bluuebunny/crossref_metadata_2025 huggingface dataset:
HS‐IDEOR—A tool for conceptual modeling and designing of hardware architectures focused on object recognition
Authors: Guzmán‐Ramírez Enrique , García Iván , Arroyo‐Fernández Ignacio , Santos‐Villalobos Alberto
Published: April 2022

Considering the increasing demand for object recognition systems, it is crucial that modern engineering courses include tools and methods to ensure that students acquire the theoretical and practical skills necessary to become specialists in designing such systems. This paper introduces a hardware‐software integrated development environment to support and accelerate the teaching/learning process of conceptual modeling and hardware architectures design focused on object recognition. In addition, our proposal facilitates the implementation of modular and hybrid object recognition schemes, offering great flexibility in the study of such systems. An empirical evaluation was conducted with 30 fourth‐year undergraduate students who designed and implemented an object recognition system in the Computer Vision course of the Bachelor's Degree in Computer Science and Engineering at the Universidad Tecnológica de la Mixteca, Mexico. The results achieved from designing, modeling, and implementing a hardware architecture of the convolution process applied to edge detection in an image provided evidence that this approach empowered students with a more dynamic learning process.
Insights into Fe Species Structure‐Performance Relationship for Direct Methane Conversion toward Oxygenates over Fe‐MOR Catalysts
Authors: Fang Zhihao , Huang Mengyuan , Liu Bing , Chen Jie , Jiang Feng , Xu Yuebing , Liu Xiaohao
Published: April 2022

Direct oxidation of methane to value‐added products under mild conditions remains a grand challenge due to the problem of selective CH4 activation. Here we report a Fe‐MOR‐F catalyst prepared via freeze‐drying method, indicating excellent catalytic performance for the direct partial oxidation of methane using H2O2 under mild conditions. Various characterizations including XRD, NH3‐TPD, H2‐TPR, UV‐Vis, XPS, and EPR studies revealed that Fe‐MOR‐F catalyst possesses more highly dispersed monomeric and dimeric iron species, which is strongly correlated to its high catalytic activity for direct methane oxidation. The DFT calculations indicate the highly dispersed monomeric and dimeric iron species can effectively homogenize H2O2 into active hydroxyl groups, while iron clusters can decompose H2O2 into inactive O2. The EPR experiments show more ⋅OH was generated on Fe‐MOR‐F catalyst, which is in line with DFT calculation results. These structural characteristics endow Fe‐MOR‐F catalyst with superior catalytic performance for direct methane oxidation in terms of oxygenates yield (9.8 mol kgcat−1 h−1) and selectivity (91.8 %) at 80 °C. This work not only highlights the excellent catalytic performance of methane activation on the highly dispersed monomeric and dimeric iron species, but also promotes the potential application by freeze‐drying method for the preparation of the highly dispersed active species.
Promoted MoxCy‐based Catalysts for the CO2 Oxidative Dehydrogenation of Ethane
Authors: Marquart Wijnand , Raseale Shaine , Claeys Michael , Fischer Nico
Published: April 2022

The CO2 oxidative dehydrogenation reaction has the potential to play a role in the advancement of CO2‐utilizing catalytic reactions, co‐activating CO2 and short‐chained alkanes. Transition metal carbides are promising catalysts for this reaction, in particular MoxCy, however catalytic stability is a major challenge. In this study, the addition of a promoter (Fe, K, Ni or Pt) has shown to significantly influence the crystal structure of the carbide system as well as the acid‐base characteristics. K promotion decreased the number of acid sites, limiting ethane activation and the removal of the oxygen surface species formed in CO2 activation. The catalysts deactivate due to oxidation to MoOx. Fe decreased the initial activity, but it increased the stability of the oxygen surface species, which enhanced the stability of the catalyst and ethylene selectivity to outperform the unpromoted sample. Oxidation of the carbide and carbon deposition during the reaction could not be prevented. Ni promotion increases the number of basic sites, enhancing the CO2 activation, shown by the highest activity obtained during the reverse water‐gas‐shift experiments. At higher CO2 content in the feed the dry‐reforming reaction becomes the dominant reaction pathway. Pt suppressed the dry‐reforming reaction, but instead increased the direct dehydrogenation activity, accompanied by a high degree of carbon deposition. No oxidation to MoOx was observed at a stoichiometric CO2 to C2H6 feed ratio.
Statistical Analysis of the Measurement Noise in Dynamic Impedance Spectra
Authors: Chukwu Richard , Mugisa John , Brogioli Doriano , Mantia Fabio La
Published: April 2022

Different strategies can be used to acquire dynamic impedance spectra during a cyclic voltammetry experiment. The spectra are then analyzed by fitting them with a model using a weighted non‐linear least‐squares minimization algorithm. The choice of the weighting factors is not trivial and influences the value of the extracted parameters. At variance with the classic electrochemical impedance spectroscopy, dynamic impedance measurements are performed under non‐stationary conditions, making them typically more prone to errors arising from the voltage and current analog‐to‐digital conversion. Under the assumption that the noise in the voltage and current signals have a constant variance along the measurement and that it is uncorrelated between distinct samples, we calculate an expression for the expected variance of the error of the resulting immittances, which considers the specific procedure used to extract the spectra under the time‐varying nature of the measurements. The calculated variance of the error is then used as a rigorous way to evaluate the weighting factors of the least‐squares minimization, assuming that the fitted model is ideally exact and that there are no systematic errors. By exploring two classical electrochemical systems and fitting the measured spectra with a transfer function measurement model, namely with the Padé approximants, we show that the variance evaluated with our method captures the frequency dependence of the resulting residuals and can be used for reliably performing the complex non‐linear least‐squares fitting procedure.
Structure and Electrochemical Properties of LaMn1‐XNixO3
Authors: Li Jiayun , Luo Wangting , Wang Xiaoqian , Yu Chao , Zhang YuJie , Meng FanBin
Published: April 2022

