The estimation of spatial signatures and spatial frequencies is crucial for several practical applications such as radar, sonar, and wireless communications. In this paper, we propose two generalized ...iterative estimation algorithms to the case in which a multidimensional (R-D) sensor array is used at the receiver. The first tensor-based algorithm is an R-D blind spatial signature estimator that operates in scenarios where the source’s covariance matrix is nondiagonal and unknown. The second tensor-based algorithm is formulated for the case in which the sources are uncorrelated and exploits the dual-symmetry of the covariance tensor. Additionally, a new tensor-based formulation is proposed for an L-shaped array configuration. Simulation results show that our proposed schemes outperform the state-of-the-art matrix-based and tensor-based techniques.
Glyphosate is the most widely used broad-spectrum agrochemical, particularly due to its non-selective action mechanism. However, there are concerns regarding its use and possible threat to aquatic ...and terrestrial lifeforms and the environment. This article aims to better understand the effect of pH on the structural, spectroscopic, and physicochemical properties of glyphosate-based structures, as well as its degradation and respective intermediates.
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•A discrepancy of lipophilicity between the theoretical models in basic medium.•Zwitterions show a high lipophilic character in basic medium.•Insights into the degradation from a theoretical mass spectrometry approach.•Solvent has a considerable effect on the chemical shifts of zwitterions.•The spectroscopic properties can be used to describe the structures of zwitterions.
Glyphosate is the most used broad-spectrum agrochemical due to its non-selective action mechanism. However, there are concerns regarding being a threat to aquatic and terrestrial lifeforms and the environment. In this study, we conducted a systematic theoretical investigation of the effect of pH on the electronic structure, physicochemical, and spectroscopic properties (IR, Raman, UV–vis, ECD, EI-MS, and NMR) of glyphosate and its zwitterionic structures. The lipophilicity of the zwitterions was studied with ADMET and DFT, and a significant discrepancy between the models was observed. Theoretical EI-MS provided insights into the degradation pathways and possible intermediates. The effect of protonation and hydration on the magnetic properties was described based on an implicit-explicit strategy to compute NMR chemical shifts for the zwitterions, in which the solvent has a considerable effect on the chemical shifts. Overall, our findings suggest that spectroscopic properties can be used to describe glyphosate-based zwitterionic structures.
This study evaluated the effects of local application of autologous platelet-rich plasma (PRP) on the tooth extraction site of rats presenting the main risk factors for medication-related ...osteonecrosis of the jaw (MRONJ). For seven weeks, senile rats were submitted to systemic treatment with vehicle (VEH and VEH-PRP) or 100 μg/Kg of zoledronate (ZOL and ZOL-PRP) every three days. After three weeks, the first lower molar was extracted. VEH-PRP and ZOL-PRP received PRP at the tooth extraction site. Euthanasia was performed at 28 days postoperatively. Clinical, histopathological, histometric and immunohistochemical analyses were carried out in histological sections from the tooth extraction site. ZOL showed lower percentage of newly formed bone tissue (NFBT), higher percentage of non-vital bone tissue (NVBT), as well as higher immunolabeling for TNFα and IL-1β. In addition, ZOL presented lower immunolabeling for PCNA, VEGF, BMP2/4, OCN and TRAP. VEH and ZOL-PRP showed improvement in the tooth extraction site wound healing and comparable percentage of NFBT, VEGF, BMP2/4 and OCN. Local application of autologous PRP proved a viable preventive therapy, which is safe and effective to restore tissue repair capacity of the tooth extraction site and prevent the occurrence of MRONJ following tooth extraction.
A new molecular thermometric sensor based on the terbium(III) complex C2mimTb(fod)4 (C2mim – 1-methyl-3-ethylimidazolium, fod− - tetrakis-6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionate), ...doped with 0.015% of its europium(III) analogue (1, C2mimTb(fod)40.99985:C2mimEu(fod)40.00015), was prepared and its thermochromic behaviour evaluated from ambient temperature up to 75 °C, including in the physiological range (35–45 °C). It was found that the intensity ratio of the 5D4→7F5 (TbIII) and 5D0→7F2 (EuIII) transitions is correlated with temperature having three different linear regimes. Visual colorimetry allowed the evaluation of the temperature in different ranges from green at ambient temperature, to yellow and finally red at higher temperatures. The TbIII complex emission intensity is extremely sensitive to small temperature variations, particularly between 25 and 35 °C, were it reaches only 40% of the initial intensity.
