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SUMMARY Southeast China is one of the most important polymetallic metallogenic provinces in the world. However, distinct differences in the type and origin of the mineral deposits are present between the major metallogenic belts in this province. To deepen our knowledge of this regional metallogenic setting, investigate the factors controlling its metallogenic differences and explore the feasibility of active and passive seismic imaging, we performed a multibatch seismic experiment using active and passive sources with the help of 437 short-period seismographs deployed across the Qin-Hang and Wuyishan metallogenic belts in Southeast China. We resolved the S-wave velocity structure beneath the profile using ambient noise tomography and derived a Vp/Vs model by combining with a published P-wave model. A good correlation between the obtained seismic velocity models and geological observations is observed. The Proterozoic volcanic-sedimentary rock series and the Fuzhou-Yongfeng sedimentary basin are identified by low P- and S-wave velocities, high Vp/Vs ratios and low S-wave velocity perturbations. Within the core of the Wuyishan Metallogenic Belt, several narrow, elongated and low seismic velocity anomalies are considered to be signs of the nearby fault zones, and these anomalies provide reference information on the extension and pattern of these faults at depth. Combined with the geological and mineralogical evidence, we propose that theses faults function as ore-guiding structures and facilitate the formation of regionally representative mineral species and metal assemblages.

Thiolated/selenolated amino acids are irreplaceable despite their rare abundance in proteins. They play critical roles in regulating the conformation and function of proteins and peptide design as well as bioconjugation. Furthermore, β-thiolated/selenolated amino acids are important motifs in native chemical ligation-dechalcogenation strategy for protein synthesis. However, a universal method to access enantiopure β-thiolated/selenolated amino acids has not been reported. Herein, we developed a practical strategy for the preparation of a variety of enantiopure β-thiolated/selenolated amino acids via photoredox-catalyzed Giese reaction.

Controlling the morphology of silver nanoparticles on a cramped and curved optical fiber facet is urgently needed to obtain SERS optical fiber probes with high performance. In this work, a fast and simple method, PVP-assisted silver mirror reaction, is employed to synthesize SERS fiber probes. The morphology of silver on a cramped optical fiber facet can be controlled by optimizing the reaction conditions. The influences of reaction conditions, including the PVP/AgNO3 molar ratio, ammonium hydroxide concentration, silver nitrate concentration, type of the reducing saccharide and the pH value of Tollens’ solution, on the morphology and SERS performance of the fiber probes were investigated. The results show that silver nanoparticles can be densely distributed on the optical fiber facet with narrow interparticle gaps by varying these reaction parameters. The resultant SERS fiber probe shows high sensitivity and good reproducibility by using 4-aminothiophenol (4-ATP) as the probing molecule. Furthermore, the localized electromagnetic field of silver nanoparticles giving rise to enormous SERS signal amplification was simulated to clarify the SERS performance of the fiber probe. To the best of our knowledge, in situ detection of the analyte in a confined area and a curved channel using the SERS fiber probe is verified for the first time. The obtained SERS fiber probe shows promising applications in flexible detection for early diagnosis of major diseases and critical conditions including confined, remote and hazardous environments.

As indicators of diseases, blood biochemical values play a crucial role in clinical practice and assessments of animals’ health condition. The rising population of homing pigeons in China has prompted needs for reliable blood biochemical reference intervals. Therefore, the aim of this study was to establish biochemical reference intervals for homing pigeons. Heparinized whole blood samples obtained from 77 clinically healthy pigeons were analyzed by Zoetis Abaxis VetScan VS2 with VetScan Avian/Reptilian Profile Plus Rotor. Reference intervals for pigeons were computed by Excel with Reference Value Advisor V2.1. The statistical analysis performed by SPSS program revealed correlations between biochemical analytes. Effects of sex and age and validity of published reference intervals were also discussed. The present results serve as a useful guide to broaden the scope of pigeon breeding industry.

