Max Born and his legacy to condensed matter physics

After a presentation of Max Born's most salient biographical data, we discuss his contributions to science and science policy, with special emphasis on those related to condensed matter physics. Our discussion includes journal articles as well as books. The methodology used is both qualitative and quantitative, including number of items, number of formal and informal citations, and other bibliometric indicators such as the recently proposed Hirsch index (h‐index). The data are mainly based on the Thomson/ISI Web of Science (WoS) which covers a carefully selected set of the more prestigious journals dating back to 1900. Born's books and articles not published in the journals covered by the WoS can also be evaluated, provided they are cited within the WoS journals. Some anecdotic and historical details, which have come to the fore in the course of our bibliometric investigations, are included.     

Multidisciplinary cognitive content of nanoscience and nanotechnology

This article examines the cognitive evolution and disciplinary diversity of nanoscience/nanotechnology (nano research) as expressed through the terminology used in titles of nano journal articles. The analysis is based on the NanoBank bibliographic database of 287,106 nano articles published between 1981 and 2004. We perform multifaceted analyses of title words, focusing on 100 most frequent words or phrases (terms). Hierarchical clustering of title terms reveals three distinct time periods of cognitive development of nano research: formative (1981–1990), early (from 1991 to 1998), and current (after 1998). Early period is characterized by the introduction of thin film deposition techniques, while the current period is characterized by the increased focus on carbon nanotube and nanoparticle research. We introduce a method to identify disciplinary components of nanotechnology. It shows that the nano research is being carried out in a number of diverse parent disciplines. Currently, only 5% of articles are published in dedicated nano-only journals. We find that some 85% of nano research today is multidisciplinary. The case study of the diffusion of several nano-specific terms (e.g., “carbon nanotube”) shows that concepts spread from the initially few disciplinary components to the majority of them in a time span of around a decade. Hierarchical clustering of disciplinary components reveals that the cognitive content of current nanoscience can be divided into nine clusters. Some clusters account for a large fraction of nano research and are identified with such parent disciplines as the condensed matter and applied physics, materials science, and analytical chemistry. Other clusters represent much smaller parts of nano research, but are as cognitively distinct. In the decreasing order of size, these fields are: polymer science, biotechnology, general chemistry, surface science, and pharmacology. Cognitive content of research published in nano-only journals is the closest to nano research published in condensed matter and applied physics journals.     

The Quality of Statistical Reporting and Data Presentation in Predatory Dental Journals Was Lower Than in Non-Predatory Journals

Proper peer review and quality of published articles are often regarded as signs of reliable scientific journals. The aim of this study was to compare whether the quality of statistical reporting and data presentation differs among articles published in ‘predatory dental journals’ and in other dental journals. We evaluated 50 articles published in ‘predatory open access (OA) journals’ and 100 clinical trials published in legitimate dental journals between 2019 and 2020. The quality of statistical reporting and data presentation of each paper was assessed on a scale from 0 (poor) to 10 (high). The mean (SD) quality score of the statistical reporting and data presentation was 2.5 (1.4) for the predatory OA journals, 4.8 (1.8) for the legitimate OA journals, and 5.6 (1.8) for the more visible dental journals. The mean values differed significantly (p < 0.001). The quality of statistical reporting of clinical studies published in predatory journals was found to be lower than in open access and highly cited journals. This difference in quality is a wake-up call to consume study results critically. Poor statistical reporting indicates wider general lower quality in publications where the authors and journals are less likely to be critiqued by peer review.     

Theory of the Coulomb capture of negative mesonic particles

The Coulomb capture of negative mesonic particles is semiclassically calculated in closed form. Expressions are given for energy loss and angular momentum loss, capture ratios, and spectral flux densities of the slow particles in matter. The effect of a centrifugal barrier on the capture ratio and the spectral flux density is shown. Numerical results are given for gaseous Ar and a hypothetical solid of Z = 18 with an assumed atomic radius corresponding to average condensed matter. There is a great difference between the results for the two cases.     

Bibliometric analysis of core journals which publish articles of physical therapy on aging

Objective. Increase in population''s longevity has led to considerable efforts worldwide on physical therapy aging research. The aim of this study is to identify which are the main scientific journals, as well as the most productive authors, institutions and keywords related to the journals, that have published about physical therapy and aging. Methods. Original articles published from 1990 to 2014 were retrieved from the bibliographic database Science Citation Index Expanded of Web of Science Core Collection. After standardization of the bibliographic information, a series of bibliometric indicators was obtained regarding authors, institutions, citation and keywords of the core journals using bibliometric software. The PAJEK network analysis program was used for graphic representation. Results. A total of 2,237 original articles are included in this analysis. The number of identified journals is 573, with an average growth of publishing journals throughout the studied period of 9.41%. Bradford''s distribution shows 12 core journals, out of which 41.67% have published constantly all throughout the 25-year period, being the most productive one Physical Therapy. Fritz, Julie M is the most productive author, and University of Sydney the most productive institution. The keyword exercise is used in an outstanding way. Conclusions. The productivity trends provided an indication of the greater scientific interest of physical therapy in aging as a line of research. Collectively, the data indicated that physical therapy-specific journals are being consolidated but non-specific are still a significant research source, and that a fundamental element of their research includes exercise and movement.     

