bluuebunny/crossref_metadata_2025 huggingface dataset:
Priama aplikácia „gilotínového ustanovenia“ článku 17 Európskeho dohovoru o ochrane ľudských práv a základných slobôd pri nenávistných prejavoch a jej úskalia
Authors: Šajmovič Peter
Published: July 2022

V článku 17 Európskeho dohovoru o ochrane ľudských práv a základných slobôd (ďalej len „Dohovor“) je za účelom obrany demokracie a jej hodnôt zakotvená tzv. „klauzulu zákazu zneužitia práv“. Štrasburské orgány ochrany práva (t. j. Európsky súd pre ľudské práva a bývalá Európska Komisia pre ľudské práva pôsobiaca až do jej zániku v roku 1998) v niektorých prípadoch týkajúcich sa najzávažnejších foriem nenávistných prejavov pristupujú k tzv. priamej aplikácii čl. 17 Dohovoru čo má za následok, že stažnosť na porušenie slobody prejavu zaručenej v čl. 10 ods. 1 Dohovoru je v takomto prípade priamej aplikácie čl. 17 Dohovoru odmietnutá ako ratione materiae nezlúčiteľná s ustanoveniami Dohovoru bez toho, že by došlo ku konaniu o podstate sťažnosti (t. j. o merite veci). Práve v dôsledku priamej aplikácie čl. 17 Dohovoru v niektorých prípadoch týkajúcich sa najzávažnejších foriem nenávistných prejavov sa toto ustanovenie niekedy zvykne označovať aj ako tzv. „gilotónové ustanovenie“. Cieľom tohto príspevku je tak na základe analýzy kľúčových faktorov týkajúcich sa priamej aplikácie čl. 17 Dohovoru, ktorými sú predovšetkým charakteristika konania spadajúceho do rozsahu čl. 17 Dohovoru, podstata priamej aplikácie čl. 17 Dohovoru („gilotínový efekt“) a problematické aspekty (úskalia) priamej aplikácie čl. 17 Dohovoru pokúsiť sa posúdiť, či priamu aplikáciu čl. 17 Dohovoru možno v súčasnej demokratickej Európe považovať za vhodnú metódou boja proti najzávažnejším formám nenávistných prejavov.
El Teatro Principal de Valencia durante la temporada teatral 1876-1877
Authors: Torner Feltrer Fernando
Published: July 2022

El presente artículo revisa toda la actuación operística que hubo en Valencia durante la temporada de 1876 a 1877, la segunda que coincide con la
restauración de la monarquía de Alfonso XII. A través de la actividad que se produjo en el Teatro Principal de Valencia, examinamos toda la labor operística que hubo en esta ciudad, aunque esta temporada no fue el único lugar donde se representó ópera en Valencia, ya que también hubo actividad en el Teatro Apolo, de la cual también damos cuenta en este artículo. Una temporada marcada por el gran número de enfermedades que sufrió la compañía del empresario Ríos. Asimismo, es también reseñable la importante presencia del tenor Roberto Stagno, uno de los cantantes más sobresalientes en aquel momento en los teatros europeos.
Morir sin triunfar. La fabricación del mito romántico del compositor Gomis en 1836
Authors: Múrcia i Cambra Miquel À.
Published: July 2022

El estudio biográfico y musicológico sobre el compositor romántico Melchor Gomis sigue inacabado. En las siguientes páginas tratamos de sumergirnos en los relatos variantes y alternativos que se ofrecieron después de la muerte del músico hispánico, en 1836. En esta línea, se cuestiona la teoría comúnmente aceptada sobre la no pervivencia de su memoria: Gomis siguió presente en los artículos especializados y las ediciones musicales después de su muerte. Además, nuestro estudio se centra en la observación de la fijación de sobresignificados y la adquisición de valores sobre su anhelo biográfico. Con la identificación de las ficciones y de la huella de Gomis en los discursos posteriores a su muerte, podemos obtener una visión más completa del proyecto de vida del compositor.
Wire perforation of the missed tiny aneurysm originating from the fenestrated A1 segment during the endovascular approach
Authors: Shin Seung Ho , Cho Won Ho , Cha Seung Heon , Ko Jun Kyeung
Published: July 2022

Vascular anomaly and aneurysmal formation of an anterior communicating artery (ACOM) complex has often been reported. Because of such a complicated relationship between the vascular structure and aneurysms, ACOM aneurysm is one of the most difficult aneurysms to treat among other common anterior circulation aneurysms. We herein report a case of wire perforation of a missed tiny aneurysm arising from the fenestrated A1 segment during the endovascular approach to ACOM aneurysm. Although the fenestration of A1 segment is a rare vascular anomaly, it is likely to accompany saccular type aneurysms in the vicinity of the vascular anomaly. Endovascular treatment for ACOM aneurysm requires more detailed evaluations of the accompanying vascular anomaly and hemodynamics around ACOM to avoid complications.
A Ge-based dual channel rectified single ended Schottky barrier field effect transistor for 2.45 GHz microwave wireless energy transmission
Authors: Bi Si-Han , Song Jian-Jun , Zhang Dong , Zhang Shi-Qi ,   Key Laboratory of Wide Bandgap Semiconductors, School of Microelectronics, Xidian University, Xi’an 710071, China,   Radiation-resistant Integrated Circuit Technology Laboratory, China Aerospace Science and Technology Corporation, Xi’an 710071, China
Published: July 2022

