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Background Splenectomized patients are at an increased risk for overwhelming post-splenectomy infections typically with encapsulated bacteria. The clinical association between splenectomy and lymph-node tuberculosis is unclear. Case presentation We describe a rare case of disseminated tuberculous lymphadenitis in an 18-year-old woman with history of splenectomy because of hereditary sherocytosis. She was admitted with enlargement of bilateral-cervical and left-axillary lymph nodes and fever. A diagnosis of probable tuberculosis was made based on the findings of fine-needle aspiration. Histology showed granulomas and extensive caseous necrosis, with the site of puncture located at an enlarged lymph node on the right side. The diagnosis was confirmed via nucleic-acid amplification tests following excisional biopsy of the left axillary lymph node. Disseminated tuberculous lymphadenitis was localized in the bilateral neck, right lung hilum, left sub-axillary region, and mediastinum, as detected from contrast-enhanced computed tomography of the neck. Conclusions Mycobacterium tuberculosis infection should be considered in children and adolescents with extensive enlargement of lymph nodes after splenectomy.

Objective: Drug-resistant tuberculosis (DR-TB) in children seriously threatens TB control. Information on the epidemiology and characteristics of DR-TB in children in China is limited. We studied data in Shenyang Tenth People's Hospital to understand the DR-TB epidemiology in children in Shenyang. Design or Methods: We retrospectively analyzed drug resistance testing data of pediatric TB patients between 2017 and 2021, and included 2976 clinically-diagnosed pediatric TB patients. We described the epidemiology of DR-TB and analyzed the trends of DR-TB incidence. The Kappa value was calculated to assess the agreement between MGIT 960 DST and Xpert MTB/RIF for detecting rifampicin resistance. Multivariate logistic regression was used to identify the risk factors for DR-TB in pediatric patients. Results: Of the 2976 TB patients, 1076 were confirmed by MGIT 960 culture and/or Xpert MTB/RIF. Among the 806 patients identified by MGIT 960 culture, 232 cases (28.78%) were DR-TB. Resistance to the six drugs was in the following order: streptomycin (21.09%), isoniazid (9.35%), rifampin (15.01%), levofloxacin (6.20%), ethambutol (4.22%), and amikacin (3.23%). Alarmingly, 12.90% were MDR-TB (104/806), including 28 (3.47%) pre-XDR-TB. Of the 1076 pediatric TB patients, 295 (27.4%) developed DR-TB to any one drug (including 69 rifampicin-resistant cases identified by Xpert MTB/RIF only). No difference was found in the incidence of pediatric DR-TB between 2017 and 2021. Among 376 patients who were positive for both methods, using the MGIT 960 DST results as the gold standard, Xpert MTB/RIF's sensitivity for detecting rifampicin resistance was 91.38% and its specificity was 94.65%. Conclusion: Between 2017 and 2021, the DR-TB incidence in children remained unchanged in Shenyang. RR-TB, MDR-TB, and even Pre-XDR-TB require attention in children with drug-resistant TB. Xpert MTB/RIF helped to detect more rifampicin-resistant pediatric patients; thus Xpert MTB/RIF should be widely used as an important complementary tool to detect rifampicin-resistant TB in children. Keywords: tuberculosis, drug-resistant, children, rifampicin, Xpert MTB/RIF, drug susceptibility testing

Using TB-LAMP for diagnosing pediatric PTB, however, still requires systematic evaluation. Here, we evaluated TB-LAMP performance alone and in combination with conventional assays for diagnosing PTB in Chinese children, using mycobacterial culture or CCRS (the composite clinical reference standard) as references. BALF samples were collected at Shenyang Tenth People's Hospital from 251 children susceptible to TB infection with indications for fiberoptic bronchoscopy. When mycobacterial culture was the reference, TB-LAMP used alongside smear microscopy doubled sensitivity for detecting pediatric PTB compared with smear microscopy alone (82.5% vs 40.0%). When CCRS was the reference, AFB microscopy, MTB culture, and TB-LAMP had sensitivities of 16.5%, 30.1%, and 51.1%, respectively, and specificities of 98.2%, 100.0%, and 99.1%. Combining MTB culture with TB-LAMP gave a sensitivity of 61.1% and specificity of 96.6%. TB-LAMP identified 39.3% and 43.2% of cases with negative MTB culture or AFB microscopy results. TB-LAMP using BALF samples provided faster results, allowing early and accurate PTB diagnosis. Our findings provide insights for optimizing diagnostic algorithms for pediatric PTB.

