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SignificanceThe detection of low-abundance molecular biomarkers is key to the liquid-biopsy-based disease diagnosis. Existing methods are limited by the affinity and specificity of recognition probes and the mass transportation of analyte molecules onto the sensor surfaces, resulting in insufficient sensitivity and long assay time. This work establishes a rapid and ultrasensitive approach by actively tuning binding kinetics and accelerating the mass transportation via nanoparticle micromanipulations. This is significant because it permits extremely sensitive measurements within clinically acceptable assay time. It is incubation-free, washing-free, and compatible with low- and high-affinity probes.
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Imagen Individual de Molécula/métodos , Sitios de Unión , Biomarcadores/metabolismo , Cinética , Límite de Detección , TermodinámicaRESUMEN
The unique capability of surface plasmon resonance microscopy (SPRM) in single nanoparticle analysis has found use in various chemical and biological applications. While SPRM offers exceptional sensitivity, the statistical analysis of numerous nanoparticles has been extremely laborious and time-consuming. Herein, we presented an image processing software package for nanoparticle analysis in SPRM, which is empowered by a deep learning algorithm. This package enabled fully automated nanoparticle identification, digital counting, three-dimensional tracking of particle locations, and quantification of dwell time and Brownian motion properties. With a built-in image filtering process to improve the contrast, robust identification and analysis have been achieved from SPRM images of low refractive index nanoparticles. This software tool would largely promote the translation of SPRM technology into the digital sensing platform for high throughput sample screening.
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Nanopartículas , Resonancia por Plasmón de Superficie , Algoritmos , Microscopía , Movimiento (Física)RESUMEN
Surface plasmon resonance microscopy (SPRM) has been widely used as a sensitive imaging platform for chemical and biological analysis. The SPRM system inevitably suffers from focus inhomogeneity and drifts, especially in long-term recordings, leading to distorted images and inaccurate quantification. Traditional focus correction approaches require additional optical parts to detect and adjust focal conditions. Herein, we propose a deep-learning-based image processing method to gain autofocused SPRM images, without increasing the complexity of the optical systems. We trained a generative adversarial network (GAN) model with thousands of SPRM images of nanoparticles acquired at different focal distances. The trained model was able to directly generate focused SPRM images from single-shot defocused images, with no prior knowledge of the focus conditions during recording. Experiments using Au nanoparticles show that this method is effective in both static and time-lapse monitoring. The proposed autofocus technique thus provides an approach for improving the consistency among SPRM studies and for long-term monitoring.
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The grass carp reovirus (GCRV) has been shown to cause lethal infections in the grass carp Ctenopharyngodon idella (C. idella). In order to investigate the immune response to GCRV infection, the full-length cDNA sequences of coagulation factor VIII (CiFVIII) and plasminogen (CiPLG) from C. idella were cloned and their involvement in the immune response was studied. The immunity factor levels in C. idella with different GCRV resistances were also analyzed. The full-length 2478 bp cDNA of CiFVIII contained an open reading frame of 1965 bp and encoded a putative polypeptide of 654 amino acid residues. The full-length 2907 bp cDNA of CiPLG contained an open reading frame of 2133 bp and encoded a putative polypeptide of 710 amino acid residues. CiFVIII was closely clustered with that of Clupea harengus. CiPLG was first clustered with those of Cyprinus carpio and Danio rerio. CiFVIII transcripts were most abundant in the liver and least in the skin. The highest expression level of CiPLG was observed in liver and the lowest in muscle. Expression levels of CiFVIII in gill, head kidney and spleen, and expression levels of CiPLG in gill, intestine and liver all reached the maximum at 72â¯h post GCRV infection. In spleen, expression levels of CiFVIII and CiPLG were significantly positively correlated. The activities of T-AOC, LSZ and IgM in Râ were significantly higher than those in Oâ. Likewise, T-AOC and LSZ activities in F1 were significantly higher than f1 individuals (Pâ¯<â¯0.01). These results indicated that CiFVIII and CiPLG may play important roles in the immune response to GCRV infection. In addition, antioxidant ability and serum immune factor activity may confer a different viral resistance to C. idella.
