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1.
Science ; 366(6462): 216-221, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601765

RESUMO

Higher-efficiency, lower-cost refrigeration is needed for both large- and small-scale cooling. Refrigerators using entropy changes during cycles of stretching or hydrostatic compression of a solid are possible alternatives to the vapor-compression fridges found in homes. We show that high cooling results from twist changes for twisted, coiled, or supercoiled fibers, including those of natural rubber, nickel titanium, and polyethylene fishing line. Using opposite chiralities of twist and coiling produces supercoiled natural rubber fibers and coiled fishing line fibers that cool when stretched. A demonstrated twist-based device for cooling flowing water provides high cooling energy and device efficiency. Mechanical calculations describe the axial and spring-index dependencies of twist-enhanced cooling and its origin in a phase transformation for polyethylene fibers.

2.
Nat Commun ; 10(1): 4130, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511532

RESUMO

Increased levels of the urinary albumin-to-creatinine ratio (UACR) are associated with higher risk of kidney disease progression and cardiovascular events, but underlying mechanisms are incompletely understood. Here, we conduct trans-ethnic (n = 564,257) and European-ancestry specific meta-analyses of genome-wide association studies of UACR, including ancestry- and diabetes-specific analyses, and identify 68 UACR-associated loci. Genetic correlation analyses and risk score associations in an independent electronic medical records database (n = 192,868) reveal connections with proteinuria, hyperlipidemia, gout, and hypertension. Fine-mapping and trans-Omics analyses with gene expression in 47 tissues and plasma protein levels implicate genes potentially operating through differential expression in kidney (including TGFB1, MUC1, PRKCI, and OAF), and allow coupling of UACR associations to altered plasma OAF concentrations. Knockdown of OAF and PRKCI orthologs in Drosophila nephrocytes reduces albumin endocytosis. Silencing fly PRKCI further impairs slit diaphragm formation. These results generate a priority list of genes and pathways for translational research to reduce albuminuria.

3.
Opt Lett ; 44(17): 4191-4194, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465360

RESUMO

The influence of nonlinear phase modulations on third-harmonic (TH) conversion in silica microfibers is experimentally demonstrated. By utilizing such influence, enhanced narrow-bandwidth ultraviolet TH is generated at a high signal-to-noise ratio (33 dB) and an average power of several hundred nanowatts. Detailed trends of TH power against input pump power were characterized with peak pump power up to 2.5 kW, and the results agree with predicted features, confirming that harmonic output could be optimized with adaptive control of the phase mismatch.

4.
Med Sci Monit ; 25: 6007-6014, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31402794

RESUMO

BACKGROUND Wogonin (5,7-dihydroxy-8-methoxyflavone), one of flavonoids isolated from the Scutellaria baicalensis, has been regarded as an anticancer candidate because of its maximal efficacy in cancer cells. This study aimed to explore the possible mechanism that wogonin uses to enhance the sensitivity of ovarian cancer cells to cisplatin chemotherapy. MATERIAL AND METHODS The growth inhibition rates of ovarian cancer cells SKOV3/DDP and C13* were assessed by Cell Counting Kit-8 (CCK-8) assay. The apoptosis was assessed under a fluorescence microscope following staining with Hoechst. We further analyzed the expression of Bcl-2, cleaved caspases-3, cleaved-PARP, and phospho-Akt by western blotting. RESULTS In the present study, we found that wogonin reduced proliferation of ovarian cancer cells SKOV3, SKOV3/DDP, OV2008, and C13* in dose- and time-dependent manners and it sensitized cisplatin-induced cytotoxicity. Moreover, treatment with wogonin also increased cisplatin-resistant SKOV3/DDP and C13* cells to low dose cisplatin-induced cell apoptosis. Additionally, such treatment resulted in a significant decrease in phosphorylated Akt. CONCLUSIONS Wogonin could significantly increase the sensitivity of cisplatin-resistant ovarian cancer cells to cisplatin by downregulating the PI3K/Akt pathway.

