bluuebunny/crossref_metadata_2025 huggingface dataset:
Avaliação de locais potenciais para instalação de torres de observação para prevenção de risco de incêndios florestais
Authors: Moreira Pedro Augusto Gonzaga , Mendes Thiago Augusto , Santos Diego Fonseca dos
Published: April 2021

A grande incidência de incêndios florestais observados em Unidades de Conservação faz com que esse evento se torne uma ameaça à proteção dessas áreas. Este artigo apresenta o mapeamento de áreas suscetíveis a incêndios florestais, bem como a identificação de locais potenciais para instalação de torres de vigilância de incêndios florestais para os parques Estaduais Altamiro de Moura Pacheco e João Leite e área de entorno de 3,0 km de extensão a partir dos limites dos parques, utilizando ferramentas SIG livres. O mapa final de risco de incêndios foi obtido através da sobreposição ponderada dos principais fatores relacionados com incêndios florestais, como: declividade, hipsometria, orientação das encostas, malha viária e trilhas, perímetro urbano, uso do solo, temperatura, umidade e exposição aos ventos. Para determinação de locais potenciais para implantação de torres de observação de incêndios foram considerados os seguintes fatores: relevo (cotas de maior altitude), proximidade das estradas, proximidade com as regiões classificadas com risco moderado e alto e uso do solo. Os resultados mostraram que 9.724,66 ha (41,4%) das áreas dos parques avaliados possuem alto risco de incêndios. O mapa de risco de incêndios foi validado considerando os focos de calor disponibilizados pelo INPE (2017), obtendo mais de 60% de precisão em relação às áreas de risco alto. Com relação aos locais indicados para instalação das torres de observação de incêndios, a instalação apenas de uma torre proporcionou a maior visualização das áreas de estudo, 56,1%. Combinando a instalação de duas torres, foi possível obter cobertura de visualização de 71,1% de toda as áreas de estudo. Dessa forma, demostrou-se que a gestão e tomada de decisões ambientais referente ao monitoramento de riscos de incêndios florestais em regiões protegidas podem ser mais bem-sucedidas quando complementadas com ferramentas de geotecnologias.
Degradação de geotêxteis de Typha latifolia Linn utilizados em técnicas de bioengenharia de solos
Authors: Holanda Francisco Sandro Rodrigues , Castro João Deverton Santos de , Santos Luiz Diego Vidal , Andrade Carlos Eduardo Celestino de , Griza Sandro , Rodrigues Junior José Joatan , Pedrotti Alceu
Published: April 2021

O uso das fibras da taboa (Typha latifolia Linn), para confecção de geotêxteis, tem sido trabalhada, buscando a estabilização de taludes de rios ou encostas, e assim criando um ambiente ecologicamente favorável para a recuperação da vegetação e a ancoragem do solo. O objetivo deste trabalho foi avaliar a resistência e durabilidade de geotêxteis fabricados com fibras da taboa submetidos ao envelhecimento acelerado em laboratório e degradação dessas fibras em campo. A confecção dos geotêxteis foi realizada com diferentes nós em fibras que passaram previamente por processos de secagem distintos. Para a realização dos testes em laboratório, foi construído aparato que permitiu submeter os corpos de prova ao envelhecimento precoce, buscando simulação das condições ambientais, isto é, as fibras foram expostas à radiação UVB seguida de condensação, utilizando-se também um resfriador mecânico para equalização da temperatura. Os ensaios de resistência à tração seguiram diretrizes observadas nas normas ISO 10319 (1996) e ISO 12236 (1998). Os ensaios de campo foram conduzidos por disposição de amostras em um talude da margem direita do rio São Francisco no município de Amparo do São Francisco-SE, 10°08'20.7"S 36°54'47.0"W, Nordeste do Brazil, com área de 20m2, submetidas às condições climáticas locais, para posterior avaliação da sua degradação. Uma vez que os materiais não apresentam homogeneidade na sua fabricação, ocorreram resultados não uniformes quando submetidos à degradação. Isso pode explicar o fato de serem observados aumentos inesperados nos valores de tensão e deformação. O geotêxteis de taboa apresentou resultados de tensão de ruptura e deformação que sinaliza positivamente para o seu uso comercial, confirmando, assim, as suas potencialidades para uso como parte das técnicas de bioengenharia de solos.
Effect of different inoculations on biogas and methane production through anaerobia biodigeston using residues from the avícola sector
Authors: Bortolini Joseane , Tavares Maria Hermínia Ferreira , Silva Ana Claudia Guedes , Freitag Dayane Taine , Fleck Leandro , Kuczman Osvaldo
Published: April 2021

The present study aimed to analyze the use of different digestates as inocula for the anaerobic digestion of poultry litter, evaluating the biogas and methane production. The inocula used were: bovine and porcine biofertilizer; with feeding loads of 0.67, 1.00 and 1.67 gVS L-1 day-1. Statistical analyses followed a split-plot design, where the main plot being inoculum and the feeding load as secondary. The experimental data were submitted to analysis of variance, at the level of 5% of significance. The following variable responses were considered: biogas production, specific biogas production as a function of volatile solids (VS) added to the biodigester, specific biogas production as a function of organic load, in terms of COD, and methane production. The highest rates of average biogas production, specific biogas production by VS added, specific production of biogas as a function of COD, and average methane production occurred with the use of bovine inoculum. Through the analysis of the total average percentage of methane production, productions of 63.0% and 54.5% for bovine and swine inoculum. Considering the results obtained, the use of bovine inoculum for the process of anaerobic digestion of poultry litter is recommended vinculado a produção de biogás e metano.
Chemical characterization, toxicity, antioxidant and antimicrobial activity of the essential oils of Hymenaea courbaril L. and Syzygium cumini (L.) Skeels
Authors: Everton Gustavo Oliveira , Pereira Ana Patrícia Matos , Rosa Paulo Victor Serra , Mafra Nilton Silva Costa , Santos Júnior Paulo Sérgio , Souza Franscristhiany Silva , Mendonça Caritas De Jesus Silva , Silva Fernando Carvalho , Gomes Paulo Roberto Barros , Mouchrek Filho Victor Elias
Published: April 2021

