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Cr3+-doped ZnO (CZ) nanoparticles are prepared using hydrothermal and co-precipitation techniques. The desired crystallographic phase of the nanoparticles is confirmed using X-ray diffraction study. Rod-shaped and spherical morphologies of CZ nanoparticles prepared using hydrothermal and co-precipitation techniques were confirmed through FESEM observation. Each type of nanoparticle was taken separately in PVDF to understand the characteristic properties, such as dielectric, piezoelectric, and ferroelectric properties of the resultant CZ-PVDF nanocomposite films. All the nanocomposite films comprising rod-shaped or spherical CZ nanoparticles show butterfly loops with a low leakage current density of 10-5 A m-2 at a maximum electric field of 100 kV m-2 under J-E measurement. These findings suggest that the polarization property of CZ-PVDF nanocomposite films can be obtained at a high external electric field without causing electric breakdown in the samples. Dielectric permittivity as a function of temperature increases with an increase in the loading percentage of both rod-shaped or spherical CZ nanofillers in PVDF. Polarization response also improves with an increase in the loading percentage of CZ nanofillers in PVDF. In particular, the rod-shaped CZ nanofillers in PVDF with a higher loading percentage (CZHP2) result in a maximum polarization of (10 ± 0.29) × 10-4 µC cm-2, remanent polarization of (2 ± 0.04) × 10-4 µC cm-2, and coercive field of (10 ± 0.1) kV cm-1 at a maximum electric field of 50 kV cm-1. The CZHP2 nanocomposite film has a piezoelectric coefficient (d33) of (25 ± 0.24) pC N-1 and a power density of 1278.90 W m-3. These results indicate that the nanocomposite films have potential application in piezoelectric energy harvesters, offering a possible solution to the energy issue faced by modern society.
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Synthesis of diversely functionalized quinoline-2-carboxylates is illustrated through electrochemical cross-dehydrogenative coupling between N-aryl glycinates and methylenecyclopropanes. An extensive range of distinct functionalities is well-compatible under these transition-metal- and oxidant-free mild electrochemical conditions, contributing to a broad substrate scope and practical applicability. Cyclic voltammetric measurements and control experiments suggested a formal [4 + 2] cycloaddition involving radical intermediates, followed by a cyclopropyl ring opening through nucleophilic polar addition, consecutively fabricating C-C and C-N bonds.
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We have devised a supported-amine-catalyzed efficient synthesis of spiro-thiazolone-tetrahydrothiophenes via a sulfa-Michael/aldol cascade approach. The catalyst demonstrated sustained efficacy over 21 cycles. These derivatives were found to exhibit excellent binding abilities with purified human serum albumin as indicated by both in silico and in vitro-based experiments.
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Aminas , Tiofenos , Humanos , Catálisis , Tiofenos/química , Tiofenos/síntesis química , Aminas/química , Aminas/síntesis química , Albúmina Sérica Humana/química , Albúmina Sérica Humana/metabolismo , Unión Proteica , Compuestos de Espiro/química , Compuestos de Espiro/síntesis química , Estructura Molecular , Tiazoles/química , Tiazoles/síntesis química , Simulación del Acoplamiento MolecularRESUMEN
Positive phase coupling plays an attractive role in inducing in-phase synchrony in an ensemble of phase oscillators. Positive coupling involving both amplitude and phase continues to be attractive, leading to complete synchrony in identical oscillators (limit cycle or chaotic) or phase coherence in oscillators with heterogeneity of parameters. In contrast, purely positive phase velocity coupling may originate a repulsive effect on pendulumlike oscillators (with rotational motion) to bring them into a state of diametrically opposite phases or a splay state. Negative phase velocity coupling is necessary to induce synchrony or coherence in the general sense. The contrarian roles of phase coupling and phase velocity coupling on the synchrony of networks of second-order phase oscillators have been explored here. We explain our proposition using networks of two model systems, a second-order phase oscillator representing the pendulum or the superconducting Josephson junction dynamics, and a voltage-controlled oscillations in neurons model. Numerical as well as semianalytical approaches are used to confirm our results.
