bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytoplasmic SIRT1 promotes paclitaxel resistance in ovarian carcinoma through increased formation and survival of polyploid giant cancer cells
Authors: Xu Hong , Zeng Shujun , Wang Yingmei , Yang Tong , Wang Minmin , Li Xuan , He Yejun , Peng Xin , Li Xia , Qiao Qing , Zhang Jing
Published: August 2023

Therapeutic resistance is a notable cause of death in patients with ovarian carcinoma. Polyploid giant cancer cells (PGCCs), commonly arising in tumor tissues following chemotherapy, have recently been considered to contribute to drug resistance. As a type III deacetylase, Sirtuin1 (SIRT1) plays essential roles in the cell cycle, cellular senescence, and drug resistance. Accumulating evidence has suggested that alteration in its subcellular localization via nucleocytoplasmic shuttling is a critical process influencing the functions of SIRT1. However, the roles of SIRT1 subcellular localization in PGCC formation and subsequent senescence escape remain unclear. In this study, we compared the differences in the polyploid cell population and senescence state of PGCCs following paclitaxel treatment between tumor cells overexpressing wild‐type SIRT1 (WT SIRT1) and those expressing nuclear localization sequence (NLS)‐mutated SIRT1 (SIRT1NLSmt). We investigated the involvement of cytoplasmic SIRT1 in biological processes and signaling pathways, including the cell cycle and cellular senescence, in ovarian carcinoma cells' response to paclitaxel treatment. We found that the SIRT1NLSmt tumor cell population contained more polyploid cells and fewer senescent PGCCs than the SIRT1‐overexpressing tumor cell population. Comparative proteomic analyses using co‐immunoprecipitation (Co‐IP) combined with liquid chromatography–mass spectrometry (LC‐MS)/MS showed the differences in the differentially expressed proteins related to PGCC formation, cell growth, and death, including CDK1 and CDK2, between SIRT1NLSmt and SIRT1 cells or PGCCs. Our results suggested that ovarian carcinoma cells utilize polyploidy formation as a survival mechanism during exposure to paclitaxel‐based treatment via the effect of cytoplasmic SIRT1 on PGCC formation and survival, thereby boosting paclitaxel resistance. © 2023 The Pathological Society of Great Britain and Ireland.
A systematic molecular dynamics study of the thermal conductivities of polyetherimide/graphene nanocomposites using response surface methodology
Authors: Mansourian‐Tabaei Mohammad , Jiang Shan , Alkhateb Hunain , Lopez Alexander M. , Al‐Ostaz Ahmed , Nouranian Sasan
Published: August 2023

In this work, an I‐optimal response surface model was used to systematically investigate the effects of graphene (Gr) content (Factor A; 0–10 wt%), temperature (Factor B; 0–200°C), and Gr layer structure (Factor C; monolayer versus five‐layer) on the thermal conductivities of PEI/Gr nanocomposites, which were determined using reverse non‐equilibrium molecular dynamics (RNEMD) simulation with the Müller‐Plathe algorithm. Based on a reduced quadratic model that was fit to the data, the effect of Factor A on thermal conductivity was found to be more pronounced for the PEI/Gr nanocomposite with the five‐layer Gr structure. Moreover, Factor B had expectedly the largest effect on thermal conductivity, followed by Factor C. However, these two factors were involved in significant interactions with Factor A. Based on numerical optimizations, the predicted thermal conductivities of the PEI/Gr nanocomposites varied from 0.057 (minimum) to 0.174 W m−1 K−1 (maximum). Overall, the maximum thermal conductivity of the PEI/Gr nanocomposite may be obtained at any given temperature in the range of 0–200°C by the addition of multi‐layer Gr (a cheaper alternative to monolayer Gr) at a content of 10 wt%. For example, the addition of 10 wt% five‐layer Gr to PEI at room temperature (25°) results yields an increase in its thermal conductivity of about 30%. Also, going from 0 to 100°C, an increase of about 76% is predicted for the thermal conductivity of the PEI/Gr nanocomposite containing 10 wt% five‐layer Gr. The results of this study shed light on the interactions between the three investigated factors.

Highlights

Thermal conductivities of polyetherimide/graphene (PEI/Gr) nanocomposites simulated.

Graphene (Gr) content, temperature, and Gr layer structure affected the thermal behavior.

Response surface methodology (RSM) aided in the identification of factorial interactions.

Numerical optimization of the thermal conductivities enabled by a predictive model.
Boron doped graphitic carbon nitride (BN‐g‐C3N4) and palm flower ash reinforced pyrimidinone core‐based polybenzoxazine composites for low‐k and high‐k applications
Authors: Appasamy Subasri , Kuppusamy Arunachalam , Arumugam Hariharan , Krishnasamy Balaji , Muthukaruppan Alagar
Published: August 2023

The present work provides a facile process route for the syntheses of pyrimidinone‐based benzoxazines by using stoichiometric quantities of pyrimidinone bisphenol (PBU) and paraformaldehyde, which are separately reacted with various types of amines under suitable experimental conditions. The molecular structure, curing characteristics, thermostability, hydrophobic behavior, and dielectric properties were analyzed using appropriate analytical methods. The polymerization temperature (Tp) of monomers such as PBU‐oda, PBU‐cha, PBU‐ffa, PBU‐a, and PBU‐fa was determined by differential scanning calorimetry (DSC), and the Tp values were noted at 205, 198, 203, 218, and 240°C, respectively. The percentage carbon residue at 850°C for poly(PBU‐oda), poly(PBU‐cha), poly(PBU‐ffa), poly(PBU‐a), and poly(PBU‐fa) were analyzed using thermogravimetric analysis (TGA). The water interface angle values for poly(PBU‐oda), poly(PBU‐cha), poly(PBU‐ffa), poly(PBU‐a), and poly(PBU‐fa) was found to be 141°, 134°, 142°, 136°, and 142°, respectively. The results from the dielectric studies indicate that the benzoxazines (PBU‐ffa and PBU‐a) composites reinforced with palm flower silica (PF‐SiO2) and boron nitride‐g‐C3N4 (BN‐g‐C3N4) were found to be suitable for low and high dielectric applications. From these diverse studies, it can be determined that pyrimidinone‐based benzoxazines to be utilized as high‐performance products in the form of encapsulants, potting agents, and composites for automotive and microprocessor applications.

