2020 IEEE Wireless Communications and Networking Conference (WCNC)
Flying drones can be used in a wide range of applications and services from surveillance to packa... more Flying drones can be used in a wide range of applications and services from surveillance to package delivery. To ensure robust control and safety of drone operations, cellular networks need to provide reliable wireless connectivity to drone user equipments (UEs). To date, existing mobile networks have been primarily designed and optimized for serving ground UEs, thus making the mobility support in the sky challenging. In this paper, a novel handover (HO) mechanism is developed for a cellular-connected drone system to ensure robust wireless connectivity and mobility support for drone-UEs. By leveraging tools from reinforcement learning, HO decisions are dynamically optimized using a Q-learning algorithm to provide an efficient mobility support in the sky. The results show that the proposed approach can significantly reduce (e.g., by 80%) the number of HOs, while maintaining connectivity, compared to the baseline HO scheme in which the drone always connects to the strongest cell.
A 2 × 2 high-intensity CMUT transmit array that is capable of two-dimensional beam steering is pr... more A 2 × 2 high-intensity CMUT transmit array that is capable of two-dimensional beam steering is presented. The device uses an ac drive voltage at half the ultrasound frequency without any dc bias, enabling the usage of the entire gap height. The device is designed using a large signal equivalent model approach. A fabrication method that requires a single lithographic mask has been used. The fabricated devices are operated at 76 kHz to beam steer at various angles. An equivalent element pressure of 144 dB//20 µPa at the transducer surface was measured. The entire half-space can be steered without any sidelobes and the beam obtained from the array is in excellent agreement with the theoretical predictions.
Testosterone and its metabolites—estrogen and dihydrotestosterone— are involved in the brain sex ... more Testosterone and its metabolites—estrogen and dihydrotestosterone— are involved in the brain sex differentiation during the perinatal period by binding to androgen receptors (AR) or estrogen recept...
This paper provides a comprehensive and details of the current technological state of the Blockch... more This paper provides a comprehensive and details of the current technological state of the Blockchain technology. The review outlines in details what is required for the Blockchain technology to function in development of cryptocurrency and the required factors for success. Conclusively, it is noted that the Blockchain technology in its current state still has way to go before the technology will reach a state considered sufficient for mainstream adoption.
Low intrinsic stability has marred the production of psychrophilic proteins in commonly used meso... more Low intrinsic stability has marred the production of psychrophilic proteins in commonly used mesophilic systems. This may lead to a lopsided bias towards the expression of the few psychrophilic proteins which can manage a stable structure at those temperatures. Of the two possible approaches to help counterpoise the expression in favour of most psychrophilic proteins, the approach we have taken is to develop a new psychrophilic host. Rather than characterizing novel strains, we plan on converting a highly characterized system in synthetic biology, E.coli, by introducing genes that confer cold-tolerance to it thereby reducing dependency on regular mesophilic hosts and possibly making it the model system for cold temperature-based systems.
We present a project-based learning prototype for visual analysis of petrophysical properties usi... more We present a project-based learning prototype for visual analysis of petrophysical properties using 2D cross-sections and micro-models of porous media. Micro-computed Tomography (CT) scans are used to create the quasi-2D micro-models that are printed using Stereolithography (SLA) 3D printers to study petrophysical properties in porous media. The methodology involves obtaining 8 different cross-sections of rocks either from micro-CT scans or online libraries. 2D cross-sections are segmented into black and white binary images and then skeletonized to create quasi-2D models. The flow of oil and water in initially water saturated pores in the printed 2D models mimics the drainage and imbibition processes, respectively. High definition photography is used to capture still and dynamic photographs of flow processes. The binary images are used to analyze porosity and grain size distribution while the still and dynamic photographs are used to analyze fluid saturation and displacement efficie...