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Carpas/genética , Carpas/inmunología , Enfermedades de los Peces/inmunología , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , Factor VIII/química , Factor VIII/genética , Factor VIII/inmunología , Proteínas de Peces/química , Perfilación de la Expresión Génica/veterinaria , Filogenia , Plasminógeno/química , Plasminógeno/genética , Plasminógeno/inmunología , Reoviridae/fisiología , Infecciones por Reoviridae/inmunología , Alineación de Secuencia/veterinariaRESUMEN
The barbel chub (Squaliobarbus curriculus) is a kind of small size commercial fish species that is widely spread in Asia and has shown significant resistance to disease. In this study, the full-length cDNA sequences of Toll-like receptor (TLR) 7 and 8 from S. curriculus, designated as ScTLR7 and ScTLR8, were cloned, and their differences in the structure and the responses to the grass carp (GCRV) infection and lipopolysaccharide stimulation were investigated. The full-length 3715 base pair (bp) cDNA of ScTLR7 contained a complete open reading frame of 3162 bp and encoded a putative polypeptide of 1053 amino acid residues. The full-length 4624 base pair (bp) cDNA of ScTLR8 contained a complete open reading frame of 3072 bp and encoded a putative polypeptide of 1023 amino acid residues. ScTLR7 and ScTLR8 consisted of N-terminal signal peptide, leucine-rich repeats (LRRs), and Toll/IL-1 Receptors domain. LRR motifs of ScTLR7 and ScTLR8 bend into horseshoe-like solenoid structure, while the number of LRRs between the two genes is different. Phylogenetic analysis showed that both the ScTLR7 and ScTLR8 were closely clustered with Ctenopharyngodon idellus and Megalobrama amblycephala. Quantitative real-time polymerase chain reaction analysis showed that the expression levels of ScTLR7 in S. curriculus were most abundant in the brain followed by the spleen and heart, and the lowest in the intestine. The highest expression level of ScTLR8 was observed in spleen and the lowest in the liver. After LPS stimulation, the relative expression levels of both ScTLR7 and ScTLR8 exhibited an overall trend of up-regulation. The expression levels of type I-IFN showed an overall trend of down-regulation at time points of 12, 24, 72 and 168â¯h compared to that of 6â¯h after LPS stimulation. Compared to 6â¯h post GCRV infection, the transcription level of ScTLR7 was up-regulated from 12 to 168â¯h, and transcription levels of ScTLR8, MyD88, and type I-IFN were firstly up-regulated from 12 to 72â¯h, and then down-regulated from 72 to 168â¯h. Correlation analysis showed that expression level of ScTLR7 in the spleen was significantly positively correlated with that of MyD88 (Pearson correlation coefficient: 0.909, P: 0.033), and a significantly positive correlation was also observed between expression levels of MyD88 and type I IFN (Pearson correlation coefficient: 0.962, P: 0.009), after GCRV stimulation. These results indicate that ScTLR7 and ScTLR8 may play important roles in the responses to the grass carp (GCRV) infection and lipopolysaccharide stimulation and trigger different downstream immune signal pathways.
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Cyprinidae/inmunología , Proteínas de Peces/inmunología , Receptor Toll-Like 7/inmunología , Receptor Toll-Like 8/inmunología , Animales , Cyprinidae/genética , Enfermedades de los Peces/inmunología , Proteínas de Peces/genética , Lipopolisacáridos/farmacología , Reoviridae , Infecciones por Reoviridae/inmunología , Infecciones por Reoviridae/veterinaria , Receptor Toll-Like 7/genética , Receptor Toll-Like 8/genéticaRESUMEN
Hairiness is a concept describing the amount of hairy fibers (hairs) protruding from a yarn core in different spatial orientations and shapes. Most image-based hairiness assessment methods measure hairs by projecting a yarn on a 2D image plane, which suffers from two major problems: 1) not detecting defocused hairs (fuzzy hairs) when hairs are out of the field of view of the imaging system and 2) miscalculating real lengths of spatially curved hairs. The objective of this research was to develop a new image-based hairiness measurement method to mitigate these problems. The proposed method included two tasks: yarn image segmentation and hairiness assessment. The first task was to improve the detection rate of fuzzy hairs with a hybrid algorithm combining double homomorphic filtering and region-growing algorithms. The second task was to establish a width-depth mapping model for defocused hairs to compensate measurable lengths of defocused hairs based on their width information. The experiment results demonstrated that the proposed segmentation algorithm can detect fuzzy hairs usually missed by the previously used algorithm, and can produce more accurate hair length measurements than the previous algorithm when compared to the corresponding manual measurements, which were considered as the gold standard in this study.
