conversion applications in X band.

In this paper a wideband multilayer 45-Degree polarizer design is described in detail. The design consists of five layers of strip-lines oriented progressively from 0⁰ to 45⁰. A semi-analytical method, developed in a previous work is used to optimize the structure over the bandwidth 2 to 6 GHz. To validate the approach, patch antennas resonating at different frequencies are stacked with the polarizer. The results of the full structures are discussed over the complete bandwidth.

This paper presents a highly compact frequency-selective surface (FSS) that has the potential to switch between the X-band (8 GHz–12 GHz) and C-band (4 GHz–8 GHz) for RF shielding applications. The proposed FSS is composed of a square conducting loop with inward-extended arms loaded with curved extensions. The symmetric geometry allows the RF shield to perform equally for transverse electric (TE), transverse magnetic (TM), and 45∘ polarizations. The unit cell has a dimension of 0.176 λ0 and has excellent angular stability up to 60∘. The resonance mechanism was investigated using equivalent circuit models of the shield. The design of the unit element allowed incorporation of PIN diodes between adjacent elements for switching to a lower C-band spectrum at 6.6 GHz. The biasing network is on the bottom layer of the substrate to avoid effects on the shielding performance. A PIN diode configuration for the switching operation was also proposed. In simulations, the PIN diode model was incorporated to observe the switchable operation. Two prototypes were fabricated, and the switchable operation was demonstrated by etching copper strips on one fabricated prototype between adjacent unit cells (in lieu of PIN diodes) as a proof of the design prototypes. Comparisons among the results confirmed that the design offers high angular stability and excellent performance in both bands.

Conformal antennas placed on complex surfaces are receiving more attention as a method to increase the coverage of modern wireless communication systems. Furthermore, frequency reconfigurable antennas are being used in the development of multi-band multi-radio wireless platforms to simplify designs. In this study, theoretical development and a new 1 × 4 frequency reconfigurable self-adapting conformal antenna array that can be attached to changing conformal surfaces is presented. This conformal array consists of four reconfigurable microstrip patch antenna elements, a reconfigurable sensor circuit used to measure the curvature of the conformal surface and voltage controlled phase shifters. These phase shifters are controlled by the reconfigurable sensing circuit to implement phase-compensation to autonomously recover the pattern in both bands of the reconfigurable 1 × 4 array as the wedge- and cylindrical-shaped surface on which the array is attached upon change in shape. Throughout this study, analytical computations, simulations and measurements are compared and shown to agree.

Goal : The aim of this study is to develop a novel fully wireless and batteryless technology for cardiac pacing. Methods : This technology uses radio frequency (RF) energy to power the implanted electrode in the heart. An implantable electrode antenna was designed for 1.2 GHz; then, it was tested in vitro and, subsequently, integrated with the rectifier and pacing circuit to make a complete electrode. The prototype implanted electrode was tested in vivo in an ovine subject, implanting it on the epicardial surface of the left ventricle. The RF energy, however, was transmitted to the implanted electrode using a horn antenna positioned 25 cm above the thorax of the sheep. Results : It was demonstrated that a small implanted electrode can capture and harvest enough safe recommended RF energy to achieve pacing. Electrocardiogram signals were recorded during the experiments, which demonstrated asynchronous pacing achieved at three different rates. Conclusion : These results show that the proposed method has a great potential to be used for stimulating the heart and provides pacing, without requiring any leads or batteries. It hence has the advantage of potentially lasting indefinitely and may never require replacement during the life of the patient. Significance : The proposed method brings forward transformational possibilities in wireless cardiac pacing, and also in powering up the implantable devices.

