bluuebunny/crossref_metadata_2025 huggingface dataset:
Dependency management bots in open-source systems—prevalence and adoption
Authors: Erlenhov Linda , de Oliveira Neto Francisco Gomes , Leitner Philipp
Published: March 2022

Bots have become active contributors in maintaining open-source repositories. However, the definitions of bot activity in open-source software vary from a more lenient stance encompassing every non-human contributions vs frameworks that cover contributions from tools that have autonomy or human-like traits (i.e., Devbots). Understanding which of those definitions are being used is essential to enable (i) reliable sampling of bots and (ii) fair comparison of their practical impact in, e.g., developers’ productivity. This paper reports on an empirical study composed of both quantitative and qualitative analysis of bot activity. By analysing those two bot definitions in an existing dataset of bot commits, we see that only 10 out of 54 listed tools (mainly dependency management) comply with the characteristics of Devbots. Moreover, five of those Devbots have similar patterns of contributions over 93 projects, such as similar proportions of merged pull-requests and days until issues are closed. Our analysis also reveals that most projects (77%) experiment with more than one bot before deciding to adopt or switch between bots. In fact, a thematic analysis of developers’ comments in those projects reveal factors driving the discussions about Devbot adoption or removal, such as the impact of the generated noise and the needed adaptation in development practices within the project.
Effect of neural network structure in accelerating performance and accuracy of a convolutional neural network with GPU/TPU for image analytics
Authors: Ravikumar Aswathy , Sriraman Harini , Sai Saketh P. Maruthi , Lokesh Saddikuti , Karanam Abhiram
Published: March 2022

Background

In deep learning the most significant breakthrough in the field of image recognition, object detection language processing was done by Convolutional Neural Network (CNN). Rapid growth in data and neural networks the performance of the DNN algorithms depends on the computation power and the storage capacity of the devices.

Methods

In this paper, the convolutional neural network used for various image applications was studied and its acceleration in the various platforms like CPU, GPU, TPU was done. The neural network structure and the computing power and characteristics of the GPU, TPU was analyzed and summarized, the effect of these on accelerating the tasks is also explained. Cross-platform comparison of the CNN was done using three image applications the face mask detection (object detection/Computer Vision), Virus Detection in Plants (Image Classification: agriculture sector), and Pneumonia detection from X-ray Images (Image Classification/medical field).

Results

The CNN implementation was done and a comprehensive comparison was done on the platforms to identify the performance, throughput, bottlenecks, and training time. The CNN layer-wise execution in GPU and TPU is explained with layer-wise analysis. The impact of the fully connected layer and convolutional layer on the network is analyzed. The challenges faced during the acceleration process were discussed and future works are identified.
Titanium dioxide dental implants surfaces related oxidative stress in bone remodeling: a systematic review
Authors: Abdulhameed Elaf Akram , Al-Rawi Natheer H. , Omar Marzuki , Khalifa Nadia , Samsudin A.B. Rani
Published: March 2022

Background

Titanium dioxide dental implants have a controversial effect on reactive oxygen species (ROS) production. ROS is necessary for cellular signal transmission and proper metabolism, but also has the ability to cause cell death as well as DNA, RNA, and proteins damage by excessive oxidative stress. This study aimed to systematically review the effect of titanium dioxide dental implant-induced oxidative stress and its role on the osteogenesis-angiogenesis coupling in bone remodeling.

Methods

This systematic review was performed conforming to preferred reporting items for systematic review and meta-analysis (PRISMA) model. Four different databases (PubMed, Science Direct, Scopus and Medline databases) as well as manual searching were adopted. Relevant studies from January 2000 till September 2021 were retrieved. Critical Appraisal Skills Programme (CASP) was used to assess the quality of the selected studies.

Results

Out of 755 articles, only 14 which met the eligibility criteria were included. Six studies found that titanium dioxide nanotube (TNT) reduced oxidative stress and promoted osteoblastic activity through its effect on Wnt, mitogen-activated protein kinase (MAPK) and forkhead box protein O1 (FoxO1) signaling pathways. On the other hand, three studies confirmed that titanium dioxide nanoparticles (TiO2NPs) induce oxidative stress, reduce ostegenesis and impair antioxidant defense system as a significant negative correlation was found between decreased SIR3 protein level and increased superoxide (O2•-). Moreover, five studies proved that titanium implant alloy enhances the generation of ROS and induces cytotoxicity of osteoblast cells via its effect on NOX pathway.

Conclusion

TiO2NPs stimulate a wide array of oxidative stress related pathways. Scientific evidence are in favor to support the use of TiO2 nanotube-coated titanium implants to reduce oxidative stress and promote osteogenesis in bone remodeling. To validate the cellular and molecular cross talk in bone remodeling of the present review, well-controlled clinical trials with a large sample size are required.
Procesos sociodemográficos y alquileres turísticos en centros históricos. Los casos de Sevilla y Cádiz
Authors: Parralejo Julio-José , Díaz-Parra Ibán , Pedregal Belén
Published: March 2022

El impacto del Covid-19 ha supuesto una brusca paralización del turismo generando incertidumbre a nivel internacional. En este marco, el último periodo de auge del sector, correspondiente a la recuperación económica en 2012 y la abrupta nueva recesión en 2020, supone un periodo privilegiado para examinar los impactos del turismo en los centros urbanos. Este trabajo analiza la relación entre procesos sociodemográficos y el alquiler turístico en el último periodo de auge del turismo, tomando como caso de estudio los centros históricos de dos ciudades andaluzas de marcado carácter turístico: Sevilla y Cádiz. El análisis se fundamenta en los datos sociodemográficos suministrados por el Censo de población y vivienda y el Padrón de habitantes, junto a información de alquileres suministrados por distintas fuentes. Como resultado, el trabajo demuestra estadísticamente la relación de la distribución de los alquileres turísticos con varios procesos sociodemográficos y su influencia en la pérdida de población.
Morphological Study of Human Cadaveric Liver and its Surgical Significance
Authors: Dawani Pooja , Patil Krishna , Kathole Mahendra Ambadasji , Kohli Mangala
Published: March 2022

