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The self‐assembly of the π‐conjugated 1,4‐di(1H‐imidazol‐1‐yl)benzene (dib) and 4,4′‐di(1H‐imidazol‐1‐yl)‐1,1′‐biphenyl (dibp) ligands together with 4′‐(3,4‐ dicarboxylphenyloxy)‐4‐biphenylcarboxylic acid (H3L) reacts with metal Zn (II) salts to construct two new coordination polymers (CPs), namely [Zn (dib)(HL)(H2O)] (1) and [Zn (dibp)(HL)] (2). Fluorescence measurements reveal that 1 and 2 could display a highly sensitive fluorescence response toward Hg2+ and nitrofurazone (NFZ). Fluorescence investigations suggest that 1 and 2 are promising multi‐responsive sensing materials for detecting Hg2+ and NFZ through fluorescence quenching (turn‐off). The limits of detection toward Hg2+ ions are 0.221 μM and 0.124 μM, while the limits of detection toward NFZ are 0.757 μM and 0.960 for 1 and 2, respectively. Interestingly, these Hg2+ and NFZ selective sensing processes can even be completed by the reusable CPs detected by the naked eyes. Hirshfeld surfaces and fingerprint plots are extensively used to investigate intermolecular interactions, which play a crucial role in creating diverse supramolecular designs that can be compared. [ABSTRACT FROM AUTHOR]

The heart's significant contribution is well known in the functioning of the human body. If it stops operating, the body shuts down systematically, which is known as cardiac arrest. The heart acts as a power supply that generates the electrical pulses which run through the entire body to supply energy to every organ. But in today's time, due to our unhealthy lifestyle, the functioning of the heart gets uneven, that it is unable to supply the regulated electrical pulses. This irregular supply of electrical pulses is known as arrhythmia. In order to overcome arrhythmia, the medical device pacemaker is invented to control the irregularities of the heart rate. The pacemaker generates the electrical pulses artificially when the heart is unable to respond at regular intervals. Many researchers have proposed several control techniques using PID controllers to improve the performance of such device called as artificial pacemaker. In this work an optimized system is designed for an artificial cardiac pacemaker to well perform so that the system can generate a controlled desire response through the incorporation of both integer and fractional order PID controller for better system performance with least errors. The applied integer and fractional order PID controllers are tuned using various classical tuning methods and the modern optimization technique such as particle swarm optimization (PSO) method to obtain a response with better dynamic and static performance. These implemented tuning methods offer a good control characteristic for the pacing rate of the cardiac pacemaker. [ABSTRACT FROM AUTHOR]

The solvothermal reaction of Ln(NO3)3•6H2O (Ln = Nd, Sm, Eu, Tb, and Dy) with 9,10-bis(4-carboxylatopyridinium-1-methylene)anthracene dibromide (H2L)Br2 resulted in the formation of an isostructural series of lanthanide-based metal organic frameworks (Ln-MOFs), {[Nd(L)3/2(H2O)2]·(NO3)3·(S)}n (1), {[Sm(L)3/2(H2O)2]·(NO3)3·(S)}n (2), {[Eu(L)3/2(H2O)2]·(NO3)3·(S)}n (3), {[Tb(L)3/2(H2O)2]·(NO3)3·(S)}n (4) and {[Dy(L)3/2(H2O)2]·(NO3)3·(S)}n (5), where S denotes squeezed disordered solvent molecules and out of three nitrate ions in the voids, one nitrate is squeezed due to the high disorder. These MOFs were characterized with various techniques and single crystal X-ray analysis revealed a three dimensional (3D) (4,4,6)-connected metal organic framework with mononuclear metallic nodes in bicapped trigonal prismatic geometry. From the present series, we selected {[Sm(L)3/2(H2O)2]·(NO3)3·(S)}n (2) as a representative example for structural description and gas adsorption study whereas {[Dy(L)3/2(H2O)2]·(NO3)3·(S)}n (5) was used for the sensing of nitro compounds. All MOFs showed stability up to 200 °C. 2 demonstrates a higher CO2 uptake, despite exhibiting a low specific surface area (SABET) in N2 sorption studies. The sensing result shows that 5 act as selective sensors towards TNP with quenching efficiency greater than 99%. [ABSTRACT FROM AUTHOR]

