bluuebunny/crossref_metadata_2025 huggingface dataset:
Adicción a las Tecnologías: Adolescencia, familias y Trabajo Social. Revisión teórica del fenómeno
Authors: Roca Belijar Carlota
Published: January 2020

Las Tecnologías de la Información y Comunicación (TIC), se encuentran totalmente difundidas en nuestra sociedad actual, tanto es así que ya no es extraño ver a cualquier persona llevando y/o utilizando un móvil o un ordenador con observable asiduidad. Por otra parte, tampoco es menos cierto el hecho de que las mismas se constituyen como una de las herramientas de más utilidad hoy en día, muchas son las ventajas que estas presentan, permiten desde facilitar la comunicación o relaciones hasta comprar sin salir de casa, por ejemplo. Sin embargo, no todo en ellas es positivo, en los últimos tiempos se está constatando el nacimiento de un nuevo fenómeno que afecta especialmente a niños/as y/o adolescentes, y es que, son cada vez más frecuentes los casos en los que éstos desarrollan patrones de conducta nocivos o adictivos en relación con el uso de las TIC. Este hecho, hace que todo en la vida de dichos/as niños/as y/o adolescentes cambie de manera radical al verse afectados numerosos aspectos o ámbitos de la misma como por ejemplo, el familiar, uno de los contextos más damnificados al ser el más próximo o cercano. En base a esto, a lo largo de este artículo se realizará un recorrido por alguna de las cuestiones que giran en torno a una adicción a las TIC, haciendo especial mención a la perspectiva del Trabajo Social en relación con este tema.  

Information and Communication Technologies (ICT), are fully disseminated in our current society, so much so that it is no longer strange to see anyone carrying and/or using a mobile or a computer with observable assiduity. On the other hand, it is not less true fact that they are constituted as one of the most useful tools today, there are any advantages that they present, they allow from facilitating communication or relationships to buying without leaving home, for example. However, not everything in them is positive, in recent times the birth of a new phenomenon that especially affects children and/or adolescents is being verified, and that is, the cases in which these are increasingly frequent develop harmful or addictive behavior patterns in relation to the use of ICT. This fact, makes everything in the life of such children and/or adolescents change radically as many aspects or areas of it are affected, such as family, one of the most affected contexts to be the closer or closer. Based on this, throughout this article there will be a tour of some of the issues that revolve around an addiction to ICT, making special mention of the perspective of Social Work in relation this issue.
Una mirada al futuro próximo en la transformación de los cementerios desde la perspectiva de la Arquitectura Emocional
Authors: Martínez Vicente Mónica
Published: January 2020

Los cambios que se están produciendo en la sociedad actual también manifiestan nuevas necesidades en la manera de despedirnos y recordarnos, lo que afecta directamente a la arquitectura funeraria de tanatorios y sobre todo de cementerios. A través de la «arquitectura emocional» se puede intervenir en los cementerios existentes para mejorar la percepción que transmiten a los usuarios y naturalizar los procesos de pérdida. En las futuras ampliaciones o construcción de nuevas instalaciones y/o cementerios deben tenerse en cuenta todas estas cuestiones de la arquitectura que conecta con las personas.

The changes that are taking place in today's society also show new needs in the way we remind ourselves, which directly affects funerary architecture of funeral parloursand especially in cemeteries. Through the «emotional architecture» we can intervene in existing cemeteries to improve the perception which they transmit to users and thus naturalize loss processes. All these issues of the architecture that connects with the people must be taken into account in the future enlargements or construction of new facilities and/or cemeteries.
Culturas funerarias europeas
Authors: Schriewer Klaus , Martínez Cavero Pedro
Published: January 2020

Presentación del número 26 de Revista Murciana de Antropología sobre «Culturas funerarias europeas»
Gender and the Faculty Care Gap: “The Obvious Go-To Person” for Canadian University Students’ Personal Problems
Authors: Dengate Jennifer , Peter Tracey , Farenhorst Annemieke
Published: January 2020

A mixed methods analysis of Canadian natural sciences and engineering faculty’s workplace experiences revealed a gendered care gap with women reporting greater responsibility for students’ personal and mental health problems, including suicidal thoughts and behaviour, and sexual assault. Statistical results demonstrated that women were approached by a significantly greater number of students to discuss serious non-academic issues and experienced more stress as a result. A comparative qualitative analysis found faculty’s responses to students’ problems were informed by gendered cultural care expectations thatrequire women to be more supportive than men. However, female and male faculty’s care burden may also be exacerbated by institutional factors, including senior administrative positions, undergraduate class loads, and teaching courses with mental health-related content. As such, the care gap is relevant to understanding the extent to which gender inequality is embedded within the structure of universities.
Análise bibliométrica da produção científica sobre turismo de base comunitária de 2013 a 2018
Authors: Graciano Pollyanna Fraga , Holanda Luciana Araújo de
Published: January 2020

O Turismo de Base Comunitária é uma proposta para o planejamento e o desenvolvimento das localidades através da atividade turística, fundamentada nos conceitos de sustentabilidade e desenvolvimento sustentável, promovendo a emancipação social das comunidades por meio do protagonismo da população na autogestão de seus bens, serviços e ca-pital social, para assim atingir a melhoria da qualidade de vida de seus moradores e a conservação de seu patrimônio ambiental, histórico e cultural. Com o objetivo de compreender a produção científica, que ganhou espaço a partir de 1990, e identificar possíveis lacunas sobre tema, este artigo reúne Revisão Integrativa da Literatura (RIL) ao Estudo Bibliométrico (EB) para analisar uma amostra de 158 artigos em português, espanhol e inglês distribuídos por 64 periódicos. O estudo cumpriu as três principais leis da bibliometria: Lotka, Bradford e Zipf, indicando o TBC como uma temática em expansão e com produção pulverizada. Por fim, a síntese dos conhecimentos produzidos identificou como possíveis lacunas teóricas: governança e comercialização.
ПРОБЛЕМЫ ИММУНОДИАГНОСТИКИ ПРИ ТУБЕРКУЛЕЗЕ, "Вестник Центрального научно-исследовательского института туберкулеза"
Authors: Гергерт Владислав Яковлевич , Еремеев Владимир Витальевич , Лядова Ирина Владимировна , Авербах Михаил Михайлович , Эргешов Атаджан Эргешович
Published: January 2020

