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The superconducting gap symmetry is crucial in understanding the underlying superconductivity mechanism. Angle-resolved photoemission spectroscopy (ARPES) has played a key role in determining the gap symmetry in unconventional superconductors. However, it has been considered so far that ARPES can only measure the magnitude of the superconducting gap but not its phase; the phase has to be detected by other phase-sensitive techniques. Here we propose a method to directly detect the superconducting gap sign by ARPES. This method is successfully validated in a cuprate superconductor Bi2Sr2CaCu2O8+δ with a well-known d-wave gap symmetry. When two bands have a strong interband interaction, the resulted electronic structures in the superconducting state are sensitive to the relative gap sign between the two bands. Our present work provides an approach to detect the gap sign and can be applied to various superconductors, particularly those with multiple orbitals like the iron-based superconductors.
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The latest discovery of high temperature superconductivity near 80 K in La3Ni2O7 under high pressure has attracted much attention. Many proposals are put forth to understand the origin of superconductivity. The determination of electronic structures is a prerequisite to establish theories to understand superconductivity in nickelates but is still lacking. Here we report our direct measurement of the electronic structures of La3Ni2O7 by high-resolution angle-resolved photoemission spectroscopy. The Fermi surface and band structures of La3Ni2O7 are observed and compared with the band structure calculations. Strong electron correlations are revealed which are orbital- and momentum-dependent. A flat band is formed from the Ni-3d z 2 orbitals around the zone corner which is ~ 50 meV below the Fermi level and exhibits the strongest electron correlation. In many theoretical proposals, this band is expected to play the dominant role in generating superconductivity in La3Ni2O7. Our observations provide key experimental information to understand the electronic structure and origin of high temperature superconductivity in La3Ni2O7.
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Plants have evolved a sophisticated immunity system for specific detection of pathogens and rapid induction of measured defences. Over- or constitutive activation of defences would negatively affect plant growth and development. Hence, the plant immune system is under tight positive and negative regulation. MAP kinase phosphatase1 (MKP1) has been identified as a negative regulator of plant immunity in model plant Arabidopsis. However, the molecular mechanisms by which MKP1 regulates immune signalling in wheat (Triticum aestivum) are poorly understood. In this study, we investigated the role of TaMKP1 in wheat defence against two devastating fungal pathogens and determined its subcellular localization. We demonstrated that knock-down of TaMKP1 by CRISPR/Cas9 in wheat resulted in enhanced resistance to rust caused by Puccinia striiformis f. sp. tritici (Pst) and powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt), indicating that TaMKP1 negatively regulates disease resistance in wheat. Unexpectedly, while Tamkp1 mutant plants showed increased resistance to the two tested fungal pathogens they also had higher yield compared with wild-type control plants without infection. Our results suggested that TaMKP1 interacts directly with dephosphorylated and activated TaMPK3/4/6, and TaMPK4 interacts directly with TaPAL. Taken together, we demonstrated TaMKP1 exert negative modulating roles in the activation of TaMPK3/4/6, which are required for MAPK-mediated defence signalling. This facilitates our understanding of the important roles of MAP kinase phosphatases and MAPK cascades in plant immunity and production, and provides germplasm resources for breeding for high resistance and high yield.
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Sistemas CRISPR-Cas , Resistencia a la Enfermedad , Enfermedades de las Plantas , Inmunidad de la Planta , Triticum , Triticum/genética , Triticum/microbiología , Triticum/inmunología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Inmunidad de la Planta/genética , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ascomicetos/fisiología , Mutagénesis , Fosfatasa 1 de Especificidad Dual/genética , Fosfatasa 1 de Especificidad Dual/metabolismo , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/genética , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/metabolismo , Puccinia/fisiología , Plantas Modificadas GenéticamenteRESUMEN
Goji berry (wolfberry, Lycium), is a genus of Solanaceae, in which the roots, stems, leaves, and fruits are for both food and medicinal uses. In recent years, the demand for health food and research purposes has led to increasing attention being paid to the application of goji berry nutrients and resources. There are three general strategies to process and utilize the goji berry plant. First, the primary processing of goji berry products, such as dried goji berry pulp, and fruit wine with its by-products. Second, deep processing of sugar-peptides, carotenoids, and the extraction of other efficacy components with their by-products. Third, the utilization of plant-based by-products (roots, stems, leaves, flowers, and fruit residuals). However, the comprehensive use of goji berry is hampered by the non-standardized production technology of resource utilization and the absence of a multi-level co-production and processing technology systems. On the basis of this, we review some novel techniques that are made to more effectively use the resources found in goji berry or its by-products in order to serve as a guide for the thorough use of these resources and the high-quality growth of the goji berry processing industry.
