Molecular Junctions for Terahertz Switches and Detectors.

Molecular electronics targets tiny devices exploiting the electronic properties of the molecular orbitals, which can be tailored and controlled by the chemical structure and configuration of the molecules. Many functional devices have been experimentally demonstrated; however, these devices were operated in the low-frequency domain (mainly dc to MHz). This represents a serious limitation for electronic applications, although molecular devices working in the THz regime have been theoretically predicted. Here, we experimentally demonstrate molecular THz switches at room temperature. The devices consist of self-assembled monolayers of molecules bearing two conjugated moieties coupled through a nonconjugated linker. These devices exhibit clear negative differential conductance behaviors (peaks in the current-voltage curves), as confirmed by ab initio simulations, which were reversibly suppressed under illumination with a 30 THz wave. We analyze how the THz switching behavior depends on the THz wave properties (power and frequency), and we benchmark that these molecular devices would outperform actual THz detectors.

An evaluation tool for backbone extraction techniques in weighted complex networks.

Networks are essential for analyzing complex systems. However, their growing size necessitates backbone extraction techniques aimed at reducing their size while retaining critical features. In practice, selecting, implementing, and evaluating the most suitable backbone extraction method may be challenging. This paper introduces netbone, a Python package designed for assessing the performance of backbone extraction techniques in weighted networks. Its comparison framework is the standout feature of netbone. Indeed, the tool incorporates state-of-the-art backbone extraction techniques. Furthermore, it provides a comprehensive suite of evaluation metrics allowing users to evaluate different backbones techniques. We illustrate the flexibility and effectiveness of netbone through the US air transportation network analysis. We compare the performance of different backbone extraction techniques using the evaluation metrics. We also show how users can integrate a new backbone extraction method into the comparison framework. netbone is publicly available as an open-source tool, ensuring its accessibility to researchers and practitioners. Promoting standardized evaluation practices contributes to the advancement of backbone extraction techniques and fosters reproducibility and comparability in research efforts. We anticipate that netbone will serve as a valuable resource for researchers and practitioners enabling them to make informed decisions when selecting backbone extraction techniques to gain insights into the structural and functional properties of complex systems.

Omicron virus emotions understanding system based on deep learning architecture.

Emotions understanding has acquired a significant interest in the last few years because it has introduced remarkable services in many aspects regarding public opinion mining and recognition in the field of marketing, seeking product reviews, reviews of movies, and healthcare issues based on sentiment understanding. This conducted research has utilized the issue of Omicron virus as a case study to implement a emotions analysis framework to explore the global attitude and sentiment toward Omicron variant as an expression of Positive feeling, Neutral, and Negative feeling. Because since December 2021. Omicron variant has gained obvious attention and wide discussions on social media platforms that revealed lots of fears and anxiety feeling, due to its rapid spreading and infection ability between humans that could exceed the Delta variant infection. Therefore, this paper proposes to develop a framework utilizes techniques of natural languages processing (NLP) in deep learning methods using neural network model of Bidirectional-Long-Short-Term-Memory (Bi-LSTM) and deep neural network (DNN) to achieve accurate results. This study utilizes textual data collected and pulled from the Twitter platform (users' tweets) for the time interval from 11-Dec.-2021 to 18-Dec.-2021. Consequently, the overall achieved accuracy for the developed model is 0.946%. The produced results from carrying out the proposed framework for sentiment understanding have recorded Negative sentiment at 42.3%, Positive sentiment at 35.8%, and Neutral sentiment at 21.9% of overall extracted tweets. The acquired accuracy using data of validation for the deployed model  is 0.946%.

Deciphering the therapeutical potentials of rosmarinic acid.

Lemon balm is herbal tea used for soothing stomach cramps, indigestion, and nausea. Rosmarinic acid (RA) is one of its chemical constituents known for its therapeutic potentials against cancer, inflammatory and neuronal diseases such as the treatment of neurofibromatosis or prevention from Alzheimer's diseases (AD). Despite efforts, recovery and purification of RA in high yields has not been entirely successful. Here, we report its aqueous extraction with optimal conditions and decipher the structure by nuclear magnetic resonance (NMR) spectroscopy. Using various physical-chemical and biological assays, we highlight its anti-aggregation inhibition potentials against the formation of Tau filaments, one of the hallmarks of AD. We then examine its anti-cancer potentials through reduction of the mitochondrial reductase activity in tumor cells and investigate its electrochemical properties by cyclic voltammetry. Our data demonstrates that RA is a prominent biologically active natural product with therapeutic potentials for drug discovery in AD, cancer therapy and inflammatory diseases.