В обзоре рассматриваются вопросы иммунодиагностики при туберкулезном инфицировании и заболевании, причины наличия или отсутствия ответа макроорганизма в иммунологических тестах, связанные с индивидуальной чувствительностью к антигенам микобактерий, антигенной нагрузкой, генетически детерминированной резистентностью к заболеванию, тяжестью процесса.
МАРКЕРЫ НУТРИТИВНОЙ НЕДОСТАТОЧНОСТИ У БОЛЬНЫХ ТУБЕРКУЛЕЗОМ, СОЧЕТАННЫМ С ВИЧ-ИНФЕКЦИЕЙ, "Вестник Центрального научно-исследовательского института туберкулеза"
Authors: Герасимов Лев Николаевич , Абдуллаев Ризван Юсифович , Комиссарова Оксана Геннадьевна
Published: January 2020

Обследованы 347 больных туберкулезом (ТБ), которые были разделены на 2 группы. В первую группу вошли 224 пациента с ТБ, сочетанным с ВИЧ-инфекцией, во вторую - 123 больных туберкулезом без ВИЧ-инфекции. Нутритивный статус определяли по показателям индекса массы тела (ИМТ), содержанию транстиретина (ТТ), альбумина (А) и общего белка (ОБ) в сыворотке крови. Было установлено, что у больных обеих групп наблюдалась нутритивная недостаточность, о чем свидетельствовало снижение ИМТ, уровня альбумина и транстиретина. Однако выраженность нутритивной недостаточности была более значительна у пациентов с ТБ и ВИЧ-инфекцией, что документировалось более существенным снижением уровня ТТ и А. Выраженность белково-энергетической недостаточности организма у больных ТБ, сочетанным с ВИЧ-инфекцией, была взаимосвязана, с одной стороны, с особенностями течения туберкулезного процесса, а другой - с течением ВИЧ-инфекции. Наиболее значительное снижение нутритивного статуса наблюдалось у больных фиброзно-кавернозным ТБ легких, ТБ множественных локализаций, с распространенностью специфического процесса в легких более 2 долей, распадом в легочной ткани и бактериовыделением c широкой лекарственной устойчивостью (ШЛУ) микобактерий ТБ (МБТ). Было установлено, что наиболее выраженное снижение белково-энергетической обеспеченности организма выявляется при снижении количества CD4 клеток менее 0,35 х 10 /л и вирусной нагрузкой ВИЧ более 500 0 копий/мл.
КЛИНИЧЕСКИЙ ОПЫТ И УСПЕХИ В ОБЛАСТИ ПРИМЕНЕНИЯ КОНФОКАЛЬНОЙ ЛАЗЕРНОЙ ЭНДОМИКРОСКОПИИ ДЫХАТЕЛЬНЫХ ПУТЕЙ (ОБЗОР ЛИТЕРАТУРЫ И СОБСТВЕННЫЕ ДАННЫЕ), "Вестник Центрального научно-исследовательского института туберкулеза"
Authors: Данилевская Олеся Васильевна , Аверьянов Александр Вячеславович
Published: January 2020

Зондовая конфокальная лазерная эндомикроскопия (КЛЭМ) появилась в 2007 году и на сегодняшний день является уникальной технологией, позволяющей в режиме реального времени прижизненно визуализировать интраацинарные структуры. В данном обзоре описаны возможности КЛЭМ в диагностике различных заболеваний легких, представленные исходя из личного опыта авторов и данных других исследователей, занимающихся разработкой метода альвеолоскопии во всем мире. Главными достоинствами метода являются: возможность оценить внутриальвеолярные структуры с аутофлюоресценцией, содержащие эластические волокна, белки, липиды, фосфор или табачные смолы; потенциальное определение признаков неопластического процесса. Однако есть и ряд ограничений метода, сужающих возможности его применения в широкой клинической практике.
ВЛИЯНИЕ ЧЕЛОВЕЧЕСКОГО ИММУНОГЛОБУЛИНА НА ТЕЧЕНИЕ РАННЕГО ПОСЛЕОПЕРАЦИОННОГО ПЕРИОДА ПОСЛЕ ПНЕВМОНЭКТОМИИ И ЧАСТОТУ ОСЛОЖНЕНИЙ У БОЛЬНЫХ ПРОГРЕССИРУЮЩИМ ДЕСТРУКТИВНЫМ ТУБЕРКУЛЕЗОМ ЛЕГКИХ С МНОЖЕСТВЕННОЙ ЛЕКАРСТВЕННОЙ УСТОЙЧИВОСТЬЮ ВОЗБУДИТЕЛЯ, "Вестник Цен
Authors: Пенаги Сурхаб Ниджат Алиевич , Багиров Мамад Адилович , Можокина Галина Николаевна , Красникова Елена Вадимовна , Пенаги Рамиль Ниджат-Алиевич
Published: January 2020