5.
Mar Pollut Bull ; 149: 110518, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31425840

RESUMO

Twenty-two years of suspended particulate matter (SPM) concentrations in the Yellow River estuary and adjacent sea, China were derived from 532 Landsat and Sentinel 2A/B satellite images. Optimal SPM retrieval model was selected by comparing five state-of-art models using 79 in-situ datasets and recalibrated to ensure consistency among multiple-sensor-derived SPM concentrations. SPM in the estuary, in South Bohai Bay, and Laizhou Bay exhibited distinct temporal variations. 73% and 52% of the interannual and monthly SPM variations near the river mouth were explained by riverine water and sediment discharge, showing impact of the operation of the Xiaolangdi Reservoir and Water-Sediment Regulation Scheme. Land area accretion and erosion in river delta are associated with SPM variation. Riverine impacts on SPM rapidly declined off-shore because of the rapid deposition of the coarse-grain sediment. Ocean current and wind-wave forces explained high concentrations and intra-annual variations of SPM in the South Bohai Bay and Laizhou Bay.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31350643

RESUMO

PURPOSE: Radiofrequency ablation along the posterior wall of the left atrium may lead to atrioesophageal fistula due to esophageal thermal injury. The purpose of our study was to prospectively investigate whether ablation guided by soluble contrast esophageal visualization (SCEV) reduces injury during atrial fibrillation (AF) ablation. METHODS: Seventy-eight patients with paroxysmal AF undergoing circumferential pulmonary vein isolation (PVI) were randomized to a SCEV group (n = 39) and control group without visualization (n = 39). Cine imaging of the esophagus was performed during soluble contrast swallowing at the beginning of ablation, after adjacent ipsilateral PVI and at the end of the procedure. The ablation lesion set was modified to avoid radiofrequency delivery within the contrast esophagram boundaries. In the control group, a single final ingestion was performed at the end of the procedure. Esophageal injury was assessed by esophagogastroscopy within 24 h in all patients. RESULTS: In the control group, the ablation lesion crossed over the esophagus in 46.2% of patients, whereas in SCEV group, the ablation line violated the boundaries of the esophagus unavoidably in 15.4% of patients (confidence interval (CI); 1.61-13.98, p = 0.003). The incidence of esophageal injury was significantly lower in patients that underwent ablation with SCEV (5.1% vs. 20.5%, CI; 0.04-1.06, p = 0.042). Regardless of randomization group, patients who received ablation which overlapped the esophagus had a higher incidence of esophageal injury compared with those without overlap (37.5 vs. 1.9%, CI; 3.73-271.37, p = 0.000). CONCLUSIONS: Esophageal contrast visualization helps to reduce the potential for esophageal injury during paroxysmal AF ablation. This simple procedural adjunct has important implications to improve safety of paroxysmal AF ablation procedures globally.

7.
Biomed Pharmacother ; 117: 109064, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31226633

RESUMO

BACKGROUND: Cervical cancer has been one of the most common cancer in women worldwide. However, the detailed mechanism underlying circMTO1-regulated cervical cancer remains unclear. METHODS: RT-qPCR and westernblot were used to examine genes expression levels. Wound healing assay and transwell invasion assay were utilized to probe migration and invasion abilities of cervical cancer cells. In addition, cell viability and apoptosis were measured by MTT and TUNEL assay, respectively. Finally, we employed bioinformatic approach to analyze gene expression levels in clinical cervical cancer tissues. RESULTS: circMTO1 was shown to be greatly upregulated in cervical cancer cell lines and tumors. circMTO1 directly interacts with miR-6893. miR-6893 could restore circMTO1-regulated migration, invasion and chemoresistance of cervical cancer cells. Furthermore, we identified S100A1 as downstream effector for circMTO1/miR-6893-induced tumorigenesis of cervical cancer cells. Besides, westernblot analyses demonstrated that circMTO1 and miR-6893 inhibitor enhanced Beclin1 expression and downregulated p62 level. We found that autophagy inhibitor 3-MA could revert cell viability and apoptosis of HeLa regulated by circMTO1 and miR-6893 inhibitor. More importantly, the bioinformatic results showed the dysregulated expression patterns of circMTO1, miR-6893 and S100A1 in human clinical cervical cancer tissues. CONCLUSIONS: In summary, we reveal, for the first time, a novel mechanism of circMTO1/miR-6893 in tumorigenesis and chemoresistance of cervical cancer. Our findings support the notion of developing the new therapies and biomarkers by targeting circMTO1 for cervical cancer.