Geological studies show that the southern part of Ailaoshan-Red River shear zone (ALSRRSZ) has experienced complex metallogenic processes and multi-stage non-uniform uplifting, called oblique uplifting since the Cenozoic. To detect the deep structure and geodynamic background beneath Daping, Chang’an and other gold and polymetallic deposits in this area, we carried out a high-density short-period seismic array survey in southern Yunnan province. The array used is approximately 240 km long with an interval of 500 m between two adjacent stations. Based on the data collected by the array, we used H-κ stacking and common conversion point (CCP) methods of receiver functions to reveal the fine crustal structure beneath this array, which was located from Lvchun (western end) to the east and ended in Maguan. The three main conclusions are as follows. (1) The average crustal thickness is approximately 37 km and the Vp/Vs ratio is 1.75. However, the thickness and Vp/Vs ratio of the Ailao Mountain are rather greater or higher than those of the western Lanping-Simao Basin and eastern South-China block. These results may indicate that the crust is rich in ferromagnesian minerals or has a thermal fluid anomaly after orogenic movement. (2) There are two obvious inclined interfaces beneath the Ailao Mountain in the mid-upper crust, which suggests that strong deformation occurred there during the orogenic period. Some evidences, such as the weak converted-wave Pms phase from the Moho, low P-wave velocities of the upper mantle, high surface heat flow values, and generally developed hot springs, indicate that a strong crust-mantle interaction exists in the southern segments of the Ailaoshan-Red River shear zone. These interactions include a diapir of mantle-sourced magma (stronger in the east than that in the west), lateral collision from the Indian Plate, and the differential uplift caused by the strike-slip movement of the Red River Fault. All of above deep processes led to the Cenozoic oblique uplifting of Ailao Mountain. (3) By combining the location of the deposits on the surface, characteristics of the average crustal Vp/Vs ratio, hypocenters of the small earthquakes along the research profile, Moho shape, and horizontal variations of the Pms phase amplitudes, we speculate that the Ailaoshan Fault was the upgoing conduit for metallogenic magma and played a significant role in the Cenozoic development of the multiform metal deposits around the Ailao Mountain area.

Recently, the Fano effect of aluminum nanostructures has attracted a lot of attentions in several detector and sensor applications, but the role of coupling gap in it remains unintuitive. In this paper, a homotactic aluminum rod trimer (HART) is designed to form the plasmonic Fano resonances and visualize the important role of coupling gap size. The plasmon hybridization model and far field images were used to qualitatively describe the formation mechanism of Fano resonance. The simulation results intuitively show that the Fano dip of HART with a smaller coupling gap size has a higher red-shift speed when increasing the refractive index of surrounding environment or the length of HART with a fixed axial ratio (LS/LL = 0.6). Our study provides the insights to the key role of coupling gap in the performance of Fano structures.

Introduction: Pleural empyema is a common disease and involves an increasing number of patients. Here, we describe a case of pleural empyema and bacteremia secondary to hemorrhage of arteriovenous malformation (AVM) in the oral and maxillofacial regions. Case Summary: A 23-year-old female diagnosed with maxillofacial AVM previously presented to our hospital with fever and dyspnea for 8 days. Chest computed tomography (CT) images showed that she had pleural empyema. Bacterial detection showed the growth of Pseudomonas aeruginosa, Actinomyces odontolyticus, and Parvimonas micra. Antibiotic therapy combined with pleural space drainage were not effective until the hemorrhage of the AVM stopped. Conclusion: AVM rupture and bleeding may lead to persistent or refractory infection, and hemostasis is vital in preventing infection secondary to AVM.

Ginsenoside Rg3 is one of the main constituents of Panax ginseng. Compelling evidence has demonstrated that ginsenoside Rg3 is capable of inhibiting inflammation. However, the mechanism mediating its anti-inflammatory effects remain unclear. Here we show that ginsenoside Rg3 blocks IL-1β secretion and caspase-1 activation through inhibiting LPS priming and the NLRP3 inflammasome activation in human and mouse macrophages. Rg3 specifically inhibits activation of NLRP3 but not the NLRC4 or AIM2 inflammasomes. In addition, Rg3 has no effect on upstream regulation of NLRP3 inflammasome, such as K+ efflux, ROS production, or mitochondrial membrane potential. Mechanistically, Rg3 abrogates NEK7-NLRP3 interaction, and subsequently inhibits NLRP3-ASC interaction, ASC oligomerization, and speckle formation. More importantly, Rg3 can reduce IL-1β secretion induced by LPS in mice and protect mice from lethal endotoxic shock. Thus, our findings reveal an anti-inflammatory mechanism for Rg3 and suggest its potential use in NLRP3-driven diseases.

The demand for ever-smaller devices increases with the development of the semiconductor industry. High-resolution patterning based on lithography is significant to fabricate ultra-small nanostructures in various nanodevices. With the minimization of feature size down to nanometric scale, it is challenging to reliably define ultra-small features and structures through lithographic approaches. The ultra-small resist structures defined by lithography approaches usually suffer from mechanical instability behaviors during the development and drying process. The stable mechanical behaviors of lithography-defined resist nanopatterns are the important issue for reliable fabrication. Exploring the mechanical stability of resist patterns is of great importance both scientifically and technologically. Hydrogen silsesquioxane (HSQ) is a high-resolution negative-tone electron-beam resist for sub-10-nm fabrication. But, the ultra-small electron-beam exposed HSQ resist structures usually suffer from collapse and displacement after the development process. Hence, it is essential to understand the stability behavior of HSQ resist nanostructures to reliably fabricate various nanodevices. But, a systematic study of the stability behavior of HSQ is still lacking. To address this issue, we exposed the HSQ nanopillars on different substrates and dried them using different drying methods to probe the factors of critical dimensions, substrate adhesion, and dry methods for reliable HSQ nanopillars fabrication in this work. Through the analysis of experimental data, we found the adhesion dominates the mechanical stability of HSQ nanopillars at the ultra-small scale. By using finite element analysis, we systematically explored the role of the capillary effect in the two main unstable mechanics behaviors (collapse and displacement). To suppress the capillary forces, we optimized the drying process with the use of CO2 supercritical drying. We further provided an effective and facile method through spin-drying in the atmosphere to improve the stability of lithography-defined HSQ pillars.