BackgroundAsylum seekers and refugees (ASRs) often experience poor health in host countries. The ... more BackgroundAsylum seekers and refugees (ASRs) often experience poor health in host countries. The United Nations High Commissioner for Refugees (UNHCR) requires hosts to ensure these sanctuary seekers have access to basic health care.AimTo identify barriers and facilitators that affect access to health care by ASRs in Wales.Design & settingParticipatory research approach using qualitative focus groups across Wales, which hosts 10 000 refugees.MethodEight focus groups were undertaken with ASRs, support workers, and volunteers (n = 57).ResultsSpecialist NHS-funded services and grant-aided non-governmental organisations (NGOs) facilitated access to health care, including primary care. Most ASRs understood the role of general practice in providing and coordinating care, but were unaware of out-of-hours services. Reported barriers included: language difficulties, health literacy, unrecognised needs, and the cost of travel to appointments. Participants recognised the importance of mental h...
In Release 13 the Third Generation Partnership Project (3GPP) developed the Narrowband Internet o... more In Release 13 the Third Generation Partnership Project (3GPP) developed the Narrowband Internet of Things (NB-IoT). It is a cellular technology providing wireless connectivity to machine-type services and applications. In 3GPP Releases 14 and 15, NB-IoT evolved to meet the requirements defined for a fifth generation (5G) communications system in 3GPP and in the International Telecommunications Union Radiocommunication (ITU-R) sector. This paper introduces NB IoT in the context of 3GPP's recent work on 5G. It presents the ITU-R International Mobile Telecommunication 2020 (IMT 2020) and 3GPP 5G performance requirements. A complete evaluation of the NB IoT performance for each of these requirements is presented, and it is shown that NB IoT meets the 5G performance requirements for massive IoT (mIoT) services.
Background and Objective: The Coronavirus disease 2019 first appeared in the area of Wuhan, China... more Background and Objective: The Coronavirus disease 2019 first appeared in the area of Wuhan, China. Dental professionals are at greater risk of getting infected by patients and certain dental procedures involving aerosol generation and proximity to the oropharyngeal region. Therefore, Personal Protective Equipment (PPE) is recommended to protect skin and mucosa from infected blood or saliva. American Dental Association (ADA) has published recommendations for dental treatment, yet most of the dentists are still hesitant in treating patients. The objective of this study was to assess the knowledge and practices of dentists in Pakistan regarding PPE during COVID-19 pandemic. Methods: Data collection was done using a well-structured web-based questionnaire (Google forms). The survey form was disseminated by sending the link via email, WhatsApp and other online forums. Results: A total of n = 1016 responses were collected. Approximately 91.6% of the participants were young dentists with y...
Droplet impact on a miscible liquid film finds several applications in scientific and engineering... more Droplet impact on a miscible liquid film finds several applications in scientific and engineering problems. Here, we report that how pre-existing perturbations of a target liquid film, in the form of surface waves, change the impact dynamics and splashing phenomena. For this purpose, we release dyed water droplets and study droplet impact dynamics on a wavy water film, where the waves atop the liquid film are generated by imposing low-frequency two-dimensional (2D) lateral (horizontal) vibrations on glass substrates. Methylene blue-dyed droplet was employed to facilitate the observation of the details of mixing phenomenon given its importance in some applications such as casting homogeneous thin-film coatings. The results are compared with the impact on a quiescent/smooth liquid surface. Splashing is found to be more pronounced for the wavy surface given the additional energy imparted by vibrations and waves. An increase in the crown diameter is also observed for the vibrated wavy liquid film. It is observed that mixing is enhanced significantly in the presence of vibrations and surface waves. The interaction between the pre-existing surface waves and the waves formed after the droplet impact is also studied.
Abstract Pattern-forming instability in various fields is an interesting research topic because o... more Abstract Pattern-forming instability in various fields is an interesting research topic because of its complex physical nature and numerous applications. In this paper, we experimentally study capillary surface waves and patterns formed on a liquid film, cast on a plane substrate without physical walls, but pinned to the substrate edges, and subjected to multi-axis horizontal (lateral) oscillations (55–333 Hz). The effect of single-axis ultrasonic horizontal vibrations (20–170 kHz) was also investigated. We show that using substrates with different geometrical shapes and various travelling paths created by multi-axis vibrations with a phase angle difference between the axes produce a plethora of standing and travelling wave patterns on the liquid film surface. We report perfect standing square and spiral-like patterns for low-frequency multi-axis horizontal vibrations, which are commonly observed for vertical vibrations, while the mechanisms of momentum transfer to the liquid film from the vibrating substrate are different in vertical and horizontal vibrations. Other patterns forming on the liquid film surface in our experiments include lines/stripes, circles, swirls, pentagons, triangles, etc. It is also reported that low-frequency excitations create harmonic travelling waves and standing patterns, while the frequency of response waves generated by the application of ultrasonic horizontal vibrations is several orders of magnitude less than the excitation frequency. No subharmonic cross-waves are observed in this study, which strengthens the idea that plane substrates (without walls) are a good approximation for the theoretical case of a horizontally vibrated liquid film with infinite lateral length.