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This study investigated the effect of fiberoptic ductoscopy (FDS) combined with methylene blue staining immediately after FDS procedure on pathological nipple discharge diseases. A retrospective analysis of the clinical data of 122 patients with nipple discharge, who underwent FDS and surgical treatment at the Department of Breast and Thyroid Surgery of Tengzhou Central People's Hospital, was conducted. The demographic characteristics and surgical outcomes of all patients were assessed. According to the injection time of methylene blue, the patients were divided into the control and the observational groups. In the observational group, methylene blue was injected immediately after ductoscopy and then surgical treatment was performed 12-24 h later, while in the control group, methylene blue injection was just few minutes before surgery treatment. There was no significant difference in the demographic characteristics between the two groups such as age and disease course, in the observational group, the incision length 2.39 (0.48) cm, the volume of resected tissue 41.93 (40.57) cm3, the intraoperative blood loss 12.19 (2.10) ml and the operation duration 26.95 (4.51) min were significantly lower than those of the traditional group (P < 0.05). The average hospital stay 3.08 (0.62) days, breast shape satisfaction 4.78 (1.63) points and postoperative drainage tube placement [3 (5.08%) days] in the observational group were significantly better than those in the control group (P < 0.05). FDS combined with immediate methylene blue staining, which has the advantages of accurate location of the diseased duct, small surgical incision, less tissue removal, and ease of finding the orifice of discharged mammary duct, and is worthy of widespread clinical application.
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Neoplasias de la Mama , Secreción del Pezón , Herida Quirúrgica , Humanos , Femenino , Estudios Retrospectivos , Pezones/cirugía , Pezones/patología , Azul de Metileno , Endoscopía/métodos , Herida Quirúrgica/patología , Neoplasias de la Mama/patología , Coloración y EtiquetadoRESUMEN
GATA proteins are a class of zinc-finger DNA-binding proteins that participate in diverse regulatory processes in plants, including the development processes and responses to environmental stresses. However, a comprehensive analysis of the GATA gene family has not been performed in a wolfberry (Lycium barbarum L.) or other Solanaceae species. There are 156 GATA genes identified in five Solanaceae species (Lycium barbarum L., Solanum lycopersicum L., Capsicum annuum L., Solanum tuberosum L., and Solanum melongena L.) in this study. Based on their phylogeny, they can be categorized into four subfamilies (I-IV). Noticeably, synteny analysis revealed that dispersed- and whole-genome duplication contributed to the expansion of the GATA gene family. Purifying selection was a major force driving the evolution of GATA genes. Moreover, the predicted cis-elements revealed the potential roles of wolfberry GATA genes in phytohormone, development, and stress responses. Furthermore, the RNA-seq analysis identified 31 LbaGATA genes with different transcript profiling under salt stress. Nine candidate genes were then selected for further verification using quantitative real-time PCR. The results revealed that four candidate LbaGATA genes (LbaGATA8, LbaGATA19, LbaGATA20, and LbaGATA24) are potentially involved in salt-stress responses. In conclusion, this study contributes significantly to our understanding of the evolution and function of GATA genes among the Solanaceae species, including wolfberry.