Rectifier component is a core part of a microwave wireless energy transmission system, and the development of new rectifier components is an important research direction in this field. Schottky diodes and field-effect transistors are currently the mainstream rectifier devices, but they have a limited rectification range and cannot achieve a wide-range rectification of both weak energy and medium energy density at the same time. In view of this, in this work proposed and designed is a Ge based p-type single-ended Schottky barrier field effect transistor (Schottky contact at the source and standard p+ doping at the drain) for 2.45 GHz microwave wireless energy transmission. Based on this, the Schottky structure of the device is fully utilised and a new diode connection is used in order to realize a dual channel wide range rectification of the trench and source lined Schottky structure opened at different bias voltages. Simulations are carried out by using the Silvaco TCAD software. For a half-wave rectifier circuit with a load of 0.3 pF and 70 kΩ, a wide range from –20 to 24 dBm rectification is achieved, which is 8 dBm wider than the range of Ge field-effect transistors under the same conditions, and the overall rectification efficiency is higher in the range, with a peak rectification efficiency of 57.27% at 16 dBm. The rectification efficiency at –10 dBm weak energy density reaches 6.17%, which is more than 7 times that of Ge FETs under the same conditions.
Short physical performance battery as a predictor of mortality in community-dwelling older adults: a longitudinal study in the Brazilian Amazon region
Authors: Silva Caroline de Fátima Ribeiro , Gonçalves Ohara Daniela , Pena Matos Areolino , Nunes Pinto Ana Carolina Pereira , Sousa Pegorari Maycon
Published: July 2022

Background

The Short Physical Performance Battery (SPPB) is an instrument for assessing physical performance widely used in research among the elderly in multiple settings. We did not find Brazilian longitudinal studies that aimed to analyze the predictive capacity and accuracy of the SPPB among community-dwelling older adults and no systematic reviews were found on the accuracy of the SPPB in predicting mortality in community- dwelling older adults. This study aimed to analyze the capacity and accuracy of the SPPB for predicting mortality in community-dwelling older adults, as well as to determine cut-off points for men and women.

Method

Longitudinal observational study conducted with 411 (70.1 ± 7.25 years) community-dwelling older adults, between 2017 and 2020 (37.7 ± 6.24 months). Physical performance was evaluated using the SPPB and information on the all-cause mortality rate was also recorded. Multivariate Cox regression analyses and curves were performed using the Kaplan–Meier method. Receiver Operating Characteristic (ROC) curves were constructed, with the parameters of area under the ROC curve (AUC) to determine cutoff points for discriminating mortality, considering a significance level of 5% (p < 0.05) and 95% confidence interval (CI) 95%.

Results

Older adults with very low and low physical performance in the SPPB, showed higher risks of mortality (HR = 9.67; 95% CI [1.20–77.65]; HR = 4.06; 95% CI [1.09–15.01]), respectively. In the subtest’s analysis, older adults with low performance in the balance (HR = 0.54; 95% CI [0.36–0.81]) and gait speed tests (HR = 0.50; 95% CI [0.33–0.76]) showed greater risks of dying. The same was reproduced for categories in each test (participants that scored 2 points in the balance test had an HR = 5.86; 95% CI [1.84–18.61] and 2 points in the gait speed test, HR = 5.07; 95% CI [1.76–14.58]. The cutoff point ≤ 9 in the SPPB set the discriminator criterion for mortality in older people of both sexes.

Conclusions

The SPPB, as well as the balance and gait speed subtests were predictors of mortality, and the SPPB is accurate in predicting mortality among community-dwelling older adults.
CD14 and CD26 from serum exosomes are associated with type 2 diabetes, exosomal Cystatin C and CD14 are associated with metabolic syndrome and atherogenic index of plasma
Authors: Pérez-Macedonio Claudia Paola , Flores-Alfaro Eugenia , Alarcón-Romero Luz del C. , Vences-Velázquez Amalia , Castro-Alarcón Natividad , Martínez-Martínez Eduardo , Ramirez Monica
Published: July 2022

Background

Exosomes are microvesicles that actively participate in signaling mechanisms and depending on their content can contribute to the development of different pathologies, such as diabetes and cardiovascular disease.

Objective

The aim of this study was to evaluate the association of cystatin C, CD26, and CD14 proteins in serum exosomes from patients with Type 2 Diabetes (T2D), metabolic syndrome (MetS), and atherogenic index of plasma (AIP).

Methods

Serum exosomes were isolated by ultracentrifugation from 147 individuals with and without diabetes. Both anthropometric and metabolic parameters were registered from everyone. The levels of exosomal proteins cystatin C, CD26, and CD14 were quantified by ELISA. The association between protein levels and T2D or atherogenic risk factors was analyzed by linear regression and generalized regression models.

Results

We observed a significant correlation of increased glucose with elevated levels of Cystatin C, and an effect of T2D on the levels of CD26 (β = 45.8 pg/µg; p = 0.001) and CD14 (β = 168 pg/µg; p < 0.001) compared to subjects without T2D. CD14 was significantly related to T2D, metabolic syndrome, glucose, and the Atherogenic Index of Plasma (AIP). Additionally, we observed a significant effect of metabolic syndrome MetS on the increase of exosomal Cystatin C and CD14.

Conclusions

T2D may contribute to the increase of CD14 protein contained in exosomes, as well as to the predisposition of atherogenic events development due to its relationship with the increase in serum triglyceride concentrations and the AIP score. Finally, the increased levels of CD14 and Cystatin C in exosomes are related to MetS. The analysis of exosome contents of diabetic patients remains an incipient field, so extensive characterization is crucial for their use as biomarkers or to analyze their possible contribution to diabetic complications.
Cyclocytidine hydrochloride inhibits the synthesis of relaxed circular DNA of hepatitis B virus
Authors: Wang Xue , Xiao Yihan , Cui Zhigang , Li Zongxin , Li Lihua , Wu Lixian , Yin Feifei , Cui Xiuji
Published: July 2022

Background

Cyclocytidine hydrochloride (HCl) has been reported to inhibit DNA synthesis by affecting DNA polymerase. Here, we tested the antiviral effect of cyclocytidine on hepatitis B virus (HBV) DNA synthesis, which is reliant on DNA polymerase activity.

