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BACKGROUND & AIMS: Men are more prone to develop and die from liver fibrosis than women. In this study, we aim to investigate how sex-determining region Y gene (SRY) in hepatocytes promotes liver fibrosis. METHODS: Hepatocyte-specific Sry knock-in (KI), Sry knockout (KO), and Sry KI with platelet-derived growth factor receptor α (Pdgfrα) KO mice were generated. Liver fibrosis was induced in mice by bile duct ligation for 2 weeks or carbon tetrachloride treatment for 6 weeks. In addition, primary hepatocytes, hepatic stellate cells (HSCs), and immortalized cell lines were used for in vitro studies and mechanistic investigation. RESULTS: Compared to females, the severity of toxin- or cholestasis-induced liver fibrosis is similarly increased in castrated and uncastrated male mice. Among all Y chromosome-encoded genes, SRY was the most significantly upregulated and consistently increased gene in fibrotic/cirrhotic livers in male patients and in mouse models. Sry KI mice developed exacerbated liver fibrosis, whereas Sry KO mice had alleviated liver fibrosis, compared to age- and sex-matched control mice after bile duct ligation or administration of carbon tetrachloride. Mechanistically, both our in vivo and in vitro studies illustrated that SRY in hepatocytes can transcriptionally regulate Pdgfrα expression, and promote HMGB1 (high mobility group box 1) release and subsequent HSC activation. Pdgfrα KO or treatment with the SRY inhibitor DAX1 in Sry KI mice abolished SRY-induced HMGB1 secretion and liver fibrosis. CONCLUSIONS: SRY is a strong pro-fibrotic factor and accounts for the sex disparity observed in liver fibrosis, suggesting its critical role as a potentially sex-specific therapeutic target for prevention and treatment of the disease. IMPACT AND IMPLICATION: We identified that a male-specific gene, sex-determining region Y gene (SRY), is a strong pro-fibrotic gene that accounts for the sex disparity observed in liver fibrosis. As such, SRY might be an appropriate target for surveillance and treatment of liver fibrosis in a sex-specific manner. Additionally, SRY might be a key player in the sexual dimorphism observed in hepatic pathophysiology more generally.
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Células Estrelladas Hepáticas , Hepatocitos , Cirrosis Hepática , Proteína de la Región Y Determinante del Sexo , Animales , Femenino , Masculino , Ratones , Tetracloruro de Carbono/toxicidad , Tetracloruro de Carbono/efectos adversos , Colestasis/genética , Colestasis/metabolismo , Colestasis/fisiopatología , Modelos Animales de Enfermedad , Células Estrelladas Hepáticas/metabolismo , Hepatocitos/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Ratones Noqueados , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Caracteres Sexuales , Proteína de la Región Y Determinante del Sexo/genética , Proteína de la Región Y Determinante del Sexo/metabolismoRESUMEN
OBJECTIVES: To define how dynamic changes in pre- versus post-operative serum aspartate aminotransferase (AST) and alanine aminotransaminase (ALT) levels may impact postoperative morbidity after curative-intent resection of hepatocellular carcinoma (HCC). BACKGROUND: Hepatic ischemia/reperfusion can occur at the time of liver resection and may be associated with adverse outcomes following liver resection. METHODS: Patients who underwent curative resection for HCC between 2010-2020 were identified from an international multi-institutional database. Changes in AST and ALT (CAA) on postoperative day (POD) 3 versus preoperative values () were calculated using the formula: based on a fusion index via Euclidean norm, which was examined relative to the comprehensive complication index (CCI). The impact of CAA on CCI was assessed by the restricted cubic spline regression and Random Forest analyses. RESULTS: A total of 759 patients were included in the analytic cohort. Median CAA was 1.7 (range, 0.9 to 3.25); 431 (56.8%) patients had a CAA<2, 215 (28.3%) patients with CAA 2-5, and 113 (14.9%) patients had CAA ≥5. The incidence of post-operative complications was 65.0% (n=493) with a median CCI of 20.9 (IQR, 20.9-33.5). Spline regression analysis demonstrated a non-linear incremental association between CAA and CCI. The optimal cutoff value of CAA=5 was identified by the recursive partitioning technique. After adjusting for other competing risk factors, CAA≥5 remained strongly associated with risk of post-operative complications (Ref. CAA<5, OR 1.63, 95%CI 1.05-2.55, P=0.03). In fact, the use of CAA to predict post-operative complications was very good in both the derivative (AUC 0.88) and external (ACU 0.86) cohorts (n=1137). CONCLUSIONS: CAA was an independent predictor of CCI after liver resection for HCC. Use of routine labs such as AST and ALT can help identify patients at highest risk of post-operative complications following HCC resection.
