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A multimode antenna for sub‐6 GHz applications in metal‐rimmed mobile terminals is presented. The proposed antenna is composed of a multibranch driven strip, a parasitic grounded strip, and an integrated metal rim that is connected to the ground through two shorting stubs. The proposed antenna occupies a 5‐mm clearance area, featuring simple design without lumped components. The working principle of the antenna is analyzed in detail in terms of its multiple resonant modes and current distributions. The resultant |S11| ≤ −6 dB impedance bandwidth of the antenna covers the LTE 700/2300/2500, UMTS, GSM 850/900, DCS, PCS, and recently proposed n77 to n79 5G NR frequency bands. The prototype of the antenna is fabricated and the design is well validated by experimental results. [ABSTRACT FROM AUTHOR]

Leader–member exchange (LMX) theory has been tested across numerous cultures to determine employee satisfaction and turnover intentions based on the quality of the supervisor–subordinate relationship. Originating as a theory from Western culture, LMX is criticized for its inefficiency in predicting employee satisfaction in collectivist cultures. The purpose of this research was to examine guanxi as a predictor of worker satisfaction, organizational commitment, and turnover intention in the Chinese hotel industry. The results confirmed personal and professional guanxi relationships, distinct from LMX, as antecedents in the causal model. Theoretical contributions from this study included the incorporation of complex Chinese societal norms with the traditional Western LMX model, suggesting a hybridization effect. Practical implications revealed high correlations among LMX, job satisfaction, and organizational commitment in the Chinese hotel industry, demonstrating the critical nature of the supervisor–subordinate relationship in a hospitality organization. [ABSTRACT FROM AUTHOR]

Cardiac arrhythmias occur frequently in patients with acute stroke, with atrial fibrillation (AF) being the most common. Newly detected AF may lead to increased risk of ischemic stroke, which in turn generates stroke recurrence and adverse outcomes. Currently, most studies are focusing on the role of AF in ischemic stroke and attributing cryptogenic ischemic stroke to previously undetected AF. However, in these studies, subjects used to have neither symptoms of palpitation nor evidence of AF. A better understanding of this association will contribute to the management and therapy for patients after clinical decisions regarding stroke patients. Currently, the definition of newly detected AF has not come to an agreement, and the pathophysiology remains incompletely understood, possibly involving complex alterations in both the autonomic network and humoral regulation. Therefore, this review aims to introduce the definition and epidemiology of newly detected AF after stroke with updated information and elucidate the potential pathophysi-ology, such as autonomic imbalance, catecholamine surge, poststroke systematic inflammation, and microvesicles and microRNAs. [ABSTRACT FROM AUTHOR]

Mn3Sn is a noncollinear antiferromagnet which displays a large anomalous Hall effect at room temperature. It is believed that the principal contribution to its anomalous Hall conductivity comes from the Berry curvature. Moreover, dc transport and photoemission experiments have confirmed that Mn3Sn may be an example of a time-reversal symmetry breaking Weyl semimetal. Due to a small, but finite moment in the room temperature inverse triangular spin structure, which allows control of the Hall current with the external field, this material has garnered much interest for next generation memory devices and terahertz spintronics applications. In this work, we report a terahertz range study of randomly oriented Mn3Sn thin films as a function of temperature. At low frequencies, we found that the optical conductivity can be well described by a single Drude oscillator. The plasma frequency is strongly suppressed in a temperature dependent fashion as one enters the 260 K helical phase. This may be associated with partial gapping of the Fermi surfaces, which comes from breaking translational symmetry along the c-axis. The scattering rate shows a quadratic temperature dependence below 200 K, highlighting the possible important role of interactions in this compound. [ABSTRACT FROM AUTHOR]

“Aggressive hospitality” is an emergent phenomenon that is yet to be understood in the tourism field. This phenomenon involves social interaction between hosts and guests that imitates a hospitable encounter, but at the same time fails to demonstrate some characteristic(s) inherent to hospitable behavior. The underlying forces of the phenomenon are traced back to imperialism, high tourism dependence of the developing regions, staged authenticity, and the mutual gaze. The study focuses on two cruise destinations in the Caribbean region and utilizes over 1200 online reviews to construct the meaning of the phenomenon. Theoretical insights and practical implications are provided based on the findings. [ABSTRACT FROM AUTHOR]

