bluuebunny/crossref_metadata_2025 huggingface dataset:
A gradient of Wnt activity positions the neurosensory domains of the inner ear
Authors: Żak Magdalena , Daudet Nicolas
Published: March 2021

The auditory and vestibular organs of the inner ear and the neurons that innervate them originate from Sox2-positive and Notch-active neurosensory domains specified at early stages of otic development. Sox2 is initially present throughout the otic placode and otocyst, and then it becomes progressively restricted to a ventro-medial domain. Using gain- and loss-of-function approaches in the chicken otocyst, we show that these early changes in Sox2 expression are regulated in a dose-dependent manner by Wnt/beta-catenin signalling. Both high and very low levels of Wnt activity repress Sox2 and neurosensory competence. However, intermediate levels allow the maintenance of Sox2 expression and sensory organ formation. We propose that a dorso-ventral (high-to-low) gradient and wave of Wnt activity initiated at the dorsal rim of the otic placode progressively restricts Sox2 and Notch activity to the ventral half of the otocyst, thereby positioning the neurosensory competent domains in the inner ear.
Decoding the physical principles of two-component biomolecular phase separation
Authors: Zhang Yaojun , Xu Bin , Weiner Benjamin G , Meir Yigal , Wingreen Ned S
Published: March 2021

Cells possess a multiplicity of non-membrane-bound compartments, which form via liquid-liquid phase separation. These condensates assemble and dissolve as needed to enable central cellular functions. One important class of condensates is those composed of two associating polymer species that form one-to-one specific bonds. What are the physical principles that underlie phase separation in such systems? To address this question, we employed coarse-grained molecular dynamics simulations to examine how the phase boundaries depend on polymer valence, stoichiometry, and binding strength. We discovered a striking phenomenon – for sufficiently strong binding, phase separation is suppressed at rational polymer stoichiometries, which we termed the magic-ratio effect. We further developed an analytical dimer-gel theory that confirmed the magic-ratio effect and disentangled the individual roles of polymer properties in shaping the phase diagram. Our work provides new insights into the factors controlling the phase diagrams of biomolecular condensates, with implications for natural and synthetic systems.
Longitudinal proteomic profiling of dialysis patients with COVID-19 reveals markers of severity and predictors of death
Authors: Gisby Jack , Clarke Candice L , Medjeral-Thomas Nicholas , Malik Talat H , Papadaki Artemis , Mortimer Paige M , Buang Norzawani B , Lewis Shanice , Pereira Marie , Toulza Frederic , Fagnano Ester , Mawhin Marie-Anne , Dutton Emma E , Tapeng Lunnathaya , Richard Arianne C , Kirk Paul DW , Behmoaras Jacques , Sandhu Eleanor , McAdoo Stephen P , Prendecki Maria F , Pickering Matthew C , Botto Marina , Willicombe Michelle , Thomas David C , Peters James E
Published: March 2021

End-stage kidney disease (ESKD) patients are at high risk of severe COVID-19. We measured 436 circulating proteins in serial blood samples from hospitalised and non-hospitalised ESKD patients with COVID-19 (n = 256 samples from 55 patients). Comparison to 51 non-infected patients revealed 221 differentially expressed proteins, with consistent results in a separate subcohort of 46 COVID-19 patients. Two hundred and three proteins were associated with clinical severity, including IL6, markers of monocyte recruitment (e.g. CCL2, CCL7), neutrophil activation (e.g. proteinase-3), and epithelial injury (e.g. KRT19). Machine-learning identified predictors of severity including IL18BP, CTSD, GDF15, and KRT19. Survival analysis with joint models revealed 69 predictors of death. Longitudinal modelling with linear mixed models uncovered 32 proteins displaying different temporal profiles in severe versus non-severe disease, including integrins and adhesion molecules. These data implicate epithelial damage, innate immune activation, and leucocyte–endothelial interactions in the pathology of severe COVID-19 and provide a resource for identifying drug targets.
Reformulation of an extant ATPase active site to mimic ancestral GTPase activity reveals a nucleotide base requirement for function
Authors: Updegrove Taylor B , Harke Jailynn , Anantharaman Vivek , Yang Jin , Gopalan Nikhil , Wu Di , Piszczek Grzegorz , Stevenson David M , Amador-Noguez Daniel , Wang Jue D , Aravind L , Ramamurthi Kumaran S
Published: March 2021

Hydrolysis of nucleoside triphosphates releases similar amounts of energy. However, ATP hydrolysis is typically used for energy-intensive reactions, whereas GTP hydrolysis typically functions as a switch. SpoIVA is a bacterial cytoskeletal protein that hydrolyzes ATP to polymerize irreversibly duringBacillus subtilissporulation. SpoIVA evolved from a TRAFAC class of P-loop GTPases, but the evolutionary pressure that drove this change in nucleotide specificity is unclear. We therefore reengineered the nucleotide-binding pocket of SpoIVA to mimic its ancestral GTPase activity. SpoIVAGTPasefunctioned properly as a GTPase but failed to polymerize because it did not form an NDP-bound intermediate that we report is required for polymerization. Further, incubation of SpoIVAGTPasewith limiting ATP did not promote efficient polymerization. This approach revealed that the nucleotide base, in addition to the energy released from hydrolysis, can be critical in specific biological functions. We also present data suggesting that increased levels of ATP relative to GTP at the end of sporulation was the evolutionary pressure that drove the change in nucleotide preference in SpoIVA.
FNG-IE: an improved graph-based method for keyword extraction from scholarly big-data
Authors: Tahir Noman , Asif Muhammad , Ahmad Shahbaz , Malik Muhammad Sheraz Arshad , Aljuaid Hanan , Butt Muhammad Arif , Rehman Mobashar
Published: March 2021

