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Heterostructures with a rich phase boundary are attractive for surface-mediated microwave absorption (MA) materials. However, understanding the MA mechanisms behind the heterogeneous interface remains a challenge. Herein, a phosphine (PH3) vapor-assisted phase and structure engineering strategy was proposed to construct three-dimensional (3D) porous Ni12P5/Ni2P heterostructures as microwave absorbers and explore the role of the heterointerface in MA performance. The results indicated that the heterogeneous interface between Ni12P5 and Ni2P not only creates sufficient lattice defects for inducing dipolar polarization but also triggers uneven spatial charge distribution for enhancing interface polarization. Deutivacaftor Furthermore, the porous structure and proper component could provide an abundant heterogeneous interface to strengthen the above polarization relaxation process, thereby greatly optimizing the electromagnetic parameters and improving the MA performance. Profited by 3D porous heterostructure design, P400 could achieve the maximum reflection loss of -50.06 dB and an absorption bandwidth of 3.30 GHz with an ultrathin thickness of 1.20 mm. Furthermore, simulation results confirmed its superior ability (14.97 dB m2 at 90°) to reduce the radar cross section in practical applications. This finding may shed light on the understanding and design of advanced heterogeneous MA materials.Although back-surface passivation plays an important role in high-efficiency photovoltaics, it has not yet been definitively demonstrated for CdTe. Here, we present a solution-based process, which achieves passivation and improved electrical performance when very small amounts of oxidized Al3+ species are deposited at the back surface of CdTe devices. The open circuit voltage (Voc) is increased and the fill factor (FF) and photoconversion efficiency (PCE) are optimized when the total amount added corresponds to ∼1 monolayer, suggesting that the passivation is surface specific. Addition of further Al3+ species, present in a sparse alumina-like layer, causes the FF and PCE to drop as the interface layer becomes blocking to current flow. The optimized deposit increases the average baseline PCE for both Cu-free devices and devices where Cu is present as a dopant. The greatest improvement is found when the Al3+ species are deposited prior to the CdCl2 activation step and Cu is employed. In this case, the best-cell efficiency was improved from 12.6 to 14.4%. Time-resolved photoluminescence measurements at the back surface and quantum efficiency measurements performed at the maximum power point indicate that the performance enhancement is due to a reduction in the interface recombination current at the back surface.Specific interactions between ligands and receptors on cell surface play an important role in the cell biological process. Nucleic acid aptamers as commonly used ligands enable specific recognition and tight binding to membrane protein receptors for modulation of cell fate. Therefore, molecular probes with aptamers can be applied for cancer diagnosis and targeted therapy by targeting overexpression membrane proteins of cancer cells. However, because of their fast degradation and rapid glomerulus clearance in vivo, the applications of aptamers in physiological conditions remain challenged. Inspired by natural multivalent interactions, many approaches have been developed to construct multivalent aptamers to improve the performance of aptamers in complex matrices with higher binding affinity, more stability, and longer circulation time. In this review, we first introduce the aptamer generation from purified protein-based SELEX and whole cell-based SELEX for targeting the cell surface. We then highlight the approaches to fabricate multivalent aptamers and discuss their properties. By integrating different materials (including inorganic nanomaterials, diacyllipid, polymeric nanoparticles, and DNA nanostructures) as scaffolds with an interface modification technique, we have summarized four kinds of multivalent aptamers. After that, representative applications in biosensing and targeted therapy are illustrated to show the elevated performance of multivalent aptamers. In addition, we analyze the challenges and opportunities for the clinical practices of multivalent aptamers.

The identification of asymptomatic patients at high risk of internal carotid artery (ICA) stenosis destabilization and symptom occurrence is crucial for prognosis estimation.

This study aimed to determine differences between patients with symptomatic and asymptomatic ICA stenosis and to develop a predictive model for the risk of symptomatic stenosis based on data collected in routine clinical practice.

The study included 163 patients with asymptomatic and 182 patients with symptomatic ICA stenosis greater than 70%. The study groups were compared in terms of stroke risk factors and comorbidities, coexisting ICA stenosis on the contralateral side, atherosclerosis in other arterial territories, and the morphology of atherosclerotic plaque assessed by transcervical ultrasound.

Independent risk factors for symptomatic ICA stenosis included male sex (odds ratio [OR], 2.94; 95% CI, 1.87-4.32; P <0.001), diabetes (OR, 2.86; 95% CI, 1.62-5.12; P <0.001), body mass index >25 kg/m2 (OR, 1.81; 95% CI, 1.72-1.86; P <0.001), chronic kidney disease (OR, 3.34; 95% CI, 1.34-8.87; P = 0.007), increased‑risk features of ultrasound plaque morphology (OR, 2.52; 95% CI, 1.29-3.72; P = 0.009), and coexisting atherosclerosis in 3 or 4 vascular areas (OR, 3.72; 95% CI, 1.77-7.23; P <0.001).The sensitivity and specificity of the scoring model designed to estimate the risk of symptomatic ICA stenosis reached 77.6% and 76.9%, respectively.

This cross‑sectional study indicated that the analysis of selected imaging and clinical parameters may enable clinicians to estimate the risk of symptomatic ICA stenosis. The proposed scoring system requires further prospective validation.

This cross‑sectional study indicated that the analysis of selected imaging and clinical parameters may enable clinicians to estimate the risk of symptomatic ICA stenosis. The proposed scoring system requires further prospective validation.