Introduction: The liver is the largest organ of the abdominal viscera. Knowledge of anatomy of liver and its variations is indispensable for accurate diagnosis of cases by radiologists, and prevention of unwanted surgical complications by surgeons. Many researchers have studied the segmental anatomy of the liver, but there are very few studies regarding the surface variations of liver. Aim: To document the surface variations of liver and discuss them from clinical perspective. Materials and Methods: This observational cross-sectional study was conducted from August 2015 to May 2019 on 50 liver specimens in the Department of Anatomy, Vardhman Mahavir Medical College. These livers were observed for any surface variations such as abnormal fissures or lobes, elongation or hypoplasia of lobes, etc. Data were tabulated and stats were calculated in percentages. Descriptive analysis of data has been carried out and mentioned in the study. Results: In the present study, out of 50 liver specimens, variations were observed in 42 (84%) specimens. Accessory fissures were seen in 16 (32%) specimens. Elongated left lobe was present in 7 (14%) specimens. Pons hepatis, which is a bridge of tissue connecting the quadrate lobe and the left lobe was observed in 8(16%) specimens. Caudate lobe variations observed in this study were abnormal fissures and hypertrophied papillary process. Conclusion: The present study documents frequent morphological variations of liver such as elongated left lobe, accessory lobes, etc. Elongated left lobe may be related to fundus of stomach which should be kept in mind during left lobe resection. The radiologists can confuse accessory lobes or projections with pathological mass. Knowledge of these variations will undoubtedly help radiologists and surgeons to prevent misdiagnosis of cases and plan newer and safer surgical procedures.
Conceptualising the Scale to Quantify E-Readiness of Farmers: Sri Lankan View
Authors: Sachitra Vilani , Padmini Chandra
Published: March 2022

E-agriculture is vital for supporting the development in agricultural sector. Before developing any e-agriculture technology, it is essential to measure e-readiness as it will be an indicator to foresee the application of the developed technology. This has necessitated the concept of e-readiness. The literature has not yet adequately assessed the farmers’ e-readiness level due to a lack of contextually appropriate assessment tools. This study aims to identify factors that contribute to measure e-readiness of farmers in Sri Lanka and constructing and standardising a scale that can be used to quantitatively score e-readiness across each of these factors. The study utilized the criteria 8Cs developed by Rao and embraced a structured literature review approach to identify measurement items to 8Cs. To finalise the statements, the study used mean value and Kendall’s coefficient of concordance. The analysis of the literature demonstrates that most of the indicators of e-readiness related to technology infrastructure, human skills, people and accessibility and connectivity. However, the challenge is to construct a comprehensive model that would incorporate all the major driving forces of an economy that would directly effect on the improvement of e-agriculture. We proposed 89 independent measures across eight factors. This paper provides a first attempt to conceptualise the scale to quantify the e-readiness of farmers in Sri Lanka utilizing the criteria 8Cs. The proposed assessment framework would rectify the areas excluded by the existing e-readiness tools and provide a more inclusive foundation for measuring and monitoring e-readiness in agricultural community. The study will be useful to know farmers’ preparedness and ability to use technological devices. The e-readiness measurement will be utilized to evaluate the farming community’s readiness to engage in e-activities such as e-commerce, e-learning and e-government.
Effect of Customer Satisfaction on the Profitability of the Sacco Sector in Kenya. A Case of Thamani Sacco Society Limited Tharaka Nithi County
Authors: Nyaga Morris A. Mugendi , Obuba Robert Omundi
Published: March 2022

SACCOs are on the forefront to offer financial services to their members, with the liberalization of financial industry in Kenya, this has brought in more financial institutions providing accessible cheap loans. As a result of this, financial institutions including SACCOs are competing to attract and serve the same customers. The study sought to establish the effect of customer satisfaction on the profitability of Thamani SACCO in Tharaka Nithi County. The accessible population of the study are 45 selected employees of Thamani SACCO drawn from all the 5 branches in the County. Descriptive research design was adopted to conduct this study. Data collection was by means of a structured questionnaire utilizing both closed and open-ended questions. Qualitative data was analysed via the coding of themes and concepts from which generalization was conducted. Quantitate data was analysed using descriptive statistics (frequency distribution table) Inferential statistics used included ANOVA techniques and correlation analysis to establish the relationship between research variables. The questionnaire was pre-tested to establish the reliability and viability of the questionnaire instrument. The study findings revealed a strong and substantial correlation between Sacco profitability and Customer satisfaction indicators (r=0.554, p=0.000) and that customer Satisfaction and Sacco Profitability were positively and significantly related (β =0.137, p=0.001), The study recommended that the Sacco sector in Tharaka Nithi County can use customer satisfaction as a strategic action to enhance Sacco profitability and counter competitive pressure in the industry, the study further recommended for a different study looking at the different Customer satisfaction indicators affecting Sacco profitability in Kenya.
Phytochemical Profiling and Pharmacognostic Evaluation of Oldenlandia corymbosa and Ocimum sanctum Leaves Hydroalcoholic Extracts: Comparative Study
Authors: Das Shaktijit , Ghosh Pranabesh , Ghosh Chandreyi , Saha Moumita , Hazra Alok K. , Chatterje Sirshendu
Published: March 2022