Сорока пяти больным деструктивным туберкулезом (ТБ) легких с множественной лекарственной устойчивостью (МЛУ) возбудителя, перенесшим пульмонэктомию, в раннем послеоперационном периоде назначали человеческий иммуноглобулин (ЧИ) с целью профилактики ранних бронхолегочных осложнений. Группу сравнения составили 45 больных, которым в раннем послеоперационном периоде ЧИ не вводили. Послеоперационный период у пациентов основной группы протекал гладко, отмечалась быстрая реабилитация. Осложнения в виде эмпиемы плевральной полости без формирования свища в раннем послеоперационном периоде наблюдались у двух человек (4,4%), которым были успешно выполнены этапные операции торакостомии и торакомиопластики. У больных группы сравнения осложнения возникали достоверно чаще (28,9%, р < 0,01). Наибольший удельный вес среди осложнений пришелся на несостоятельность культи главного бронха и развитие эмпиемы плевры (46,7%), для устранения которых потребовались дополнительные операции. У 2 пациентов прогрессирование туберкулезного процесса в единственном легком привело к смерти. Летальным исходом в течение первой недели после операции закончилась послеоперационная пневмония в единственном легком у 3 из 4 больных. В результате 11,1% пациентов группы сравнения с наиболее тяжелыми осложнениями погибли в течение первого месяца после операции. Таким образом, применение ЧИ в раннем послеоперационном периоде после пневмонэктомии позволило в 6 раз снизить частоту осложнений и избежать летальных исходов.
ВЫЯВЛЕНИЕ МИКОБАКТЕРИЙ МЕТОДОМ МИКРОСКОПИИ ПРЕПАРАТОВ, ОКРАШЕННЫХ ПО ЦИЛЮ-НИЛЬСЕНУ Часть 1. Приготовление и окрашивание препаратов для микроскопии, "Вестник Центрального научно-исследовательского института туберкулеза"
Authors: Севастьянова Элина Викторовна , Ларионова Елена Евгеньевна , Андриевская Ирина Юрьевна
Published: January 2020

Изложен метод выявления микобактерий (МБ) с помощью микроскопического исследования препаратов, окрашенных по методу Циля-Нильсена. Описаны варианты приготовления препаратов для микроскопии из необработанной мокроты, осадка диагностического материала, а также из культуры Мб. Представлена методика окрашивания препаратов по Цилю-Нильсену. Проведен анализ возможных ошибок при приготовлении и окраске мазков.
Effect of Roasting Temperature and Duration on the Quality of Oil from Walnut (Plukenetia conophorum) Using Response Surface Methodology
Authors: Fatima A. Raji, , Rahman Akinoso
Published: January 2020

This study investigated the effect of heat treatment and duration on yield and qualities of Walnut (Plukenetia conophorum) oil. The experimental design was carried out using the central composite rotatable design (CCRD) of response surface methodology with a total of thirteen experimental runs. The process variables and their ranges were roasting temperature 87.57ºC to 172.43ºC and roasting duration 10 min to 46.21 min. Oil from each experimental run was extracted using Piteba screw oil expeller. The expressed oil yield was determined and the results revealed that the oil yield ranged from 33.87% to 30.67% for the maximum and minimum values which were achieved at temperatures and duration of 172.43% at 25 min and 87.57ºC at 25 min respectively. Optimum process condition was achieved at roasting temperature and duration of 160ºC and 40 min with two possible solutions of 0.82 desirability which gave oil yield (33.50%); peroxide value (7.8 MeqO2/g); colour (13.69 mg/L); free fatty acid (1.46%) and iodine value (136.82 mmol/100 g). The low free fatty acid and peroxide values in walnut oil is an indication of its overall quality thus its suitability as an alternative oil to supplement existing edible oils.
Nutritional Profile and Organoleptic Qualities of Milk Chocolate Incorporated with Different Spices
Authors: Aroyeun S. O. , Okunade A. F. , Obatoye A. O. , Olalekna M. A.
Published: January 2020

An innovative spicy chocolate was developed in this study by partial replacement of cocoa nibs with different selected spice powders of: Ginger (G11), Garlic (G12), Clove (C13), Cinnamon, (C14), Turmeric (T15), Aframomum danielli (A16), Aframomum melegueta (A17), Thyme (T18), Black Pepper (B19) and Clappertonia (C20). Milk chocolate without spices (C10) served as Control. The proximate compositions were carried out using standard methods. The Total Calorific values (TCV) was determined using the Atwater factors (physiological fuel values) of 4kcal, 4kcal and 9kcal per gram of carbohydrate, protein and fat respectively. The sensory evaluation was carried out by panel of tasters consisting of 13 males and 18 female staff of the Cocoa Research Institute of Nigeria who were used to consuming chocolates. The result showed significant differences in the proximate chemical compositions of the chocolates (p<0.05). Apart from black pepper with a An significantly lower protein and ash contents when compared to the control chocolate, all the other spices significantly caused an increase in percentage protein and ash  in  the control milk chocolate. The trend of protein increase is T18 > G11 > T15 > C20 =A17 > A16 > C14 > C13 > G12 > C10 > B19 > respectively. The range of values obtained for the proximate compositions were (%)The Total Calorific Value (TCV) also showed significant differences among all the samples at p<0.05 with the TCV of the control chocolate being the highest. The addition of spices contributed to acceptable tastes, aroma, flavor and general acceptability of milk chocolates. In Conclusion, this study showed that the incorporation of Spices in chocolate increased the protein and ash content of milk chocolate, the organoleptic acceptance while reducing the TCV values This is a desirable findings in view of the fear of high calorific values of Milk Chocolate which may predispose consumers to Obesity when consumed.in large quantities.
Towards A Sustainable Fire-free Environment in Kebbi State: Causes and People’s Behaviour in Fire Disasters
Authors: Ilori Alade E. , Magaji Rabiu A.
Published: January 2020