As competition among destinations has intensified, researchers have increasingly advocated for a market-oriented approach to destination marketing. Unfortunately, the unique stakeholder structure of the destination marketing environment precludes a direct application of the traditional market orientation paradigm to this domain. Accordingly, the purpose of this research is to empirically develop an operational definition of the market orientation construct that can be applied to destination marketing organizations. Based on the tenets of stakeholder theory, this research proposes a multiple-stakeholder view of the marketing concept and develops its attendant operational construct. Referred to herein as a multistakeholder market orientation (MSMO), this construct is proposed and operationalized as reflective of the extent to which a destination marketing organization (DMO) implements the marketing concept across the stakeholder spectrum. The nomological validity of this construct is established by testing the effect of the proposed MSMO construct on DMO performance. [ABSTRACT FROM AUTHOR]

This study examined the structure and effect of the Full Range Leadership Theory (FRLT) in the context of the China's hotel industry. Empirical tests through data collected from hotels in China indicate that the original western-oriented nine-factor Full Range Leadership Model represented by the Multifactor Leadership Questionnaire (MLQ; Form 5X) is not well supported in China's hotel industry, witnessed by the poor goodness-of-fit indices and the low reliabilities of the factors. Exploratory factor analysis shows that MLQ (Form 5X) can be reduced to a two-factor model in China's hotel industry with the support of much improved goodness-of-fit indices. Test results indicate that cultural and other contextual issues should be considered when applying a theory in a specific industry context. Implications and discussions are provided based on the results of the study. [ABSTRACT FROM AUTHOR]

Travel blogs provide a new way of understanding consumers' perceptions on destination and its associated products. The purpose of this study was to examine international tourists' destination image of China as represented in travel blog discourse. Data were obtained from blog entries relating to trips to China posted on three dominant travel blog websites. Content analysis facilitated by Atlas.ti 6.0 was performed on a total of 89 China-related travel blogs. The study identified the most frequently discussed aspects of tourists' experiences in China. The results also indicated that the blog authors had mixed and paradoxical images of China as identified by previous research. Marketing implications for China's tourism development based on the results were discussed. [ABSTRACT FROM PUBLISHER]

Given the growing competition among golf travel destinations and the increasing costs of managing and maintaining related facilities, it is important to investigate and understand the expenditure patterns of golf travelers. The results of this research provide useful information for golf destination marketers in the development of strategies to attract and retain golf travelers. This study uses an expenditure-based segmentation of golf travelers visiting a Southern Gulf region in the United States. The findings indicate that the heavy spenders exhibit clear spending patterns and are responsible for most of the sample's total expenditures. The heavy spenders also are well differentiated along golfographic and tripographic measures, but not along sociodemographics and information sources used prior to the vacation. The article ends with an assessment of the contributions of the findings both to the literature on travel expenditure and to golf destination marketers. [ABSTRACT FROM AUTHOR]

This study aims to assess the Web-based destination marketing activities employed by American Convention and Visitors Bureaus (CVBs). Empirical data was collected via a survey from 260 CVBs in the USA. The research results reveal that organizational size, financial resources and management team's technological expertise are the dominating factors affecting the effective implementation of each of the four functions of Web-based marketing activities (i.e., information, communication, transaction, and assurance) as well as the overall effectiveness of these activities. The findings suggest that CVBs should use Web-based marketing activities under the guidance of relationship marketing principles. However, the research findings further imply that this is a challenging process which requires investment of considerable resources and organizational support. This study contributes to the body of knowledge by providing empirical evidence on this relatively under researched area. The research findings will be of interest to destination marketing organizations. [ABSTRACT FROM AUTHOR]

At-destination referrals from local experts play a critical and complementary role in information sourcing and venue decision strategies by visitors of a destination. This context-specific form of word-of-mouth communication is widely practiced, yet remains an under-researched phenomenon when taking into consideration the broad range of locals utilized by visitors when making at-destination decisions on travel-related services. Most word-of-mouth studies have examined its influence on consumer's purchase behavior, but few attempts have been made to investigate the local experts' perspective. This exploratory study attempts to contribute to the understanding of the phenomenon from the local experts' perspective from two aspects: (1) examining the nature and significance of at-destination recommendations; and (2) developing and testing a motivational construct of locals making recommendations. The results provide further evidence of a broad range of residents within a community being involved in the provision of venue information and direct property referrals. A test of motivational scale items reveals that five themes emerge as the underlying constructs driving the local experts' referral behavior. Discussion and implications are also provided based on the study results. [ABSTRACT FROM PUBLISHER]