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Business simulation games (BSGs) have been widely used in entrepreneurship education with positive effects. However, there are still some deficiencies in the BSGs, such as limited guidance, low uncertainty and limited simulation environment, which make it impossible to exert the maximum effect. Artificial intelligence (AI) can solve the above shortcomings. The combination of AI and BSGs is the possible development direction of BSGs. But how to effectively combine BSGs with AI is still an open question. Using a quasi-experimental design, this study uses fuzzy-set qualitative comparative analysis to analyze how participants' entrepreneurial attitude changes in BSGs. The results show that BSGs can effectively improve entrepreneurial attitude, and there are four types of promotion configurations. These four configurations consist of five antecedent conditions. According to the above conclusions, AI can improve entrepreneurial attitude in BSGs in various ways, such as simulating competitors, providing targeted feedback for failures, and improving game experience. The contribution of this paper is to highlight the possibility of combining AI with BSGs, and to provide suggestions on how AI can intervene in BSGs.
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We analyzed, for the first time, the major components and biological properties of the venom of Vespa bicolor, a wasp from South China. Using HPLC and SDS-PAGE, combined with LC-MS/MS, MALDI-TOF-MS, and NMR data to analyze V. bicolor venom (VBV), we found that VBV contains three proteins (hyaluronidase A, phospholipase A1 (two isoforms), and antigen 5 protein) with allergenic activity, two unreported proteins (proteins 5 and 6), and two active substances with large quantities (mastoparan-like peptide 12a (Vb-MLP 12a), and 5-hydroxytryptamine (5-HT)). In addition, the antimicrobial activity of VBV was determined, and results showed that it had a significant effect against anaerobic bacteria. The minimum inhibitory concentration and minimum bactericidal concentration for Propionibacterium acnes were 12.5 µg/mL. Unsurprisingly, VBV had strong antioxidant activity because of the abundance of 5-HT. Contrary to other Vespa venom, VBV showed significant anti-inflammatory activity, even at low concentrations (1 µg/mL), and we found that Vb-MLP 12a showed pro-inflammatory activity by promoting the proliferation of RAW 264.7 cells. Cytotoxicity studies showed that VBV had similar antiproliferative effects against all tested tumor cell lines (HepG2, Hela, MCF-7, A549, and SASJ-1), with HepG2 being the most susceptible. Overall, this study on VBV has high clinical importance and promotes the development of Vespa bicolor resources.
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Proteínas de Insectos , Venenos de Avispas , Avispas/química , Células A549 , Animales , China , Células HeLa , Células Hep G2 , Humanos , Proteínas de Insectos/química , Proteínas de Insectos/farmacología , Células MCF-7 , Pruebas de Sensibilidad Microbiana , Venenos de Avispas/química , Venenos de Avispas/farmacologíaRESUMEN
Limb regeneration is a fascinating and medically interesting trait that has been well preserved in arthropod lineages, particularly in crustaceans. However, the molecular mechanisms underlying arthropod limb regeneration remain largely elusive. The Chinese mitten crab Eriocheir sinensis shows strong regenerative capacity, a trait that has likely allowed it to become a worldwide invasive species. Here, we report a chromosome-level genome of E. sinensis as well as large-scale transcriptome data during the limb regeneration process. Our results reveal that arthropod-specific genes involved in signal transduction, immune response, histone methylation, and cuticle development all play fundamental roles during the regeneration process. Particularly, Innexin2-mediated signal transduction likely facilitates the early stage of the regeneration process, while an effective crustacean-specific prophenoloxidase system (ProPo-AS) plays crucial roles in the initial immune response. Collectively, our findings uncover novel genetic pathways pertaining to arthropod limb regeneration and provide valuable resources for studies on regeneration from a comparative perspective.