A variety of β-thiolated aryl amino acids were readily synthesized in moderate to excellent yields via 1,4-addition from a readily-accessible thiazoline precursor, which can be prepared from cysteine methyl ester hydrochloride in just three steps. The thiolated products can be subsequently deprotected within one single step in high yields and used directly for subsequent solid-phase peptide synthesis.

Anaerobic digestion technology is widely used for treatment of swine and dairy manures in livestock farms, but the digested swine and dairy manures (SD-S, SD-D) must be properly disposed. In this study, hydrothermal carbonization (HTC) was used to deal with SD-S and SD-D. The resulting hydrochars (HC-S and HC-D) were investigated for the migration, speciation and potential environmental risk of metal(loid)s therein. The results showed that about 20%−50% of metal(loid)s in SD-S and 11%−36% in SD-D lost through the dissolution of the metal(loid)s in solution during HTC process. The remaining metal(loid)s were more concentrated in HC-D compared to HC-S. The concentrations of water-extractable metal(loid)s showed clear decrease trend in HC-S and HC-D. The bioavailable metal(loid) fraction (acid soluble/exchangeable fraction and reducible fraction) were transformed into the stable fraction (residual fraction) during HTC process. The results indicated that HTC process could immobilize most metal(loid)s leaching from HC-S and HC-D, except for Zn and Cd in HC-S. The maximum leaching concentrations of all metal(loid)s happened at pH of 2; meanwhile less fraction of metal(loid)s can be leached out from HC-D into water. The environmental risk assessment values suggested that HC-D was more environment-friendly than HC-S. This study provides a useful support for reuse of HC-S and HC-D as pollution remediation and soil amendment with very low leaching toxicity and potential ecological risk of metal(loid)s.

Interband-transition-induced absorption of gold films limits its color rendering in the blue part of the visible spectrum. In this work, we investigate extending the color of ultra-thin gold film to the blue region via Fabry-Perot-Cavity-Resonance-Enhanced reflection. Systematic experiments and simulations were conducted to demonstrate the color variation of the Fabry-Perot cavities. By choosing the appropriate dielectric thickness, colors covering the whole visible range including blue color were realized. The electronic field and absorbed power distribution were analyzed to understand the origin of the blue color. A multi-layer Fresnel reflection equation was employed to explain the whole color variation of this structure and the theoretical calculations were in agreement with both simulations and experimental results. Our work provides an approach to achieve blue color for gold and may have potential applications in surface decoration and functional optical elements.

Reliable fabrication of gold nanoparticles with desirable size, geometry and spatial arrangement is essential for plasmonic applications. A common fabrication flow usually involves electron-beam lithography and a vacuum-evaporation-based lift-off process or etching. In this work, we evaluate an alternative approach to directly fabricate a plasmonic gold nanoparticle array without involving the vacuum evaporation process by using a chloroauric acid/poly(vinyl pyrrolidone) (HAuCl4/PVP) hybrid as a functional electron-beam resist. Systematic experiments were conducted to investigate the patterning behaviors in the fabrication process. With the optimized fabrication parameters, we show that the HAuCl4/PVP composite resist has a high patterning resolution and pure gold nanoparticles with tens of nanometers can be obtained after an annealing-based pyrolysis process. More particularly, compared to the patterned plasmonic gold nanoparticles obtained by conventional methods, the gold nanoparticles fabricated by our method can be transferred to soft substrates due to the absence of an adhesion layer, enabling various potential applications in flexible and stretchable optics. As an example, we demonstrated that the transferred gold nanoparticle array can be conformably assembled onto a flat gold surface to form a particle-on-film structure for surface-enhanced Raman scattering (SERS) applications.

We proposed an incoherent self-interference digital holography imaging system based on the Michelson interferometer. The proposed system records holograms of USAF1951 resolution target, herbaceous stem crosscut, and osteocyte. The reconstruction of the captured hologram using a three-step generalized phase shift can effectively eliminate bias and a twin image and obtain a clear reconstructed image. Element 3 in group 9 on the USAF1951 resolution target can be clearly seen, and the resolution achieves 645 lp / mm. Results indicate that the diffraction distance can influence the reconstructed image quality, which was confirmed by analyzing their relationship. In addition, the hair hologram was reconstructed, thereby demonstrating that the proposed system can record a 3D image of the object.