Lithium titanate is a promising anode material for lithium-ion batteries, but its specific capacity and rate performance are low, which restricts its further development. In this paper, by modifying with anchoring carbon particles on the surface, the electrochemical energy storage performance of lithium titanate has been improved at a deeper voltage (0.01–3 V vs. Li+/ Li). The experimental results show that the modified lithium titanate has significant improvement in specific capacity, rate and cycle stability (305.7 mAh g−1 at 0.1 A g−1, 157 mAh g−1 at 5 A g−1, and 245.3 mAh g−1 at 0.1 A g−1 after 800 cycles). Further research found that the improvement of lithium titanate performance is mainly related to a multi-step restore of Ti4+ below 0.6 V, but not to the electrochemical redox of Ti4+/Ti3+ at 1.55 V. This work provided an effective way to promote the comprehensive electrochemical performance of LTO-based materials. Unlabelled Image • Nitrogen-doped carbon nanoparticles • Modified lithium titanate by non-full coverage carbon coating • Effectively improving the rate performance of lithium titanate as Li- battery anode [ABSTRACT FROM AUTHOR]

The present study explores the antecedents of frontline employees' boundary-spanning behaviors in the hospitality industry. Based on social exchange theory and role theory, a conceptual model was built to explore how three dimensions of perceived organizational support (perceived supervisory support, internal communication, and training) cultivate frontline employees' boundary-spanning behaviors through job satisfaction and organizational commitment. Based on the analysis of 597 hospitality frontline employees in the United States, which were recruited through Amazon Mechanical Turk, this study shows the differential impacts of organizational support types on driving boundary spanning staff to effectively operate on the boundary. Theoretical and practical implications of the findings are articulated. [ABSTRACT FROM AUTHOR]

New-onset atrial fibrillation (AF) is frequently observed following acute stroke. The aim of this study was to investigate the effects of the brain-stellate ganglion-atrium network on AF vulnerability in a canine model with acute middle cerebral artery occlusion (MCAO). Twenty-six dogs were randomly divided into the sham-operated group (n = 6), acute stroke (AS) group (n = 7), stellate ganglion ablation (SGA) group (n = 6) and clodronate liposome (CL) group (n = 7). In the sham-operated group, dogs received craniotomy without MCAO. Cerebral ischemic model was established in AS dogs by right MCAO. Right MCAO along with SGA and CL injection into the atrium was performed in SGA and CL dogs, respectively. After 3 days, atrial electrophysiology, neural activity, and the phenotype and function of macrophages in the atrium were studied in all the dogs. Higher AF inducibility (24.4 ± 4.4% versus 4.4 ± 2.2%, P < 0.05) and AF duration (15.7 ± 3.8 s versus 2.6 ± 1.1 s, P < 0.05) were observed in the AS group compared with the sham-operated group, and were associated with increased left stellate ganglion activity, higher macrophage infiltration and higher levels of inflammatory cytokines in the atrium. SGA or CL injection sharply suppressed AF inducibility (5.5 ± 2.7% versus 24.4 ± 4.4%; 5.3 ± 3.2% versus 24.4 ± 4.4%, both P < 0.05) and AF duration (2.9 ± 1.2 s versus 15.7 ± 3.8 s; 3.6 ± 1.0 s versus 15.7 ± 3.8 s, both P < 0.05) in canines with acute stroke. A brain-stellate ganglion-atrium network may increase AF vulnerability through macrophage activation after acute stroke. [ABSTRACT FROM AUTHOR]

A high gain antenna system based on a phase gradient metasurface (PGM) with a four-split ring (FSR) structure is proposed in this letter, which combines the radiation functionalities of transmission-mode, bidirectional-mode, and reflection-mode. The Vivaldi antenna, as a feed source, is placed at the focal point of the metasurface (MS). Then the quasi-spherical wave launched by the feed source undergoes abnormal refraction and reflection when passing through PGM, which proves that the PGM proposed can control the wavefront by altering the frequencies so that the proposed antenna can achieve multimode radiation. In contrast with traditional unidirectional antenna, the proposed antenna has beam converge characteristic in transmission direction at 15.7 GHz with a peak gain of 20.4 dBi, bidirectional radiation at 16.5 GHz, and reflection direction at 17.1 GHz with a peak gain of 16.5 dBi. The results of the simulation and experiment are in good consistency. The proposed PGM has potential applications in designing high-performance multifunctional antennas in communication systems. [ABSTRACT FROM AUTHOR]