LaMn1‐xNixO3nanoparticles were synthesized through hydrothermal synthesis and calcinations. The structural and electrochemical properties were studied to evaluate the effect of Ni doping on the materials as supercapacitor electrodes. The LaMn0.5Ni0.5O3sample presented a capacitance of 183 F ⋅ g−1(current density of 1 A ⋅ g−1) and a capacity retention of 83.5 % after 2000 charge‐discharge cycles. Theoretical calculations were performed to provide more insight into the electrochemical performance.
Advances in Z‐scheme semiconductor photocatalysts for the photoelectrochemical applications: A review
Authors: Li Jiaxin , Yuan Hao , Zhang Wenjie , Jin Bingjun , Feng Qi , Huang Jan , Jiao Zhengbo
Published: April 2022

With continuous consumption of nonrenewable energy, solar energy has been predicted to play an essential role in meeting the energy demands and mitigating environmental issues in the future. Despite being green, clean and pollution‐free energy, solar energy cannot be adopted directly as it cannot provide sufficiently high energy density to work in the absence of machinery. Thus, it is necessary to develop an effective strategy to convert and store solar energy into chemical energy to achieve social sustainable development using solar energy as the main power source. Photocatalysis, in which semiconductor photocatalysts play a key role, is one of the most promising candidates for realising the effective utilisation of sunlight in a green, low‐cost and environmentally friendly method. The photocatalytic efficiency of photocatalysts is considerably influenced by their compositions. Among the various heterostructures, Z‐scheme heterojunction is one of the most interesting architecture due to its outstanding performance and excellent artificial imitation of photosynthesis. Z‐scheme photocatalysts have attracted considerable attention in the past few decades. Herein, we review contemporary Z‐scheme systems, with a particular focus on mechanistic breakthroughs, and highlight current state‐of‐the‐art systems. Z‐type photocatalysts are classified as traditional, all‐solid‐state, direct Z‐schemes and S‐scheme photocatalysts. The morphology, characterisation and working mechanism of each type of Z‐scheme are discussed in detail. Furthermore, the applications of Z‐scheme in photoelectrochemical water splitting, nitrogen fixation, pollutant degradation and carbon dioxide reduction are illustrated. Finally, we outline the main challenges and potential advances in Z‐scheme architectures, as well as their future development directions.
Highly stretchable, durable, and breathable thermoelectric fabrics for human body energy harvesting and sensing
Authors: He Xinyang , Shi Jia , Hao Yunna , He Mantang , Cai Jiaxin , Qin Xiaohong , Wang Liming , Yu Jianyong
Published: April 2022

Stretchable thermoelectrics have recently attracted widespread attention in the field of self‐powered wearable electronics due to their unique capability of harvesting body heat. However, it remains challenging to develop thermoelectric materials with excellent stretchability, durable thermoelectric properties, wearable comfort, and multifunctional sensing properties simultaneously. Herein, an advanced preparation strategy combining electrospinning and spraying technology is proposed to prepare carbon nanotube (CNT)/polyvinyl pyrrolidone (PVP)/polyurethane (PU) composite thermoelectric fabrics that have high air permeability and stretchability (~250%) close to those of pure PU nanofiber fabrics. Furthermore, PVP can not only improve the dispersion of CNTs but also act as interfacial binders between the CNT and the elastic PU skeleton. Consequently, both the electrical conductivity and the Seebeck coefficient remain unchanged even after bending 1000 times. In addition, self‐powered sensors for the mutual conversion of finger temperature and language and detection of the movement of joints to optimize an athlete's movement state were successfully fabricated. This study paves the way for stretchable thermoelectric fabrics with fascinating applications in smart wearable fields such as power generation, health monitoring, and human–computer interaction.
The association between systemic inflammatory response index and in‐hospital mortality in patients with infective endocarditis
Authors: Cai Zhenzhen , Qiao Tengfei , Chen Ying , Xie Mengxiao , Zhou Jun
Published: April 2022

Background

Infective endocarditis (IE) has a significant mortality, and early identification of high‐risk patients and prediction of poor outcomes is of great significance. In recent years, increasing research has revealed the predictors associated with infective endocarditis prognosis. Systemic inflammatory response index (SIRI) is an important new indicator of inflammation. So far, there have been no reports on the relationship between SIRI and the prognosis of IE patients.

Hypothesis

The purpose of this study was to explore the value of SIRI in predicting in‐hospital death for patients with infective endocarditis (IE), so as to provide reference for improving the prognosis of patients with IE.