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OBJECTIVE: To investigate the effect of bone cement on the vertebral body and biomechanical properties in percutaneous cement discoplasty (PCD) for degenerative lumbar disc disease. METHODS: Three-dimensional reconstruction of L2 ~ L3 vertebral bodies was performed in a healthy volunteer, and the corresponding finite element model of the spine was established. Biomechanical analysis was performed on the changes in stress distribution in different groups of models by applying quantitative loads. RESULTS: Models with percutaneous discoplasty (PCD) showed improved stability under various stress conditions, and intervertebral foraminal heights were superior to models without discoplasty. CONCLUSION: Cement discoplasty can improve the stability of the vertebral body to a certain extent and restore a certain height of the intervertebral foramen, which has a good development prospect and potential.
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Escoliosis , Humanos , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Análisis de Elementos Finitos , Cementos para Huesos/uso terapéutico , Columna Vertebral , Voluntarios SanosRESUMEN
A series of side-chain liquid crystalline polymers P4VP(CN-DBE)x , where x is the molar ratio of cyanostilbene (CN-DBE) to poly(4-vinylpyridine) (P4VP) repeating unit, was synthesized based on the intermolecular hydrogen bonding between P4VP and CN-DBE. Their luminescent property, liquid crystalline structure and photo-thermo-electric property were elucidated using photoluminescence spectra, X-ray diffraction, thermal imaging and thermoelectric experiments. With the increase of x, the supramolecular system can be changed from lamellar structure to hexagonal columnar structure. Moreover, the P4VP(CN-DBE)x polymer with columnar structure exhibits more efficient photothermal effect. The temperature of P4VP(CN-DBE)0.6 can rise to 130 °C within 10â s under the irradiation of ultraviolet lamp. In addition, the supramolecular system possesses unique photo-thermo-electric conversion ability, and 25â mA current can be detected in the circuit coupled with the thermoelectric module. This work broadens the potential applications of hydrogen-bonded polymer, and provides a simple and facile strategy to prepare liquid crystalline polymers with photo-thermo-electric property.
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Zeolite is considered an ideal catalyst for olefin hydration due to its high specific surface area and abundant acid sites. However, the immiscibility of the water-oil two phases in olefin hydration limits mass transfer, and the side reaction of etherification occurs acutely, resulting in a low yield of alcohol. Thus, water-oil amphiphilic HZSM-5 was prepared by sulfonating silanized zeolite. The successful introduction of organic and sulfonic acid groups is demonstrated by FT-IR, TG, and water contact angles. Amphiphilic HZSM-5 can stabilize the Pickering emulsion and catalyze cyclopentene hydration at the phase interface. In addition, NH3-TPD and Py-IR show that the amount of strong BroÌ·nsted acid sites of zeolites increases significantly after sulfonation. This facilitates the rate-determining step of cyclopentene activation by H+ to form carbocation. Moreover, the nucleophilic side reactions are inhibited by a high concentration of H+. Finally, under the optimized reaction condition, the conversion of cyclopentene can achieve 5.066% with a selectivity of 85.37% to cyclopentanol, which almost reaches the reaction equilibrium.
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Two zero-dimensional inorganic-organic hybrids, namely, [C4mim][Cd(TCDPPA)3] (1) and [C4mpy][Cd(TCDPPA)3] (2), where (TCDPPA)- = 2,2,2-trichloro-N-(di(pyrrolidin-1-yl)phosphoryl)acetamide, (C4mim)+ = 1-butyl-3-methylimidazolium, and (C4mpy)+ = 1-butyl-4-methylpyridinium, have been synthesized via metathesis reactions and characterized systematically. These ionic cadmium-containing inorganic-organic hybrid compounds are assembled from a bulky organic cation and a complex anion constructed from the chelation of three TCDPPA ligands to one cadmium ion. These compounds possess wide band gaps and emit in the deep-blue region intensely with a quantum yield as high as 34.04%. The success of this work provides a new method for the design and fabrication of high-efficiency blue-emitting materials.