Herbs are an important source of bioactive substances. These are widely used to treat several disorders for better function in the human body, minimum toxic effects, and widespread availability. A total of two medicinal herbs from West Bengal, India, such as Oldenlandia corymbosa (Diamond flower) and Ocimum sanctum (Holy basil), are being considered for inclusion in the current study. Hydroalcoholic extracts (70% ethanolic) of the two plants' leaves were analyzed to detect and quantify important phytochemical substances and investigate in vitro antioxidant and pharmacological effects. Spectrophotometric and HPLC-DAD techniques were used for the quantitative estimation of different phytochemicals. In addition, in vitro antimicrobial properties were studied using the Kirby-Bauer paper disc diffusion method. Several assays have been performed on the medicinal plant Oldenlandia corymbosa (OC). The results have been compared to those obtained from a traditional medical plant, Ocimum sanctum (OS) for the first time to our knowledge. Results showed that OS contains a higher quantity of polyphenols, flavonoids, and has higher antioxidant potential with respect to OC. Similar trends were observed for polysaccharides contents. In contrast, OC contains a higher quantity of tannins, alkaloids, and protein and higher in vitro antibacterial and anti-diabetic properties. HPLC-DAD-based profiling of eight important phenolic constituents viz. Gallic acid, catechin hydrate, chlorogenic acid, caffeic acid, syringic acid, p-coumaric acid, sinapic acid, coumarin, quercetin, and kaempferol, were performed. The current study concluded that Oldenlandia corymbosa has many bioactive phenolics in considerable amounts compared to the highly established medicinal herb OS leaves extracts. The current study demonstrates the pharmacological significance of Oldenlandia corymbosa that may generate enthusiasm among researchers and those working in the pharmaceutical industry.
BUSINESS PHILOSOPHY OF SELECTED BICOLANO ENTREPRENEURS: DISSECTING THEIR VIEWS AND INSIGHTS
Authors: De Luna Yumi Vivien
Published: March 2022

This study aimed to seek views from selected Bicolano entrepreneurs on how they run their business, the values they believed, challenges they experienced with the current pandemic and their future plans as well. It was qualitative research that made used of structured interview and content analysis. Findings showed that Bicolano entrepreneurs’ views on the different themes were not clearly separated from each other. Most of them started the business as additional source of income. These entrepreneurs were strongly driven by their particular advocacies. In terms of core values, most of them agreed that dedication to work was viable in making business successful. The business philosophy that stood out among them was making customer satisfaction a priority. The resilience of the Bicolano entrepreneur amidst the pandemic was manifested by their continuous marketing innovations adapting to the situation.
THE ROLE OF COMPETENCIES, FINANCIAL PLANNING, AND ACCESS TO FINANCE IN EXPLAINING SMES FINANCIAL INNOVATION
Authors: Ismanto Hadi , Pratiwi Tantri , Zulianti Nurin , Qofur Akhmad Abdul
Published: March 2022

Finance was a crucial aspect for the survival of SMEs. This study explored the factors that can influence financial innovation. Data was collected from the results of distributing questionnaires to 285 SMEs using a door-to-door approach and filling assistance. Sampling was based on the proportion of small and medium-sized industries. The data were tested with a series of statistical tests to obtain a suitable regression result. These results indicated that financial innovation was influenced by the owner or manager's entrepreneurial com­petence. Meanwhile, access to finance and financial planning did not affect financial innovation. Additional funds from outside the company were deemed necessary when the owner or manager of SMEs applies their maximum competence for business growth and performance. Therefore, it forced SMEs to be smart in exploring financial sources. SMEs tent to use their finance access to finance their business operations rather than making financial innovations. SMEs did not think about exploring their finances anymore because they feelt they had enough loans obtained from one institution. Even though the knowledge of SME owner or manager financial planning was quite good; they prefered not to make financial planning and let the cash flow normally.
Transferência Tecnológica na Pecuária Leiteira: um estudo sob o enfoque dos produtores das Regiões do Vale do Mucuri (MG) e do Extremo Sul da Bahia
Authors: Maciel Laíse Nunes , Trindade Lucas Xavier , Dos Santos Farlei Cosme Gomes , Pereira João Pedro de Castro Nunes
Published: March 2022

Embora a tecnologia desempenhe papel de destaque para a competitividade da agropecuária brasileira, existem segmentos e regiões situados à margem do desenvolvimento em função da baixa produtividade e da pobreza em decorrência do reduzido aporte tecnológico existente nas unidades produtivas rurais. Esta investigação do tipo survey aplicado a 20 produtores teve como objetivo diagnosticar a percepção desses agentes frente às principais condicionantes associadas ao fenômeno da transferência de tecnologia para unidades de produção de leite das localidades do Vale do Mucuri (MG) e do Extremo Sul da Bahia. Ficou evidenciado que, embora os produtores tenham disposição favorável para adotarem tecnologias e a considerem um relevante fator de produção para a pecuária leiteira, outras condicionantes não se mostram favoráveis à concretização da transferência de tecnologia e denotam fraquezas existentes nesse processo. Foi constatado também que inexistem diferenças significativas de percepção dos produtores frente às condicionantes em função da localidade e do tamanho de suas respectivas unidades de produção.
A Indústria de Telessaúde como uma Oportunidade para o Desenvolvimento Econômico na Saúde Pública Brasileira
Authors: Silva Angélica Baptista , De Mendonça Gisele Cruz
Published: March 2022