Synthesis of lanthanide tag and experimental studies on paramagnetically induced residual dipolar couplings.

Nuclear Magnetic Resonance (NMR) spectroscopy is an indispensable technique for the structure elucidation of molecules and determination of their characteristic interactions. Residual Dipolar Coupling (RDC) is an NMR parameter that provides global orientation information of molecules but necessitates the use of an anisotropic orientation medium for the partial alignment of the target molecule with respect to the magnetic field. Importantly, anisotropic paramagnetic tags have been successful as orienting media in biomolecular NMR applications but their use in small organic molecules remains imperfect due to challenges in designing functional lanthanide complexes with varying degrees of bonding in the Ln(III) inner coordination sphere. In this study, we propose a strategy for the synthesis of the lanthanide tag 4-mercaptomethylpyridine-2,6-dicarboxylic acid, 4-MMDPA and the measurement of RDCs in a target molecule using several paramagnetic lanthanide complexes.

Recent Trends in Covalent and Metal Organic Frameworks for Biomedical Applications.

Materials science has seen a great deal of advancement and development. The discovery of new types of materials sparked the study of their properties followed by applications ranging from separation, catalysis, optoelectronics, sensing, drug delivery and biomedicine, and many other uses in different fields of science. Metal organic frameworks (MOFs) and covalent organic frameworks (COFs) are a relatively new type of materials with high surface areas and permanent porosity that show great promise for such applications. The current study aims at presenting the recent work achieved in COFs and MOFs for biomedical applications, and to examine some challenges and future directions which the field may take. The paper herein surveys their synthesis, and their use as Drug Delivery Systems (DDS), in non-drug delivery therapeutics and for biosensing and diagnostics.

Copper-Free Sonogashira Coupling for High-Surface-Area Conjugated Microporous Poly(aryleneethynylene) Networks.

A modified one-pot Sonogashira cross-coupling reaction based on a copper-free methodology has been applied for the synthesis of conjugated microporous poly(aryleneethynylene) networks (CMPs) from readily available iodoarylenes and 1,3,5-triethynylbenzene. The polymerization reactions were carried out by using equimolar amounts of halogen and terminal alkyne moieties with extremely small loadings of palladium catalyst as low as 0.65 mol %. For the first time, CMPs with rigorously controlled structures were obtained without any indications of side reactions, as proven by FTIR and solid-state NMR spectroscopy, while showing Brunauer-Emmett-Teller (BET) surface areas higher than any poly(aryleneethynylene) network reported before, reaching up to 2552 m(2) g(-1) .

Efficiency and Flexibility of Fingerprint Scheme Using Partial Encryption and Discrete Wavelet Transform to Verify User in Cloud Computing.

Now, the security of digital images is considered more and more essential and fingerprint plays the main role in the world of image. Furthermore, fingerprint recognition is a scheme of biometric verification that applies pattern recognition techniques depending on image of fingerprint individually. In the cloud environment, an adversary has the ability to intercept information and must be secured from eavesdroppers. Unluckily, encryption and decryption functions are slow and they are often hard. Fingerprint techniques required extra hardware and software; it is masqueraded by artificial gummy fingers (spoof attacks). Additionally, when a large number of users are being verified at the same time, the mechanism will become slow. In this paper, we employed each of the partial encryptions of user's fingerprint and discrete wavelet transform to obtain a new scheme of fingerprint verification. Moreover, our proposed scheme can overcome those problems; it does not require cost, reduces the computational supplies for huge volumes of fingerprint images, and resists well-known attacks. In addition, experimental results illustrate that our proposed scheme has a good performance of user's fingerprint verification.

