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Interlayer electronic coupling in two-dimensional materials enables tunable and emergent properties by stacking engineering. However, it also results in significant evolution of electronic structures and attenuation of excitonic effects in two-dimensional semiconductors as exemplified by quickly degrading excitonic photoluminescence and optical nonlinearities in transition metal dichalcogenides when monolayers are stacked into van der Waals structures. Here we report a van der Waals crystal, niobium oxide dichloride (NbOCl2), featuring vanishing interlayer electronic coupling and monolayer-like excitonic behaviour in the bulk form, along with a scalable second-harmonic generation intensity of up to three orders higher than that in monolayer WS2. Notably, the strong second-order nonlinearity enables correlated parametric photon pair generation, through a spontaneous parametric down-conversion (SPDC) process, in flakes as thin as about 46 nm. To our knowledge, this is the first SPDC source unambiguously demonstrated in two-dimensional layered materials, and the thinnest SPDC source ever reported. Our work opens an avenue towards developing van der Waals material-based ultracompact on-chip SPDC sources as well as high-performance photon modulators in both classical and quantum optical technologies1-4.
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Local adaptation is critical in speciation and evolution, yet comprehensive studies on proximate and ultimate causes of local adaptation are generally scarce. Here, we integrated field ecological experiments, genome sequencing, and genetic verification to demonstrate both driving forces and molecular mechanisms governing local adaptation of body coloration in a lizard from the Qinghai-Tibet Plateau. We found dark lizards from the cold meadow population had lower spectrum reflectance but higher melanin contents than light counterparts from the warm dune population. Additionally, the colorations of both dark and light lizards facilitated the camouflage and thermoregulation in their respective microhabitat simultaneously. More importantly, by genome resequencing analysis, we detected a novel mutation in Tyrp1 that underpinned this color adaptation. The allele frequencies at the site of SNP 459# in the gene of Tyrp1 are 22.22% G/C and 77.78% C/C in dark lizards and 100% G/G in light lizards. Model-predicted structure and catalytic activity showed that this mutation increased structure flexibility and catalytic activity in enzyme TYRP1, and thereby facilitated the generation of eumelanin in dark lizards. The function of the mutation in Tyrp1 was further verified by more melanin contents and darker coloration detected in the zebrafish injected with the genotype of Tyrp1 from dark lizards. Therefore, our study demonstrates that a novel mutation of a major melanin-generating gene underpins skin color variation co-selected by camouflage and thermoregulation in a lizard. The resulting strong selection may reinforce adaptive genetic divergence and enable the persistence of adjacent populations with distinct body coloration.
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Lagartos , Melaninas , Animales , Melaninas/genética , Lagartos/genética , Pez Cebra , Regulación de la Temperatura Corporal/genética , Pigmentación de la Piel/genética , ColorRESUMEN
Scalable and addressable integrated manipulation of qubits is crucial for practical quantum information applications. Different waveguides have been used to transport the optical and electrical driving pulses, which are usually required for qubit manipulation. However, the separated multifields may limit the compactness and efficiency of manipulation and introduce unwanted perturbation. Here, we develop a tapered fiber-nanowire-electrode hybrid structure to realize integrated optical and microwave manipulation of solid-state spins at nanoscale. Visible light and microwave driving pulses are simultaneously transported and concentrated along an Ag nanowire. Studied with spin defects in diamond, the results show that the different driving fields are aligned with high accuracy. The spatially selective spin manipulation is realized. And the frequency-scanning optically detected magnetic resonance (ODMR) of spin qubits is measured, illustrating the potential for portable quantum sensing. Our work provides a new scheme for developing compact, miniaturized quantum sensors and quantum information processing devices.