Changes in temperature regimes, precipitation regimes, and extreme weather events as a result of ... more Changes in temperature regimes, precipitation regimes, and extreme weather events as a result of climate change can cause physiological stress to urban tree species. This study examines the City of Mississauga's urban forest species composition to explore the vulnerability of commonly planted native and non-native species under projected climate change scenarios. A vulnerability matrix was created to highlight the potential vulnerability of species to particular climate Thank you to
Electrical impedance tomography (EIT) has been a hot topic among researchers for the last 30 year... more Electrical impedance tomography (EIT) has been a hot topic among researchers for the last 30 years. It is a new imaging method and has evolved over the last few decades. By injecting a small amount of current, the electrical properties of tissues are determined and measurements of the resulting voltages are taken. By using a reconstructing algorithm these voltages then transformed into a tomographic image. EIT contains no identified threats and as compared to magnetic resonance imaging (MRI) and computed tomography (CT) scans (imaging techniques), it is cheaper in cost as well. In this paper, a comprehensive review of efforts and advancements undertaken and achieved in recent work to improve this technology and the role of artificial intelligence to solve this non-linear, ill-posed problem are presented. In addition, a review of EIT clinical based applications has also been presented.
Journal of artificial organs : the official journal of the Japanese Society for Artificial Organs, 2018
The aim of this work was to analyze a shrouded impeller pediatric ventricular assist device (SIP-... more The aim of this work was to analyze a shrouded impeller pediatric ventricular assist device (SIP-VAD). This device has distinctive design characteristics and parameter optimizations for minimization of recirculation flow and reduction in high-stress regions that cause blood damage. Computational Fluid Dynamics (CFD) simulations were performed to analyze the optimized design. The bench-top prototype of SIP-VAD was manufactured with biocompatible stainless steel. A study on the hydrodynamic and hemodynamic performance of the SIP-VAD was conducted with predictions from CFD and actual experimentation values, and these results were compared. The CFD analysis yielded a pressure range of 29-90 mmHg corresponding to flow rates of 0.5-3 L/min over 9000-11000 rpm. The predicted value of the normalized index of hemolysis (NIH) was 0.0048 g/100 L. The experimental results with the bench-top prototype showed a pressure rise of 30-105 mmHg for the flow speed of 8000-12000 rpm and flow rate of 0.5...
The Primary Care Companion For CNS Disorders, 2016
Despite the numerous advantages of linezolid therapy, one disadvantage continuing to hinder its u... more Despite the numerous advantages of linezolid therapy, one disadvantage continuing to hinder its use is the risk of serotonin syndrome when coadministered with other serotonergic agents. Developing a better understanding of serotonin syndrome is essential for the prevention and management of this potentially life-threatening condition. This report describes a patient with schizophrenia, depression, and severe, acute osteomyelitis. The patient was taking multiple serotonergic agents and required the use of linezolid without the possibility of a sufficient washout period. The severity of the patient's condition in conjunction with increased risk for serotonin syndrome warranted prophylactic treatment with cyproheptadine. The complex pathophysiology of prophylactic treatment of serotonin syndrome with cyproheptadine is worthy of discussion.