This study evaluated the antimicrobial, antioxidant and toxicity activity of essential oils (EOs) of Hymenaea courbaril L. var. courbaril bark and Syzygium cumini (L.) Skeels leaves. The EOs were extracted by hydrodistillation and chemically characterized by gas chromatography coupled to mass spectrometry (GC/MS). The ABTS and DPPH assay were used to evaluate antioxidant activity. For the toxicity assay, lethality was evaluated against Artemia salina Leach. For the antimicrobial assay, the method of Disc Diffusion and Dilution in Broth was applied to obtain the minimum inhibitory concentration and minimum bactericidal. The major constituent of the EO of H. courbaril was β-ocimene (23.33%) and the EO of S. cumini was isocaryophyllene (18.01%). Both OE showed relevant antioxidant activity and low toxicity against Artemia salina. The EOs showed bactericidal activity against E. coli, S. aureus, P. aeruginosa, Salmonella sp., B. cereus and P. mirabilis. The results obtained are encouraged by the potential use of the OE's studied in the control and fight of pathogenic microorganisms.
Estrategias curatoriales para expografías virtuales. Cómo pensar alternativas por fuera de la hipermediatización
Authors: Szlifman Mariel
Published: April 2021

¿Qué implica curar y exhibir para el espacio virtual en tiempos de pandemia? ¿Cómo consumimos arte en la era de la hipermediatización? Este ensayo propone reflexionar sobre los procesos curatoriales y museográficos de los espacios de arte durante el aislamiento social, preventivo y obligatorio ante la pandemia global del 2020, revisitando el dispositivo de la exposición artística. Contemplando algunas teorías de la crítica curatorial y problemáticas actuales de la experiencia en los museos contemporáneos, convocamos conceptos del campo del diseño y de los medios digitales para pensar qué modos y experiencias se activan en el espacio virtual de una muestra. Considerando que nos encontramos inmersos en un panorama postmedial, sugerimos pensar las expografías virtuales a través de la idea de narrativas transmedia, las cuales habilitan múltiples dispositivos mediales de distribución y nuevas estrategias curatoriales que expandan las prácticas museográficas tradicionales pensadas para la sala y el encuentro físico con el espectador. De este modo, a partir de algunos casos de referencia de galerías, museos y espacios de arte de Latinoamérica, reflexionamos sobre estrategias de tiempo y espacio para la navegación de muestras online, que construyan entornos virtuales estimulantes para los espectadores devenidos en usuarios.
Curadoria digital urbana, rebelião monumental e a disrupção das narrativas patrimoniais em tempos de isolamento
Authors: Graziosi Casimiro Giovanna
Published: April 2021

Este artigo, no campo da teoria da arte e da arquitetura debate as novas formas da curadoria digital na cidade e o surgimento de narrativas urbanas que questionam os poderes vigentes, caso do ataque recente a monumento colonialista pelo mundo e sua associação a cultura digital. Para este debate, discute-se o fortalecimento do setor privado digital durante a pandemia e se propõe pensar a nova condição da cidade em meio ao isolamento e distanciamento físico, derivado do COVID-19. Deste modo, propõe-se discutir o termo curadoria digital urbana e a revisão patrimonial em curso, refletida na remoção e ataque a monumentos pelo mundo. A remoção e o ataque coletivo aos monumentos é um marco nos modos de operar a memória urbana que revisa a construção linear da narrativa histórica, colocando em cheque a calcificação memorial. A relação entre cidadãos e os modos de habitar a cidade se transformam à medida em que as superfícies são redesenhadas pela cultura e mercado digital. A tomada da cidade pelo território informacional, gera um lapso da percepção espaço-temporal, impactando a linearidade do tempo, as narrativas e até mesmo a historicidade em seus moldes tradicionais. Deste modo, este artigo discute o impacto destas condições sobre o patrimônio, o questionamento das narrativas expostas na cidade,  e o contraditório estabelecimento das memórias digitais na vida cotidiana.
The veridical travel of the truly imaginary plant: Curatorial approach and underlying ideas
Authors: De Menezes Marta , Schnugg Claudia , Buread Annick , Šebjanič Robertina , Kourochkina Tatiana
Published: April 2021

O projecto The Traveling Plant é um projecto colaborativo que se desenvolve através de uma rede global e tem o objectivo de ser partilhado localmente. Pretende lidar de uma perspectiva composta numa série de ações que impactam o global e vivem na localidade, transparecendo e projetando uma variedade de modos de fazer e de ver; de modo a abraçar a dualidade de práticas partilhadas e troca de saberes presente numa rede distribuída de forma virtual e física/não-virtual. Procura lidar com as questões de um fazer concentrado em perspectivas para além do simplesmente humano, que incluem o não-humano e procuram evitar formas colonialistas e antropocénicas de agir e estar. Este artigo apresenta uma estratégia curatorial e as suas questões adjacentes que o grupo de comissárias toma como ponto de partida, a estrutura organizacional para o desenvolvimento do projeto e clarifica como se vai desenrolar.
Laser irradiation in aviation transport
Authors: Korecki Zbyšek
Published: April 2021