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The surprising phenomenon of chimera in an ensemble of identical oscillators is no more strange behavior of network dynamics and reality. By this time, this symmetry breaking self-organized collective dynamics has been established in many networks, a ring of non-locally coupled oscillators, globally coupled networks, a three-dimensional network, and multi-layer networks. A variety of coupling and dynamical models in addition to the phase oscillators has been used for a successful observation of chimera patterns. Experimental verification has also been done using metronomes, pendula, chemical, and opto-electronic systems. The phenomenon has also been shown to appear in small networks, and hence, it is not size-dependent. We present here a brief review of the origin of chimera patterns restricting our discussions to networks of globally coupled identical oscillators only. The history of chimeras in globally coupled oscillators is older than what has been reported in nonlocally coupled phase oscillators much later. We elaborate the story of the origin of chimeras in globally coupled oscillators in a chronological order, within our limitations, and with brief descriptions of the significant contributions, including our personal experiences. We first introduce chimeras in non-locally coupled and other network configurations, in general, and then discuss about globally coupled networks in more detail.
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The focal lesion alters the excitation-inhibition (E-I) balance and healthy functional connectivity patterns, which may recover over time. One possible mechanism for the brain to counter the insult is global reshaping functional connectivity alterations. However, the operational principles by which this can be achieved remain unknown. We propose a novel equivalence principle based on structural and dynamic similarity analysis to predict whether specific compensatory areas initiate lost E-I regulation after lesion. We hypothesize that similar structural areas (SSAs) and dynamically similar areas (DSAs) corresponding to a lesioned site are the crucial dynamical units to restore lost homeostatic balance within the surviving cortical brain regions. SSAs and DSAs are independent measures, one based on structural similarity properties measured by Jaccard Index and the other based on post-lesion recovery time. We unravel the relationship between SSA and DSA by simulating a whole brain mean field model deployed on top of a virtually lesioned structural connectome from human neuroimaging data to characterize global brain dynamics and functional connectivity at the level of individual subjects. Our results suggest that wiring proximity and similarity are the 2 major guiding principles of compensation-related utilization of hemisphere in the post-lesion functional connectivity re-organization process.
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Polymer-supported catalysts have emerged as one of the sustainable and cost-effective alternatives in organic synthetic chemistry. We have developed the first polymer-supported DMAP catalyzed one-pot synthesis of diversely substituted α-pyrones. The cascade approach involves C5 conjugate addition of 5H-oxazol-4-ones to α,ß-unsaturated-ß-ketoesters followed by lactonization/elimination.
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Bioactive glass (BG) occupies a significant position in the field of hard and soft tissue regeneration. Different processing techniques and formulas have been introduced to expand their regenerative, angiogenic, and antibacterial properties. In the present study, a new formula of bborosilicate bioactive glass nanofibers was prepared and tested for its wound-healing efficacy in a rabbit animal model. The glass formula ((1-2) mol% of B2O3 (68-69) mol% of SiO2, and (29-30) mol% of CaO) was prepared primarily by the sol-gel technique followed by the electrospinning technique. The material was characterized for its ultrastructure using scanning electron microscopy, chemical composition using FTIR, and its dynamic in vitro biodegradability using ICP-AES. Twelve rabbits were subjected to surgical induction of full-thickness skin defects using a 1 cm2 custom-made stainlessteel skin punch. The bioactive glass nanofibers were used as a grafting material in 6 experimental rabbits, while the defects in the remaining rabbits were considered as the negative control samples. All defects were assessed clinically for the decrease in wound size and clinical signs of healing and histologically for angiogenesis, collagen density, inflammatory response, cell recruitment, epithelial lining, and appendages at 1,2 and 3 weeks following the intervention. Structural analysis of the glass fibers confirmed their nano-size which ranged from 150 to 700 nm. Moreover, the chemical analysis confirmed the presence of SiO2 and B2O3 groups within the structure of the nanofibers. Additionally, dynamic biodegradation analysis confirmed the rapid degradation of the material starting from the first 24 h and rapid leaching of calcium, silicon, and boron ions confirming its bioactivity. The wound healing study of the nanofibrous scaffold confirmed its ability to accelerate wound healing and the closure rate in healthy rabbits. Histological analysis of the defects confirmed the angiogenic, regenerative and antibacterial ability of the material throughout the study period. The results unveil the powerful therapeutic properties of the formed nanofibers and open a new gate for more experimental and clinical applications.