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Histonas , Transcriptoma , China , Genoma , Histonas/genética , Regeneración/genéticaRESUMEN
Aiming at spectral detection of apple fluorescence canopy, the present paper carried out spectral detection tests under different weather conditions, different detection times, and different detection heights and angles to apple canopy in the two years of 2008 and 2009, so as to analyze impacts of these factors on apple canopy spectral characteristics and explore standardized spectral detection methods for apple fluorescence canopy. The results indicated the regularity in spectral reflectance of apple fluorescence canopy to a certain degree under different conditions, especially in the 760-1 350 nm near-infrared bands. The authors found that canopy spectral reflectance declined along with the decrease in sunshine and it is appropriate to detect canopy spectrum in sunny days with few clouds. In addition, spectral reflectance tended to be stable when the wind scale was below grade 2. The discrepancy of canopy spectra is small during the time period from 10:00 to 15:00 of a day compared to that of other times. For maintaining stable spectral curves, the height of detector to apple canopy needed to be adjusted to cover the whole canopy within the field of view according to detection angle of the detector. The vertical or approximately vertical detection was the best for canopy spectral reflectance acquisition. The standardization of technical methods of spectral detection for apple fluorescence canopy was proposed accordingly, which provided theoretical references for spectral detection and information extraction of apple tree canopy.
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Malus , Espectrometría de Fluorescencia/normas , Luz SolarRESUMEN
To elucidate the immunity-protecting role of the interferon-ß promoter stimulator-1 (ScIPS-1) in barbel chub Squaliobarbus curriculus, the full-length cDNA of ScIPS-1 was cloned and expression levels in response to stimulation were investigated. In addition, the function of ScIPS-1 and its domains were analyzed. The full-length cDNA of ScIPS-1 is 2524 bp and encodes 601 aa. The N-terminal caspase activation and recruitment domain, central proline-rich domain, C-terminal transmembrane domain, C2HC-zinc finger, and Cwf21 domains were identified. The mRNA level of ScIPS-1 was the highest in the kidney, whereas the highest protein level was observed in the liver. The ScIPS-1 expressions were significantly up-regulated after lipopolysaccharide and poly I:C treatment. The ScIPS-1 protein level was up-regulated at 12 h in the head kidney and was up-regulated at 12 h and then down-regulated from 12 to 48 h in the liver after grass carp reovirus (GCRV) infection. The CiIFN and CiMx transcription levels were significantly enhanced in pEGFP-C1-IPS-1 and pcDNA3.1-ΔCwf21 overexpressing cells after GCRV infection. The results indicate that ScIPS-1 may function in the immune response against pathogens and provide a basis for achieving resistance to diseases in fish breeding.
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Proteínas Adaptadoras Transductoras de Señales/genética , Cyprinidae/inmunología , Proteínas de Peces/genética , Riñón Cefálico/metabolismo , Infecciones por Reoviridae/inmunología , Reoviridae/fisiología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Células Cultivadas , Clonación Molecular , Proteínas de Peces/metabolismo , Riñón Cefálico/inmunología , Humanos , Inmunidad Innata , Interferón beta/genética , Lipopolisacáridos/inmunología , Alineación de Secuencia , Regulación hacia ArribaRESUMEN
Activin receptor IIB (ActRIIB) is a serine/threonine-kinase receptor binding with transforming growth factor-ß (TGF-ß) superfamily ligands to participate in the regulation of muscle mass in vertebrates. However, its structure and function in crustaceans remain unknown. In this study, the ActRIIB gene in Eriocheir sinensis (Es-ActRIIB) was cloned and obtained with a 1,683 bp open reading frame, which contains the characteristic domains of TGF-ß type II receptor superfamily, encoding 560 amino acids. The mRNA expression of Es-ActRIIB was the highest in hepatopancreas and the lowest in muscle at each molting stage. After injection of Es-ActRIIB double-stranded RNA during one molting cycle, the RNA interference (RNAi) group showed higher weight gain rate, higher specific growth rate, and lower hepatopancreas index compared with the control group. Meanwhile, the RNAi group displayed a significantly increased content of hydrolytic amino acid in both hepatopancreas and muscle. The RNAi group also displayed slightly higher contents of saturated fatty acid and monounsaturated fatty acid but significantly decreased levels of polyunsaturated fatty acid compared with the control group. After RNAi on Es-ActRIIB, the mRNA expressions of five ActRIIB signaling pathway genes showed that ActRI and forkhead box O (FoxO) were downregulated in hepatopancreas and muscle, but no significant expression differences were found in small mother against decapentaplegic (SMAD) 3, SMAD4 and mammalian target of rapamycin. The mRNA expression s of three lipid metabolism-related genes (carnitine palmitoyltransferase 1ß (CPT1ß), fatty acid synthase, and fatty acid elongation) were significantly downregulated in both hepatopancreas and muscle with the exception of CPT1ß in muscles. These results indicate that ActRIIB is a functionally conservative negative regulator in growth mass, and protein and lipid metabolism could be affected by inhibiting ActRIIB signaling in crustacean.