The high level of security and safety areas in air transport is due to the continuous detection of threats and risks and the adoption of measures to cut them. The media significance of aviation attacks and the potential threat to passengers and crew leads responsible national and international authorities to carry out measures across states. The active operation of the pilot is most important in the phases when the pilot performs manual control or when dealing with emergency and emergency situations. Laser attacks on aircraft are most often recorded in phases takeoff and landing up to a height of 400 feet. In recent years, attacks have also occurred against aircraft at high flight levels of 9-10 km. Lasers have a power of about 1W and are used on automatic monitoring devices. The pilot's higher vulnerability is during the landing phase when illumination from the left side into the cockpit can significantly affect the pilot's ability to maneuver manually. Lasers are devices that emit coherent radiation in the optical spectral band 532nm  . Green lasers emitting at a wavelength are most often used to attack aircraft. A more detailed division is given by the harmfulness of laser radiation. Radiation harmfulness is assessed according to the Maximum Permissible Exposure (MPE). MPE can be expressed in two quantities, the highest power density (W/m3), or the energy density of the light source (J/cm2). In case of influence on the pilot in selected phases of flight, it is eyes exposure MPE. The theoretical description of the effects of lasers during the approach to landing will be supplemented by maps of protection zones with the laser devices prohibition according to regulation L-14. The analysis will be performed for international non-public controlled airports of the Czech Republic with IFR operations.
Defesa psíquica na primeira tópica freudiana: por que as pulsões são reprimidas?
Authors: Sanches Aline , Bocchi Josiane Cristina
Published: April 2021

Desde o início da teorização freudiana, inibição, defesa e censura são processos que devem incidir sobre as pulsões. O primitivo pulsional precisa ser reprimido ou transformado. Este artigo problematiza a relação entre as pulsões sexuais e a defesa psíquica, ao longo do período pré-psicanalítico e da primeira tópica freudiana. Situamos o conflito entre sexualidade e repressão, apontado por Freud como característico das psiconeuroses, enquanto que nas neuroses atuais a angústia está relacionada a um registro quantitativo e não exatamente a um conflito psíquico. Nesse caso, revela-se desencontros entre um sexual corpóreo e sua representação psíquica. Pretende-se, neste trabalho, evidenciar o caráter negativo das pulsões e pôr em relevo a natureza do antagonismo que se opõe às pulsões sexuais. A formulação das pulsões de autoconservação como aquilo que deve se contrapor às pulsões sexuais não esclarece completamente porque é imperativo que algo aconteça face às vivências pulsionais fundantes do aparelho. A satisfação em estado bruto acarreta prejuízos, tanto do ponto de vista psíquico quanto social; logo, a repressão das pulsões sexuais é condição necessária para a existência individual e coletiva. Evidencia-se assim algo específico do humano, afinal, se toda a natureza funciona afirmando o instinto, a espécie humana somente se desenvolve a partir de sua negação. A partir de tais construções teóricas, questiona-se se a psicanálise ainda permanece demasiadamente tributária de uma concepção de natureza revestida de pressupostos morais, sustentando a noção de que tenha que ser continuamente negada, afastada, coagida e domesticada, em prol de construções sociais bastante questionáveis, porém acatadas como necessárias.
Uma Genealogia da Biopolítica: A Noção de Vida em Canguilhem e Foucault
Authors: Muhle Maria
Published: April 2021

No primeiro volume de História da Sexualidade, Michel Foucault apresenta o que iria tornar-se um conceito polêmico em sua obra, bem como para seus intérpretes. Desde então, a noção de biopolítica tem polarizado as leituras da teoria de poder de Foucault e talvez haja desempenhado um papel bem mais importante do que ele jamais pretendeu. Para propor um estudo genealógico do termo “biopolítica”, é importante olhar mais de perto a noção de vida que pode haver inspirado a análise foucaultiana. Foucault opera com uma noção de vida que ele não determina: vida é um correlato de técnicas e estratégias de poder e de saber, ela carece de qualquer status ontológico e é ela mesma “produzida” pela constelação de poder-saber.
Factors Affecting Farm Income of Different Farming System in Madhya Pradesh
Authors: Tiwari Yogesh , Sharma H. O. , Awasthi P. K. , Kolar Prasanna
Published: April 2021

The present study was conducted in Umaria and Anuppur districts of Madhya Pradesh with the specific objective viz. to examine the factors influencing farm income of the respondents. The study confined to two locations of AICRP on IFS, JNKVV, Jabalpur. Total 240 respondents, consisted of 120 beneficiaries under IFS and 120 non-beneficiaries with similar socio economic, were involved in this work. The log linear form of Cobb-Douglas production function was applied to determine the effects of socio-economic variables on farm income. Apart from this, some descriptive statistical analyses were carried out to examine the socio-economic characteristics of the households. The estimated results of the regression models revealed that land holding, irrigation intensity, cost of farm inputs and employment generation had a significant positive effect on farm income among beneficiary’s respondents. On the other hand, age, education, cost of farm inputs and employment generation had a significant positive effect on farm income among non-beneficiary’s respondents. The results of the present study help in increasing the farm income by the enhancement of the factors which found significant during the study period and the policy makers can also plan accordingly for the betterment of both the respondents.
Arterial Blood Gas Analysis of Critically Ill Corona Virus Disease 2019 Patients
Authors: Lakhani Jitendra , Kapadia Sajani , Pandya Hetal , Gill Roop , Chordiya Rohit , Muley Arti
Published: April 2021

Background/Aims: The aim of present study was to find out profile and sequential pattern of Arterial Blood Gas (ABG) in critically ill Corona Virus Disease 2019 (COVID-19) patients.