Materials and Methods

Cyclocytidine HCl was treated to HBV-producing HepAD38 cells or added to an endogenous polymerase reaction, and HBV DNA was detected by Southern blot.

Results

Treatment of 20 µM cyclocytidine HCl significantly decreased the production of relaxed circular (rc) DNA in HepAD38 cells and block rcDNA synthesis in endogenous polymerase reaction (EPR), a cell free assay, possibly by inhibiting the HBV DNA polymerase activity.

Conclusion

Cyclocytidine HCl could inhibit the synthesis of HBV rcDNA, the precursor of covalently closed circular DNA, and this result provides a case for the usage of “old” drugs for “new” applications.
Evaluation of Low-dose and High-dose Intravaginal Misoprostol for Induction of Labour: A Randomised, Double-blinded, Single Centre Study
Authors: Mummalaneni Gowthami , Sravanthi Thodeti Chaitanya , Sridhar I , Sayana Suresh Babu , Kumar Meela Ranjith
Published: July 2022

Introduction: Misoprostol is a synthetic prostaglandin E1 analogue widely used for cervical ripening and labour induction. However, misoprostol optimal dose required to induce labour is still controversial. Aim: To determine the efficacy and safety of 25 µg and 50 µg of intravaginal misoprostol for induction of labour at term and to evaluate maternal and neonatal complications. Materials and Methods: The present study was a prospective, randomised, double blind, single centre study carried out during March 2019 to December 2020. All the selected participants were randomised (1:1) to group 1 which received 25 µg of intravaginal misoprostol (n=70) and group 2 received 50 µg of intravaginal misoprostol (n=70). Based on the Bishop’s score, misoprostol was chosen as labour inducing agent. Number of misoprostol doses, mode of delivery, vaginal delivery duration, maternal and neonatal complications was recorded. Statistical significance among study groups were analyzed by using Chi-square test. Results: Postdatism was most frequently reported indication in both the study groups (57.1% and 52.9%). A total of 14 and 4 participants in group 2 and group 1 received only single dose of misoprostol (p<0.01). Participants who received misoprostol 50 µg (n=60, 85.7%) has slightly showed higher vaginal deliveries compared to misoprostol 25 µg (n=57, 81.4%). The mean duration of induction time in group 2 was 10.12 hours and group 1 women showed 13.56 hours (p<0.0001). Maternal and neonatal complications were slightly higher in 50 µg misoprostol group. Maternal complications such as uterine tachysystole (n=4), Postpartum Haemorrhage (PPH) (n=3) and uterine hyperstimulation syndrome (n=2). Neonatal complications with 50 µg misoprostol were Apgar <7 at 1 min (n=4), Apgar <7 at 5 min (n=3), Special Care Baby Unit (SCBU) admissions (n=2) and severe birth asphyxia (n=1). Misoprostol with 25 µg has showed Apgar <7 at 1 min (n=2), Apgar <7 at 5 min (n=2), SCBU admissions (n=1). Conclusion: The efficacy and safety results of 25 µg intravaginal misoprostol were comparable with 50 µg of intravaginal misoprostol for labour induction. The advantages of 50 µg misoprostol were it favours the vaginal deliveries, lesser active induction time and decrease number of misoprostol doses required to induce labour. However, higher dose of misoprostol showed higher frequencies of both maternal and neonatal complications.
Application of Artificial Neural Network in Rectification
Authors: An Teng , Xu Jumei
Published: July 2022

Distillation is a unit operation process that uses the different volatility of various components in the mixture to separate or purify. The key problem has always been how to improve the separation effect of rectification. However, there are complex coordination, constraints and conflicts between the objective function and the input parameters of the rectification system, and it is difficult to obtain the optimal operating conditions by applying traditional control methods. With its powerful computing power and adaptive learning ability, the artificial neural network can establish the nonlinear correspondence between the objective function and multiple independent variables without relying on the mathematical model, which provides a powerful tool for the optimal operation and design of the distillation column. This article will introduce the basic principles, typical network models and development history of artificial neural networks, and summarize the application and research progress of artificial neural networks in distillation.
Global Dynamics of Fractional-order Model for Malaria Disease Transmission
Authors: Helikumi Mlyashimbi , Lolika Paride O.
Published: July 2022

In this study, we formulated and analyzed a fractional-order model for malaria disease transmission using Atangana-Beleanu-Caputo in sense to study the effects of heterogeneity vector biting exposure on the human population. To capture effects the heterogeneity vector biting exposure, we sub-divided the human population into two sub-groups namely; the population in high and low risk areas. In the model analysis, we computed the basic reproduction number R0 and qualitatively used to assess the existence and extinction of disease in the population. Additionally, we used the fixed point theorem to prove the existence and uniqueness of solutions.Numerical schemes for both Euler and Adam-Bathforth-Moulton are present in details and used in model simulations. Furthermore, we performed the numerical simulation to support the analytical results in this study. From numerical simulations, we estimated the values of model parameters using least square fitting method for the real data of malaria reported in Zimbabwe. The sensitivity analysis of the model parameters was done to determine the correlation between model parameters and R0: Finally, we used the Euler and Adam-Bashforth-Moulton scheme to simulate the model system using estimated parameters. Overall, we noted that fractional-order derivatives have more in uence on the dynamics of malaria disease in the population.
Development of Operating Model for the Design of Stirrer Arms of Slurries: Design and Fabrication of Stirrer Arms
Authors: Okpighe Sunday Okerekehe , Shadrack M. U. , Nwosu H. U.
Published: July 2022