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Growth hormone (ScGH) and growth hormone receptor (ScGHR) genes from the barbel chub (Squaliobarbus curriculus), in addition to their cDNAs, were cloned. The associations between their mRNA expression levels and growth-related traits were analysed, and the differences in the levels of expression of growth regulation-related genes between the largest and smallest individuals were compared. The full-length 1182-bp cDNA of ScGH contained a 633-bp open reading frame (ORF), and the length of the gene had 2492 bp. The full-length 2825-bp cDNA of ScGHRa contained a 1818-bp ORF, and the gene had 6970 bp. The full-length 2822-bp cDNA of ScGHRb contained a 1737-bp ORF, and the gene had 8149 bp. Quantitative real-time PCR revealed that ScGH was only expressed in the pituitary. ScGHRa was expressed predominantly in muscle, and the expression level of ScGHRb was the highest in the liver. The ScGHRa mRNA levels in the muscle were significantly negatively correlated with the caudal peduncle length. However, no correlation between growth-related traits and ScGH and ScGHRb expression levels were found. Pituitary ScGH, liver GHRb and liver insulin-like growth factor I (igf-1) expression levels were significantly higher in the largest individuals than those in the smallest S. curriculus individuals. Contrarily, the largest individuals had significantly lower expression levels of muscle igf-1 and liver myog than the smallest individuals. Overall, our results provide novel molecular information for growth-regulation study of S. curriculus.
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Cyprinidae/genética , Proteínas de Peces/genética , Regulación de la Expresión Génica/genética , Hormona del Crecimiento/genética , Receptores de Somatotropina/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , Cyprinidae/crecimiento & desarrollo , Cyprinidae/metabolismo , ADN Complementario/genética , Proteínas de Peces/metabolismo , Hormona del Crecimiento/química , Hormona del Crecimiento/metabolismo , Sistemas de Lectura Abierta , Especificidad de Órganos , Filogenia , ARN Mensajero/metabolismo , Receptores de Somatotropina/química , Receptores de Somatotropina/metabolismoRESUMEN
OBJECTIVE: The objective of this study was to quantitatively measure the three-dimensional (3D) structure of the vocal folds in normal subjects and in patients with different types of cricoarytenoid dislocation. We will analyze differences in parameters between the groups and also determine if any morphologic parameters possess utility in distinguishing the type and the degree of cricoarytenoid dislocation. STUDY DESIGN: This retrospective study was conducted using university hospital data. METHODS: Subjects' larynges were scanned using dual-source computed tomography (CT). The normal subjects were divided into deep-inhalation and phonation groups, and patients with cricoarytenoid joint dislocation were divided into anterior-dislocation and posterior-dislocation groups. Membranous vocal fold length and width were measured directly on the thin-section CT images. Vocal fold and airway 3D models were constructed using Mimics software and used in combination to measure vocal fold thickness, subglottal convergence angle, and oblique angle of the vocal folds. RESULTS: The phonation group displayed a greater vocal fold width, greater oblique angle, thinner vocal folds, and a smaller subglottal convergence angle than those of the deep-inhalation group (P < 0.05). The anterior-dislocation group displayed a smaller oblique angle and subglottal convergence angle than the posterior-dislocation group (P < 0.05). CONCLUSIONS: The 3D structure of the vocal folds during deep inhalation and phonation can be accurately measured using dual-source CT and laryngeal 3D reconstruction. As the anterior-dislocation group yielded negative values for the oblique angle and the posterior-dislocation group yielded positive values, the oblique angle of the vocal folds may possess utility for distinguishing the type and for quantitatively determining the degree of cricoarytenoid dislocation.