Surface plasmons in metals promise many fascinating properties and applications in optics, sensing, photonics and nonlinear fields. Plasmonic nanostructures with extremely small features especially demonstrate amazing new effects as the feature sizes scale down to the sub-nanometer scale, such as quantum size effects, quantum tunneling, spill-out of electrons and nonlocal states etc. The unusual physical, optical and photo-electronic properties observed in metallic structures with extreme feature sizes enable their unique applications in electromagnetic field focusing, spectra enhancing, imaging, quantum photonics, etc. In this review, we focus on the new effects, fabrication and applications of plasmonic metal nanostructures with extremely small features. For simplicity and consistency, we will focus our topic on the plasmonic metal nanostructures with feature sizes of sub-nanometers. Subsequently, we discussed four main and typical plasmonic metal nanostructures with extremely small features, including: (1) ultra-sharp plasmonic metal nanotips; (2) ultra-thin plasmonic metal films; (3) ultra-small plasmonic metal particles and (4) ultra-small plasmonic metal nanogaps. Additionally, the corresponding fascinating new effects (quantum nonlinear, non-locality, quantum size effect and quantum tunneling), applications (spectral enhancement, high-order harmonic wave generation, sensing and terahertz wave detection) and reliable fabrication methods will also be discussed. We end the discussion with a brief summary and outlook of the main challenges and possible breakthroughs in the field. We hope our discussion can inspire the broader design, fabrication and application of plasmonic metal nanostructures with extremely small feature sizes in the future.

Ultrasmall metallic nanogaps are of great significance for wide applications in various nanodevices. However, it is challenging to fabricate ultrasmall metallic nanogaps by using common lithographic methods due to the limited resolution. In this work, we establish an effective approach for successful formation of ultrasmall metallic nanogaps based on the spontaneous nanoscale dewetting effect during metal deposition. By varying the initial opening size of the exposed resist template, the influence of dewetting behavior could be adjusted and tiny metallic nanogaps can be obtained. We demonstrate that this method is effective to fabricate diverse sub-10 nm gaps in silver nanostructures. Based on this fabrication concept, even sub-5 nm metallic gaps were obtained. SERS measurements were performed to show the molecular detection capability of the fabricated Ag nanogaps. This approach is a promising candidate for sub-10 nm metallic gaps fabrication, thus possessing potential applications in nanoelectronics, nanoplasmonics, and nano-optoelectronics.

Background Feline calicivirus (FCV) is a common pathogen of felids, and FCV vaccination is regularly practiced. The genetic variability and antigenic diversity of FCV hinder the effective control and prevention of infection by vaccination. Improved knowledge of the epidemiological characteristics of FCV should assist in the development of more effective vaccines. Objectives This study aims to determine the prevalence of FCV in a population of cats with FCV-suspected clinical signs in Hangzhou and to demonstrate the antigenic and genetic relationships between vaccine status and representative isolated FCV strains. Methods Cats (n = 516) from Hangzhou were investigated between 2018 and 2020. The association between risk factors and FCV infection was assessed. Phylogenetic analyses based on a capsid coding sequence were performed to identify the genetic relationships between strains. In vitro virus neutralization tests were used to assess antibody levels against isolated FCV strains in client-owned cats. Results The FCV-positive rate of the examined cats was 43.0%. Risk factors significantly associated with FCV infection were vaccination status and oral symptoms. Phylogenetic analysis revealed a radial phylogeny with no evidence of temporal or countrywide clusters. There was a significant difference in the distribution of serum antibody titers between vaccinated and unvaccinated cats. Conclusions This study revealed a high prevalence and genetic diversity of FCV in Hangzhou. The results indicate that the efficacy of FCV vaccination is unsatisfactory. More comprehensive and refined vaccination protocols are an urgent and unmet need.

The field confinement of plasmonic systems enables spectral tunability under structural variations or environmental perturbations, which is the principle for various applications including nanorulers, sensors, and color displays. Here, we propose and demonstrate that materials with anomalous dispersion, such as Ge in the visible, improve spectral tunability. We introduce our proposal with a semianalytical guided mode picture. Using Ge-based film (Ag/Au)-coupled gap plasmon resonators, we implement two architectures and demonstrate the improved tunability with single-particle dark-field scattering, ensemble reflection, and color generation. We observe three-fold enhancement of tunability with Ge nanodisks compared with that of Si, a normal-dispersion material in the visible. The structural color generation of large array systems, made of inversely fabricated Ge-Ag resonators, exhibits a wide gamut. Our results introduce anomalous material dispersion as an extra degree of freedom to engineer the spectral tunability of plasmonic systems, especially relevant for actively tunable plasmonics and metasurfaces.

