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The microenvironments of metal single‐atoms (SAs) have important effects on their physicochemical properties. However, the understanding of the relationship between the coordination configuration of SAs and their properties is insufficient. Here, a sacrificing template strategy is developed to anchor La‐SAs on interconnected graphene nanocages (La‐N‐Cl/GNC), where La‐SAs are located above the graphene plane and one La atom coordinated with four N atoms in the graphene plane and with one Cl atom along the axial direction. Theoretical calculations demonstrated that asymmetrically La‐SAs are more conducive to breaking local charge symmetry. Consequently, additional electrical dipoles along the axial direction are generated, leading to unprecedented dipolar polarization loss and strong electromagnetic wave absorption properties. Moreover, the film constructed by asymmetrically‐coordinated La‐N‐Cl/GNC with a mass density of 0.084 g cm−3 exhibits superior flexibility, excellent mechanical strength, and moderate thermal insulation properties, guaranteeing its practical applications in harsh environments. These findings not only shed light on the relationships between asymmetrically coordinated SAs and their dielectric properties at the atomic level but also provide an efficient method for preparing multifunctional films. [ABSTRACT FROM AUTHOR]

The kinetics and durability of conversion‐based anodes greatly depend on the intrinsic stress regulating ability of the electrode materials, which has been significantly neglected. Herein, a stress dissipation strategy driven by multi‐interface built‐in electric fields (BEFs) and architected structure, is innovatively proposed to design ultrafast and long‐term sodium ion storage anodes. Binary Mo/Fe sulfide heterostructured nanorods with multi‐interface BEFs and staggered cantilever configuration are fabricated to prove our concept. Multi‐physics simulations and experimental results confirm that the inner stress in multiple directions can be dissipated by the multi‐interface BEFs at the micro‐scale, and by the staggered cantilever structure at the macro‐scale, respectively. As a result, our designed heterostructured nanorods anode exhibits superb rate capability (332.8 mAh g−1 at 10.0 A g−1) and durable cyclic stability over 900 cycles at 5.0 A g−1, outperforming other metal chalcogenides. This proposed stress dissipation strategy offers a new insight for developing stable structures for conversion‐based anodes. [ABSTRACT FROM AUTHOR]

Aiming at the problems of long reaction time and the risk of explosion polymerization of acrylate resin, a small amount of ferrocene (Fc) is added to the existing dibenzoyl peroxide (BPO)/N,N‐dimethylaniline (DMA) initiators, and the compound redox initiators (BPO/DMA/ (Fc)) are proposed for acrylate resin polymerization at room temperature. The effect of the content of Fc in the resin on the reaction efficiency and the molding quality of products is researched, and the initiation mechanism of the compound redox initiators is analyzed. It is found that with the addition of Fc, the reaction time of the resin can be shortened by 68% at maximum, the heat release temperature of the resin can be reduced by 40% at maximum, the molecular weight of the reaction products can be increased by 74% at maximum, the tensile and bending properties of the resin castings are increased by 23% and 35% at maximum, respectively, and the bending strength and bending modulus are increased by 57% and 27% at maximum, respectively. The compound redox initiators proposed in this paper can improve the molding efficiency and quality of the product, lay a foundation for the application of acrylic resin in the field of pultrusion molding, perfusion molding, and other in situ molding of thermoplastic composites. [ABSTRACT FROM AUTHOR]

Efficient solar energy utilization technologies are expected to promote the development of a carbon‐neutral and renewable energy society. Photovoltaic cells (PVs) have played an important role in the harvest and conversion of solar energy. Due to the intermittent instability of solar energy, however, PVs must be connected with energy storage systems (EESs). Newly developed photoelectrochemical energy storage devices (PESs) are proposed to directly convert solar energy into electrochemical energy. Initial PESs focused on the external and internal integration of PVs and EESs. However, the voltage mismatch between PVs and EESs leads to massive energy loss and unsatisfactory overall performances of PESs. PESs using dual‐functional photoactive materials (PAMs), which have simplified device configuration, decreased costs, and external energy loss, have recently emerged for realization of solar‐to‐electrochemical‐energy conversion and storage in a single device. The review summarizes the designing concepts, integrated configurations, and overall performances of different types of PESs, particularly PESs utilizing dual‐functional PAMs. Based on the classifications, working principles, basic requirements, and design principles, this review discusses various types of PESs cathodes. Finally, some perspectives are provided for further developing excellent performances of PESs. [ABSTRACT FROM AUTHOR]