We introduce a new paradigm for generating high-purity vortex beams with metasurfaces. By applying optical neural networks to a system of cascaded phase-only metasurfaces, we demonstrate the efficient generation of high-quality Laguerre-Gaussian (LG) vortex modes. Our approach is based on two metasurfaces where one metasurface redistributes the intensity profile of light in accord with Rayleigh-Sommerfeld diffraction rules, and then the second metasurface matches the required phases for the vortex beams. Consequently, we generate high-purity LG p,l optical modes with record-high Laguerre polynomial orders p  = 10 and l  = 200, and with the purity in p , l and relative conversion efficiency as 96.71%, 85.47%, and 70.48%, respectively. Our engineered cascaded metasurfaces suppress greatly the backward reflection with a ratio exceeding −17 dB. Such higher-order optical vortices with multiple orthogonal states can revolutionize next-generation optical information processing. The authors demonstrate an efficient way to generate high-purity vortex beams by applying optical neural networks to cascaded phase-only metasurfaces. Specifically, they present record-high-quality Laguerre-Gaussian ( LG p,l ) optical modes with polynomial orders p  = 10 and l  = 200 with purity in p , l and relative conversion efficiency of 96%, 85%, and 70%, respectively.

Recent years have witnessed a rapid development in the field of structural coloration, colors generated from the interaction of nanostructures with light. Compared to conventional color generation based on pigments and dyes, structural color generation exhibits unique advantages in terms of spatial resolution, operational stability, environmental friendliness, and multiple functionality. Here, we discuss recent development in structural coloration based on layered thin films and optical metasurfaces. This review first presents fundamentals of color science and introduces a few popular color spaces used for color evaluation. Then, it elaborates on representative physical mechanisms for structural color generation, including Fabry–Pérot resonance, photonic crystal resonance, guided mode resonance, plasmon resonance, and Mie resonance. Optimization methods for efficient structure parameter searching, fabrication techniques for large-scale and low-cost manufacturing, as well as device designs for dynamic displaying are discussed subsequently. In the end, the review surveys diverse applications of structural colors in various areas such as printing, sensing, and advanced photovoltaics.

Augmented reality (AR) display, which superimposes virtual images on ambient scene, can visually blend the physical world and the digital world and thus opens a new vista for human–machine interaction. AR display is considered as one of the next-generation display technologies and has been drawing huge attention from both academia and industry. Current AR display systems operate based on a combination of various refractive, reflective, and diffractive optical elements, such as lenses, prisms, mirrors, and gratings. Constrained by the underlying physical mechanisms, these conventional elements only provide limited light-field modulation capability and suffer from issues such as bulky volume and considerable dispersion, resulting in large size, severe chromatic aberration, and narrow field of view of the composed AR display system. Recent years have witnessed the emerging of a new type of optical elements—metasurfaces, which are planar arrays of subwavelength electromagnetic structures that feature an ultracompact footprint and flexible light-field modulation capability, and are widely believed to be an enabling tool for overcoming the limitations faced by current AR displays. Here, we aim to provide a comprehensive review on the recent development of metasurface-enabled AR display technology. We first familiarize readers with the fundamentals of AR display, covering its basic working principle, existing conventional-optics-based solutions, as well as the associated pros and cons. We then introduce the concept of optical metasurfaces, emphasizing typical operating mechanisms, and representative phase modulation methods. We elaborate on three kinds of metasurface devices, namely, metalenses, metacouplers, and metaholograms, which have empowered different forms of AR displays. Their physical principles, device designs, and the performance improvement of the associated AR displays are explained in details. In the end, we discuss the existing challenges of metasurface optics for AR display applications and provide our perspective on future research endeavors.