凝聚态物质中的光声喇曼效应理论

用热弹性理论系统地分析了凝聚态物质的光声喇曼效应,分别导出了连续和脉冲激光泵浦下的光声喇曼信号表达式,并做了数值估算.     

T-duality simplifies bulk–boundary correspondence: the noncommutative case

We state and prove a general result establishing that T-duality, or the Connes–Thom isomorphism, simplifies the bulk–boundary correspondence, given by a boundary map in K-theory, in the sense of converting it to a simple geometric restriction map. This settles in the affirmative several earlier conjectures of the authors and provides a clear geometric picture of the correspondence. In particular, our result holds in arbitrary spatial dimension, in both the real and complex cases, and also in the presence of disorder, magnetic fields, and H-flux. These special cases are relevant both to string theory and to the study of the quantum Hall effect and topological insulators with defects in condensed matter physics.     

Nonlinear planar asymmetrical optical waveguides for sensing applications

This paper provides a theoretical analysis for TE polarized waves guided by a linear film surrounded by two asymmetrical nonlinear media for sensing applications. The sensitivity of the proposed sensor is derived. The conditions required for the sensor to exhibit its maximum sensitivity are presented. This analysis covers the case when the measurand is homogeneously distributed in the covering medium. We show that nonlinear sensors have sensitivities higher than those of linear sensors. The authors believe that optical sensing can be improved by introducing nonlinear waveguides.     

Industrial applications of neutron diffraction

Neutron diffraction (or, to be more general, neutron scattering) is a most versatile and universal tool, which has been widely employed to probe the structure, the dynamics and the magnetism of condensed matter. Traditionally used for fundamental research in solid state physics, this technique more recently has been applied to problems of immediate industrial interest, as illustrated in examples covering the main fields of endeavour.     

Bibliometric Mapping of Literature on High-Entropy/Multicomponent Alloys and Systematic Review of Emerging Applications

High-entropy/multicomponent alloy (HEA/MCA) has received significant research attention in the last decade. There is a dearth of data-driven works dedicated to assessing and visualizing the HEA/MCA literature from a global perspective. To this end, we present the first bibliometric literature analysis of more than 3500 HEA/MCA articles, published between 2004 and 2021, in the Scopus database. We identify the most prolific authors, their collaborators, institutions, and most prominent research outlet. Co-occurrence networks of keywords are mapped and analyzed. A steep rise in research outputs is observed from 2013, when the number of annual publications doubled the previous years. The top five preferred research outlets include Journal of Alloys and Compounds, Materials Science and Engineering A, Scripta Materialia, Intermetallics, and Acta Materialia. Most of these publications emanate from researchers and institutions within China, USA, and Germany, although international scientific collaboration among them is lacking. Research gaps and future research directions are proposed, based on co-occurrence frequencies of author keywords. Finally, a brief systematic review of emerging applications, covering hydrogen storage, additive manufacturing, catalysis, and superconductivity, is undertaken. This work provides an important comprehensive reference guide for researchers to deepen their knowledge of the field and pursue new research directions.     

Pion condensation in neutron star matter: (II). Nuclear forces and stability

This paper presents several stable models of charged-pion condensed neutron star matter. The non-relativistic limit of the chirally symmetric Weinberg Lagrangian is used to describe interactions of the condensed pion field with the nucleons, as well as the pi-pi interactions of the condensed field. In the absence of nucleon-nucleon interactions, matter in this model is unstable, tending to ever-increasing baryon density and condensate wave vector. The connection of this model of condensation with the σ-model is shown.A general framework for including nuclear forces is then laid out. Results are given for a simple model in which the nuclear forces are assumed to produce an interaction energy V(ρ) dependent only on the total baryon density, independent of the degree of pion condensation, and also to produce a constant G-matrix element g in the nucleon-nucleon charge exchange channel. In the absence of condensation the equation of state reduces to that of interacting normal matter. We also consider effects of beta equilibrium and form factors in the p-wave pion-nucleon interaction. The condensed models are stable. Depending on the choice of parameters the models exhibit first- or second-order pion condensation phase transitions, or both.     