Study Design: Observational prospective study.

Methodology: A total of 80 Reverse Transcription Polymerase Chain Reaction (RT PCR) positive cases; that needed ICU admission for their life-threatening conditions were included in this study done at teaching hospital of Gujarat, India. Non consenting patients and patients who could not be followed up as per protocol were excluded. Data of Arterial Blood Gas (ABG), performed on admission, day 5 and day 10 were taken for the analysis. Patients were followed up till they remained in ICU.

Results: Of 80 patients, 3 patients had normal, 24 patients (30%) had primary disorder on ABG while 53 patients (66.25%) had mixed disorders. The most common ABG abnormality observed was respiratory alkalosis with metabolic acidosis in 16 patients (20%) while respiratory alkalosis with metabolic alkalosis in 15 patients (18.75%). There was difference in ABG pattern observed among survivors and non-survivors (P=.04); of which conspicuous was presence of “respiratory acidosis with metabolic acidosis” in 5 non-survivors (15.63%), which was not seen in survivors. Of 80 patients admitted in COVID ICU; 2 improved after day 1; 6 after day 5; 40 after day 10, making total of 48 patients surviving COVID critical condition. Of 32 non-survivors, 14 died within twenty-four hours of admission, 14 within first 5 days and 04 after 10 days of ICU stay.

Conclusion: ABG done on admission and serially in severe COVID-19 patients gives useful information on underlying pathophysiology. Mixed ABG pattern was more common than single disorder which can be sign of multi-organ involvement.  Respiratory acidosis with metabolic acidosis was observed significantly higher in non-survivors. Respiratory alkalosis as a part of single or mixed pattern on ABG was the most common pattern found in critically ill COVID patients.
The Extent of Premarital Sex Practices among Secondary Schools Adolescents in Local Government Area of Ebonyi State, South Eastern Nigeria
Authors: Aleke Christian O. , Obande-Ogbuinya Edith N. , Omaka-Amari Lois N. , Eunice Afoke N. , Igwenyi Precious I. , Nwafor Jude N. , Okeke Ifeyinwa M. , Nchita Ferdinand S.
Published: April 2021

Aims: This study aimed at determining the extent of premarital sex practices among secondary school adolescents in Ikwo Local Government Area of Ebonyi State. Its objectives were to reveal the extent at which secondary school students engage in premarital sex in the area and how such practices can propel risky behaviors among them.

Study Design: The descriptive survey research design was adopted for the study.

Methodology: Multi-stage sampling procedure was used to select 844 secondary school adolescents for the study. Information was retrieved from the field through questionnaire administration. Means and standard deviation were used to answer the research questions while the chi-square statistical tool was used in testing the null hypotheses in the study.

Results: The result showed that the premarital sex in the study was at low extent with the grand mean score x̅=2.26. However, the result indicated that 16% of the students engage in penetrative virginal sex, anal sex, oral sex and masturbation whereas 84% of the students do not.

Recommendation: The study recommended among others that: All the head teachers and principals should play an active role by coming up with awareness program through seminar, rallies with strong guidance on dangers associated with premarital sex. Also, parents should always discus sex education with their children to be adequately informed with the right information about sex and the behaviour to adopt as they grow to puberty period to avoid engaging in premarital sexual practice at this early stage.
Knowledge, Attitude and Practice of Dentists towards Dental Procedures under General Anesthesia in Children
Authors: Keerthika S. , Mani Geo
Published: April 2021

General anaesthesia is used in routine pediatric dental practice. Although they are considered effective and safe in controlling pain during dental procedures, complications related to their use appear inevitable. Aim of the study was to assess knowledge, attitude and practice of dentist towards dental procedures under general anesthesia. It was a university setting study. Questionnaires consisting of ten questions [Fig. 1] focused on the perceptions and experiences on protocols followed by general dental practitioners and specialists on general anesthesia. Data was entered in excel in a methodical manner and was imported to SPSS software 20. Chi square association was done to compare the responses between general dentist and specialist and were represented in the form of bar graphs. In relation to association between Qualification and common indications of general anaesthesia. (Pearson Chi Square = 2.789, P value = 0.425(<0.05), hence statistically not Significant). Among General dentists, 37.5% of them agreed with Extreme non- cooperation followed by 25% for long surgical procedures and strong emetic and 12.5% for Extreme dental fear as a common indication for general anesthesia. Among Specialists, 38.2% of them agreed with long surgical procedures followed by 35.2% for extreme non cooperation, 17.6% for extreme dental fear and 8.82% for strong emetic reflex as a common indication for general anesthesia [Fig. 5]. Both General dentist and specialist have fairly good knowledge about paediatric general anaesthesia.
Live Chat Analysis Using Machine Learning
Authors: Kavibharathi S. , Priyankaa S. Lakshmi , Kaviya M.S. , Vasanthi Dr.S.
Published: April 2021