Highlights

Pyrimidinone core bisphenol has developed through the efficient method.

New pyrimidinone core bisphenol based benzoxazine resins have been developed.

BN‐g‐C3N4 filled polybenzoxazine composites have prepared for high‐k applications.

Palm flower ash filled polybenzoxazine composites have prepared low‐k applications.

Thermal and morphological behavior of composites were studied.
Chlorine‐doped perovskite materials for highly efficient perovskite solar cell design offering an efficiency of nearly 29%
Authors: Bhattarai Sagar , Pandey Rahul , Madan Jaya , Ansari Mohd Zahid , Hossain M. Khalid , Amami Mongi , Ahammad Shaik Hasane , Rashed Ahmed Nabih Zaki
Published: August 2023

The new form of renewable energy attracts enormous attention from researchers for its immense importance and impact on our daily life. A fossil energy is a non‐renewable source that will end shortly because of its immense use in houses and industries. Among the renewable sources, solar cells based on perovskite (PVK) materials exponentially increase their efficiency from 3.8% to 25.8% rapidly in a diminutive period of time. In the present study, doped and undoped PVK layers (MAPbI3, MAPb[I1‐xClx]3) are considered and optimized for solar cell application by using the SCAPS‐1D device simulator. A detailed investigation is done in terms of PVK absorber layer (PAL) thickness variation with different electron and hole transport layers, temperature, and bulk defect density to optimize the device performance. The MAPb(I1‐xClx)3‐based device delivered the highest conversion efficiency of ~29% with JSC of 25.59 mA/cm2, VOC of 1.348 Volt, and an FF of about 83.68%. Results reported in this work may pave the way for the development of advanced high‐efficiency PVK solar cells.
The psychosocial experiences of head and neck cancer caregivers following (chemo)radiotherapy: A systematic qualitative review and narrative synthesis
Authors: Matthews Sara , Brett Jo , Ramluggun Pras , Watson Eila
Published: August 2023

Objective

Oropharyngeal cancer, a type of head and neck cancer (HNC), the incidence of which is increasing, often affects younger patients than traditional HNC, having distinct psychosocial consequences. Treatment side effects mean many rely on informal caregivers following (chemo)radiotherapy. The purpose of this review was to describe current understanding of the psychosocial experiences of these caregivers in the post‐treatment phase.

Methods

A systematic search for relevant studies between January 2010 and October 2022 in three electronic databases (CINAHL, MEDLINE and PsycINFO) was followed by citation searching. Inclusion criteria were developed to ensure studies explored caregivers' experiences during the post‐treatment phase following oropharyngeal cancer (chemo)radiotherapy. Thematic analysis informed by the ‘Cancer Family Caregiving Experience Model’, identified stressors, appraisals and responses. Themes evolved through the synthesis of recurrent concepts across the studies and a narrative of psychosocial experiences and their impact upon caregiver well‐being was developed.

Results

Fifteen HNC papers which included exploration of the psychosocial experiences of oropharyngeal cancer caregivers following (chemo)radiotherapy were selected. Findings were synthesised to develop five themes: an emotional struggle, supporting nutrition, altered lifestyles, changes within relationships and support needs.

Conclusions

The completion of (chemo)radiotherapy signalled a transition for these caregivers as they undertook burdensome responsibilities. Experiences indicated that preparation for the role, assessment of needs, and targeted support is required. Additionally, caregivers' recognition by healthcare professionals as caring partners could help moderate this demanding experience.
Stochastic representation of spatial variability in thaw depth in permafrost boreal forests
Authors: Nakai Taro , Hiyama Tetsuya , Kotani Ayumi , Iijima Yoshihiro , Ohta Takeshi , Maximov Trofim C.
Published: August 2023

A simple stochastic representation of the spatial variability in thaw depth is proposed. Thaw depth distribution measured in the two larch‐type forests in eastern Siberia, Spasskaya Pad and Elgeeii, showed different spatial, seasonal, and interannual variability, respectively. Year‐to‐year variation in active‐layer thickness was minor in Spasskaya Pad compared to Elgeeii. A gamma distribution adequately represented both sites' thaw depth spatial variability as the cumulative probability. Thus, we developed a simple model using the gamma distribution that illustrates the spatial variability in thaw depth at any thawing stage as a function of a given mean thaw depth. A hierarchy of models was introduced that sequentially considered the constant state, linearity, and nonlinearity in the dependence of the rate parameter of the gamma distribution on the mean thaw depth. Although the requirements of the model levels differed between Spasskaya Pad and Elgeeii, the proposed model successfully represented the spatial variability in thaw depth at both sites during different thaw seasons.
Optimization of Activation Annealing Condition for Boron‐Implanted Diamond
Authors: Seki Yuhei , Kurashima Rintaro , Yoshihara Minami , Hoshino Yasushi
Published: August 2023