Fire disaster is accident that occur most frequently with different causes. It requires strong intervention for a sustainable fire-free environment. This study assessed causes and people’s behaviour in fire disasters towards a sustainable fire-free environment in Kebbi State, Nigeria. The study focused at identifying remote causes of fire disasters in Kebbi State, the people’s behaviour in/to fire situations using the state capital (Birnin Kebbi) as well as equipment available in the state fire service head-office towards a fire-free environment. Descriptive research approach was used. A sample size of 204 respondents (30 market traders, 144 occupants and 30 fire service personnel) obtained through Cochran 1963 sample size formula were randomly selected. Questionnaire and observation were used to collect data which were analyzed through descriptive statistics (frequency tables and percentages) and results were presented in charts. Results revealed that electrical fault/wiring, political reasons, negligence among others are the causes of fire disaster in the area with electrical fault/wiring as the remote cause. The behaviour of people towards building a sustainable fire-free environment shows people of the area do help one another in extinguishing fire whenever it strikes. Results also shows that lack of manpower and standard fire stations were the prominent challenges faced by the state fire service head-office in the state capital prompting incessant burning and resulting lives and property loss. Occupants of the area should always read and comply with safety guides of electrical appliances bought before use to avoid and prevent them from substandard gadgets that have ability of endangering their lives.
Development of a Solar Based Automatic Water Heating and Temperature-controlled Recirculating Aquaculture System
Authors: Tangka Julius K. , Yusifu Wirsiy F.
Published: January 2020

Recirculating aquaculture systems have proven very successful in resolving problems relating to water shortages for fish production and increased yield as the stocking density is important. These systems however consumed much energy in running pumps and heating of water since temperatures play a critical role in fish growth. The main objective of this study is to contribute in putting in place a stable automatic temperature-controlled recirculating aquaculture system capable of using water and energy in an efficient manner. The aim is to develop a system that can use 1000 L of water and grow fish to maturity. The system consisted of a 1000 L capacity tank, a mechanical filter, a bio rock filter, a de-nitrification tank with water hyacinth, an aeration system, a 12 V solar pump, a solar water heating system, and computerized automatic controls using the Arduino microprocessor. Everything was powered by 100 Watts solar module connected through a charge controller to a 200 AH Battery. One hundred catfish fingerlings were raised in a period of 8 months. Water from the fish tank move by gravity to the mechanical filter before being pumped to the bio rock filter. From the bio rock filter, the water moves to the de-nitrification tank. From the de-nitrification tank the automatic control system either sends it back to the fish tank or directs it through the solar water heating if tank temperatures are below 25°C. In order to assess the performance of the system, physical and chemical water parameters were measured. These included the total dissolved solids (TDS), pH, electrical conductivity (EC) temperature, dissolve oxygen, ammonia, nitrite, and nitrates. Results showed that the average daily weight gain of catfish fingerlings was 0.39±0.28 g and that the physical and chemical water quality parameters were at optimum levels for fish growth. It was concluded that such a system can enable farmers to grow fish to maturity in a region with limited water and energy resources.
Affective Neuroscience and Adult Education
Authors: Taylor Kathleen
Published: December 2024

The expanding field of affective neuroscience is redefining the role of emotions in cognition, reasoning, and judgment. This contradicts long‐standing assumptions about cognition that consider emotions antithetical to learning. Emotions arose early in human brain development as essential to survival by directing the embodied brain toward life‐sustaining and away from life‐threatening environments. Metaphorical language, which emerges from embodied experience, is also necessary for thinking, reasoning, and learning. The brain's right hemisphere (RH) is the primary site for understanding figurative and symbolic language. Educational environments emphasize the left hemisphere's capacity for syntactic language and direct, linear thought. Though the RH has a more comprehensive view of reality, its contributions may be ignored or dismissed because it communicates metaphorically and symbolically. Drawing on elements of affective neuroscience, embodied emotions, and hemispheric difference may provide educators with new awareness in reconstructing adult learning environments with the embodied brain in mind.
Enhancing Power Conversion Efficiency of Perovskite Solar Cells Through Machine Learning Guided Experimental Strategies
Authors: Yang Antai , Sun Yonggui , Zhang Jingzi , Wang Fei , Zhong Chengquan , Yang Chen , Hu Hanlin , Liu Jiakai , Lin Xi
Published: December 2024

Predicting the power conversion efficiency (PCE) using machine learning (ML) can effectively accelerate the experimental process of perovskite solar cells (PSCs). In this study, a high‐quality dataset containing 2079 experimental PSCs is established to predict PCE values using an accurate ML model, achieving an impressive coefficient of determination (R2) value of 0.76. In the 12 validation experiments with PSCs, the average absolute error between the observed and predicted PCE values is only 1.6%. Leveraging the recommended improvement solutions from the ML model, the device's PCE to 25.01% in experimental PSCs is successfully enhanced, thus truly realizing the objective of machine learning‐guided experiments. In addition, by improving the PCE of specific devices, the predicted value can reach 28.19%. The ML model has provided feasible strategies for experimentally improving the PCE of PSCs, which play a crucial role in achieving PCE breakthroughs.
Recent Progress and Challenges of Li‐Rich Mn‐Based Cathode Materials for Solid‐State Lithium‐Ion Batteries
Authors: Huang Qiqiang , Liu Jinquan , Chen Xinman , Zhang Peng , Lu Languang , Ren Dongsheng , Ouyang Minggao , Liu Xiang
Published: December 2024