Accurate classification of human activities is significant particularly for remote monitoring of patients requiring orthopedic treatment and therapies in case of various injuries. Previously, we presented a Local Energy-based Shape Histogram (LESH) based approach that considers the energy expenditure for various activities and differentiates among the activities on the basis of energy level. Although the approach effectively recognized various activities, the recognition accuracy for the activities, such as walking forward, walk forward left circle, and walk forward right circle was significantly low. In this paper, we present a Convolutional Neural Network (CNN) based approach for recognizing human activities with sufficiently high accuracy. The experiments are conducted on the Wearable Action Recognition Database (WARD) dataset. Experimental results demonstrate that the CNN based approach (in general) not only achieves high recognition accuracy for all of the activities but also performed extremely well for the activities requiring frequent inter-posture transitions. Another important contribution of this research is that the CNN based approach is capable of finding a single combination of sensors to identify thirteen different activities with sufficiently high accuracy.

A dual-band frequency reconfigurable monopole antenna is presented in this paper. Reconfiguration of frequency bands is achieved using RF PIN diodes. An already published antenna design is used as a starting point and is then modified to achieve frequency reconfiguration mechanism by incorporating RF PIN diodes. The antenna resonates at center frequency of 2.4 GHz and 4.25 GHz when RF PIN diodes are switched OFF. However, RF PIN diodes ON state resulted in 1.84 and 3.66 GHz frequency bands. The 1.84 and 2.45 GHz bands are controlled by altering the electrical length of inverted L-shaped resonator. Whereas, C-shaped radiator is used to resonate the proposed antenna at 3.66 GHz and 4.56 GHz frequency bands. Overall, the simulation and measurement results showed a good agreement.

A cylindrically shaped surface consisting of microstrip structures is presented in this article as a new technique to reduce the mutual coupling between the elements in a 1 × 2 microstrip patch array. Initially, the surface was simulated in HFSS for functionality, manufactured, and then, the prototype was measured in an anechoic chamber at 3.89 GHz. The surface comprised of a number of 2-port microstrip (2-PM) elements interconnected into a cylindrical shape with a radius of 1.02λ to enclose a particular region. Each 2-PM element had the capability of coupling an incident EM field on the surface and transmitting the field to the adjacent interconnected elements. Then, because the 2-PM elements were connected in to a cylindrical shape, the incident EM field was re-radiated from the other interconnected 2-PM elements in a direction away from the transmitter; achieving a behavior similar to an electromagnetic cloak. Finally, the surface was used to reduce the coupling between two microstrip elements in an array. Overall, simulation and measurement results were in good agreement with each other and were shown to reduce the mutual coupling between the elements by 8.0 dB, and have little effect on the radiation properties of the overall 2-element array. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:296–301, 2016

A new compact multiple-input multiple-output (MIMO) ultra-wideband (UWB) antenna array is presented. The antenna array initially consisted of two monopoles placed side by side at a distance of 4 mm. A strong mutual coupling was observed so the design was modified by rotating the second radiator at 90° at a distance of 1 mm. Wideband isolation is achieved by exploiting polarisation diversity of antenna elements. Simulation in HFSS and printed prototype results validate the high isolation, over 21 dB on the entire 2.5–12 GHz frequency range. A prototype was fabricated on a low loss substrate of Rogers TMM4 measuring 23 × 39.8 mm2. To evaluate the diversity performance, the envelope correlation coefficient was calculated resulting below −20 dB, thus ensuring good diversity performance. The compactness of the proposed UWB-MIMO design is finally compared against alternative solutions already present in the literature.

This letter reports on a compact planar dual-band Multiple-Input and Multiple-Output (MIMO) antenna for Wireless Local Area Network (WLAN) applications. The proposed antenna primarily consists of two meandered monopole radiators that are decoupled by introducing a folded Y-shape isolator element and it is shown that the edge coupling between the radiators and isolator introduces the resonance at the lower band. The miniaturization is achieved by passing the signal on to the bottom layer where a meandered line conductor introduces a broadside coupling with the radiator, originating the higher band resonance. The antenna operates between 2.4 GHz to 2.5 GHz and 5.45 GHz to 5.65 GHz with an isolation of more than 25 dB and 15 dB, respectively. The antenna measures only $19 \times 23~\hbox{mm}^2$ .