Confinement of the dopped TbIII tetrakis-complex in the organic polymeric matrix poly(methylmethacrylate) (PMMA) induced higher thermal stability in 1, together with a strong temperature dependence of the most intense emissive transition of the TbIII complexes. The photoluminescence quantum yield of polymer-lanthanide hybrid materials increased significantly compared with that of 1. Under 366 nm irradiation, the hybrid material presents a green colour at 25 °C that evolves to yellow at 30 °C and to a white tone at 35 °C.
•A Tb/Eu new molecular temperature sensor is presented working with very good sensitivity at physiological temperatures.•Three different linear thermometric regimes were identified for the C2mimTb(fod)40.99985.C2mimTb(fod)40.00015 complex mixture.•A semi-transparent luminescent film of PMMA was successfully prepared by incorporation of 10% of the studied Tb/Eu complex mixture.•Variation of 5 °C, from 25 to 30 °C, allows the colours of the functionalized material to change from green to yellow and then to a white tone at 35 °C.
Hydrogen peroxide (H2O2) stands as one of the foremost utilized oxidizing agents in modern times. The established method for its production involves the intricate and costly anthraquinone process. ...However, a promising alternative pathway is the electrochemical hydrogen peroxide production, accomplished through the oxygen reduction reaction via a 2-electron pathway. This method not only simplifies the production process but also upholds environmental sustainability, especially when compared to the conventional anthraquinone method. In this review paper, recent works from the literature focusing on the 2-electron oxygen reduction reaction promoted by carbon electrocatalysts are summarized. The practical applications of these materials in the treatment of effluents contaminated with different pollutants (drugs, dyes, pesticides, and herbicides) are presented. Water treatment aiming to address these issues can be achieved through advanced oxidation electrochemical processes such as electro-Fenton, solar-electro-Fenton, and photo-electro-Fenton. These processes are discussed in detail in this work and the possible radicals that degrade the pollutants in each case are highlighted. The review broadens its scope to encompass contemporary computational simulations focused on the 2-electron oxygen reduction reaction, employing different models to describe carbon-based electrocatalysts. Finally, perspectives and future challenges in the area of carbon-based electrocatalysts for H2O2 electrogeneration are discussed. This review paper presents a forward-oriented viewpoint of present innovations and pragmatic implementations, delineating forthcoming challenges and prospects of this ever-evolving field.
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•H2O2 stands as one of the foremost utilized oxidizing agents in modern times.•Promising alternative pathway is the electrochemical hydrogen peroxide production.•2-electron oxygen reduction reaction promoted by carbon electrocatalysts.•Treatment of effluents contaminated with different pollutants are presented.
In this study, we systematically investigated the electronic structure, spectroscopic (nuclear magnetic resonance, infrared, Raman, electron ionization mass spectrometry, UV-Vis, circular dichroism, ...and emission) properties, and tautomerism of halogenated favipiravir compounds (fluorine, chlorine, and bromine) from a computational perspective. Additionally, the effects of hydration on the proton transfer mechanism of the tautomeric forms of the halogenated favipiravir compounds are discussed. Our results suggest that spectroscopic properties allow for the elucidation of such tautomeric forms. As is well-known, the favipiravir compound has excellent antiviral properties and hence was recently tested for the treatment of new coronavirus (SARS-CoV-2). Through
in silico
modeling, in the current study, we evaluate the role of such tautomeric forms in order to consider the effect of drug-metabolism in the inhibition process of the main protease (M
pro
) and RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 virus. According to the molecular docking, all halogenated compounds presented a better interaction energy than the co-crystallized active ligand (−3.5 kcal mol
−1
) in the viral RdRp, in both wild-type (−6.3 to −6.5 kcal mol
−1
) and variant (−5.4 to −5.6 kcal mol
−1
) models. The variant analyzed for RdRp (Y176C) decreases the affinity of the keto form of the compounds in the active site, and prevented the ligands from interacting with RNA. These findings clearly indicated that all these compounds are promising as drug candidates for this molecular target.
