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1.
Chempluschem ; : e202400018, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446710

RESUMO

Organic memory devices have attracted attention because they promise flexible electronics, low manufacturing costs, and compatibility with large-scale integration. A series of new D-A architectures were synthesized employing different donor groups and the isatin moiety as the acceptor through Suzuki-Miyaura coupling reactions. Strong intramolecular interactions were observed in the synthesized compounds, further corroborated by an optimal bandgap. The SEM investigation confirmed good molecular ordering and superior thin film surface coverage. All the compounds demonstrated notable binary Write-Once-Read-Many-Times (WORM) memory behaviour. The threshold switching voltage for these D-A systems ranged from -0.79 to -2.37 V, with the compound having isobutyl substituent showing the lowest threshold voltage and maximum ON/OFF ratio of 102, thus outperforming others. The combined effects of charge transfer and charge trapping are responsible for the resistive switching mechanism prevailing in these systems. The alterations in D-A molecules that affect molecular packing, thin film morphology, and, finally, the memory performance of the active layer are highlighted in this work.

2.
Chemphyschem ; 25(9): e202400003, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38372587

RESUMO

Donor-acceptor (D-A)-based architecture has been the key to increase storage capability efficiency through the enhanced charge transportation in the fabricated device. We have designed and synthesized a series of functionalized indoloquinoxalines (IQ) for non-volatile organic memory devices. The investigation on UV-visible spectra reveals the absorption maxima of the compounds around 420 nm, attributed to the intramolecular charge transfer between indole and quinoxaline moiety. The irreversible anodic peak in the 1.0 to 1.5 V range indicates the indole moiety's oxidation ability. Besides, the cathodic peak in the range of -0.5 to -1.0 V, contributed to the stability of the reduced quinoxaline unit. All the compounds exhibited uniformly covered thin film in SEM analysis, potentially facilitating the seamless charge carrier migration between adjacent molecules. The methoxyphenyl substituted compound exhibited the binary write-once read-many (WORM) memory behavior with the lowest threshold voltage of -0.81 V. The molecular simulations displayed the efficient intramolecular charge transfer, providing the fabricated device's distinctive conductive states. Except for the tert-butylphenyl compound, which showed volatile dynamic random-access memory (DRAM) behavior, all the other compounds exhibited non-volatile WORM memory behavior, suggesting IQs potential as an intrinsic D-A molecule in organic memory devices on further structural refinement.

3.
Biomed Res Int ; 2022: 7799812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480141

RESUMO

Brain cancer is one of the cell synthesis diseases. Brain cancer cells are analyzed for patient diagnosis. Due to this composite cell, the conceptual classifications differ from each and every brain cancer investigation. In the gene test, patient prognosis is identified based on individual biocell appearance. Classification of advanced artificial neural network subtypes attains improved performance compared to previous enhanced artificial neural network (EANN) biocell subtype investigation. In this research, the proposed features are selected based on improved gene expression programming (IGEP) with modified brute force algorithm. Then, the maximum and minimum term survivals are classified by using PCA with enhanced artificial neural network (EANN). In this, the improved gene expression programming (IGEP) effectual features are selected by using remainder performance to improve the prognosis efficiency. This system is estimated by using the Cancer Genome Atlas (CGA) dataset. Simulation outputs present improved gene expression programming (IGEP) with modified brute force algorithm which achieves accurate efficiency of 96.37%, specificity of 96.37%, sensitivity of 98.37%, precision of 78.78%, F-measure of 80.22%, and recall of 64.29% when compared to generalized regression neural network (GRNN), improved extreme learning machine (IELM) with minimum redundancy maximum relevance (MRMR) method, and support vector machine (SVM).