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Cartílago Aritenoides/diagnóstico por imagen , Cartílago Cricoides/diagnóstico por imagen , Imagenología Tridimensional , Luxaciones Articulares/diagnóstico por imagen , Articulaciones/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Pliegues Vocales/diagnóstico por imagen , Adulto , Cartílago Aritenoides/fisiopatología , Cartílago Cricoides/fisiopatología , Femenino , Humanos , Inhalación , Luxaciones Articulares/fisiopatología , Articulaciones/fisiopatología , Masculino , Persona de Mediana Edad , Modelación Específica para el Paciente , Fonación , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Pliegues Vocales/fisiopatologíaRESUMEN
OBJECTIVE: This study aimed to explore subglottal convergence angle measurement. We hypothesize that the angle will change with glottis closure condition. Changes to the angle may alter vocal fold stress distribution, which could result in vocal fold pathologies. METHODS: Three vocal fold positions were evaluated by the degree of glottal closure and divided into three groups. Neck computed tomographic images of the subjects were gathered, and three-dimensional (3D) models of the vocal folds and the airway were reconstructed using Mimics software, through which the subglottal convergence angle was measured. Using one-way factor analysis of variance, we compared the angle among three groups. We explored the effect of the angle on vibration based on the material oblique section stress analysis. RESULTS: The subglottal convergence angle was effectively measured from 3D models. The angle changed with degree of glottal closure, with statistically significant differences among the three groups (P < 0.01). Changes to the angle alter subglottal stress distribution in the subglottal shear or normal direction by the material oblique section stress analysis theory. Larger subglottal convergence angle might reduce subglottal pressure in the shear direction below the vocal folds, which would make vibration and vocal fold mucosal wave generation more difficult. CONCLUSION: 3D model generation from computed tomographic data is an effective method of measuring the subglottal convergence angle, which changes with the degree of glottis closure, and may affect subglottal pressure distribution in the subglottal shear or normal direction and influence vocal fold vibration.
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Glotis/diagnóstico por imagen , Modelación Específica para el Paciente , Fonación , Tomografía Computarizada por Rayos X/métodos , Parálisis de los Pliegues Vocales/diagnóstico por imagen , Pliegues Vocales/diagnóstico por imagen , Calidad de la Voz , Adulto , Fenómenos Biomecánicos , Estudios de Casos y Controles , Femenino , Glotis/fisiopatología , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Modelos Anatómicos , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Programas Informáticos , Estrés Mecánico , Vibración , Parálisis de los Pliegues Vocales/fisiopatología , Pliegues Vocales/fisiopatologíaRESUMEN
R&D professionals are the impetus behind technological innovation, and their competitiveness and capability drive the growth of a company. However, high-tech industries have a chronic shortage of such indispensable professionals. Accordingly, reducing R&D personnel turnover has become a major human resource management challenge facing innovative companies. This study combined importance-performance analysis (IPA) with the decision-making trial and evaluation laboratory (DEMATEL) method to propose an IPA-DEMATEL model. Establishing this model involved three steps. First, an IPA was conducted to measure the importance of and satisfaction gained from job satisfaction criteria. Second, the DEMATEL method was used to determine the causal relationships of and interactive influence among the criteria. Third, a criteria model was constructed to evaluate job satisfaction of high-tech R&D personnel. On the basis of the findings, managerial suggestions are proposed.
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Industrias/estadística & datos numéricos , Satisfacción en el Trabajo , Modelos Estadísticos , Tecnología , Humanos , Industrias/economía , Investigación/economía , Investigación/estadística & datos numéricos , Encuestas y CuestionariosRESUMEN
Branches from three transgenic poplar lines and their wild type line 107 were used to study the effect of lignocellulosic composition and structure on the production of glucose and ethanol. Experimental results showed that the transgenic line 18-1 had the high cellulose content and amorphous fibril structure. After poplar meals were pretreated with 10% NaOH and a mixture of hydrogen peroxide and acetic acid, their lateral order index decreased significantly. The highest glucose yield in enzymatic hydrolysis and ethanol yield from the substrate of 18-1 was much higher than that from feedstock of 107 by 192.7% and 108.7%, respectively. Scanning electron microscopy images confirmed that lignocellulose from the 18-1 could be destroyed by chemicals more easily than those from other lines. These results demonstrated that changing lignocellulose structure could be more effective on improving the digestibility and enzymatic hydrolysis of poplar biomass than increasing the cellulose content in biomass.