In this study, we systematically investigated the electronic structure, spectroscopic properties, and tautomerism of halogenated favipiravir compounds (fluorine, chlorine, and bromine) from a computational perspective.
The Rad5 protein is an SWI/SNF family ubiquitin ligase that contains an N-terminal HIRAN domain and a RING C3HC4 motif. The HIRAN domain is critical for recognition of the stalled replication fork ...during the replication process and acts as a sensor to initiate the damaged DNA checkpoint. It is a conserved domain widely distributed in eukaryotic organisms and is present in several DNA-binding proteins from all kingdoms. Here we showed that distant species have important differences in key residues that affect affinity for ssDNA. Based on these findings, we hypothesized that different HIRAN domains might affect fork reversal and translesion synthesis through different metabolic processes. To address this question, we predicted the tertiary structure of both yeast and human HIRAN domains using molecular modeling. Structural dynamics experiments showed that the yeast HIRAN domain exhibited higher structural denaturation than its human homolog, although both domains became stable in the presence of ssDNA. Analysis of atomic contacts revealed that a greater number of interactions between the ssDNA nucleotides and the Rad5 domain are electrostatic. Taken together, these results provide new insights into the molecular mechanism of the HIRAN domain of Rad5 and may guide us to further elucidate differences in the ancient eukaryotes HIRAN sequences and their DNA affinity.
Communicated by Ramaswamy H. Sarma
Instituições públicas federais com frequência figuram como parte em conflitos judicializados (contencioso) sendo defendidas pela Advocacia-Geral da União. Na Universidade Federal de Alagoas (UFAL), ...apenas em 2021, foram ajuizadas 453 ações, as quais movimentam serviços internos de apoio ao papel de defesa da instituição e no cumprimento de decisões judiciais. Esses mesmos serviços, por sua vez, são afetados em sua qualidade por intercorrências administrativas geradoras de atrasos ou entraves ao seu funcionamento adequado, ensejando sucessivas reiterações e riscos ao ente público. O objetivo do estudo foi investigar a qualidade interna do serviço prestado pela procuradoria da UFAL nas demandas do contencioso judicial. Trata-se de um estudo qualitativo, exploratório e descritivo, baseado no modelo do Banco Interamericano de Desenvolvimento a partir das dimensões processo, relacionamento com o usuário, gestão e regulação, recursos e T.I. As mesmas dimensões orientaram os instrumentos de coleta de dados (entrevistas e questionário), com análise efetuada por meio de triangulação de fontes. Os resultados apontaram que a qualidade interna da procuradoria é influenciada principalmente pela não padronização de fluxos de trabalho, insuficiência de pessoal, carência de treinamento e incompreensão da linguagem jurídica. Concluiu-se que a mitigação desses fatores pode favorecer na redução do contencioso judicial da UFAL.
Palavras-chave: Contencioso judicial no serviço público; Dinâmica judicial nas IES; Gestão da qualidade interna.
Federal public institutions often figure as part of judicialized conflicts (litigation) being defended by the Attorney General's Office. At the Federal University of Alagoas (UFAL), in 2021 alone, 453 lawsuits were filed, which move internal services to support the institution's defense role and compliance with court decisions. These same services, in turn, are affected in their quality by administrative complications that generate delays or obstacles to their proper functioning, giving rise to successive reiterations and risks to the public entity. The objective of the study was to investigate the internal quality of the service provided by the UFAL attorney's office in the demands of judicial litigation. This is a qualitative, exploratory and descriptive study, based on the model of the Inter-American Development Bank from the dimensions process, user relationship, management and regulation, resources and IT. The same dimensions guided the data collection instruments (interviews and questionnaire), with analysis carried out through source triangulation. The results showed that the internal quality of the prosecution is mainly influenced by the non-standardization of workflows, insufficient staff, lack of training and lack of understanding of legal language. It was concluded that the mitigation of these factors can favor the reduction of UFAL's judicial litigation.
Keywords: Judicial litigation in the public service; Judicial dynamics in higher education institutions; Internal quality management.
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