Method

A retrospective analysis was performed on the clinical data of patients with IE admitted to the First Affiliated Hospital of Nanjing Medical University from January 2017 to December 2019. SIRI was calculated according to the blood routine results of patients at admission; receiver operating characteristic curve was employed to determined the optimal cutoff value of SIRI. Patients were divided into groups (low SIRI group and high SIRI group; nonsurvivor group and survivor group) according to the levels of SIRI or their prognosis, and the general clinical features of the two groups were compared. Univariate and multivariate logistic regression analysis were performed to analyze the independent prognostic factors of in‐hospital death in IE patients.

Results

A total of 147 IE patients meeting the diagnostic criteria were included, including 102 males (69.4%) and 45 females (30.6%). There was statistically significant difference in SIRI level between nonsurvivor group and survivor group (p < .05). After adjusting for the related factors, the risk of in‐hospital death in the high SIRI was still a risk of in‐hospital death with statistical significance (hazard ratio = 5.053, 95% confidence interval: 1.426‒17.905, p = .012).

Conclusions

Higher SIRI level is independently associated with the risk of in‐hospital death in IE patients, and can be an independent predictor of poor outcome in IE patients.
On the performance of link functions in the beta ridge regression model: Simulation and application
Authors: Mustafa Sidra , Amin Muhammad , Akram Muhammad Nauman , Afzal Nimra
Published: April 2022

The beta regression model (BRM) is appropriate when the response variable is continuous and is in the form of ratios and proportions. For the estimation of the BRM, the maximum likelihood estimation (MLE) method is used with a specific link function. However, the MLE provides unstable results when the explanatory variables are correlated. In this study, we consider some ridge parameters for the beta ridge regression estimator (BRRE) under different link functions. However, mostly the researchers do not pay much attention to the suitable link function. So, we consider five link functions to see the performance of ridge parameters in the BRRE. For the performance assessment of ridge parameters and different link functions, a Monte Carlo simulation and a real application are considered, where mean squared error is used as the evaluation criterion. Both the simulation and example findings demonstrate that the BRRE with the log–log link function provides efficient results.
A Wrapper based feature extraction framework based on AlexNet deep convolutional neural network parameters optimized using gradient‐based optimizer for mammogram images
Authors: Sakthivel N. K. , Subasree S. , Malik Shaveta , Tyagi Amit Kumar
Published: April 2022

In this manuscript, a Wrapper based feature extraction framework based on AlexNet deep convolutional neural network (ADCNN) with gradient‐based optimizer (GBO) is proposed for early detection of breast cancer. In this input images are occupied as mini‐mammography image analysis society (MIAS) database. Then the images are pre‐processed to eliminate that noises using Markov random field (MRF) method. Image features are extracted by the process of Wrapper based feature extraction framework with ADCNN. Then, the weight parameters of ADCNN are optimizing through the aid of GBO. Then the mammogram images are characterized as normal or abnormal (malignant and benign) with SVM classifier. The simulation process is implemented on MATLAB platform. The proposed ADCNN‐SVM‐GBO attains higher accuracy 34.64%, 28.86%, 19.86%, 24.64%, 32.86%, higher Precision 28.07%, 18.96%, 16.86%, 25.86%, 26.86%, higher recall 27.86%, 32.54%, 27.86%, 23.95%, 19.97%, and the efficiency of the proposed method FE‐ADCNN‐GBO‐SVM is likened with the existing processes. Classification of mammograms depends features removal processes with support vector machine (FE‐LBP‐GLCM‐SVM), breast cancer classification with global discriminate features on mammographic images (FE‐GLCM‐ANN), enhancing breast cancer classification with (SMOTE) technique and pectoral muscle removal on mammographic images (FE‐SMOTE‐RF), application of artificial intelligence depends deep learning on breast cancer screening and imaging diagnosis (FE‐CNN‐CDCNN) respectively.
Tuning the Structure and Properties of N‐doped Positively Charged Polycyclic Aromatic Hydrocarbons
Authors: Radenković Slavko , Tomović Željko
Published: April 2022

A detailed study of the geometry, aromatic character, electronic and magnetic properties for a series of positively charged N‐doped polycyclic aromatic hydrocarbons (PAHs) was performed. Magnetic properties of the examined molecules were analyzed by means of the magnetically induced current density calculated using the diamagnetic‐zero version of the continuous transformation of origin of current density (CTOCD‐DZ) method. The comparative study of the local aromaticity of the studied molecules was performed using several different indices: energy effect (ef), harmonic oscillator model of aromaticity (HOMA) index, six centre delocalization index (SCI) and nucleus independent chemical shifts (NICS). The presence of N‐atoms in the inner rings was found to cause a planarity distortion in the studied N‐doped systems. The geometric changes and charged nature of the studied N‐doped systems do not significantly influence the current density and the local aromaticity distribution in comparison with the corresponding parent benzenoid hydrocarbons. The present study demonstrates how quantum chemical calculations can be used for rational design of novel PAHs and for fine tuning of their properties.
Stakeholder management, CSR commitment, corporate social performance: The moderating role of uncertainty in CSR regulation
Authors: Adomako Samuel , Tran Mai Dong
Published: April 2022

In spite of the burgeoning literature on corporate social responsibility (CSR), little is known about the mechanism through which stakeholder integration affects corporate social performance (CSP). Our study fills this gap in the CSR literature by testing a model that explains this mechanism. Using data from 228 firms, we found that stakeholder integration positively influences a firm's CSR commitment and this linkage is attenuated when uncertainty in CSR regulation is greater. In addition, the results revealed that a firm's CSR commitment mediates the relationship between stakeholder integration and CSP. Theoretical and practical contributions are discussed.
Amphiphilic Indoles as Efficient Phase‐Transfer Catalysts for Bromination in Water
Authors: Zhang Qingyu , Xu Yongyuan , Liang Xiaochen , Ke Zhihai
Published: April 2022