The “Development of Operating Model for the Design of Stirrer Arms of Slurries: Design and Fabrication of Stirrer Arms” is reported. In the previous research titled “Development of Operating Model for the Design of Stirrer Arms of Slurries: A Review”, a research gap was identified to exist between the Two Z and TETE blade stirrer arms. The aim of this current research was to demonstrate a model/design and fabrication of the Two Z and TETE blade stirrer arms with the view of creating a platform for the future comparative tests of these stirrer arms. The specific objectives for this research include the identification and selection of all the materials needed to achieve the aim of the research (including the selection of the mixer that will host the stirrer arms); Design of the Two Z and TETE blades of the stirrer arms (with the application of the Solid Work software) in tandem with the selected mixer; Design calculations for the Two Z and TETE blades; Fabrication of the Two Z and TETE blades of stirrer arms in tandem with the selected mixer; Constitution of the slurry to be mixed and Calibration of the slurry viscosity. All the set objectives for this research were achieved and consequent on the foregoing, the theoretical (predicted or expected) mixing power consumption for the Two Z, TETE and hybrid Two Z – TETE blade stirrer arms were determined. The order of merit analysis for the theoretical (predicted or expected) power revealed the Two Z stirrer arm as the most efficient. Further future work should include empirical performance tests of the Two Z, TETE and hybrid Two Z – TETE stirrer arms. This will establish/validate the level of degree of agreement between the theoretical (expected) and empirical (observed) mixing power consumption of the stirrer arms. Also such tests will highlight the comparative mixing power and energy efficiency of these stirrer arms hence the order of merit of being called to bar.
Recent Development of Biomass and Plastic Co-Pyrolysis for Syngas Production
Authors: Mensah Isaac , Ahiekpor Julius C. , Bensah Edem C. , Narra Satyanarayana , Amponsem Bright , Antwi Edward
Published: July 2022

Co-pyrolysis is an enhanced thermochemical conversion process employed to convert lignocellulosic and plastic materials into more improved liquid, gaseous, and solid biofuels. Co-pyrolysis has been used extensively for the manufacturing of liquid biofuels (bio-oil) with little emphasis on syngas production. However, syngas is a promising source of renewable power generation and green chemicals. Production of syngas provides an opportunity for achieving negative carbon dioxide through the implementation of carbon capture and storage. This paper reviews the production of syngas through co-pyrolysis of plastic and biomass wastes in a typical municipal solid waste from Ghana. The effects of key production parameters including type of feedstock, temperature, catalysts, heating rate, reactor configuration, and residence time on the yield and composition of the syngas are outlined. The paper attempts to unravel the kinetic mechanisms of the co-pyrolysis process and the synergistic effects that co-exist between the feedstocks during syngas production. It was found that syngas can be optimized in terms of yield and quality to be used as transportation fuels, chemicals, and the production of electricity through the co-pyrolysis process.
On the Fast Evaluation of Polynomials
Authors: Fuentes P. Abascal , Tirado F. Fueyo , Quintas D. Garcia , Meana J. Jimenez , Muniz A. Palacio
Published: July 2022

Minimizing the computational cost of polynomial evaluation is a main problem in Computational Science. Horner's algorithm efficiently solves the problem of evaluating a polynomial of degree n in time O(n). It is also used to evaluate multivariate polynomials and, as an extension, matrix polynomials.If, in addition, a parallel execution of this method can be carried out, the computational cost of this problem would be further minimized.This makes it especially important to develop a strategy for parallel execution of Horner's method for fast and ecient polynomial evaluation.In this paper we present a parallelization of Horner's method based on polynomial partitioning, as well as a modification of this method to exploit its advantages in the evaluation of sparse polynomials.We also provide an analysis of the numerical error between the proposed parallel method and the classic algorithm.
Knowledge, Awareness, & Attitude towards Implant Therapy for Replacing Missing Teeth: A Cross Sectional Survey from Northern West Bengal, India
Authors: Akram Washim , Sinha Arindam , Pal Moumita , Nagaraj E. , Kondody Rony T.
Published: July 2022

Aims: The purpose is to assess the awareness, knowledge & attitude towards implant therapy for replacing missing teeth.

Material & Methods: This cross-sectional study was conducted in Department of Dentistry of Malda Medical College & Hospital, Malda, West Bengal, over a period of July 2019 to July 2021. A total of 1200 partial or complete edentulous patient, age above 15 years were selected. A standardized 9 close ended questions were asked to patients. The data were collected in tabular form and statistically analyzed by Chi-Square test.

Results: We found that 22.83% (274) were aware about dental implant therapy, among them male were 13%(156) and female were 9.83%(118). The difference between male and female awareness were statistically highly significant (p<.001). The major source of information regarding implant was dentist (55.83%). Only 8.08% (97) were interested in implant therapy in near future, among them 5.08%(61) male and 3%(36) were female. The difference were statistically non significant (p=0.62). Major reason for not opting implant therapy was high cost (32.76%).

Conclusion: Within limitation of the study we concluded very less awareness (22.83%) regarding implant therapy among the Malda Population. So there is need for bringing more awareness program brought by various Government & Public organization to educate the general population
Independência, conflito pós-colonial e competição Leste-Oeste em Angola, 1975-1976
Authors: Domínguez Avila Carlos Federico
Published: July 2022

Este texto examina o posicionamento dos atores, as consequências e as ramificações da Independência angolana e acontecimentos conexos sob a perspectiva da evolução do sistema internacional. Trata-se de um artigo de pesquisa fundamentado em documentação diplomática brasileira recentemente desclassificada. O artigo constata a complexa correlação de atores e de agendas, especialmente no que diz respeito ao nacionalismo pan-africano, à competição Leste-Oeste, às ambições hegemônicas de potências regionais e à relevância dos atores não-estatais. O conflito angolano do período 1975-1976 erigiu-se num evento de interesse global.
“Eu tenho uma responsabilidade”
Authors: Sá Schat Ana Luíza , Câmara Antônio da Silva
Published: July 2022