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Lycium , Solanum tuberosum , Lycium/genética , Factores de Transcripción GATA/genética , Estrés Salino/genética , Estrés Fisiológico/genética , Solanum tuberosum/genéticaRESUMEN
In conventional superconductors, electron-phonon coupling plays a dominant role in generating superconductivity. In high-temperature cuprate superconductors, the existence of electron coupling with phonons and other boson modes and its role in producing high-temperature superconductivity remain unclear. The evidence of electron-boson coupling mainly comes from angle-resolved photoemission (ARPES) observations of [Formula: see text]70-meV nodal dispersion kink and [Formula: see text]40-meV antinodal kink. However, the reported results are sporadic and the nature of the involved bosons is still under debate. Here we report findings of ubiquitous two coexisting electron-mode couplings in cuprate superconductors. By taking ultrahigh-resolution laser-based ARPES measurements, we found that the electrons are coupled simultaneously with two sharp modes at [Formula: see text]70meV and [Formula: see text]40meV in different superconductors with different dopings, over the entire momentum space and at different temperatures above and below the superconducting transition temperature. These observations favor phonons as the origin of the modes coupled with electrons and the observed electron-mode couplings are unusual because the associated energy scales do not exhibit an obvious energy shift across the superconducting transition. We further find that the well-known "peak-dip-hump" structure, which has long been considered a hallmark of superconductivity, is also omnipresent and consists of "peak-double dip-double hump" finer structures that originate from electron coupling with two sharp modes. These results provide a unified picture for the [Formula: see text]70-meV and [Formula: see text]40-meV energy scales and their evolutions with momentum, doping and temperature. They provide key information to understand the origin of these energy scales and their role in generating anomalous normal state and high-temperature superconductivity.
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OBJECTIVE: To explore the diagnosis, treatment and genetic characteristics of a neonate with severe pulmonary hypertension and respiratory failure. METHODS: Perinatal history, clinical manifestations, laboratory finding and diagnosis and treatment data of the child were collected. Whole exome sequencing was carried out for the child, and Sanger sequencing was used to verify the candidate variants. RESULTS: The female neonate has developed progressive respiratory failure and refractory pulmonary hypertension shortly after birth. Conventional treatment such as mechanical ventilation, vasoactive drugs, and inhaled nitric oxide were ineffective. She has developed sustained pulmonary hypertension after weaning from extracorporeal membrane oxygenation therapy, and had died after the treatment had ceased. Whole exome sequencing revealed that she has harbored a heterozygous de novo variant of c.682_683insGCGGCGGC (p.G234Rfs*148) of the FOXF1 gene, which was predicted as pathogenic based on guidelines from the American College of Medical Genetics and Genomics (ACMG), with evidence items of PVS1_Strong+PM2_Supporting+PS2. Based on her clinical manifestations and result of genetic testing, the child was diagnosed with alveolar capillary dysplasia with misalignment of the pulmonary veins (ACD/MPV). CONCLUSION: Discovery of the c.682_683insGCGGCGGC (p.G234 Rfs*148) variant of the FOXF1 gene has expanded the mutational spectrum of the FOXF1 gene, which has facilitated implementation of specific treatment and provided a basis for clinical diagnosis and genetic counseling.
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Hipertensión Pulmonar , Síndrome de Circulación Fetal Persistente , Venas Pulmonares , Femenino , Humanos , Niño , Recién Nacido , Embarazo , Síndrome de Circulación Fetal Persistente/diagnóstico , Síndrome de Circulación Fetal Persistente/genética , Síndrome de Circulación Fetal Persistente/terapia , Factores de Transcripción Forkhead/genéticaRESUMEN
Kagome lattices of various transition metals are versatile platforms for achieving anomalous Hall effects, unconventional charge-density wave orders and quantum spin liquid phenomena due to the strong correlations, spin-orbit coupling and/or magnetic interactions involved in such a lattice. Here, we use laser-based angle-resolved photoemission spectroscopy in combination with density functional theory calculations to investigate the electronic structure of the newly discovered kagome superconductor CsTi3Bi5, which is isostructural to the AV3Sb5 (A = K, Rb or Cs) kagome superconductor family and possesses a two-dimensional kagome network of titanium. We directly observe a striking flat band derived from the local destructive interference of Bloch wave functions within the kagome lattice. In agreement with calculations, we identify type-II and type-III Dirac nodal lines and their momentum distribution in CsTi3Bi5 from the measured electronic structures. In addition, around the Brillouin zone centre, [Formula: see text] nontrivial topological surface states are also observed due to band inversion mediated by strong spin-orbit coupling.