Impurity activation of dopants implanted in diamond is one of the crucial issues for device application of diamond. Boron impurity atoms are introduced in diamond, which expectedly act as acceptors, by ion implantation technique, and are investigated the optimum annealing time for the effective dopant activation. The impurity doping is performed by boron ion implantation at multiple incident energies to obtain a uniform dopant concentration from the surface to 350 nm depth followed by activation annealing at 1300 °C for 5–240 min. The electrical properties of specific resistance, carrier concentration, and conduction type are analyzed as a function of temperature from room temperature to 873 K. The estimated ionization energy is strongly dependent on the annealing time and asymptotically approaches to 0.3 eV, which is theoretically expected ionization energy of acceptor boron, with increasing annealing time. A shorter annealing time ( does not sufficiently recover radiation damages caused by ion implantation forming deep levels, which act as irregular conduction. It is consequently found that an optimum window of annealing time for effective dopant activation and suggested carrier transport mechanisms depending on the annealing time.
Cover Image
Authors: Wu Shun , Lu Dingchun , Gajendran Babu , Hu Qilan , Zhang Jian , Wang Shengquan , Han Minzhen , Xu Yini , Shen Xiangchun
Published: August 2023

The cover image is based on the Research Article Tanshinone IIA ameliorates experimental diabetic cardiomyopathy by inhibiting endoplasmic reticulum stress in cardiomyocytes via SIRT1 by Shun Wu et al., https://doi.org/10.1002/ptr.7831.

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Contrasting the evolution of radiation fog over a heterogeneous region in southwest France during the SOFOG3D campaign
Authors: Thornton J. , Price J. D. , Burnet F. , Lac C.
Published: August 2023

Observations made during the recent SOuth‐west FOGs 3D experiment (SOFOG3D) have been used to investigate the formation and evolution of radiation fog over heterogeneous forest plantations. The focus was on comparing measurements made at a relatively open site on arable land with those made in an approximately 700‐m diameter field surrounded by tree plantations, with both sites hosting an instrumented 50‐m mast. These data showed that at the more sheltered site radiation fog tended to form earlier than at the more open site. This coincided with more rapid decreases and lower minima in both near‐surface temperatures and vertical turbulence from the late afternoon. It is proposed here that the surrounding forest creates a sheltering effect, which can cause a reduction in vertical turbulence and therefore the mixing of cool near‐surface air with warmer air aloft. The near‐surface region is therefore able to cool rapidly, enabling fog to form more readily. Data from additional sites with varying surroundings supported the findings that the more sheltered sites tended to exhibit lower near‐surface nocturnal temperatures. However, the onset of fog formation observed at these additional sites suggested that there could be a limit to how sheltered a site may be before fog formation is inhibited rather than enabled by the surroundings.
Influencing factors associated with the second dominant pattern of the Indian summer monsoon
Authors: Yadav Ramesh Kumar
Published: August 2023

The interannual variation of the Indian summer monsoon (ISM) affects millions of people in India and the global weather and climate. The teleconnections that affect this variation are not stable. The recent four decades of the second dominant mode of ISM rainfall show a unique north–south tripole pattern, with above‐normal rainfall in the north and peninsular India sandwiching suppressed rainfall in central‐east India. The pattern relates to extending the Indo‐Pacific warm‐pool's warmer sea‐surface temperature (SST) towards the south of the equatorial eastern Indian Ocean. Most of the time, this warming and the extension of the warm‐pool's warmer SST are associated with La Niña events, which activate more in situ vigorous convection. The Rossby‐gyres generated west of the equatorial heating increase the tropospheric height over north India, shifting and strengthening the Tibetan High northwards, facilitating heavy rainfall in the north. Meanwhile, the more vigorous convection south of the equatorial eastern Indian Ocean produces compensatory subsidence over central‐east India, suppressing rainfall. The northern hemispheric Rossby‐gyres brings anomalous cyclonic circulation over peninsular India, producing excess rainfall. Also, the dipole pressure anomaly between the northwest Pacific and south tropical Indian Ocean generates anomalous lower‐level easterly winds over the Bay of Bengal. It supplies excess moisture to the north India convections. The co‐occurrence of the active Atlantic intertropical convergence zone supports this tripole rainfall pattern. This teleconnection could further be examined in climate models.
Spatially variable effects of streamflow on water temperature and thermal sensitivity within a salmon‐bearing watershed in interior British Columbia, Canada
Authors: Ulaski Marta E. , Warkentin Luke , Naman Sean M. , Moore Jonathan W.
Published: August 2023

Warming temperatures can have negative consequences for aquatic organisms, especially cold‐adapted fishes such as Pacific salmon. The magnitude of warming is related to the thermal sensitivity of streams in salmon‐bearing watersheds (i.e., change in stream temperature for every 1°C increase in air temperature), which can vary based on several factors including streamflow. Management actions to increase streamflow may therefore benefit salmon by decreasing thermal sensitivity. However, the effects of streamflow on thermal sensitivity are often complex, as the temperature of flow inputs can directly increase or decrease temperatures. This study aimed to disentangle the influence of streamflow on thermal sensitivity and stream temperature over 4 years in the Nicola River, a regulated semiarid watershed in south‐central British Columbia, Canada. A statistical modeling approach was used to estimate streamflow effects on stream temperatures and thermal sensitivity (i.e., relationship of regional air temperature to stream temperature) at 12 sites from 2018 to 2021. Streamflow had a variable influence on stream temperatures across the watershed via both direct effects and by modulating thermal sensitivity. At a given site, streamflow was generally negatively associated with summer daily mean stream temperature, but the magnitude of its influence varied among locations and years. The influence of streamflow on thermal sensitivity was also highly variable both spatially and temporally. The analysis suggests that there may be complex relationships between streamflow, stream temperature, and thermal sensitivity, which complicates the efficacy of flow as a lever to mitigate high temperatures in regulated systems.
Influence of manure and tillage on soil carbon and soil organic matter in silt loam soils of corn–soybean–forage systems
Authors: Bridges Kathleen M. , Das Srabani , Neikirk Heather , Lal Rattan
Published: August 2023