Li‐rich Mn‐based (LRM) cathode materials, characterized by their high specific capacity (>250 mAh g−¹) and cost‐effectiveness, represent promising candidates for next‐generation lithium‐ion batteries. However, their commercial application is hindered by rapid capacity degradation and voltage fading, which can be attributed to transition metal migration, lattice oxygen release, and the toxicity of Mn ions to the anode solid electrolyte interphase (SEI). Recently, the application of LRM cathode in all‐solid‐state batteries (ASSBs) has garnered significant interest, as this approach eliminates the liquid electrolyte, thereby suppressing transition metal crosstalk and solid–liquid interfacial side reactions. This review first examines the historical development, crystal structure, and mechanisms underlying the high capacity of LRM cathode materials. It then introduces the current challenges facing LRM cathode and the associated degradation mechanisms and proposes solutions to these issues. Additionally, it summarizes recent research on LRM materials in ASSBs and suggests strategies for improvement. Finally, the review discusses future research directions for LRM cathode materials, including optimized material design, bulk doping, surface coating, developing novel solid electrolytes, and interface engineering. This review aims to provide further insights and new perspectives on applying LRM cathode materials in ASSBs.
A Smart Slippery Surface with Reversible Dynamic Temperature Responsiveness for Long‐Term Controllable Anti‐Icing
Authors: Huai Jiru , Zhang Jiaxuan , Wang Peng , An Wenjie , Zhao Xiang , Zhang Zhen , Wang Wenliang , Duan Wei , Yue Ying
Published: December 2024

Recently, slippery liquid‐infused porous surface (SLIPS) is widely utilized for anti‐icing. Nevertheless, a major challenge hindering the practical applications of SLIPS is the depletion of lubricating oil, significantly deteriorating its deicing performance. Given that super‐slippery effects are not required during most non‐icing periods, this research introduces a novel dynamic wettability‐adjustable SLIPS anti‐icing coating inspired by the nepenthes. This coating‐comprising modified diatomaceous earth and soft silicone rubber‐releases lubricating oil only when temperatures fall below −2 °C, thus exhibiting super‐slippery characteristics and effectively preventing icing. The porous modified diatomaceous earth retains lubricating oil for prolonged periods and facilitates its controlled release under external forces. The high elasticity and strength of the soft silicone rubber endow the coating with thermal expansion and contraction capabilities, enabling the active absorption and release of lubricating fluid in response to temperature variations. This coating, prepared using a straightforward strategy, demonstrates an ice adhesion strength and an oil loss rate of less than 23 kPa and 13%, respectively, after 50 icing/de‐icing cycles. These findings highlight the remarkable performance of the coating, providing valuable insights for achieving long‐term anti‐icing on the external surfaces of equipment in extreme working conditions.
Unveiling the Origin of the Strengthening Mechanism in a Novel Precious Metal Multi‐Principal Elements Alloy
Authors: Zhou Xuan , Ge Hualong , Xiong Kai , He Junjie , Zhang Shunmeng , Fu Li , Tan Zhilong , Wu Xiaofei , Li Xuming , Wu Haijun , Guo Junmei , Mao Yong
Published: December 2024

Precious metal electrical contact materials are pivotal in microelectronic devices due to their excellent chemical stability and electrical properties. Their practical application is hindered by the strength, contact resistance, and high cost. Multi‐principal elements alloys (MPEAs) provide the possibility to develop cost‐effective materials with enhanced mechanical properties. To address this, a novel precious metal MPEA, PdAgCuAuPtZn alloy, is designed, which exhibits significant solid solution strengthening and aging strengthening effects. The ultimate tensile strength increases from 747 MPa in the solution state to 1126 MPa in the aged state, while resistivity remains low. This study presents the first systematic investigation into the strengthening mechanisms of precious metal MPEAs using nanoindentation technology. These findings indicate that the aging strengthening of the alloy is attributed to spinodal decomposition (SD) and chemical short‐range order (CSRO) in the matrix. Furthermore, the precipitation structure with Cu‐rich and Ag‐rich phases gradually replaces the matrix, primarily accounting for aging softening. Additionally, it is discovered that precipitation structure can be strengthened by CSRO formed in the Cu‐rich phase, thus providing an innovative strengthening in PdAgCuAuPtZn alloy. These results will be beneficial to both deeply understanding the aging behaviors of PdAgCuAuPtZn alloys and designing high‐performance precious metal MPEAs.
AI‐Guided Inverse Design and Discovery of Recyclable Vitrimeric Polymers
Authors: Zheng Yiwen , Thakolkaran Prakash , Biswal Agni K. , Smith Jake A. , Lu Ziheng , Zheng Shuxin , Nguyen Bichlien H. , Kumar Siddhant , Vashisth Aniruddh
Published: December 2024

Vitrimer is a new, exciting class of sustainable polymers with healing abilities due to their dynamic covalent adaptive networks. However, a limited choice of constituent molecules restricts their property space and potential applications. To overcome this challenge, an innovative approach coupling molecular dynamics (MD) simulations and a novel graph variational autoencoder (VAE) model for inverse design of vitrimer chemistries with desired glass transition temperature (Tg) is presented. The first diverse vitrimer dataset of one million chemistries is curated and Tg for 8,424 of them is calculated by high‐throughput MD simulations calibrated by a Gaussian process model. The proposed VAE employs dual graph encoders and a latent dimension overlapping scheme which allows for individual representation of multi‐component vitrimers. High accuracy and efficiency of the framework are demonstrated by discovering novel vitrimers with desirable Tg beyond the training regime. To validate the effectiveness of the framework in experiments, vitrimer chemistries are generated with a target Tg = 323 K. By incorporating chemical intuition, a novel vitrimer with Tg of 311–317 K is synthesized, experimentally demonstrating healability and flowability. The proposed framework offers an exciting tool for polymer chemists to design and synthesize novel, sustainable polymers for various applications.
Thermosensitive Hydrogel Integrated with Bimetallic Nano‐Enzymes for Modulating the Microenvironment in Diabetic Wound Beds
Authors: Zhang Chuwei , Zhang Xiaoyi , Li Fei , Li Bo , Zhang Mengnan , Li Wanqian , Zhuge Pan , Yao Jingye , Zhang Yi , Chen Shixuan , Fang Yongjin , Cai Chao
Published: December 2024