This study aims to develop and test a theoretical model that predicts individuals' intention to engage in medical tourism. Structural equation modeling (SEM) was performed to test the study hypotheses by using data collected from 246 US residents. The study results indicated that perceived benefits were positively, and perceived barriers negatively, associated with attitude, and perceived barriers had a negative impact on perceived behavioral control. The study results further revealed that attitude, perceived behavioral control, and subjective norm positively influenced individuals' intention to engage in medical tourism. Finally, a significant moderating effect of perceived severity was found on the relationships between perceived benefits and attitude, perceived barriers and attitude, and attitude and behavioral intention. The findings of the study offer valuable theoretical contributions and practical implications in the context of medical tourism. [ABSTRACT FROM AUTHOR]

A kind of compound optical lens (COL) inspired by metamaterials whose unit cell is a closed symmetric S‐type resonator (CSSR) is designed to enhance the gain and directivity of the antipodal Vivaldi antenna (AVA). COL, composed of a plano‐convex lens and a double‐convex lens, can generate a very narrow beam with a half‐power beamwidth of 11.2° at 12 GHz. Traditional metamaterial lenses can only convert spherical waves into plane waves. Although the gain will increase, the beamwidth of the antenna is still very wide. COL can focus the plane wave transformed from the spherical wave, which makes the radiation beam extremely narrow. The proposed antenna has a −10 dB impedance bandwidth of 169.2% (1.0‐12.0 GHz) and a −3 dB gain bandwidth of 133.3% (2.0‐10.0 GHz) and a maximum gain enhancement of 5 dBi. The experimental results of the antennas agree with the simulation results. The proposed antenna is eventually a suitable candidate for wireless communications and radar applications. [ABSTRACT FROM AUTHOR]

Combined with the resistor loading and capacitive loading technique, a planar printed ellipse antenna is designed to achieve ultra‐bandwidth and upper radiation efficiency. To accomplish loading, four resistor lumps bridge the metallic strip against the antenna arm on the top layer and rectangular conducting cavity. Simulations are performed for various characteristics of the antenna such as current distribution, near‐field radiation pattern and time waveform. Comparison of antenna characteristics between the antenna with resistor loading (type‐I) and the antenna with resistor and capacitive loading (type‐II) is made using simulations and measurements. The proposed antenna is constructed and measured. It is shown that the antenna achieves an ultra‐bandwidth over 8:1 (1–8 GHz) with a return loss less than −10 dB. In addition, experimental verification has been carried out to confirm the improved properties of the antenna. The capacitive loading produced at the end of the antenna arm has improved the peak of the radiation waveform at least 0.62 dB without the cost of increased size. [ABSTRACT FROM AUTHOR]

Perovskite-based aqueous supercapacitors have important development prospects due to their advantages of high energy density, low cost, environmental benignity. Here, bimetallic Ni-Mn and trimetallic Ni-Co-Mn perovskite fluorides are prepared via facile solvothermal method and characterized as positive electrode materials for supercapacitors. The structure, composition, chemical states and the electrochemical properties of these samples are investigated in detail. Three electrode measurements indicate that the electrochemical properties of the perovskite fluorides KNiF 3 depend on the nature and amount of dopants. Partial doping of Ni by Mn increases the rate capability but decreases the specific capacity, while Co and Mn co-doping improve both the rate capability and specific capacity of perovskite fluoride KNiF 3. The K-Ni-Co-Mn-F (Ni/Co/Mn = 12:2:1) sample exhibits the maximum specific capacity of 211 mAh g−1, low internal resistance and a high rate capability (82% capacity retention from 1 to 16 A g−1). Furthermore, the AC//K-Ni-Co-Mn-F (Ni/Co/Mn = 12:2:1) asymmetric supercapacitor delivers a maximum energy density of 50.2 Wh kg−1. These results prove that Co and Mn co-doped KNiF 3 can be a promising material for supercapacitor. [ABSTRACT FROM AUTHOR]