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BACKGROUND AND AIMS: The aim of this study was to determine if utilization of artificial intelligence (AI) in the course of endoscopic procedures can significantly diminish both the adenoma miss rate (AMR) and the polyp miss rate (PMR) compared with standard endoscopy. METHODS: We performed an extensive search of various databases, encompassing PubMed, Embase, Cochrane Library, Web of Science, and Scopus, until June 2023. The search terms used were artificial intelligence, machine learning, deep learning, transfer machine learning, computer-assisted diagnosis, convolutional neural networks, gastrointestinal (GI) endoscopy, endoscopic image analysis, polyp, adenoma, and neoplasms. The main study aim was to explore the impact of AI on the AMR, PMR, and sessile serrated lesion miss rate. RESULTS: A total of 7 randomized controlled trials were included in this meta-analysis. Pooled AMR was markedly lower in the AI group versus the non-AI group (pooled relative risk [RR], .46; 95% confidence interval [CI], .36-.59; P < .001). PMR was also reduced in the AI group in contrast with the non-AI control (pooled RR, .43; 95% CI, .27-.69; P < .001). The results showed that AI decreased the miss rate of sessile serrated lesions (pooled RR, .43; 95% CI, .20 to .92; P < .05) and diminutive adenomas (pooled RR, .49; 95% CI, .26-.93) during endoscopy, but no significant effect was observed for advanced adenomas (pooled RR, .48; 95% CI, .17-1.37; P = .17). The average number of polyps (Hedges' g = -.486; 95% CI, -.697 to -.274; P = .000) and adenomas (Hedges' g = -.312; 95% CI, -.551 to -.074; P = .01) detected during the second procedure also favored AI. However, AI implementation did not lead to a prolonged withdrawal time (P > .05). CONCLUSIONS: This meta-analysis suggests that AI technology leads to significant reduction of miss rates for GI adenomas, polyps, and sessile serrated lesions during endoscopic surveillance. These results underscore the potential of AI to improve the accuracy and efficiency of GI endoscopic procedures.
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BACKGROUND Ankylosing spondylitis (AS), a chronic inflammatory disease predominantly causing back pain, affects up to 0.5% of the global population, more commonly in males. Frequently undiagnosed in early stages, AS is often associated with comorbid depression and anxiety, imposing significant healthcare burdens. Despite available pharmaceutical treatments, exercise therapy (ET) has emerged as an effective, side-effect-free alternative, particularly for managing AS-induced back pain. This study aims to explore the research trends in ET for treating AS back pain from 2004-2023. MATERIAL AND METHODS A comprehensive analysis of 437 articles, sourced from the Science Citation Index-Expanded within the Web of Science Core Collection, was conducted using CiteSpace 6.2.R5. This study spanned from 2004 to October 15, 2023, examining publications, authors, institutions, and keywords to assess keyword co-occurrences, temporal progressions, and citation bursts. RESULTS Research interest in ET for AS began escalating around 2008 and has since shown steady growth. The USA emerged as a significant contributor, with Van der Heijde, Desiree, and RUDWALEIT M being notable authors. Key institutions include Assistance Publique Hopitaux Paris and UDICE-French Research Universities, with ANN RHEUM DIS being the most influential journal. The field's evolution is marked by interdisciplinary integration and branching into various sub-disciplines. CONCLUSIONS Exercise therapy for AS-induced back pain is a growing research area, necessitating further exploration in clinical management and rehabilitation strategies. The relationship between ET and osteoimmunological mechanisms remains a focal point for future research, with a trend towards personalized and interdisciplinary treatment approaches.
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Espondilitis Anquilosante , Masculino , Humanos , Espondilitis Anquilosante/terapia , Terapia por Ejercicio , Ejercicio Físico , Dolor de Espalda/terapia , BibliometríaRESUMEN
Infertility is a global health problem affecting millions of people of reproductive age worldwide, with approximately half caused by males. Chitosan oligosaccharide (COS) has strong antioxidant capacity, but its impact on the male reproductive system has not been effectively evaluated. To address this, we integrated RNA-seq, serum metabolomics and intestinal 16â¯S rDNA analysis to conduct a comprehensive investigation on the male reproductive system. The results showed that COS has potential targets for the treatment of oligospermia, which can promote the expression of meiotic proteins DDX4, DAZL and SYCP1, benefit germ cell proliferation and testicular development, enhance antioxidant capacity, and increase the expression of testicular steroid proteins STAR and CYP11A1. At the same time, COS can activate PI3K-Akt signaling pathway in testis and TM3 cells. Microbiome and metabolomics analysis suggested that COS alters gut microbial community composition and cooperates with serum metabolites to regulate spermatogenesis. Therefore, COS promotes male reproduction by regulating intestinal microorganisms and serum metabolism, activating PI3K-Akt signaling pathway, improving testicular antioxidant capacity and steroid regulation.
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On-chip light sources are an essential component of scalable photonic integrated circuits (PICs), and coupling between light sources and waveguides has attracted a great deal of attention. Photonic waveguides based on bound states in the continuum (BICs) allow optical confinement in a low-refractive-index waveguide on a high-refractive-index substrate and thus can be employed for constructing PICs. In this work, we experimentally demonstrated that the photoluminescence (PL) from a monolayer of tungsten sulfide (WS2) could be coupled into a BIC waveguide on a lithium-niobate-on-insulator (LNOI) substrate. Using finite-difference time-domain simulations, we numerically obtained a coupling efficiency of â¼2.3% for an in-plane-oriented dipole and a near-zero loss at a wavelength of 620 nm. By breaking through the limits of 2D-material integration with conventional photonic architectures, our work offers a new perspective for light-matter coupling in monolithic PICs.
