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In this paper, we study the following quasilinear Schrödinger-Poisson system in R³ ∫ -Δu + V(x)u + λϕu = f (x, u), x ∈ R³, -Δϕ - ε4Δ4ϕ = λu², x ∊ R³, where λ and ε are positive parameters, Δ4u = div(|∇u|²∇u), V is a continuous and periodic potential function with positive infimum, f (x, t) ∊ C(R³ × R,R) is periodic with respect to x and only needs to satisfy some superquadratic growth conditions with respect to t. One nontrivial solution is obtained for λ small enough and ε fixed by a combination of variational methods and truncation technique. [ABSTRACT FROM AUTHOR]

As a critical step to integrate micro-nano electronic components on the soft substrate, transfer printing allows the facile fabrication of flexible electronics. The key to a successful transfer printing process is to modulate the interfacial adhesion strength at the stamp/device interface. As an advanced approach, electromagnetic-assisted transfer printing explores a sealed chamber with a magnetic stamp film at the bottom that can be reversibly actuated by the externally applied magnetic field. The deflected magnetic stamp film changes the pressure inside the chamber to modulate the interfacial adhesion at the stamp/device interface. Here, we investigate various design considerations and demonstrate a magnetic stamp film with magnetic NdFeB particles dispersed in a silicone polymer. A theoretical model is first established to study the reversible upward (or downward) deformation of the magnetic stamp film in a positive (or negative) magnetic field. The theoretical model reveals the effects of the mass fraction of the magnetic particles, the thickness of the magnetic film, and the magnetic field intensity on the deformation of the film and the transfer printing process. The theoretically predicted linear relationship between the maximum displacement of the magnetic film and the applied magnetic field is validated by finite element analysisand experimental results. [ABSTRACT FROM AUTHOR]

Natural products have been an important source of therapeutic agents and chemical tools. The recent realization that many natural product biosynthetic genes are silent or sparingly expressed during standard laboratory growth has prompted efforts to investigate their regulation and develop methods to induce their expression. Because it is difficult to intuit signals that induce a given biosynthetic locus, we recently implemented a forward chemical-genetic approach to identify such inducers. In the current work, we applied this approach to nine silent biosynthetic loci in the model bacterium Burkholderia thailandensis to systematically screen for elicitors from a library of Food and Drug Administration-approved drugs. We find that β-lactams, fluoroquinolones, antifungals, and, surprisingly, calcimimetics, phenothiazine antipsychotics, and polyaromatic antidepressants are the most effective global inducers of biosynthetic genes. Investigations into the mechanism of stimulation of the silent virulence factor malleicyprol by the β-lactam piperacillin allowed us to elucidate the underlying regulatory circuits. Low-dose piperacillin causes oxidative stress, thereby inducing redox-sensing transcriptional regulators, which activate malR, a pathway-specific positive regulator of the malleicyprol gene cluster. Malleicyprol is thus part of the OxyR and SoxR regulons in B. thailandensis, allowing the bacterium to initiate virulence in response to oxidative stress. Our work catalogs a diverse array of elicitors and a previously unknown regulatory input for secondary metabolism in B. thailandensis. [ABSTRACT FROM AUTHOR]

In this paper, we study the existence of ground state solutions for the following nonlinearly coupled systems of Choquard type with lower critical exponent by variational methods ... Where N ≥ 3, α ∊ (0, N), Iα is the Riesz potential, p, q ∊ (1,√N/n-2 and Np + (N + 2)q < 2N + 4, N+a/N is the lower critical exponent in the sense of Hardy-Littlewood-Sobolev inequality and V ∊ C(RN, (0,∞)) is a bounded potential function. As far as we have known, little research has been done on this type of coupled systems up to now. Our research is a promotion and supplement to previous research. [ABSTRACT FROM AUTHOR]

Wind shear induced by the velocity difference has an important effect on the stably stratified turbulent flow in the atmospheric convective boundary layer (CBL). Cases with different velocity difference are conducted by Large-eddy simulation (LES) to reveal the contribution of shear effect to entrainment. The result shows that the shear-generated turbulent kinetic energy (TKE) in the entrainment layer is partially consumed by the negative buoyancy, which increases the entrainment flux minimum and enhances the entrainment flux ratio in the range of 0.188 - 0.352. Based on the hypothesis of the independence of the shear-generated TKE and buoyancygenerated TKE, an approach for the fraction of the shear-generated TKE available for entrainment is proposed, and the averaged fraction reaches 38.5%, but the evolution tends to increase with the enlargement of velocity difference. [ABSTRACT FROM AUTHOR]