Este artigo propõe-se a analisar as representações de mulheres na obra Nossa Irmã Mais Nova (2015), do cineasta Koreeda Hirokazu. Através da análise fílmica e da revisão bibliográfica, objetiva-se caracterizar o cinema de Koreeda, além de investigar e comparar as diferentes personagens do filme escolhido, buscando identificar de que modo a mudança na organização familiar e a diferença geracional impactam a posição de cada uma. Entendendo tais representações enquanto elementos simbólicos, historicamente situados, busca-se contextualizar o filme e o diretor, explorando os aspectos culturais da sociedade japonesa. Para tanto, o trabalho apresenta quatro momentos: primeiro, uma discussão sobre cinema e representação; segundo, uma exposição acerca da questão da mulher no Japão moderno; a seguir, um informe biográfico sobre o diretor; e, finalmente, a análise da obra por meio da decupagem e da revisão bibliográfica.
Palavras-chave: Koreeda Hirokazu; mulheres; representação.
nova história dos iorubás
Authors: Mann Kristin
Published: July 2022

Resenha de:

OGUNDIRAN, Akinwumi. The Yorùbá: A New History. Bloomington, Indiana: Indiana University Press, 2020. 532 p.
Fotografia no Mali (desde 1930)
Authors: Moreau Daniela
Published: July 2022

Resenha de:

KELLER, Candace. Imaging Culture: Photography in Mali, West Africa. Indiana: Indiana University Press, 2021. 453 p.
Horizontes futuros em uma revolta escrava no sul do Brasil
Authors: Mügge Miquéias H.
Published: July 2022

Resenha de:

PEDROSO, Wagner de Azevedo. Nazário e um plano de rebelião escrava na Aldeia dos Anjos: “os brancos eram uns pelos outros, por isso os negros também deviam fazer o mesmo”. Porto Alegre: Editora Coragem, 2020. 167 p.
Hubert Harrison
Authors: Pericás Luiz Bernardo
Published: July 2022

Resenha de:

PERRY, Jeffrey B. Hubert Harrison: The Struggle for Equality, 1918–1927. Nova York: Columbia University Press, 2021. 998 p.
Quando Zumbi chegar, o que vai acontecer?
Authors: Mercês Calila das
Published: July 2022

Resenha de:

CARDOSO, Edson Lopes. Intimações do desumano. Salvador: Quarteto, 2021. 74 p.
Produção Científica Versus Produção Tecnológica: a trajetória do Instituto Federal de Educação, Ciência e Tecnologia da Bahia (IFBA)
Authors: Souza Jaqueline , Souza André Luis Rocha , Nano Rita Maria Weste , Silva Marcelo Santana , Araújo Marcio Luis Valença , Miranda Morjane Armstrong Santos de
Published: July 2022

A criação dos Institutos Federais (IFs) em 2008 foi um marco no campo da política pública de educação profissional em todos os níveis e modalidades, com reflexos, também, no desenvolvimento local e regional. Entre os objetivos dos IFs, está o de realizar pesquisas aplicadas, estimulando o desenvolvimento de soluções técnicas e tecnológica para atender às demandas sociais. Esta pesquisa exploratória, de natureza bibliográfica e documental, buscou analisar a trajetória da produção científica e tecnológica no âmbito do IFBA. Os dados foram extraídos: da Web of Science, Plataforma Stela Experta e do DINOV/IFBA. Os resultados demonstram que a produção científica ainda é muito superior à tecnológica e que, mesmo havendo um aumento desses indicadores ao longo do tempo, a quantidade de transferência de tecnologia ainda é bastante incipiente ou ausente.
Injection‐Molded Ultrahigh Molecular Weight Polyethylene Material with Improved Moldability for Artificial Joint Implants Design
Authors: Ayad Omar G. , Mourad Abdel-Hamid I. , Greish Yaser E. , Karam Sherif M. , Alnaqbi Ali Hilal
Published: July 2022

Fabrication of pure ultrahigh molecular weight polyethylene (UHMWPE)‐based artificial joint implants is a bottleneck problem as it is only limited to quasistatic approaches that have low efficiency due to the high density of fusion defects. The main objective of this work is to improve the moldability of UHMWPE using the injection molding technique while maintaining its superior mechanical integrity. Groups of UHMWPE samples are injected at barrel melting temperatures of 300, 320, 340, and 360 °C, at various injecting pressures. The high‐temperature melting (HTM) allows the fabrication of robust UHMWPE samples using injection molding with an improved yield stress of 29.63 ± 3.19, compared to 23.0 ± 0.6 and 17.8 ± 0.75 achieved by HTM compression molding and conventional compression molding, respectively. Moreover, the scanning electron microscopy (SEM) results suggest an almost complete elimination of all fusion defects, and that is supported by the outstanding tensile strain at breaks reaching up to approximately 1300%. The thermochemical properties of the injection‐molded UHMWPE samples are tested as well to investigate the impact of HTM on their characteristics. Moreover, the materials’ biocompatibility and wear are assessed. This study sets up a new approach to fabricate high‐performance injection‐molded UHMWPE joint implants by HTM.
Photon‐Pen Writing for Metal Oxide‐Based Versatile Nanosensors
Authors: Bae Garam , Kim Minji , Jang Moonjeong , Kwon Yeong Min , Yim Soonmin , Song Wooseok , Myung Sung , Lee Sun Sook , Hasan Tawfique , An Ki‐Seok
Published: July 2022

