bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anomalous High‐Temperature Superconductivity in YH6
Authors: Troyan Ivan A. , Semenok Dmitrii V. , Kvashnin Alexander G. , Sadakov Andrey V. , Sobolevskiy Oleg A. , Pudalov Vladimir M. , Ivanova Anna G. , Prakapenka Vitali B. , Greenberg Eran , Gavriliuk Alexander G. , Lyubutin Igor S. , Struzhkin Viktor V. , Bergara Aitor , Errea Ion , Bianco Raffaello , Calandra Matteo , Mauri Francesco , Monacelli Lorenzo , Akashi Ryosuke , Oganov Artem R. 
Published: March 2021

AbstractPressure‐stabilized hydrides are a new rapidly growing class of high‐temperature superconductors, which is believed to be described within the conventional phonon‐mediated mechanism of coupling. Here, the synthesis of one of the best‐known high‐TC superconductors—yttrium hexahydride ‐YH6 is reported, which displays a superconducting transition at ≈224 K at 166 GPa. The extrapolated upper critical magnetic field Bc2(0) of YH6 is surprisingly high: 116–158 T, which is 2–2.5 times larger than the calculated value. A pronounced shift of TC in yttrium deuteride YD6 with the isotope coefficient 0.4 supports the phonon‐assisted superconductivity. Current–voltage measurements show that the critical current IC and its density JC may exceed 1.75 A and 3500 A mm−2 at 4 K, respectively, which is higher than that of the commercial superconductors, such as NbTi and YBCO. The results of superconducting density functional theory (SCDFT) and anharmonic calculations, together with anomalously high critical magnetic field, suggest notable departures of the superconducting properties from the conventional Migdal–Eliashberg and Bardeen–Cooper–Schrieffer theories, and presence of an additional mechanism of superconductivity.
Electrically Tunable Singular Phase and Goos–Hänchen Shifts in Phase‐Change‐Material‐Based Thin‐Film Coatings as Optical Absorbers
Authors: Sreekanth Kandammathe Valiyaveedu , Das Chandreyee Manas , Medwal Rohit , Mishra Mayank , Ouyang Qingling , Rawat Rajdeep Singh , Yong Ken‐Tye , Singh Ranjan 
Published: March 2021

AbstractThe change of the phase of light under the evolution of a nanomaterial with time is a promising new research direction. A phenomenon directly related to the sudden phase change of light is the Goos–Hänchen (G–H) shift, which describes the lateral beam displacement of the reflected light from the interface of two media when the angles of incidence are close to the total internal reflection angle or Brewster angle. Here, an innovative design of lithography‐free nanophotonic cavities to realize electrically tunable G–H shifts at the singular phase of light in the visible wavelengths is reported. Reversible electrical tuning of phase and G–H shifts is experimentally demonstrated using a microheater integrated optical cavity consisting of a dielectric film on an absorbing substrate through a Joule heating mechanism. In particular, an enhanced G–H shift of 110 times of the operating wavelength at the Brewster angle of the thin‐film cavity is reported. More importantly, electrically tunable G–H shifts are demonstrated by exploiting the significant tunable phase change that occurs at the Brewster angles, due to the small temperature‐induced refractive index changes of the dielectric film. Realizing efficient electrically tunable G–H shifts with miniaturized heaters will extend the research scope of the G–H shift phenomenon and its applications.
Transition Path Sampling as Markov Chain Monte Carlo of Trajectories: Recent Algorithms, Software, Applications, and Future Outlook
Authors: Bolhuis Peter G. , Swenson David W. H. 
Published: March 2021