Introduction

An increasing number of farms in Northeast Ohio are being managed under reduced or conservation tillage practices, while those under conventional or intensive tillage are decreasing. Additionally, the use of on‐site farm manure among the growers is commonplace. Therefore, it is important to understand how the various management practices of these farms are impacting soil health, soil carbon stocks and crop yields.

Materials and Methods

This on‐farm study takes place in the temperate climate of the midwestern United States on a silt loam soil. It focuses on the impact of tillage (mouldboard plough [MP], vertical/chisel tillage [VT] and no‐tillage [NT]) and fertilizer (manure included or not) management practices on soil properties. Twelve agriculture fields and two woodland sites, for reference, on Canfield silt loam soils were selected for assessment in this project. Corn (Zea mays L.)–soybean (Glycine max L.) rotations and mixed forage Hayfields were the crops considered. Crop yields at each farm along with soil organic matter (SOM), total carbon (TC), total nitrogen (TN), bulk density, pH, soil test phosphorus (P), potassium (K) and sulphur (S) were assessed at two depths, 0–15 and 15–30 cm. Results of the first 2 years of the study (2020 and 2021) are presented here.

Results

At the surface soil depth (0–15 cm), TC content was not different among cultivated fields (36 Mg  ha−1), but was significantly less than Hayfields, which had the same amount of TC as the wood sites (58 Mg ha−1). There was no significant difference in soil test P, K or S due to tillage. Analysis of variance revealed no statistical difference due to fertilizer. At the soil surface depth, principal component analysis, supported by analysis of similarities (ANOSIM), determined that measurements of TC, TN and SOM distinguished a difference in Hayfields compared to cultivated fields (R‐statistic = 0.33; p = 0.001), but little difference when the 15–30 cm soil depth was considered (R‐statistic = 0.17; p = 0.001). ANOSIM also determined a slightly significant (R‐statistic = 0.065; p = 0.031) difference in fertilizer at the deeper soil depth. Correlation analysis revealed a strong positive relationship between SOM and corn grain yield (r = 0.59) and TN and corn grain yield (r = 0.39).

Conclusions

There was no significant loss of TC among increasing tillage intensities possibly due to the inclusion of manure fertilizer in tilled fields even though there were only slight statistical differences between fields that utilized manure and those that did not. The use of manure was not detrimental in terms of soil test P for most farms, but should be used judiciously. Inclusion of perennial crops such as hay in rotation with crop production can improve TC and TN content. Finally, increasing SOM could potentially increase corn grain yield, but no causal relationship has been determined yet.
Incorporating investigations of environmental racism into middle school science
Authors: Bradford Allison , Gerard Libby , Tate Erika , Li Rui , Linn Marcia C.
Published: August 2023

To promote a justice‐oriented approach to science education, we formed a research‐practice partnership between middle school science teachers, their students, curriculum designers, learning scientists, and experts in social justice to co‐design and test an environmental justice unit for middle school instruction. We examine teacher perspectives on the challenges and possibilities of integrating social justice into their standards‐aligned science teaching as they participate in co‐design and teach the unit. The unit supports students to investigate racially disparate rates of asthma in their community by examining pollution maps and historical redlining maps. We analyze interviews and co‐design artifacts from two teachers who participated in the co‐design and taught the unit in their classrooms. Our findings point to the benefits of a shared pedagogical framework and an initial unit featuring local historical content to structure co‐design. Findings also reveal that teachers can share similar goals for empowering students to use science knowledge for civic action while framing the local socio‐political factors contributing to the injustice differently, due in part to different institutional supports and constraints. Student interviews and a pre/postassessment illustrate how the unit facilitated students' progress in connecting socio‐political and science ideas to explain the impacts of particulate matter pollution and who is impacted most. Analyses illuminate how teachers' pedagogical choices may influence whether and how students discuss the impact of systemic racism in their explanations. The findings inform refinement of the unit and suggest supports needed for co‐design partnerships focused on integrating social justice and science.
Insights into Unconventional Intramolecular CH⋅⋅⋅CO Interaction in Os3(CO)9(μ‐H)2(μ3‐η1: η1: η2‐C16H8) Crystal: A QTAIM, NCI, and NBO Exploration
Authors: Cañavera‐Buelvas Farrah , Ospina‐Castro María , Cubillán Néstor
Published: August 2023