A Multiple-input multiple-output antenna array with two radiating elements having a wide bandwidth is reported in this work. Spatial diversity has been introduced to achieve the diversity gain and the array was kept compact by introducing five parasitic decoupling ele- ments on the bottom of the substrate; each having a length equal to k/2 at a specific frequency. Each resonant element offers a resonant band- width of 1 GHz starting from 3 GHz to 8.5 GHz. Good agreement between the measured and simulated results shows that the antenna sys- tem performs very well over the frequency range 3 GHz to 8.5 GHz. In addition, an isolation of more than 15 dB is achieved with the help of the parasitic elements, while keeping an edge-to-edge and center-to- center separation of 4 mm and 19 mm, respectively. The proposed antenna measures 26 3 40.5 mm 2 , and it is suitable for handheld devi- ces, personal digital assistants, next generation home entertainment sys- tems, and robots. V C 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1677-1682, 2015; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.29162

A compact tri band slot loaded defected ground microstrip patch antenna, operating on three frequencies is presented. The antenna operates effectively at 3, 5.3 and 8 GHz. Simulated return loss at 3 GHz, 5.3 GHz and 8 GHz turns out to be −11.59 dB, −17.52 dB and −16.42 dB, respectively. The proposed antenna is compact in size and has been designed using FR4 epoxy substrate with a relative permittivity of 4.4. The design uses differently spaced rectangular and T-shaped slots in the patch and a defected ground structure with square and U-shaped slots. The proposed antenna can find applications in different wireless systems like WLAN and WiMAX. The implemented design is simulated using High Frequency Structure Simulator (HFSS). The proposed design has also been fabricated and the return loss has been measured and found in agreement with the simulated values.

As the concerns regarding Zika virus (ZIKV) are mostly of neurological disorders, especially in neonates and infants, other possible threats of the virus may have been overlooked. Our study focuses on the potential threat that ZIKV may pose to the heart like that of similar arboviral diseases. We conducted a literature search of multiple terms in March 2017 using the search engines, PubMed, Embase, and SCOPUS. Articles were then reviewed by two independent reviewers, adhering strictly to our review criteria. No discriminations were made whether the studies were conducted on human or non-human subjects. Three relevant studies were shortlisted and finalized. The nature of the studies is as follows: prospective observational multicenter study (n = 9), case report (n = 1), and animal studies (n = 5). The studies suggested an association between cardiovascular complications and ZIKV in the acute phase of the infection. We recognize the limitations of our study owing to the paucity of the sample size of our literature review. However, the significant findings have also proved the dire need to conduct more research to further back the possibility of ZIKV's influence on the cardiac cells. Closely studying these associations can eventually help develop a vaccine for ZIKV in the near future.

Heart failure (HF) is a pressing health concern as the expense of hospitalization financially burdens the health care system. Hemodynamic monitoring has the potential to detect increases in intracardiac filling pressures weeks before clinical deterioration; hence, preliminary findings of volume overload with the use of these devices may prevent the progression of disease and lead to a reduction in HF-associated hospitalizations. We extensively searched PubMed, Ovid SP, Embase, and Cochrane databases to identify all the possible studies that assess the effect of hemodynamic monitoring on hospitalizations in HF patients. The main outcomes considered were the rate of HF hospitalization, mortality, quality of life, and improvement in New York Heart Association (NYHA) functional class in the monitored group. Seven studies met all the eligibility criteria and were incorporated in our systematic review. Out of the seven studies we reviewed, three studies inserted the sensor in the pulmonary artery, three in the right ventricle, and only one in the left atrium. On an average, the single study on the left atrium showed the highest reduction (59.0%) in HF hospitalization followed by the pulmonary artery (56.3%) and right ventricle (31.0%), respectively. Our systematic review demonstrates that the use of hemodynamic sensors in HF patients helps to reduce HF-related hospitalizations. Therefore, a combination of outpatient monitoring via the use of hemodynamic sensors and fluid management is needed to reduce HF hospitalizations and improve outcomes in HF patients.