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BACKGROUND: Carotid vulnerable plaque is an important risk factor for stroke occurrence and recurrence. However, the relationship between risk parameters related to carotid vulnerable plaque (plaque size, echogenicity, intraplaque neovascularization, and plaque stiffness) and neurological outcome after ischemic stroke or TIA is unclear. This study investigates the value of multimodal ultrasound-based carotid plaque risk biomarkers to predict poor short-term functional outcome after ischemic stroke or TIA. METHODS: This study was a single-center, prospective, continuous, cohort study to observe the occurrence of adverse functional outcomes (mRS 2-6/3-6) 90 days after ischemic stroke or TIA in patients, where the exposure factors in this study were carotid plaque ultrasound risk biomarkers and the risk factors were sex, age, disease history, and medication history. Patients with ischemic stroke or TIA (mRS ≤3) whose ipsilateral internal carotid artery stenosis was ≥50% within 30 days were included. All patients underwent multimodal ultrasound at baseline, including conventional ultrasound, superb microvascular imaging (SMI), and shear wave elastography (SWE). Continuous variables were divided into four groups at interquartile spacing for inclusion in univariate and multifactorial analyses. After completion of a baseline ultrasound, all patients were followed up at 90 days after ultrasound, and patient modified neurological function scores (mRSs) were recorded. Multivariate Cox regression and ROC curves were used to assess the risk factors and predictive power for predicting poor neurological function. RESULTS: SMI revealed that 20 (30.8%) patients showed extensive neovascularization in the carotid plaque, and 45 (69.2%) patients showed limited neovascularization in the carotid plaque. SWE imaging showed that the mean carotid plaque stiffness was 51.49 ± 18.34 kPa (23.19-111.39 kPa). After a mean follow-up of 90 ± 14 days, a total of 21 (32.3%) patients had a mRS of 2-6, and a total of 10 (15.4%) patients had a mRS of 3-6. Cox regression analysis showed that the level of intraplaque neovascularization and plaque stiffness were independent risk factors for a mRS of 2-6, and the level of intraplaque neovascularization was an independent risk factor for a mRS of 3-6. After correcting for confounders, the HR of intraplaque neovascularization level and plaque stiffness predicting a mRS 2-6 was 3.06 (95% CI 1.05-12.59, P = 0.041) and 0.51 (95% CI 0.31-0.83, P = 0.007), respectively; the HR of intraplaque neovascularization level predicting a mRS 3-6 was 6.11 (95% CI 1.19-31.45, P = 0.031). For ROC curve analysis, the mRSs for intraplaque neovascularization level, plaque stiffness, and combined application to predict 90-day neurological outcome ranged from 2 to 6, with AUCs of 0.73 (95% CI 0.59-0.87), 0.76 (95% CI 0.64-0.89) and 0.85 (95% CI 0.76-0.95), respectively. The mRSs for the intraplaque neovascularization level to predict 90-day neurological outcome ranged from 3 to 6, with AUCs of 0.79 (95% CI 0.63-0.95). CONCLUSION: Intraplaque neovascularization level and plaque stiffness may be associated with an increased risk of poor short-term functional outcome after stroke in patients with recent anterior circulation ischemic stroke due to carotid atherosclerosis. The combined application of multiple parameters has efficacy in predicting poor short-term functional outcome after stroke.