In alkaline seawater electrolysis, the oxygen evolution reaction (OER) is greatly suppressed by the occurrence of electrode corrosion due to the formation of hypochlorite. Herein, a catalyst consisting of MoC nanowires modified with NiFe alloy nanoparticles (NiFe/MoC) on nickel foam (NF) is prepared. The optimized catalyst can deliver a large current density of 500 mA cm−2 at a very low overpotential of 366 mV in alkaline seawater, respectively, outperforming commercial IrO2. Remarkably, an electrolyzer assembled with NiFe/MoC/NF as the anode and NiMoN/NF as the cathode only requires 1.77 V to drive a current density of 500 mA cm−2 for alkaline seawater electrolysis, as well as excellent stability. Theory calculation indicates that the initial activity of NiFe/MoC is attributed to increased electrical conductivity and decreased energy barrier for OER due to the introduction of Fe. We find that the change of the catalyst in the composition occurred after the stability test; however, the reconstructed catalyst has an energy barrier close to that of the pristine one, which is responsible for its excellent long‐term stability. Our findings provide an efficient way to construct high‐performance OER catalysts for alkaline seawater splitting. [ABSTRACT FROM AUTHOR]

Exploiting dual‐functional photoelectrodes to harvest and store solar energy is a challenging but efficient way for achieving renewable energy utilization. Herein, multi‐heterostructures consisting of N‐doped carbon coated MoS2 nanosheets supported by tubular TiO2 with photoelectric conversion and electronic transfer interfaces are designed. When a photo sodium ion battery (photo‐SIB) is assembled based on the heterostructures, its capacity increases to 399.3 mAh g−1 with a high photo‐conversion efficiency of 0.71 % switching from dark to visible light at 2.0 A g−1. Remarkably, the photo‐SIB can be recharged by light only, with a striking capacity of 231.4 mAh g−1. Experimental and theoretical results suggest that the proposed multi‐heterostructures can enhance charge transfer kinetics, maintain structural stability, and facilitate the separation of photo‐excited carriers. This work presents a new strategy to design dual‐functional photoelectrodes for efficient use of solar energy. [ABSTRACT FROM AUTHOR]

The achievement of bifunctional metal‐organic frameworks (MOFs) remains a huge challenge due to their lack of dual active sites. Herein, dual sites in the Co‐catecholate (Co‐CAT) are created through Ru, Ir, or Rh doping for overall water splitting. Among them, RuCo‐CAT exhibits excellent bifunctional activities, outperforming benchmarked Pt/C for the hydrogen evolution reaction (HER) and RuO2 for the oxygen evolution reaction (OER). The theoretical calculations demonstrate that the doped Ru atoms with optimal absorption energy for the hydrogen intermediate and the Co centers with a reduced energy barrier for the rate‐determining step are the active sites for HER and OER, respectively. Furthermore, the incorporation of Ru atoms can improve the electrical conductivity and capacity of water adsorption of Co‐CAT greatly, synergistically improving the bifunctional activity. This strategy for engineering dual active sites offers novel insights into designing bifunctional MOFs for overall water splitting. [ABSTRACT FROM AUTHOR]

While extant research shows a curvilinear relationship between aspiration performance gaps and innovation input, we know far less about how vocational experiences of key firm decisions makers may shift this relationship. We propose the concept of executives' vocational socialization and explore how it influences the relationship between firms' aspiration performance gaps and innovation input from the perspectives of the behavioral theory of the firm and upper echelons theory. We theorize that two aspects of executives' vocational socialization, namely, executives' technical career experience and firm tenure, strengthen the inverted U‐shaped relationship between the negative aspiration performance gap and innovation input and weaken the U‐shaped relationship between the positive aspiration performance gap and innovation input respectively. We test these hypotheses using a panel dataset of 1158 listed firms in China from 2008 to 2017, and the empirical results from switching regression and fixed‐effect models support our hypotheses. Our study contributes to research on the aspiration performance gap, innovation input, and behavioral theory of the firm. [ABSTRACT FROM AUTHOR]