AbstractThe development of enhanced sampling methods to investigate rare but important events has always been a focal point in the molecular simulation field. Such methods often rely on prior knowledge of the reaction coordinate. However, the search for this reaction coordinate is at the heart of the rare event problem. Transition path sampling (TPS) circumvents this problem by generating an ensemble of dynamical trajectories undergoing the activated event. The reaction coordinate is extracted from the resulting path ensemble using variants of machine learning, making it an output of the method instead of an input. Over the last 20 years, since its inception, many extensions of TPS have been developed. Perhaps surprisingly, large‐scale TPS simulations on complex molecular systems have become possible only recently. Other important developments include the transition interface sampling (TIS) methodology to compute rate constants, the application to multiple states, and adaptive path sampling. The development of OpenPathSampling and PyRETIS has enabled easy and flexible use and implementation of these and other novel path sampling algorithms. In this progress report, a brief overview of recent developments, novel algorithms, and software is given. In addition, several application areas are discussed, and a future outlook for the next decade is given.
Single‐Unit‐Cell Catalysis of CO2 Electroreduction over Sub‐1 nm Cu9S5 Nanowires
Authors: Yang Deren , Zuo Shouwei , Yang Haozhou , Wang Xun 
Published: March 2021

AbstractAs a bridge between nanocrystal catalysts and single‐atom catalysts, single‐unit‐cell catalysts seem at first glance to be unavailable for catalysis due to quantum effects and synthetic difficulties. Here, 24 nm Cu9S5 nanowires are synthesized via the LaMer pathway. Interestingly, when polyoxometalate (POM) clusters are introduced during the nucleation process, the 0.9 nm Cu9S5 nanowires are finally formed via covalent co‐assembly, analog to A–B–A–B‐type block co‐polymerization in the polymer field (“A” and “B” represent Cu9S5 unit cells and POM clusters, respectively). Multiple characterizations show that Cu9S5 exists as single‐unit‐cell structure. Therefore, each unit cell can work as an isolated active site. The single‐unit‐cell structure exhibits higher electrocatalytic activity and Faradaic efficiency (FE) of formic acid (82.0% at −0.8 V vs reversible hydrogen electrode (RHE)) during CO2 electroreduction, while the nanocrystal structure generates HCOO−, methanol, and ethanol with low FEs. This study suggests that the single‐unit‐cell catalyst displays great potential for precise catalysis by the finite size effect.
How can evolutionary and biological anthropologists engage broader audiences?
Authors: Jones James Holland , Pisor Anne C. , Douglass Kristina G. , Bird Rebecca Bliege , Ready Elspeth , Hazel Ashley , Hackman Joseph , Kramer Karen L. , Kohler Timothy A. , Pontzer Herman , Towner Mary C. 
Published: March 2021

AbstractObjectivesWith our diverse training, theoretical and empirical toolkits, and rich data, evolutionary and biological anthropologists (EBAs) have much to contribute to research and policy decisions about climate change and other pressing social issues. However, we remain largely absent from these critical, ongoing efforts. Here, we draw on the literature and our own experiences to make recommendations for how EBAs can engage broader audiences, including the communities with whom we collaborate, a more diverse population of students, researchers in other disciplines and the development sector, policymakers, and the general public. These recommendations include: (1) playing to our strength in longitudinal, place‐based research, (2) collaborating more broadly, (3) engaging in greater public communication of science, (4) aligning our work with open‐science practices to the extent possible, and (5) increasing diversity of our field and teams through intentional action, outreach, training, and mentorship.ConclusionsWe EBAs need to put ourselves out there: research and engagement are complementary, not opposed to each other. With the resources and workable examples we provide here, we hope to spur more EBAs to action.
Taxonomic diversity ofCebuellain the western Amazon: Molecular, morphological and pelage diversity of museum and free‐ranging specimens
Authors: Porter Leila M. , de la Torre Stella , Pérez‐Peña Pedro , Cortés‐Ortiz Liliana 
Published: March 2021