Avaliação do comprimento do colo uterino em gestantes normais entre 20 e 34 semanas de gestação por meio da ultrassonografia endovaginal / Endovaginal sonographic assessment of cervical length in healthy pregnant women between 20 and 34 gestational weeks

OBJETIVO: Avaliar o comprimento do colo uterino pela ultrassonografia transvaginal em uma população de gestantes normais e construir uma curva de normalidade no período de 20 a 34 semanas de gestação. MATERIAIS E MÉTODOS: Estudo de corte transversal, incluindo 145 gestantes normais, com feto único, vivo, sem enfermidades, entre 20 e 34 semanas de gravidez, examinadas nos serviços de ultrassonografia do Hospital Universitário Júlio Müller e de uma clínica privada. As gestantes foram submetidas a ultrassonografia endovaginal, com registro do comprimento cervical. Critérios de exclusão foram: parto prematuro, rotura prematura pré-termo das membranas, placenta prévia, uso de fármacos tocolíticos e/ou progesterona, cerclagem ou qualquer intervenção cirúrgica prévia no colo. A associação entre o comprimento do colo uterino e a idade gestacional foi examinada por regressão linear. RESULTADOS: O comprimento cervical diminuiu progressivamente em 0,8 mm a cada semana, à medida que a idade gestacional progrediu (r = -0,351; p < 0,001). As mulheres que tiveram afunilamento cervical apresentaram colo mais curto que as demais (p = 0,001). A interpolação dos percentis 5, 50 e 95 provê gráfico passível de ser utilizado como referência. CONCLUSÃO: O comprimento médio cervical em gestantes normais diminui 0,8 mm por semana, entre a 20ª e a 34ª semanas de gestação.

OBJECTIVE: To evaluate the cervical length by means of transvaginal ultrasonography in a population of healthy pregnant women, developing a normality curve in the period between the 20th and 34th gestational weeks. MATERIALS AND METHODS: Cross sectional study involving 145 healthy singleton pregnancies with healthy fetuses between 20 and 34 weeks of gestation, evaluated at the units of ultrasonography of Hospital Universitário Júlio Müller and of a private center. Each pregnant woman underwent a single transvaginal ultrasonography study, with measurement and recording of the cervical length. Exclusion criteria were: preterm labor, preterm premature rupture of membranes, placenta previa, use of tocolytics and/or progesterone, cerclage or any surgical intervention prior to pregnancy. The association between cervical length and gestational age was evaluated by linear regression analysis. RESULTS: The cervical length presented a progressive decrease (0.8 mm/week) as the gestational age progressed (r = -0.351; p < 0.001). The women with cervical funneling presented shorter cervix (p = 0.001). Interpolation of the 5th, 50th and 95th percentiles provides a graph to be used as a reference. CONCLUSION: The mean cervical length decreases about 0.8 mm per week in the period between the 20th and 34th gestational weeks.

Synthesis and Chain-Length Dependence of the Electronic Properties of π-Conjugated Dithieno[3,2-b:2',3'-d]pyrrole (DTP) Oligomers.

N-(2-ethylhexyl)dithieno[3,2-b:2',3'-d]pyrrole has been prepared and its dimer and trimer have been synthesized by Stille coupling. The electrochemical and optical properties of these compounds have been investigated by cyclic voltammetry, UV-Vis, and fluorescence emission spectroscopies. The obtained results show that these strongly luminescent compounds can be oxidized into stable cation radical and dication state. The analysis of the chain length dependence of the electronic properties indicates that the predicted bandgap of an ideal polymer chain should be considerably smaller than the experimental results reported until now. This difference is discussed in terms of reactivity of the dithieno[3,2-b:2',3'-d]pyrrole (DTP) unit.

Isolamento e identificaçäo de bactérias anaeróbicas e Gardnerella vaginalis, antes e após a eletrocauterizaçäo do colo uterino / Isolation and identification of anaerobic bacteria and Gardnerella vaginalis vefore and after uterine cervix electric-coagulation

As bactérias anaeróbias constituem importante componente da flora bacteriana normal do colo uterino e, em determinadas condiçöes, podem assumir um caráter patogênico. A eletrocauterizaçäo do colo uterino, por sua vez, por alterar as condiçöes microbiológicas neste sítio, pode propiciar o aparecimento de infecçöes subclínicas, retardando o processo de cicatrizaçäo. O objetivo do presente trabalho foi isolar e identificar bactérias anaeróbias e Gardnerella vaginalis antes e após a eletrocauterizaçäo do colo uterino, analisando o efeito desta medida sobre esta flora. Foram estudadas 32 pacientes submetidas à eletrocauterizaçäo cervical, realizando-se colheitas de espécimes clínicos antes e no 7§ dia após o procedimento. Observou-se que a eletrocauterizaçäo do colo uterino levou a um aumento na incidência de Gardnerella vaginalis e de bactérias anaeróbias, microaerófilas e facultativas, tanto na regiäo cervical quanto na regiäo vaginal