Although corporate social responsibility (CSR) activities may facilitate firms to meet stakeholders' demands and gain legitimacy, there is little understanding of whether and how they may bring in harmful consequences such as chief executive officer (CEO) wrongdoing. We developed a framework to explore how CSR activities lead to CEO wrongdoing based on the fraud triangle of pressure, opportunity, and rationalization. Using a sample of 530 listed firms in China that issued CSR reports between 2011 and 2018, we found a positive relationship between CSR participation and CEO wrongdoing. We also found that this positive relationship is strengthened by firms' internal capability to gain profit and their risk orientation. Our study contributes to the CSR literature by examining the potential dark side of CSR activities, and by bridging stakeholder theory and CEO wrongdoing literature. [ABSTRACT FROM AUTHOR]

Nanocarbons with single‐metal atoms (M‐SAs) have displayed considerable potential in various fields of application due to high free energy of M‐SAs and strong metal‐support interaction. However, the uniform dispersion of M‐SAs within the whole carbon matrix still remains a great challenge. Herein, Ni‐SAs are uniformly dispersed within hierarchically porous carbon nanoflowers (Ni‐SA/HPCF) via a spatial confinement of Ni ions within the periodic pores in metal‐organic frameworks (MOFs) with a subsequent carbonization process. The Ni‐SA/HPCF with abundant mesopores and an ultrahigh surface area (1137.2 m2 g−1) exhibits unexpected electromagnetic wave (EMW) absorption property with a minimal reflection loss of –53.2 dB and an effective absorption bandwidth of 5.0 GHz, while the filler ratio in the matrix is merely 10 wt.%. Density functional theory calculations and experimental results reveal that the uniformly dispersed Ni‐SAs break local symmetry of the electronic structure and increase electrical conductivity of host carbon matrix, thereby enhancing the EMW absorption properties. In addition, the unique 3D hierarchical porous morphology boosts the impedance matching property, which synergistically improves the EMW absorption performance of the Ni‐SA/HPCF. This study provides an efficient approach to uniformly disperse M‐SAs within hierarchically porous nanocarbons for EMW absorption and other potential applications. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is a very common cancer among women and one of the primary causes of death in women worldwide. Because BC has different molecular subtypes, the challenges associated with targeted therapy have increased significantly, and the identification of new therapeutic targets has become increasingly urgent. Blocking apoptosis and inhibiting cell death are important characteristics of malignant tumours, including BC. Under adverse conditions, including exposure to antitumour therapy, inhibition of cell death programmes can promote cancerous transformation and the survival of cancer cells. Therefore, inducing cell death in cancer cells is fundamentally important and provides new opportunities for potential therapeutic interventions. Lytic forms of cell death, primarily pyroptosis, necroptosis and ferroptosis, are different from apoptosis owing to their characteristic lysis, that is, the production of cellular components, to guide beneficial immune responses, and the application of lytic cell death (LCD) in the field of tumour therapy has attracted considerable interest from researchers. The latest clinical research results confirm that lytic death signalling cascades involve the BC cell immune response and resistance to therapies used in clinical practice. In this review, we discuss the current knowledge regarding the various forms of LCD, placing a special emphasis on signalling pathways and their implications in BC, which may facilitate the development of novel and optimal strategies for the clinical treatment of BC. [ABSTRACT FROM AUTHOR]

Highly efficient electrocatalysts for the oxygen evolution reaction (OER) are very important for various energy storage and conversion systems such as water splitting devices and metal‐air batteries. However, developing OER electrocatalysts with high activity and excellent stability at a high current density remains a considerable challenge. Herein, a facile room‐temperature‐stirring strategy is described to obtain FeCoNi layered double hydroxide nanocages (FeCoNi‐LDHs) using a metal–organic framework as a precursor. The FeCoNi‐LDHs have hollow features, while their walls are assembled with ultrathin layered hydroxide nanosheets. By designing a unique structure and tuning the composition, high activity and robust long‐term stability of the FeCoNi‐LDHs for the OER outperform IrO2, used as the reference catalyst. The as‐obtained high electrochemically active surface area and the decreased transfer resistance are ascribed to the significantly improved activity. Density functional theory calculations suggest that the introduction of Fe can fine‐tune the electronic structure and decrease the Gibbs free energy difference of the rate‐determining step (ΔG3), improving the intrinsic activity of FeCoNi‐LDHs toward the OER. Furthermore, the proposed room‐temperature‐stirring strategy can be easily scaled up to more than 10 grams of nanocages through a single batch reaction process, demonstrating the large‐scale applicability of the catalysts. [ABSTRACT FROM AUTHOR]