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PURPOSE: Metastatic early-onset colorectal cancer (EO-CRC) is on the rise, yet there is a dearth of predictive models for this disease. Therefore, it is crucial to develop a nomogram to aid in the early detection and management of metastatic colorectal cancer in young patients. METHODS: We retrieved data from the SEER database on patients with metastatic colorectal cancer aged 50 or younger between 2010 and 2017. The data were randomly allocated in a 7:3 ratio to training and validation cohorts, and univariate and multivariate Cox regression analyses were used to identify independent prognostic factors for overall survival (OS) and cancer-specific survival (CSS) at 1, 3, and 5 years. The nomograms were developed based on these factors, and their discriminatory and calibration capabilities were validated. Using the nomogram risk scores, patients were stratified into low-risk and high-risk groups. RESULTS: The study included 2470 patients with metastatic EO-CRC. Univariate and multivariate Cox regression analysis identified 12 independent risk factors that were included in the nomogram. The training cohort had a consistency index (C-index) of 0.71, while the validation cohort had a C-index of 0.70, demonstrating good predictive accuracy. Calibration plots showed a high level of consistency between the observed and predicted values, with overlapping plots along the diagonal. The decision curve analysis (DCA) revealed that the nomogram had a high clinical application value. CONCLUSIONS: The novel nomograms were created to predict the prognosis of patients with metastatic EO-CRC, which can aid clinicians in developing more effective treatment strategies and contribute to more accurate prognostic assessments.
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Neoplasias del Colon , Neoplasias del Recto , Humanos , Investigación , Nomogramas , Calibración , Programa de VERF , Pronóstico , Estadificación de NeoplasiasRESUMEN
Cell viability, as an important index to evaluate drug effects, usually was measured by tetrazolium colorimetric assay, playing a key role in drug development and drug screening. Tedious operating procedures, unsatisfactory sensitivity and abominable environments perplex researchers to acquire more detailed in vivo-relevant biological information. Herein, a simple and low-cost cell viability and drug evaluation biosensing system-based on multiwalled carbon nanotubes, gold nanoparticles and Nafion modified screen-printed electrode (SPE) biosensor was constructed for detection of dopamine (DA) released from living cells to evaluate cytotoxicity of antineoplastic drugs such as cisplatin and resveratrol. The biosensing system was demonstrated to display exceptional selectivity, excellent flexibility and good stability toward DA measurement in complex bio-samples. Additionally, the satisfactory recoveries of DA in real samples revealed the reliability and accuracy of the biosensing system in practical application. The IC50 curves respectively obtained by the biosensing system and tetrazolium colorimetric assay provided similar IC50 value but distinctly different dose-effect relationship, which confirmed the enormous potential of the biosensor in cell viability and described drug efficacy profiles in cell function. In short, the cell viability and drug evaluation system using SPE biosensor paves a new way in drug screening and pharmaceutical application to measure bioactive molecule such as DA.
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Técnicas Biosensibles , Nanopartículas del Metal , Nanocompuestos , Nanotubos de Carbono , Oro , Dopamina , Supervivencia Celular , Evaluación de Medicamentos , Reproducibilidad de los Resultados , Electrodos , Exocitosis , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodosRESUMEN
This study aimed to evaluate the antibacterial properties of nine lactic acid bacterial strains. The agar diffusion method (Oxford cup method) was used to assess the antimicrobial activity against pathogenic bacteria in aquaculture. The results showed that all selected strains inhibited the growth of Photobacterium damsel, Vibrio alginolyticus, Listonella anguillarum, Edwardsiella ictaluri, Aeromonas hydrophila, V. arahaemolyticus, Edwardsiella tarda and V. harveyi, but did not inhibit the growth of Metschnikowia bicuspidata. Among these strains of lactic acid bacteria, r1 was selected for its obvious antibacterial activity against eight kinds of pathogenic bacteria by 96-well plate method. Its inhibitory rate reached 96%, and it could inhibit the growth of six pathogenic bacteria at 121 â, 20 min and pH 3.5-4.0. It was identified as Lactiplantibacillus plantarum by morphological observation and 16S rRNA sequencing analysis. Because strain r1 was isolated from culture ponds and exerted strong inhibitory effects on pathogenic bacteria, it holds potential as an agent to prevent and control infectious diseases in aquaculture. This study provides a foundation for the development and utilization of probiotics in aquaculture.