AbstractObjectivesWe investigated the diversity of the pygmy marmoset,Cebuella pygmaea, by comparing genetic, morphological and pelage traits of animals from Peru and Ecuador.Materials and MethodsWe extracted DNA from museum specimen osteocrusts and from fecal samples collected from free‐ranging individuals. We sequenced the mtDNA cytochromebgene and the control region from samples collected at 13 different sites and used Bayesian inference and Maximum Likelihood to identify distinct clades. We took measurements of the crania of a subset of these specimens (n= 26) and ran a logistic regression to determine if any of the cranial measurements (n= 22) could predict a specimen's clade. In addition, we examined the pelage patterns of the museum specimens and photographs taken of free‐ranging individuals and divided them into pelage types based on coloration of the underbelly.ResultsWe identified two divergent clades, and two distinct groups with clear geographic boundaries within one of those clades. Two measurements of the zygomatic bone perfectly predicted a given individual's mtDNA clade. We found four distinct pelage patterns in our samples, but these patterns are variable within clades and among individuals within the same population.ConclusionThese analyses indicate that the two recognized subspecies of pygmy marmoset should be elevated to the species level (C. pygmaeaandC. niveiventris) based on molecular and cranial differences but not on pelage patterns. We provide evidence on the geographic limits of the two clades and identify regions where additional sampling is required to better define the geographic distribution of the two clades.
Novel method for coke optical texture measurement and application on coke derived from different ranks of coking coal
Authors: Sun Weizhou , Zheng Mingdong , Cui Ping , Hu Desheng , Kan Xiu 
Published: March 2021

AbstractThe optical texture of coke is undoubtedly one of the important factors that determined many properties of coke, but it still mostly depends on the skills and experience of manual analysis. In this paper, a novel automatic measurement method is proposed for coke optical texture. this method through two analyzer angle images(10° and 170°) under polarizing microscope to recognize isochromatic regions which occurs color changed between blue and red by image processing, then characterize the dimensional sizes of isochromatic regions and classify them into different anisotropic texture type. Two fitted ellipse methods are used to characterize the regions' dimensional sizes by the range of shape factorS, followed by classifying different types of anisotropic texture according to the long and short axes of fitted ellipse. An automatic image acquisition and analysis system is established based on the above method. Finally, eight coke samples derived from different ranks of coking coal were selected to test the proposed method. The result shows that it can effectively recognize different types of anisotropic texture and provide composition of different anisotropic texture type for each coke. Moreover, the anisotropic degree of coke shows a significant positive correlation with parent coal rank and a negative correlation with coke reactivity index (CRI).
Potential natural polymer‐based nanofibres for the development of facemasks in countering viral outbreaks
Authors: Shanmugam Vigneshwaran , Babu Karthik , Garrison Thomas F. , Capezza Antonio J. , Olsson Richard T. , Ramakrishna Seeram , Hedenqvist Mikael S. , Singha Shuvra , Bartoli Mattia , Giorcelli Mauro , Sas Gabriel , Försth Michael , Das Oisik , Restás Ágoston , Berto Filippo 
Published: March 2021

AbstractThe global coronavirus disease 2019 (COVID‐19) pandemic has rapidly increased the demand for facemasks as a measure to reduce the rapid spread of the pathogen. Throughout the pandemic, some countries such as Italy had a monthly demand of ca. 90 million facemasks. Domestic mask manufacturers are capable of manufacturing 8 million masks each week, although the demand was 40 million per week during March 2020. This dramatic increase has contributed to a spike in the generation of facemask waste. Facemasks are often manufactured with synthetic materials that are non‐biodegradable, and their increased usage and improper disposal are raising environmental concerns. Consequently, there is a strong interest for developing biodegradable facemasks made with for example, renewable nanofibres. A range of natural polymer‐based nanofibres has been studied for their potential to be used in air filter applications. This review article examines potential natural polymer‐based nanofibres along with their filtration and antimicrobial capabilities for developing biodegradable facemask that will promote a cleaner production.
Intelligent injection molding: Parameters self‐learning optimization using iterative gradient‐approximation adaptive method
Authors: Dong Zhengyang , Zhao Peng , Zheng Jianguo , Ji Kaipeng , Chen Yuhong , Fu Jianzhong 
Published: March 2021

