RESUMO
Ageing is a critical factor in spinal-cord-associated disorders1, yet the ageing-specific mechanisms underlying this relationship remain poorly understood. Here, to address this knowledge gap, we combined single-nucleus RNA-sequencing analysis with behavioural and neurophysiological analysis in non-human primates (NHPs). We identified motor neuron senescence and neuroinflammation with microglial hyperactivation as intertwined hallmarks of spinal cord ageing. As an underlying mechanism, we identified a neurotoxic microglial state demarcated by elevated expression of CHIT1 (a secreted mammalian chitinase) specific to the aged spinal cords in NHP and human biopsies. In the aged spinal cord, CHIT1-positive microglia preferentially localize around motor neurons, and they have the ability to trigger senescence, partly by activating SMAD signalling. We further validated the driving role of secreted CHIT1 on MN senescence using multimodal experiments both in vivo, using the NHP spinal cord as a model, and in vitro, using a sophisticated system modelling the human motor-neuron-microenvironment interplay. Moreover, we demonstrated that ascorbic acid, a geroprotective compound, counteracted the pro-senescent effect of CHIT1 and mitigated motor neuron senescence in aged monkeys. Our findings provide the single-cell resolution cellular and molecular landscape of the aged primate spinal cord and identify a new biomarker and intervention target for spinal cord degeneration.
Assuntos
Senescência Celular , Quitinases , Microglia , Neurônios Motores , Primatas , Medula Espinal , Animais , Humanos , Biomarcadores/metabolismo , Quitinases/metabolismo , Microglia/enzimologia , Microglia/metabolismo , Microglia/patologia , Neurônios Motores/metabolismo , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/patologia , Primatas/metabolismo , Reprodutibilidade dos Testes , Análise da Expressão Gênica de Célula Única , Medula Espinal/metabolismo , Medula Espinal/patologiaRESUMO
Clean production of hydrogen peroxide (H2O2) with water, oxygen, and renewable energy is considered an important green synthesis route, offering a valuable substitute for the traditional anthraquinone method. Currently, renewable energy-driven production of H2O2 mostly relies on soluble additives, such as electrolytes and sacrificial agents, inevitably compromising the purity and sustainability of H2O2. Herein, we develop a solution plasma catalysis technique that eliminates the need for soluble additives, enabling eco-friendly production of concentrated H2O2 directly from water and O2. Screening over 40 catalysts demonstrates the superior catalytic performance of carbon nitride interacting with discharge plasma in water. High-throughput density functional theory calculations for 68 models, along with machine learning using 29 descriptors, identify cyano carbon nitride (CCN) as the most efficient catalyst. Solution plasma catalysis with the CCN achieves concentrated H2O2 of 20 mmol L-1, two orders of magnitude higher than photocatalysis by the same catalyst. Plasma diagnostics, isotope labeling, and COMSOL simulations collectively validate that the interplay of solution plasma and the CCN accounts for the significantly increased production of singlet oxygen and H2O2 thereafter. Our findings offer an efficient and sustainable pathway for H2O2 production, promising wide-ranging applications across the chemical industry, public health, and environmental remediation.
RESUMO
The interactive effects of obesity and physical inactivity on lipid metabolism and prevalent dyslipidemia are scarcely reported in rural regions. 39029 subjects were obtained from the Henan Rural Cohort, and their metabolic equivalents (METs) of physical activity (PA) were computed. Independent associations of the obesity indices and PA with either lipid indices or prevalent dyslipidemia were analyzed by generalized linear models, and additive effects of obesity and PA on prevalent dyslipidemia were further quantified. Each obesity index was positively associated with total cholesterol, triglyceride, low-density lipoprotein or prevalent dyslipidemia but negatively associated with high-density lipoprotein, whereas the opposite association of PA with either each lipid index or prevalent dyslipidemia was observed. Joint association of PA and each obesity index with each lipid index and prevalent dyslipidemia was observed. Furthermore, the association of each obesity index in association with each lipid index was attenuated by increased PA levels.
