76 research outputs found
A possible case of serum sickness after ocrelizumab infusion – Commentary
Serum sickness is a type III delayed hypersensitivity reaction which causes deposition of immune-complexes in the tissues. It has been reported with rituximab, and in this issue of the journal, there is a case report of a patient with relapsing remitting multiple sclerosis who developed a possible serum sickness after the third infusion of ocrelizumab. In this commentary, we discuss the current literature on serum sickness, and how to diagnose and manage it. We provide our opinion on this particular case, and encourage neurologists and patients to remain vigilant of such a possibility
Synthesis and Characterization of New Thioxanthone Derivatives
This work comprises the synthesis of new thioxanthone derivatives containing C-substituted thioxanthone. To obtain these derivatives, the o-mercapto benzoic acid was chosen as the starting material, which was reacted with dry benzene in sulfuric acid (98 %) to produce the thioxanthone (1). The 2,7-(disulfonyl phosphine imine) thioxanthone (4-8) were prepared from reaction of compound (1) with chlorosulfonic acid gave 2,7-(disulfonyl chloride) thioxanthone (2). Treatment of (2) with sodium azide to produce 2,7-(disulfonyl azide) thioxanthone (3). Condensation of (3) with phosphorus compounds afforded compounds (4-8). The 2,7-(disulfonamide) thioxanthone (9-21) was obtained when compound (2) condensed with different aromatic amines, it gave the expected amides (9-21)
A one decade survey of autonomous mobile robot systems
Recently, autonomous mobile robots have gained popularity in the modern world due to their relevance technology and application in real world situations. The global market for mobile robots will grow significantly over the next 20 years. Autonomous mobile robots are found in many fields including institutions, industry, business, hospitals, agriculture as well as private households for the purpose of improving day-to-day activities and services. The development of technology has increased in the requirements for mobile robots because of the services and tasks provided by them, like rescue and research operations, surveillance, carry heavy objects and so on. Researchers have conducted many works on the importance of robots, their uses, and problems. This article aims to analyze the control system of mobile robots and the way robots have the ability of moving in real-world to achieve their goals. It should be noted that there are several technological directions in a mobile robot industry. It must be observed and integrated so that the robot functions properly: Navigation systems, localization systems, detection systems (sensors) along with motion and kinematics and dynamics systems. All such systems should be united through a control unit; thus, the mission or work of mobile robots are conducted with reliability
A nonuniform DPLL architecture for optimized performance
This paper presents the design, analysis, simulation, and implementation of the architecture of a new nonuniform-type digital phase-locked loop (DPLL). The proposed loop uses a composite phase detector (CPD), which consists of a sample-and-hold unit and an arctan block. The CPD improves the system linearity and results in a wider lock range. In addition, the loop has an adaptive controller block, which can be used to minimize the overall system sensitivity to variations in the power of the input signal. Furthermore, the controller has a tuning mechanism that gives the designer the flexibility to customize the loop parameters to suit a particular application. These performance parameters include lock range, acquisition time, phase noise or jitter, and signal-to-noise ratio enhancement. The simulation results show that the proposed loop provides flexibility to optimize the major conflicting system parameters. A prototype of the proposed system was implemented using a field-programmable gate array (FPGA), and the practical results concur with those obtained by simulation using MATLAB/Simulink. © 2013 Institute of Electrical Engineers of Japan.Published versio
Performance evaluation of the time delay digital tanlock loop architectures
This article presents the architectures, theoretical analyses and testing results of modified time delay digital tanlock loop (TDTLs) system. The modifications to the original TDTL architecture were introduced to overcome some of the limitations of the original TDTL and to enhance the overall performance of the particular systems. The limitations addressed in this article include the non-linearity of the phase detector, the restricted width of the locking range and the overall system acquisition speed. Each of the modified architectures was tested by subjecting the system to sudden positive and negative frequency steps and comparing its response with that of the original TDTL. In addition, the performance of all the architectures was evaluated under noise-free as well as noisy environments. The extensive simulation results using MATLAB/SIMULINK demonstrate that the new architectures overcome the limitations they addressed and the overall results confirmed significant improvements in performance compared to the conventional TDTL system
Impact of Post-arrest Care Variation on Hospital Performance After Out-of-hospital Cardiac Arrest
BACKGROUND: Large variation exists for out-of-hospital-cardiac-arrest (OHCA) prehospital care, but less is known about variations in post-arrest care. We sought to evaluate variation in post-arrest care in Texas as well as factors associated with higher performing hospitals.