Background: Rhinocerebral mucormycosis is an acute, fulminant, and often lethal opportunistic infection1. It is caused by one of the members of the mucoraceal family, including Absidia, Mucor, and Rhizopus2 It occurs only when immunity is critically low, likely uncontrolled diabetes, post transplant and immunocompromised patients. Clinically, presenting symptoms are nonspecific including headache, nasal blockage, nasal discharge and crusting, low-grade fever, facial swelling with loss of sensation of face, and orbital or paranasal sinus syndrome. After infection of the nasal cavity and paranasal sinuses, the fungi cause a necrotizing vasculitis that extends rapidly into deep face, orbits, cranial cavity, and brain through skull base partitions and foramina2. When limited involvement of the paranasal sinuses is present, survival rates are between 50% and 80% . However, when brain invasion has occurred, mortality is greater than 80%. Because of its lethal nature, it must be recognized early and treated aggressively. We retrospectively reviewed the neuroimaging findings in a series of ten patients with rhinocerebral mucormycosis to establish common radiographic patterns that may be useful in predicting the diagnosis of this infection. Material and methods We evaluated the imaging and clinical data of 19 males and 11 females, 26 to 81 years old, with mucormycosis of the craniofacial areas. Patients were selected for study if the diagnosis of mucormycosis was established by means of culture, biopsy, and magnetic resonance (MR) images or computed tomography (CT) scans were available for review. Twenty eight patients were immunosuppressed. Twenty six patients had history of diabetes mellitus, and five had hematologic conditions and concomitant immunocompromised states. All patients had MR imaging with a 1.5-T system. Both T1- and T2-weighted images were obtained as well as T1- weighted images after intravenous injection of gadopentetate dimeglumine (0.1 mmol/kg).Nine patients had CT scans available for review, fifteen patients had MRI scans available for review, six patients had both CT and MRI available. Images were then evaluated for density, signal intensity, and contrast enhancement characteristics. The CT density was evaluated in non-enhanced images and compared with muscle/brain. The MR signal intensity was compared with gray matter on the T1- and T2-weighted images. Image interpretation The sinuses showing opacification on CT or MRI were recorded in each case. Any complications like arterial thrombosis were noted on CT and MRI. Presence of bone involvement was evaluated on the CT. The appearance on plain T1 and T2 images were documented. On post contrast CT and MRI, the type of contrast enhancement and involvement of any extra sinus structures including orbit, retro-orbital fat, optic nerve, facial muscles, pterygopalatine fossa, masticator space, brain and cavernous sinus were noted. Cavernous sinus with internal carotid artery involvement was visualised as thickening and non enhancement on post contrast scans with presence of abnormal surrounding soft tissue. Fat stranding and soft tissue extension similar in appearance to the intrasinus soft tissue was taken as evidence of orbital, retroantral, masticator and pterygopalatine involvement. Orbital cellulitis was seen as stranding in the retrobulbar fat. Patients with intracranial extension were evaluated for presence of extradural collections, dural enhancement, infarcts, cerebritis and intracerebral abscess. Results A total of 30 patients with rhinocerebral mucormycosis having preoperative contrast CT and/or MRI imaging and histopathology confirmation were identified. Out of 30, nine patients underwent contrast-enhanced CT examination, 14 patients had MRI available, 7 patients had both CT and MRI. [ABSTRACT FROM AUTHOR]

Background - Undoubtedly, the end of 2019 will be recorded as one of the most sinister times in the history of medicine, when an outbreak of fatal pneumonia caused by a novel coronavirus. RT-PCR test may show false negativity due to various reasons. Studies have shown that chest CT has a high sensitivity for the diagnosis of COVID-19. Objectives: The main objective of this study was to determine the computed tomography findings in the patients presenting with COVID-19 like symptoms, to study the biochemical and inflammatory marker profile of patients presenting with COVID-19 like symptoms and to establish correlation of all the above parameters and CT severity score. Methods: 100 cases who presented with COVID-19 like symptoms and were COVID-19 RT- PCR negative in a tertiary care center were included in the study. Patients have undergone various lab investigations like CRP; D-dimer; IL-6 and Serum Ferritin. HRCT were done for all the 100 patients. Results: In our study, highest number of patients belong to 51 to 60 years and 71 to 80 years age group i.e., 22 each. Majority of patients in our study are male i.e.,74% and females are 26%. The most common finding was ground glass opacities followed by consolidation on HRCT. There is statistically significant difference in mean value of various biochemical markers like CRP, S. ferritin, IL-6 and D-Dimer and CT severity score. We found that D- dimer is the best predictor for outcome of the patients followed by S. ferritin, CRP and HRCT thorax. Conclusion: Chest CT can serve as a superior screening tool to RT-PCR. Increase in severity of disease as evident by higher CT score leads to increase in value of various inflammatory and bio chemical markers. [ABSTRACT FROM AUTHOR]