Keyword extraction is essential in determining influenced keywords from huge documents as the research repositories are becoming massive in volume day by day. The research community is drowning in data and starving for information. The keywords are the words that describe the theme of the whole document in a precise way by consisting of just a few words. Furthermore, many state-of-the-art approaches are available for keyword extraction from a huge collection of documents and are classified into three types, the statistical approaches, machine learning, and graph-based methods. The machine learning approaches require a large training dataset that needs to be developed manually by domain experts, which sometimes is difficult to produce while determining influenced keywords. However, this research focused on enhancing state-of-the-art graph-based methods to extract keywords when the training dataset is unavailable. This research first converted the handcrafted dataset, collected from impact factor journals into n-grams combinations, ranging from unigram to pentagram and also enhanced traditional graph-based approaches. The experiment was conducted on a handcrafted dataset, and all methods were applied on it. Domain experts performed the user study to evaluate the results. The results were observed from every method and were evaluated with the user study using precision, recall and f-measure as evaluation matrices. The results showed that the proposed method (FNG-IE) performed well and scored near the machine learning approaches score.
LSTM-based sentiment analysis for stock price forecast
Authors: Ko Ching-Ru , Chang Hsien-Tsung
Published: March 2021

Investing in stocks is an important tool for modern people’s financial management, and how to forecast stock prices has become an important issue. In recent years, deep learning methods have successfully solved many forecast problems. In this paper, we utilized multiple factors for the stock price forecast. The news articles and PTT forum discussions are taken as the fundamental analysis, and the stock historical transaction information is treated as technical analysis. The state-of-the-art natural language processing tool BERT are used to recognize the sentiments of text, and the long short term memory neural network (LSTM), which is good at analyzing time series data, is applied to forecast the stock price with stock historical transaction information and text sentiments. According to experimental results using our proposed models, the average root mean square error (RMSE ) has 12.05 accuracy improvement.
Contextual dimensions for cache replacement schemes in information-centric networks: a systematic review
Authors: Pires Stéfani , Ziviani Artur , Sampaio Leobino N.
Published: March 2021

In recent years, information-centric networks (ICNs) have gained attention from the research and industry communities as an efficient and reliable content distribution network paradigm, especially to address content-centric and bandwidth-needed applications together with the heterogeneous requirements of emergent networks, such as the Internet of Things (IoT), Vehicular Ad-hoc NETwork (VANET) and Mobile Edge Computing (MEC). In-network caching is an essential part of ICN architecture design, and the performance of the overall network relies on caching policy efficiency. Therefore, a large number of cache replacement strategies have been proposed to suit the needs of different networks. The literature extensively presents studies on the performance of the replacement schemes in different contexts. The evaluations may present different variations of context characteristics leading to different impacts on the performance of the policies or different results of most suitable policies. Conversely, there is a lack of research efforts to understand how the context characteristics influence policy performance. In this direction, we conducted an extensive study of the ICN literature through a Systematic Literature Review (SLR) process to map reported evidence of different aspects of context regarding the cache replacement schemes. Our main findings contribute to the understanding of what is a context from the perspective of cache replacement policies and the context characteristics that influence cache behavior. We also provide a helpful classification of policies based on context dimensions used to determine the relevance of contents. Further, we contribute with a set of cache-enabled networks and their respective context characteristics that enhance the cache eviction process.
Effects of temperature frequency trends on projected japonica rice (Oryza sativaL.) yield and dry matter distribution with elevated carbon dioxide
Authors: Zhou Zeyu , Jin Jiming , Song Libing , Yan Ling
Published: March 2021

In this study, we investigated the effects of temperature frequency trends on the projected yield and dry matter distribution of japonica rice (Oryza sativaL.) with elevated carbon dioxide (CO2) under future climate change scenarios in northwestern China. The Crop Environment Resource Synthesis (CERES)-Rice model was forced with the outputs from three general circulation models (GCMs) to project the rice growth and yield. Future temperature trends had the most significant impact on rice growth, and the frequency of higher than optimal temperatures (∼24–28oC) for rice growth showed a marked increase in the future, which greatly restricted photosynthesis. The frequency of extreme temperatures (>35oC) also increased, exerting a strong impact on rice fertilization and producing a significantly reduced yield. Although the increased temperature suppressed photosynthetic production, the elevated CO2stimulated this production; therefore, the net result was determined by the dominant process. The aboveground biomass at harvest trended downward when temperature became the major factor in photosynthetic production and trended upward when CO2-fertilization dominated the process. The trends for the leaf and stem dry matter at harvest were affected not only by changes in photosynthesis but also by the dry matter distribution to the panicles. The trends for the rice panicle dry matter at harvest were closely related to the effects of temperature and CO2on photosynthetic production, and extreme temperatures also remarkably affected these trends by reducing the number of fertilized spikelets. The trends of rice yield were very similar to those of panicle dry matter because the panicle dry matter is mostly composed of grain weight (yield). This study provides a better understanding of the japonica rice processes, particularly under extreme climate scenarios, which will likely become more frequent in the future.
pmparser and PMDB: resources for large-scale, open studies of the biomedical literature
Authors: Schoenbachler Joshua L. , Hughey Jacob J.
Published: March 2021