Dielectric metasurfaces, composed of planar arrays of subwavelength dielectric structures that collectively mimic the operation of conventional bulk optical elements, have revolutionized the field of optics by their potential in constructing high-efficiency and multi-functional optoelectronic systems on chip. The performance of a dielectric metasurface is largely determined by its constituent material, which is highly desired to have a high refractive index, low optical loss and wide bandgap, and at the same time, be fabrication friendly. Here, we present a new material platform based on tantalum pentoxide (Ta2O5) for implementing high-performance dielectric metasurface optics over the ultraviolet and visible spectral region. This wide-bandgap dielectric, exhibiting a high refractive index exceeding 2.1 and negligible extinction coefficient across a broad spectrum, can be easily deposited over large areas with good quality using straightforward physical vapor deposition, and patterned into high-aspect-ratio subwavelength nanostructures through commonly-available fluorine-gas-based reactive ion etching. We implement a series of high-efficiency ultraviolet and visible metasurfaces with representative light-field modulation functionalities including polarization-independent high-numerical-aperture lensing, spin-selective hologram projection, and vivid structural color generation, and the devices exhibit operational efficiencies up to 80%. Our work overcomes limitations faced by scalability of commonly-employed metasurface dielectrics and their operation into the visible and ultraviolet spectral range, and provides a novel route towards realization of high-performance, robust and foundry-manufacturable metasurface optics.

Central nervous system parvalbumin-positive interneurons (PV-INs) are crucial and highly vulnerable to various stressors. They also play a significant role in the pathological processes of many neuropsychiatric diseases, especially those associated with cognitive impairment, such as Alzheimer’s disease (AD), vascular dementia (VD), Lewy body dementia, and schizophrenia. Although accumulating evidence suggests that the loss of PV-INs is associated with memory impairment in dementia, the precise molecular mechanisms remain elusive. In this review, we delve into the current evidence regarding the physiological properties of PV-INs and summarize the latest insights into how their loss contributes to cognitive decline in dementia, particularly focusing on AD and VD. Additionally, we discuss the influence of PV-INs on brain development, the variations in their characteristics across different types of dementia, and how their loss affects the etiology and progression of cognitive impairments. Ultimately, our goal is to provide a comprehensive overview of PV-INs and to consider their potential as novel therapeutic targets in dementia treatment.

Structural colors, resulting from the interaction of light with nanostructured materials rather than pigments, present a promising avenue for diverse applications ranging from ink-free printing to optical anti-counterfeiting. Achieving structural colors with high purity and brightness over large areas and at low costs is beneficial for many practical applications, but still remains a challenge for current designs. Here, we introduce a novel approach to realizing large-scale structural colors in layered thin film structures that are characterized by both high brightness and purity. Unlike conventional designs relying on single Fabry–Pérot cavity resonance, our method leverages coupled resonance between adjacent cavities to achieve sharp and intense transmission peaks with significantly suppressed sideband intensity. We demonstrate this approach by designing and experimentally validating transmission-type red, green, and blue colors using an Ag/SiO /Ag/SiO /Ag configuration on fused silica substrate. The measured spectra exhibit narrow resonant linewidths (full width at half maximum ∼60 nm), high peak efficiencies (>40 %), and well-suppressed sideband intensities (∼0 %). In addition, the generated color can be easily tuned by adjusting the thickness of SiO layer, and the associated color gamut coverage shows a wider range than many existing standards. Moreover, the proposed design method is versatile and compatible with various choices of dielectric and metallic layers. For instance, we demonstrate the production of angle-robust structural colors by utilizing high-index Ta as the dielectric layer. Finally, we showcase a series of printed color images based on the proposed structures. The coupled-cavity-resonance architecture presented here successfully mitigates the trade-off between color brightness and purity in conventional layered thin film structures and provides a novel and cost-effective route towards the realization of large-scale and high-performance structural colors.

Background Vascular dementia, the second most common type of dementia globally after Alzheimer's disease, is associated with neuroinflammation. Activation of the NLRP3 inflammasome, an important pattern recognition receptor in human innate immunity, plays a key role in the pathogenesis of vascular dementia. Results The NLRP3 inflammasome pathway destroys neuronal cells primarily through the production of IL‐18 and IL‐1β. Moreover, it exacerbates vascular dementia by producing IL‐18, IL‐1β, and the N‐terminal fragment of GSDMD, which also contributes to neuronal cell death. Thus, blocking the NLRP3 inflammasome pathway presents a new therapeutic strategy for treating vascular dementia, thereby delaying or curing the disease more effectively and mitigating adverse effects. Conclusions This review explores the role and mechanisms of the NLRP3 inflammasome in vascular dementia, summarizing current research and therapeutic strategies. Investigating the activation of the NLRP3 inflammasome can reveal the pathogenesis of vascular dementia from a new perspective and propose innovative preventive and treatment strategies.