The effects of low dose rivaroxaban (2.5 mg BID) on patients with coronary artery disease (CAD) receiving background antiplatelet therapy remains uncertain. Five randomized controlled trials reporting CV outcomes in ≥500 patients at ≥ 1 year were selected using MEDELINE, EMBASE and CENTRAL

Acute oesophageal necrosis, also known as ‘black oesophagus’, is a rare condition characterised by the black discolouration of the oesophageal mucosa on endoscopy and involves the distal oesophagus in majority of cases but may also extend proximally. A number of conditions are found to be associated with it and it is thought to occur due to a combination of hypovolaemia and inadequate oesophageal protective mucosal barrier function. Gastric secretions may have a direct effect on the oesophageal mucosa. We present a case of a woman who presented with haematemesis and significant hypotension after a session of haemodialysis. Black oesophagus was confirmed on esophagogastroduodenoscopy. She was given two units of packed red blood cells and one unit of platelets, and started on a pantoprazole infusion. However, despite rigorous attempts at resuscitation the patient failed to recover.

A compact planar UWB-MIMO antenna array with WLAN band rejection is presented. The array consists of four monopole radiators and a common ground plane. These monopoles are placed in such a way that the polarisation diversity of nearly placed radiators is exploited, resulting in high isolation. The proposed MIMO antenna array is electrically small (50 × 39.8 mm2), printed on a low loss 1.524 mm thick Rogers TMM4 laminate with a dielectric constant of 4.5 and a loss tangent of 0.002. A band-stop design was inserted on the ground plane to behave similar to a LC band-stop filter and reject the WLAN band. Simulation and measurement results satisfy the return loss requirement of better than 10 dB and isolation better than 17 dB over the entire 2.7–5.1 and 5.9–12 GHz bandwidths.

The system design of an integrated microwave imaging radar for the diagnostic screening of breasts cancer is presented. A custom integrated circuit implemented in a 65-nm CMOS technology and a pair of patch antennas realized on a planar laminate are proposed as the basic module of the imaging antenna array. The radar operates on the broad frequency range from 2 to 16 GHz with a dynamic range of 107 dB. Imaging experiments carried out on a realistic breast phantom show that the system is capable of detecting tumor targets with a resolution of 3 mm.

The purpose of this letter is to introduce a compact ultrawideband (UWB) diversity antenna with a very low envelope correlation coefficient (ECC). The design employs a hybrid isolation enhancing and miniaturization technique. The antenna consists of two counter facing monopoles, and is miniaturized by using not only inverted-L stubs but also a complementary split-ring resonator (CSRR) on the ground plane. The added components enhance isolation and enable tighter packing of the antennas. The result is a very compact multiple-input–multiple-output (MIMO) array with an overall size of 23 $\times$ 29 mm2 , which covers the entire UWB spectrum from 3 to 12 GHz, with mutual coupling lower than –15 dB. Moreover, the CSRR unit that acts as a resonator is applied for the first time to suppress the interference of RF currents flowing through the ground plane of this UWB-MIMO/diversity antenna. The performance of the fabricated prototype in terms of scattering parameters, broadside (peak) gain, radiation patterns, efficiency, and ECC is presented and discussed.

In this paper, the wave propagation of a graphene based conductor (GBC) transmission line (TL) and its comparison with a copper TL on a conformal surface is presented. An investigation of the coupling between parallel GBC TLs and copper TLs is also summarized in this work. A 150 mm long TL was initially manufactured on a flexible substrate and the wave propagation characteristics were investigated on a conformal surface. Then, a microstrip copper TL was manufactured and the wave propagation on a conformal surface was compared with the GBC TL. Also, prototypes with various combinations of two parallel TLs (GBC — GBC TLs, GBC TL — Copper TLs, etc.) were manufactured and studied for comparison. It was shown that the wave propagation properties of a given GBC TL on a conformal surface were similar to that of a copper TL over the frequency band of 100 KHz to 8.5 GHz. Moreover, results of the near- and far-end coupling showed that the GBC TLs can be used as an alternative to copper TLs as they can provide better coupling on a conformal surface.