Developing novel nanoparticle-based bioprobes utilized in clinical settings with imaging resolutions ranging from cell to tissue levels is a major challenge for tumor diagnosis and treatment. Herein, an optimized strategy for designing a Fe3O4-based bioprobe for dual-modal cancer imaging based on surface-enhanced Raman scattering (SERS) and magnetic resonance imaging (MRI) is introduced. Excellent SERS activity of ultrasmall Fe3O4 nanoparticles (NPs) was discovered, and a 5 × 10-9 M limit of detection for crystal violet molecules was successfully obtained. The high-efficiency interfacial photon-induced charge transfer in Fe3O4 NPs was promoted by multiple electronic energy levels ascribed to the multiple valence states of Fe, which was observed using ultraviolet-visible diffuse reflectance spectroscopy. Density functional theory calculations were utilized to reveal that the narrow band gap and high electron density of states of ultrasmall Fe3O4 NPs significantly boosted the vibronic coupling resonances in the SERS system upon illumination. The subtypes of cancer cells were accurately recognized via high-resolution SERS imaging in vitro using the prepared Fe3O4-based bioprobe with high sensitivity and good specificity. Notably, Fe3O4-based bioprobes simultaneously exhibited T1-weighted MRI contrast enhancement with an active targeting capability for tumors in vivo. To the best of our knowledge, this is the first report on the use of pure semiconductor-based SERS-MRI dual-modal nanoprobes in tumor imaging in vivo and in vitro, which has been previously realized only using semiconductor-metal complex materials. The non-metallic materials with SERS-MRI dual-modal imaging established in this report are a promising cancer diagnostic platform, which not only showed excellent performance in early tumor diagnosis but also possesses great potential for image-guided tumor treatment. [ABSTRACT FROM AUTHOR]

Team members can experience a range of emotions and to varying degrees. We examine the effects of team emotion diversity on information sharing among team members and, consequently, team performance. By integrating the categorization elaboration model and self-categorization theory, we argue that social class diversity moderates the relationship between team emotion diversity and information sharing. Specifically, we propose that team emotion diversity elicits information sharing when social class homogeneity is high but hinders information sharing when social class homogeneity is low. In addition, we hypothesize that the relationship between information sharing and team performance will be stronger for teams with more, rather than less, social class diversity. To test our propositions, we studied 75 teams enrolled in an Indian master of business administration program, collecting measures of positive and negative affect, information sharing, and team performance at multiple times. Our results mostly support our predictions. We discuss the implications of these findings for team diversity research and for managing diverse teams. [ABSTRACT FROM AUTHOR]

We have predicted extremely high electromagnetic hot spots using the extended-localized coupled surface plasmon resonance configuration. With this unique configuration, we found that an array of particles shows the critical importance of the interparticle gap on the enhancement factor, which was confirmed experimentally using surface-enhanced Raman scattering (SERS). The extended plasmon wave excited in the Kretschmann-Raether configuration propagates on the silver film surface and couples with the gold nanoparticles dispersed on top through excitation of the localized plasmons. A monomolecular layer of 4-aminothiophenol sandwiched between the metal film and the nanoparticles showed an SERS enhancement factor of the order of 1010 per molecule in the hot spots. The configuration was optimized, both by simulations and experiments, with respect to the size of the nanoparticles and the interparticle distances. It is demonstrated that the ultrahigh SERS enhancement does occur only when the extended surface plasmon is coupled to the localized surface plasmon at an optimized interparticle gap. Further, highly sensitive detection of glycerol in ethanol is demonstrated using the optimum structure with a detection limit on the order of 10-12 to the weight percentage of ethanol, which is equivalent to detection of a few molecules. This ultrahigh enhancement is useful in realizing various highly sensitive biosensors when strong enhancement is required as well as in highly efficient optoelectronic and energy devices. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with the multiplicity of nontrivial radial solutions for the following elliptic equation ... where ... and Q are radial positive functions, which can be vanishing or coercive at infinity, f is asymptotically linear or superlinear at infinity. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with the multiplicity of nontrivial radial solutions for the following elliptic equations (P)λ; Δu + V (x)u = λQ(x)|u|q-2 u + Q (x) f (u), x ∈ ℝN; u(x) → 0, as |x| → 1 < q < 2 < λ ∈ ℝ N ≥ 3, V, and Q are radial positive functions, which can be vanishing or coercive at infinity, and f is asymptotically linear at infinity. [ABSTRACT FROM AUTHOR]

Inert dielectric shells coating the surface of metallic nanoparticles (NPs) are important for enhancing the NPs’ stability, biocompatibility, and realizing targeting detection, but they impair NPs’ sensing ability due to the electric fields damping. The dielectric shell not only determines the distance of the analyte from the NP surface, but also affects the field decay. From a practical point of view, it is extremely important to investigate the critical thickness of the shell, beyond which the NPs are no longer able to effectively detect the analytes. The plasmon decay length of the shell-coated NPs determines the critical thickness of the coating layer. Extracting from the exponential fitting results, we quantitatively demonstrate that the critical thickness of the shell exhibits a linear dependence on the NP volume and the dielectric constants of the shell and the surrounding medium, but only with a small variation influenced by the NP shape where the dipole resonance is dominated. We show the critical thickness increases with enlarging the NP sizes, or increasing the dielectric constant differences between the shell and surrounding medium. The findings are essential for applications of shell-coated NPs in plasmonic sensing. [ABSTRACT FROM AUTHOR]