Sulfur and selenium occupy a distinguished position in biology owing to their redox activities, high nucleophilicity, and acyl transfer capabilities. Thiolated/selenolated amino acids, including cysteine, selenocysteine, and their derivatives, play critical roles in regulating the conformation and function of proteins and serve as an important motif for peptide design and bioconjugation. Unfortunately, a general and concise method to attain enantiopure β-thiolated/selenolated amino acids remains an unsolved problem. Herein, we present a photoredox-catalyzed asymmetric method for the preparation of enantiopure β-thiolated/selenolated amino acids using a simple chiral auxiliary, which controls the diastereoselectivity of the key alkylation step and acts as an orthogonal protecting group in the subsequent peptide synthesis. Our protocol can be used to prepare a wide range of β-thiolated/selenolated amino acids on a gram scale, which would otherwise be difficult to obtain using conventional methods. The effect of our chemistry was further highlighted and validated through the preparation of a series of peptidyl thiol/selenol analogues, including cytochrome c oxidase subunit protein 7C and oxytocin.

INF39 is a nontoxic, irreversible, acrylate-based NLRP3 inhibitor and a further optimization of ethyl 2-((2-chlorophenyl) hydroxyl) methyl) acrylate (INF4E). However, the detail mechanism and the direct target of its anti-inflammatory activity is not clear. Here, we show that INF39 is a specific inhibitor for NLRP3 inflammasome activation. INF39 specifically suppresses NLRP3 activation but not the NLRC4 or AIM2 inflammasomes. INF39 has no effect on K+ efflux, ROS generation or mitochondrial membrane potential, which are the upstream events of NLRP3 inflammasome activation. In addition, INF39 has no direct inhibitory effect on GSDMD, which is the downstream event of inflammasomes. More importantly, INF39 inhibits the interaction of NEK7-NLRP3, and subsequently inhibits interaction of NLRP3-NLRP3, NLRP3-ASC, ASC oligomerization and speckle formation. Altogether, our study unveils a deeper anti-inflammatory mechanism for INF39 and suggests it could serve as a lead for developing novel therapeutics combating NLRP3-driven diseases.

Sub-wavelength aperture arrays featuring small gaps have an extraordinary significance in enhancing the interactions of terahertz (THz) waves with matters. But it is difficult to obtain large light-substance interaction enhancement and high optical response signal detection capabilities at the same time. Here, we propose a simple terahertz bow-tie aperture arrays structure with a large electric field enhancement factor and high transmittance at the same time. The field enhancement factor can reach a high value of 1.9×104 and the transmission coefficient of around 0.8 (the corresponding normalized-to-area transmittance is about 14.3) at 0.04 µm feature gap simultaneously. The systematic simulation results show that the designed structure can enhance the intensity of electromagnetic hotspot by continuously reducing the feature gap size without affecting the intensity of the transmittance. We also visually displayed the significant advantages of extremely strong electromagnetic hot spots in local terahertz refractive index detection, which provides a potential platform and simple strategy for enhanced THz spectral detection.

We introduce the mesoscopic electromagnetic boundary conditions and establish an experimental procedure to measure the dispersive surface response functions, enabled by observations of pronounced nonclassical effects—spectral shifts >30% and the breakdown of Kreibig-like broadening.

Reliable fabrication of multiscale metallic patterns with precise geometry and size at both the nanoscale and macroscale is of importance for various applications in electronic and optical devices. The existing fabrication processes, which usually involve film deposition in combination with electron-beam patterning, are either time-consuming or offer limited precision. Inspired by the kirigami, an ancient handicraft art of paper cutting, this work demonstrates an electron-beam patterning process for multiscale metallic structures with significantly enhanced efficiency and precision. Similar to the kirigami, in which the final pattern is defined by cutting its contour in a paper and then removing the unwanted parts, we define the target multiscale structures by first creating nanotrench contours in a metallic film via an electron-beam-based process and then selectively peeling the separated film outside the contours. Compared with the conventional approach, which requires the exposure of the whole pattern, much less exposure area is needed for nanotrench contours, thus enabling reduced exposure time and enhanced geometric precision due to the mitigated proximity effect. A theoretical model based on interface mechanics allows a clear understanding of the nanotrench-assisted selective debonding behaviour in the peeling process. By using this fabrication process, multiscale metallic structures with sub-10-nm up to submillimetre features can be reliably achieved, having potential applications for anti-counterfeiting and gap-plasmon-enhanced spectroscopy., Ancient art informs cutting-edge manufacturing method A centuries-old papercrafting technique has inspired an approach for the reproducible manufacture of metal structures with precisely defined macro- and nanoscale features. Many electronic devices incorporate such elements, but current production processes struggle with the ability to accurately sculpt both millimeter- and nanometer-sized design elements. Researchers led by Yihui Zhang of Tsinghua University and Huigao Duan of Hunan University tackled this challenge with a 21st century version of ‘kirigami’, an ancient aesthetic pursuit of artistic paper-cutting. The authors used an electron beam to precisely cut multiscale patterns into a thin metallic film, and then used adhesive tape to peel away unwanted elements of the film. Using this technique, the authors demonstrate the capability to produce a range of designs with both sub-millimeter and nanometer-scale features, which could prove useful in applications including anti-counterfeiting or optical detection.