The article titled "Carbon Neutralization" discusses the potential of efficient solar energy utilization technologies to promote the development of a carbon-neutral and renewable energy society. The authors, Zhao, Zhu, and Chen, introduce the recent advances in photoelectrochemical energy storage devices (PESs) that convert solar energy into electrochemical energy. They specifically discuss PESs utilizing dual-functional PAMs, including their design principles, classifications, and reaction mechanisms, as well as their applications in rechargeable devices with gas, liquid, and solid cathodes. The article concludes by providing perspectives for further developing excellent performances of PESs. [Extracted from the article]

This research seeks to contribute to leadership theory by proposing an integrative framework to reveal how servant leadership and employee cognitive factors foster the conditions that promote employee innovative behavior. Building on social cognitive theory, we hypothesize that servant leadership improves employee innovative behavior through inspiring employee knowledge‐sharing. We predict that employee organizational identification strengthens the impact of servant leadership on knowledge‐sharing, and that employee learning goal orientation amplifies the relationship between employee knowledge‐sharing and innovative behavior. We also propose that the positive indirect effect of servant leadership on employee innovative behavior via knowledge‐sharing is strongest when both moderators are at a high level. Using data collected from 215 supervisor‐employee dyads from three private high‐tech firms in China and a multisource and multiphase research design, we find support for our proposed model. Theoretical and managerial implications for leadership and management practices are also discussed. Key points: Servant leadership is positively related to employees' innovative behavior through knowledge‐ sharing.When employees, the relationship between servant leadership and employee knowledge‐sharing can be strengthened.The effects of knowledge‐sharing on innovative behavior can be stronger when employees are highly learning goal oriented.The positive indirect effect of servant leadership on employee innovative behavior via knowledge‐sharing can be strongest when both employee organizational identification and learning goal orientation are at a high level. [ABSTRACT FROM AUTHOR]

To achieve the clinical application of photothermal nanomaterials in tumor treatment, developing photothermal therapeutic agents with a strong photothermal therapeutic effect, good photostability and rapid clearance or dissociation abilities are urgently desired. Herein, epigallocatechin gallate‐iron coordination nanocomplexes with high photothermal conversion capability, magnetic resonance (MR)/photoacoustic (PA) imaging ability and rapid degradation ability under high GSH condition were prepared. (abbreviated as EGCG‐Fe/PVP NCs). The EGCG‐Fe/PVP NCs were composed through a coordination reaction between Fe3+ and EGCG upon the protection of polyvinyl pyrrolidone (PVP). For its application in the biomedical field, using electronegativity from the polyhydroxy characteristics of EGCG, these complexes were controlled to cap the pores of the DOX‐loaded and aminated mesoporous silica nanoparticles via electrostatic attraction to form a multimodal imaging‐guided combined chemo and photothermal therapy nanoplatform (abbreviated as MDEF NPs). The prepared MDEF NPs exhibit high drug loading efficiency and favorable pH‐dependent drug release capacity. In vitro cytotoxicity data showed that MDEF NPs in the laser exposure group exhibited stronger cytotoxicity than other groups. Therefore, this work may expand the application of MSNs and EGCG‐Fe/PVP NCs in the biological field. [ABSTRACT FROM AUTHOR]