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Estenosis Carotídea , Ataque Isquémico Transitorio , Accidente Cerebrovascular Isquémico , Placa Aterosclerótica , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/epidemiología , Ataque Isquémico Transitorio/complicaciones , Estudios de Cohortes , Estudios Prospectivos , Arterias Carótidas/diagnóstico por imagen , Estenosis Carotídea/complicaciones , Ultrasonografía/métodos , Placa Aterosclerótica/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/complicaciones , Factores de Riesgo , BiomarcadoresRESUMEN
Understanding terrestrial ecosystem dynamics requires a comprehensive examination of vegetation changes. Remote sensing technology has been established as an effective approach to reconstructing vegetation change history, investigating change properties, and evaluating the ecological effects. However, current remote sensing techniques are primarily focused on break detection but ignore long-term trend analysis. In this study, we proposed a novel framework based on a change detection algorithm and a trend analysis method that could integrate both short-term disturbance detection and long-term trends to comprehensively assess vegetation change. With this framework, we characterized the vegetation changes in Zhejiang Province from 1990 to 2020 using Landsat and landcover data. Benefiting from combining break detection and long-term trend analysis, the framework showcased its capability of capturing a variety of dynamics and trends of vegetation. The results show that the vegetation was browning in the plains while greening in the mountains, and the overall vegetation was gradually greening during the study period. By comparison, detected vegetation disturbances covered 57.71% of the province's land areas (accounting for 66.92% of the vegetated region) which were mainly distributed around the built-up areas, and most disturbances (94%) occurred in forest and cropland. There were two peak timings in the frequency of vegetation disturbances: around 2003 and around 2014, and the proportions of more than twice disturbances in a single location were low. The results illustrate that this framework is promising for the characterization of regional vegetation growth, including long-term trends and short-term features. The proposed framework enlightens a new direction for the continuous monitoring of vegetation dynamics.
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Ecosistema , Monitoreo del Ambiente , Factores de Tiempo , Monitoreo del Ambiente/métodos , Bosques , Tecnología de Sensores Remotos , Cambio Climático , ChinaRESUMEN
Infrared thermography is a widely utilized nondestructive testing technique in the field of artwork inspection. However, raw thermograms often suffer from problems, such as limited quantity and high background noise, due to limitations inherent in the acquisition equipment and experimental environment. To overcome these challenges, there is a growing interest in developing thermographic data enhancement methods. In this study, a defect inspection method for artwork based on principal component analysis is proposed, incorporating two distinct deep learning approaches for thermographic data enhancement: spectral normalized generative adversarial network (SNGAN) and convolutional autoencoder (CAE). The SNGAN strategy focuses on augmenting the thermal images, while the CAE strategy emphasizes enhancing their quality. Subsequently, principal component thermography (PCT) is employed to analyze the processed data and improve the detectability of defects. Comparing the results to using PCT alone, the integration of the SNGAN strategy led to a 1.08% enhancement in the signal-to-noise ratio, while the utilization of the CAE strategy resulted in an 8.73% improvement.
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The digitalization of information is crucial for the upgrading of the bayberry digital agriculture industry, while the low-cost information detection sensing equipment for bayberry are a bottleneck for the digital development of the industry. The existing rapid and non-destructive detection devices for fruit acidity and sugar content mainly use near-infrared and mid-infrared spectral characteristic for detection. These devices use expensive InGaAs sensor, which are difficult to promote and apply in the bayberry digital industry. This study is based on the high-spectral range of 454-998 nm in bayberry fruit to study the mechanism of fruit sugar and acidity content detection and to develop a portable bayberry fruit sugar and acidity detection device using Si-sensor in order to achieve low-cost quality parameter detection of bayberry fruit. The research results show that: Based on the hyperspectral of bayberry fruit, the sensitive wavelength for sugar content inversion is 610 nm, and the inversion accuracy (RMSE) is 1.399Brix; the sensitive wavelength for pH inversion is 570 nm, and the inversion accuracy (RMSE) is 0.1329. Based on the above spectroscopic detection mechanism and spectral dimension reduction methods, combined with low-cost Si-sensor (400-1000 nm), a low-cost non-destructive portable bayberry fruit sugar and acidity detection device has been developed, with detection accuracies of 94.74% and 97.14%, respectively. This bayberry fruit sugar and acidity detector provides a low-cost portable non-destructive quality detection instrument of bayberry, which is in line with the industrial group of low consumption in which the bayberry is mainly cultivated on a small scale, accelerating the digitalization process of the bayberry industry.