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The developed methodology describes an environmentally benign protocol for electro-oxidative CF3-radical generation, followed by cascade cyclization fabricating an isoxazoline scaffold from a ß,γ-unsaturated oxime. Consecutive C-O and C-C bond formations were achieved through this method featuring mild, robust, and scalable reaction conditions and broad substrate scope. Mechanistic studies revealed the necessity of anodic oxidation for the cascade process. Further conversion of the isoxazoline afforded other valuable derivatives.
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Humans drive in a holistic fashion which entails, in particular, understanding dynamic road events and their evolution. Injecting these capabilities in autonomous vehicles can thus take situational awareness and decision making closer to human-level performance. To this purpose, we introduce the ROad event Awareness Dataset (ROAD) for Autonomous Driving, to our knowledge the first of its kind. ROAD is designed to test an autonomous vehicle's ability to detect road events, defined as triplets composed by an active agent, the action(s) it performs and the corresponding scene locations. ROAD comprises videos originally from the Oxford RobotCar Dataset, annotated with bounding boxes showing the location in the image plane of each road event. We benchmark various detection tasks, proposing as a baseline a new incremental algorithm for online road event awareness termed 3D-RetinaNet. We also report the performance on the ROAD tasks of Slowfast and YOLOv5 detectors, as well as that of the winners of the ICCV2021 ROAD challenge, which highlight the challenges faced by situation awareness in autonomous driving. ROAD is designed to allow scholars to investigate exciting tasks such as complex (road) activity detection, future event anticipation and continual learning. The dataset is available at https://github.com/gurkirt/road-dataset; the baseline can be found at https://github.com/gurkirt/3D-RetinaNet.
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The demand for novel and improved medicine from biological sources to cater to the biopharmaceutical sector has increased significantly in recent years. Among the vast and miscellaneous microbial diversity, fungi provide a prolific source of structurally unique and biologically active secondary metabolites. Natural products obtained from fungi have reformed the era of biomedicine, providing effective drugs that have diverse healing potential. In this review, we focus on the isolation, chemical structure, and bioactivity of biomolecules that have been identified and studied for the first time. Further, we also explain in substantial detail that how the vast uninvestigated Emericellopsis and Simplicillium species may serve as a potential treasure trove of chemically diverse compounds.
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Productos Biológicos , Hypocreales , Productos Biológicos/farmacología , Productos Biológicos/químicaRESUMEN
A simple model on volatile organic compound (VOC)-mediated plant-insect interactions is proposed and examined here, when two different classes of herbivorous insects competing for a common resource (plant) in the presence of a specialist carnivorous enemy, which only predates one of the herbivore species. We, particularly, emphasize the impact of VOCs on plant's growth fitness. The system experiences several local and global bifurcations with emergent alternative states for variations in recruitment factors and predation rate. Basin transitions and basin of attractions have provided detail descriptions on the selectivity of the alternative states, when only one of the herbivore species can survive depending on the choice of initial population densities of the interacting species and how it provides a steady growth in plant. Additionally, our results support the concept of competitive exclusion principle in an indirect interspecific competition between the two herbivore types for the common resource, plant.
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Herbivoria , Compuestos Orgánicos Volátiles , Animales , Insectos , Conceptos Matemáticos , PlantasRESUMEN
We present an exemplary system of three identical oscillators in a ring interacting repulsively to show up chimera patterns. The dynamics of individual oscillators is governed by the superconducting Josephson junction. Surprisingly, the repulsive interactions can only establish a symmetry of complete synchrony in the ring, which is broken with increasing repulsive interactions when the junctions pass through serials of asynchronous states (periodic and chaotic) but finally emerge into chimera states. The chimera pattern first appears in chaotic rotational motion of the three junctions when two junctions evolve coherently, while the third junction is incoherent. For larger repulsive coupling, the junctions evolve into another chimera pattern in a periodic state when two junctions remain coherent in rotational motion and one junction transits to incoherent librational motion. This chimera pattern is sensitive to initial conditions in the sense that the chimera state flips to another pattern when two junctions switch to coherent librational motion and the third junction remains in rotational motion, but incoherent. The chimera patterns are detected by using partial and global error functions of the junctions, while the librational and rotational motions are identified by a libration index. All the collective states, complete synchrony, desynchronization, and two chimera patterns are delineated in a parameter plane of the ring of junctions, where the boundaries of complete synchrony are demarcated by using the master stability function.