Carbon-based anode materials with unique structure, high electrical conductivity, high Li storage performance and excellent cycling stability are promising alternatives to traditional graphite anode materials in lithium-ion batteries (LIBs). Here we report a flower-like carbon material with hierarchical structure that is prepared by carbonization of a flower-like Zn-based metal-organic framework (MOF). The 2D layered MOF network precursor, namely [Zn(BDC)(MelM)·(DMF)] (BDC = benzene dicarboxylic acid, MelM = 2-Methylimidazole), is constructed using two ligands under solvothermal conditions. As an anode material for LIBs, these carbon nanoflakes exhibit remarkable electrochemical performance (capacity, cyclability, and rate capability); the capacity of 902.5 mAh g−1 was retained after 200 cycles at a current density of 100 mA g−1. The remarkable performance results from the unique morphology of carbon nanoflakes which is beneficial for infiltration of electrolyte and the transportation of Li ions. Image 1 • Preparation of 2D layered metal-organic framework. • Interesting 2D nanostructures of flower-like carbon material. • The kind of anode material for LIBs possess excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

• Shear connectors can be omitted in the PECB. • The PECB under flexure can behave satisfactorily. • Practical models are derived and validated for the PECB. This paper focuses on a new type of composite beam designated as the partially encased cellular beam (PECB). The PECB consists of a steel wide-flange member in which its perforated web is encased by reinforced concrete. The PECB is envisioned to be superior to the conventional partially encased beam in that it can eliminate the need of shear connectors required in the conventional partially encased beam to develop the desired composite action. This feature helps alleviate reinforcement congestion that may exists in a conventional partially encased beam and minimize construction cost and effort. To investigate the flexural behavior of the proposed PECB, five specimens with representative geometries and typical materials were designed and constructed. The specimens were monotonically loaded with the four-point bending test setup. Test results show that the proposed PECB can behave satisfactorily under flexure and that the shear connectors may not be needed in a properly designed PECB for development of the composite action. Based on the classic beam theory and idealized stress/strain diagrams, this paper develops three practical models for estimating the yield flexural strength, plastic flexural strength, and initial flexural stiffness of the proposed PECB. Comparisons of the predictions from these models with the test results show that the practical models can provide reasonable predictions and can be used for future practice. [ABSTRACT FROM AUTHOR]

Review: 92 refs. [ABSTRACT FROM AUTHOR]

Purpose. The aim of this study was to investigate the role of the medium-conductance calcium-activated potassium channel (KCNN4, KCa3.1) in the secretion of proinflammatory exosomes by atrial myocytes. Methods. Eighteen beagles were randomly divided into the sham group (n = 6), pacing group (n = 6), and pacing+TRAM-34 group (n = 6). Electrophysiological data, such as the effective refractory period, atrial fibrillation (AF) induction, and AF duration, were collected by programmed stimulation. Atrial tissues were subjected to hematoxylin and eosin, Masson's trichrome, and immunofluorescence staining. The expression of KCa3.1 and Rab27a was assessed by immunohistochemistry and western blotting. The downstream signaling pathways involved in KCa3.1 were examined by rapid pacing or overexpressing KCNN4 in HL-1 cells. Results. Atrial rapid pacing significantly induced electrical remodeling, inflammation, fibrosis, and exosome secretion in the canine atrium, while TRAM-34 (KCa3.1 blocker) inhibited these changes. Compared with those in control HL-1 cells, the levels of exosome markers and inflammatory factors were increased in pacing HL-1 cells. Furthermore, the levels of CD68 and iNOS in macrophages incubated with exosomes derived from HL-1 cells were higher in the pacing-exo group than in the control group. More importantly, KCa3.1 regulated exosome secretion through the AKT/Rab27a signaling pathway. Similarly, inhibiting the downstream signaling pathway of KCa3.1 significantly inhibited exosome secretion. Conclusions. KCa3.1 promotes proinflammatory exosome secretion through the AKT/Rab27a signaling pathway. Inhibiting the KCa3.1/AKT/Rab27a signaling pathway reduces myocardial tissue structural remodeling in AF. [ABSTRACT FROM AUTHOR]

An optimization method for ultrawideband multiple-input-multiple-output (MIMO) planar array topology design, which can satisfy both uniformity and lower element shadowing principles, is proposed by extending our previous work. Two planar MIMO arrays, namely, the basic optimal array (BOA) and the extended optimal array (EOA) are optimized. The focusing and sidelobe-suppression properties of the BOA and the EOA are demonstrated to be superior to other two previous state-of-the-art planar MIMO arrays. The advantages of the two optimized arrays in 3-D imaging are further indicated by experimental results for different distributed targets. The validity of the proposed method is verified by the excellent performances of the BOA and the EOA. [ABSTRACT FROM PUBLISHER]