Nas últimas décadas observa-se um aumento da aplicação das tecnologias da informação e da comunicação nas variadas áreas da assistência à saúde. Faz-se importante conhecer o cenário da proteção intelectual deste setor tecnológico. Para tanto foi realizada a revisão da literatura de patente em telessaúde – em particular, a videoconferência. O cenário mundial de proteção por patente se apresenta em franco crescimento. Quanto às empresas, verifica-se a predominância da presença das multinacionais, no Brasil. A série temporal denota crescimento de depósitos na mesma época de altos investimentos públicos em telessaúde no Sistema Único de Saúde. Os resultados da análise no cenário internacional evidenciaram que há poucos depósitos no Brasil, o que denota a impossibilidade de a indústria local reproduzir a tecnologia. A aliança entre empresas brasileiras e universidades, com os gestores do setor saúde emerge como possível caminho estratégico para o desenvolvimento tecnológico e a inovação, através do qual o poder de compra do Estado induziria a indústria local.
Pensamento Empreendedor, uma Alternativa para a Internalização do Empreendedorismo
Authors: Carvalho Sônia Marise Salles , Martin Adriana Regina , Dantas Agnaldo Almeida , Carvalho Fernanda Zambon , Mazzei Debora Franceschini
Published: March 2022

A importância dada ao empreendedorismo na atualidade é indiscutível. Ele está relacionado com a economia dos países e com a forma como a sociedade se estrutura, No Brasil, existem mais de 50 milhões de pessoas com negócios próprios. Com essa temática de base, este artigo procura refletir sobre as questões trazidas por Jan Spruijt (2017) em seu artigo “Paradoxos do Pensamento Empresarial: por que o empreendedorismo dificilmente pode ser ensinado?” e sugerir possíveis reflexões ou mudanças na forma de atuação de universidades que contemplam disciplinas de empreendedorismo em suas grades curriculares e do Serviço de Apoio às Micro e Pequenas Empresas (SEBRAE) – em especial para algumas de suas ações educacionais – visto ser sua missão: “Promover a competitividade e o desenvolvimento sustentável dos pequenos negócios e fomentar o empreendedorismo, para fortalecer a economia nacional”. O artigo foi elaborado a partir da metodologia de pesquisa exploratória de base bibliográfica e documental, com uma abordagem analítica, fazendo com que se reflita sobre as linhas de estudo que colaboram para o entendimento de Spruijt, modelos ou práticas para ensino do empreendedorismo, paradoxos do pensamento empreendedor e da prática do ensino do empreendedorismo.
Inovação e Sustentabilidade: proposta de política pública para o desenvolvimento de parque tecnológico voltado à sociobiodiversidade amapaense
Authors: De Oliveira Márcio Luis Góes , Garçon José Erivan Ferreira , Costa Robson Antonio Tavares
Published: March 2022

O Amapá ocupa a penúltima posição nos índices de competitividade entre os estados. Porém, compreende-se que o estado possui potencialidades que desenvolvidas de maneira sustentável podem reduzir o atraso econômico local. Assim, este estudo tem o propósito de propor uma política pública para a criação de um parque tecnológico no Amapá e, para tanto, analisará a relação sociobiodiversidade amapaense com as potencialidades de instituições científicas e tecnológicas, universidades e institutos de pesquisa. Como espaço, a pesquisa limitou-se aos municípios de Macapá e Santana, caracterizando-se como um estudo de caso, lançando mão da análise de indicadores socioeconômicos que demonstrassem o perfil regional. Baseado nos estudos realizados, foi proposto um fluxo com ações para a viabilização de um possível parque tecnológico no Amapá. Porém, verificou-se que, para a criação de um parque tecnológico no estado, é necessário que haja uma atividade econômica madura, com arranjos produtivos estruturados e atores articulados para o devido suporte aos empreendimentos.
Biossurfactantes: potenciais agentes biorremediadores
Authors: Santos Sidnei Cerqueira dos
Published: March 2022

Os biossurfactantes são moléculas tensoativas que apresentam potencial como agente remediador de ambientes contaminados. A prospecção é uma ferramenta estratégica para identificar inovações tecnológicas. O objetivo deste trabalho foi avaliar as patentes que utilizam biossurfactante no processo de remediação microbiana de ambientes contaminados, para identificar os principais tipos de biossurfactante, os microrganismos produtores e as formas de tratamento. A busca de dados tecnológicos foi realizada nas bases de dados do Questel Orbit, usando-se uma combinação de palavras-chave e códigos da Classificação Internacional de Patentes. Foram selecionadas 76 patentes para análise. A China destaca-se como a maior detentora de patentes. As inovações tecnológicas mais depositadas foram relacionadas com o biossurfactante ramnolipídeo, produzido por Pseudomonas aeruginosa. Esta pesquisa indica que o melhor cenário para desenvolvimento tecnológico é para remediação de metais pesados.
Resilient finite‐time fault detection dissipative‐based filter for semi‐Markovian jump systems with incomplete measurements
Authors: Sakthivel Rathinasamy , Nithya Venkatesan , Suveetha Veeralpatti Thangavel
Published: March 2022