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BACKGROUND: Cattle (Bos taurus) are a major large livestock, however, compared with other species, the transcriptional specificity of bovine oocyte development has not been emphasised. RESULTS: To reveal the unique transcriptional signatures of bovine oocyte development, we used integrated multispecies comparative analysis and weighted gene co-expression network analysis (WGCNA) to perform bioinformatic analysis of the germinal follicle (GV) and second meiosis (MII) gene expression profile from cattle, sheep, pigs and mice. We found that the expression levels of most genes were down-regulated from GV to MII in all species. Next, the multispecies comparative analysis showed more genes involved in the regulation of cAMP signalling during bovine oocyte development. Moreover, the green module identified by WGCNA was closely related to bovine oocyte development. Finally, integrated multispecies comparative analysis and WGCNA picked up 61 bovine-specific signature genes that participate in metabolic regulation and steroid hormone biosynthesis. CONCLUSION: In a short, this study provides new insights into the regulation of cattle oocyte development from a cross-species comparison.
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Oocitos , Transcriptoma , Bovinos , Animales , Ratones , Ovinos/genética , Porcinos , Oocitos/metabolismo , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oogénesis/genética , Perfilación de la Expresión GénicaRESUMEN
Climate change often includes increases in the occurrence of extreme environmental events. Among these, heatwaves affect the pace of life and performance of wildlife, particularly ectothermic animals, owing to their low thermoregulatory abilities. However, the underlying mechanisms by which this occurs remain unclear. Evidence shows that heatwaves alter the redox balance of ectotherms, and oxidative stress is a major mediator of life-history trade-offs. Therefore, oxidative stress may mediate the effect of extreme thermal conditions on the life histories of ectotherms. To test this hypothesis, a 2 × 2 experiment was conducted to manipulate the redox balance (through a mitochondrial uncoupler that alleviates oxidative stress) of the desert toad-headed agama (Phrynocephalus przewalskii) exposed to heatwave conditions. We recorded lizard growth and survival rates and quantified their redox and immune statuses. In control lizards (unmanipulated redox balance), heatwave conditions decreased growth and survival and induced oxidative damage and immune responses. By contrast, lizards with alleviated oxidative stress showed close-to-normal growth, survival, and immune status when challenged with heatwaves. These results provide mechanistic insight into the role of oxidative stress in mediating the effects of extreme temperatures on ectothermic vertebrates, which may have major eco-evolutionary implications.
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Lagartos , Animales , Lagartos/fisiología , Calor , Cambio Climático , Regulación de la Temperatura Corporal , Estrés OxidativoRESUMEN
Topological edge states are a generic feature of topological insulators, and the long-range interactions, which break certain properties of topological edge states, are always non-negligible in real physical systems. In this Letter, we investigate the influence of next-nearest-neighbor (NNN) interactions on the topological properties of the Su-Schrieffer-Heeger (SSH) model by extracting the survival probabilities at the boundary of the photonic lattices. By introducing a series of integrated photonic waveguide arrays with different strengths of long-range interactions, we experimentally observe delocalization transition of light in SSH lattices with nontrivial phase, which is in good agreement with our theoretical predictions. The results indicate that the NNN interactions can significantly affect the edge states, and that the localization of these states can be absent in topologically nontrivial phase. Our work provides an alternative way to investigate the interplay between long-range interactions and localized states, which may stimulate further interest in topological properties in relevant structures.
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Fotones , Análisis por ConglomeradosRESUMEN
Rotated optical axis waveguides can facilitate on-chip arbitrary wave-plate operations, which are crucial tools for developing integrated universal quantum computing algorithms. In this paper, we propose a unique technique based on femtosecond laser direct writing technology to fabricate arbitrarily rotated optical axis waveguides. First, a circular isotropic main waveguide with a non-optical axis was fabricated using a beam shaping method. Thereafter, a trimming line was used to create an artificial stress field near the main waveguide to induce a rotated optical axis. Using this technique, we fabricated high-performance half- and quarter-wave plates. Subsequently, high-fidelity (97.1%) Pauli-X gate operation was demonstrated via quantum process tomography, which constitutes the basis for the full manipulation of on-chip polarization-encoded qubits. In the future, this work is expected to lead to new prospects for polarization-encoded information in photonic integrated circuits.