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Soybean is an important source of oil and vegetable protein and plays a key role in agricultural production and economy. A suitability evaluation of soybean cultivation is important for identifying potential soybean planting areas. Based on the raster data of soybean harvest ratio (FSHA) and climate-soil-topography-socio-economy environmental factors, we used MaxEnt to simulate the soybean planting suitability and potential distribution in China and the future trends of soybean cultivation under climate change. Three shared socio-economic paths (SSPs) that set up in the future climate section were considered, including SSP126 (sustainable path), SSP245 (intermediate path), and SSP585 (fossil fuel dominated development path). The result shows that the suitability of soybean cultivation was primarily influenced by elevation, precipitation of warmest quarter, capacity of the clay fraction, slope, portion of primary industry, topsoil gravel content, mean diurnal temperature range and accumulated temperature ≥10 °C. High-suitability and moderate-suitability area are respectively 26.51 Mha and 41.93 Mha in China. High-suitability areas for soybean are mainly concentrated in the Northeast Plain, the North China Plain and the northern parts of the middle and lower Yangtze River plain. There were many provinces with high soybean planting potential but low development degrees, including Hebei, Henan, Shandong, Tianjin, Jilin, Liaoning, Jiangsu, Hubei and Shaanxi. From 2021 to 2060, the total area highly and moderately suitable for soybean cultivation is projected to increase first and then decrease under both SSP126 and SSP245 scenarios. However, it shows a continued upward trend under SSP585, the rising part accounting for more than 10% in the base of historical data. Specifically, under SSP585, the suitability grade in most parts of Northeast China (eastern Inner Mongolia, northern Heilongjiang and western Jilin and Liaoning) will have a general promotion, opposite to the result under SSP126. Moreover, parts of southwest China (Yunnan, Chongqing, northern Guizhou and eastern Sichuan) may be more suitable for soybean cultivation in both scenarios. This study provides a practical reference for current and future soybean planting layout and relative countermeasures.
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Cambio Climático , Glycine max , China , Suelo , AgriculturaRESUMEN
Sleep deprivation (SD) is very common in modern society and regarded as a potential causal mechanism of several clinical disorders. Previous neuroimaging studies have explored the neural mechanisms of SD using magnetic resonance imaging (MRI) from static (comparing two MRI sessions [one after SD and one after resting wakefulness]) and dynamic (using repeated MRI during one night of SD) perspectives. Recent SD researches have focused on the dynamic functional brain organization during the resting-state scan. Our present study adopted a novel metric (temporal variability), which has been successfully applied to many clinical diseases, to examine the dynamic functional connectivity after SD in 55 normal young subjects. We found that sleep-deprived subjects showed increased regional-level temporal variability in large-scale brain regions, and decreased regional-level temporal variability in several thalamus subregions. After SD, participants exhibited enhanced intra-network temporal variability in the default mode network (DMN) and increased inter-network temporal variability in numerous subnetwork pairs. Furthermore, we found that the inter-network temporal variability between visual network and DMN was negative related with the slowest 10% respond speed (ß = -.42, p = 5.57 × 10-4 ) of the psychomotor vigilance test after SD following the stepwise regression analysis. In conclusion, our findings suggested that sleep-deprived subjects showed abnormal dynamic brain functional configuration, which provides new insights into the neural underpinnings of SD and contributes to our understanding of the pathophysiology of clinical disorders.