Calcite cement is a common type of cementation in tight sandstone reservoirs of the Upper Triassic Yanchang Formation Chang 8 Member in the Zhijing-Ansai area of the Ordos Basin, which has significant influence on reservoir densification and heterogeneity. Calcite cements affect the quality of the reservoir conspicuously. The characteristics and origins of calcite were investigated using a series of approaches from the perspective of petrography and geochemistry, including thin section observation and identification, cathode luminescence, scanning electron microscopy, AMICS analysis, LA-ICP-MS elements analysis, and carbon and oxygen isotopes analysis. The results of all analytical tests indicated that calcite cements can be divided into two types according to their occurrence and origins. Type-I calcite cements mainly occur in sandstone reservoirs near the sandstone–mudstone interface or the sandstone layers adjacent to mudstone. Generally, there is no chlorite coating around them, and they appear dark orange under cathode luminescence. The carbon source of Type-I calcite cements may be related to the compaction and drainage of mudstone. Type-II calcite cements are formed in the early stage, and their carbon source may be related to the compaction and drainage of the adjacent mudstone. Type-II calcite cements are surrounded by chlorite coating primarily present in the interior of fine-grained sandstone, showing as bright yellow under cathode luminescence. Decarboxylation of organic matter in the source rocks may provide a crucial source of carbon for Type-II calcite cements. [ABSTRACT FROM AUTHOR]

The metasurface is a functional film device based on a subwavelength structure, which has a strong light field control ability and has the advantages of ultrathin, low loss, and easy manufacturing. However, realizing a multifunctional metasurface, yet simple enough to design, manufacture, and thin is still a challenge. In this article, we propose a novel metasurface with negligible thickness as a beam splitter, which can achieve half transmission and half reflection of the incident wave at the same frequency. It also controls the polarization of circularly polarized electromagnetic (EM) waves in the transmission mode. A broadband operation can be achieved based on the geometric phase theory, and the phase control can be achieved by azimuth rotation of the structure. The numerical results of the metasurface are in good agreement with the experimental results in the measured frequency range. The ultrathin multifunctional metasurface realized by the geometric phase principle provides an important stepping stone for simple optical devices and can be extended to a higher frequency range. [ABSTRACT FROM AUTHOR]

Mastery over the structure of materials at nanoscale can effectively tailor and control their catalytic properties, enabling enhancement in both activity and durability. We report a size-controlled synthesis of novel Pt-Cu hierarchical trigonal bipyramid nanoframes (HTBNFs). The obtained nanocrystals looked like a trigonal bipyramid on the whole, composed of similar ordered frame structural units. By varying the amount of KI involved in the reaction, HTBNFs with variable sizes from 110 to 250 nm could be obtained. In addition, the structure of HTBNFs could be preserved only in a limited range of the Pt/Cu feeding ratio. Relative to the commercial Pt/C, these Pt-Cu HTBNFs with different Pt/Cu ratio exhibited enhanced electrocatalytic activity toward formic acid oxidation reaction as much as 5.5 times in specific activity and 2.1 times in mass activity. The excellent electrocatalytic activity and better durability are due to the unique structure of HTBNFs and probably synergetic effects between Pt and Cu. [ABSTRACT FROM AUTHOR]

Mastery over the structure of materials at nanoscale can effectively tailor and control their catalytic properties, enabling enhancement in both activity and durability. We report a size-controlled synthesis of novel Pt-Cu hierarchical trigonal bipyramid nanoframes (HTBNFs). The obtained nanocrystals looked like a trigonal bipyramid on the whole, composed of similar ordered frame structural units. By varying the amount of KI involved in the reaction, HTBNFs with variable sizes from 110 to 250 nm could be obtained. In addition, the structure of HTBNFs could be preserved only in a limited range of the Pt/Cu feeding ratio. Relative to the commercial Pt/C, these Pt-Cu HTBNFs with different Pt/Cu ratio exhibited enhanced electrocatalytic activity toward formic acid oxidation reaction as much as 5.5 times in specific activity and 2.1 times in mass activity. The excellent electrocatalytic activity and better durability are due to the unique structure of HTBNFs and probably synergetic effects between Pt and Cu. [ABSTRACT FROM AUTHOR]