We report on the reduction of contact resistance in solution-processed TIPS-pentacene (6,13-bis(t... more We report on the reduction of contact resistance in solution-processed TIPS-pentacene (6,13-bis(triisopropylsilylethynyl)pentacene) and PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]) top-gate bottom-contact organic field-effect transistors (OFETs) by using different contact-modification strategies. The study compares the contact resistance values in devices that comprise Au source/drain electrodes either treated with 2,3,4,5,6-pentafluorothiophenol (PFBT), or modified with an evaporated thin layer of the metal-organic molecular dopant molybdenum tris-[1,2-bis(trifluoromethyl)ethane-1,2-dithiolene] (Mo(tfd)3), or modified with a thin layer of the oxide MoO3. An improved performance is observed in devices modified with Mo(tfd)3 or MoO3 as compared to devices in which Au electrodes are modified with PFBT. We discuss the origin of the decrease in contact resistance in terms of increase of the work function of the modified Au electrodes, Fermi-level pinning effects, and decrease ...
When dynamic load modulation (DLM) based transmitter architecture is used with broadband signals ... more When dynamic load modulation (DLM) based transmitter architecture is used with broadband signals such as Wideband code division multiple access (WCDMA) or Long term evolution (LTE), the envelope signal required to control the load impedance and thus the RF output of PA has very wide bandwidth. It is very difficult to design a transmitter system for such a wideband control signal. In this thesis work, different schemes are investigated for the bandwidth reduction of wideband control signals in Dynamic load modulation (DLM) transmitter architectures. The schemes are implemented using different techniques, based on digital signal processing (DSP) and the simulated results are shown in Matlab. These techniques are capable to reduce the bandwidth of the envelope signal while maintaining high average efficiency of power amplifiers. A single carrier WCDMA signal having bandwidth 3.84 MHz is used as the desired output signal in demonstrating the techniques although the techniques can be well applied to multicarrier signals. The bandwidth of the optimal baseband envelope signal is 12.5 MHz with overall average efficiency of 54%. It is effectively reduced to 4 MHz while retaining high efficiency which is around 49%. The target reduced bandwidth is chosen as 4 MHz to show the effectiveness of the techniques, further in the condition of keeping relatively high average efficiency of PA. Moreover, the efficiency is also compared at different reduced bandwidths for the implemented methods.
2020 IEEE Wireless Communications and Networking Conference (WCNC)
Flying drones can be used in a wide range of applications and services from surveillance to packa... more Flying drones can be used in a wide range of applications and services from surveillance to package delivery. To ensure robust control and safety of drone operations, cellular networks need to provide reliable wireless connectivity to drone user equipments (UEs). To date, existing mobile networks have been primarily designed and optimized for serving ground UEs, thus making the mobility support in the sky challenging. In this paper, a novel handover (HO) mechanism is developed for a cellular-connected drone system to ensure robust wireless connectivity and mobility support for drone-UEs. By leveraging tools from reinforcement learning, HO decisions are dynamically optimized using a Q-learning algorithm to provide an efficient mobility support in the sky. The results show that the proposed approach can significantly reduce (e.g., by 80%) the number of HOs, while maintaining connectivity, compared to the baseline HO scheme in which the drone always connects to the strongest cell.
A 2 × 2 high-intensity CMUT transmit array that is capable of two-dimensional beam steering is pr... more A 2 × 2 high-intensity CMUT transmit array that is capable of two-dimensional beam steering is presented. The device uses an ac drive voltage at half the ultrasound frequency without any dc bias, enabling the usage of the entire gap height. The device is designed using a large signal equivalent model approach. A fabrication method that requires a single lithographic mask has been used. The fabricated devices are operated at 76 kHz to beam steer at various angles. An equivalent element pressure of 144 dB//20 µPa at the transducer surface was measured. The entire half-space can be steered without any sidelobes and the beam obtained from the array is in excellent agreement with the theoretical predictions.
Testosterone and its metabolites—estrogen and dihydrotestosterone— are involved in the brain sex ... more Testosterone and its metabolites—estrogen and dihydrotestosterone— are involved in the brain sex differentiation during the perinatal period by binding to androgen receptors (AR) or estrogen recept...
This paper provides a comprehensive and details of the current technological state of the Blockch... more This paper provides a comprehensive and details of the current technological state of the Blockchain technology. The review outlines in details what is required for the Blockchain technology to function in development of cryptocurrency and the required factors for success. Conclusively, it is noted that the Blockchain technology in its current state still has way to go before the technology will reach a state considered sufficient for mainstream adoption.