This work presents a study investigating the inter‐ and intra‐molecular interactions within the Os3(CO)9(μ‐H)2(μ3‐η1: η1: η2‐C16H8) crystal. The crystal‘s behavior is analyzed by comparing experimental distances, revealing intriguing interactions. In the isolated molecule, an unconventional pyrene‐C−H⋅⋅⋅CO interaction is observed, an electron transfer from σ(C−H) to π*(CO). Strikingly, the Quantum Theory of Atoms in Molecules identifies similarities to an intramolecular charge‐inverted hydrogen bond, despite its relatively low stability due to proximity to critical points. Energy surface scans demonstrate that the interaction arises from van der Waals strain induced by the crystal‘s packing structure. The proximity between carbonyl and pyrene facilitates electron transfer between σ(C−H) and π*(CO) at distances similar to the crystal structure. A significant correlation is established between total energy and the ratio (|V|/G) of potential energy density (V) to Lagrangian kinetic energy (G) at bond (BCP) and ring (RCP) critical points, underscoring the role of electron delocalization on the pseudo‐ring in determining the existence and characteristics of these interactions. In conclusion, this study provides valuable insights into molecular interactions within the Os3(CO)9(μ‐H)2(μ3‐η1: η1: η2‐C16H8) crystal, enriching our understanding of crystal interactions and offering perspectives for further exploration in this field.
Discovery of Natural Multitarget Xanthine Oxidase Inhibitors for Therapeutic Hyperuricemia Using Virtual Screening, Network Pharmacology and in vitro Experimental Verification
Authors: Cao Luxi , Ma Bei , Yi Bingxiang , Liu Yaru , Sun Jiaying
Published: August 2023

In this research, based on an important target xanthine dehydrogenase/oxidase (XDH/XO) of therapeutical hyperuricemia, natural multitarget XO inhibitors are discovered from Chinese herbal medicine. As a result, 31 natural active compounds are found using network pharmacology, molecular docking and dynamic simulation computational approaches. Further experimental verification shows that hesperetin, notopterol and cnidimol B are the promising lead compounds as multitarget XO inhibitors. Moreover, hesperetin, as an obvious competitive inhibitor, has the best bioactivities (IC50=13.63±0.12 μM). Additionally, inhibitory mechanism illustrates that these compounds treat hyperuricemia through targets HPRT1, NT5E, XDH, HSP90AA1, STAT3, ESRI, PPARG, MAPK1, MAPK3 SIRT1, mTOR and TLR4. Relevant signaling pathways involve in SCF‐Kit signaling pathway, interleukin signaling pathway, immune system, PDGFR signaling pathway in disease, and cellular response to heat stress. Therefore, the current research provides a new idea for discovery and development of novel XOIs, and has innovative significance for the expansion of related drug research.
Olive Leaves‐Derived Hierarchical Porous Carbon as Cathode Material for Anti‐Self‐Discharge Zinc‐Ion Hybrid Capacitor
Authors: Li Hongxia , Su Pengyuan , Liao Quanxing , Liu Yongdong , Li Yunfeng , Niu Xiaohui , Liu Xiaoyu , Wang Kunjie
Published: August 2023

As a promising low‐cost and high‐safety energy storage candidate, zinc‐ion hybrid capacitors (ZIHCs) have received extensive attention. For maximizing the advantages of ZIHC with high energy density and high power density, the structural engineering of the porous carbon materials is the crucial and effective strategy. Herein, an oxygen‐enriched hierarchical porous carbon has been fabricated from the pyrolysis of olive leaves combing the chemical activation. The abundant interfacial active sites and short ions/electrons transfer length endow the hierarchical porous carbon cathode with high ions adsorption capacity and fast kinetic behaviors. Meanwhile, the oxygen‐rich functional groups can provide extra pseudocapacitance and improve the wettability and conductivity of porous carbon. Benefiting from these advantages, an anti‐self‐discharge ZIHC device with a high energy‐power feature has been assembled. The electrochemical process is studied by ex situ X‐ray diffraction (XRD) and scanning electron microscope (SEM) methods. Finally, an excellent energy density of 136.3 W h kg−1, and high power output of 20 kW kg−1, as well as long cycle life with 91% capacity retention over 20 000 cycles at 10 A g−1 are realized by as‐assembled ZIHC.
Engineering Unsymmetrically Coordinated Fe Sites via Heteroatom Pairs Synergetic Contribution for Efficient Oxygen Reduction
Authors: An Qizheng , Zhang Xu , Yang Chenyu , Su Hui , Zhou Wanlin , Liu Meihuan , Zhang Xiuxiu , Sun Xuan , Bo Shuowen , Yu Feifan , Jiang Jingjing , Zheng Kun , Liu Qinghua
Published: August 2023

Single‐atom Fe catalysts are considered as the promising catalysts for oxygen reduction reaction (ORR). However, the high electronegativity of the symmetrical coordination N atoms around Fe site generally results in too strong adsorption of *OOH intermediates on the active site, severely limiting the catalytic performance. Herein, a “heteroatom pair synergetic modulation” strategy is proposed to tailor the coordination environment and spin state of Fe sites, enabling breaking the shackles of unsuitable adsorption of intermediate products on the active centers toward a more efficient ORR pathway. The unsymmetrically Co and B heteroatomic coordinated Fe single sites supported on an N‐doped carbon (Fe─B─Co/NC) catalyst perform excellent ORR activity with high half‐wave potential (E1/2) of 0.891 V and a large kinetic current density (Jk) of 60.6 mA cm−2, which is several times better than those of commercial Pt/C catalysts. By virtue of in situ electrochemical impedance and synchrotron infrared spectroscopy, it is observed that the optimized Fe sites can effectively accelerate the evolution of O2 into the *O intermediate, overcoming the sluggish O─O bond cleavage of the *OOH intermediate, which is responsible for fast four‐electron reaction kinetics.
Enhancing Adsorption Desulfurization Performance Using Enriched Cu(I) Sites over Microenvironment‐Modulated HKUST‐1
Authors: Lu Ping , Qi Zhaoyang , Chen Jie , Ye Changshen , Qiu Ting
Published: August 2023