Low‐temperature processes and simplification of lithographic techniques are key challenges for the fabrication of solution‐processed metal oxide‐based nanodevices. Recent breakthroughs in location‐specific synthetic methodologies involving inkjet printing and photon‐activation routes have enabled lithography‐free and bottom‐up fabrication of such devices. However, a revolutionary strategy to resolve room‐temperature direct fabrication of metal oxide‐based materials still remains elusive. Here, a pertinent route enabling wafer‐scale, location‐specific direct‐writing, termed “photon‐pen writing (PPW),” of functional metal oxide‐based devices is proposed. Using PPW, fabrication of elaborate patterns of metal oxides is demonstrated through location‐specific dechlorination and subsequent oxidation via thermal energy transfer of a focused infrared laser in ambient environment. By tailoring process parameters, precise manipulation of the chemical and structural features of the PPW‐produced metal‐oxide patterns are demonstrated. The versatility of the PPW process by realizing a highly sensitive, stable, uniform, and wafer‐scale nanosensor array for gas and light detection using PPW‐ZnO channel and PPW‐ITO electrodes is demonstrated, with 4.1% of response at 50 ppb NO2 and 2.93 ± 0.23 µA of photocurrent for 0.76 mW cm−2, 254 nm UV light. A new route toward wafer‐scale production of bespoke nanosensor arrays onto single chip for next‐generation nanoelectronics is introduced.
Durability Improvement of Breeze‐Driven Triboelectric‐Electromagnetic Hybrid Nanogenerator by a Travel‐Controlled Approach
Authors: Luo Yingjin , Chen Pengfei , Cao Leo N. Y. , Xu Zijie , Wu Ying , He Gaofa , Jiang Tao , Wang Zhong Lin
Published: July 2022

Triboelectric nanogenerator (TENG), as an emerging technology for distributed energy harvesting, provides a promising energy solution for self‐powered environmental monitoring. However, the abrasion of triboelectric materials lowers the output performance of TENGs, severely limiting their practical applications. Herein, a novel travel‐controlled approach, by combining a gear train and cam switch, is proposed to reduce the mechanical wear. The automatic switching between the contact and non‐contact modes can be achieved in a tunable frequency, showing excellent electrical stability by maintaining 90% of electric outputs after continuous operation for 80 h (1 920 000 cycles). Meanwhile, based on the structural optimization, the power density per unit wind speed of the travel‐controlled TENG (TC‐TENG) is doubled as compared with that of previous related works. Moreover, by integrating the triboelectric‐electromagnetic hybrid device with an energy management circuit, a self‐powered close‐looped environmental monitoring and alarming system are demonstrated. Under breezy conditions (below 3 m s−1), the system can detect the environmental information continuously and steadily, and transmit it wirelessly to a mobile device. This work renders a novel approach to reducing the wear in TENGs toward self‐powered wireless sensing systems, showing broad application prospects in distributed unmanned environmental monitoring, smart farming, and Internet of Things.
Emergent Magnetic Fan Structures in Manganite Homojunction Arrays
Authors: Guasco Laura , Khaydukov Yury , Kim Gideok , Keller Thomas , Vorobiev Alexei , Devishvili Anton , Wochner Peter , Christiani Georg , Logvenov Gennady , Keimer Bernhard
Published: July 2022

Devices with tunable magnetic noncollinearity are important components of superconducting electronics and spintronics, but they typically require epitaxial integration of several complex materials. The spin‐polarized neutron reflectometry measurements on La1−xSrxMnO3 homojunction arrays with modulated Sr concentration reported herein have led to the discovery of magnetic fan structures with highly noncollinear alignment of Mn spins and an emergent periodicity twice as large as the array's unit cell. The neutron data show that these magnetic superstructures can be fully long‐range ordered, despite the gradual modulation of the doping level created by charge transfer and chemical intermixing. The degree of noncollinearity can be effectively adjusted by low magnetic fields. Notwithstanding their chemical and structural simplicity, oxide homojunctions thus show considerable promise as a platform for tunable complex magnetism and as a powerful design element of spintronic devices.
Volatile Organic Compound Sensing Array and Optoelectronic Filter System using Ion‐Pairing Dyes with a Wide Visible Spectrum
Authors: Kim Donghyun , Hwang Ki‐Seob , Koh Won‐Gun , Lee Chanmin , Lee Jun‐Young
Published: July 2022

An ideal dye‐based sensing array has essential design requirements, including facile preparation methodology, tolerance to water vapor, a broad range of color‐responsive changes, and a simple readout system. Here, a brief synthetic route is developed for ion‐pairing dyes exhibiting unusual chromatic changes across the entire visible spectrum. It requires only mixing and precipitation under mild conditions. The dyes are applied to a sensing array containing 12 sensing elements with different initial states. Owing to the numerous color variations of the dyes, the color map generated by the array is highly simple yet sufficiently accurate to distinguish among the different functional groups (such as amines, aldehydes, and carboxylic acids) as well as carbon chain lengths. Principle component analysis (PCA) demonstrates that volatile organic compounds (VOCs) can be well classified according to the color changes of the sensing array. The ion‐pairing dyes are embedded into 3D stacked nanofibers via electrospinning, and function as effective harmful‐gas (e.g., formaldehyde) sensors with sub‐ppm theoretical detection limits (0.15 ppm). Finally, the 3D stacked nanofibers can be employed in an optoelectronic filter system that automatically checks for formaldehyde in the surroundings and also confirms the effective removal of the detected formaldehyde by the gas filter cartridge.
Self‐Sacrificially Degradable Pseudo‐Semiconducting Polymer Nanoparticles that Integrate NIR‐II Fluorescence Bioimaging, Photodynamic Immunotherapy, and Photo‐Activated Chemotherapy
Authors: Tang Dongsheng , Yu Yingjie , Zhang Jinbo , Dong Xiying , Liu Chaoyong , Xiao Haihua
Published: July 2022