PubMed is an invaluable resource for the biomedical community. Although PubMed is freely available, the existing API is not designed for large-scale analyses and the XML structure of the underlying data is inconvenient for complex queries. We developed an R package called pmparser to convert the data in PubMed to a relational database. Our implementation of the database, called PMDB, currently contains data on over 31 million PubMed Identifiers (PMIDs) and is updated regularly. Together, pmparser and PMDB can enable large-scale, reproducible, and transparent analyses of the biomedical literature. pmparser is licensed under GPL-2 and available at https://pmparser.hugheylab.org. PMDB is available in both PostgreSQL (DOI 10.5281/zenodo.4008109) and Google BigQuery (https://console.cloud.google.com/bigquery?project=pmdb-bq&d=pmdb).
The association between prior physical fitness and depression in young adults during the COVID-19 pandemic—a cross-sectional, retrospective study
Authors: Dun Yaoshan , Ripley-Gonzalez Jeffrey W. , Zhou Nanjiang , Li Qiuxia , Chen Meijuan , Hu Zihang , Zhang Wenliang , Thomas Randal J. , Olson Thomas P. , Liu Jie , Dong Yuchen , Liu Suixin
Published: March 2021

Background

The COVID-19 pandemic has led to a spike in deleterious mental health. This dual-center retrospective cross-sectional study assessed the prevalence of depression in young adults during this pandemic and explored its association with various physical fitness measures.

Methods

This study enrolled 12,889 (80% female) young adults (mean age 20 ± 1) who performed a National Student Physical Fitness battery from December 1st, 2019, to January 20th, 2020, and completed a questionnaire including Beck’s Depression Inventory in May 2020. Independent associations between prior physical fitness and depression during the pandemic were assessed using multivariable linear and binary logistic regressions accordingly, covariates including age, dwelling location, economic level, smoking, alcohol, living status, weight change, and exercise volume during the pandemic. Sex- and baseline stress-stratified analyses were performed.

Results

Of the study population 13.9% of men and 15.0% of women sampled qualified for a diagnosis of depression. After multivariable adjustment, anaerobic (mean change 95% CI −3.3 [−4.8 to 1.8]) aerobic (−1.5 [−2.64 to −0.5]), explosive (−1.64 [−2.7 to −0.6]) and muscular (−1.7 [−3.0 to −0.5]) fitness were independently and inversely associated with depression for the overall population. These remained consistent after sex- and baseline stress-stratification. In binary logistic regression, the combined participants with moderate, high or excellent fitness also showed a much lower risk compared to those least fit in anaerobic (odd ratio (OR) 95% CI 0.68 [0.55–0.82]), aerobic (0.80 [0.68–0.91]), explosive (0.72 [0.61–0.82]), and muscular (0.66 [0.57–0.75]) fitness.

Conclusions

These findings suggest that prior physical fitness may be inversely associated with depression in young adults during a pandemic.
Nephroprotective Impact of Adjuvant Yoga Therapy on Diabetes- A Randomised Controlled Trial
Authors: Balaji Rajasekar , Ramanathan Meena , Bhavanani Ananda Balayogi
Published: March 2021

Introduction: Recent studies have provided abundant evidence about benefits of yoga in various chronic disorders. Diabetes Mellitus (DM) is a group of metabolic diseases characterised by chronic hyperglycaemia and renal complications of the disease are especially notable. It is estimated that 10% to 40% cases of Type 2 DM (T2DM) eventually end up having kidney failure. Yoga therapy may help to prevent progression of kidney damage in diabetic patients. Aim: To evaluate the effect of adjuvant yoga therapy on renal profile in diabetic patients. Materials and Methods: This single blind Randomised Controlled Trial (RCT) was designed as an interdisciplinary collaborative work between Centre for Yoga Therapy, Education and Research (CYTER) and Department of Endocrinology of Mahatma Gandhi Medical College and Research Institute, Sri Balaji Vidyapeeth, Puducherry, India. A total of 72 diabetic patients with HbA1c, more than 7% were recruited and pre study evaluation of Fasting Blood Sugar (FBS), Postprandial Blood Sugar (PPBS), HbA1c, blood urea and serum creatinine were done. They were then randomised into control group (n=36) who received only standard medical management and yoga group (n=36) who received yoga therapy thrice weekly for 4 months along with standard medical management. Poststudy evaluation of all parameters was done at end of study period and data were analysed by Student’s paired and unpaired t-test for intra and intergroup comparisons. Results: Postinterventional comparisons revealed statistically significant reductions (p<0.001) in all glycaemic and renal parameters in the group receiving yoga therapy when compared with control group who didn’t receive the yoga intervention. Intragroup comparisons revealed significant reduction of all parameters in yoga group. Conclusion: It is concluded from the present RCT that yoga has a definite role as an adjuvant therapy as it enhances standard medical care and hence, can be recommended in routine clinical management of diabetes to prevent progression into complications that are part of the natural history of the disease.
Effect of COVID-19 on Mental Health of Teenagers
Authors: Rawat Mahika , Sehrawat Anuradha
Published: March 2021

The “Type of Article” of this paper is “Letter to the Editor”. This paper discuses about: “Effect of COVID-19 on Mental Health of Teenagers”. No formal abstract is available. Readers are requested to read the full article.
Impact of Climate Change on Worlds Economy and Hydrological System
Authors: Ali Sajid , Jan Inayatullah
Published: March 2021