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Mapeo Encefálico , Privación de Sueño , Encéfalo/fisiología , Humanos , Imagen por Resonancia Magnética/métodos , Vías Nerviosas/fisiología , Descanso , Privación de Sueño/diagnóstico por imagenRESUMEN
BACKGROUND: Risk stratification of asymptomatic carotid plaque remains an issue in stroke prevention in clinical practice. PURPOSE: To investigate whether a multimodal ultrasound (MMU) model would help plaque risk stratification in patients with asymptomatic carotid stenosis. MATERIAL AND METHODS: A prospective study was conducted of symptomatic and asymptomatic patients with > 50% proximal internal carotid artery (ICA) stenosis. All patients underwent MMU examination. Multivariable regression analyses were performed to identify parameters associated with ischemic vascular events (IVE). These parameters were used to develop a scoring nomogram to assess the probability of IVE. We elaborated the diagnostic performance of the MMU nomogram using receiver operating characteristic (ROC) curves. RESULTS: From December 2018 to December 2019, 98 patients (75 men, mean age 67 ± 8 years) were included; 50 were symptomatic and 48 were asymptomatic. Multivariable regression analyses revealed that plaque surface morphology (PSM) (odds ratio [OR] 2.99, 95% confidence interval [CI] 1.26-7.12, P = 0.013), intraplaque neovascularization (IPN) grades (OR 3.23, 95% CI 1.77-5.89, P<0.001), and carotid stenosis degree (CSD) (OR 4.12, 95% CI 1.47-11.55, P = 0.007) were independently associated with IVE. For the nomogram, the area under the ROC curve was 0.85 (95% CI 0.77-0.92) and the Hosmer-Lemeshow test P value was 0.822. CONCLUSIONS: In patients with proximal ICA > 50%, PSM, IPN grades, and CSD were independent variables associated with IVE. The MMU nomogram provided favorable value to risk stratification of IVE. Future large-scale studies with long-term follow-up are needed to validate these findings.
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Enfermedades Asintomáticas , Estenosis Carotídea/diagnóstico por imagen , Imagen Multimodal , Placa Aterosclerótica/diagnóstico por imagen , Ultrasonografía Doppler en Color , Anciano , Arteria Carótida Interna/diagnóstico por imagen , Estenosis Carotídea/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/complicaciones , Estudios Prospectivos , Curva ROC , Análisis de Regresión , Medición de Riesgo , Accidente Cerebrovascular/prevención & controlRESUMEN
OBJECTIVES: To identify the ultrasonographic characteristics of primary squamous cell carcinoma of the thyroid (PSCCT), and to assess the value of the 2015 American Thyroid Association (ATA) guideline and 2017 American College of Radiology (ACR) Thyroid Imaging, Reporting and Data System (TI-RADS) in the evaluation of this disease. METHODS: Eight patients with 9 PSCCTs over a 20-year study period were enrolled. Ultrasonic characteristics including nodule echogenicity, composition, shape, margin, calcification, size, vascularity, and cervical lymphadenopathy were reviewed. All nodules were then evaluated by 2017 ACR TI-RADS and 2015 ATA guidelines. RESULTS: The average size of PSCCTs was 3.87 ± 1.41 cm. All PSCCTs were hypoechoic or very hypoechoic, solid nodules with intranodular vascularity. The average resistive index (RI) was 0.84 ± 0.18. Near half of PSCCTs (44.4%) demonstrated extrathyroidal extension. Taller-than-wide signs and cervical lymphadenopathy were observed in 33.3% of PSCCTs, and microcalcification was observed in 11.1% of them. All PSCCTs were classified as high suspicion patterns by 2015 ATA and recommended for fine-needle aspiration (FNA). Six PSCCTs (66.7%) were classified as grade 5 by 2017 ACR TI-RADS, while the remaining were grade 4. 88.9% of PSCCTs were recommended for FNA based on 2017 ACR TI-RADS. CONCLUSION: PSCCT has certain ultrasonic features, including relatively large, hypoechoic, or very hypoechoic solid nodules with intranodular vascularity and extrathyroidal extension. Both 2015 ATA and 2017 ACR TI-RADS could identify PSCCT as suspicious for malignancy.