Semiconducting polymers (SP) hold great promise for cancer phototherapy due to their excellent optical properties; however, their clinical application is still hampered by their poor biodegradability. Herein, a self‐sacrificially biodegradable pseudo‐semiconducting polymer (PSP) for NIR‐II fluorescence bioimaging, photodynamic immunotherapy, and photoactivated chemotherapy (PACT) is reported. The PSP can further co‐assemble with an amphiphilic polyester with pendant doxorubicin (DOX) in its side chains via reactive oxygen species (ROS)‐responsive thioketal linkages (PEDOX), which are denoted as NP@PEDOX/PSP. The NP@PEDOX/PSP can accumulate at tumor sites and generate ROS for photodynamic immunotherapy as well as near‐infrared‐II fluorescence (NIR‐II) for bioimaging upon irradition at 808 nm. The ROS could break up thioketal linkages in PEDOX, resulting in rapid doxorubicin (DOX) release for PACT. Finally, both PEDOX and PSP are degraded sacrificially by intracellular glutathione (GSH), resulting in the dissociation of NP@PEDOX/PSP. This work highlights the application of self‐sacrificially degradable PSP for NIR‐II fluorescence bioimaging, photodynamic immunotherapy, and PACT in cancer therapy.
FeNi@N‐Doped Graphene Core–Shell Nanoparticles on Carbon Matrix Coupled with MoS2 Nanosheets as a Competent Electrocatalyst for Efficient Hydrogen Evolution Reaction
Authors: Shah Sayyar Ali , Xu Li , Sayyar Rani , Khan Iltaf , Yuan Aihua , Shen Xiaoping , Li Xiaohong , Ullah Habib
Published: July 2022

Synthesis of noble‐metal‐free electrocatalysts for green hydrogen production is crucial to overcoming the energy demand of modern society. One of the most competitive and alternative noble‐metal‐free electrocatalysts for hydrogen evolution reaction (HER) is molybdenum disulfide (MoS2)‐based composites. Herein, it is shown that MoS2 nanosheets grow on FeNi@N‐doped graphene nanoparticles/N‐doped carbon matrix (FeNi@NG/NCM@MoS2), using the hydrothermal method. FeNi@NG/NCM@MoS2 hybrid displays outstanding HER performance with a low overpotential of 79 mV at 10 mA cm−2, a small Tafel slope of 40.2 mV dec−1, and high durability. First‐principles density functional theory simulations confirm the electron transformation from FeNi alloy to NG surface of FeNi@NG particle and subsequently further transfer to MoS2 nanosheets, which decrease the Gibbs free energy (ΔGH* ≈ −0.08 eV) and local work function for enhanced HER activities. This work highlights the understanding of electron transfer in demonstrating the kinetic reaction of the HER process and offers a new avenue for constructing efficient MoS2‐based electrocatalysts.
Robust Deposition of Sub‐Millimeter WSe2 Drive Ultrasensitive Gate‐Tunable 2D Material Photodetectors
Authors: Yang Mengmeng , Luo Zhongtong , Gao Wei , Zhang Menglong , Huang Le , Zhao Yu , Yao Jiandong , Wu Fugen , Li Jingbo , Zheng Zhaoqiang
Published: July 2022

2D semiconductors are regarded as the potential channel materials for high‐performance integrated optoelectronics. However, the absence of an effective photoconductive gain mechanism and the adverse effects from traditional SiO2 substrate prevent the further breakthrough of the photosensitivity of 2D semiconductors‐based photodetectors. Here, an ingenious out‐of‐plane heterostructure is proposed for boosting the photosensitivity. Sub‐millimeter scale (>700 µm) tri‐layer WSe2 with high quality and uniformity is robustly deposited and integrated with 2D photosensitive channels for gate‐tunable photodetection. The WSe2 with naturally passivated surface can not only serve as a substrate passivation layer to mitigate the detrimental substrate effects, but also introduces vertical built‐in fields, which efficiently separates the photogenerated carriers and produces high photoconductive gain. Under gate voltage modulation, the proposed InSe photodetector exhibits a series of excellent performances, including responsivity of 112 A W−1, detectivity of 8.6 × 1012 Jones, light on/off ratio of 1.3 × 104 and rise/decay time of 29.1/15.3 ms. More inspiringly, this heterostructure scheme is universally applicable to 2D WS2 photodetector and also significantly improves its photosensitivity, demonstrating broad applicability. This research will provide helpful guidance for the design and optimization of customizable optoelectronic devices based on 2D semiconductors.
Triangular Micro‐Grating via Femtosecond Laser Direct Writing toward High‐Performance Polarization‐Sensitive Perovskite Photodetectors
Authors: Tian Xiaoyu , Wang Ruonan , Xu Yalun , Lin Qianqian , Cao Qiang
Published: July 2022

Thanks to attractive properties, such as defect tolerance, broad bandgap tunability, high quantum yields, and large absorption coefficient, perovskites have emerged as a star material in the past decade. Meanwhile, optical nano/microstructures made of perovskites offer a facile and efficient strategy to improve light‐harvesting performance and sensitivity of polarization. However, there is no low‐cost, high‐accuracy, and reproducibility technique for large‐scale fabrication of perovskite nano/microstructures. Here, femtosecond laser direct writing technique is introduced to fabricate FAPbI3 perovskite micro‐grating. Based on precise spatial and power control of femtosecond laser, micro‐grating with different structure parameters (period and depth) can be processed and investigated. Triangular micro‐grating of perovskite exhibits excellent emission properties (up to 67 times enhancement) owing to low reflectance and high absorption intensity. Strikingly, the outstanding performance of perovskite triangle grating photodetectors is obtained. The responsivity and detectivity reach 11.7 A W−1 and 7.8 × 1012 Jones, which are ≈3 and 12 times larger than the control devices;  they also exhibit lower noise and decent polarization sensitivity. Taking the advantages of low cost, high accuracy, and reproducibility, the femtosecond laser direct writing technique endows perovskite materials with micro‐photonic concept and remarkably enhances the devices’ performance.
A Sphingolipid Fatty Acid Constituent Made by Alkyne trans‐Hydrogenation: Total Synthesis of Symbioramide
Authors: Radkowski Karin , Fürstner Alois
Published: July 2022

A scalable approach to (2R)‐hydroxyoctadec‐3‐enoic acid ((−)‐2) is reported, which is the fatty acid constituent of numerous sphingolipids of biological significance. Key to success was the chemoselective trans‐hydrogenation of a functionalized propargylic alcohol precursor with [Cp*RuCl]4 as the catalyst, followed by lipase‐catalyzed resolution of the racemic product. (−)‐2 then served the shortest total synthesis of the marine natural product symbioramide known to date.