Ag2Se quantum dots (QDs) with near‐infrared (NIR) fluorescence have been widely utilized in NIR fluorescence imaging in vivo because of their narrow bulk band gap and excellent biocompatibility. However, most of synthesis methods for Ag2Se QDs are expensive and the reactants are toxic. Herein, a new protein‐templated biomimetic synthesis approach is proposed for the preparation of Ag2Se QDs by employing bovine serum albumin (BSA) as a template and dispersant. The BSA‐templated Ag2Se QDs (Ag2Se@BSA QDs) showed NIR fluorescence with high fluorescence quantum yield (≈21.2 %), excellent biocompatibility and good dispersibility in different media. Moreover, the obtained Ag2Se@BSA QDs exhibited remarkable photothermal conversion (≈27.8 %), which could be used in photothermal therapy. As a model application in biomedicine, the Ag2Se@BSA QDs were used as "gatekeepers" to cap mesoporous silica nanoparticles (MSNs) by means of electrostatic interaction. By taking the advantages of NIR fluorescence and photothermal property of Ag2Se@BSA QDs, the obtained MSN‐DOX‐Ag2Se nanoparticles (MDA NPs) were employed as a nanoplatform for combined chemo‐photothermal therapy. Compared with free DOX and MDA NPs without NIR laser, the laser‐treated MDA NPs exhibited lower cell viability in vitro, implying that Ag2Se@BSA QDs are highly promising photothermal agents and the MDA NPs are potential carriers for chemo–photothermal therapy. From far and NIR: Ag2Se quantum dots with high NIR fluorescence and high photothermal conversion efficiency were synthesized by using a BSA‐templated biomimetic approach. Further, Ag2Se QDs were used as "gatekeeper" in a mesoporous silica nanoparticle drug‐delivery system for chemo–photothermal therapy. [ABSTRACT FROM AUTHOR]

Materials decorated by the hierarchical micro-nanostructures similar to lotus leaf surface topographies are firmly considered to possess the substantial anti-icing functions, showing icing-delay and low ice adhesion. Here, the aim of this work is to verify the anti-icing capacity in the actual icing environment containing supercooled airflow. This study, therefore, develops both routes to fabricate the hierarchical micro-nanostructure and single nanostructure superhydrophobic surfaces, and first evaluates their anti-icing capacity based on the routine measuring strategies in laboratory. Also, the potential application environment is modeled and used to verify their anti-icing performance for further guiding rational design of surface structures of anti-icing materials. Due to the double-scale effect, the hierarchical micro-nanostructure can induce more air pockets to produce the higher hydrophobicity and anti-icing capacity based on the big reference droplets (diameter > 2 mm) and even static water. However, the verified results in the potential application environment demonstrate that the hierarchical micro-nanostructure exhibits the inferior anti-icing performance, comparing with the single nanostructure. The icing area on the single nanostructure surface is almost half of that on the hierarchical micro-nanostructure surface, also causing a reduction of ≈26 g in icing mass. [ABSTRACT FROM AUTHOR]

A noble-metal-free and highly efficient bifunctional catalyst for overall water splitting is greatly desirable to generate clean and sustainable energy carriers such as hydrogen, but enormous challenges remain. Herein, porous interconnected iron-nickel nitride nanosheets are designed and grown on carbon fiber cloth (FeNi-N/CFC); combining a facile electrodeposition method and in situ nitriding process. The as-synthesized FeNi-N/CFC, with a low mass loading of 0.25 mg cm−2, exhibits excellent catalytic activities for both the oxygen evolution reaction (OER) with 20 mA cm−2 at an overpotential ( η) of 232 mV and also the hydrogen evolution reaction (HER) with 10 mA cm−2 at η=106 mV. As a bifunctional electrocatalyst for overall water splitting FeNi-N/CFC only requires a cell voltage of 1.55 V to drive a current density ( j) of 10 mA cm−2 and shows robust long-term durability at j>360 mA cm−2 with a negligible change in current density over 60 h; revealing its promising application in commercial electrolyzers. [ABSTRACT FROM AUTHOR]

A general strategy based on the nanoscale Kirkendall effect has been developed to grow hollow transition metal (Fe, Co or Ni) oxide nanoparticles on graphene sheets. When applied as lithium-ion battery anodes, these hollow transition metal oxide-based composites exhibit excellent electrochemical performance, with high reversible capacities and long-term stabilities at a high current density, superior to most transition metal oxides reported to date. [ABSTRACT FROM AUTHOR]

Charged up: Three‐dimensional architectures constructed from graphene/MoS2 nanoflake arrays have been successfully fabricated by a one‐step hydrothermal method. MoS2 nanoflakes with thicknesses less than 13 nm grow vertically on both sides of graphene sheets (see figure), which allows the architectures to be more stable during charging and discharging. Even at a high current density of 8000 mA g−1, their discharge capacity is still up to 516 mA h g−1. [ABSTRACT FROM AUTHOR]

Based on an analysis of China's current pension system, the present paper indicates that risk control of pension fund management is a serious policy challenge for the Chinese Government. Although some reform efforts have been made, there are still serious institutional and capital market risks that are difficult to overcome but are key in the success of China's pension reform. To ensure a smooth transition in pension reform, China not only needs to build a better institutional framework and facilitate capital market development, but also raise the risk awareness of individual pensioners. [ABSTRACT FROM AUTHOR]