Highlights: [•] Disappearance kinetics of pyridaben in cabbage under field condition was studied. [•] Pyridaben residue analysis was carried out by a validated and accredited method. [•] Risk assessment of pyridaben in cabbage was evaluated. [ABSTRACT FROM AUTHOR]

A novel tubular EKG material in electroosmotic field test combined with a vacuum preloading method was first conducted in a reclamation project in Ningbo, China, by using a vertical-layered power technology aiming to improve the drainage effect of the deep soil. The reinforcement effect of this tubular EKG was compared with that of conventional plate EKG by monitoring the strength, water content, settlement, and pore pressure accumulation. Test results show that soil in the tubular EKG treatment area had higher strength, larger settlement, and faster dissipation of pore water pressure. The advantage of the vertical-layered power technology in deep soil reinforcement was demonstrated by test and numerical simulations. Simulations results showed that vertical-layered power technology from bottom to top layers was more effective for deep soil reinforcement due to longer energization time. Theoretical equations and numerical simulations have demonstrated that rather than being due to a larger effective electric field distributed, the superior effect of tubular EKG lies in its larger cross section not being easy clogged. This study demonstrates the advantages of tubular EKG electrodes and vertical-layered power technology in reinforcing deep soil and makes a progressive exploration to expand the application of electroosmosis reinforcement. [ABSTRACT FROM AUTHOR]

This study assessed the mediating effects of destination image on the relationship between travel constraints and intention to visit. Structural equation modeling identified that destination image mediates between travel constraints and intention to visit, and thereby the negative impact of perceived constraints on intention to visit could be alleviated through the mediating effect of destination image. Thus, travelers can find the means to alleviate travel constraints through a negotiation mechanism. The findings provide practical implications for effective destination marketing programs in that the negative impact from travel constraints can, to a great extent, be mitigated. [ABSTRACT FROM PUBLISHER]

The article investigates traditional decision-making choice models and offers a new way of thinking about the tourist vacation-making intricacies. Specifically, this article examines the interrelationship between affect and cognition in the tourist vacation decision-making process and argues that consumers, during each vacation decision-making task, use both affect and cognitive processes in varying degrees depending on their valence and intensity. The traditional view of decision making posits that the consumer is a rational decision maker who proceeds through a series of prescribed steps before finding an optimal decision solution. However, with the growing prominence on the role of affect, 'hot' aspects of cognition in psychology, and neuroscience investigations, much of the traditional cognitive-dominated theories are being reexamined. A tourist decision-making framework is presented demonstrating the proposed theory and provides understanding to the influences that affect and cognition have on the decision-making process. After delineating these concepts, propositions are presented followed by the Discussion and Conclusions section that summarizes and discusses challenges associated with studying affect. [ABSTRACT FROM AUTHOR]

This study explores the consumer experience by examining empirical data collected via a series of in-depth, semistructured interviews with luxury hotel guests. The study findings indicate that hotel guest experiences constitute both physical environment and human interaction dimensions. The research findings suggest that luxury hotel experiences are affected by trip-related factors and personal characteristics of consumers, which impact perceived experience dimensions. The research findings provide specific implications for hotel executives looking for ways to differentiate themselves from their competitors through using experience marketing strategies. In particular, the proposed framework in this study can help practicing managers understand how different factors play a role in consumer experiences. This article contributes to the overall understanding of consumer experience by illuminating the experience perceptions of consumers within the luxury hotel segment. [ABSTRACT FROM AUTHOR]

A compact antipodal Vivaldi antenna (AVA) with metamaterial half-lens (MHL) for beam control is proposed. The proposed AVA has three different beam forms in the operating frequency band, including end beam from 3 GHz to 9 GHz, beam splitting at 12.2 GHz, and beam deflection at 13 GHz. Furthermore, it can perform beam scanning by adjusting operating frequency from 12.7 GHz to 13.5 GHz. The simulation indicates that the proposed AVA has a −10 dB impedance bandwidth of 143.6% (2.3–14.0 GHz) and a −3 dB gain bandwidth of 100% (4.5–13.5 GHz), which is consistent with the experimental results. Besides, the gain of the proposed AVA has an improvement of about 2 dB in the working band. As a new method to control the beam, the loading of MHL realizes the design of a small size and multi-function antenna, which can be widely used in wireless communication systems. [ABSTRACT FROM AUTHOR]