The World Wide Web such as social networking sites and blog comments forum has huge user comments emotion data from different social events and product brand and arguments in the form of political views. Generate a heap. Reflects the user's mood on the network, the reader, has a huge impact on product suppliers and politicians. The challenge for the credibility of the analysis is the lack of sufficient tag data in the Natural Language Processing (NLP) field. Positive and negative classify content based on user feedback, live chat, whether the user is used as the base for a wide range of tasks related to the text content of a meaningful assessment. Data collection, and function number for all variants. A recurrent neural network is very good text classification. Analyzing unstructured form from social media data, reasonable structure, and analyzes attach great importance to note for this emotion. Emotional rewiring can use natural language processing sentiment analysis to predict. In the method by the Recurrent Neural Networks (RNNs) of the proposed prediction chat live chat into sentiment analysis. Sentiment analysis and in-depth learning technology have been integrated into the solution to this problem, with their deep learning model automatic learning function is active. Using a Recurrent Neural Networks (RNNs) reputation analysis to solve various problems and language problems of text analysis and visualization product retrospective sentiment classifier cross-depth analysis of the learning model implementation.
Non‐Halogenated‐Solvent Processed and Additive‐Free Tandem Organic Solar Cell with Efficiency Reaching 16.67%
Authors: Qin Shucheng , Jia Zhenrong , Meng Lei , Zhu Can , Lai Wenbin , Zhang Jinyuan , Huang Wenchao , Sun Chenkai , Qiu Beibei , Li Yongfang
Published: April 2021

Organic solar cells (OSCs) have recently reached a remarkably high efficiency and become a promising technology for commercial application. However, OSCs with top efficiency are mostly processed by halogenated solvents and with additives that are not environmentally friendly, which hinders large‐scale manufacture. In this study, high‐performance tandem OSCs, based on polymer donors and two small‐molecule acceptors with different bandgaps, are fabricated by solution processing with non‐halogenated solvents without additive. Importantly, the two active layers developed from non‐halogenated solvents show better phase segregation and charge transport properties, leading to superior performance than halogenated ones. As a result, a tandem OSC with high efficiency of up to 16.67% is obtained, showing unique advantages in future massive production.
A Systematic Strategy of Combinational Blow for Overcoming Cascade Drug Resistance via NIR‐Light‐Triggered Hyperthermia
Authors: Wang Lingna , Yu Yingjie , Wei Dengshuai , Zhang Lingpu , Zhang Xiaoyan , Zhang Guanxin , Ding Dan , Xiao Haihua , Zhang Deqing
Published: April 2021

A systematic combination strategy is proposed for overcoming cisplatin resistance using near‐infrared (NIR)‐light‐triggered hyperthermia. A new photothermal polymer DAP‐F is complexed with a reduction‐sensitive amphiphilic polymer P1 to form F‐NPs with photothermal effect. Subsequently, to build the final nanosystem F–Pt‐NPs, F‐NPs are combined with Pt‐NPs, which are obtained by encapsulating a Pt(IV) prodrug with P1. Mild hyperthermia (43 °C), generated from F–Pt‐NPs induced by an 808 nm NIR laser, have various effects such as: i) enhancing the cellular membrane permeability to promote the uptake of drugs; ii) activating cisplatin by accelerating the glutathione consumption; iii) increasing the Pt‐DNA adducts formation and possibly the formation of a portion of irreparable Pt‐DNA interstrand crosslinks, thereby inhibiting the repair of DNA. In vitro, it is found that even on cisplatin‐resistant A549DDP cells, the IC50 of F–Pt‐NPs (43 °C) is only 7.0 × 10−6 m Pt mL−1. In vivo, on a patient‐derived xenograft model of multidrug resistant lung cancer, the efficacy of the F–Pt‐NPs (43 °C) treatment group shows a tumor inhibition rate of 94%. Taken together, here, an important perspective of resolving cascade drug resistance with the assistance of mild hyperthermia triggered by NIR light is presented, which can be of great significance for clinic translation.
Fast Flexible Bottom‐Gated Hydrogen Sensor Based on Silicon Nanomembrane
Authors: Cho Minkyu , Cho Incheol , Kim Kyuyoung , Park Inkyu
Published: April 2021

High performance flexible hydrogen sensor using a silicon nanomembrane (Si NM) coated with palladium nanoparticles (Pd NPs) is developed. After the formation of gate structure on a released Si NM, selectively pre‐doped Si NM is flip‐transferred onto a plastic substrate. Along with Pd NPs deposited on top of the Si channel, the bottom gate structure allows the sensor to operate in a sub‐threshold regime maximizing the response and recovery speed. A device simulation study revealed that the current change caused by shifting the threshold voltage upon H2 exposure is the main operating mechanism of the sensor. The fabricated sensor shows high response (up to 250% @ 0.7% H2 concentration), short response time (τ10–90 = 10 s), and short recovery time (τ90–10 = 10 s). In addition, the sensor shows low detection limit (50 ppm) and high mechanical robustness.
Synthesis of γ‐Keto Sulfones through a Three‐Component Reaction of Cyclopropanols, DABCO ⋅ (SO2)2 and Alkyl Halides
Authors: Zhang Chun , Zhang Chao , Tang Jie , Ye Shengqing , Ma Mingliang , Wu Jie
Published: April 2021

A route to γ‐keto sulfones through a metal‐free reaction of cyclopropanols, DABCO ⋅ (SO2)2 and alkyl halides is described. This reaction occurs under mild conditions in the absence of any catalysts, additives, or oxidants. Various functional groups including as ester, amino, methoxy, bromo, trifluoromethyl, nitro and carbonyl are tolerated well in this transformation, and the corresponding γ‐keto sulfones are afforded in 35% to 95% yields. The proposed mechanism implies that this reaction proceeds through γ‐keto sulfinate intermediate generated in situ, which further undergoes nucleophilic substitution with alkyl halides leading to γ‐keto sulfones.