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INTRODUCTION: Nowadays, the co-infection of different classes of pathogens is a major concern. The objective of this study was to develop a successful therapy for keratitis caused by the co-infection of Candida sp. with Pseudomonas sp, which is difficult to cure. The study is based on a 47 years old male farmer showing redness and watering in the right eye for 15-days. ; Methods: The microbiological examination was performed to isolate the causative organisms, i.e. Pseudomonas aeruginosa and Candida albicans. They were cultured separately along with their co-culture and treated with ciprofloxacin and amphotericin B during the growing stage to predict a definite cure. ; Results: Scanning electron microscope (SEM) results confirmed the inter-specific interaction between the two different types of microorganisms. Amphotericin-B and Ciprofloxacin showed the least MIC value for both organisms in co-culture. ; Conclusion: Treatment with Amphotericin-B and 5% ciprofloxacin effectively hindered the growth of Pseudomonas aeruginosa and Candida albicans, the co-infection of which caused keratitis. This therapy may be successfully implied for such cases of co-infection in the future.
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Coinfección , Queratitis , Anfotericina B , Candida albicans , Humanos , Masculino , Persona de Mediana Edad , Pseudomonas aeruginosaRESUMEN
We investigate spreading and recovery of disease in a square lattice, and, in particular, emphasize the role of the initial distribution of infected patches in the network on the progression of an endemic and initiation of a recovery process, if any, due to migration of both the susceptible and infected hosts. The disease starts in the lattice with three possible initial distribution patterns of infected and infection-free sites, viz., infected core patches (ICP), infected peripheral patches (IPP), and randomly distributed infected patches (RDIP). Our results show that infection spreads monotonically in the lattice with increasing migration without showing any sign of recovery in the ICP case. In the IPP case, it follows a similar monotonic progression with increasing migration; however, a self-organized healing process starts for higher migration, leading the lattice to full recovery at a critical rate of migration. Encouragingly, for the initial RDIP arrangement, chances of recovery are much higher with a lower rate of critical migration. An eigenvalue-based semianalytical study is made to determine the critical migration rate for realizing a stable infection-free lattice. The initial fraction of infected patches and the force of infection play significant roles in the self-organized recovery. They follow an exponential law, for the RDIP case, that governs the recovery process. For the frustrating case of ICP arrangement, we propose a random rewiring of links in the lattice allowing long-distance migratory paths that effectively initiate a recovery process. Global prevalence of infection thereby declines and progressively improves with the rewiring probability that follows a power law with the critical migration and leads to the birth of emergent infection-free networks.
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Background: Poly(lactic-co-glycolic) acid nanoparticle (PLGA-NP) trafficking across cell membranes was investigated to confirm preliminary results that contradicted existing studies. Materials & methods: Uptake and retention of PLGA-NPs at 37 and 4°C in the presence and absence of metabolic inhibitors in various cell lines was estimated. Results: Pulse experiments with metabolic inhibitors and culturing at 4°C demonstrated the predominantly passive nature of PLGA-NP uptake. Chase experiments with metabolic inhibitors indicated the role of active exocytosis in the extrusion of these NPs. PLGA-NPs with ionic or nonionic hydrophilic coats with highly positive or negative ζ-potential also showed similar results. Conclusion: Our study opens up the possibility of modulation of active exocytosis to increase intracellular retention of NPs for an extended period of drug delivery.
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Nanopartículas , Neoplasias , Línea Celular , Portadores de Fármacos , Ácido Láctico , Neoplasias/tratamiento farmacológico , Tamaño de la Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido PoliglicólicoRESUMEN
Acute interface infectious keratitis (AIIK) is a rare and devastating complication following lamellar keratoplasty. Here, we report a case of AIIK following deep anterior lamellar keratoplasty (DALK) caused by double gram-negative bacilli and required urgent therapeutic penetrating keratoplasty (TPK). Microbiology revealed co-infection with Klebsiella and E. Coli sensitive only to colistin. Donor rim culture also grew Klebsiella. TPK was successful in controlling the infection and the patient responded to topical fortified amikacin and ciprofloxacin. Since optical quality tissue was used, the patient regained 20/40 vision postoperatively. This report highlights that immediate TPK and intense antimicrobial therapy can salvage these eyes with good visual outcome.