Low intrinsic stability has marred the production of psychrophilic proteins in commonly used meso... more Low intrinsic stability has marred the production of psychrophilic proteins in commonly used mesophilic systems. This may lead to a lopsided bias towards the expression of the few psychrophilic proteins which can manage a stable structure at those temperatures. Of the two possible approaches to help counterpoise the expression in favour of most psychrophilic proteins, the approach we have taken is to develop a new psychrophilic host. Rather than characterizing novel strains, we plan on converting a highly characterized system in synthetic biology, E.coli, by introducing genes that confer cold-tolerance to it thereby reducing dependency on regular mesophilic hosts and possibly making it the model system for cold temperature-based systems.
We present a project-based learning prototype for visual analysis of petrophysical properties usi... more We present a project-based learning prototype for visual analysis of petrophysical properties using 2D cross-sections and micro-models of porous media. Micro-computed Tomography (CT) scans are used to create the quasi-2D micro-models that are printed using Stereolithography (SLA) 3D printers to study petrophysical properties in porous media. The methodology involves obtaining 8 different cross-sections of rocks either from micro-CT scans or online libraries. 2D cross-sections are segmented into black and white binary images and then skeletonized to create quasi-2D models. The flow of oil and water in initially water saturated pores in the printed 2D models mimics the drainage and imbibition processes, respectively. High definition photography is used to capture still and dynamic photographs of flow processes. The binary images are used to analyze porosity and grain size distribution while the still and dynamic photographs are used to analyze fluid saturation and displacement efficie...
BackgroundAsylum seekers and refugees (ASRs) often experience poor health in host countries. The ... more BackgroundAsylum seekers and refugees (ASRs) often experience poor health in host countries. The United Nations High Commissioner for Refugees (UNHCR) requires hosts to ensure these sanctuary seekers have access to basic health care.AimTo identify barriers and facilitators that affect access to health care by ASRs in Wales.Design & settingParticipatory research approach using qualitative focus groups across Wales, which hosts 10 000 refugees.MethodEight focus groups were undertaken with ASRs, support workers, and volunteers (n = 57).ResultsSpecialist NHS-funded services and grant-aided non-governmental organisations (NGOs) facilitated access to health care, including primary care. Most ASRs understood the role of general practice in providing and coordinating care, but were unaware of out-of-hours services. Reported barriers included: language difficulties, health literacy, unrecognised needs, and the cost of travel to appointments. Participants recognised the importance of mental h...
In Release 13 the Third Generation Partnership Project (3GPP) developed the Narrowband Internet o... more In Release 13 the Third Generation Partnership Project (3GPP) developed the Narrowband Internet of Things (NB-IoT). It is a cellular technology providing wireless connectivity to machine-type services and applications. In 3GPP Releases 14 and 15, NB-IoT evolved to meet the requirements defined for a fifth generation (5G) communications system in 3GPP and in the International Telecommunications Union Radiocommunication (ITU-R) sector. This paper introduces NB IoT in the context of 3GPP's recent work on 5G. It presents the ITU-R International Mobile Telecommunication 2020 (IMT 2020) and 3GPP 5G performance requirements. A complete evaluation of the NB IoT performance for each of these requirements is presented, and it is shown that NB IoT meets the 5G performance requirements for massive IoT (mIoT) services.
Background and Objective: The Coronavirus disease 2019 first appeared in the area of Wuhan, China... more Background and Objective: The Coronavirus disease 2019 first appeared in the area of Wuhan, China. Dental professionals are at greater risk of getting infected by patients and certain dental procedures involving aerosol generation and proximity to the oropharyngeal region. Therefore, Personal Protective Equipment (PPE) is recommended to protect skin and mucosa from infected blood or saliva. American Dental Association (ADA) has published recommendations for dental treatment, yet most of the dentists are still hesitant in treating patients. The objective of this study was to assess the knowledge and practices of dentists in Pakistan regarding PPE during COVID-19 pandemic. Methods: Data collection was done using a well-structured web-based questionnaire (Google forms). The survey form was disseminated by sending the link via email, WhatsApp and other online forums. Results: A total of n = 1016 responses were collected. Approximately 91.6% of the participants were young dentists with y...