Assuntos
Dislipidemias , Metabolismo dos Lipídeos , Humanos , Obesidade/epidemiologia , China/epidemiologia , Exercício Físico , Dislipidemias/epidemiologia , População Rural , LipídeosRESUMO
Given that the incidence of cancer is dramatically increasing nowadays, cancer-related neuropathic pain including tumor-related and therapy-related pain gradually attracts more attention from researchers, which basically behaves as a metabolic-neuro-immune disorder with worse clinical outcomes and prognosis. Among various mechanisms of neuropathic pain, the common underlying one is the activation of inflammatory responses around the injured or affected nerve(s). Innate and adaptive immune reactions following nerve injury together contribute to the regulation of pain. On the other hand, the tumor immune microenvironment involving immune cells, as exemplified by lymphocytes, macrophages, neutrophils and dendritic cells, inflammatory mediators as well as tumor metastasis have added additional characteristics for studying the initiation and maintenance of cancer-related neuropathic pain. Of interest, these immune cells in tumor microenvironment exert potent functions in promoting neuropathic pain through different signaling pathways. To this end, this review mainly focuses on the contribution of different types of immune cells to cancer-related neuropathic pain, aims to provide a comprehensive summary of how these immune cells derived from the certain tumor microenvironment participate in the pathogenesis of neuropathic pain. Furthermore, the clarification of roles of various immune cells in different tumor immune microenvironments associated with certain cancers under neuropathic pain states constitutes innovative biology that takes the pain field in a different direction, and thereby provides more opportunities for novel approaches for the prevention and treatment of cancer-related neuropathic pain.
Assuntos
Dor do Câncer , Neoplasias , Neuralgia , Humanos , Neuralgia/etiologia , Neuralgia/metabolismo , Macrófagos/metabolismo , Microglia/metabolismo , Neutrófilos/metabolismo , Mediadores da Inflamação/metabolismo , Dor do Câncer/metabolismoRESUMO
L -Tyrosine derivatives are widely applied in the pharmaceutical, food, and chemical industries. Their production is mainly confined to chemical synthesis and plant extract. Microorganisms, as cell factories, exhibit promising advantages for valuable chemical production to fulfill the increase in the demand of global markets. Yeast has been used to produce natural products owing to its robustness and genetic maneuverability. Focusing on the progress of yeast cell factories for the production of L -tyrosine derivatives, we summarized the emerging metabolic engineering approaches in building L -tyrosoine-overproducing yeast and constructing cell factories of three typical chemicals and their derivatives: tyrosol, p-coumaric acid, and L -DOPA. Finally, the challenges and opportunities of L -tyrosine derivatives production in yeast cell factories were also discussed.
Assuntos
Saccharomyces cerevisiae , Tirosina , Tirosina/genética , Tirosina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Engenharia Metabólica , Levodopa/genética , Levodopa/metabolismoRESUMO
BACKGROUND: The gut microbiota plays an essential role in maintaining gut homeostasis and improving performance, with the composition of microbial communities visibly differing across different laying stages in hens and significantly correlating with egg production. To gain further insights into the association between microbial community characteristics and laying periods in Hy-Line variety brown and Isa brown laying hens, we conducted a 16S rRNA amplicon sequencing survey. RESULTS: Our result revealed the diversity of bacteria in the early laying period was commonly higher than peak, and in Hy-Line variety brown laying hens were generally higher than Isa brown. Principal coordinate analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA) revealed that the structure and composition of the gut microbiota of laying hens exhibited significant differences among different groups. Phylum Firmicutes, Bacteroidota, Proteobacteria, and Fusobacteriota were found that dominant in the host's feces. Therein, the abundance of Fusobacteriota was higher in the peak period than in the early period, while the abundance of Cyanobacteria in the early period was higher in two breeds of hens. Furthermore, random forest based on machine learning showed that there were several distinctly abundant genera, which can be used as potential biomarkers to differentiate the different groups of laying periods and breeds. In addition, the prediction of biological function indicated the existing discrepancy in microbial function among the microbiota of four groups. CONCLUSIONS: Our findings offer new insights into the bacterial diversity and intestinal flora composition of different strains of laying hens during various laying periods, contributing significantly to the improvement of production performance and the prevention of chicken diseases.