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Cobalt‐Catalyzed Selective Transformation of Levulinic Acid and Amines into Pyrrolidines and Pyrrolidinones using Hydrogen
Authors: Pan Yixiao , Luo Zhenli , Yang Ji , Han Jiahong , Yang Jianbo , Yao Zhen , Xu Lijin , Wang Peng , Shi Qian
Published: July 2022

Cobalt‐catalyzed selective transformation of levulinic acid and primary amines into pyrrolidines and pyrrolidinones under H2has been developed. The catalyst system consisting of Co(NTf2)2, 1,1,1‐tris(di(4‐methoxyphenyl)phosphinomethyl) ethane ((p‐anisyl)triphos) and Me3SiOTf works well for the synthesis of pyrrolidines via reductive amination/cyclization/deoxygenative reduction of amide, and using Co(NTf2)2/1,1,1‐tris(diphenylphosphinomethyl) ethane (triphos) as the catalyst under reduced hydrogen pressure results in exclusive formation of pyrrolidinones. Both aryl and alkyl primary amines are suitable substrates, and a variety of functional groups are tolerated. Meanwhile, 4‐oxo‐4‐arylbutanoic acids, 5‐oxohexanoic acid, 6‐oxoheptanoic acid, 2‐formylbenzoic acid, 2‐acetylbenzoic acid and 2′‐acetyl‐[1,1′‐biphenyl]‐2‐carboxylic acid are also applicable, allowing for convenient access to cyclic amines and lactams with different ring size.

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Efficient and Durable Sodium, Chloride‐doped Iron Oxide‐Hydroxide Nanohybrid‐Promoted Capacitive Deionization of Saline Water via Synergetic Pseudocapacitive Process
Authors: Zhao Jingxuan , Wu Bingyao , Huang Xinwei , Sun Yang , Zhao Zhibo , Ye Meidan , Wen Xiaoru
Published: July 2022

Recently, the rational design and development of efficient faradaic deionization electrodes with high theoretical capacitance, natural abundance, and attractive conductivity have shown great promise for outstanding capacitive deionization (CDI)‐based desalination applications. Herein, the construction of novel FeOOH hybrid heterostructures with Na and Cl dopants (e.g., Na‐FeOOH and Cl‐FeOOH) via a robust hydrothermal strategy is reported, and an asymmetric CDI cell (Na‐FeOOH//Cl‐FeOOH) comprising Na‐FeOOH and Cl‐FeOOH working as the cathode and anode, respectively, is assembled. The multiple coupling effects of the specific structural features (e.g., enriched porosity, hierarchical pore alignment, and highly open crystalline framework), enhanced electrochemical conductivity, and optimized ion‐transfer property endow the FeOOH hybrid electrode with improved electrochemical performance. Impressively, the Na‐FeOOH//Cl‐FeOOH cell demonstrates a superior salt adsorption capacity (SACNaCl) of 35.12 mg g−1 in a 500 mg L−1 NaCl solution, a faster removal rate, and remarkable cycling stability. Moreover, the pseudocapacitive removal mechanism from the synergetic contribution of the Na‐FeOOH cathode and Cl‐FeOOH anode account for the significant desalination promotion of the Na‐FeOOH//Cl‐FeOOH cell.
Achieving purely organic room temperature phosphorescence in aqueous solution
Authors: Sun Hao , Zhu Liangliang
Published: July 2022

Purely organic room temperature phosphorescence (RTP) materials have aroused increasing interests in recent years and have been widely applied in anti‐counterfeiting, biological imaging, sensing, etc. Currently, these materials can be efficiently developed in crystalline states and amorphous polymer‐doped systems. However, achieving organic RTP in solution, especially in water solution, is still a formidable challenge. Recently, reports on aqueous phase RTP have been increasing and some feasible design strategies have been proposed; however, related investigations are still limited and there is a lack of systematic reviews. Therefore, we summarized the recent cases of aqueous phase organic RTP emission with primarily focusing on the RTP properties and efficient design strategies (e.g., forming nanoparticles from phosphorescent molecules and macrocyclic supramolecular assembly). Moreover, promising applications of the aqueous phase organic RTP emission in bio‐imaging and sensing were discussed. Some detailed perspectives concerning materials design and application were provided with the hope to provide inspiration for the future development of aqueous phase organic RTP.
Whither chemical engineering?
Authors: Ramkrishna Doraiswami , Braatz Richard D.
Published: July 2022

The 1988 Amundson Report on research needs in chemical engineering encouraged the pursuit of frontier areas in chemical engineering with the warning, however, that attention to core areas must be preserved. Indeed, the strong core base in chemical engineering during the latter half of the 20th century enabled chemical engineers to contribute extensively to many areas outside of the traditional. The depth of such involvement has led researchers to confront questions much more engaging to the field of application. This effort has led to adopting and cultivating expertise more native to the field of application than to secure chemical engineering as a discipline. It therefore seems appropriate to ask if the warning voiced in the Amundson Report needs to be reiterated. If chemical engineering research must leave a strong trail of fundamental understanding through developed methodologies to ensure continuing progress, then this article yields considerable scope for discussion.