A series of KNiF 3 @carbon nanotubes (CNTs) are synthesized via a facile solvothermal method and applied as supercapacitor electrodes. The addition of carbon nanotubes can significantly overcome the rate capability defect of bare KNiF 3 and improve the specific capacity to a certain extent, which mainly owing to the increase of conductivity and electron/ion transports capacity. In addition, the cross-linked structure of carbon nanotubes and the evenly anchoring of KNiF 3 nanoparticles can increase the stability of the composites. As a result, the optimal candidate KNiF 3 @CNTs-8 (the content of carbon nanotubes is 8 mg and the mass fraction is 1.0%) shows highest specific capacity (821.4 C g−1 at 1 A g−1) and capacity retention (83.6% at 16 A g−1). The asymmetric supercapacitor AC//KNiF 3 @CNTs-8 delivers extremely high energy density of 63.7 Wh kg−1. More importantly, the ASC device shows ultra-long cycling stability, with 95.9% capacity retention after 5000 cycles. These results prove that KNiF 3 @CNTs can be a promising material for supercapacitor. Image 1 • KNiF 3 @CNTs-8 presented high specific capacity and excellent rate capability. • The optimal composite material exhibited high electrical conductivity. • An asymmetric supercapacitor AC//KNiF 3 @CNTs-8 was fabricated and investigated. • The ASC device exhibited ultra-high energy density and excellent cycling life. [ABSTRACT FROM AUTHOR]

Scattering from rice leaves contributes substantially to total vegetation canopy backscattering and detailed knowledge about it is necessary for developing a microwave scattering model. A parabolic curve is generally adopted to simulate the leaf shape but this is rarely incorporated into the calculation of the scattering. In this paper, two specific models, one based on physical optics (PO) approximation and the other on the discrete dipole approximation (DDA), are presented to involve the parabolic leaf curvature effects. Three typical leaves were chosen from 1433 parabolic leaves obtained during ground measurements. The PO and DDA models were used to calculate the leaf scattering. The generalized Rayleigh–Gans (GRG) approximation was also included in the simulation. The method of moments, a computational electromagnetic method, was utilized to evaluate the accuracy of each model. Validation of the models was conducted at incidence angles ranging from 10° to 60°, incidence azimuthal angles ranging from 0° to 360°, and incidence frequencies of 1.2 GHz (L-band), 5.4 GHz (C-band), and 9.65 GHz (X-band). Among the GRG approximation, the DDA model and the PO model, the latter gave the best accuracy −>65% in the cases tested, while the GRG model was the least accurate. The high accuracy of the PO model was maintained at both the low and high frequency bands. The PO model, therefore, has great potential for use to interpret radar measurements from rice fields and other types of vegetation canopy. [ABSTRACT FROM PUBLISHER]

This paper reports a facile fabrication of N-doped graphene quantum dots (N-GQDs) showing controllable chemical properties through a hydrothermal treatment. The N-GQDs have a uniform size of 3.06 ± 0.78 nm and prefer the equilibrium shapes of circle and ellipse due to the minimization of edge free energy. The N/ C atomic ratio in N-GQDs can be precisely tailored in a range from 8.3 at% to 15.8 at% by simply controlling the concentration of N source (ammonium hydroxide). One order of magnitude quantum yield of 34.5% is achieved by N-GQDs, compared with the N-free GQDs, as the substitutional N has an essential role in more effective radiative emission. Excessive N dopants in N-GQDs can lead to photoluminescence quenching, through nonradiative transition back to the ground state. The N-GQDs are further found to be suitable as photocurrent conversion materials due to benign energy matching with anatase nanofibers, the ultrafast electron injection at their interface, and efficient electron transfer. This work provides an efficient and inspiring approach to engineering both chemical components and physical properties of N-GQDs, and will therefore promote their basic research and applications in energy conversion. [ABSTRACT FROM AUTHOR]

Yunqian Dai and co‐workers report on page 597 how N dopants are tailored in the form of both substitutional and pyrrolic N in graphene quantum dots (N‐GQDs), showing controllable chemical properties. The substitutional N leads to significantly modified photoluminescence properties of the versatile N‐GQDs, which also exhibit highly efficient photocurrent conversion abilities when supported by anatase nanofibers. [ABSTRACT FROM AUTHOR]