Brominated compounds are important, but they are usually prepared in organic solvents. Here, efficient amphiphilic indole‐based phase‐transfer organocatalysts were developed for environmentally benign bromination reactions in water. As test reactions, hydroxybromination of olefins and aromatic bromination could be conducted in a greener and more sustainable manner compared with methods using organic solvents, producing the corresponding bromides in good yields. Some pure products could be obtained without column chromatography.
Refinement of axonal conduction and myelination in the mouse optic nerve indicate an extended period of postnatal developmental plasticity
Authors: Balraj Annika , Clarkson‐Paredes Cheryl , Pajoohesh‐Ganji Ahdeah , Kay Matthew W. , Mendelowitz David , Miller Robert H.
Published: April 2022

Retinal ganglion cells generate a pattern of action potentials to communicate visual information from the retina to cortical areas. Myelin, an insulating sheath, wraps axonal segments to facilitate signal propagation and when deficient, can impair visual function. Optic nerve development and initial myelination has largely been considered completed by the fifth postnatal week. However, the relationship between the extent of myelination and axonal signaling in the maturing optic nerve is not well characterized. Here, we examine the relationship between axon conduction and elements of myelination using extracellular nerve recordings, immunohistochemistry, western blot analysis, scanning electron microscopy, and simulations of nerve responses. Comparing compound action potentials from mice aged 4–12 weeks revealed five functional distinct axonal populations, an increase in the number of functional axons, and shifts toward fast‐conducting axon populations at 5 and 8 weeks postnatal. At these ages, our analysis revealed increased myelin thickness, lower g‐ratios and changes in the 14 kDa MBP isoform, while the density of axons and nodes of Ranvier remained constant. At 5 postnatal weeks, axon diameter increased, while at 8 weeks, increased expression of a mature sodium ion channel subtype, Nav 1.6, was observed at nodes of Ranvier. A simulation model of nerve conduction suggests that ion channel subtype, axon diameter, and myelin thickness are more likely to be key regulators of nerve function than g‐ratio. Such refinement of axonal function and myelin rearrangement identified an extended period of maturation in the normal optic nerve that may facilitate the development of visual signaling patterns.
Lmx1b activation in axolotl limb regeneration
Authors: Yamamoto Sakiya , Kashimoto Rena , Furukawa Saya , Ohashi Ayaka , Satoh Akira
Published: April 2022

Background

Axolotls can regenerate their limbs. In their limb regeneration process, developmental genes are re‐expressed and reorganize the developmental axes, in which the position‐specific genes are properly re‐expressed. However, how such position specificity is reorganized in the regeneration processes has not been clarified. To address this issue, we focused on the reactivation process of Lmx1b, which determines the limb dorsal identity in many animals.

Results

Here, we show that Lmx1b expression is maintained in the dorsal skin before amputation and is activated after amputation. Furthermore, we demonstrate that only cells located in the dorsal side prior to limb amputation could reactivate Lmx1b after limb amputation. We also found that Lmx1b activation was achieved by nerve presence. The nerve factors, BMP2+FGF2+FGF8 (B2FF), consistently reactivate Lmx1b when applied to the dorsal skin.

Conclusions

These results imply that the retained Lmx1b expression in the intact skin plays a role in positional memory, which instruct cells about the spatial positioning before amputation. This memory is reactivated by nerves or nerve factors that can trigger the entire limb regeneration process. Our findings highlight the role of nerves in amphibian limb regeneration, including both the initiation of limb regeneration and the reactivation of position‐specific gene expression.
Harvest and density‐dependent predation drive long‐term population decline in a northern ungulate
Authors: Marrotte Robby R. , Patterson Brent R. , Northrup Joseph M.
Published: April 2022

The relative effect of top‐down versus bottom‐up forces in regulating and limiting wildlife populations is an important theme in ecology. Untangling these effects is critical for a basic understanding of trophic dynamics and effective management. We examined the drivers of moose (Alces alces) population growth by integrating two independent sources of observations within a hierarchical Bayesian population model. We used one of the largest existing spatiotemporal data sets on ungulate population dynamics globally. We documented a 20% population decline over the period examined. There was negative density‐dependent population growth of moose. Although we could not determine the mechanisms producing density‐dependent suppression of population growth, the relatively low densities at which we documented moose populations suggested it could be due to density‐dependent predation. Predation primarily limited population growth, except at low density, where it was regulating. After we simulated several harvest scenarios, it appeared that harvest was largely additive and likely contributed to population declines. Our results highlight how population dynamics are context dependent and vary strongly across gradients in climate, forest type, and predator abundance. These results help clarify long‐standing questions in population ecology and highlight the complex relationships between natural and human‐caused mortality in driving ungulate population dynamics.
Host in reserve: The role of common shrews (Sorex araneus) as a supplementary source of tick hosts in small mammal communities influenced by rodent population cycles
Authors: De Pelsmaeker Nicolas , Korslund Lars , Steifetten Øyvind
Published: April 2022