The Mediterranean region appears to be particularly responsive to global and climate change. The global mean temperature has increased by 0.8°C compared with preindustrial levels while Europe has warmed more than the global average, especially in the Mediterranean, the north-east region, and mountain areas. Increasingly drier conditions are observed in the Mediterranean region both in the wet and in the dry season (~20%) with an increasingly irregular precipitation in both seasons (~ 40% in the dry season). The annual river flows have also decreased in the Mediterranean region, a difference projected to exacerbate due to climate and global change, which made the Mediterranean region most prone to an increase in drought hazard and water stress. Iberian Peninsula has been already affected by several major droughts, e.g. the recent one in 2005. These driving forces of global change impacts on water availability, water quality, and ecosystem services in Mediterranean river basins of the Iberian Peninsula, as well as their impacts on the human society and economy, makes it an important issue on the EU agenda. This thesis is an approach to quantify and analyze the water quantity, hydrological ecosystem services, and water supply in temperate regions under environmental changes. A hydrological model is developed for a low flow Mediterranean river (Francolí River) to assess the water allocation situation in the river basin using MIKE BASIN. Since the Mediterranean regions are hard hit by the changes in the global climatic patterns, the hydrological model focuses on the water distribution system & flow in the region.
Comparison of Axial Length Measurements with the Use of Optical Biometry (IOL Master 700) and Ultrasound Biometry (A‐scan 550 Sonomed)
Authors: Pateras E. , Karadimou D.
Published: March 2021

Purpose: To compare measurements of axial length obtained with A-scan and IOL Master. The study was design to collect the axial length values resulting from the application of both methods on the same eye (R.E.) and then to compare them.

Methodology Place and Duration of Study: 50 healthy patients selected randomly after visiting the clinic for daily routine examination. at the general hospital of Athens “Korgialenio – Benakio” were invited to participate in the study. The study took place in collaboration of University of West Attica Dept Biomedical Science Course Optics & Optometry with the general hospital of Athens “Korgialenio – Benakio”. Axial length measurements were obtained both by contact ultrasound (A‐scan 550 Sonomed, Lake Success, NY, USA) and by non‐contact laser interferometry (IOL Master 700 SWEPT Source Biometry). Two sets of measurements were repeated by a single examiner for each method.

Results: A total of 50 eyes in 50 patients were evaluated. All participants volunteer to participate in this study. Estimates of axial length obtained with the two techniques were highly correlated. Axial lengths obtained with the contact method (mean 24.23mm, SD 1.64mm) were lower than those obtained with the non‐contact method (mean 23.29mm, SD 1.59mm) and the difference was not statistically significant (p = 0.150). The coefficient of variation was lower with non‐contact laser interferometry (6.58%) than with the ultrasound technique (6.76%).

Conclusion: Similar estimates of axial length are obtained using contact and non‐contact techniques, with the latter producing higher measurements results than the former. The A-scan and the non‐contact laser interferometry device (IOL Master 700) provide both reproducible results with similar the accuracy of measurements of axial length in the clinical setting.
Screening of Methanolic Extract for Antimicrobial Activity of Hyphaene thebaica L. Fruit Pulp from Sudanese Folklore
Authors: Abdallah Emad M.
Published: March 2021

Aim: To evaluate the antimicrobial potential of the methanolic extract of the fruit pulp of Hyphaene thebaica (Doum), a famous natural product in Sudan.

Methods: Agar-well diffusion test and minimum inhibition diffusion test (MIC).

Results: The investigation revealed that the extract showed no antifungal effect against Aspergillus niger ATCC 6275 and Candida albicans ATCC 10231. While it exhibited remarkable antibacterial activity against Staphylococcus aureus ATCC BAA 1026 and Pseudomonas aeruginosa ATCC 10145. Whereas, weak antibacterial activity was recorded with Bacillus cereus ATCC 10876 and Escherichia coli ATCC 1637.

Conclusion: The fruit pulp of Hyphaene thebaica (Doum) has good antibacterial activity against some Gram-positive and Gram-negative bacteria. Accordingly, the consumption of this fruit would exert several beneficial effects by virtue of its antibacterial activity, and further studies using different bacterial strains and clinical pathogens are recommended.
Solidariedade e Resistência LGBTQ+: análise da obra “Ética Marica”, de Paco Vidarte
Authors: Silveira Matheus Dos Santos da
Published: March 2021

O presente ensaio apresenta uma análise sobre a obra Ética Marica, último livro escrito pelo autor espanhol Paco Vidarte, identificando os mecanismos de solidariedade e resistência LGBTQ+ . Suas contribuições são fundamentais para problematizar as violências e encontrar formas de resistências. Entende-se que pessoas pertencentes à comunidade LGBTQ+ encontram diversas resistências, opressões, dentro de um conjunto maior de tensionamentos existentes na sociedade internacional ocidental contemporânea, na qual, diversas lógicas de repressão se fazem presentes e em constante replicação. Estratégias foram e são pensadas a fim de reforçar a luta por direitos, experiências, pelo ser LGBTQ+. A academia, nesse sentido, tem, dentre outros papéis, conferido voz a estes discursos silenciados, propulsionando debates que possam transformar, de alguma forma, a realidade como ela é. Vidarte foi um dos porta-vozes dessa perspectiva, ao, em suas obras, problematizar os sistemas opressores existentes na sociedade, não apenas espanhola, sendo reconhecido como um dos primeiros a inserir os estudos queer na academia. Enquanto pontos principais encontrados na obra, a solidariedade não apenas entre a comunidade LGBTQ+ mas entre todos aqueles que sofrem algum tipo de opressão, é necessária para o fortalecimento da resistência frente às estruturas de intolerância existentes. Para Vidarte, seria a partir da construção de uma solidariedade antissistema, que se preocupasse com o humano, que seria possível o desenvolvimento de uma ética marica. A análise literária, dessa forma, pode contribuir para a maior compreensão de temas como o do ativismo LGBTQ+ em suas mais variadas vertentes.
“A luta continua, companheiros... mas não para todos”: o esvaziamento das pautas LGBT no Sindicato de Trabalhadores em Educação da Universidade Federal do Rio de Janeiro
Authors: Santos Vieira de Jesus Diego , De Oliveira Santos Vieira de Jesus Henrique
Published: March 2021