With the current rapid growth of commercial applications for flexible and wearable optoelectronic devices, flexible power sources are very much in demand. Herein, a facile strategy to grow cobalt nanoparticles encapsulated in nitrogen‐doped carbon nanotube arrays on flexible carbon fiber cloth as self‐supported electrodes for high‐performance flexible zinc–air batteries is developed. Benefiting from high electrical conductivity and multiple active sites as well as free polymer binder, the self‐supported electrode exhibits excellent electrocatalytic activity. The maximum power density of a zinc–air battery using the self‐supported electrode as air cathode is higher than that of the zinc–air battery with Pt/C+IrO2 as air electrode. Furthermore, the zinc–air battery can be stably operated under external stress without obvious loss of the electrochemical performance. This work opens up a new pathway for the rational design of flexible electrodes for high‐performance flexible power sources. [ABSTRACT FROM AUTHOR]

Single‐atom (SA) nanozymes have unprecedented physicochemical performance due to their integrated merits of both atomically dispersed metal atoms and bio‐enzymes. However, the structure‐function relationship between the SA nanozyme‐like structure and its dielectric performance is still unclear. Furthermore, controllable synthesis of SA nanozyme‐like structures remains challenging due to their unique five‐coordinated configurations. Here, a dicyandiamide‐mediated pyrolysis strategy is proposed to anchor five nitrogen‐coordinated lanthanum (La)–N5 moieties on interconnected N‐doped graphene nanocages (La‐N5/ING). Theoretical predictions indicate that the spatially coordinated La–N5 moieties exhibit significantly enhanced conduction loss and polarization loss compared to La–N4 moieties, as evidenced by the experimental results. Moreover, the polydimethylsiloxane‐coated chemically cross‐linked film constructed by the La‐N5/ING and aramid nanofibers has outstanding electromagnetic wave (EMW) absorption performance with an effective absorption bandwidth (EAB10) of 6.24 GHz at a thickness of merely 2.0 mm, outperforming those of most reported carbon‐based films. Importantly, the film also has excellent flexibility, hydrophobicity, mechanical strength, and structural stability, ensuring its application potential in practical environments. These findings provide crucial insights into the microscopic environment of SA on the dielectric properties of their host materials, and a critical method for the preparation of multifunctional films with spatial coordinated SA. [ABSTRACT FROM AUTHOR]

High‐performance catalysts are required in various energy storage and conversion systems. In this work, hierarchical Ni‐Fe‐Mo trimetal nitride nanotubes (NTs) as highly efficient, low‐cost, robustly stable, multifunctional catalysts through room‐temperature Fe incorporation and subsequent thermal treatment for full water splitting and Zn‐air batteries are fabricated. The two‐electrode electrolyzer assembled from the NTs delivers a current density of 10 mA cm−2 at 1.513 V, outperforming the precious metal IrO2|Pt couple and state‐of‐the‐art bifunctional catalysts. Furthermore, two all‐solid‐state Zn‐air batteries with the hierarchical NT air cathode in series can power 55 red light‐emitting diodes with excellent operation stability, at the same time as the electrolyzer based on the hierarchical NTs. An alkaline electrolyzer and zinc‐air battery assembled with trifunctional Ni‐Fe‐Mo nitride nanotubes exhibits excellent electrochemical properties. The electrolyzer shows remarkable activity with a current density of 10 mA cm−2 at a voltage of 1.513 V, superior to the Pt and IrO2 couple, and can be self‐powered by the Zn‐air battery with the nanotubes as air‐cathode. [ABSTRACT FROM AUTHOR]

A general strategy based on the nanoscale Kirkendall effect is developed to grow hollow transition metal (Fe, Co or Ni) oxide nanoparticles on graphene sheets. When applied as lithium‐ion battery anodes, these hollow transition metal oxide based composites exhibit excellent electrochemical performance with high reversible capacities and long‐term stabilities at a high current density, superior to most transition metal oxides reported to date. More information can be found in the Full Paper by Y. Chen, C. Sun, P. Gao et al. on page 1638 ff. [ABSTRACT FROM AUTHOR]