Rodents often act as important hosts for ticks and as pathogen reservoirs. At northern latitudes, rodents often undergo multi‐annual population cycles, and the periodic absence of certain hosts may inhibit the survival and recruitment of ticks. We investigated the potential role of common shrews (Sorex araneus) to serve as a supplementary host source to immature life stages (larvae and nymphs) of a generalist tick Ixodes ricinus and a small mammal specialist tick I. trianguliceps, during decreasing abundances of bank voles (Myodes glareolus). We used generalized mixed models to test whether ticks would have a propensity to parasitize a certain host species dependent on host population size and host population composition across two high‐latitude gradients in southern Norway, by comparing tick burdens on trapped animals. Host population size was defined as the total number of captured animals and host population composition as the proportion of voles to shrews. We found that a larger proportion of voles in the host population favored the parasitism of voles by I. ricinus larvae (estimate = −1.923, p = .039) but not by nymphs (estimate = −0.307, p = .772). I. trianguliceps larvae did not show a lower propensity to parasitize voles, regardless of host population composition (estimate = 0.875, p = .180), while nymphs parasitized shrews significantly more as vole abundance increased (estimate = 2.106, p = .002). These results indicate that common shrews may have the potential to act as a replacement host during periods of low rodent availability, but long‐term observations encompassing complete rodent cycles may determine whether shrews are able to maintain tick range expansion despite low rodent availability.
A real‐time data assimilative forecasting system for animal tracking
Authors: Randon Marine , Dowd Michael , Joy Ruth
Published: April 2022

Monitoring technologies now provide real‐time animal location information, which opens up the possibility of developing forecasting systems to fuse these data with movement models to predict future trajectories. State‐space modeling approaches are well established for retrospective location estimation and behavioral inference through state and parameter estimation. Here we use a state‐space model within a comprehensive data assimilative framework for probabilistic animal movement forecasting. Real‐time location information is combined with stochastic movement model predictions to provide forecasts of future animal locations and trajectories, as well as estimates of key behavioral parameters. Implementation uses ensemble‐based sequential Monte Carlo methods (a particle filter). We first apply the framework to an idealized case using a nondimensional animal movement model based on a continuous‐time random walk process. A set of numerical forecasting experiments demonstrates the workflow and key features, such as the online estimation of behavioral parameters using state augmentation, the use of potential functions for habitat preference, and the role of observation error and sampling frequency on forecast skill. For a realistic demonstration, we adapt the framework to short‐term forecasting of the endangered southern resident killer whale (SRKW) in the Salish Sea using visual sighting information wherein the potential function reflects historical habitat utilization of SRKW. We successfully estimate whale locations up to 2.5 h in advance with a moderate prediction error (<5 km), providing reasonable lead‐in time to mitigate vessel–whale interactions. It is argued that this forecasting framework can be used to synthesize diverse data types and improve animal movement models and behavioral understanding and has the potential to lead to important advances in movement ecology.
Unexpected One‐Pot Formation of Lactam Oximes from Amino‐Hydroxamic Esters
Authors: Lascano Santiago , van der Lee Arie , Lopez Marie
Published: April 2022

The unexpected one‐pot intramolecular formation of lactam oximes from the corresponding amino‐hydroxamic ester in the presence of amine is described. Several reaction parameters were studied, and the importance of the base and the size of the resulting cycle were shown. This reaction can thus be considered as a new synthetic approach to prepare lactam oximes in a one‐pot manner and in mild conditions.
A Photoredox Nozaki‐Hiyama Reaction Catalytic in Chromium
Authors: Calogero Francesco , Potenti Simone , Magagnano Giandomenico , Mosca Giampaolo , Gualandi Andrea , Marchini Marianna , Ceroni Paola , Cozzi Pier Giorgio
Published: April 2022

Organochromium(III) species are multipurpose nucleophiles used in the synthesis of complex organic molecules due to their high functional group tolerance and extraordinary chemoselectivity for aldehydes. The preparation of organochromium(III) species starting from organic halides requires the use of a stoichiometric amount of chromium(II) salts or a catalytic amount of chromium(III) salts in the presence of stoichiometric reductants (such as Mn(0)). Recently, radicals formation from readily available alkenes, followed by their trapping with stoichiometric or catalytic amount of chromium(II) salts were reported in photoredox conditions for the generation of Cr(III) organometallic species. In this paper we disclose a real Nozaki‐Hiyama reaction (NH) in which photoredox conditions enable the preparation of Cr(III) allyl reagents starting from available allyl halides and stable Cr(III) salts.
Quasi Solid‐state Electrolytes of Li2Sn2(bdc)3(H2O)x Metal‐organic Frameworks for Lithium Metal Battery
Authors: Guo Ziwei , He Yuanqin , Zhang Daxu , Lin Yifan , Wen Zuxin , Zheng Zhicheng , Chen Long , Zhang Ning , Liu Xiaohe , Chen Gen
Published: April 2022

Solid‐state electrolytes hold great promise for lithium‐based batteries with high energy density and safety. Here, novel metal‐organic frameworks (MOFs) based composite membranes were fabricated by a rolling process and subsequently employed as quasi solid‐state electrolytes, exhibiting improved ionic conductivity and Li+ transference number as well as stable electrochemical window. Furthermore, the MOF‐based membranes presented a significant effect in modulating the stripping/plating process of Li and resulted in a dendrite‐free Li deposition. The corresponding LiFePO4|Li batteries were assembled and presented improved rate capability and high Coulombic efficiency, offering a new option for MOF‐based electrolytes.
Synthesis and electrochemical performance of in‐situ and ex‐situ carbon‐ coated Na2Ti3O7, as a promising anode for sodium‐ion batteries
Authors: Mukherjee Anwesa , Das Debasish , Banerjee Susanta , Majumder Subhashish Basu
Published: April 2022