In this paper, the use of a carbon microfiber bundle (CMB) is investigated for manufacturing a monopole antenna. In particular, the radiating properties of a carbon microfiber bundle, having filaments of 7 μm in diameter, were studied as a monopole. The proposed monopole was mounted vertically on two separate types of ground plane, i.e., a small copper and a large aluminum ground plane. The monopole design was modeled in HFSS. To analyze the radiation characteristics of the microfibers and its shift in the resonant frequency, CMB monopole antenna prototypes with various lengths were manufactured and tested in an anechoic chamber. Overall, the simulation results agreed well with the measured results. Prototypes manufactured on the larger ground plane showed higher gain as compared to those on the smaller ground plane, with no significant difference in the matching characteristics. Overall, it was demonstrated that the light weight, low cost carbon microfiber bundle can be used to design an antenna for a range of resonant frequencies.

In this paper, a novel ultra-wide band (UWB) antenna comprised of graphene-based conductor (GBC) sheets is proposed. The proposed antenna is designed and simulated in a full-wave 3D EM solver and fabricated using a GBC sheet on a TMM4 substrate. Simulations and measurement results agree well, showing an overall matching from 2.65 to 10 GHz. Bandwidth and gain of the proposed antenna were also compared with a conventional UWB antenna made of copper. Impedance matching and the bandwidth of the conventional antenna were found better than the proposed GBC antenna, owing to variations in the material properties. Overall though, the results showed that the GBC sheet has good UWB characteristics and therefore can be used for UWB applications.

Natural resources, infrastructure and human resources play an important role in the development of a country. It is a worldwide proven fact that the development of a nation depends on availability of natural resources (24%), infrastructure (16%) and human resources that add 60%. In the present sociopolitical and economic scenario of the world, the block of Muslim countries is recognized as developing or under developed despite being rich in the natural resources on the Earth as well as being blessed with abundant human resources. This paper gives a full reflection of natural resources, infrastructure and human resources of the Muslim world as compared to the rest of the world. It highlights the root causes for the prevalent miserable state of theMuslim Ummah. It also presents a model for the training, retraining and development of human resources of the Muslim world as a remedial measure to stand as part of the developed world

An ultra-compact planar antenna aiming to be part of an imaging antenna array operating in the broad 3–18 GHz frequency range is presented. The antenna is made of two closely packed wide-band monopoles for simultaneous transmission and reception functionalities. A high isolation ( >20 dB) between the two patches is achieved through the insertion of a structured ground plane (decoupling structure). A prototype was fabricated on a Roger R4003c laminate measuring 58 × 33 mm2 and used in inverse synthetic array radar configuration for detecting a steel object with sub-centimetre spatial resolution.

A multiple-input-multiple-output (MIMO) antenna with dual polarization, operating in the UWB frequency range is proposed. The radiator is shared by the two antenna elements, which greatly reduces the overall size of the MIMO antenna system. Slots are etched in the radiator to achieve the desired isolation among the elements. Dual polarization characteristics of the radiator are attained in the far-field due to orthogonal currents. The comparison of simulated and measured results show that the proposed MIMO antenna operates on a wide range from 3 to 11 GHz with a low mutual coupling (

This letter presents the design of a frequency-reconfigurable series-fed microstrip patch array in which the elements are interconnected with composite right/left-handed transmission lines (CRLH-TLs). Reconfigurable CRLH-TLs are used instead of meandered microstrip lines to reduce the overall size of the array and provide two different zero-phase frequencies of operation for broadside radiation in both instances. p-i-n diodes were used to reconfigure the array by changing the electrical lengths of the patches and microstrip sections of the CRLH-TLs. The measurements were taken in an anechoic chamber to verify the simulation results. The array can be reconfigured to operate at 1.97 and 2.37 GHz.