Droplet impact on a miscible liquid film finds several applications in scientific and engineering... more Droplet impact on a miscible liquid film finds several applications in scientific and engineering problems. Here, we report that how pre-existing perturbations of a target liquid film, in the form of surface waves, change the impact dynamics and splashing phenomena. For this purpose, we release dyed water droplets and study droplet impact dynamics on a wavy water film, where the waves atop the liquid film are generated by imposing low-frequency two-dimensional (2D) lateral (horizontal) vibrations on glass substrates. Methylene blue-dyed droplet was employed to facilitate the observation of the details of mixing phenomenon given its importance in some applications such as casting homogeneous thin-film coatings. The results are compared with the impact on a quiescent/smooth liquid surface. Splashing is found to be more pronounced for the wavy surface given the additional energy imparted by vibrations and waves. An increase in the crown diameter is also observed for the vibrated wavy liquid film. It is observed that mixing is enhanced significantly in the presence of vibrations and surface waves. The interaction between the pre-existing surface waves and the waves formed after the droplet impact is also studied.
Abstract Pattern-forming instability in various fields is an interesting research topic because o... more Abstract Pattern-forming instability in various fields is an interesting research topic because of its complex physical nature and numerous applications. In this paper, we experimentally study capillary surface waves and patterns formed on a liquid film, cast on a plane substrate without physical walls, but pinned to the substrate edges, and subjected to multi-axis horizontal (lateral) oscillations (55–333 Hz). The effect of single-axis ultrasonic horizontal vibrations (20–170 kHz) was also investigated. We show that using substrates with different geometrical shapes and various travelling paths created by multi-axis vibrations with a phase angle difference between the axes produce a plethora of standing and travelling wave patterns on the liquid film surface. We report perfect standing square and spiral-like patterns for low-frequency multi-axis horizontal vibrations, which are commonly observed for vertical vibrations, while the mechanisms of momentum transfer to the liquid film from the vibrating substrate are different in vertical and horizontal vibrations. Other patterns forming on the liquid film surface in our experiments include lines/stripes, circles, swirls, pentagons, triangles, etc. It is also reported that low-frequency excitations create harmonic travelling waves and standing patterns, while the frequency of response waves generated by the application of ultrasonic horizontal vibrations is several orders of magnitude less than the excitation frequency. No subharmonic cross-waves are observed in this study, which strengthens the idea that plane substrates (without walls) are a good approximation for the theoretical case of a horizontally vibrated liquid film with infinite lateral length.
Changes in temperature regimes, precipitation regimes, and extreme weather events as a result of ... more Changes in temperature regimes, precipitation regimes, and extreme weather events as a result of climate change can cause physiological stress to urban tree species. This study examines the City of Mississauga's urban forest species composition to explore the vulnerability of commonly planted native and non-native species under projected climate change scenarios. A vulnerability matrix was created to highlight the potential vulnerability of species to particular climate Thank you to
Electrical impedance tomography (EIT) has been a hot topic among researchers for the last 30 year... more Electrical impedance tomography (EIT) has been a hot topic among researchers for the last 30 years. It is a new imaging method and has evolved over the last few decades. By injecting a small amount of current, the electrical properties of tissues are determined and measurements of the resulting voltages are taken. By using a reconstructing algorithm these voltages then transformed into a tomographic image. EIT contains no identified threats and as compared to magnetic resonance imaging (MRI) and computed tomography (CT) scans (imaging techniques), it is cheaper in cost as well. In this paper, a comprehensive review of efforts and advancements undertaken and achieved in recent work to improve this technology and the role of artificial intelligence to solve this non-linear, ill-posed problem are presented. In addition, a review of EIT clinical based applications has also been presented.