Insertion‐type layered Na2Ti3O7 has attracted the attention of the researchers and is considered to be one of the promising low‐voltage anode materiasl for sodium‐ion batteries. In spite of its fascinating electrochemical properties, the low electronic conductivity and structural instability of Na2Ti3O7 are major drawbacks that restrict its practical application. Surface modification with pyrolytic carbon is one of the effective ways to reduce irreversible capacity loss caused by electrolytic degradation. In this work, attempts have been made to investigate the effects of different carbon coating approaches on the electrochemical properties of sol‐gel‐synthesized Na2Ti3O7 microrods. The as‐synthesized Na2Ti3O7 rods are coated with a uniform carbon layer both by in‐situ and ex‐situ methods using citric acid and polyvinyl alcohol as carbon source, respectively. Ex‐situ carbon‐coated Na2Ti3O7 (Na2Ti3O7@C), due to better coating uniformity and higher graphitized carbon percentage, shows enhanced cyclability and rate performance compared to bare material and in‐situ carbon composite (Na2Ti3O7/C). Following the ex‐situ carbonization method using PVA as carbon source, it is found that increase of carbon content from 5wt% to 10wt% significantly improves its electrochemical properties. However, further increase in PVA amount has adverse effect on the cycling as well as rate performance of Na2Ti3O7@C. Surface modified Na2Ti3O7@C with optimum carbon content (10wt% C) shows improved cycling capacity (capacity retention ∼74.75% after100 cycle) and rate performance (∼67 mAhg‐1 at 1.5 Ag‐1). Both excess and inadequate carbon content have detrimental effect on the electrochemical properties of Na2Ti3O7 anode.
Delineating Effluent Exposure and Cumulative Ecotoxicological Risk of Metals Downstream of a Saskatchewan Uranium Mill Using Autonomous Sensors
Authors: Cupe-Flores Beatriz , Mendes Maira , Panigrahi Banamali , Liber Karsten
Published: April 2022

There is increasing interest in using autonomous sensor technology to monitor aquatic ecosystems in real time and in employing such monitoring data to perform better ecological risk assessments. At seven locations in McClean Lake in northern Saskatchewan (Canada) that received diluted uranium milling effluent, we deployed sensor units to track effluent distribution and help predict potential biological effects on aquatic invertebrates. Water was also collected from each location on multiple occasions to measure major ions, dissolved metals, and routine water quality, and sediment was sampled to analyze total metals. The ecotoxicological risk to aquatic invertebrates was estimated using hazard quotients (HQs). The cumulative risk was estimated by summing the individual HQs, and the major ions risk was based on total osmolarity. The results indicated temporal and spatial variations in effluent exposure based on sensor electrical conductivity (EC) measurements in the McClean Lake East Basin. Individual HQs for water ranged from “moderate” (0.40–0.69) to “very high” (greater than 1) for silver, cadmium, arsenic, selenium, mercury, iron, and thallium. At all sites, major ions risk was less than 1. Individual HQs for sediment were “moderate” (0.40–0.69), “high” (0.7–0.99), and “very high” (greater than 1) for vanadium and cadmium. The cumulative risk in water and sediment for all metals combined was greater than 1 at some sites in Vulture Lake (which discharged into McClean Lake) and in McClean Lake itself. A more detailed estimation of the risks for aqueous selenium and arsenic (the only two metals that had good correlation with sensor EC data) indicated that their 90th percentile HQ values were less than 1 in McClean Lake, suggesting that these contaminants of concern do not represent a significant direct risk to aquatic invertebrate communities. Environ Toxicol Chem 2022;41:1765–1777. © 2022 SETAC
Electrodeposition: An efficient method to fabricate self‐supported electrodes for electrochemical energy conversion systems
Authors: Kim Junhyeong , Kim Hyunki , Han Gyeong Ho , Hong Seokjin , Park Juhae , Bang Junbeom , Kim Soo Young , Ahn Sang Hyun
Published: April 2022

The development of electrocatalysts for energy conversion systems is essential for alleviating environmental problems and producing useful energy sources as alternatives to fossil fuels. Improving the catalytic performance and stability of electrocatalysts is a major challenge in the development of energy conversion systems. Moreover, understanding their electrode structure is important for enhancing the energy efficiency. Recently, binder‐free self‐supported electrodes have been investigated because the seamless contact between the electrocatalyst and substrate minimizes the contact resistance as well as facilitates fast charge transfer at the catalyst/substrate interface and high catalyst utilization. Electrodeposition is an effective and facile method for fabricating self‐supported electrodes in aqueous solutions under mild conditions. Facile fabrication without a polymer binder and controlability of the compositional and morphological properties of the electrocatalyst make electrodeposition methods suitable for enhancing the performance of energy conversion systems. Herein, we summarize recent research on self‐supported electrodes fabricated by electrodeposition for energy conversion reactions, particularly focusing on cathodic reactions of electrolyzer system such as hydrogen evolution, electrochemical CO2 reduction, and electrochemical N2 reduction reactions. The deposition conditions, morphological and compositional properties, and catalytic performance of the electrocatalyst are reviewed. Finally, the prospective directions of electrocatalyst development for energy conversion systems are discussed.
A preconditioned p‐multigrid solution approach for the high‐order flux reconstruction method
Authors: Jourdan Eduardo , Wang Z. J.
Published: April 2022