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Antiinfecciosos , Enfermedades de los Peces , Lactobacillales , Probióticos , Vibrio , Animales , Lactobacillales/genética , ARN Ribosómico 16S/genética , Acuicultura/métodos , Vibrio/genética , Antiinfecciosos/farmacología , Probióticos/farmacología , Antibacterianos/farmacología , Enfermedades de los Peces/microbiologíaRESUMEN
The control of nitrogenous pollutants is a key concern in aquaculture production. Bacillus spp. are commonly used as probiotics in aquaculture, but only a few reports have focused on the simultaneous heterotrophic nitrification and aerobic denitrification (SND) capacity of Bacillus sp. strains. In order to improve nitrogen biodegradation efficiency in the aquaculture industry, the SND capacity of Bacillus sp. strains was evaluated using both individual and mixed nitrogen sources and different sources of organic carbon. Twelve Bacillus sp. isolates were screened from aquaculture pond sediments and shrimp guts for nitrogen biodegradation. Six strains exhibited especially efficient inorganic nitrogen removal capacities in media with individual and mixed nitrogen sources. These strains comprise K8, N2, and N5 (B. subtilis), HYS (B. albus), H4 (B. amyloliquefaciens), and S1 (B. velezensis). The strains grew better when the sole nitrogen source was NH4+-N, but degraded nitrogen in the following order: nitrite nitrogen (NO2--N), ammonium nitrogen (NH4+-N), and nitrate nitrogen (NO3--N). There was no associated NO2--N accumulation, regardless of the nitrogen source. The optimal carbon source for nitrogen removal varied based on different nitrogen sources and associated metabolic pathways. The optimal carbon sources for the removal of NO3--N, NO2--N, and NH4+-N were sodium citrate, sodium acetate, and sucrose, respectively. The application of H4 in recirculating aquaculture water further demonstrated that NO2--N and NH4+-N could be effectively removed. This study thus provides valuable technical support for the bioremediation of aquaculture water.
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Bacillus , Nitrificación , Aerobiosis , Bacillus/metabolismo , Carbono/metabolismo , Desnitrificación , Procesos Heterotróficos , Nitritos/metabolismo , Nitrógeno/metabolismo , Dióxido de Nitrógeno/metabolismo , AguaRESUMEN
PURPOSE: The application of augmented reality technology to the partial hepatectomy procedure has high practical significance, but the existing augmented reality navigation system has major drawbacks in the display and registration methods, which result in low precision. The augmented reality surgical navigation system proposed in this study has been improved in the above two aspects, which can significantly improve the surgical accuracy. METHODS: The use of optical see-through head-mounted displays for imaging displays can prevent doctors from reconstructing the patient's two-dimensional image information in their minds and reduce the psychological burden of doctors. In the registration process, the biomechanical properties of the liver are introduced, and a non-rigid registration method based on biomechanics is proposed and realized by a meshless algorithm. In addition, this study uses the moving grid algorithm to carry out clinical experiments on ex-vivo pig liver for experimental verification. RESULTS: The mark-based interactive registration error is 4.21 ± 1.6 mm, and the registration error is reduced after taking the biomechanical properties of the liver into account, which is - 0.153 ± 0.398 mm. The cutting error of the liver model is 0.159 ± 0.292 mm. In addition, with the aid of the navigation system proposed in this paper, the experiment of ex-vivo pig liver cutting was completed with an error of - 1.164 ± 0.576 mm. CONCLUSIONS: As a proof-of-concept study, the augmented reality navigation system proposed in this study improves the traditional image-guided surgery in terms of display and registration methods, and the feasibility of the system is verified by ex-vivo pig liver experiments. Therefore, the navigation system has a certain guiding significance for clinical surgery.