O objetivo é examinar o esvaziamento das discussões sobre direitos civis e trabalhistas LGBT no Sindicato dos Trabalhadores em Educação da Universidade Federal do Rio de Janeiro (SINTUFRJ). O argumento central aponta que o SINTUFRJ assumiu papel primordial na mobilização contra a precarização do trabalho dos técnico-administrativos em educação (TAEs) na UFRJ e nas demais universidades federais no Brasil. Entretanto, o engajamento do SINTUFRJ na transformação dos TAEs em sujeitos políticos e sociais não pressupôs a eliminação de padrões heteronormativos no estabelecimento de objetivos, estratégias e mecanismos de reivindicação sindicais, de forma a se enfraquecer a atuação do grupo de trabalho LGBT do SINTUFRJ e se reduzir o peso das temáticas LGBT nas propostas do sindicato.
Não serei interrompida: o processo de silenciamento feminino no espaço político brasileiro
Authors: Coelho Naiara , Volotão Amanda
Published: March 2021

O presente artigo tem por objetivo averiguar o processo de silenciamento das mulheres no ambiente político brasileiro, com base na proposição analítica de três planos fundamentais: a ausência ou baixa representação de minorias no espaço político; a negação sistemática de participação da voz feminina nos ambientes de debate;  e a interdição permanente de discursos contra-hegemônicos entoados por vozes subalternas. Para tanto, parte da premissa de que o cenário político brasileiro se apresenta como um espaço frutífero para se pensar a violência simbólica sofrida pelos sujeitos femininos, a partir da operacionalização de formas que resultam na invisibilização das mulheres. Além de trazer uma revisão bibliográfica sobre a participação de minorias na esfera política, atentando para as diferenças entre uma política de ideias e uma política de presença, o estudo discorre sobre a prática do manterrupting no meio governamental, destacando tanto as problemáticas em categorizá-lo como micromachismo, quanto a relevância do discurso como próprio objeto de disputa. Em um segundo momento, analisa o assassinato da vereadora Marielle Franco como a representação máxima de interdição de uma voz e, ainda, reflete sobre os efeitos dessa tentativa de silenciamento, considerando a reverberação das pautas defendidas por Franco.   
Expressões de Masculinidades de Homens Usuários do Aplicativo Grindr
Authors: Sousa Anderson Reis , Santos Junior Fernando Jorge Nascimento , Mota Tilson Nunes
Published: March 2021

Este estudo tem por objetivo desvelar as expressões de masculinidades manifestadas a partir do discurso de homens usuários do aplicativo Grindr. Trata-se de um estudo netnográfico, descritivo, qualitativo, realizado através do aplicativo de relacionamento gay Grindr. Os resultados revelam que as expressões das masculinidades apresentadas nos perfis dos usuários são demarcadas por constructos hegemônicos e contra hegemônicos. Além disso, constatamos a ocorrência de opressões, desigualdades e a disseminação do ódio que pode influenciar na manutenção de relações saudáveis estabelecidas através do aplicativo.
Usos da internet como meio de comunicação e fonte de informação por idosos // Uses of the internet as a communication medium and information source by elderly
Authors: Foletto Rafael , Fiepke Rejane Beatriz , Wilhelm Eduarda
Published: March 2021

O presente artigo consiste em um estudo que visa investigar as características de uso da internet por idosos do município de Frederico Westphalen, Rio Grande do Sul. Também buscamos compreender a forma com que esta tecnologia impacta no consumo de meios de comunicação por esse grupo, atravessada pelos processos de midiatização. A perspectiva teórica desta pesquisa está fundamentada no conceito de midiatização a partir das ideias de autores como Verón (1997, 2001), Fausto Neto (2006) e Sodré (2007), que discorrem acerca dos processos de inserção da mídia e do seu papel nos distintos contextos sociais. O viés metodológico se constitui a partir de questionário e entrevistas com sujeitos de grupos da terceira idade do município.
Partial Coated Stem Cells with Bioinspired Silica as New Generation of Cellular Hybrid Materials
Authors: Maciel Marta M. , Correia Tiago R. , Gaspar Vítor M. , Rodrigues João M. M. , Choi Insung S. , Mano João F.
Published: March 2021

The manipulation of cell surfaces in anchorage‐dependent cells can help overcome difficulties presented during cell handling and application. Silica‐based protective mechanisms existing in free‐floating microorganisms may be used as inspiration for sustaining human cell survival in suspension. Gathering on this, herein human adipose‐derived mesenchymal stem cells (hASCs) are partially coated with a hard silica layer that operates as a supporting platform for individual cells in suspension. Inspired by the organic templates involved in biosilicification, a novel chitosan (CHT) derivative displaying fully natural quaternary amine moieties is synthetized via a rapid, one‐pot strategy. Silicification is promoted on individual hASCs surfaces via a two‐step process: a priming step onto previously adhered cell with this CHT derivative, followed by a biocompatible sol–gel process. hASCs holding a silica backpack exhibit enhanced cell survival in suspension conditions and can spread and acquire a more adherent phenotype. This new protocol for cell‐surface modification also provides a new generation of hybrid materials with functionalization of the silica backpack, which can be applied to different areas such as tissue engineering, biosensing, drug delivery, and targeted cell‐based therapies.
Highly Efficient and Rapid Inactivation of Coronavirus on Non‐Metal Hydrophobic Laser‐Induced Graphene in Mild Conditions
Authors: Huang Libei , Gu Meijia , Wang Zhaoyu , Tang Tsz Wing , Zhu Zonglong , Yuan Yuncong , Wang Dong , Shen Chao , Tang Ben Zhong , Ye Ruquan
Published: March 2021