Assuntos
Cianobactérias , Microbioma Gastrointestinal , Microbiota , Animais , Feminino , Microbioma Gastrointestinal/genética , Galinhas/microbiologia , RNA Ribossômico 16S/genética , Cianobactérias/genéticaRESUMO
Introducing phase transition materials to random systems provides a promising route to create new optoelectronic functionalities of random lasers. Here, a phase transition random laser with switchable lasing modes is reported, which is designed with a thermoresponsive hydrogel as scattering medium. By manipulating the phase transition in hydrogel, random lasing modes can be switched reversibility between incoherent and coherent random lasing. The phenomenon derives from the changing of light scattering properties in different phase states, thus affecting the optical feedback path of random lasing. Besides, based on its controllable and easily detectable time-domain characteristics, the phase transition random laser is applied in information encoding and transmission. It is the first time that the transition from coherent to incoherent random lasing is observed by varying the sample phase states. This work will inspire the design and application of novel random lasers in photoelectric device.
RESUMO
BACKGROUND: This study presented the mortality trend of ischemic heart disease (IHD) in Chinese residents from 2010 to 2019 and provided a basis for further establishment of relevant interventions. METHODS: Data, such as sex, age, urban and rural areas, and death status, were extracted from the China Death Surveillance Dataset from 2010 to 2019, with mortality and age-adjusted death rates (AADRs) as the main indicators. The joinpoint regression model was used to analyze mortality and AADRs trends in IHD. A semi-structured expert interview was conducted to propose targeted intervention measures and countermeasures. RESULTS: We observed an overall upward trend in IHD mortality rates and AADRs in China from 2010 to 2019 (average annual percentage change [AAPC] = 5.14%, AAPCAADRs = 1.60%, P < 0.001). Mortality rates and AADRs increased for both males (AAPC = 4.91%, AAPCAADRs = 1.09%, P < 0.05) and females (AAPC = 5.57%, AAPCAADRs = 1.84%, P < 0.001), with higher mortality rate for males than females but higher variation for females than males. Urban (AAPC = 4.80%, AAPCAADRs = 1.76%, P < 0.05) and rural (AAPC = 5.31%, P < 0.001; AAPCAADRs = 0.99%, P > 0.05) mortality rates increased, with the mortality rate higher in rural areas than in urban areas. In the age analysis, mortality rate was higher in middle-aged and older adults than in other age groups. The age-sex cross-analysis found the highest trend in mortality rates among females aged ≥ 75 years (annual percentage change [APC] = 2.43%, P < 0.05). CONCLUSIONS: The upward trend in IHD mortality in China from 2010 to 2019, especially among female residents aged ≥ 75 years, poses continuing challenges to public health policies and actions.
Assuntos
Isquemia Miocárdica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China/epidemiologia , Mortalidade , Isquemia Miocárdica/mortalidade , População Rural , População Urbana , População do Leste AsiáticoRESUMO
INTRODUCTION: This research aims to explore the expression levels of microRNA (miRNA)-300/BCL-2-like protein 11 (BCL2L11) and their values in the clinical diagnosis of papillary thyroid cancer (PTC). METHODS: Pathological tissues that were surgically removed for thyroid disease were selected. miR-300 and BCL2L11 expression levels in the samples were measured. Receiver operating characteristic (ROC) curves were plotted to analyze miR-300 and BCL2L11 predictive values for PTC. Upon silencing miR-300 and silencing BCL2L11 in PTC cells, the corresponding miR-300 and BCL2L11 expression levels were tested, followed by examining PTC cell activities. The targeting relationship of miR-300 and BCL2L11 was detected by the bioinformatics website and luciferase activity assay. RESULTS: miR-300 expression levels were elevated and BCL2L11 expression levels were reduced in PTC tissues. miR-300 and BCL2L11 expression levels in PTC tissues had a correlation with TNM stage and lymph node metastasis. The results of ROC curve revealed that both miR-300 and BCL2L11 had clinical predictive values for PTC. Mechanistically, miR-300 negatively regulated BCL2L11. The functional assays unveiled that silencing miR-300 impeded PTC cell activities, and silencing BCL2L11 induced PTC cell activities. In the rescue experiment, silencing BCL2L11 reversed the impacts of silencing miR-300 on PTC cell development. CONCLUSION: This study underlines that miR-300 expression is increased and BCL2L11 expression is declined in PTC. miR-300 and BCL2L11 both have clinical predictive values for diagnosing PTC.