Effective regulation and reconstruction of the microenvironment are critical for the regeneration of chronic wounds. Diabetic wounds, in particular, pose a significant clinical challenge due to increased oxidative stress and dysfunctional healing processes. In this study, a novel therapeutic strategy is developed using 3D copper‐magnesium bimetallic antioxidant nano‐enzymes (Cu/Mg‐MOF) to mitigate reactive oxygen species (ROS) and restore redox balance through electron transfer. To optimize delivery, a thermo‐sensitive hydrogel composed of chitosan (CS) and ε‐polylysine (PL) is designed, serving as an efficient carrier for the nano‐enzymes. This Cu/Mg‐MOF@CS/PL hydrogel exhibits excellent physical properties, including injectability, softness, and biocompatibility, making it ideal for application in diabetic wounds. In a diabetic wound model, treatment with Cu/Mg‐MOF@CS/PL hydrogel significantly accelerated wound healing, with a closure rate of 90.6% by day 14, compared to just 55.4% in the untreated group. The hydrogel effectively promoted key aspects of wound healing, such as collagen deposition, re‐epithelialization, angiogenesis, and immunomodulation. These findings underscore the potential of the Cu/Mg‐MOF@CS/PL hydrogel as a promising therapeutic system for enhancing the healing of diabetic wounds.
In Situ Electron Tomography Insights into the Curvature Effect of a Concave Surface on Fe Single Atoms for Durable Oxygen Reaction
Authors: Li Jun‐Kang , Zhao Haobo , Zhang Yang , Ma Jing‐Jing , Wang Fen‐Fen , Zhao Shu‐Na , Li Jun , Zang Shuang‐Quan
Published: December 2024

Curvature‐induced interfacial electric field effects and local strain engineering offer a powerful approach for optimizing the intrinsic catalytic activity of single‐atom catalysts (SACs). Investigations into the surface curvature on SACs are still ongoing, and the impact of the concave surface is often overlooked. In this work, theoretical calculations indicate that curved surfaces, particularly those with concavity, can optimize the electronic structures of single Fe sites and facilitate the reductive release of *OH. A carbon sphere featuring uniformly oriented channels and a chiral multi‐shelled carbon hollow nanosphere are selected as carbon matrices due to their accessible concave and/or convex surfaces. After loading Fe species, the resulting catalysts with Fe SA in curved surfaces exhibit excellent oxygen reduction reaction activity (E1/2 = ≈0.89 V), strong methanol tolerance, and favorable long‐term stability. Impressively, a solid‐state flexible Zn–air battery based on this catalyst exhibits a remarkable durability over 40 h with a high peak power density of 122.1 mW cm−2 and excellent charge–discharge performance at different bending angles. This work offers in‐depth insights into the rational design of carbon supports with highly curved surfaces, offering new opportunities for the microenvironmental regulation of SACs at the atomic level.
Bifunctional Design of Ferroelectric‐Order and Band‐Engineering in Cu:KTN Crystal for Extended Self‐Powered Photoelectric Response
Authors: Wang Yaqian , Wu Yabo , Liang Fei , Wang Xuping , Yu Haohai , Zhang Huaijin , Wu Yicheng
Published: December 2024

Photoelectric conversion in ferroelectric crystals can support many important applications in modern on‐chip technology, but suffering from two problems, low responsive current and narrow responsive range. Especially, wide‐gap ferroelectric oxides are only active at short‐wavelength ultraviolet region with weak photocurrent at nanoampere levels. Here, a bifunctional design strategy of ferroelectric‐order and electronic‐band to improve the photocurrent and extend the responsive range simultaneously, is proposed. In a Cu‐doped KTa1−xNbxO3 (KTN) perovskite crystal, a conductive channel is constructed by “head‐to‐head” ferroelectric domains, associated with the emergence of micrometer‐scale supercells. In addition, the introduction of Cu+ ion can induce defect levels, thus extending the responsive range beyond the inherent absorption of pure KTN. Through rational device optimization, a record self‐powered responsivity of 5.23 mA W−1 is realized in Cu:KTN photodetector, which is two orders of magnitude higher than undoped KTN crystal. The temperature‐dependent light diffraction and photocurrent show that the ferroelectric‐order is dominated in this photoresponse behavior. Moreover, Cu:KTN detector is active in the broadband range from 390 to 1030 nm, covering ultraviolet, visible, and near‐infrared regions. This work provides an effective method for the design of next‐generation self‐powered photodetectors with ultrahigh responsivity and ultrawide responsive range.
GeTe/Sb2Te3 Super‐Lattices: Impact of Atomic Structure on the RESET Current of Phase‐Change Memory Devices
Authors: Térébénec Damien , Hippert Françoise , Bernier Nicolas , Castellani Niccolo , Noé Pierre
Published: December 2024

Phase change memories (PCMs) are at the heart of modern memory technology, offering multi‐level storage, fast read/write operations, and non‐volatility, bridging the gap between volatile DRAM and non‐volatile Flash. The reversible transition between amorphous and crystalline states of phase‐change materials such as GeTe or Ge2Sb2Te5 is at the basis of PCM devices. Despite their importance, PCM devices face challenges including high power consumption during the RESET operation. Current research efforts focus on improving device architecture and exploring alternative phase‐change materials such as GeTe/Sb2Te3 super‐lattices (SLs), for which a reduced programming power consumption is observed compared with standard PCMs. Herein, by combining X‐ray diffraction and scanning transmission electron microscopy imaging of SL thin films with the study of the same SL in PCM devices, it is shown that it is possible to significantly decrease RESET energy of the device, without modifying the SL composition, by reducing the amount of structural defects through annealing treatment. The best device properties are obtained after transforming the SL into a defect‐free, highly out‐of‐plane oriented rhombohedral phase. These results offer a promising avenue for further improving the performance of SL‐based PCM devices through structural optimization.
Tunneling Dielectric Thickness‐Dependent Behaviors in Transistors Based on Sandwiched Small Molecule and Insulating Layer Structures
Authors: Lee Dong Hyun , Jeon Yunchae , Choi Junhwan , Yoo Hocheon
Published: December 2024