Collaboration range: Effects of geographical proximity on article impact

Spatial scientometrics studies how geography influences knowledge creation. In the recent years there has been a surge in this kind of studies, due to the increase of international collaborations. Most of the work in this field has been focused on the geographical distribution of researchers, whilst few have considered how proximity between coauthors influences research quality. In this work we leverage a dataset of geolocalized articles to assess the effect of geographical distance on article impact. More precisely, the dataset, provided by the Observatory of Science and Technology (O.S.T.), consists of roughly 10⁶ scientific articles, gathering all European articles written in 2000 and 2007, spanning 9 disciplines. We evaluate under which geographical extent coauthorships have higher probability of resulting in high impact articles (“high impact” is here approximated by “being in the top 10% most cited articles of its discipline”). We also describe spatial distribution of coauthorship, delineating geographical areas where the production is proportionally higher. The distribution is evaluated both in term of km (as the crow flies), and in terms of administrative partitions (authors’ cities, regions, countries).     

Impact and structure of literature on nanoparticle generation by laser ablation in liquids

The number of publications on laser ablation and nanoparticle generation in liquids increased by the factor of 15 in the last decade, with comparable high impact of the most cited articles in this field. A nearly unlimited variety of nanoparticle material, liquid matrix, and conjugative agent can be combined to a huge variety of colloids within a few minutes of laser processing. However, this diversification makes it hard to identify main research directions without a comprehensive literature overview. This investigation evaluates the impact and structure of the literature in this field tagging most prolific subjects and articles. Using an optimized search algorithm, the data sets derived from Science Citation Index (1998–2008) allow for statements on publication subject clusters, impact of articles and journals, as well as mapping global spots of activities.     

Empirical analysis on a keyword-based semantic system

Keywords in scientific articles have found their significance in information filtering and classification. In this article, we empirically investigated statistical characteristics and evolutionary properties of keywords in a very famous journal, namely Proceedings of the National Academy of Science of the United States of America (PNAS), including frequency distribution, temporal scaling behavior, and decay factor. The empirical results indicate that the keyword frequency in PNAS approximately follows a Zipf’s law with exponent 0.86. In addition, there is a power-low correlation between the cumulative number of distinct keywords and the cumulative number of keyword occurrences. Extensive empirical analysis on some other journals’ data is also presented, with decaying trends of most popular keywords being monitored. Interestingly, top journals from various subjects share very similar decaying tendency, while the journals of low impact factors exhibit completely different behavior. Those empirical characters may shed some light on the in-depth understanding of semantic evolutionary behaviors. In addition, the analysis of keyword-based system is helpful for the design of corresponding recommender systems.     

Factors influencing dB(A) ratings for sound insulation: Incident noise spectrum and shape of the transmission loss curve

A computer study of the influence of both the incident noise spectrum and the shape of the transmission loss curve on dB(A) ratings for assessing acoustical insulation is undertaken in this work. Transmission loss curves are classed into five idealized types suggested by the shapes observed in about 120 actual cases studied at four major laboratories. From them 5875 smoothed transmission loss curves, covering most common walls, were derived and joined to white, pink, traffic, speech, explosive and inversely humped spectrum noises, used as incident noises, to constitute the data base. Values of the incremental insulation ΔTL(A) (excess of dB(A) ratings over the arithmetic mean for a given TL curve) in dB(A) were computed for all possible pairs {TL curve: incident noise}. Computed results of ΔTL(A) grouped according to the incident noise and the idealized shape of the TL curve are presented in three dimensional graphic form. The spectrum of the incident noise and the shape of the transmission loss curve can influence significantly dB(A) ratings of sound insulation. Differences as high as 10 dB(A) can be found for actual cases when the incident noise varies from traffic to white noise. Previous results of various authors, for some discrete cases, are discussed. The convenience of a thorough study of a possible correlation between dB(A) ratings (or other frequency weightings) for acoustical insulation and community response is finally suggested.     

Editorial: An Interesting Comparison Study

While we all know that large-scale facilities such as neutron sources play an important role in condensed matter research, little quantitative characterization of this role is commonly available. As a matter of fact, it could be the subject of a major study-and certain controversy-to define ways and criteria for such a characterization. In discussions between the neutron groups at FZJ (Jülich, Germany), GKSS (Geesthacht, Germany), and HMI (Berlin, Germany), the idea emerged that Physical Review Letters could be used as a reasonable guinea pig for such a study. This high impact journal is familiar to everyone in condensed matter research, so that most people who read such a study could have an opinion on the meaning of statistical data about PRL.