Assuntos
Carcinoma Papilar , MicroRNAs , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , MicroRNAs/genética , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Proteína 11 Semelhante a Bcl-2 , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/genética , Linhagem Celular Tumoral , Proliferação de Células , Movimento CelularRESUMO
Giardia duodenum (G. duodenalis) can cause giardiasis and infect a variety of hosts. So far, there have been no detailed data regarding the positive rate of G. duodenalis in cattle in China. Here, a systematic literature review was carried out to investigate the epidemiology of bovine G. duodenalis in China. To perform the meta-analysis, the databases China National Knowledge Infrastructure, VIP Chinese Journal Databases, WanFang Databases, PubMed, and ScienceDirect were employed for screening studies related to the prevalence of G. duodenalis in cattle in China. The total prevalence of G. duodenalis in cattle was estimated to be 8.00% (95% confidence interval [CI]: 5.51-11.62). In the age subgroup, the prevalence of G. duodenalis in calves (11.72%; 95% CI: 7.75-17.73) was significantly higher than that in cattle of other age groups. An analysis based on seasons showed that the prevalence of G. duodenalis in cattle was higher in summer (9.69%; 95% CI: 2.66-35.30) than that in other seasons. The prevalence of G. duodenalis in cattle in 2016 or later was 11.62% (95% CI: 6.49-20.79), which was significantly higher than that before 2016 (3.65%; 95% CI: 2.17-6.12). The highest prevalence of G. duodenalis in cattle was 74.23% (95% CI: 69.76-78.45) recorded in South China. The NOAA's National Center for Environmental Information (https://gis.ncdc.noaa.gov/maps/ncei/cdo/monthly) was used to extract relevant geoclimatic data (latitude, longitude, elevation, temperature, precipitation, humidity, and climate). By analyzing the data of each subgroup, it was shown that age of cattle, sampling year, province, region, temperature, and climate were potential risk factors for giardiasis prevalence in cattle. Based on the analysis of common factors and geographical factors, it is recommended to strengthen effective management measures (e.g., ventilation and disinfection in warm and humid areas) and formulate relevant policies according to local conditions. Breeders should pay more attention to the detection of G. duodenalis in calves, to prevent giardiasis prevalence in cattle of different ages, thereby reducing the economic losses of animal husbandry in China.
Assuntos
Doenças dos Bovinos , Giardia lamblia , Giardíase , Animais , Bovinos , Giardíase/epidemiologia , Giardíase/veterinária , Prevalência , Doenças dos Bovinos/epidemiologia , China/epidemiologia , Fezes , GenótipoRESUMO
We report a supramolecular naphthalene diimide (NDI) radical anion with efficient NIR-II photothermal conversion for E.â coli-responsive photothermal therapy. The supramolecular radical anion (NDI-2CB[7])â - , which is obtained from the E.â coli-induced in situ reduction of NDI-2CB[7] neutral complex, formed by the host-guest interaction between an NDI derivative and cucurbit[7]uril (CB[7]), exhibits unexpectedly strong NIR-II absorption and remarkable photothermal conversion capacity in aqueous solution. The NIR-II absorption is caused by the self-assembly of NDI radical anions to form supramolecular dimer radicals in aqueous solution, which is supported by theoretically predicted spectra. The (NDI-2CB[7])â - demonstrates excellent NIR-II photothermal antimicrobial activity (>99 %). This work provides a new approach for constructing NIR-II photothermal agents and non-contact treatments for bacterial infections.