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NiCoFeP Nanofibers as an Efficient Electrocatalyst for Oxygen Evolution Reaction and Zinc–Air Batteries
Authors: Bian Juanjuan , Sun Chunwen
Published: April 2021

The development of high‐performance and low‐cost bifunctional electrocatalysts is still challenging for solving current energy and environmental problems. However, most electrocatalysts require complex synthesis processes, which prohibit mass production. Herein, NiCoFeP nanofibers are synthesized by phosphating the electrospun Ni,Co precursor nanofibers and subsequent displacement reaction of Ni and Fe3+ via impregnation of Fe(NO3)3 solution. The obtained NiCoFeP nanofibers catalyst possesses high intrinsic activity, abundant active sites, and superior kinetics, which shows excellent oxygen evolution reaction (OER) performance with low overpotential of 0.309 V at 50 mA cm−2 in 1 m KOH solution. It also exhibits a long‐term cycling performance for 200 h at 10 mA cm−2 as the cathode for zinc–air battery. Furthermore, it is demonstrated that this displacement reaction method is also suitable for preparing other catalysts NiMnP and NiCuP to enhance their OER performance. This work presents a novel approach for the fabrication of multimetallic catalysts for electrocatalysis.
A Study of [3+2] Cycloaddition Reaction of Hydrazonoyl Chloride and β‐Oxodithioester Under Lewis Acid Catalysis: Stereoselective Synthesis of (Z)‐1,3,4‐Thiadiazol‐2(3H)‐Ylidenes.
Authors: Chellu Ramesh Kumar , Kurva Srinivas , Soda Anil Kumar , Chilaka Sai Krishna , Nanubolu Jagadeesh Babu , Madabhushi Sridhar
Published: April 2021

Hydrazonoyl chlorides underwent unprecedented stereoselective [3+2] cycloaddition reaction with β‐oxodithioesters and β‐oxothioamides under Lewis acid catalysis producing (Z)‐1,3,4‐ thiadiazol‐2(3H)‐ylidenes in high yields. These products are obtained also with a base. Though same products are obtained in both these conditions, they involve different reaction mechanisms. In base mediated reactions, 1,3‐dipolar cycloaddition of a nitrilimine to C=S is operative and in Lewis acid catalysed reactions, β‐oxodithioester/β‐oxothioamide undergoes addition‐cyclization reactions with a hydrazonoyl chloride.
A Two‐Dimensional Polyimide‐Graphene Heterostructure with Ultra‐fast Interlayer Charge Transfer
Authors: Liu Kejun , Li Jiang , Qi Haoyuan , Hambsch Mike , Rawle Jonathan , Vázquez Adrián Romaní , Nia Ali Shaygan , Pashkin Alexej , Schneider Harald , Polozij Mirosllav , Heine Thomas , Helm Manfred , Mannsfeld Stefan C. B. , Kaiser Ute , Dong Renhao , Feng Xinliang
Published: April 2021

Two‐dimensional polymers (2DPs) are a class of atomically/molecularly thin crystalline organic 2D materials. They are intriguing candidates for the development of unprecedented organic–inorganic 2D van der Waals heterostructures (vdWHs) with exotic physicochemical properties. In this work, we demonstrate the on‐water surface synthesis of large‐area (cm2), monolayer 2D polyimide (2DPI) with 3.1‐nm lattice. Such 2DPI comprises metal‐free porphyrin and perylene units linked by imide bonds. We further achieve a scalable synthesis of 2DPI‐graphene (2DPI‐G) vdWHs via a face‐to‐face co‐assembly of graphene and 2DPI on the water surface. Remarkably, femtosecond transient absorption spectroscopy reveals an ultra‐fast interlayer charge transfer (ca. 60 fs) in the resultant 2DPI‐G vdWH upon protonation by acid, which is equivalent to that of the fastest reports among inorganic 2D vdWHs. Such large interlayer electronic coupling is ascribed to the interlayer cation–π interaction between 2DP and graphene.
A Polarity‐Sensitive Ratiometric Fluorescence Probe for Monitoring Changes in Lipid Droplets and Nucleus during Ferroptosis
Authors: Wang Kang‐Nan , Liu Liu‐Yi , Mao Duo , Xu Shidang , Tan Cai‐Ping , Cao Qian , Mao Zong‐Wan , Liu Bin
Published: April 2021

Ferroptosis regulates cell death through reactive oxygen species (ROS)‐associated lipid peroxide accumulation, which is expected to affect the structure and polarity of lipid droplets (LDs), but with no clear evidence. Herein, we report the first example of an LD/nucleus dual‐targeted ratiometric fluorescent probe, CQPP, for monitoring polarity changes in the cellular microenvironment. Due to the donor–acceptor structure of CQPP, it offers ratiometric fluorescence emission and fluorescence lifetime signals that reflect polarity variations. Using nucleus imaging as a reference, CQPP was applied to report the increase in LD polarity and the homogenization of polarity between LDs and cytoplasm in the ferroptosis model. This LD/nucleus dual‐targeted fluorescent probe shows the great potential of using fluorescence imaging to study ferroptosis and ferroptosis‐related diseases.
Using a simple method to prepare UiO‐66‐NH2/chitosan composite membranes for oil–water separation
Authors: Zhu Ximei , Yu Zongxue , Zeng Haojie , Feng Xiaofang , Liu Yuchuan , Cao Kunyao , Li Xuyang , Long Runxuan
Published: April 2021