High‐efficiency adsorption of aromatic sulfur‐containing compounds from liquid hydrocarbon fuels over metal‐organic frameworks (MOFs) is challenging because of inert metal sites. A new method, the Ce‐enhanced modulation of MOFs’ microenvironment, is proposed to modulate the –COO···Cu(II)– coordination microenvironment of Hong Kong University of Science and Technology (HKUST‐1) using Ce(III) as a molecular scalpel for fabricating abundant high‐efficiency Cu(I) and Cu‐coordination‐unsaturated sites and improving the pore structures around adsorptive sites. The optimal CH‐250 thus exhibits adsorptive capacities for 20.2, 28.0, and 58.3 mg S g–1 of thiophene, benzo‐thiophene, and dibenzothiophene, respectively, which are superior to most reported MOFs, zeolites, and nanoporous carbons. The constructed Cu(I) sites show stronger affinity for dibenzothiophene (−0.86 eV) than the initial Cu(II) (−0.74 eV) for out‐of‐plane adsorption. Further, they are far stronger in‐plane adsorption interactions in DBT/CH‐250 (−0.90 eV) than those in DBT/HKUST‐1 (−0.37 eV). Thus, molecular engineering for modulating the coordination microenvironment of MOFs shows great potential for adsorption desulfurization.
Unraveling the Origin of Donor‐Like Effect in Bismuth–Telluride‐Based Thermoelectric Materials
Authors: Liu Feng , Zhang Min , Nan Pengfei , Zheng Xin , Li Yuzheng , Wu Kang , Han Zhongkang , Ge Binghui , Zhao Xinbing , Fu Chenguang , Zhu Tiejun
Published: August 2023

The donor‐like effect, depicting the uncontrollable increase of electron density that can significantly alter the thermoelectric performance of both p‐type and n‐type polycrystalline Bi2Te3‐based materials, has long been an intriguing phenomenon, while its origin is still elusive. Herein, it is found that different from the common argument, the donor‐like effect in Bi2Te3‐based polycrystals is a result of the oxygen‐adsorption‐induced evolution of the point defects. The dominant point defect in stoichiometric zone‐melted Bi2Te3 ingot is the acceptor‐like . During the fabrication of high‐strength polycrystals, the exposure of the powders to the air leads to their absorption of oxygen and the formation of secondary phase Bi2TeO5 in the following sintering process. This brings about a change of local chemical equilibrium and promotes the evolution of the intrinsic point defect from acceptor‐like to donor‐like . Notably, if the fabrication process is strictly controlled to minimize oxygen adsorption, the evolution of the point defects will be avoided, whereby the donor‐like effect disappears. Consequently, a reproducible high zT value of 1.0 at 325 K can be achieved in Bi2Te2.7Se0.3‐based polycrystals. These results highlight the importance of understanding the evolution of point defects, which is crucial for developing high‐performance Bi2Te3‐based polycrystals and corresponding fabrication processes.
Assessing the Feasibility of Cold Forming of Automotive Parts from Quenched and Partitioned Martensitic Stainless Steels
Authors: de Pablos Juan Luis , Sierra-Soraluce Andres , Sabirov Ilchat , Muratori Marta , Smith Ali
Published: August 2023

Sheet metal forming is among the most widely employed processes in manufacturing. Its economic feasibility relies on many factors, including the mechanical properties of the processed materials, energy efficiency of the metal‐forming processes, and quality of the manufactured parts. This work focuses on developing a computational approach to assess the mechanical behavior of quenched and partitioned (QP) martensitic stainless steels (MSSs) undergoing cold forming, aiming at the serial production of automotive parts. The Johnson–Cook (J–C) constitutive model and forming limit diagram (FLD) are derived and validated for each alloy using the experimental data from tensile and Nakajima tests. From the simulated FLD, a theoretical forming limit stress diagram (FLSD) is calculated. The latter is used as a fracture criterion for the cold‐forming process. Cold stamping of two automotive parts, B‐pillar and tunnel, is modeled using the J–C constitutive model and the FLSD. It is demonstrated that the tunnel can be successfully cold‐formed from all three studied steels. In contrast, extensive cracking is expected during the cold forming of the B‐pillar from all materials. It is envisaged that these computational models can be employed for the assessment of any comparable part manufacturing procedure from the QP MSSs.
A comprehensive survey of personal knowledge graphs
Authors: Chakraborty Prantika , Sanyal Debarshi Kumar
Published: August 2023

Information that can encapsulate a person's daily life and its different aspects provides insightful knowledge. This knowledge can prove to be more useful than general knowledge for improving personalized tasks. When it comes to storing such knowledge, personal knowledge graphs (PKGs) come in as handy saviors. PKGs are knowledge graphs which store details that are pertinent to a user but not, in general, useful to the rest of humanity. Conversational agents can access these PKGs to answer queries related to the user's day‐to‐day life, whereas recommender systems can harness the knowledge stored in PKGs to make personalized suggestions. Despite the immense applicability of PKGs, there has not been significant research in this area. We present an extensive review of PKGs. We categorize them according to the domains in which they are most relevant; in particular, we highlight the use of PKGs in medicine, finance, and education and research. We also categorize the different ways of constructing a PKG based on the source of data required for such constructions. Furthermore, we discuss the limitations of PKGs and suggest directions for future work.