Assuntos
Escherichia coli , Terapia Fototérmica , Ânions , Imidas/farmacologiaRESUMO
Endoplasmic reticulum (ER) stress, caused by overproduction of reactive oxygen species (ROS), has been shown to be responsible for immunogenic cell death (ICD). Seeking ROS generator targeting ER is an optimal solution to efficiently induce ER stress. Despite clear indications of demand for ER-targeting photosensitizer, the alternative chemical tools remain limited. Herein, the first ER-localizable ICD photoinducer using thio-pentamethine cyanine dye (TCy5) to induce ER stress under mild near-infrared (NIR) irradiation has been developed. Within the ICD photoinducer design, polyfluorinated TCy5-Ph-3F possesses a selective tropism to ER accumulation and superior ROS generation capability in both normoxia and hypoxia conditions, which benefit from its low singlet-triplet gaps. Under NIR irradiation, cancer cells stained by TCy5-Ph-3F will lead to ER stress and induce massive emission of damage-associated molecular patterns, including calreticulin and heat-shock protein 70 exposure, high mobility group box 1 efflux, and adenosine triphosphate secretion. Dendritic cells maturation and CD8+ T cells activation in vivo also highlight the effectiveness. Therefore, the growth of abscopal tumors was substantially suppressed by the primary tumor treated with TCy5-Ph-3F and NIR irradiation. These results confer practical applicability that could provide a guideline for designing efficient ICD photoinducers, which will enable expanding organic molecular applications for cancer immunotherapy.
Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Morte Celular , Linhagem Celular Tumoral , Corantes , Estresse do Retículo Endoplasmático , Morte Celular Imunogênica , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismoRESUMO
PURPOSE: We report two cases diagnosed as acute necrotizing encephalopathy (ANE) with acute onset and various clinical manifestations. METHODS: The patients' data were obtained from the medical records of the Binzhou Medical University Hospital in Binzhou, China. The clinical symptoms, laboratory examination, neuroimaging, treatment, and prognosis of the 2 patients were collected and analyzed. RESULTS: We report 2 adult ANE patients with acute onset. The first symptom was fever, followed by symptoms and signs of damage to the central nervous system. The patients were infected with herpes simplex virus and influenza virus, respectively. The main manifestation on brain magnetic resonance imaging was a mixed-signal of a "three-layer structure" in the bilateral thalamus. The first patient died. Based on the experience of the diagnosis and treatment of the first patient, combined with a review of the literature, the second patient was immediately treated with glucocorticoid pulse therapy combined with gamma globulin injection. This patient's condition was controlled, and the prognosis was good. CONCLUSIONS: This study describes the clinical symptoms, laboratory examination, neuroimaging evidence, and treatment experience of ANE in adults. We believe that the progress of the disease may be controlled, and the prognosis may be improved if glucocorticoid pulse therapy combined with gamma globulin injection is used as soon as possible.
Assuntos
Encefalopatias , Glucocorticoides , Humanos , Adulto , Encefalopatias/diagnóstico , Encefalopatias/patologia , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , gama-GlobulinasRESUMO
The mudskipper Boleophthalmus pectinirostris inhabits intertidal mudflats, exhibiting semilunar reproductive rhythms. To investigate whether melanopsin is possibly involved in the synchronization of the semilunar spawning rhythm in the female mudskipper, we first cloned all four melanopsin subtypes (opn4m1, opn4m3, opn4x1, opn4x2) in B. pectinirostris. Results from RTq-PCR showed that significantly higher transcription levels of all four melanopsin subtypes were observed in the eyes rather than other tissues. In brain, all four melanopsin subtypes were also detectable in different regions, including the telencephalon, in which the expression of melanopsin has not been reported in other teleosts. The transcription levels of opn4m3 and opn4x1 in the telencephalon exhibited a daily fluctuation pattern. When females entered the spawning season, opn4m1 and opn4x1 transcript levels increased significantly in the telencephalon. During the spawning season, the transcript levels of opn4m3 and opn4x1 in the telencephalon appeared to have a cyclic pattern associated with semilunar periodicity, exhibiting two cycles with a peak around the first or the last lunar quarters. Results from ISH showed that, opn4x1 mRNA was localized in the medial of dorsal telencephalic area, dorsal nucleus of ventral telencephalic area (Vd), ventral nucleus of ventral telencephalic area (Vv), anterior part of parvocellular preoptic nucleus, magnocellular part of the magnocellular preoptic nucleus (PMmc), habenular and ventral zone of hypothalamus. Intriguingly, gnrh3 mRNA was also located in Vd, Vv and PMmc. Taken together, our results suggested that melanopsins, e.g. opn4x1, expressed in the telencephalon might mediate semilunar spawning activity in the female mudskipper.