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A taxonomic identification using polyphasic approach was performed on strain TH16-21T, which was isolated from the interfacial sediment of Taihu Lake, PR China. Strain TH16-21T was Gram-stain-negative, aerobic, rod-shaped and catalase-positive. Phylogenetic analysis based on the 16S rRNA gene and genomic sequences indicated that strain TH16-21T was classified within the genus of Flavobacterium. The 16S rRNA gene sequence of strain TH16-21T showed the highest similarity to Flavobacterium cheniae NJ-26T (98.9â%). The average nucleotide identity and digital DNA-DNA hybridization values between strain TH16-21T and F. cheniae NJ-26T were 91.2 and 45.9â%, respectively. The respiratory quinone was menaquinone 6. The major cellular fatty acids (>10â%) comprised iso-C15â:â0, iso-C16â:â0, iso-C15â:â1 G and iso-C16â:â0 3-OH. The genomic DNA G+C content was 32.2âmol%. Phosphatidylethanolamine, six amino lipids and three phospholipids were the main polar lipids. Based on the phenotypic features and phylogenetic position, a novel species with the name Flavobacterium lacisediminis sp. nov. is proposed. The type strain is TH16-21T (=MCCC 1K04592T=KACC 22896T).
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Ácidos Grasos , Lagos , Ácidos Grasos/química , Lagos/microbiología , Flavobacterium , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Análisis de Secuencia de ADN , Composición de Base , Técnicas de Tipificación Bacteriana , Vitamina K 2RESUMEN
BACKGROUND: Aflatoxin B1 (AFB1), one of the most prevalent contaminants in human and animal food, impairs the immune system, but information on the mechanisms of AFB1-mediated macrophage toxicity is still lacking. METHODS AND RESULTS: In this study, for the first time, we employed whole transcriptome sequencing technology to explore the molecular mechanism by which AFB1 affects the growth of porcine alveolar macrophages (PAM). We found that AFB1 exposure reduced the proliferative capacity of PAM and prevented cell cycle progression. Based on whole transcriptome analysis, RT-qPCR, ICC and RNAi, we verified the role and regulatory mechanism of the competing endogenous RNA (ceRNA) network in the process of AFB1 exposure affecting the growth of PAM. CONCLUSIONS: We found that AFB1 induced MSTRG.43,583, MSTRG.67,490, MSTRG.84,995, and MSTRG.89,935 to competitively bind miR-219a, miR-30b-3p, and miR-30c-1-3p, eliminating the inhibition of its target genes CACNA1S, RYR3, and PRKCG. This activated the calcium signaling pathway to regulate the growth of PAM. These results provide valuable information on the mechanism of AFB1 exposure induced impairment of macrophage function in humans and animals.
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Aflatoxina B1 , MicroARNs , Humanos , Animales , Porcinos , Aflatoxina B1/toxicidad , Aflatoxina B1/metabolismo , Macrófagos Alveolares/metabolismo , Señalización del Calcio , Macrófagos/metabolismo , MicroARNs/genética , MicroARNs/metabolismoRESUMEN
BACKGROUND: Upstream infection with vaginal flora can develop into tubal endothelial damage and tubal edema, which can lead to tubal obstruction and fallopian tube abscess if left untreated. Fallopian tube abscess in adolescent virgins is very rare, it may lead to long-term or even lifelong complications once it occurred. CASE PRESENTATION: A 12-year-old adolescent virgin with no history of sexual intercourse and previous physical fitness who presented with lower abdominal pain with nausea and vomiting for 22 h, body temperature up to 39.2 °C. Laparoscopic surgery revealed an abscess in the left fallopian tube, the left fallopian tube was surgically removed, successfully treated, and the pus was cultured for escherichia coli. CONCLUSION: It is important to consider possibility of tubal infection in young.
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Enfermedades de las Trompas Uterinas , Laparoscopía , Femenino , Adolescente , Humanos , Niño , Trompas Uterinas/cirugía , Absceso , Enfermedades de las Trompas Uterinas/complicaciones , Enfermedades de las Trompas Uterinas/cirugía , Dolor Abdominal/etiología , Laparoscopía/efectos adversosRESUMEN
BACKGROUND: The basic endoscopic instruments are not suitable for removing calcified or hard discs in patients with thoracic disc herniations (TDH). We describe a percutaneous endoscopic technique for the treatment of calcified TDH using an endoscopic drill system with a T rigid bendable burr. METHODS: Eleven patients (8 males, mean age 42.1 years) with single-segmental calcified TDH were treated with percutaneous endoscopic surgeries. RESULTS: Our technique using this endoscopic drill system with a T rigid bendable burr is safe and effective for the treatment of calcified TDH. CONCLUSIONS: Percutaneous endoscopic decompression using the T rigid bendable burr is a safe and reproducible surgical procedure for the treatment of calcified TDH.