The prevalence of COVID‐19 has caused global dysfunction in terms of public health, sustainability, and socio‐economy. While vaccination shows potential in containing the spread, the development of surfaces that effectively reduces virus transmission and infectivity is also imperative, especially amid the early stage of the pandemic. However, most virucidal surfaces are operated under harsh conditions, making them impractical or potentially unsafe for long‐term use. Here, it is reported that laser‐induced graphene (LIG) without any metal additives shows marvelous antiviral capacities for coronavirus. Under low solar irradiation, the virucidal efficacy of the hydrophobic LIG (HLIG) against HCoV‐OC43 and HCoV‐229E can achieve 97.5% and 95%, respectively. The photothermal effect and the hydrophobicity of the HLIG synergistically contribute to the superior inactivation capacity. The stable antiviral performance of HLIG enables its multiple uses, showing advantages in energy saving and environmental protection. This work discloses a potential method for antiviral applications and has implications for the future development of antiviral materials.
Synchronous Promotion in Sodiophilicity and Conductivity of Flexible Host via Vertical Graphene Cultivator for Longevous Sodium Metal Batteries
Authors: Lu Chen , Gao Zhixiao , Liu Bingzhi , Shi Zixiong , Yi Yuyang , Zhao Wen , Guo Wenyue , Liu Zhongfan , Sun Jingyu
Published: March 2021

Sodium (Na) metal batteries are nowadays appealing due to high specific capacity and low cost. However, major caveats including severe Na dendrite growth, unstable solid electrolyte interphase formation, and poor mechanical robustness have hampered its practicability. In this report, a highly sodiophilic and conductive host harnessing hierarchical vertical graphene (VG) cultivator and Co nanoparticle/N‐doped carbon decorator (Co‐VG/CC) is designed to accommodate Na metal throughout a facile infusion route. The strong interaction between Co‐VG/CC and Na is realized by sodiophilic Co nanoparticle/N‐doped carbon hybrid, resulting in excellent structural stability of the electrode. The well‐regulated Na adsorption behavior and uniform stripping/plating mechanism is systematically investigated via theoretical simulation in harmonization with in situ/ex situ electroanalytical analysis. In consequence, as‐derived Na@Co‐VG/CC electrode effectively inhibits the dendrite formation, resulting in promising electrochemical performances in symmetric cell configuration (functioning at an elevated rate of 5.0 mA cm−2 under 5.0 mAh cm−2 for 280 h, delivering a high capacity of 6.0 mAh cm−2 at 3.0 mA cm−2 for 1000 h and maintaining an ultralong lifespan up to 2000 h). Meanwhile, assembled flexible Na metal battery full cell can sustain to work for 120 h, representing a great advance in practical energy storage applications.
Hemagglutinin Functionalized Liposomal Vaccines Enhance Germinal Center and Follicular Helper T Cell Immunity
Authors: Vu Mai N. , Kelly Hannah G. , Tan Hyon‐Xhi , Juno Jennifer A. , Esterbauer Robyn , Davis Thomas P. , Truong Nghia P. , Wheatley Adam K. , Kent Stephen J.
Published: March 2021

Despite remarkable successes of immunization in protecting public health, safe and effective vaccines against a number of life‐threatening pathogens such as HIV, ebola, influenza, and SARS‐CoV‐2 remain urgently needed. Subunit vaccines can avoid potential toxicity associated with traditional whole virion‐inactivated and live‐attenuated vaccines; however, the immunogenicity of subunit vaccines is often poor. A facile method is here reported to produce lipid nanoparticle subunit vaccines that exhibit high immunogenicity and elicit protection against influenza virus. Influenza hemagglutinin (HA) immunogens are functionalized on the surface of liposomes via stable metal chelation chemistry, using a scalable advanced microfluidic mixing technology (NanoAssemblr). Immunization of mice with HA‐liposomes elicits increased serum antibody titers and superior protection against highly pathogenic virus challenge compared with free HA protein. HA‐liposomal vaccines display enhanced antigen deposition into germinal centers within the draining lymph nodes, driving increased HA‐specific B cell, and follicular helper T cell responses. This work provides mechanistic insights into highly protective HA‐liposome vaccines and informs the rational design and rapid production of next generation nanoparticle subunit vaccines.
Photodetectors of 2D Materials from Ultraviolet to Terahertz Waves
Authors: Qiu Qinxi , Huang Zhiming
Published: March 2021

2D materials are considered to be the most promising materials for photodetectors due to their unique optical and electrical properties. Since the discovery of graphene, many photodetectors based on 2D materials have been reported. However, the low quantum efficiency, large noise, and slow response caused by the thinness of 2D materials limit their application in photodetectors. Here, recent progress on 2D material photodetectors is reviewed, covering the spectrum from ultraviolet to terahertz waves. First the interaction of 2D materials with light is analyzed in terms of optical physics. Then the present methods to improve the performance of 2D material photodetectors are summarized, such as defect engineering, p–n junctions and hybrid detectors, and the issue of serious overestimation of the performance in reported photodetectors based on 2D materials is discussed. Next, a comparison of 2D material photodetectors with traditional commercially available detectors shows that it is difficult to balance the current 2D material photodetectors with regard to having simultaneously both high sensitivity and fast response. Finally, a possible novel EIW mechanism is suggested to advance the performance of 2D material photodetectors in the future.
General Design Methodology for Organic Eutectic Electrolytes toward High‐Energy‐Density Redox Flow Batteries
Authors: Zhang Changkun , Chen Hui , Qian Yumin , Dai Gaole , Zhao Yu , Yu Guihua
Published: March 2021