This work demonstrates the floating gate devices featuring a small molecule‐insulator‐small molecule‐insulator sandwiched structure, where the versatile electrical characteristics can be achieved depending on the thickness of the intermediate parylene tunneling dielectric layer (TDL). For the thin parylene layer of 15 nm (parallel DNTT channel transistor), channel also forms in the lower DNTT layer, allowing hole carriers to tunnel through the parylene TDL. The parallel DNTT channel transistor exhibits electrical characteristics similar to a conventional DNTT transistor with the increased contact resistance due to the presence of the intermediate parylene layer. When the parylene TDL is slightly thicker to be 45 nm, negative differential transconductance followed by current saturation behavior is observed, due to tunneling through the parylene TDL. Finally, photomemory is demonstrated with the sufficiently thick parylene layer (≈80 nm), where hole carriers injected from the electrode cannot tunnel through the parylene TDL, allowing the lower DNTT layer to act as a floating gate for the photogenerated charge carriers. This photomemory shows programmability under the light illumination with the specific wavelength as well as the robust retention and endurance characteristics. Furthermore, the photomemory has been successfully implemented on flexible paper substrates.
The decrease in zinc‐finger E‐box‐binding homeobox‐1 could accelerate steroid‐induced osteonecrosis of the femoral head by repressing type‐H vessel formation via Wnt/β‐catenin pathway
Authors: Zhang Guangyang , Cai Yuanqing , Liang Jialin , Jing Zhaopu , Wei Wang , Lv Leifeng , Dang Xiaoqian , Song Qichun
Published: December 2024

Background

Zinc‐finger E‐box‐binding homeobox‐1 (ZEB1) is predominantly found in type‐H vessels. However, the roles of ZEB1 and type‐H vessels in steroid‐induced osteonecrosis of the femoral head (SONFH) are unclear.

Methods

Human femoral heads were collected to detect the expression of ZEB1 and the levels of type‐H vessels. Then, the SONFH model was developed by injecting C57BL/6 mice with lipopolysaccharide and methylprednisolone. Micro‐computed tomography, angiography, double calcein labeling, immunofluorescence, immunohistochemistry, quantitative real‐time polymerase chain reaction, and Western blotting were performed to detect the expression of ZEB1, the Wnt/β‐catenin pathway, type‐H vessels, and the extent to which ZEB1 mediates angiogenesis and osteogenesis. Human umbilical vein endothelial cells were also used to explore the relationship between ZEB1 and the Wnt/β‐catenin pathway.

Results

We found that ZEB1 expression and the formation of type‐H vessels decreased in SONFH patients and in a mouse model. The number of vascular endothelial growth factors in the femoral heads also decreased. Moreover, the bone mineral density, trabecular number, mineral apposition rate, and expression of genes related to osteogenesis decreased. After ZEB1 knockdown, angiogenesis and osteogenesis decreased. However, the numbers of type‐H vessels and the extent of angiogenesis and osteogenesis improved after activation of the Wnt/β‐catenin pathway.

Conclusions

The ZEB1 expression decreased in SONFH, causing a decrease in type‐H vessel, and it mediated angiogenesis and osteogenesis by regulating the Wnt/β‐catenin pathway, ultimately accelerating the process of SONFH.
Self‐Immolative Polymers Derived from Renewable Resources via Thiol–Ene Chemistry**
Authors: Deng Zhengyu , Gillies Elizabeth R.
Published: December 2024

The development of polymers from renewable resources is a promising approach to reduce reliance on petrochemicals. In addition, depolymerization is attracting significant attention for the breakdown of polymers at their end‐of‐life or to achieve specific stimuli‐responsive functions. However, the design of polymers incorporating both of these features remains a challenge. Herein, we report a new class of self‐immolative polymers based on lignin‐derived aldehydes via a simple thiol‐ene polymerization. These self‐immolative polymers undergo cascade degradation in response to specific stimuli through alternating 1,6‐elimination and cyclization reactions. The two methoxy substituents on the syringaldehyde monomer accelerated the desired depolymerization reaction, while enhancing stability against undesired backbone hydrolysis. Moreover, diverse responsive end‐caps could be introduced through post‐polymerization functionalization from a single polymer precursor.
Hydroalkylation of Vinylarenes by Transition‐Metal‐Free In Situ Generation of Benzylic Nucleophiles Using Tetramethyldisiloxane and Potassium tert‐Butoxide
Authors: Onge Piers St. , Nugraha Hana , Newman Stephen G.
Published: December 2024