In this article, the problem of resilient finite‐time fault detection dissipative‐based filter design is investigated for a class discrete‐time semi‐Markovian jump systems with incomplete measurements, dynamic quantization and time‐varying delay. The considered system includes various network‐induced imperfections such as missing measurements, transmission delay and dynamic signal quantization. Specifically, all these imperfections are modeled using stochastic variables following Bernoulli random distribution. In addition, the transition probability of the semi‐Markov process is time‐varying along with the lower and upper bounds of the transition rate. Eventually, a set of sufficient conditions is derived in terms of linear matrix inequalities (LMIs) by assuming proper Lyapunov–Krasovskii functional and using S‐procedure lemma such that the augmented filtering error system is stochastically finite‐time bounded with prescribed dissipative performance. Finally, the applicability and usefulness of the proposed filter design is demonstrated through a pulse‐width‐modulation‐boost‐converter (PWM) model.
A Novel Biasing Scheme of Electrolyte‐Gated Organic Transistors for Safe In Vivo Amplification of Electrophysiological Signals
Authors: Di Lauro Michele , Zucchini Elena , De Salvo Anna , Delfino Emanuela , Bianchi Michele , Murgia Mauro , Carli Stefano , Biscarini Fabio , Fadiga Luciano
Published: March 2022

Successful translation of organic transistors as sensors and transducers to clinical settings is hampered by safety and stability issues. The operation of such devices demands driving voltages across the biotic/abiotic interface, which may result in undesired electrochemical reactions that may harm both the patient and the device. In this study, a novel operational mode is presented for electrolyte‐gated organic transistors that avoid these drawbacks: the common‐drain/grounded‐source configuration. This approach reverts the standard common‐source/common‐ground configuration and achieves maximum signal amplification while applying null net bias across the electrolyte, with no parasitic currents. The viability of the proposed configuration is demonstrated by recording in vivo the somatosensory evoked activity from the barrel cortex of rats. The main inherent advantage of transistors with respect to passive electrodes is preserved in the proposed scheme: a superior signal‐to‐noise ratio is achieved which enables the detection of evoked activity at the single‐trial level. Then, common‐drain/grounded‐source organic transistors are proposed as ideal candidate devices for a harmless translational recording platform.
A Method for Deconvoluting and Quantifying the Real‐Time Species Fluxes and Ionic Currents Using In Situ Electrochemical Quartz Crystal Microbalance
Authors: Zheng Kai , Xian Yongqiu , Lin Zifeng
Published: March 2022

Electrochemical quartz crystal microbalance (EQCM) is a powerful tool to screen the gravimetric response of electrochemically active electrodes. In this study, a method is proposed to deconvolute and quantify the real‐time fluxes and ionic currents of different species based on the EQCM measurement results. This work creatively conceptualizes the flux cyclic voltammograms (CVs) and ionic current CVs, and applys them to analyze the real‐time molecules and ion evolution. As a proof of concept, Ti3C2Tx MXene, the most studied 2D metal carbide, is investigated as a supercapacitor electrode in 1 m H2SO4 electrolyte. The real‐time H2O and H+ fluxes are obtained using the proposed approach and corresponding flux CVs are constructed. The potential‐dependent evolution of H2O and H+ fluxes suggest that the insertion of hydrated H+ contributes significantly to the double‐layer capacitance. The H+ CV calculated from the H+ flux overlaps with the experimental measured CV, confirming that H+ is the only interactive charge carrier for screening the Ti3C2Tx electrode charge.
A Chromic and Near‐Infrared Emissive Mechanophore Serving as a Versatile Force Meter in Micelle–Hydrogel Composites
Authors: Yang Fan , Li Xiaopei , Chen Yulan
Published: March 2022

Mechanofluorochromic polymers, which can indicate damage or excessive stress in highly polarized environments with a clearly perceptible optical signal, are potentially useful in a variety of exciting applications. However, most reported fluorochromic mechanophores exhibit poor color contrast and fluorescence penetration, or are irreversible in polarized phase after mechanical activation. Here, this challenge is tackled by designing and engineering a novel near‐infrared (NIR) emissive, rhodanmin derived mechanophore (Rh‐Co) in a kind of hydrogel composites. The ring‐opened Rh‐Co is unique in high molar extinction coefficient and bright NIR emission with such optical transition under force directly corresponding to covalent bond scission and reversibly switchable in an aqueous environment. The hydrogel composites thus can sensitively change their color from yellow to green and emit highly penetrated NIR fluorescence when different types of forces (tension, compression, and friction force) are applied, highlighting the potential applications of Rh‐Co in biocompatible environments as a “force meter.”
Zero‐Dimensional Luminescent Metal Halide Hybrids Enabling Bulk Transparent Medium as Large‐Area X‐Ray Scintillators
Authors: Li Bohan , Xu Yan , Zhang Xinlei , Han Kai , Jin Jiance , Xia Zhiguo
Published: March 2022

Scintillators are critical in medical imaging, non‐destructive security screening, and space exploration applications. However, it still remains a challenge to achieve large‐area and high‐transparency scintillators by a low‐cost and easy‐to‐implement way. Herein, a large transparent medium with a diameter over 10 cm is prepared via a facile melt‐quenching strategy using a stoichiometric mixture of ethyltriphenylphosphonium bromide (ETPBr) and MnBr2 as raw materials. Benefiting from the crystallization behavior of high‐efficiency green‐emitting (ETP)2MnBr4 nanocrystals hybridized with amorphous phase in the transparent wafer, the (ETP)2MnBr4‐based transparent medium as a scintillator evidences a high transparency (over 80%, ranging from 500 to 800 nm), a high light yield of ≈35 000 ± 2000 photon per MeV, a low detection limit of 103 nGy S–1, and a competitive spatial resolution of 13.4 lp mm–1 for X‐ray imaging. This work offers a distinctive simple and fast melt‐quenching methodology to fabricate (ETP)2MnBr4 metal halide X‐ray scintillator wafer with large‐area and shape flexibility, excellent transparency, and high scintillation performance for the medical or industrial X‐ray imaging application.
A Review on the Bioinspired Photocatalysts and Photocatalytic Systems
Authors: Yang Liuqing , Fan Deqi , Li Zhaolin , Cheng Yelan , Yang Xiaofei , Zhang Tierui
Published: March 2022