Assuntos
Neoplasias Encefálicas , Redes Neurais de Computação , Algoritmos , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Simulação por Computador , Humanos , Máquina de Vetores de Suporte
4.
ISA Trans ; 104: 233-244, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32414560

RESUMO

A hybrid technique for improving the transient and small signal stability in microgrid (MG) using virtual inertia is discussed at these manuscripts. The established hybrid method denotes combined performance of both Whale Optimization Algorithm (WOA) and Ant Lion Optimization (ALO) algorithm it is named as AWOALO technique. The purpose of AWOALO technique is to optimize the control parameters for regulate the changes occurred in the grid parameter such as voltage as well as frequency depend on variations of inertia. AWOALO technique is performed to optimally adjust the parameters to have a smooth transition behind a change or disturbance. Here, the Virtual Synchronous Generator denotes control method to inverter depend on generator units, which uses a synchronous generator (SG) enhance system stability. WOA is performed to adjust the parameters of VSG units to attain the objective function. The searching behaviour of WOA is modified by the hunting behaviour of ALO. This hunting behaviour of ALO is used to achieve the objective function with less computational complexity. The AWOALO technique with the VSG control scheme ensures the smooth response, accurate performance while considering the constraints of voltage angle deviation The AWOALO method is actualized at MATLAB/Simulink working platform as well as outcomes are examined to two test cases and compared with various solution techniques such as base method, ant lion optimization (ALO) and whale optimization algorithm (WOA). The comparison outcomes determine the superiority of AWOALO method as well as confirm its potential to resolve problem. Finally, AWOALO technique display promising presentation based on shared power, that is, 100% power is deliver as VSG units compared to base, ALO, and WOA; however, the frequency and the deviation in frequency response due to dynamic condition is not encouraging.

5.
ScientificWorldJournal ; 2015: 596138, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26504898

RESUMO

Wireless sensor network is widely used to monitor natural phenomena because natural disaster has globally increased which causes significant loss of life, economic setback, and social development. Saving energy in a wireless sensor network (WSN) is a critical factor to be considered. The sensor nodes are deployed to sense, compute, and communicate alerts in a WSN which are used to prevent natural hazards. Generally communication consumes more energy than sensing and computing; hence cluster based protocol is preferred. Even with clustering, multiclass traffic creates congested hotspots in the cluster, thereby causing packet loss and delay. In order to conserve energy and to avoid congestion during multiclass traffic a novel Priority Based Congestion Control Dynamic Clustering (PCCDC) protocol is developed. PCCDC is designed with mobile nodes which are organized dynamically into clusters to provide complete coverage and connectivity. PCCDC computes congestion at intra- and intercluster level using linear and binary feedback method. Each mobile node within the cluster has an appropriate queue model for scheduling prioritized packet during congestion without drop or delay. Simulation results have proven that packet drop, control overhead, and end-to-end delay are much lower in PCCDC which in turn significantly increases packet delivery ratio, network lifetime, and residual energy when compared with PASCC protocol.

6.
J Clin Neuromuscul Dis ; 14(4): 176-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23703012

RESUMO

Facial onset sensory motor neuronopathy (FOSMN) is a recently identified condition characterized initially by trigeminal sensory involvement followed by sensory propagation and motor neuronopathy. Few cases have been reported, and latest evidence points toward a neurodegenerative cause. We describe a 59-year-old female who presented a typical clinical picture of FOSMN over 10 years. Immunological investigations showed positive antinuclear antibodies and antibodies to extractable nuclear antigens (anti-Ro antibodies). A mild inflammatory infiltrate was found on salivary gland biopsy. Intravenous immunoglobulin therapy was effective in improving and then stabilizing this patient's condition. The pathophysiology of FOSMN remains uncertain, and this condition may be heterogeneous. An immune basis cannot be discounted in any given case, and suspected cases merit a trial of immunotherapy.


Assuntos
Doenças do Nervo Facial/imunologia , Doenças do Nervo Facial/terapia , Imunoglobulinas Intravenosas/uso terapêutico , Ribonucleoproteínas/imunologia , Feminino , Humanos , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade
8.
Arch Microbiol ; 191(6): 529-41, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19415238

RESUMO

In Zymomonas mobilis, the extracellular levansucrase (SacB) and extracellular sucrase (SacC) are involved in sucrose hydrolysis. Genes coding for these two enzymes (sacB and sacC) are arranged in a cluster in the genome and separated by a short intervening sequence. The level of sacC transcript was 12-fold higher than that of sacB transcript. On the other hand, transcript stability analysis in sucrose grown cultures revealed that the half-life of the sacB transcripts (153 s) was more than twofold higher than that of sacC transcript (66 s). The decay curves of sacB and sacC transcripts analyzed by the semi-quantitative RT-PCR correlated well with the decay curves of the respective enzyme activities. In the sacB promoter disruption mutant, Z. moblis BT2, the extracellular sucrase activity decreased from 2.6 to 2.0 U mg(-1) in sucrose medium due to the loss of SacB expression. The expression of sacC in the absence of the sacB promoter suggested that these two genes could be transcribed as different mRNAs. The promoter-lacZ fusion studies in Escherichia coli proved that the short intervening region acts as a strong promoter for the sacC gene.