METHODS: We analyzed data in Texas Cardiac Arrest Registry to Enhance Survival (TX-CARES), including all adult, non-traumatic OHCAs from 1/1/2014 through 12/31/ 2020 that survived to hospital admission. We first evaluated variability in provisions of post-arrest care and outcomes. We then stratified hospitals into quartiles based on their rate of survival and evaluated the association between improving quartiles and care. Lastly, we evaluated for outliers in post-arrest care and outcomes using a mixed-effect regression model.
RESULTS: We analyzed 7,842 OHCAs admitted to 146 hospitals. We identified large variations in post-arrest care, including targeted temperature management (TTM) (IQR 7.0-51.1%), left heart catheterization (LHC) (IQ 0-25%), and percutaneous coronary intervention (PCI) (IQR 0-10.3%). Higher performing hospital quartiles were associated with higher rates of TTM (aOR 1.42, 95% CI 1.36-1.49), LHC (aOR 2.07, 95% CI 1.92-2.23), and PCI (aOR 2.02, 95% CI 1.81-2.25); but lower rates of bystander CPR (aOR 0.90, 95% CI 0.87-0.94). We identified numerous performance outlier hospitals; 39 for TTM, 34 for PCI, 9 for survival to discharge, and 24 for survival with good neurologic function.
CONCLUSIONS: Post-arrest care varied widely across Texas hospitals. Hospitals with higher rates of survival to discharge had increased rates of TTM, LHC, and PCI but not bystander CPR
Diagnosis and management of Neuro-Behçet's disease: international consensus recommendations.
Neuro-Behçet's disease (NBD) is one of the more serious manifestations of Behçet's disease (BD), which is a relapsing inflammatory multisystem disease with an interesting epidemiology. Though NBD is relatively uncommon, being potentially treatable, neurologists need to consider it in the differential diagnosis of inflammatory, infective, or demyelinating CNS disorders. Evidence-based information on key issues of NBD diagnosis and management is scarce, and planning for such studies is challenging. We therefore initiated this project to develop expert consensus recommendations that might be helpful to neurologists and other clinicians, created through an extensive literature review and wide consultations with an international advisory panel, followed by a Delphi exercise. We agreed on consensus criteria for the diagnosis of NBD with two levels of certainty in addition to recommendations on when to consider NBD in a neurological patient, and on the use of various paraclinical tests. The management recommendations included treatment of the parenchymal NBD and cerebral venous thrombosis, the use of disease modifying therapies, prognostic factors, outcome measures, and headache in BD. Future studies are needed to validate the proposed criteria and provide evidence-based treatments
Digital phase lock loops: architectures and applications
Digital phase lock loops are critical components of many communication, signal processing and control systems. This exciting new book covers various types of digital phase lock loops. It presents a comprehensive coverage of a new class of digital phase lock loops called the time delay tanlock loop (TDTL). It also details a number of architectures that improve the performance of the TDTL through adaptive techniques that overcome the conflicting requirements of the locking rage and speed of acquisition. These requirements are of paramount importance in many applications including wireless communications, consumer electronics and others. Digital Phase Lock Loops then illustrates the process of converting the TDTL class of digital phase lock loops for implementation on an FPGA-based reconfigurable system. These devices are being utilized in software-defined radio, DSP-based designs and many other communication and electronic systems to implement complex high-speed algorithms. Their flexibility and reconfigurability facilitate rapid prototyping, on-the-fly upgradeability, and code reuse with minimum effort and complexity. The practical real-time results, of the various TDTL architectures, obtained from the reconfigurable implementations are compared with those obtained through simulations with MATLAB/Simulink. The material in this book will be valuable to researchers, graduate students, and practicing engineers
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