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Realidad Aumentada , Cirugía Asistida por Computador , Algoritmos , Animales , Hepatectomía , Imagenología Tridimensional , Porcinos , TecnologíaRESUMEN
BACKGROUND: Lethal respiratory failure is primarily caused by a deficiency of pulmonary surfactant, and is the main cause of neonatal death among preterm infants. Pulmonary surfactant metabolism dysfunction caused by variants in the ABCA3 gene is a rare disease with very poor prognosis. Currently, the mechanisms associated with some ABCA3 variants have been determined, including protein mistrafficking and impaired phospholipid transport. However, some novel variants and their underlying pathogenesis has not been fully elucidated yet. In this study we aimed to identify the genetic features in a family with lethal respiratory failure. METHODS: We studied members of two generations of a Chinese family, including a female proband, her parents, her monozygotic twin sister, and her older sister. Trio whole exome sequencing (WES) were used on the proband and her parents to identify the ABCA3 variants. Sanger sequencing and real-time quantitative polymerase chain reaction (PCR) were used on the monozygotic twin sister of proband to validate the ABCA3 synonymous variant and exon deletion, respectively. The potential pathogenicity of the identified synonymous variant was predicted using the splice site algorithms dbscSNV11_AdaBoost, dbscSNV11_RandomForest, and Human Splicing Finder (HSF). RESULTS: All patients showed severe respiratory distress, which could not be relieved by mechanical ventilation, supplementation of surfactant, or steroid therapy, and died at an early age. WES analysis revealed that the proband had compound heterozygous ABCA3 variants, including a novel synonymous variant c.G873A (p.Lys291Lys) in exon 8 inherited from the mother, and a heterozygous deletion of exons 4-7 inherited from the father. The synonymous variant was consistently predicted to be a cryptic splice donor site that may lead to aberrant splicing of the pre-mRNA by three different splice site algorithms. The deletion of exons 4-7 of the ABCA3 gene was determined to be a likely pathogenic variant. The variants were confirmed in the monozygotic twin sister of proband by Sanger sequencing and qPCR respectively. The older sister of proband was not available to determine if she also carried both ABCA3 variants, but it is highly likely based on her clinical course. CONCLUSIONS: We identified a novel synonymous variant and a deletion in the ABCA3 gene that may be responsible for the pathogenesis in patients in this family. These results add to the known mutational spectrum of the ABCA3 gene. The study of ABCA3 variants may be helpful for the implementation of patient-specific therapies.
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Transportadoras de Casetes de Unión a ATP/genética , Insuficiencia Respiratoria/genética , China , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Linaje , Insuficiencia Respiratoria/mortalidadRESUMEN
BACKGROUND: Health-related quality of life (HRQOL) has become an important part of the evaluation of clinical efficacy and prognosis in gastric cancer. This study aimed to assess the HRQOL of patients with gastric cancer using the a five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) and explore the factors influencing patients' perceived quality of life. For those significant factors, we can take appropriate measures to intervene to extend patient survival and improve the quality of life. METHODS: A cross-sectional questionnaire survey was administered to 243 patients with gastric cancer in the First Affiliated Hospital of Suzhou University from December 2018 to December 2020. HRQOL was measured by the Chinese version of the EQ-5D-5L. Nonparametric test analyses and a Tobit regression model were used to identify the independent variables associated with the EQ-5D-5L utility scores. RESULTS: In this research, the mean score was 0.810, and the median was 0.893. Approximately 25% of patients reported no problems at all in any of the five dimensions. Problems in pain and discomfort were the most frequently reported (64.2%). Nonparametric test analyses showed that patients who did not have health insurance, or who had a history of alcohol use, a family history of cancer, had received surgery only, or had an interval of less than 1 week between taking this survey and their last treatment, demonstrated lower EQ-5D-5L scores. The Tobit regression model confirmed that health insurance, family history, and treatment were significantly associated with EQ-5D-5L scores. CONCLUSIONS: The HRQOL of gastric cancer patients can be measured by EQ-5D-5L, and the results may provide a guide for choosing an appropriate individualized treatment plan.