Assuntos
Proteínas de Bactérias/genética , Hexosiltransferases/genética , Regiões Promotoras Genéticas , Estabilidade de RNA , Sacarase/genética , Zymomonas/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Hexosiltransferases/metabolismo , Dados de Sequência Molecular , Família Multigênica , Conformação de Ácido Nucleico , RNA Bacteriano/metabolismo , Sacarase/metabolismo , Zymomonas/enzimologia
9.
J Appl Microbiol ; 96(4): 671-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15012804

RESUMO

AIMS: Disruption of the extracellular Zymomonas mobilis sucrase gene (sacC) to improve levan production. METHODS AND RESULTS: A PCR-amplified tetracycline resistance cassette was inserted within the cloned sacC gene in pZS2811. The recombinant construct was transferred to Z. mobilis by electroporation. The Z. mobilis sacC gene, encoding an efficient extracellular sucrase, was inactivated. A sacC defective mutant of Z. mobilis, which resulted from homologous recombination, was selected and the sacC gene disruption was confirmed by PCR. Fermentation trials with this mutant were conducted, and levansucrase activity and levan production were measured. In sucrose medium, the sacC mutant strain produced threefold higher levansucrase (SacB) than the parent strain. This resulted in higher levels of levan production, whilst ethanol production was considerably decreased. CONCLUSIONS: Zymomonas mobilis sacC gene encoding an extracellular sucrase was inactivated by gene disruption. This sacC mutant strain produced higher level of levan in sucrose medium because of the improved levansucrase (SacB) than the parent strain. SIGNIFICANCE AND IMPACT OF THE STUDY: The Z. mobilis CT2, sacC mutant produces high level of levansucrase (SacB) and can be used for the production of levan.


Assuntos
Frutanos/biossíntese , Genes Bacterianos , Mutagênese Insercional/métodos , Sacarase/genética , Zymomonas/genética , Meios de Cultura , Eletroporação , Etanol/metabolismo , Fermentação , Glucose/metabolismo , Hexosiltransferases/biossíntese , Resistência a Tetraciclina/genética , Zymomonas/metabolismo
10.
Rev Sci Tech ; 23(3): 943-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15861890

RESUMO

An outbreak of sheep pox occurred in December 2001 on a sheep breeding farm in Jammu, India. The farm maintains three exotic breeds of sheep, i.e. American Merino, Rambouillet and Australian cross. The disease agent was confirmed as sheep pox virus by clinical and post-mortem examination as well as laboratory testing. Typical pock lesions were dispersed over the body of the affected animals with nodular lesions observed in the lung tissue of the dead animals. Sheep pox virus antigen and antibody were detected in infected tissue and convalescent sera, respectively, with serological tests. Viral deoxyribonucleic acid was extracted from the infected tissue and amplified using a diagnostic polymerase chain reaction. Sheep of the Rambouillet breed were found to be most susceptible to infection with morbidity and mortality rates of 26.9% and 8.3%, respectively. Morbidity and mortality rates in the entire flock were 18.4% and 6.3%, respectively. The grazing and migration pattern indicates that the disease was probably introduced to the farm by local sheep.


Assuntos
Cruzamento/métodos , Capripoxvirus/imunologia , Surtos de Doenças/veterinária , Infecções por Poxviridae/veterinária , Doenças dos Ovinos/epidemiologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/análise , Capripoxvirus/genética , Contraimunoeletroforese/veterinária , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Índia/epidemiologia , Masculino , Reação em Cadeia da Polimerase/veterinária , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/mortalidade , Infecções por Poxviridae/patologia , Ovinos , Doenças dos Ovinos/mortalidade , Doenças dos Ovinos/patologia
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