After long‐term evolution, organisms in nature have achieved optimal structure, organization, and function to adapt to the environment. Some ingenious biological structures have highly efficient solar light absorption, matter transmission, and natural photocatalytic properties, such as leaves, sunflowers, seaweeds, algae, bacteria. Artificial photocatalysis, which involves CO2 reduction and water splitting to obtain green renewable energy or oxygen, is of great significance for solving the problem of energy shortages, achieving carbon neutrality, and building a sustainable society. In order to improve the efficiency of artificial photocatalysis, it is necessary to develop highly efficient photocatalysts by expanding ideas and drawing innovative inspiration from nature. Artificially constructed photocatalysts with bionic structures achieved by simulating natural organisms have gradually become an exciting research field with great potential in recent years. This article reviews bioinspired photocatalysts and photocatalytic systems from the aspects of principle, composition, construction method, and the achieved performance. It is expected that this review will help researchers develop a systematic and in‐depth understanding for the biomimetic design of photocatalysts and photocatalytic systems.
Symmetrically Ion‐Gated In‐Plane Metal‐Oxide Transistors for Highly Sensitive and Low‐Voltage Driven Bioelectronics
Authors: Kang Jingu , Jang Young‐Woo , Moon Sang Hee , Kang Youngjin , Kim Jaehyun , Kim Yong‐Hoon , Park Sung Kyu
Published: March 2022

To provide a unique opportunity for on‐chip scaled bioelectronics, a symmetrically gated metal‐oxide electric double layer transistor (EDLT) with ion‐gel (IG) gate dielectric and simple in‐plane Corbino electrode architecture is proposed. Using amorphous indium‐gallium‐zinc oxide (a‐IGZO) semiconductor and IG dielectric layers, low‐voltage driven EDLTs with high ionotronic effects can be realized. More importantly, in contrast to the conventional asymmetric rectangular EDLTs which can cause non‐uniform potential variation in the active channel layer and eventually degrade the sensing performance, the new symmetrical in‐plane type EDLTs achieve high and spatially uniform ion responsive behaviors. The symmetrically gated a‐IGZO EDLTs exhibited a responsivity of 129.4% to 5 ppm mercury (Hg2+) ions which are approximately three times higher than that with conventional electrode structure (responsivity of 38.5%). To confirm the viability of the new device architectures and the findings, the detailed mechanism of the symmetric gating effects in the in‐plane EDLTs with a variety of electrical characterization and 3D fine element analysis simulations is also discussed.
Deconvolution of Light‐Induced Ion Migration Phenomena by Statistical Analysis of Cathodoluminescence in Lead Halide‐Based Perovskites
Authors: Shirzadi Erfan , Tappy Nicolas , Ansari Fatemeh , Nazeeruddin Mohammad Khaja , Hagfeldt Anders , Dyson Paul J.
Published: March 2022

Studying the compositional instability of mixed ion perovskites under light illumination is important to understand the mechanisms underlying their efficiency and stability. However, current techniques are limited in resolution and are unable to deconvolute minor ion migration phenomena. Here, a method that enables ion migration to be studied allowing different segregation mechanisms to be elucidated is described. Statistical analysis is applied to cathodoluminescence data to generate compositional distribution histograms. Using these histograms, two different ion migration phenomena, horizontal ion migration (HIM) and vertical ion migration (VIM), are identified in different perovskite films. It is found that most passivating agents inhibit HIM, but not VIM. However, VIM can be reduced by deposition of imidazolium iodide on the perovskite surface. This method can be used to study perovskite‐based devices efficiency and stability by providing molecular level mechanistic understanding of passivation approaches leading to performance improvement of perovskite solar cells via rational design.
Pharmacological Perturbation of Mechanical Contractility Enables Robust Transdifferentiation of Human Fibroblasts into Neurons
Authors: He Zheng‐Quan , Li Yu‐Huan , Feng Gui‐Hai , Yuan Xue‐Wei , Lu Zong‐Bao , Dai Min , Hu Yan‐Ping , Zhang Ying , Zhou Qi , Li Wei
Published: March 2022

Direct cell reprogramming, also called transdifferentiation, is valuable for cell fate studies and regenerative medicine. Current approaches to transdifferentiation are usually achieved by directly targeting the nuclear functions, such as manipulating the lineage‐specific transcriptional factors, microRNAs, and epigenetic modifications. Here, a robust method to convert fibroblasts to neurons through targeting the cytoskeleton followed by exposure to lineage‐specification surroundings is reported. Treatment of human foreskin fibroblasts with a single molecule inhibitor of the actomyosin contraction, can disrupt the cytoskeleton, promote cell softening and nuclear export of YAP/TAZ, and induce a neuron‐like state. These neuron‐like cells can be further converted into mature neurons, while single‐cell RNA‐seq shows the homogeneity of these cells during the induction process. Finally, transcriptomic analysis shows that cytoskeletal disruption collapses the original lineage expression profile and evokes an intermediate state. These findings shed a light on the underestimated role of the cytoskeleton in maintaining cell identity and provide a paradigm for lineage conversion through the regulation of mechanical properties.
Size‐Controllable Nickel Sulfide Nanoparticles Embedded in Carbon Nanofibers as High‐Rate Conversion Cathodes for Hybrid Mg‐Based Battery
Authors: Zhu Guilei , Xia Guanglin , Pan Hongge , Yu Xuebin
Published: March 2022