This article addresses two acceleration techniques in the context of high‐order methods: p‐multigrid and local Mach number preconditioning. The flux reconstruction method is used as the spatial discretization scheme and the flow of interest is modeled by the two‐dimensional Euler and Navier–Stokes equations in both steady and unsteady settings. The Weiss and Smith low Mach number preconditioner is used together with dual time stepping in order to perform unsteady simulations. The p‐multigrid uses the third order explicit Runge–Kutta (RK3) scheme as the smoother and the non‐linear LU‐SGS implicit method as the coarse level solver. The algorithm performance is compared against both the explicit RK3 and the LU‐SGS approaches. The use of the Mach number preconditioning significantly increases the efficiency of the p‐multigrid method. For unsteady simulations, the preconditioner helps with the efficiency of the p‐multigrid with larger physical time steps. In most cases, the preconditioned p‐multigrid approach is comparable to or faster than the implicit LU‐SGS algorithm and requires less memory, specially for schemes.
Physics‐informed neural network applied to surface‐tension‐driven liquid film flows
Authors: Nakamura Yo , Shiratori Suguru , Takagi Ryota , Sutoh Michihiro , Sugihara Iori , Nagano Hideaki , Shimano Kenjiro
Published: April 2022

A physics‐informed neural network (PINN), which has been recently proposed by Raissi et al. [J Comput Phys. 2019;378:686–707], is applied to the partial differential equation (PDE) of liquid film flows. The PDE considered is the time evolution of the thickness distribution owing to the Laplace pressure, which involves fourth‐order spatial derivative and fourth‐order nonlinear term. Even for such a PDE, it is confirmed that the PINN can predict the solutions with sufficient accuracy. Nevertheless, some improvements are needed in training convergence and accuracy of the solutions. The precision of floating‐point numbers is a critical issue for the present PDE. When the calculation is executed with a single precision floating‐point number, the optimization is terminated due to the loss of significant digits. Calculation of the automatic differentiation dominates the computational time required for training and becomes exponentially longer with increasing order of derivatives. By splitting the original fourth‐order single PDE into lower‐order coupled PDEs, the computational time for each training iteration is greatly reduced. The sampling density of training data also significantly affects training convergence. For the problem considered in this study, improved convergence was obtained by allowing the sampling density of training data to be greater in earlier time ranges, where the rapid flattening of the thickness occurs.
Petrogenesis and geodynamic significance of Late Triassic mafic microgranular enclaves and its host granodiorite in the Shuanghu area, central Qiangtang
Authors: Xie Linze , Lu Rukui , Huang Yuanyi , Liu Kui , Nan Guowei
Published: April 2022

The genesis of Late Triassic granitoids in the central Qiangtang is significant for deducing the evolution of the Palaeo‐Tethys Ocean in Qiangtang Block. Herein, we present a comprehensive study of zircon U–Pb ages, whole‐rock geochemistry and zircon Lu–Hf isotopes for the mafic microgranular enclaves (MMEs) and host granodiorites from the Shuanghu area, in order to evaluate their petrogenesis and geodynamic implications. New zircon U–Pb dating show identical formation ages for host granodiorites (207.1 ± 2.2 Ma and 206.6 ± 3.8 Ma) and MMEs (205.4 ± 2.9 Ma and 209.2 ± 2.2 Ma). The Shuanghu granodiorites contain amphibole and biotite and are characterized by moderate SiO2 (64.74–66.40 wt%) and K2O contents (2.48–3.62 wt%) as well as low A/CNK (0.69–1.00), indicating I‐type granite affinity. Its enriched zircon Hf isotopes (εHf(t) = −12.04 to −5.09) indicate that they were derived from the ancient mafic lower crust. The MMEs have a similar mineral assemblage, emplacement ages, trace elemental and zircon Hf isotopic compositions with the host granodiorites, indicating the cognate origin. These MMEs represent autoliths captured by latter ascending host magmas in the middle‐upper magma chamber. The highly variable Mg# (37–53), Cr (16.9–190 ppm) and Ni (5.71–67.2 ppm) in the Shuanghu MMEs and host granodiorites indicate that the mantle‐derived magma provided not only the heat but also the mafic components. In combining with previous studies, we suggest that the Shuanghu granodiorites and MMEs were formed in the post‐collision stage, which were caused by the asthenosphere upwelling related to the slab breakoff.
Genetic variants in CYP2B6 and HSD17B12 associated with risk of squamous cell carcinoma of the head and neck
Authors: Liu Hongliang , Li Guojun , Sturgis Erich M. , Shete Sanjay , Dahlstrom Kristina R. , Du Mulong , Amos Christopher I. , Christiani David C. , Lazarus Philip , Wei Qingyi
Published: April 2022