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Trasplante de Córnea , Queratitis , Escherichia coli , Humanos , Queratitis/diagnóstico , Queratitis/tratamiento farmacológico , Queratitis/etiología , Queratoplastia Penetrante/efectos adversos , KlebsiellaRESUMEN
BACKGROUND: Colistin was considered as the most effective antibiotic against Acinetobacter baumannii, a widely-known opportunistic pathogen. In recent years, a number of colistin resistant strains have also been reported. OBJECTIVE: This work is commenced to investigate the contribution of efflux pumps toward resistance to colistin-like cyclic polypeptide antibiotics, since the efflux pumps serve as the escape routes leading to drug-resistance. METHODS: RNA was extracted from A. baumannii isolates cultured from samples procured by tracheal aspiration of infected patients. The expressions of gene(s) that played major roles in the regulation of efflux pump families and involvement of integron systems were studied using real time PCR. Antimicrobial susceptibility tests were conducted to investigate antibiotic resistance of the isolates. RESULTS: It was observed that genes coding for sugE, ydhE, ydgE, mdfA, ynfA and tolC significantly contributed to resistance against colistin antibiotics, however, no significant transcriptional change was observed in the efflux pump, MexAB-OprM. Results suggest that A. baumanii readily pumps out colistin via efflux pumps belonging to MATE and SMR family. CONCLUSION: Integral role of efflux pumps and integron 1 genetic system was elucidated towards evolution of multi-drug resistant strain(s). Therefore, for accurate therapeutics, an early detection of efflux genes is crucial before prescribing against colistin resistant A. baumanii.
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Infecciones por Acinetobacter/diagnóstico , Acinetobacter baumannii/aislamiento & purificación , Colistina/farmacología , Farmacorresistencia Bacteriana , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/genética , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Humanos , Paracentesis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Regulación hacia ArribaRESUMEN
A haemocholecyst is a clot-filled gallbladder caused by bleeding into its lumen. It is a rare entity with fewer than 50 cases reported in the English literature. Preoperative diagnosis is often not possible even with good quality cross-sectional imaging. Here, we present a case of a gallbladder mass, whose nature was only made clear at operation, where a hugely enlarged gallbladder was found filled with blood clots. There was neither liver infiltration nor regional lymphadenopathy. The clinical status of the patient demanded simple cholecystectomy. Histopathological examination, however, revealed a gallbladder adenocarcinoma, infiltrating the perimuscular connective tissue. Thus, more radical surgery was performed eight weeks later. At the 21-month follow-up, the patient was found to be well.
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Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Neoplasias de la Vesícula Biliar/diagnóstico , Neoplasias de la Vesícula Biliar/patología , Adenocarcinoma/cirugía , Colecistectomía , Femenino , Neoplasias de la Vesícula Biliar/cirugía , Hematoma/diagnóstico , Hematoma/patología , Hematoma/cirugía , Humanos , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
A hydrolytic transformation study was conducted in water of pH 4.0, 7.0 and 9.2 to evaluate the effect of pH on persistence of a new readymix formulation of fomesafen and quizalofop-ethyl. The water samples were fortified at 0.5 and 1 µg mL-1 levels and analysed at 0 (2 h), 1, 3, 7, 15, 30, 60, 90, 120, 150 days interval. Both the analytical methods were validated following SANTE guideline and found accurate based on average recovery of 80-100%, Relative standard deviation (RSD) < 20% and Coefficient of Determination (R2) 0.99. The dissipation of both the molecules was pH dependent and followed first order kinetics. Higher persistence of fomesafen was observed in alkaline pH as compared to neutral and acidic pH with half-life of 41.56-63.24 days, whereas higher stability of quizalofop-ethyl was observed in the water of acidic pH followed by neutral and alkaline pH with half-life of 1.26-8.09 days.