Assuntos
Perciformes , Animais , Feminino , Lua , Perciformes/genética , Perciformes/metabolismo , Opsinas de Bastonetes/metabolismo , Telencéfalo/metabolismoRESUMO
Low-dimensional nanomaterials, such as one-dimensional (1D) nanomaterials and layered 2D materials, have exhibited significance for their respective unique electronic and optoelectronic properties. Here we show that a mixed-dimensional heterostructure with building blocks from multiple dimensions will present a synergistic effect on photodetection. A carbon nanotube (CNT)-[Formula: see text]-graphene photodetector is representative on this issue. Its spatial resolution can be electrically switched between high-resolution mode (HRM) and low-resolution mode (LRM) revealed by scanning photocurrent microscopy (SPCM). The reconfigurable spatial resolution can be attributed to the asymmetric geometry and the gate-tunable Fermi levels of these low-dimensional materials. Significantly, an interference fringe with 334 nm in period was successfully discriminated by the device working at HRM, confirming the efficient electrical control. Electrical control of spatial resolution in CNT-[Formula: see text]-graphene devices reveals the potential of the mixed-dimensional architectures in future nanoelectronics and nano-optoelectronics.
RESUMO
Echinococcosis is a foodborne parasitic zoonosis caused by the larvae of Echinococcus. This disease can affect goats and other mammals. In this study, a systematic review and meta-analysis for echinococcosis in global goats were performed based on the following five databases (China National Knowledge Infrastructure [CNKI], VIP Chinese Journal Database, Wanfang Data, PubMed, and ScienceDirect). In total, 108,197 samples were collected. The global prevalence of echinococcosis in goats was identified to be 10.85% (3217/108,197). The prevalence of echinococcosis in goats was 6.16% (1369/22,208) and 13.27% (874/5932) in South America and Africa, respectively. The prevalence of echinococcosis in goats before 2010 (9.76%; 112/713) was significantly higher than that from 2010 to 2014 (1.44%; 45/32,145) or after 2014 (2.95%; 154/3889). The prevalence of echinococcosis in goats aged <12 months (4.48%; 70/2911) was higher than that in goats aged ≥12 months (2.88%; 36/819). We also investigated the effects of geographical factors and climates on the prevalence of echinococcosis in goats. The results showed that the prevalence of echinococcosis was higher in the areas with high altitude and cold climate. This meta-analysis indicated that echinococcosis was ubiquitous in goats. Thus, we should improve the feeding conditions for goats, and strengthen the control measures of echinococcosis epidemic in goats, with the aims of reducing the economic losses of animal husbandry and providing protection for humans in the aspects of food security and health.
Assuntos
Equinococose , Cabras , Animais , Humanos , Cabras/parasitologia , Prevalência , Equinococose/epidemiologia , Equinococose/veterinária , Equinococose/parasitologia , Zoonoses/epidemiologia , China/epidemiologiaRESUMO
Phononic crystals (PnCs) have attracted much attention due to their great potential for dissipation engineering and propagation manipulation of phonons. Notably, the excellent electrical and mechanical properties of graphene make it a promising material for nanoelectromechanical resonators. Transferring a graphene flake to a prepatterned periodic mechanical structure enables the realization of a PnC with on-chip scale. Here, we demonstrate a nanoelectromechanical periodic array by anchoring a graphene membrane to a 9 × 9 array of standing nanopillars. The device exhibits a quasi-continuous frequency spectrum with resonance modes distributed from â¼120 MHz to â¼980 MHz. Moreover, the resonant frequencies of these modes can be electrically tuned by varying the voltage applied to the gate electrode sitting underneath. Simulations suggest that the observed band-like spectrum provides an experimental evidence for PnC formation. Our architecture has large fabrication flexibility, offering a promising platform for investigations on PnCs with electrical accessibility and tunability.