AbstractIntelligent injection molding consists of three aspects: intelligent parameter optimization, process monitoring and control. The optimal process parameters are critical to guarantee product quality. Injection molding is a typical batch process and has the property that previous runs can provide feedback to optimize subsequent runs. This study proposes a self‐learning parameter optimization method named iterative gradient‐approximation adaptive optimization (IGAO) method, which adopts the batch‐to‐batch information to remove the need to establish optimization model with large numbers of experiments. The analysis and the optimization of the parameters can be performed simultaneously. The IGAO method approximates the gradient iteratively and assigns an adaptive step size to each parameter according to gradient accumulation. The experiments conducted in both simulation software and injection molding machine prove that the method has fast convergence speed. Standard product weight can be obtained within 11 runs from three different starting process parameters. Experiment results show that 25% less steps are needed compared with the traditional gradient descent method. The method also has good stability to resist disturbances during the optimization procedure. In general, the proposed IGAO method is fast, stable and robust, and it has good prospects for parameter optimization in batch processes.
Global formation control of nonholonomic unicycle vehicles with guaranteed rate of convergence
Authors: Zhao Yixin , Huang Wei , Liu Yupei , Luo Shiyu , Xie Wenjing 
Published: March 2021

AbstractThis paper studies the full‐state formation control problem of multiple nonholonomic unicycle vehicles. Firstly, the formation error model is transformed into standard nonholonomic chained form, including orientation and position error subsystems. For orientation subsystem, an angular velocity control law is designed to be a cooperative term plus an exponential decay function of time, ensuring orientations reach an agreement on a common value. For position error subsystem, a time‐varying output‐like variable is carefully constructed to ensure a stable zero dynamics, that is, the consensus of these output variables guarantees position formation, overcoming the intrinsic underactuated control difficulty. Then, a linear velocity control law is derived to realize consensus of outputs. It is proved that the proposed distributed time‐varying controller is capable of steering the vehicles to globally exponentially make into desired geometric position shape with the same orientations and vanishing velocities, provided that the communication topology is directed and having a spanning tree. The calculated convergence rates are shown dependent on controller coefficients; thus, the controller is modified to additionally reach a prescribed rate of convergence by redesigning conditions of controller parameters. Finally, two numerical simulations are implemented for five unicycle vehicles, demonstrating the effectiveness of the proposed control scheme.
Robust smooth control for global uniform asymptotic stabilization of underactuated surface vessels with unknown model parameters
Authors: Xie Wenjing , Ma Baoli , Fernando Tyrone , Huang Wei , Zhao Yixin 
Published: March 2021

AbstractThis paper investigates how to design controllers to stabilize the underactuated surface vessel to desired constant location and orientation with vanishing velocities. The first control law is designed as a smooth function of position and orientation errors without using model parameters, where a gain is made time‐varying to get over the nonholonomic constraint on model. Skew‐symmetric and damping terms in model are exploited to help construct two particular Lyapunov functions, and Barbalat's lemma are combined to verify the global uniform asymptotic convergence of errors and velocities. Then, the second and the third control laws are devised as the forms of the first controller plus velocity feedbacks and can achieve the same stability as the first one but have a weaker gain condition. All the three controllers are robust to model parameters due to their absence in controllers and only require three model parameters' upper/lower bounds, decreasing the identification workload greatly. Moreover, they are the first smooth ones capable of achieving global uniform asymptotic full‐state stabilization control of vessel with unknown model parameters. Effectiveness of the proposed controllers is demonstrated by numerical simulations.
Record‐breaking daily rainfall in the United Kingdom and the role of anthropogenic forcings
Authors: Christidis Nikolaos , McCarthy Mark , Cotterill Daniel , Stott Peter A. 
Published: March 2021