INTRODUCTION: Changes in glucose levels may represent a powerful metabolic indicator for dementia in African Americans with diabetes. It is unclear whether these changes also occur in Caucasians. METHODS: A secondary data analysis using electronic medical records from 5228 African Americans and Caucasians 65 years and older. Mixed effects models with repeated serum glucose measurements were used to compare changes in glucose levels between African Americans and Caucasian patients with and without incident dementia. RESULTS: African Americans and Caucasians with diabetes had significantly different changes in glucose levels by dementia status (p

Reliable fabrication of micro/nanostructures with sub-10 nm features is of great significance for advancing nanoscience and nanotechnology. While the capability of current complementary metal-oxide semiconductor (CMOS) chip manufacturing can produce structures on the sub-10 nm scale, many emerging applications, such as nano-optics, biosensing, and quantum devices, also require ultrasmall features down to single digital nanometers. In these emerging applications, CMOS-based manufacturing methods are currently not feasible or appropriate due to the considerations of usage cost, material compatibility, and exotic features. Therefore, several specific methods have been developed in the past decades for different applications. In this review, we attempt to give a systematic summary on sub-10 nm fabrication methods and their related applications. In the first and second parts, we give a brief introduction of the background of this research topic and explain why sub-10 nm fabrication is interesting from both scientific and technological perspectives. In the third part, we comprehensively summarize the fabrication methods and classify them into three main approaches, including lithographic, mechanics-enabled, and post-trimming processes. The fourth part discusses the applications of these processes in quantum devices, nano-optics, and high-performance sensing. Finally, a perspective is given to discuss the challenges and opportunities associated with this research topic.

Highly sensitive and low-cost surface-enhanced Raman scattering (SERS) substrates are essential for practical applications of SERS. In this work, we report an extremely simple but effective approach to achieve sensitive SERS detection of molecules (down to 10–10 M) by using a particle/molecule/film sandwich configuration. Compared to conventional SERS substrates which are preprepared to absorb analyte molecules for detection, the proposed sandwich configuration is achieved by postassembling a flexible transparent gel tape embedded with plasmonic nanoparticles onto an Au film decorated with to-be-detected analyte molecules. In such a configuration, the individual plasmonic gel tape and Au film have low or no SERS activity but the final assembled sandwich structure shows strong SERS signal due to the formation of numerous hot spots at the particle–film interface, where the analyte molecules themselves serve as both spacer and signal probes. Because of its simple configuration, we demonstrate that the propos...

This paper presents a statistical method for analyzing the association between longitudinal cholesterol measurements and the timing of onset of dementia. The proposed approach jointly models the longitudinal and survival processes for each individual on the basis of a shared random effect, where a linear mixed effects model is assumed for the longitudinal component and an extended Cox regression model is employed for the survival component. A dynamic prediction model is built based on the joint model, which provides prediction of the conditional survival probabilities at different time points using available longitudinal measurements as well as baseline characteristics. We apply our method to the Indianapolis-Ibadan Dementia project, a 20-year study of dementia in elderly African Americans living in Indianapolis, Indiana. We find that with baseline covariates and comorbidities adjusted, the risk of dementia decreases by 1% per one mg/dl increase in total cholesterol. Therefore we conclude that, in...

Bioactive glass ceramics have excellent biocompatibility and osteoconductivity; and can form direct chemical bonds with human bones; thus, these ceramic are considered as “Smart” materials. In this study, we develop a new type of bioactive glass ceramic (AP40mod) as a scaffold containing Endothelial progenitor cells (EPCs) and Mesenchymal stem cells (BMSCs) to repair critical-sized bone defects in rabbit mandibles. For in vitro experiments: AP40mod was prepared by Dgital light processing (DLP) system and the optimal ratio of EPCs/BMSCs was screened by analyzing cell proliferation and ALP activity, as well as the influence of genes related to osteogenesis and angiogenesis by direct inoculation into scaffolds. The scaffold showed suitable mechanical properties, with a Bending strength 52.7 MPa and a good biological activity. Additionally, when EPCs/BMSCs ratio were combined at a ratio of 2:1 with AP40mod, the ALP activity, osteogenesis and angiogenesis were significantly increased. For in vivo experiments: application of AP40mod/EPCs/BMSCs (after 7 days of in vitro spin culture) to repair and reconstruct critical-sized mandible defect in rabbit showed that all scaffolds were successfully accurately implanted into the defect area. As revealed by macroscopically and CT at the end of 9 months, defects in the AP40mod/EPCs/BMSCs group were nearly completely covered by normal bone and the degradation rate was 29.9% compared to 20.1% in the AP40mod group by the 3D reconstruction. As revealed by HE and Masson staining analyses, newly formed blood vessels, bone marrow and collagen maturity were significantly increased in the AP40mod/EPCs/BMSCs group compared to those in the AP40mod group. We directly inoculated cells on the novel material to screen for the best inoculation ratio. It is concluded that the AP40mod combination of EPCs/BMSCs is a promising approach for repairing and reconstructing large load bearing bone defect.