Journal of artificial organs : the official journal of the Japanese Society for Artificial Organs, 2018
The aim of this work was to analyze a shrouded impeller pediatric ventricular assist device (SIP-... more The aim of this work was to analyze a shrouded impeller pediatric ventricular assist device (SIP-VAD). This device has distinctive design characteristics and parameter optimizations for minimization of recirculation flow and reduction in high-stress regions that cause blood damage. Computational Fluid Dynamics (CFD) simulations were performed to analyze the optimized design. The bench-top prototype of SIP-VAD was manufactured with biocompatible stainless steel. A study on the hydrodynamic and hemodynamic performance of the SIP-VAD was conducted with predictions from CFD and actual experimentation values, and these results were compared. The CFD analysis yielded a pressure range of 29-90 mmHg corresponding to flow rates of 0.5-3 L/min over 9000-11000 rpm. The predicted value of the normalized index of hemolysis (NIH) was 0.0048 g/100 L. The experimental results with the bench-top prototype showed a pressure rise of 30-105 mmHg for the flow speed of 8000-12000 rpm and flow rate of 0.5...
The Primary Care Companion For CNS Disorders, 2016
Despite the numerous advantages of linezolid therapy, one disadvantage continuing to hinder its u... more Despite the numerous advantages of linezolid therapy, one disadvantage continuing to hinder its use is the risk of serotonin syndrome when coadministered with other serotonergic agents. Developing a better understanding of serotonin syndrome is essential for the prevention and management of this potentially life-threatening condition. This report describes a patient with schizophrenia, depression, and severe, acute osteomyelitis. The patient was taking multiple serotonergic agents and required the use of linezolid without the possibility of a sufficient washout period. The severity of the patient's condition in conjunction with increased risk for serotonin syndrome warranted prophylactic treatment with cyproheptadine. The complex pathophysiology of prophylactic treatment of serotonin syndrome with cyproheptadine is worthy of discussion.
We report on the reduction of contact resistance in solution-processed TIPS-pentacene (6,13-bis(t... more We report on the reduction of contact resistance in solution-processed TIPS-pentacene (6,13-bis(triisopropylsilylethynyl)pentacene) and PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]) top-gate bottom-contact organic field-effect transistors (OFETs) by using different contact-modification strategies. The study compares the contact resistance values in devices that comprise Au source/drain electrodes either treated with 2,3,4,5,6-pentafluorothiophenol (PFBT), or modified with an evaporated thin layer of the metal-organic molecular dopant molybdenum tris-[1,2-bis(trifluoromethyl)ethane-1,2-dithiolene] (Mo(tfd)3), or modified with a thin layer of the oxide MoO3. An improved performance is observed in devices modified with Mo(tfd)3 or MoO3 as compared to devices in which Au electrodes are modified with PFBT. We discuss the origin of the decrease in contact resistance in terms of increase of the work function of the modified Au electrodes, Fermi-level pinning effects, and decrease ...
When dynamic load modulation (DLM) based transmitter architecture is used with broadband signals ... more When dynamic load modulation (DLM) based transmitter architecture is used with broadband signals such as Wideband code division multiple access (WCDMA) or Long term evolution (LTE), the envelope signal required to control the load impedance and thus the RF output of PA has very wide bandwidth. It is very difficult to design a transmitter system for such a wideband control signal. In this thesis work, different schemes are investigated for the bandwidth reduction of wideband control signals in Dynamic load modulation (DLM) transmitter architectures. The schemes are implemented using different techniques, based on digital signal processing (DSP) and the simulated results are shown in Matlab. These techniques are capable to reduce the bandwidth of the envelope signal while maintaining high average efficiency of power amplifiers. A single carrier WCDMA signal having bandwidth 3.84 MHz is used as the desired output signal in demonstrating the techniques although the techniques can be well applied to multicarrier signals. The bandwidth of the optimal baseband envelope signal is 12.5 MHz with overall average efficiency of 54%. It is effectively reduced to 4 MHz while retaining high efficiency which is around 49%. The target reduced bandwidth is chosen as 4 MHz to show the effectiveness of the techniques, further in the condition of keeping relatively high average efficiency of PA. Moreover, the efficiency is also compared at different reduced bandwidths for the implemented methods.
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Papers by Talha Khan