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Biocombustibles , Biotecnología/métodos , Etanol/metabolismo , Lignina/química , Populus/metabolismo , Biomasa , Carbohidratos/biosíntesis , Celulasa/metabolismo , Cristalización , Fermentación , Genotipo , Glucosa/metabolismo , Hidrólisis , Lignina/ultraestructura , Populus/genética , Populus/ultraestructuraRESUMEN
AIMS: To study atrial tachycardia-induced electrical remodeling in a canine model of sinus node dysfunction (SND). MATERIALS AND METHODS: A canine model of SND was established by contacting a cotton patch with 20% formaldehyde on the sinus node. Atrial effective refractory period (ERP), ERP dispersion, and inducibility of atrial fibrillation (AF) were recorded at multiple sites in the atrium, before and after SND induction as well as after rapid atrial pacing. The recovery of atrial ERP in the left and right atrium (LA and RA) after cessation of atrial pacing was also recorded. RESULTS: Compared with baseline, the atrial ERPs were shortened after SND (P<0.05). After rapid atrial stimulation, the atrial ERPs were further decreased significantly (P<0.05), and the dispersion of atrial ERPs measured at different pacing cycle lengths (PCLs) showed significant variation. Seven sites were used to induce AF in each dog (56 sites in 8 dogs). The average duration and inducibility of AF after SND was increased compared with baseline (16.5±4.7 vs 2.3±1.2 s and 12/56 vs 4/56 sites, P<0.05). After rapid atrial stimulation, the average duration and inducibility of AF were further increased (16.5±4.7 vs 33.6±16.1 s and 12/56 vs 25/56 sites, P<0.05). The recovery of atrial ERP in LA was significantly delayed compared to the RA. CONCLUSION: SND induces atrial electrical remodeling which is further aggravated by atrial tachycardia. Therefore, SND creates an electrophysiological substrate that facilitates AF initiation and perpetuation.
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Fibrilación Atrial/fisiopatología , Modelos Animales de Enfermedad , Electrocardiografía , Síndrome del Seno Enfermo/fisiopatología , Animales , Fibrilación Atrial/complicaciones , Perros , Electrocardiografía/métodos , Síndrome del Seno Enfermo/complicaciones , Taquicardia Atrial Ectópica/complicaciones , Taquicardia Atrial Ectópica/fisiopatologíaRESUMEN
Detached leaf sections (2×2cm2) from transgenic poplar line 18-1 and its wild type (WT) (Populus× euramericana 'Neva') were used to test their salt tolerance and gene expression under controlled environment conditions. The sections from line 18-1 displayed better tolerance to NaCl stress, indicated by high chlorophyll retention and K+ content but low relative electrolyte leakage (REL). Transient overexpression of NTHK1 (Nicotiana tabacum histidine kinase 1) and V-H+-PPase was found in the detached young leaves from line 18-1 after they had been stressed for a few minutes. The activities of vacuolar-type H+-ATPase and H+-PPase in line 18-1 were boosted initially and then decreased to normal level as in unstressed leaves. After sections were stressed for 10 days, the maximal Na+ concentration in line 18-1 was much higher than that in the WT. The higher capacity for Na+ accumulation in line 18-1 may be due to stable Na+ sequestration into the vacuoles. Osmotic stress imposed little effect on REL and chlorophyll content of the sections. The capacity of detached leaf sections in NaCl solution to tolerate stress and to accumulate Na+ may be useful for identifying genotypes with good salt tolerance in poplar and other plants.
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The aim of the present study was to evaluate the antifungal activity of fatty acids against phytopathogenic fungi. Two pot experiments were conducted by mixing palmitic and oleic acids in the soil in which poor plant growth was observed. In addition, the antifungal activities of nine fatty acids (butyric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, and linoleic acid) against four phytopathogenic fungi: Alternaria solani, Colletotrichum lagenarium, Fusarium oxysporum f. sp. Cucumerinum, and Fusarium oxysporum f. sp. lycopersici, were assessed by measuring mycelial growth and spore germination via Petri dish assay. The results of the pot experiments showed that the mixture of palmitic and oleic acids enhanced the growth of the seedlings of continuous-tomato and continuous-cucumber. Except for oleic acid, in the Petri dish assay, the fatty acids tested were observed to inhibit the mycelial growth of one or more tested fungi. In addition to the suppression of mycelial growth, butyric acid, caproic acid, caprylic acid, capric acid, lauric acid, and palmitic acid showed an inhibitory effect against spore germination and the extent of inhibition varied with both the type of fatty acids, and the fungi. In particular, capric acid displayed strong inhibitory effect against C. lagenarium on the mycelial growth and spore germination. The saturated fatty acids, i.e. palmitic acids, showed stronger antifungal activity than the unsaturated fatty acids, i.e. oleic acid. It suggests that fatty acids might be applicable to exploring for alternative approaches to integrated control of phytopathogens.