Chitosan (CS) was used as a cross‐linking agent to modify UiO‐66‐NH2, and the modified UiO‐66‐NH2 was fixed on the mixed cellulose membrane (MCE) through vacuum filtration technology to prepare a new type of membrane. The membrane exhibited excellent hydrophilicity in the air and excellent super‐oleophobic performance underwater, and effectively separated various oil–water emulsions. When separating petroleum ether‐water emulsion, the filtration flux of the modified membrane was 2000 L m−2 h−1 higher than that of MCE, and the separation efficiency can reach more than 95%. After 10 cycles, the flux of the modified membrane was about four times of that MCE, which was 500 L m−2 h−1. Most importantly, the membrane still maintained underwater superoleophobicity in the environment of strong acid, strong base, and salt solution.
Metformin hydrochloride sustained release biopolymeric system composed by PLLA‐CMC microparticles
Authors: da Silva Thiago Schroeder , Silva Denise Abatti Kasper , Nogueira André Lourenço
Published: April 2021

Metformin hydrochloride (MetHCl) is a drug extensively used to treat diabetes mellitus Type 2. However, its high hydrophilicity drastically reduces its metabolic absorption. Consequently, high drug concentrations should be taken by patients to achieve the desired therapeutical efficiency, causing several side effects. The present study proposes the development of a MetHCl sustained release biopolymeric system composed of poly(l‐lactic acid) (PLLA) and carboxymethyl cellulose (CMC) as a strategy to minimize the problems aforementioned. The PLLA‐CMC microparticles were produced by the double emulsion‐solvent evaporation technique using two distinct emulsifiers in the first emulsion (Span 80 and Tween 80). The microparticles were characterized by ultraviolet–visible spectrophotometry, scanning electron microscopy with field emission gun, thermogravimetric analyses, and differential scanning calorimetry (DSC). Additionally, in vitro drug release assays were performed. The results demonstrated that the emulsion stability and encapsulation efficiency increased in a dependent fashion way with the CMC concentration. DSC findings showed that the choice of the emulsifier of the first emulsion influences the polymer particle's crystallinity and, consequently, the releasing behavior of the drug. The in vitro studies revealed that the encapsulation of MetHCl in PLLA‐CMC microparticles is a promising sustained release system compatible with a zero‐order kinetic mechanism.
Biocidal efficacy of tutin and its influence on immune cells and expression of growth‐blocking and neuroglian peptides in Mythimna separata (Lepidoptera: Noctuidae)
Authors: Li Feifei , Cui Jun , Shaheen Tayyab , Tang Guanghui , Wang Tao , Woolfley Tracy , Li Menglou
Published: April 2021

Mythimna separata Walker (Lepidoptera: Noctuidae) is one of the major pests that can cause severe damage to grain crops. The development of low‐toxicity and high‐performance botanical insecticides is becoming the focus of new pesticide research to control M. separata. Tutin, a sesquiterpene lactone compound obtained from Coriaria sinica Maxim, a native Chinese poisonous plant, has antifeedant, absorption, and stomach poisoning against a variety of pests. To understand the toxic effect of tutin on M. separata larvae, we set out to determine their antifeedant, mortality, paralysis, weight change, and to examine the spreading of M. separata hemocytes under different concentrations of tutin treatment. Tissue distribution of the immune‐associated gene growth‐blocking peptide (GBP) and neuroglian peptide (Nrg) was detected by reverse transcription polymerase chain reaction (PCR). Furthermore, real‐time quantitative PCR was carried out to determine the expression profiles of GBP and Nrg after different concentrations of tutin stimulation. Our results revealed that tutin exhibited significant antifeedant and insecticidal activities, paralysis, weight loss to M. separata. Besides, tutin significantly influenced on the morphology of hemocytes and enhanced the expression of GBP and Nrg in M. separata.
Three‐Phase Reconstruction Reveals How the Microscopic Structure of the Carbon‐Binder Domain Affects Ion Transport in Lithium‐Ion Batteries
Authors: Kroll Moritz , Karstens Sarah L. , Cronau Marvin , Höltzel Alexandra , Schlabach Sabine , Nobel Nikita , Redenbach Claudia , Roling Bernhard , Tallarek Ulrich
Published: April 2021

The morphology of the electrolyte‐filled pore space in lithium‐ion batteries is determined by the solid microstructure formed by μm‐sized active material particles and the smaller‐featured carbon binder domain (CBD). Tomographic reconstructions have largely neglected the CBD, resulting in inadequately defined pore space morphologies at odds with experimental ionic tortuosity values. We present a three‐phase reconstruction of a LiCoO2 composite cathode by focused ion‐beam scanning electron microscopy tomography. Morphological analysis proves that the reconstruction, which combines an unprecedented volume (20 μm minimum edge length) with the hitherto highest resolution (13.9×13.9×20 nm3 voxel size), represents the cathode's pore space morphology. Pore‐scale diffusion simulations show consideration of the resolved CBD as indispensable to reproduce ionic tortuosity values from electrochemical impedance spectroscopy. Our results reveal the CBD as a convoluted network that dominates the pore space morphology and limits Li+ transport through tortuous and constricted diffusion pathways.
Further evaluation of contingencies on lying about homework completion
Authors: Stocco Corey S. , Moline Adam D. , Bowar Stephanie
Published: April 2021

Lying during childhood can have a negative impact on the quality of relationships between caregivers and children. Although caregivers have identified lying as a major concern, few studies have evaluated the conditions under which lying about socially significant events is more or less probable. This study extended Sauter et al. (2020) in two ways. First, we assessed the extent to which modified baseline procedures reliably evoked lies about homework completion or academic dishonesty. Second, we evaluated the effects of an intervention package comprised of praise‐based components recommended by professionals and supported by previous research. When the praise‐based intervention was ineffective, we implemented a tangible intervention comprised of rules, and differential reinforcement. All participants lied about academic dishonesty under baseline conditions and continued to do so when researchers implemented the praise‐based intervention. In contrast, the tangible intervention increased honest reports for all participants and decreased academic dishonesty for two of three participants. These effects were replicated in probe sessions conducted by one participant's mother.
IL‐10 lentivirus‐laden hydrogel tubes increase spinal progenitor survival and neuronal differentiation after spinal cord injury
Authors: Ciciriello Andrew J. , Smith Dominique R. , Munsell Mary K. , Boyd Sydney J. , Shea Lonnie D. , Dumont Courtney M.
Published: April 2021