The practical implementation of lithium–sulfur batteries is obstructed by poor conductivity, sluggish redox kinetics, the shuttle effect, large volume variation, and low areal loading of sulfur electrodes. Now, amorphous N‐doped carbon/MoS3 (NC/MoS3) nanoboxes with hollow porous architectures have been meticulously designed as an advanced sulfur host. Benefiting from the enhanced conductivity by the N‐doped carbon, reduced shuttle effect by the strong chemical interaction between unsaturated Mo and lithium polysulfides, improved redox reaction kinetics by the catalytic effect of MoS3, great tolerance of volume variation and high sulfur loading arising from flexible amorphous materials with hollow‐porous structures, the amorphous NC/MoS3 nanoboxes enabled sulfur electrodes to deliver a high areal capacity with superior rate capacity and decent cycling stability. The synthetic strategy can be generalized to fabricate other amorphous metal sulfide nanoboxes. [ABSTRACT FROM AUTHOR]

Surface and interface control is fundamentally important for crystal growth engineering, catalysis, surface-enhanced spectroscopies, and self-assembly, among other processes and applications. Understanding the role of ligands in regulating surface properties of plasmonic metal nanocrystals during growth has received considerable attention. However, the underlying mechanisms and the diverse functionalities of ligands are yet to be fully addressed. In this contribution, we report a systematic study of ligand-mediated interface control in seeded growth of gold nanocrystals, leading to diverse and exotic nanostructures with an improved surface enhanced Raman scattering (SERS) activity. Three dimensional transmission electron microscopy revealed an intriguing gold shell growth process mediated by the bifunctional ligand 1,4-benzenedithiol (BDT), which leads to a unique crystal growth mechanism as compared to other ligands, and subsequently to the concept of interfacial energy control mechanism. Volmer-Weber growth mode was proposed to be responsible for BDT-mediated seeded growth, favoring the strongest interfacial energy and generating an asymmetric island growth pathway with internal crevices/gaps. This additionally favors incorporation of BDT at the plasmonic nanogaps, thereby generating strong SERS activity with a maximum efficiency for a core-semishell configuration obtained along seeded growth. Numerical modeling was used to explain this observation. Interestingly, the same strategy can be used to engineer the structural diversity of this system, by using gold nanoparticle seeds with various sizes and shapes, and varying the [Au3+]/[Au0] ratio. This rendered a series of diverse and exotic plasmonic nanohybrids such as semishell-coated gold nanorods, with embedded Raman-active tags and Janus surface with distinct surface functionalities. These would greatly enrich the plasmonic nanostructure toolbox for various studies and applications such as anisotropic nanocrystal engineering, SERS, and high-resolution Raman bioimaging or nanoantenna devices. [ABSTRACT FROM AUTHOR]

Solutions andweakly compact uniformattractor for the nonautonomous long-shortwave equations with translation compact forces were studied in a bounded domain. We first established the existence and the uniqueness of the solution to the system by using Galerkin method and then obtained the uniformabsorbing set and theweakly compact uniformattractor of the problemby applying techniques of constructing skew product flow in the extended phase space. [ABSTRACT FROM AUTHOR]

The current technical dilemma for gold nanoparticles as photothermal (PT) transducers in cancer therapy is that strong absorption in the second near-infrared (NIR) window is accompanied by strong scattering of the NIR light, which then overrides the absorption, thus significantly weakening the light-to-heat conversion efficiency. Here we successfully prepared spiky gold nanoparticles (spiky Au NPs) with a controlled number of spikes, designed according to our simulations and experimentally verified. Their overall sizes and the numbers, lengths, and widths of the spikes were judiciously adjusted to locate their surface plasmon resonance peaks in the second NIR window and also to achieve a higher absorption-to-extinction ratio. As a result, the spiky Au NPs with optimal size and 6 spikes exhibited a record light-to-heat conversion efficiency (78.8%) under irradiation by 980 nm light. After surface PEGylation and conjugation with a lactoferrin (LF) ligand on the resulting spiky Au NPs, they in vivo displayed long circulation time (blood circulation half-life of ~300 min) and high tumor accumulation due to their larger surface-to-volume ratio. Therefore, spiky Au NPs allowed complete ablation of tumors without recurrence merely after 3 min of light irradiation at 980 nm, opening up promising prospects of cancer photothermal therapy. [ABSTRACT FROM AUTHOR]

We developed a novel method for the real-time monitoring of the delicate change in refractive index (RI) when DNA or RNA hybridize near a DNA-capped silver nanocube (AgNC) surface. This method offers an alternative platform in the quantitative analysis of the trace lung cancer-associated miRNAs in label-free detection. [ABSTRACT FROM AUTHOR]