Local, bulk response functions, e.g permittivity, and the macroscopic Maxwell equations completely specify the classical electromagnetic problem, which features only wavelength $\lambda$ and geometric scales. The above neglect of intrinsic electronic length scales $L_{\text{e}}$ leads to an eventual breakdown in the nanoscopic limit. Here, we present a general theoretical and experimental framework for treating nanoscale electromagnetic phenomena. The framework features surface-response functions---known as the Feibelman $d$-parameters---which reintroduce the missing electronic length scales. As a part of our framework, we establish an experimental procedure to measure these complex, dispersive surface response functions, enabled by quasi-normal-mode perturbation theory and observations of pronounced nonclassical effects---spectral shifts in excess of 30% and the breakdown of Kreibig-like broadening---in a quintessential multiscale architecture: film-coupled nanoresonators, with feature-sizes comparable to both $L_{\text{e}}$ and $\lambda$., Comment: 7 pages, 4 figures, supplementary included as ancillary file

The southern part of the Ailaoshan-Red River shear zone (ARRSZ) in southern Yunnan, is an important gold-bearing polymetallic metallogenic belt of China. To better understand the metallogenic tectonic setting and the magmatic activity in the area, we deployed a 240-km-long quasi-linear seismic array with numerous short-period stations spaced about 500 m across the ARRSZ. The shear-velocity structure of the upper crust along the survey profile is determined by ambient noise tomography using continuously recorded waveform data. The results show: (1) An upper crust characterized by a laterally varying S-velocity pattern and two high velocity bodies: one located mainly below the Ailaoshan metallogenic belt and the other further east below the Pingbian area, which are separated by a low velocity zone beneath the Red River Fault. (2) The upper crust model provides valuable information on Cenozoic magmatism. The high-velocity body below the Ailaoshan metallogenic zone likely corresponds to buried granitoid intrusions caused by early-stage Cenozoic magmatism, which might have been altered and mineralized. The high-velocity body near Pingbian could be the trace of basalt-generating late-stage Cenozoic magmatism, which is most likely the intrusive phase of the younger basalts. (3) Major regional faults are identified as ascending channels and/or emplacement/precipitation sites for magma and mineralized fluids, meaning that such faults play an ore-controlling function within the magmatic fluid ore-formation system.

Introduction High blood glucose levels may be responsible for the increased risk for dementia in diabetic patients. Methods A secondary data analysis merging electronic medical records (EMRs) with data collected from the Indianapolis–Ibadan Dementia project (IIDP). Of the enrolled 4105 African Americans, 3778 were identified in the EMR. Study endpoints were dementia, mild cognitive impairment (MCI), or normal cognition. Repeated serum glucose measurements were used as the outcome variables. Results Diabetic participants who developed incident dementia had a significant decrease in serum glucose levels in the years preceding the diagnosis compared to the participants with normal cognition ( P = .0002). They also had significantly higher glucose levels up to 9 years before the dementia diagnosis ( P = .0367). Discussion High glucose levels followed by a decline occurring years before diagnosis in African American participants with diabetes may represent a powerful presymptomatic metabolic indicator of dementia.

With their unique optical properties and distinct Raman signatures, graphitic nanomaterials can serve as substrates for surface-enhanced Raman spectroscopy (SERS) or provide signal amplification for bioanalysis and detection. However, a relatively weak Raman signal has limited further biomedical applications. This has been addressed by encapsulating gold nanorods (AuNRs) in a thin graphitic shell to form gold graphitic nanocapsules. This step improves plasmon resonance, which enhances Raman intensity, and has the potential for integrating two-photon luminescence (TPL) imaging capability. However, changing the morphology of gold graphitic nanocapsules such that high quality and stability are achieved remains a challenge. To address this task, we herein report a confinement chemical vapor deposition (CVD) method to prepare the construction of AuNR-encapsulated graphitic nanocapsules with these properties. Specifically, through morphological modulation, we (1) achieved higher plasmon resonance with near-IR incident light, thus achieving greater Raman intensity, and (2) successfully integrated two-photon luminescence dual-modal (Raman/TPL) bioimaging capabilities. Cancer-cell-specific aptamers were further modified on the AuNR@G graphitic surface through simple, but strong, π-π interactions to achieve imaging selectivity through differential cancer cell recognition.

The use of an intervening adhesion layer is essential in reliable fabrication of noble metallic nanostructures for optical and electronic devices. However, many emerging applications such as plasmonics and transfer printing raise the demand of metallic structures without adhesion layers, either to mitigate the plasmon damping or to facilitate the transfer processes. In this work, we systematically investigate the fabrication reliability of adhesion-free lithographic gold nanostructures on Si wafers and gold-coated substrates using a wet lift-off process. According to a large amount of statistical results, we comprehensively evaluate the patterning behavior of metallic nanostructures without adhesion promotion. Analytical modelling and control experiments are carried out to characterize the mechanics of their failure behaviors as a function of morphology and surface property. Our work provides useful information to the nanofabrication community to obtain adhesion-free gold nanostructures for plasmonic and transfer printing applications.