By virtue of strong molecular interactions, eutectic electrolytes provide highly concentrated redox‐active materials without other auxiliary solvents, hence achieving high volumetric capacities and energy density for redox flow batteries (RFBs). However, it is critical to unveil the underlying mechanism in this system, which will be undoubtedly beneficial for their future research on high‐energy storage systems. Herein, a general formation mechanism of organic eutectic electrolytes (OEEs) is developed, and it is found that molecules with specific functional groups such as carbonyl (CO), nitroxyl radical (NO•), and methoxy (OCH3) groups can coordinate with alkali metal fluorinated sulfonylimide salts (especially for bis(trifluoromethanesulfonyl)imide, TFSI), thereby forming OEEs. Molecular designs further demonstrate that the redox‐inactive methoxy group functionalized ferrocene derivative maintains the liquid OEE at both reduced and oxidized states. Over threefold increase in solubility is obtained (2.8 m for ferrocene derivative OEE) and high actual discharge energy density of 188 Wh L‐1 (75% of the theoretical value) is achieved in the Li hybrid cell. The established mechanism presents new ways of designing desirable electrolytes through molecular interactions for the development of high‐energy‐density organic RFBs.
Efficient and Stable Red Perovskite Light‐Emitting Diodes with Operational Stability >300 h
Authors: Li Hanming , Lin Hong , Ouyang Dan , Yao Canglang , Li Can , Sun Jiayun , Song Yilong , Wang Yufeng , Yan Yanfa , Wang Yong , Dong Qingfeng , Choy Wallace C. H.
Published: March 2021

The long‐term operational stability of perovskite light‐emitting diodes (PeLEDs), especially red PeLEDs with only several hours typically, has always faced great challenges. Stable β‐CsPbI3 nanocrystals (NCs) are demonstrated for highly efficient and stable red‐emitting PeLEDs through incorporation of poly(maleic anhydride‐alt‐1‐octadecene) (PMA) in synthesizing the NCs. The PMA can chemically interact with PbI2 in the precursors via the coupling effect between O groups in PMA and Pb2+ to favor crystallization of stable β‐CsPbI3 NCs. Meanwhile, the cross‐linked PMA significantly reduces the PbCs anti‐site defect on the surface of the β‐CsPbI3 NCs. Benefiting from the improved crystal phase quality, the photoluminescence quantum yield for β‐CsPbI3 NCs films remarkably increases from 34% to 89%. The corresponding red‐emitting PeLEDs achieves a high external quantum efficiency of 17.8% and superior operational stability with the lifetime, the time to half the initial electroluminescence intensity (T50) reaching 317 h at a constant current density of 30 mA cm−2.
Manganese(I)‐Catalyzed Site‐Selective C6‐Alkenylation of 2‐Pyridones Using Alkynes via C−H Activation
Authors: Wan Shanhong , Luo Zhenli , Xu Xin , Yu Haiyang , Li Jiajie , Pan Yixiao , Zhang Xin , Xu Lijin , Cao Rui
Published: March 2021

A Mn(I)‐catalyzed chelation‐assisted direct C6−H alkenylation of 2‐pyridones with both terminal and internal alkynes in a highly regio‐ and stereo‐selective manner has been developed. The catalytic system consisting of Mn(CO)5Br catalyst and KOAc additive allows 1‐(2‐pyridyl)‐2‐pyridones to undergo alkenylation with various terminal alkynes in methyl tert‐butyl ether (MTBE) to furnish the C6‐alkenylated 2‐pyridone products in high yields, and the alkenylation with internal alkynes occurs in CH2Cl2 at increased catalyst and additive loadings. Mechanistic studies suggest the involvement of a five‐membered organomanganese as the key intermediate in the catalytic cycle.

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A High‐Affinity Calmodulin‐Binding Site in the CyaA Toxin Translocation Domain is Essential for Invasion of Eukaryotic Cells
Authors: Voegele Alexis , Sadi Mirko , O'Brien Darragh Patrick , Gehan Pauline , Raoux‐Barbot Dorothée , Davi Maryline , Hoos Sylviane , Brûlé Sébastien , Raynal Bertrand , Weber Patrick , Mechaly Ariel , Haouz Ahmed , Rodriguez Nicolas , Vachette Patrice , Durand Dominique , Brier Sébastien , Ladant Daniel , Chenal Alexandre
Published: March 2021