Hydrosilanes and Lewis bases are known to promote various reductive defunctionalizations, rearrangements, and silylation reactions, facilitated by enigmatic silicon/Lewis base‐derived reactive intermediates. Despite the wide variety of transformations enabled by this reagent combination, no examples of intermolecular C(sp3)−C(sp3) forming reactions have been reported. In this work, we've identified 1,1,3,3‐tetramethyldisiloxane (TMDSO) and KOtBu as a unique reagent combination capable of generating benzylic nucleophiles in situ from styrene derivatives, which can subsequently react with alkyl halides to give a new C(sp3)−C(sp3) linkage via formal hydroalkylation. Mechanistic experiments suggest that the reaction proceeds through a key hydrogen atom transfer (HAT) step from a hydrosilane reducing agent to styrene, affording a benzylic radical that undergoes reductive radical polar crossover (RRPC) and subsequent SN2 alkylation.
Chemical Upcycling of Thermoplastics Towards Thermosets Based on Dynamic Dimethylglyoxime‐Urethane Moiety
Authors: Sun Qiao , Liu Ling , Zhang Jianye , Chang Xiaohua , Chen Jianwen , Liu Zenghe , Zhu Yutian
Published: December 2024

Huge annual consumption of thermoplastics results in the generation of large amounts of waste after their service life. Currently, the most popular recycling method based on mechanically melt‐reprocessing deteriorates the material performance and is economically unattractive, which makes it unviable to be implemented in large scale. Herein, we present a chemical upcycling strategy that can transform dimethylglyoxime‐urethane based thermoplastic waste into thermoset product with superior mechanical properties and higher economic values than the initial one. It is found that the dimethylglyoxime‐urethane moiety has dynamic nature, endowing the material with open‐loop upcycling ability. By removing the dimethylglyoxime segment via a simple sublimation process, the material structure is transformed from linear molecular into crosslinked network. More interestingly, the transformation is reversible, and the regenerated crosslinked network can be transformed back to linear molecule by returning the removed dimethylglyoxime segment to the material, which means the upcycled product can be recycled again after its service life. Our linear/crosslinked transformation strategy provide a new option for recycling thermoplastic waste.
Solvent‐Dependent Divergent Cyclization of Bicyclo[1.1.0]butanes
Authors: Zhang Fuhao , Dutta Subhabrata , Petti Alessia , Rana Debanjan , Daniliuc Constantin G. , Glorius Frank
Published: December 2024

Bicyclo[1.1.0]butanes (BCBs) have recently garnered significant research interest as versatile precursors for synthesizing potential [n.1.1] bioisosteres and multi‐functionalized cyclobutanes in a straightforward and atom‐economical manner. Here, we report a solvent‐dependent divergent cyclization of BCBs that provides highly diastereospecific decorated cyclobutanes and oxygen‐containing bicyclo[3.1.1]heptanes (BCHeps), which serve as bioisosteres of meta‐substituted arenes. Additionally, an unprecedented 1,2‐difunctionalization reaction mode for BCBs was explored, thus expanding the chemical space of arene bioisosteres and highly functionalized cyclobutanes.
Copper‐Catalyzed Enantioselective Skeletal Editing through a Formal Nitrogen Insertion into Indoles to Synthesize Atropisomeric Aminoaryl Quinoxalines
Authors: Zhang Xu , Zhang Jin‐Qi , Sun Ze‐Hua , Shan Hui‐Mei , Su Jun‐Cheng , Ma Xiao‐Pan , Su Gui‐Fa , Xu Li‐Ping , Mo Dong‐Liang
Published: December 2024

Skeletal editing represents an attractive strategy for adding complexity to a given molecular scaffold in chemical synthesis. Isodesmic reactions provide a complementary skeletal editing approach for the redistribution of chemical bonds in chemical synthesis. However, catalytic enantioselective isodesmic reaction is extremely scarce and enantioselective isodesmic reaction to synthesize atropisomeric compounds is unknown. Herein, we report a facile method to synthesize axially chiral aminoaryl quinoxalines through Cu(I)‐catalyzed dearomatization and sequential chiral phosphoric acid (CPA) catalyzed enantioselective isodesmic C−N bond formation and cleavage from indoles and 1,2‐diaminoarenes under mild reaction conditions. In this process, the five‐membered ring of the indole scaffold was broken and a novel quinoxaline skeleton was constructed. This method allows the practical and atom‐economical synthesis of valuable axially chiral aminoaryl quinoxalines in high yields (up to 95 %) and generally excellent enantioselectivities (up to 99 % ee). Notably, this novel type of quinoxaline atropisomers has promising applications in developing axially chiral ligand in asymmetric catalysis. This strategy represents the first example of CPA‐catalyzed enantioselective isodesmic reaction to form axially chiral compounds.
New Thermoplastic Elastomers based on Ethylene‐Butadiene‐Rubber (EBR) by Switching from Anionic to Coordinative Chain Transfer Polymerization
Authors: Alioui Samy , Langlais Marvin , Ngo Robert , Habhab Karima , Dronet Séverin , Jean‐Baptiste‐dit‐Dominique François , Albertini David , D'Agosto Franck , Boisson Christophe , Montarnal Damien
Published: December 2024

Olefin triblock copolymers based on glassy polystyrene (PS), ethylene butadiene rubber (EBR) and highly crystalline polyethylene (PE) segments were prepared for the first time using a switch strategy from anionic polymerization to coordinative chain transfer (co)polymerization (CCT(co)P). PS chains obtained by anionic polymerization were transmetalated with mesitylmagnesium bromide (BrMgMes) to act as macromolecular chain transfer agents (macro‐CTA, PS‐MgMes) in the CCTcoP of ethylene and butadiene using {Me2Si(C13H8)2Nd(BH4)2Li(THF)}2 complex (1). Further chain extension by CCTP using pure ethylene in the monomer feed afforded well‐defined PS‐b‐EBR‐b‐PE triblock copolymers. The structural, rheological and mechanical properties of these materials demonstrate excellent balance between properties and easy processability at moderate temperatures (>150 °C). We demonstrate that such triblock copolymers behave effectively as low‐viscosity PS‐b‐EBR diblock copolymers above the melting point of PE domains and high performance thermoplastic elastomers (TPEs) upon crystallization of PE segments.