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the optical regime. [10,11] The capacity of metamaterials for electric field confinement has enabled the realization of a range of physical phenomena in metamaterials, such as electron emission [12] and phase transition in quantum materials. [13] In turn, the electric field enhancement resulting from the near-field confinement leads to nonlinear responses in metamaterials that have been harnessed to enable high harmonic generation, [14] saturable absorption, [15] phase-conjugation, [16] and optical electrifying effects, [17] among other features.In addition to confining the electric field, metamaterials are capable of interacting with and efficiently tailoring the magnetic field. The ability of metamaterials to manipulate the magnetic field has enabled their applications to inductive wireless power transfer, [18] enhancement of the magneto-optic effect, [19] high-quality sensing, [20,21] plasmonic perfect absorption, [22] and magnetic field confinement, [23,24] among others. Another important application of the capacity for magnetic field manipulation is magnetic resonance imaging (MRI), which is the focus herein. For example, negative permeability metamaterials have been employed as waveguides [25] and lenses [26] to image deep tissues using 1.5 Tesla (T) MRI systems and a cylindrical meta-atom has been developed to mitigate the field inhomogeneity in 7 T MRI systems based on the Kerker effect. [27] Recently, judiciously designed metamaterials, consisting of wire [28] or helical resonator arrays, [29] have been utilized to enhance the signal-to-noise ratio (SNR) of the MRI by amplifying the radio-frequency (RF) magnetic field strength due to their capacity for magnetic field enhancement. However, an ongoing limitation of currently available linear metamaterials (LMMs) for enhancing SNR in MRI systems reported to date is their linear nature, resulting in an amplification of the magnetic field during both RF transmission and reception phases in MRI, as shown in Figure 1a. The adoption of an LMM in MRI therefore requires modification of the RF excitation pulses during the transmission phase, [28,29] resulting in undue complications, suboptimal performance, potential safety concerns, and a substantial impediment to clinical adoption.Nonlinear metamaterials (NLMMs) yield an opportunity to construct intelligent and self-adaptive metamaterials in order to selectively enhance the magnetic field during MRI. By leveraging the voltage-dependent capacitance of a varactor diode induced by a reverse-biased p-n junction, [30,31] we developed an NLMM operating at RF frequencies. As opposed

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This study investigates the attitudes and behavioural intentions of community crisis response and tourism community participation in tourist destinations after the occurrence of a disaster. Further, we built a conceptual model of perceived community participation benefit, community attachment, community resilience, and crisis response and community participation intention and measured it using 556 samples surveyed after the Wenchuan earthquake, China. The results indicated that benefit perception, community attachment, and community resilience have a positive effect on crisis response and community participation. The study further reveals that the local tourism community gradually transforms the negative aspects of terrible disasters into development opportunities. Our case study particularly focuses on the initiative shown by and positive participation of the tourist community in the aforementioned transformation. The study proposes the Attachment, Benefit, and Capability framework of tourist community participation based on the crisis response perspective and expands the boundaries of tourist community participation research. The study has theoretical and practical significance, puts forward relevant countermeasures, and has significant implications.