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Carcinoma de Células Escamosas , Linfadenopatía , Neoplasias de la Tiroides , Nódulo Tiroideo , Carcinoma de Células Escamosas/diagnóstico por imagen , Humanos , Estudios Retrospectivos , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Ultrasonido , Ultrasonografía/métodos , Estados UnidosRESUMEN
The PROSPECT leaf optical radiative transfer models, including PROSPECT-MP, have addressed the contributions of multiple photosynthetic pigments (chlorophyll a and b, and carotenoids) to leaf optical properties, but photo-protective pigment (anthocyanins), another important indicator of vegetation physiological and ecological functions, has not been simultaneously combined within a leaf optical model. Here, we present a new calibration and validation of PROSPECT-MP+ that separates the contributions of multiple photosynthetic and photo-protective pigments to leaf spectrum in the 400-800 nm range using a new empirical dataset that contains multiple photosynthetic and photo-protective pigments (LOPEX_ZJU dataset). We first provide multiple distinct in vivo individual photosynthetic and photo-protective pigment absorption coefficients and leaf average refractive index of the leaf interior using the LOPEX_ZJU dataset. Then, we evaluate the capabilities of PROSPECT-MP+ for forward modelling of leaf directional hemispherical reflectance and transmittance spectra and for retrieval of pigment concentrations by model inversion. The main result of this study is that the absorption coefficients of chlorophyll a and b, carotenoids, and anthocyanins display the physical principles of absorption spectra. Moreover, the validation result of this study demonstrates the potential of PROSPECT-MP+ for improving capabilities in remote sensing of leaf photosynthetic pigments (chlorophyll a and b, and carotenoids) and photo-protective pigment (anthocyanins).
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Antocianinas , Carotenoides , Clorofila , Clorofila A , Hojas de la Planta/fisiologíaRESUMEN
AIMS: To examine relationships between psychological capital, work engagement and organisational citizenship behaviour among nurses. BACKGROUND: Psychological capital, work engagement and organisational citizenship behaviour are all positive variables associated with work. Clarifying the relationship between the variables can help nursing managers implement tailored and effective intervention strategies to improve individual and organisational performance and quality of care. DESIGN: A quantitative cross-sectional study was designed. METHODS: The study was carried out from June 2021 to September 2021 in Sichuan Province, China. A total of 606 nurses working at six tertiary hospitals were selected with convenience sampling. Participants were investigated using demographic, work-related information questionnaire, Psychological Capital Questionnaire, Utrecht Work Engagement Scale and Organizational Citizenship Behavior Questionnaire. RESULTS: The scores of psychological capital, work engagement and organisational citizenship behaviour were 102.56 ± 15.47, 67.96 ± 21.71 and 101.57 ± 11.57, respectively. The multiple linear regression model explained 7.3% of the total variance in organisational citizenship behaviour related to demographic and work-related factors. There was a significant positive correlation between psychological capital, work engagement and nurses' organisational citizenship behaviour. Additionally, structural equation modeling showed that work engagement mediated the relationship between psychological capital and organisational citizenship behaviour with the partial mediating effect of 0.093. The final model explained 28% of organisational citizenship behaviour. CONCLUSION: Our results suggest that both psychological capital and work engagement are facilitators for organisational citizenship behaviour in nurses. Managers can increase nurses' organisational citizenship behaviour through developing psychological capital and improving the work engagement. IMPLICATIONS FOR NURSING MANAGEMENT: This study indicates that both psychological capital and work engagement are protective factors of organisational citizenship behaviour, which provide proof for optimizing human resources management from a positive psychology perspective. Our finding can help managers correctly understand the mechanism of the relationship among work engagement, psychological capital and organisational citizenship behaviour and adopt effective intervention strategies to promote nurses' organisational citizenship behaviour.
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Enfermeras Administradoras , Enfermeras y Enfermeros , Personal de Enfermería en Hospital , Ciudadanía , Estudios Transversales , Humanos , Satisfacción en el Trabajo , Personal de Enfermería en Hospital/psicología , Cultura Organizacional , Encuestas y Cuestionarios , Compromiso LaboralRESUMEN
The aberrant static functional connectivity of brain network has been widely investigated in patients with functional constipation (FCon). However, the dynamics of brain functional connectivity in FCon patients remained unknown. This study aimed to detect the brain dynamics of functional connectivity states and network topological organizations of FCon patients and investigate the correlations of the aberrant brain dynamics with symptom severity. Eighty-three FCon patients and 80 healthy subjects (HS) were included in data analysis. The spatial group independent component analysis, sliding-window approach, k-means clustering, and graph-theoretic analysis were applied to investigate the dynamic temporal properties and coupling patterns of functional connectivity states, as well as the time-variation of network topological organizations in FCon patients. Four reoccurring functional connectivity states were identified in k-means clustering analysis. Compared to HS, FCon patients manifested the lower occurrence rate and mean dwell time in the state with a complex connection between default mode network and cognitive control network, as well as the aberrant anterior insula-cortical coupling patterns in this state, which were significantly correlated with the symptom severity. The graph-theoretic analysis demonstrated that FCon patients had higher sample entropy at the nodal efficiency of anterior insula than HS. The current findings provided dynamic perspectives for understanding the brain connectome of FCon and laid the foundation for the potential treatment of FCon based on brain connectomics.