The integration of highly‐safe Mg anode and fast Li+ kinetics endows hybrid Mg2+/Li+ batteries (MLIBs) a promising future, but the practical application is circumvented by the lack of appropriate cathodes that enable the realization of an enough participation of Mg2+ in the reactions, resulting in a high dependence on Li+. Herein, the authors develop a series of size‐controllable nickel sulfide nanoparticles embedded in carbon nanofibers (NiS@C) with synergistic effect of particle diameter and carbon content as the cathode material for MLIBs. The optimized particle size is designed to maximize the utilization of the active material and remit internal stress, and appropriate carbon encapsulation efficiently inhibiting the pulverization of particles and accelerates the ability of conducting ions and electrons. In consequence, the representative NiS@C delivers superior electrochemical performance with a highest discharge capacity of 435 mAh g−1 at 50 mA g−1. Such conversion cathode also exhibits excellent rate performance and remarkable cycle life. Significantly, the conversion mechanism of NiS in MLIBs is unambiguously demonstrated for the first time, affirming the corporate involvement of both Mg2+ and Li+ at the cathodic side. This work underlines a guide for developing conversion‐type materials with high rate capability and cyclic performance for energy storage applications.
Versatile boron‐based thermally activated delayed fluorescence materials for organic light‐emitting diodes
Authors: Han Jianmei , Chen Yanying , Li Nengquan , Huang Zhongyan , Yang Chuluo
Published: March 2022

During the last few years, organoboron‐based thermally activated delayed fluorescence (TADF) materials have received extensive attention in optoelectronic area, owing to the unique electronegativity of boron atom. Herein, many research progress of organoboron‐based TADF materials for organic optoelectronic devices is summarized. This review comprehensively documents the organoboron‐based TADF materials according to the emission colors from blue to red‐near‐infrared (red‐NIR), covering the molecular design strategies, photophysical properties, and optoelectronic performance in organic light‐emitting diodes (OLEDs). The current progress and future challenges in this fast‐growing fields are reviewed systematically, providing instructive guidance for the future research on high‐performance TADF‐OLEDs.
Guided Synthesis of a Mo/Zn Dual Single‐Atom Nanozyme with Synergistic Effect and Peroxidase‐like Activity
Authors: Ma Chong‐Bo , Xu Yaping , Wu Lixin , Wang Quan , Zheng Jia‐Jia , Ren Guoxi , Wang Xiaoyu , Gao Xingfa , Zhou Ming , Wang Ming , Wei Hui
Published: March 2022

We present a facile route towards a dual single‐atom nanozyme composed of Zn and Mo, which utilizes the non‐covalent nano‐assembly of polyoxometalates, supramolecular coordination complexes as the metal‐atom precursor, and a macroscopic amphiphilic aerogel as the supporting substrate. The dual single‐atoms of Zn and Mo have a high content (1.5 and 7.3 wt%, respectively) and exhibit a synergistic effect and a peroxidase‐like activity. The Zn/Mo site was identified as the main active center by X‐ray absorption fine structure spectroscopy and density functional theory calculation. The detection of versatile analytes, including intracellular H2O2, glucose in serum, cholesterol, and ascorbic acid in commercial beverages was achieved. The nanozyme has an outstanding stability and maintained its performance after one year's storage. This study develops a new peroxidase‐like nanozyme and provides a robust synthetic strategy for single‐atom catalysts by utilizing an aerogel as a facile substrate that is capable of stabilizing various metal atoms.
Monoazadichalcogenasumanenes: Synthesis, Structures, and Ring Reconstruction via Atom Transfer under Acidic Conditions
Authors: Shang Jihai , Wang Renjie , Yuan Chengshan , Liu Zitong , Zhang Hao‐Li , Shao Xiangfeng
Published: March 2022

Buckybowls have unique properties that can be tailored by embedding main‐group elements into their π‐scaffolds. Herein, a synthetic approach is developed for producing monoazadichalcogenasumanenes (4 a/4 b, 6 a/6 b, 7 a/7 b) derived from sumanene by replacing its three benzylic carbons with one nitrogen and two chalcogen atoms (S for 4 a/4 b, Se for 6 a/6 b, Te for 7 a/7 b). Monoazadichalcogenasumanenes are deeper π‐bowls than trichalcogensumanenes as the C−N bond is much shorter than C−X (X=S, Se, Te). The bowl‐depth of 4 b (0.95 Å) is greater than that of corannulene (0.85 Å). The nitrogen atom donates electron density to the entire π‐system that makes monoazadichalcogenasumanenes electron‐rich. They undergo ring reconstruction of chalcogenophene ring via transferring a chalcogen atom from one molecule to another under acidic conditions. The nitrogen and chalcogen atoms play crucial role on this reaction.
Coloring Chemistry—How Mindful Color Choices Improve Chemical Communication
Authors: Kaspar Felix , Crameri Fabio
Published: March 2022

Color is a central element to scientific communication, but its use comes with the responsibility to ensure universally accessible and accurate data presentation. This short Viewpoint Article aims to sensitize the chemical community to the importance of mindful color choices in scientific illustrations.
Formation of Breslow Intermediates from N‐Heterocyclic Carbenes and Aldehydes Involves Autocatalysis by the Breslow Intermediate, and a Hemiacetal
Authors: Wessels Alina , Klussmann Martin , Breugst Martin , Schlörer Nils E. , Berkessel Albrecht
Published: March 2022