Polycyclic aromatic hydrocarbons (PAH) and tobacco‐specific nitrosamines (TSNA) metabolism‐related genes play an important role in the development of cancers. We assessed the associations of genetic variants in genes involved in the metabolism of PAHs and TSNA with risk of squamous cell carcinoma of the head and neck (SCCHN) in European populations using two published genome‐wide association study datasets. In the single‐locus analysis, we identified two SNPs (rs145533669 and rs35246205) in CYP2B6 to be associated with risk of SCCHN (P = 1.57 × 10−4 and .004, respectively), two SNPs (EPHX1 rs117522494 and CYP2B6 rs145533669) to be associated with risk of oropharyngeal cancer (P = .001 and .004, respectively), and one SNP (rs4359199 in HSD17B12) to be associated with risk of oral cancer (P = .006). A significant interaction effect was found between rs4359199 and drinking status on risks of SCCHN and oropharyngeal cancer (P < .05). eQTL and sQTL analyzes revealed that two SNPs (CYP2B6 rs35246205 and HSD17B12 rs4359199) were correlated with alternative splicing or mRNA expression levels of the corresponding genes in liver cells (P < .05 for both). In silico functional annotation suggested that these two SNPs may regulate mRNA expression by affecting the binding of transcription factors. Results from phenome‐wide association studies presented significant associations between these genes and risks of other cancers, smoking behavior and alcohol dependence (P < .05). Thus, our study provided some insight into the underlying genetic mechanism of head and neck cancer, which warrants future functional validation.
Mendelian randomization analyses of 23 known and suspected risk factors and biomarkers for breast cancer overall and by molecular subtypes
Authors: Chen Fa , Wen Wanqing , Long Jirong , Shu Xiang , Yang Yaohua , Shu Xiao‐Ou , Zheng Wei
Published: April 2022

Many risk factors have been identified for breast cancer. The potential causality for some of them remains uncertain, and few studies have comprehensively investigated these associations by molecular subtypes. We performed a two‐sample Mendelian randomization (MR) study to evaluate potential causal associations of 23 known and suspected risk factors and biomarkers with breast cancer risk overall and by molecular subtypes using data from the Breast Cancer Association Consortium. The inverse‐variance weighted method was used to estimate odds ratios (OR) and 95% confidence interval (CI) for association of each trait with breast cancer risk. Significant associations with breast cancer risk were found for 15 traits, including age at menarche, age at menopause, body mass index, waist‐to‐hip ratio, height, physical activity, cigarette smoking, sleep duration, and morning‐preference chronotype, and six blood biomarkers (estrogens, insulin‐like growth factor‐1, sex hormone‐binding globulin [SHBG], telomere length, HDL‐cholesterol and fasting insulin). Noticeably, an increased circulating SHBG was associated with a reduced risk of estrogen receptor (ER)‐positive cancer (OR = 0.83, 95% CI: 0.73‐0.94), but an elevated risk of ER‐negative (OR = 1.12, 95% CI: 0.93‐1.36) and triple negative cancer (OR = 1.19, 95% CI: 0.92‐1.54) (Pheterogeneity = 0.01). Fasting insulin was most strongly associated with an increased risk of HER2‐negative cancer (OR = 1.94, 95% CI: 1.18‐3.20), but a reduced risk of HER2‐enriched cancer (OR = 0.46, 95% CI: 0.26‐0.81) (Pheterogeneity = 0.006). Results from sensitivity analyses using MR‐Egger and MR‐PRESSO were generally consistent. Our study provides strong evidence supporting potential causal associations of several risk factors for breast cancer and suggests potential heterogeneous associations of SHBG and fasting insulin levels with subtypes of breast cancer.
Trimetazidine, a metabolic modulator, attenuates silica‐induced pulmonary fibrosis and decreases lactate levels and LDH activity in rats
Authors: Abdelrahman Rehab S. , Shawky Noha M.
Published: April 2022

Pulmonary fibrosis has been recently linked to metabolic dysregulation. Silica‐induced pulmonary fibrosis in rats was employed by the current study to explore the effects of trimetazidine (a metabolic modulator‐antianginal drug; TMZ) on silica‐induced pulmonary fibrosis. Pulmonary fibrosis was induced by intranasal instillation of silica (50 mg/100 µl/rat) in TMZ versus vehicle‐treated rats. Body weights of rats, weights of lungs, and wet‐to‐dry lung weights were determined. Various parameters were also measured in serum, bronchoalveolar lavage fluid (BALF) in addition to lung tissue homogenates. Moreover, histopathological examination of sectioned lungs for lesion score and distribution and histochemical detection of myeloperoxidase (MPO) in lung tissues were also performed. No significant differences were observed in body weight gains, lung coefficients, lung weights, and wet‐to‐dry lung weight in silica versus control rats. Elevated lactate levels in serum and lung homogenates were significantly attenuated by TMZ. In addition, lactate dehydrogenase activity, transforming growth factor‐β, and total proteins in BALF were significantly normalized with TMZ. Moreover, TMZ significantly increased reduced glutathione and adenosine triphosphate levels and decreased nitrate/nitrite and hydroxyproline content in lungs of silica‐treated rats. Histopathological examination of lungs revealed more than 56% reduction in lesion score and distribution by TMZ. MPO expression in lungs of silica‐treated rats was also significantly attenuated by TMZ. TMZ attenuates silica‐induced pulmonary fibrosis, an effect that could be mediated by suppressing anaerobic glycolysis‐induced excessive lactate production. Regulation of oxidative stress could also play a role in TMZ‐promoted protective effects.