Reliable fabrication of metallic patterns at nanoscale is of great interest for various practical applications in nanodevices. Electron-beam-lithography based lift-off is the most often used method to define exquisite metal nanostructures at the 10-nm scale. In a common wet lift-off process, the metal material on top is lifted-off and washed away together with the sacrificial resist layer below. However, the wet lift-off process is sometimes ultrasonic agitation and/or heating-dependent and limited by the probable remained debris problem. In this work, we present an alternative lift-off process to obtain metallic patterns via removing the unwanted parts by using ion beam etching. We demonstrated that this ion-beam-etching based lift-off process is effective for isolated exposed negative-tone resist to fabricate nanoholes and nanoslits array and for dense networked exposed resist to fabricate high-density packed nanostructures. SERS measurements were conducted to demonstrate the molecular detection capability of the nanostructures with tiny gaps fabricated by this ion-beam-etching based lift-off process.

Visible-light color filters using patterned nanostructures have attracted much interest due to their various advantages such as compactness, enhanced stability, and environmental friendliness compared with traditional pigment or dye-based optical filters. While most existing studies are based on planar nanostructures with lateral variation in size, shape, and arrangement, the vertical dimension of structures is a long-ignored degree of freedom for the structural colors. Herein, we demonstrate a synthetic platform for transmissive color filter array by coordinated manipulations between height-varying nanocavities and their lateral filling fractions. The thickness variation of those nanocavities has been fully deployed as an alternative degree of freedom, yielding vivid colors with wide gamut and excellent saturation. Experimental results show that the color-rendering capability of the pixelated nanocavities can be still retained as pixels are miniaturized to 500 nm. Crosstalk between closely spaced pixels of a Bayer color filter arrangement was calculated, showing minimal crosstalk for 1 µ m 2 square subpixels. Our work provides an approach to designing and fabricating ultracompact color filter arrays for various potential applications including stained-glass microprints, microspectrometers, and high-resolution image sensing systems.

Hydrothermal carbonization (HTC) is an efficient conversion process that treats solid digestates from anaerobic digestion plants and converts it into valuable solid products. In this study, digestates of swine manure (DS_M) and rice straw (DS_S) were HTC-treated at 190 °C with biomass-to-water ratios of 1:4 and 1:9. The hydrochars were characterized physically and chemically to elucidate their potential as a valuable resource. The hydrochars from the solid digestates were acidic, and the dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and Brunauer-Emmett-Teller surface area (SBET) were significantly (P < 0.05) higher compared with that of the feedstocks and pyrochars. Mesopores were dominant in the hydrochars, where the pores had slit-type holes and a stratified structure. The hydrochars possessed more O functional groups and aromatic C=C and C-H band than the feedstocks and pyrochars. The hydrochars derived from solid digestates were better as a solid fuel because of their combustion property. The increase in the crystallinity of the hydrochars enhanced their stability. The hydrochars produced from the DS_M were more acidic than those from the DS_S. The HTCDS_S had a better adsorptive effect on pollutants than the HTCDS_M because of the higher SBET and optimal functional groups.

African Americans are especially at risk of hypertension and dementia. Antihypertensive medications reduce the risk of cardiovascular events, but may also reduce the risk of dementia. To assess the longitudinal effects of antihypertensive medications and blood pressure on the onset of incident dementia in a cohort of African Americans. Prospective cohort. 1236 community-dwelling patients from an inner-city public health care system, aged 65 years and older, with a history of hypertension but no history of dementia, and who had at least three primary care visits and a prescription filled for any medication. Blood pressure was the average of three seated measurements. Dementia was diagnosed using a two-stage design, with a screening evaluation every 2 to 3 years followed by a comprehensive in-home clinical evaluation for those with a positive screen. Laboratory, inpatient and outpatient encounter data, coded diagnoses and procedures, and medication records were derived from a health information exchange. Of the 1236 hypertensive participants without dementia at baseline, 114 (9%) developed incident dementia during follow-up. Individuals prescribed any antihypertensive medication (n = 816) were found to have a significantly reduced risk of dementia (HR = 0.57, 95% CI 0.37–0.88, p = 0.0114) compared to untreated hypertensive participants (n = 420). When this analysis was repeated including a variable indicating suboptimally treated blood pressure (> 140 mmHg systolic or >90 mmHg diastolic), the effect of antihypertensive medication was no longer statistically significant (HR = 0.65, 95% CI 0.32–1.30, p = 0.2217). Control of blood pressure in older adult African American patients with hypertension is a key intervention for preventing dementia, with similar benefits from most of the commonly available antihypertensive medications.