Under aprotic conditions, the stoichiometric reaction of N‐heterocyclic carbenes (NHCs) such as imidazolidin‐2‐ylidenes with aldehydes affords Breslow Intermediates (BIs), involving a formal 1,2‐C‐to‐O proton shift. We herein report kinetic studies (NMR), complemented by DFT calculations, on the mechanism of this kinetically disfavored H‐translocation. Variable time normalization analysis (VTNA) revealed that the kinetic orders of the reactants vary for different NHC‐to‐aldehyde ratios, indicating different and ratio‐dependent mechanistic regimes. We propose that for high NHC‐to‐aldehyde ratios, the H‐shift takes place in the primary, zwitterionic NHC‐aldehyde adduct. With excess aldehyde, the zwitterion is in equilibrium with a hemiacetal, in which the H‐shift occurs. In both regimes, the critical H‐shift is auto‐catalyzed by the BI. Kinetic isotope effects observed for R‐CDO are in line with our proposal. Furthermore, we detected an H‐bonded complex of the BI with excess NHC (NMR).
Iridium‐Catalyzed Asymmetric Allylic Substitution of Methyl Azaarenes
Authors: Liu Xi‐Jia , Zhang Wen‐Yun , Zheng Chao , You Shu‐Li
Published: March 2022

Herein, an Ir‐catalyzed asymmetric allylic substitution reaction of methyl azaarenes is described. Azaarenes such as (benzo)thiazole, oxazole, benzoimidazole, pyridine, and (iso)quinoline are all tolerated. The corresponding chiral azaarene derivatives are obtained in good yields with high enantioselectivity (up to 96 % yield and 99 % ee). The utilization of the Knochel reagent TMPZnBr⋅LiBr warrants the in situ formation of benzylic nucleophiles without additional activating reagents. 1H NMR studies suggested a two‐fold function of the Knochel reagent in this reaction. The synthetic utility of this method has been showcased by a concise enantioselective synthesis of an allosteric protein kinase modulator.
Atomic‐Layered Cu5 Nanoclusters on FeS2 with Dual Catalytic Sites for Efficient and Selective H2O2 Activation
Authors: Ling Cancan , Liu Xiufan , Li Hao , Wang Xiaobing , Gu Huayu , Wei Kai , Li Meiqi , Shi Yanbiao , Ben Haijie , Zhan Guangming , Liang Chuan , Shen Wenjuan , Li Yaling , Zhao Jincai , Zhang Lizhi
Published: March 2022

Regulating the distribution of reactive oxygen species generated from H2O2 activation is the prerequisite to ensuring the efficient and safe use of H2O2 in the chemistry and life science fields. Herein, we demonstrate that constructing a dual Cu−Fe site through the self‐assembly of single‐atomic‐layered Cu5 nanoclusters onto a FeS2 surface achieves selective H2O2 activation with high efficiency. Unlike its unitary Cu or Fe counterpart, the dual Cu−Fe sites residing at the perimeter zone of the Cu5/FeS2 interface facilitate H2O2 adsorption and barrierless decomposition into ⋅OH via forming a bridging Cu‐O‐O‐Fe complex. The robust in situ formation of ⋅OH governed by this atomic‐layered catalyst enables the effective oxidation of several refractory toxic pollutants across a broad pH range, including alachlor, sulfadimidine, p‐nitrobenzoic acid, p‐chlorophenol, p‐chloronitrobenzene. This work highlights the concept of building a dual catalytic site in manipulating selective H2O2 activation on the surface molecular level towards efficient environmental control and beyond.
A Symmetry‐Based Kinematic Theory for Nanocrystal Morphology Design
Authors: Ni Bing , González‐Rubio Guillermo , Kirner Felizitas , Zhang Siyuan , Cölfen Helmut
Published: March 2022

The growth of crystalline nanoparticles (NPs) generally involves three processes: nucleation, growth, and shape evolution. Among them, the shape evolution is less understood, despite the importance of morphology for NP properties. Here, we propose a symmetry‐based kinematic theory (SBKT) based on classical growth theories to illustrate the process. Based on the crystal lattice, nucleus (or seed) symmetry, and the preferential growth directions under the experimental conditions, the SBKT can illustrate the growth trajectories. The theory accommodates the conventional criteria of the major existing theories for crystal growth and provides tools to better understand the symmetry‐breaking process during the growth of anisotropic structures. Furthermore, complex dendritic growth is theoretically and experimentally demonstrated. Thus, it provides a framework to explain the shape evolution, and extends the morphogenesis prediction to cases, which cannot be treated by other theories.
Manganese‐Catalyzed Asymmetric Hydrogenation of 3H‐Indoles
Authors: Liu Chenguang , Wang Mingyang , Xu Yihan , Li Yibiao , Liu Qiang
Published: March 2022

The asymmetric hydrogenation (AH) of 3H‐indoles represents an ideal approach to the synthesis of useful chiral indoline scaffolds. However, very few catalytic systems based on precious metals have been developed to realize this challenging reaction. Herein, we report a Mn‐catalyzed AH of 3H‐indoles with excellent yields and enantioselectivities. The kinetic resolution of racemic 3H‐indoles by AH was also achieved with high s‐factors to construct quaternary stereocenters. Many acid‐sensitive functional groups, which cannot be tolerated when using a state‐of‐the‐art ruthenium catalyst, were compatible with manganese catalysis. This new process expands the scope of this transformation and highlights the uniqueness of earth‐abundant metal catalysis. The reaction could proceed with catalyst loadings at the parts per million (ppm) level with an exceptional turnover number of 72 350. This is the highest value yet reported for an earth‐abundant metal‐catalyzed AH reaction.