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Calidad de Vida , Neoplasias Gástricas , China , Estudios Transversales , Estado de Salud , Humanos , Encuestas y CuestionariosRESUMEN
A high-power continuous-wave (CW) ultraviolet (UV) laser at 378 nm from an intracavity frequency-doubled Alexandrite laser has been demonstrated with 638 nm fiber-coupled laser diodes as the pump source. A maximum output power of 2.55 W was obtained, which is the highest power for CW frequency-doubled Alexandrite lasers, to the best of our knowledge, corresponding to the optical-to-optical conversion efficiency of 7.9% from 638 nm pump laser to 378 nm UV laser. The beam quality factors M2 were measured to be 2.19 and 2.47 in x and y directions at UV output power of 1 W, respectively.
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BACKGROUND: Intraoperative deformation and radiation are common problems in spinal surgery. A three-dimensional multi-stage dynamic iterative non-rigid registration method of the spine based on binocular structured light is proposed in this paper to overcome these problems. METHOD: The problem of intraoperative radiation in traditional X-ray and CT is overcome by using binocular structured light. A three-dimensional spinal mask based on binary code is designed to reduce the influence of non-interested regions on the operation. Principal component analysis (PCA) algorithm is used to complete the rough registration between the preoperative CT model of the spine and the reconstructed surface of the intraoperative structured light. A new framework of multi-stage dynamic iterative non-rigid registration of the spine is proposed. The Iterative Closest Point (ICP) algorithm based on bidirectional selection is proposed to complete the single-stage registration of the spine. Then the multi-stage dynamic iterative registration of the spine is completed to solve the problem of large registration error caused by the deformation of the spine. RESULTS: The method proposed in this paper is compared with traditional registration methods, and its application is verified experimentally. The results show that the registration accuracy and time of the proposed method are 0 . 51 ± 0 . 31 mm and 5 . 21 ± 0 . 23 s, respectively. The accuracy of the method is 81.5% and 78.2% higher than that of the contour method and the method of marker points, respectively. CONCLUSIONS: The method can effectively avoid intraoperative radiation, reduce the registration error caused by the deformation of the spine, and has a high practicability.
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Imagenología Tridimensional , Columna Vertebral , Algoritmos , Humanos , Procedimientos Neuroquirúrgicos , Radiografía , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/cirugíaRESUMEN
The electronic structure and superconducting gap structure are prerequisites to establish microscopic theories in understanding the superconductivity mechanism of iron-based superconductors. However, even for the most extensively studied optimally-doped (Ba0.6K0.4)Fe2As2, there remain outstanding controversies on its electronic structure and superconducting gap structure. Here we resolve these issues by carrying out high-resolution angle-resolved photoemission spectroscopy (ARPES) measurements on the optimally-doped (Ba0.6K0.4)Fe2As2 superconductor using both Helium lamp and laser light sources. Our results indicate the "flat band" feature observed around the Brillouin zone center in the superconducting state originates from the combined effect of the superconductivity-induced band back-bending and the folding of a band from the zone corner to the center. We found direct evidence of the band folding between the zone corner and the center in both the normal and superconducting state. Our resolution of the origin of the flat band makes it possible to assign the three hole-like bands around the zone center and determine their superconducting gap correctly. Around the zone corner, we observe a tiny electron-like band and an M-shaped band simultaneously in both the normal and superconducting states. The obtained gap size for the bands around the zone corner (~5.5 meV) is significantly smaller than all the previous ARPES measurements. Our results establish a new superconducting gap structure around the zone corner and resolve a number of prominent controversies concerning the electronic structure and superconducting gap structure in the optimally-doped (Ba0.6K0.4)Fe2As2. They provide new insights in examining and establishing theories in understanding superconductivity mechanism in iron-based superconductors.