A complex cellular cascade characterizes the pathophysiological response following spinal cord injury (SCI) limiting regeneration. Biomaterial and stem cell combination therapies together have shown synergistic effects, compared to the independent benefits of each intervention, and represent a promising approach towards regaining function after injury. In this study, we combine our polyethylene glycol (PEG) cell delivery platform with lentiviral‐mediated overexpression of the anti‐inflammatory cytokine interleukin (IL)−10 to improve mouse embryonic Day 14 (E14) spinal progenitor transplant survival. Immediately following injury in a mouse SCI hemisection model, five PEG tubes were implanted followed by direct injection into the tubes of lentivirus encoding for IL‐10. Two weeks after tube implantation, mouse E14 spinal progenitors were injected directly into the integrated tubes, which served as a soft substrate for cell transplantation. Together, the tubes with the IL‐10 encoding lentivirus improved E14 spinal progenitor survival, assessed at 2 weeks posttransplantation (4 weeks postinjury). On average, 8.1% of E14 spinal progenitors survived in mice receiving IL‐10 lentivirus‐laden tubes compared with 0.7% in mice receiving transplants without tubes, an 11.5‐fold difference. Surviving E14 spinal progenitors gave rise to neurons when injected into tubes. Axon elongation and remyelination were observed, in addition to a significant increase in functional recovery in mice receiving IL‐10 lentivirus‐laden tubes with E14 spinal progenitor delivery compared to the injury only control by 4 weeks postinjury. All other conditions did not exhibit increased stepping until 8 or 12 weeks postinjury. This system affords increased control over the transplantation microenvironment, offering the potential to improve stem cell‐mediated tissue regeneration.
A configurable evaluation system for PLC experiments deployed on cloud
Authors: Zhang Shirong , Tang Yuling
Published: April 2021

Programmable logic controller (PLC) is always set as a professional course of automation‐related majors in Chinese universities and colleges. Abundant experiments are required to ensure that the students are sufficiently trained to get qualified practical skills and engineering abilities. The evaluation of abundant PLC experiments is a heavy and time‐consuming task, and it is hard to grade an experiment result precisely and fairly. In this paper, a cloud‐based automatic evaluation system for PLC experiments is accordingly proposed to deal with the above problems. Aliyun is employed to build the system platform. During experiments, client threads on the cloud will be scheduled to accesses the on‐site S7‐1500 PLCs through OLE for process control (OPC) UA protocol. Further, an innovative section‐based experiment management method is proposed to make the system open, configurable, and thus extendable. The system relieves the hard work of the teachers on experiment evaluation and provides accurate evaluation conclusions. In contrast, the students can get more comprehensive feedback information and advice from the system to better understand the experiments and the behind principles. The cloud‐based framework, the standard protocol as OPC UA, and the configurability of the system can be good references for other relevant systems.
Germacrone improves liver fibrosis by regulating the PI3K/AKT/mTOR signalling pathway
Authors: Ji De , Zhao Qi , Qin Yuwen , Tong Huangjin , Wang Qiaohan , Yu Mengting , Mao Chunqin , Lu Tulin , Qiu Jinchun , Jiang Chengxi
Published: April 2021

Liver fibrosis is a primary threat to public health, owing to limited therapeutic options. Germacrone (GM) has been shown to exert various curative effects against human diseases, including liver injury. The aim of this study was to investigate the pharmacological effects of GM in the pathophysiology of hepatic fibrosis and determine its potential mechanisms of action. A liver fibrosis rat model was established via carbon tetrachloride (CCl4) treatment, and LX‐2 cells were stimulated with TGF‐β1. The effects of GM on liver fibrosis and its relationship with the phosphatidylinositol 3‐kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signalling pathway were investigated. In the CCl4 fibrosis‐induced rat model, GM improved histological damage, inhibited the activity of hepatic α‐smooth muscle actin and improved serum alanine aminotransferase and aspartate aminotransferase levels in a dose‐dependent manner. GM potently inhibited hepatic stellate cells (HSCs) growth and epithelial–mesenchymal transition (EMT) progression, as reflected by the altered expression of proliferative (Ki‐67, PCNA and cleaved caspase‐3) and EMT‐related (E‐cadherin and vimentin) proteins. In TGF‐β1‐stimulated LX‐2 cells, GM significantly inhibited the survival and activation of HSCs and induced cell apoptosis. GM also suppressed the migration ability and reversed the EMT process in HSCs. Following GM treatment, the phosphorylation of the PI3K, AKT and mTOR proteins was reduced in the liver of CCl4‐treated rats and TGF‐β1‐stimulated LX‐2 cells, indicating that GM may attenuate hepatic fibrosis via the PI3K/AKT/mTOR signalling pathway. These outcomes highlight the anti‐fibrotic effects of GM and suggest that it is a potential therapeutic agent for the treatment of liver fibrosis.
Urticarial vasculitis: A Complication of SMZ‐TMP therapy
Authors: Bhasin Arveen K. , Sluzevich Jason C.
Published: April 2021

Recognize that delayed hypersensitivity reactions to sulfonamides may present as urticated plaques with hyperpigmentation and purpura for which a diagnosis of urticarial vasculitis should be considered.