RESUMO
Nuclear spins in the solid state are both a cause of decoherence and a valuable resource for spin qubits. In this work, we demonstrate control of isolated 29Si nuclear spins in silicon carbide (SiC) to create an entangled state between an optically active divacancy spin and a strongly coupled nuclear register. We then show how isotopic engineering of SiC unlocks control of single weakly coupled nuclear spins and present an ab initio method to predict the optimal isotopic fraction that maximizes the number of usable nuclear memories. We bolster these results by reporting high-fidelity electron spin control (F = 99.984(1)%), alongside extended coherence times (Hahn-echo T2 = 2.3 ms, dynamical decoupling T2DD > 14.5 ms), and a >40-fold increase in Ramsey spin dephasing time (T2*) from isotopic purification. Overall, this work underlines the importance of controlling the nuclear environment in solid-state systems and links single photon emitters with nuclear registers in an industrially scalable material.
RESUMO
BACKGROUND: Breast cancer is one of the most serious diseases threatening women's health. Early screening based on ultrasound can help to detect and treat tumours in the early stage. However, due to the lack of radiologists with professional skills, ultrasound-based breast cancer screening has not been widely used in rural areas. Computer-aided diagnosis (CAD) technology can effectively alleviate this problem. Since breast ultrasound (BUS) images have low resolution and speckle noise, lesion segmentation, which is an important step in CAD systems, is challenging. RESULTS: Two datasets were used for evaluation. Dataset A comprises 500 BUS images from local hospitals, while dataset B comprises 205 open-source BUS images. The experimental results show that the proposed method outperformed its related classic segmentation methods and the state-of-the-art deep learning model RDAU-NET. Its accuracy (Acc), Dice similarity coefficient (DSC) and Jaccard index (JI) reached 96.25%, 78.4% and 65.34% on dataset A, and its Acc, DSC and sensitivity reached 97.96%, 86.25% and 88.79% on dataset B, respectively. CONCLUSIONS: We proposed an adaptive morphological snake based on marked watershed (AMSMW) algorithm for BUS image segmentation. It was proven to be robust, efficient and effective. In addition, it was found to be more sensitive to malignant lesions than benign lesions. METHODS: The proposed method consists of two steps. In the first step, contrast limited adaptive histogram equalization (CLAHE) and a side window filter (SWF) are used to preprocess BUS images. Lesion contours can be effectively highlighted, and the influence of noise can be eliminated to a great extent. In the second step, we propose adaptive morphological snake (AMS). It can adjust the working parameters adaptively according to the size of the lesion. Its segmentation results are combined with those of the morphological method. Then, we determine the marked area and obtain candidate contours with a marked watershed (MW). Finally, the best lesion contour is chosen by the maximum average radial derivative (ARD).
Assuntos
Ultrassonografia Mamária , Algoritmos , Feminino , HumanosRESUMO
BACKGROUND: The rapid development of artificial intelligence technology has improved the capability of automatic breast cancer diagnosis, compared to traditional machine learning methods. Convolutional Neural Network (CNN) can automatically select high efficiency features, which helps to improve the level of computer-aided diagnosis (CAD). It can improve the performance of distinguishing benign and malignant breast ultrasound (BUS) tumor images, making rapid breast tumor screening possible. RESULTS: The classification model was evaluated with a different dataset of 100 BUS tumor images (50 benign cases and 50 malignant cases), which was not used in network training. Evaluation indicators include accuracy, sensitivity, specificity, and area under curve (AUC) value. The results in the Fus2Net model had an accuracy of 92%, the sensitivity reached 95.65%, the specificity reached 88.89%, and the AUC value reached 0.97 for classifying BUS tumor images. CONCLUSIONS: The experiment compared the existing CNN-categorized architecture, and the Fus2Net architecture we customed has more advantages in a comprehensive performance. The obtained results demonstrated that the Fus2Net classification method we proposed can better assist radiologists in the diagnosis of benign and malignant BUS tumor images. METHODS: The existing public datasets are small and the amount of data suffer from the balance issue. In this paper, we provide a relatively larger dataset with a total of 1052 ultrasound images, including 696 benign images and 356 malignant images, which were collected from a local hospital. We proposed a novel CNN named Fus2Net for the benign and malignant classification of BUS tumor images and it contains two self-designed feature extraction modules. To evaluate how the classifier generalizes on the experimental dataset, we employed the training set (646 benign cases and 306 malignant cases) for tenfold cross-validation. Meanwhile, to solve the balance of the dataset, the training data were augmented before being fed into the Fus2Net. In the experiment, we used hyperparameter fine-tuning and regularization technology to make the Fus2Net convergence.