AbstractThe breaking of the United Kingdom's daily rainfall record in October 2020 made a striking addition to the list of recent heavy precipitation events in the country. Mounting evidence from attribution research suggests that such extremes become more frequent and intense in a warming climate. Although most studies consider extreme events in specific months or seasons, here we investigate for the first time how extremes of the wettest day of the year may be influenced by anthropogenic forcings. Data from large multimodel ensembles indicate that the moderate historical trend towards wetter conditions will emerge more strongly in coming decades, while a notable anthropogenic influence on the variability of the wettest day may be identified as early as the 1900s. Experiments with different forcings are employed to estimate the changing probability of extremes due to anthropogenic climate change in a risk‐based attribution framework. We introduce a new methodology of estimating probabilities of extremes in the present and future that calibrates data from long simulations of the preindustrial climate to the mean state and variability of the reference climatic period. The new approach utilises larger samples of rainfall data than alternative methods, which is a major advantage when analysing extremely rare events. The record rainfall of the wettest day in year 2020 is estimated to have become about 2.5 times more likely because of human influence, while its return time, currently about 100 years, will decrease to only about 30 years by 2100. Compared to a hypothetical natural climate, we estimate a 10‐fold increase in the chances of such extreme rainfall events in the United Kingdom by the end of this century, which underlines the need for effective adaptation planning.
Surface engineered iron oxide nanoparticles as efficient materials for antibiofilm application
Authors: Velusamy Palaniyandi , Su Chia‐Hung , Kannan Kiruba , Kumar Govindarajan Venkat , Anbu Periasamy , Gopinath Subash C.B. 
Published: March 2021

ABSTRACTOveruse of antibiotics has led to the development of multidrug‐resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic‐resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms in presence of an external magnet. In this review, a detailed description of surface‐engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review.
Sample size optimization and initial allocation of the significance levels in group sequential trials with multiple endpoints
Authors: Gou Jiangtao 
Published: March 2021

AbstractWe consider multistage tests of multiple hypotheses under a flexible setting of calendar time and information fraction, focusing on the case where there are two hypotheses under testing. Explicit expressions of statistical powers are derived. With a proof of existence and uniqueness of solution, we develop a numerical method to search the optimal sample size. The proposed method allows us to find the suitable allocation of initial significance level along with the minimum sample size for group sequential designs, with and without hierarchical structures among different endpoints.
TSH adenoma and syndrome of resistance to thyroid hormones—Two cases report of syndrome of inappropriate secretion of thyrotropin
Authors: Deng Fang , Yang Ze‐yu , Zhang Yu‐ping , Wang Yu‐lin , Hu Jiong‐yu , Zhang Fan 
Published: March 2021

AbstractSITSH (syndrome of inappropriate secretion of thyrotropin) is a rare clinical state defined as uninhibited serum thyroid stimulating hormone in the presence of elevated thyroid hormone. This state is complicated and mainly caused by the abnormal feedback of hypothalamus–pituitary thyroid axis. The TSH adenoma (TSH‐oma) and resistance to thyroid hormones (RTH) are the main etiologies of SITSH. As is well known that the treatment strategies of RTH and TSH‐oma are apparently different, thus identifying the difference between RTH and TSH‐oma is of great significance for the diagnosis and treatment of SITSH.Case descriptionA 62‐year‐old man with a state of elevated thyroid hormones and inappropriate elevated serum TSH level was hospitalized in 2016. Results of the pituitary enhanced magnetic resonance imaging and the somatostatin test respectively demonstrated a space‐occupying lesion of pituitary and an elevated serum sex hormone binding globulin (SHBG) and inhibited TSH secretion, which indicated the occurrence of TSH‐oma. In 2019, a 23‐year‐old girl with a state of elevated thyroid hormones and inappropriate normal serum TSH was hospitalized. Interestingly, whole exome sequencing detection suggested a pathogenic mutation in thyroid hormone receptor β (THRB) gene, which has been shown to be associated with RTH.ConclusionsThe difference between TSH‐oma and RTH ought to be clarified for their accurate diagnose and treatment. The clinical experiences of the two cases reported here suggest that more detail information such as family medical history, serum SHBG level, and THRB gene test is helpful for the diagnose and treatment of TSH‐oma and RTH. Additionally, we also summarized the identification points, diagnosis process, and treatment strategies for these two rare diseases.