This article is categorized under:

Fundamental Concepts of Data and Knowledge > Human Centricity and User Interaction

Fundamental Concepts of Data and Knowledge > Knowledge Representation

Technologies > Artificial Intelligence
Towards an Effective Artificial Intelligence Systems for Condition Monitoring of Off-Shore Wind Turbines: The Application of Sensor Fusion
Authors: Al-Habaibeh Amin , Shakmak Bubaker , Boateng Ampea , Lee Hyunjoo
Published: August 2023

In the face of increasing energy demand and the upsurge in the recent energy prices post Covid-19 pandemic, scientists and technologists around the world are working to develop more efficient renewable energy alternatives. Among such technologies, wind turbines play an important role as a very mature clean energy technology. But minimising maintenance costs and downtime is critical for off-shore wind turbines; and researchers around the world are trying to develop comprehensive online and real time monitoring systems to monitor the health of wind turbines to advance condition-based maintenance (CBM) strategies in order to reduce cost and enhance availability. There is a need to use sensor fusion since a single type of sensor is not expected to capture the needed information regarding the health of the wind turbine due to the complexity of the operational conditions such as wind speed, wind direction, power output, environmental temperatures; in addition to many other factors. Industrial case study will be presented in this paper to explore the sensor fusion option and discus how to select the most suitable sensors to detect a specific fault, or group of faults, among hundreds of sensors. This is considered a critical step for the development of an artificial intelligence CBM system. The paper presents the use of the ASPS approach (Automated Sensor and Signal Processing Selection). The results show that the suggested methodology could easily identify the sensors and signal processing methods that are sensitive to fault conditions for future diagnostics and prognostics.
CFD Based Aerodynamics Conjugate Heat Transfer and Airgap Fluid Flow Thermal Analysis to a Wheel Hub Motor for Electric Scooters
Authors: Divakaran A. M. , Abo-Serie E. , Gkanas E. I. , Jewkes J. , Shepherd S.
Published: August 2023

The geometry of commercially available wheel hub motors inherently restricts packaging space and may prevent the introduction of more sophisticated, efficient, and expensive cooling systems. Due to the limited available space in the wheels, commercial hub motors often rely on aerodynamic passive cooling. The small air-gap (0.5–1 mm) between the coils and the magnets results in heat transfer to the magnets and consequently increases their temperature. As a result, the perfeormance of the permanent magnets (PMs) will be limited and also will heavily affect their lifetime; thus, advanced cooling strategies must be introduced. In the current study, a three-dimensional (3D) thermal model was developed for a commercially available 500 W scooter hub motor under a constant heat load of 180 W using Computational Fluid Dynamics (CFD) (= 64%).The spatial distribution of the temperature for the motor parts are evaluated considering both the internal and external fluid flow dynamics. Further, analysis of airflow in the the gap is performed and the results from the CFD is compared with the published correlations. The flow in such small motor was found to be laminar with Taylor number below 40. Results also showed that enhancement of the cooling is necessary to avoid damage of the winding vernish and to reduce the magnets temperature particularly when the motor works at high torque with low efficiency.
Introduction
Authors: Hu Hong-Song
Published: August 2023

This chapter gives a brief introduction to sliding base (SB) structures. The basic idea of SB structures is interpreted, and experimental studies on the properties of potential materials for using in the sliding interfaces and analytical studies on the responses of SB structures under harmonic and earthquake ground motions are reviewed.
Response Histories of Sliding Base Structures Under Earthquake Excitation
Authors: Hu Hong-Song
Published: August 2023

In this chapter, the equations of motion for multistory sliding base (SB) structures under three-component excitations are established, and numerical methods for computing the response histories of SB structures are also developed. Typical response histories of SB structure under earthquake excitation are presented, aiming to provide the readers an overview of how a SB structure response when subjected to earthquake excitation. This chapter lays a foundation for the following chapters, which focus on specific aspects of SB structures, respectively.
Equivalent Lateral Forces for Design of Multistory Sliding Base Structures
Authors: Hu Hong-Song
Published: August 2023

In Chap. 4, the peak superstructure responses of single-story sliding base (SB) structures subjected to three-component earthquake excitation were studied, and simplified equations for estimating the peak superstructure responses were also developed. For multistory SB structures, these equations may still be used to determine the total earthquake force acting on the superstructure; however, they are not sufficient to determine the earthquake forces acting on each story of a multistory structure. For this reason, this chapter focuses on the development of equivalent lateral forces for the design of multistory SB structures.
Boson star normal modes
Authors: Chan James Hung-Hsu , Sibiryakov Sergey , Xue Wei
Published: August 2023

Abstract

Boson stars are gravitationally bound objects that arise in ultralight dark matter models and form in the centers of galactic halos or axion miniclusters. We systematically study the excitations of a boson star, taking into account the mixing between positive and negative frequencies introduced by gravity. We show that the spectrum contains zero-energy modes in the monopole and dipole sectors resulting from spontaneous symmetry breaking by the boson star background. We analyze the general properties of the eigenmodes and derive their orthogonality and completeness conditions which have non-standard form due to the positive-negative frequency mixing. The eigenvalue problem is solved numerically for the first few energy levels in different multipole sectors and the results are compared to the solutions of the Schrödinger equation in fixed boson star gravitational potential. The two solutions differ significantly for the lowest modes, but get close for higher levels. We further confirm the normal mode spectrum in 3D wave simulations where we inject perturbations with different multipoles. As an application of the normal mode solutions, we compute the matrix element entering the evaporation rate of a boson star immersed in a hot axion gas. The computation combines the use of exact wavefunctions for the low-lying bound states and of the Schrödinger approximation for the high-energy excitations.
A connection between regular black holes and horizonless ultracompact stars
Authors: Carballo-Rubio Raúl , Di Filippo Francesco , Liberati Stefano , Visser Matt
Published: August 2023