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Desplazamiento del Disco Intervertebral , Masculino , Humanos , Adulto , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/cirugía , Descompresión Quirúrgica/métodos , Resultado del Tratamiento , Vértebras Lumbares/cirugía , Endoscopía/métodos , Vértebras Torácicas/cirugía , Estudios RetrospectivosRESUMEN
Single photon emitters (SPEs) are critical components of photon-based quantum technology. Recently, the interaction between surface plasmons and emitters has attracted increasing attention because of its potential to improve the quality of single-photon sources through stronger light-matter interactions. In this work, we use a hybrid plasmonic probe composed of a fiber taper and silver nanowire to controllably modulate the radiation properties of SPEs with differently oriented polarization. For out-of-plane oriented SPEs such as single CdSe quantum dots, the radiation lifetime could be reduced by a factor as large as seven; for in-plane oriented SPEs such as hBN defect SPEs, the average modulation amplitude varied from 0.69 to 1.23, depending on the position of the probe. The experimental results were highly consistent with the simulations and theory. This work provides an efficient approach for optimizing the properties of SPEs for quantum photonic integration.
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Optical systems provide a new and practical platform for studying Bloch oscillations. This study investigates the fundamental-mode propagation of polarization-dependent Bloch oscillations. By using the three-dimensional properties of femtosecond laser direct writing, we fabricate a polymer-based gradient waveguide array and determine the Bloch oscillations under different polarization inputs by using the birefringence gradient and the equivalent refractive index, thus exhibiting a polarization-dependent Bloch period. Our results provide a new, to the best of our knowledge, paradigm for two-dimensional optical Bloch modes and highlight the influence of optical polarization in the same system, which provides a possibility to observe richer physics related to Bloch oscillations in one structure.
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Edge states in topological phase transitions have been observed in various platforms. To date, verification of the edge states and the associated topological invariant are mostly studied, and yet a quantitative measurement of topological phase transitions is still lacking. Here, we show the direct measurement of edge states and their localization lengths from survival probability. We employ photonic waveguide arrays to demonstrate the topological phase transitions based on the Su-Schrieffer-Heeger model. By measuring the survival probability at the lattice boundary, we show that in the long-time limit, the survival probability is P=(1-e^{-2/ξ_{loc}})^{2}, where ξ_{loc} is the localization length. This length derived from the survival probability is compared with the distance from the transition point, yielding a critical exponent of ν=0.94±0.04 at the phase boundary. Our experiment provides an alternative route to characterizing topological phase transitions and extracting their key physical quantities.
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Probabilidad , Transición de FaseRESUMEN
As an important degree of freedom (d.o.f.) in photonic integrated circuits, the orthogonal transverse mode provides a promising and flexible way to increase communication capability, for both classical and quantum information processing. To construct large-scale on-chip multimode multi-d.o.f.s quantum systems, a transverse mode-encoded controlled-NOT (CNOT) gate is necessary. Here, with the help of our new transverse mode-dependent directional coupler and attenuator, we demonstrate the first multimode implementation of a 2-qubit quantum gate. The ability of the gate is demonstrated by entangling two separated transverse mode qubits with an average fidelity of 0.89±0.02 and the achievement of 10 standard deviations of violations in the quantum nonlocality verification. In addition, a fidelity of 0.82±0.01 is obtained from quantum process tomography used to completely characterize the CNOT gate. Our work paves the way for universal transverse mode-encoded quantum operations and large-scale multimode multi-d.o.f.s quantum systems.
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Thickness reduction or loss of the calcareous eggshell is one of major phenotypic changes in the transition from oviparity to viviparity. Whether the reduction of eggshells in viviparous squamates is associated with specific gene losses is unknown. Taking advantage of a newly generated high-quality genome of the viviparous Chinese crocodile lizard (Shinisaurus crocodilurus), we found that ovocleidin-17 gene (OC-17), which encodes an eggshell matrix protein that is essential for calcium deposition in eggshells, is not intact in the crocodile lizard genome. Only OC-17 transcript fragments were found in the oviduct transcriptome, and no OC-17 peptides were identified in the eggshell proteome of crocodile lizards. In contrast, OC-17 was present in the eggshells of the oviparous Mongolia racerunner (Eremias argus). Although the loss of OC-17 is not common in viviparous species, viviparous squamates show fewer intact eggshell-specific proteins than oviparous squamates. Our study implies that functional loss of eggshell-matrix protein genes may be involved in the reduction of eggshells during the transition from oviparity to viviparity in the crocodile lizard.