The molecular mechanisms and forces involved in the translocation of bacterial toxins into host cells are still a matter of intense research. The adenylate cyclase (CyaA) toxin from Bordetella pertussis displays a unique intoxication pathway in which its catalytic domain is directly translocated across target cell membranes. The CyaA translocation region contains a segment, P454 (residues 454–484), which exhibits membrane‐active properties related to antimicrobial peptides. Herein, the results show that this peptide is able to translocate across membranes and to interact with calmodulin (CaM). Structural and biophysical analyses reveal the key residues of P454 involved in membrane destabilization and calmodulin binding. Mutational analysis demonstrates that these residues play a crucial role in CyaA translocation into target cells. In addition, calmidazolium, a calmodulin inhibitor, efficiently blocks CyaA internalization. It is proposed that after CyaA binding to target cells, the P454 segment destabilizes the plasma membrane, translocates across the lipid bilayer and binds calmodulin. Trapping of CyaA by the CaM:P454 interaction in the cytosol may assist the entry of the N‐terminal catalytic domain by converting the stochastic motion of the polypeptide chain through the membrane into an efficient vectorial chain translocation into host cells.
Toxicogenomic Profiling of 28 Nanomaterials in Mouse Airways
Authors: Kinaret Pia A. S. , Ndika Joseph , Ilves Marit , Wolff Henrik , Vales Gerard , Norppa Hannu , Savolainen Kai , Skoog Tiina , Kere Juha , Moya Sergio , Handy Richard D. , Karisola Piia , Fadeel Bengt , Greco Dario , Alenius Harri
Published: March 2021

Toxicogenomics opens novel opportunities for hazard assessment by utilizing computational methods to map molecular events and biological processes. In this study, the transcriptomic and immunopathological changes associated with airway exposure to a total of 28 engineered nanomaterials (ENM) are investigated. The ENM are selected to have different core (Ag, Au, TiO2, CuO, nanodiamond, and multiwalled carbon nanotubes) and surface chemistries (COOH, NH2, or polyethylene glycosylation (PEG)). Additionally, ENM with variations in either size (Au) or shape (TiO2) are included. Mice are exposed to 10 µg of ENM by oropharyngeal aspiration for 4 consecutive days, followed by extensive histological/cytological analyses and transcriptomic characterization of lung tissue. The results demonstrate that transcriptomic alterations are correlated with the inflammatory cell infiltrate in the lungs. Surface modification has varying effects on the airways with amination rendering the strongest inflammatory response, while PEGylation suppresses toxicity. However, toxicological responses are also dependent on ENM core chemistry. In addition to ENM‐specific transcriptional changes, a subset of 50 shared differentially expressed genes is also highlighted that cluster these ENM according to their toxicity. This study provides the largest in vivo data set currently available and as such provides valuable information to be utilized in developing predictive models for ENM toxicity.
Prefrontal cortex and cognitive aging in macaque monkeys
Authors: Upright Nicholas A. , Baxter Mark G.
Published: March 2021

Cognitive impairments that accompany aging, even in the absence of neurodegenerative diseases, include deficits in executive function and memory mediated by the prefrontal cortex. Because of the unique differentiation and expansion of the prefrontal cortex in primates, investigations of the neurobiological basis of cognitive aging in nonhuman primates have been particularly informative about the potential basis for age‐related cognitive decline in humans. We review the cognitive functions mediated by specific subregions of prefrontal cortex, and their corresponding connections, as well as the evidence for age‐related alterations in specific regions of prefrontal cortex. We also discuss evidence for similarities and differences in the effects of aging on prefrontal cortex across species.
Less Unfavorable Salt Bridges on the Enzyme Surface Result in More Organic Cosolvent Resistance
Authors: Cui Haiyang , Eltoukhy Lobna , Zhang Lingling , Markel Ulrich , Jaeger Karl‐Erich , Davari Mehdi D. , Schwaneberg Ulrich
Published: March 2021

Biocatalysis for the synthesis of fine chemicals is highly attractive but usually requires organic (co‐)solvents (OSs). However, native enzymes often have low activity and resistance in OSs and at elevated temperatures. Herein, we report a smart salt bridge design strategy for simultaneously improving OS resistance and thermostability of the model enzyme, Bacillus subtilits Lipase A (BSLA). We combined comprehensive experimental studies of 3450 BSLA variants and molecular dynamics simulations of 36 systems. Iterative recombination of four beneficial substitutions yielded superior resistant variants with up to 7.6‐fold (D64K/D144K) improved resistance toward three OSs while exhibiting significant thermostability (thermal resistance up to 137‐fold, and half‐life up to 3.3‐fold). Molecular dynamics simulations revealed that locally refined flexibility and strengthened hydration jointly govern the highly increased resistance in OSs and at 50–100 °C. The salt bridge redesign provides protein engineers with a powerful and likely general approach to design OSs‐ and/or thermal‐resistant lipases and other α/β‐hydrolases.
A Deep‐UV Nonlinear Optical Borosulfate with Incommensurate Modulations
Authors: Li Yanqiang , Zhou Zhengyang , Zhao Sangen , Liang Fei , Ding Qingran , Sun Junliang , Lin Zheshuai , Hong Maochun , Luo Junhua
Published: March 2021

Despite borate‐sulfates composed of isolated borate and sulfate groups have been discovered for more than one century, borosulfates of B‐O‐S bonding have not been synthesized until 2012 and their properties remain rarely explored. Here, we report a new borosulfate, namely LiRb4[B(SO4)4], which shows potential as a bran‐new class of deep‐UV nonlinear optical (NLO) material. Remarkably, according to the in situ single‐crystal X‐ray diffraction, LiRb4[B(SO4)4] undergoes successive first‐order phase transitions with incommensurate structural modulations under room temperature and low temperature with (3 + 1)D superspace groups of X2(α0γ)0 and P21(α0γ)0, respectively. The first‐principle calculations and structural analyses reveal that NLO properties, phase transitions, and incommensurate modulations are closely related to the [B(SO4)4]5− super‐tetrahedral units with B‐O‐S bonding. We anticipate that the unprecedented coexistence of deep‐UV transparency, NLO responses, and incommensurate structural modulations in one borosulfate will bring new possibilities to understand the underlying concepts of physics and chemistry in aperiodic materials.