In modern computing paradigms, energy consumption is of foremost importance because it constitutes a major percentage of the operational expenses. Virtual Machines (VMs) are consolidated on a fewer number of servers to significantly reduce the overall power consumption. The idle servers are then turned off by using Dynamic threshold Voltage Scaling (DTVS). The VM monitor checks for under-utilized, partially filled, over-utilized, and empty servers. The VM monitor then transfers the tasks to suitable servers for execution if subject to a set of constraints. As a result, many servers those were under-utilized get idle and are turned off by using DTVS to save power. Simulation results affirm our study and a substantial reduction is observed in the overall power consumption of the cloud data centers.

Drilling techniques in exploration of oil and gas, adopted around the world, involves optimization of controllable variable during drilling operations. The drilling optimization procedures, involves better understanding of operational as well as equipment parameter on ROP (Rate of Penetration). The objective of optimization is to estimate a reasonable rate of penetration to reduce drilling time, cost and consequently early discovery of oil and gas. In this case study, optimum penetration rate of Kohat/Potohar region, where drilling is extremely problematic due to subsurface conditions specifically for muree and Kuldana formations, are obtained by two methods-mathematical & comparative. Comparative method uses cost per foot, specefic energy and rae of penetration with respect to depth comparison charts and give optimum drilling parameters while for mathematical model, BYM penetration model has been preferred to adress several drilling factors by using past drilling data of wells of Kohat region. Important parameters like ECD, Pore pressure gradient, evaluation of tooth wear and jet impact forces calculation are made for examining inter-relationship of controllable factors. At last a statistical approach of multiple regression analysis are made by using Matlab.Results of Matlab are further employed in determination of optimized parameters. Outcome from analysis are used to compare results with comparative approach and obtain optimum values of drilling rate, RPM and WOB for respective formations. Based on these approaches, potential risks can be mitigated which help to boost drilling performance and provides effective parameters for drilling of future wells in Kohat region.

In this paper, an initial study on the possible use of carbon microfibers as a transmission line (TL) feed network in conformal microstrip antenna arrays was conducted. Initially, a 12.0 cm long 50 Ω microfiber transmission line was manufactured and the wave propagation properties were measured. These characteristics were then compared to the propagation properties of a traditional copper microstrip TL with the same length. Once these propagation characteristics were determined, two parallel TLs with a separation of 4.0 mm were then manufactured to investigate the unwanted coupling that may occur in a feed network of an array. One of these TLs was a copper microstrip line and one was a microfiber TL with similar dimensions. Overall, it has been shown that the microfiber TLs support wave propagation in a manner similar to the copper microstrip TLs but the attenuation constant was larger, as the 3 dB point was at 2.5 GHz. Also it was evident from the measurements that the microfiber TLs were more immune to coupling at high frequencies. The results demonstrated that these properties made microfiber TLs a good possible candidate for the feed network of a conformal microstrip antenna array.

A compact multiband design of a printed microstrip patch antenna with two rectangular U-shaped parasitic elements is introduced in this paper. The rectangular U-shaped parasitic elements were used for the 2nd and 3nd mode excitation, multi-band resonance and control of the resonance frequencies. The simulation and measurement results showed that the antenna resonates at the frequencies of 2:6 GHz, 6.0 GHz, and 8.5 GHz. The antenna has an overall area of 40.0 × 30.0 mm2.

Conformal antennas printed on thin flexible sub-strates typically use copper conductors for the radiating portion of the designs. This paper presents an alternative to using copper conductors. More particularly, a novel compact monopole on a thin transparent substrate with 25 µm thick flexible graphene-based conductors for the radiating portion of the design is presented. The design was modeled in a full-wave simulation tool, and a prototype was manufactured and measured in a full anechoic chamber. Overall, it was shown that the S-parameter simulations agreed well with measurements and that the electrical benefits of the flexible graphene-based conductors could be used to design a useful conformal monopole.