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Corteza Cerebral/fisiopatología , Conectoma , Estreñimiento/fisiopatología , Red Nerviosa/fisiopatología , Adulto , Corteza Cerebral/diagnóstico por imagen , Estreñimiento/diagnóstico por imagen , Femenino , Humanos , Corteza Insular/diagnóstico por imagen , Corteza Insular/fisiopatología , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Adulto JovenRESUMEN
Secondary metabolites produced in glandular trichomes of tomato are involved in interactions with herbivores. In cultivated tomato (Solanum lycopersicum) glandular trichomes accumulate a blend of abundant monoterpenes and smaller amounts of a few sesquiterpenes. These mono- and sesquiterpenes are synthesized by three terpene synthases, TPS20 as well as TPS9 and TPS12, respectively. To study effects of these terpenes on performance and choice behavior of potato aphid (Macrosiphum euphorbiae), we utilized two tomato trichome mutants, hairless and odorless-2, that are differently affected in mono- and sesquiterpene production. Non-choice assays demonstrated that longevity and fecundity of M. euphorbiae were increased when kept on the trichome mutants. A principal component analysis of these aphid performance parameters and terpene production in the trichome mutants indicated that longevity and fecundity of M. euphorbiae were negatively correlated with production of the TPS12-derived sesquiterpenes ß-caryophyllene and α-humulene. While we had previously shown that addition of pure ß-caryophyllene/α-humulene to an artificial feeding diet affected M. euphorbiae apterae survivorship and feeding behavior, no such effects were observed here upon addition of a mixture of pure TPS20-derived monoterpenes. In olfactometer assays M. euphorbiae alates displayed differential choice behaviors towards the hairless and odorless-2 mutants suggesting a role of TPS20-derived monoterpenes in aphid attraction, which was further confirmed using a mixture of pure monoterpenes. Our analyses revealed contrasting roles of glandular trichome-derived terpenes in S. lycopersicum. While TPS12-derived sesquiterpenes contribute to host plant resistance against M. euphorbiae, TPS20-derived monoterpenes appear to be exploited as cue for host plant orientation by aphids.
Asunto(s)
Áfidos/fisiología , Monoterpenos/metabolismo , Sesquiterpenos Policíclicos/metabolismo , Solanum lycopersicum/metabolismo , Tricomas/metabolismo , Animales , Fertilidad , Longevidad , Solanum lycopersicum/genética , Sesquiterpenos Monocíclicos/metabolismo , OlfatometríaRESUMEN
A supercapacitor electrode with high capacitance is mainly based on the careful design of nanostructures and the intelligent hybridization of custom active materials. Herein, we designed 3D core-shell nanoforest arrays with hierarchical structure which are directly grown on carbon cloth using a two-step bracket-hydrothermal method and electrodeposition process. Due to the advantages of large specific surface area, abundant pores and active sites, the structure of Mo-Co-Ni(nanotube)@Ni-Co(nanosheet) arrays can promote electrolyte penetration and ions diffusion, further improving the electrochemical performance. The 3D core-shell nanoforest arrays electrode shows outstanding electrochemical performance: a superb areal capacitance of 9.81 F cm-2 (1998.0 F g-1) at the current densities of 1 mA cm-2, as well as long cycle stability (after 3000 cycles maintains 85.4% of the highest capacitance value). This work may provide a promising method for design of flexible supercapacitor electrode materials.
RESUMEN
We present the design of single-mode fibers for two-stage higher-order soliton compression at 2 µm wavelength and achieve high-degree pulse compression in cascaded single-mode fibers. The compression performance for the initial input pulse width from 1 to 50 ps is also investigated. For the initial third-order soliton of 10 ps, a compression factor of 75.7 has been achieved, and the pedestal energy is only 46.66%.