Abstract

We illustrate that regular black holes and horizonless stars, typically considered as quite distinct families of black hole mimickers, are intimately intertwined. We show that any spherically symmetric regular black hole can be continuously deformed into a horizonless star under the mild conditions of non-negativity of gravitational energy (Misner-Sharp quasi-local mass), and an assumed linear relation between the latter and the Arnowitt-Deser-Misner (ADM) mass. We illustrate this general result by considering the family of geometries proposed by Hayward as the description of regular black holes, and we also describe the properties of the corresponding horizonless stars. The form of the associated effective stress-energy tensor shows that these horizonless stars can be identified as anisotropic gravastars with a soft surface and inner/outer light rings. We also construct dynamical geometries that could describe the evolution of regular black holes towards horizonless stars, and show that it is plausible that the effective stress-energy tensor in the first stages of evolution is generated by semiclassical effects, in agreement with independent works analyzing semiclassical backreaction.
Boundary confining dualities and Askey-Wilson type q-beta integrals
Authors: Okazaki Tadashi , Smith Douglas J.
Published: August 2023

Abstract

We propose confining dualities of $$ \mathcal{N} $$
N
= (0, 2) half-BPS boundary conditions in 3d $$ \mathcal{N} $$
N
= 2 supersymmetric SU(N), USp(2n) and SO(N) gauge theories. Some of these dualities have the novel feature that one (anti)fundamental chiral has Dirichlet boundary condition while the rest have Neumann boundary conditions. While some of the dualities can be extended to 3d bulk dualities, others should be understood intrinsically as 2d dualities as they seem to hold only at the boundary. The gauge theory Neumann half-indices are well-defined even for theories which contain monopole operators with non-positive scaling dimensions and they are given by Askey-Wilson type q-beta integrals. As a consequence of the confining dualities, new conjectural identities of such integrals are found.
Almost multiplicative maps with respect to almost associative operations on Banach algebras
Authors: Kochanek Tomasz
Published: August 2023

We prove an Ulam type stability result for a non-associative version of the multiplicativity equation, that is, $$T(xy)=\Psi (T(x),T(y))$$

T
(
x
y
)
=
Ψ
(
T
(
x
)
,
T
(
y
)
)

, where T is a unital bounded operator acting from an amenable Banach algebra to a dual Banach algebra.
MST1 mediates doxorubicin-induced cardiomyopathy by SIRT3 downregulation
Authors: Schirone Leonardo , Vecchio Daniele , Valenti Valentina , Forte Maurizio , Relucenti Michela , Angelini Annalisa , Zaglia Tania , Schiavon Sonia , D’Ambrosio Luca , Sarto Gianmarco , Stanzione Rosita , Mangione Elisa , Miglietta Selenia , Di Bona Anna , Fedrigo Marny , Ghigo Alessandra , Versaci Francesco , Petrozza Vincenzo , Marchitti Simona , Rubattu Speranza , Volpe Massimo , Sadoshima Junichi , Frati Luigi , Frati Giacomo , Sciarretta Sebastiano
Published: August 2023

Heart failure is a major side effect of doxorubicin (DOX) treatment in patients with cancer. However, the mechanisms underlying the development of DOX-induced heart failure need to be addressed. This study aims to test whether the serine/threonine kinase MST1, a major Hippo pathway component, contributes to the development of DOX-induced myocardial injury. C57BL/6J WT mice and mice with cardiomyocyte-specific dominant-negative MST1 (kinase-dead) overexpression received three weekly injections of DOX, reaching a final cumulative dose of 18 mg/kg. Echocardiographic, histological and biochemical analyses were performed six weeks after the first DOX administration. The effects of MST1 inhibition on DOX-induced cardiomyocyte injury were also tested in vitro. MST1 signaling was significantly activated in cardiomyocytes in response to DOX treatment in vitro and in vivo. Wild-type (WT) mice treated with DOX developed cardiac dysfunction and mitochondrial abnormalities. However, these detrimental effects were abolished in mice with cardiomyocyte-specific overexpression of dominant-negative MST1 (DN-MST1) or treated with XMU-MP-1, a specific MST1 inhibitor, indicating that MST1 inhibition attenuates DOX-induced cardiac dysfunction. DOX treatment led to a significant downregulation of cardiac levels of SIRT3, a deacetylase involved in mitochondrial protection, in WT mice, which was rescued by MST1 inhibition. Pharmacological inhibition of SIRT3 blunted the protective effects of MST1 inhibition, indicating that SIRT3 downregulation mediates the cytotoxic effects of MST1 activation in response to DOX treatment. Finally, we found a significant upregulation of MST1 and downregulation of SIRT3 levels in human myocardial tissue of cancer patients treated with DOX. In summary, MST1 contributes to DOX-induced cardiomyopathy through SIRT3 downregulation.
A Friedlander-Suslin Theorem over a Noetherian Base Ring
Authors: van der Kallen Wilberd
Published: August 2023

Let k be a noetherian commutative ring and let G be a finite flat group scheme over k. Let G act rationally on a finitely generated commutative k-algebra A. We show that the cohomology algebra $$H^*(G,A)$$

H
∗

(
G
,
A
)

is a finitely generated k-algebra. This unifies some earlier results: If G is a constant group scheme, then it is a theorem of Evens (Trans. Amer. Math. Soc. 101, 224–239, 1961, Theorem 8.1), and if k is a field of finite characteristic, then it is a theorem of Friedlander and Suslin (Invent. Math. 127, 209–270, 1997). If k is a field of characteristic zero, then there is no higher cohomology, so then it is a theorem of invariant theory.