8.
J Cardiovasc Pharmacol ; 73(6): 373-382, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31162246

RESUMO

Puerarin is used to treat cardiovascular diseases due to its anti-inflammatory and antifibrotic effects. However, its mechanism of action in atrial fibroblasts is unknown. In this study, we investigated the autophagy pathway and molecular changes in angiotensin II (AngII)-stimulated atrial fibroblasts in response to puerarin treatment. Atrial fibroblasts were cultured and then subjected to stimulation with AngII and puerarin or other chemical drugs (3-MA, CQ, and SP600125). Quantitative real-time polymerase chain reaction and Western blot experiments were used to quantify the expression levels of mRNA and protein. mCherry-GFP-LC3 adenovirus was applied to reflect the autophagic flux. The results showed aggravating levels of autophagy and collagen deposit in the presence of AngII. Puerarin inhibited autophagy and decreased collagen secretion in a dose-dependent manner in atrial fibroblasts. Furthermore, phosphorylation of JNK was down-regulated in response to puerarin, whereas phosphorylation of Akt and mammalian target of rapamycin (mTOR) was upregulated. Interestingly, reduced autophagy and collagen secretion were observed when the JNK signaling pathway was blocked using SP600125. We also observed upregulation of Akt and mTOR phosphorylation in the presence of SP600125. These results suggest that puerarin exerts its antifibrotic effect in atrial fibroblasts partly through the inhibition of autophagy. Furthermore, the mechanism of action of puerarin in fibroblast autophagy seems to be mediated partly through JNK-Akt-mTOR signaling.

9.
Ecotoxicol Environ Saf ; 180: 439-448, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31117015

RESUMO

Nitrogen (N) plays crucial roles in chlorophyll concentration, photosynthesis, and stress tolerance of plant leaves. This study conducted a greenhouse experiment combined with Cd and N treatments to elucidate the mechanism underlying the influence of N on Cd accumulation and acclimation strategy in Populus leaves. Chlorophyll concentration and net photosynthetic rates (A) in leaves were unaltered by Cd exposure regardless of N condition. Nitrogen availability alter acclimation strategy of poplar leaves under cadmium exposure. Under sufficient N, Cd accumulation in leaves was elevated with increased intensity and duration of Cd exposure; Cd accumulation reached ca. 28 µg g-1 dry weight and 260 µg plant-1 after 60 days of exposure to high level of Cd (20 mg Cd kg-1 soil), and this finding indicates a large potential for Cd phytoextraction. Poplar leaves exhibited high capacity for antioxidant defense and stress tolerance and avoided oxidative damage under high Cd exposure. The levels of phytohormones and antioxidants in leaves and the relative expressions of critical genes encoding antioxidant enzymes were up-regulated under sufficient N condition. Nitrogen deficiency decreased chlorophyll concentration and net photosynthetic rates (A) and interfered with the production of N metabolites, resulting in a low level of phytohormones and antioxidants that are responsible for stress tolerance. The low levels of Cd accumulation in leaves may be a self-protecting strategy to prevent severe oxidative damage due to the decreased capacities for stress tolerance under N deficiency.


Assuntos
Aclimatação/efeitos dos fármacos , Cádmio/toxicidade , Nitrogênio/metabolismo , Populus/efeitos dos fármacos , Poluentes do Solo/toxicidade , Aclimatação/fisiologia , Antioxidantes/metabolismo , Cádmio/metabolismo , Clorofila/metabolismo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Populus/metabolismo , Solo/química , Poluentes do Solo/metabolismo
10.
Biomed Pharmacother ; 115: 108957, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31082770

RESUMO

BACKGROUND: Cervical cancer has been shown to be one of the leading cancer-related death causes all over the world. Several studies demonstrates that hsa_circ_0023404 plays a crucial role in progression of cervical cancer; however, the detailed mechanism of hsa_circ_0023404 regulating cervical cancer metastasis and chemoresistance remains unclear. METHODS: We used RT-qPCR and westernblot approach to detect expression levels of various genes in cervical tumors and cancer cells. To examine invasion and lymphatic vessel formation of Human Dermal Lymphatic Endothelial Cells (HDLEC), transwell invasion assay and lymphatic vessel assay were utilized in the presence of conditioned medium of HeLa and SiHa cells. To examine direct interaction between hsa_circ_0023404 and miR-5047, bioinformatic analysis and luciferase reporter assay were used. Besides, MTT and flow cytometry analysis were conducted to assess cell viability and apoptosis rate of HeLa cell. RESULTS: hsa_circ_0023404 knockdown attenuates invasion of cervical cancer cells and lymphatic vessel formation of HDLEC cells. hsa_circ_0023404 directly interacted with miR-5047. Moreover, miR-5047 inhibitor-transfected HeLa and SiHa cells enhanced invasion and lymphatic vessel formation of HDLEC cells. More interestingly, we confirmed that hsa_circ_0023404 knockdown and miR-5047 mimic downregulated the expression levels of VEGFA. The functional rescue experiments indicated VEGFA acted as key factor for hsa_circ_0023404- and miR-5047-regulated invasion and lymphatic vessel formaion. Ultimately, hsa_circ_0023404 and VEGFA were upregulated and showed positive correlation in cervical tumors, while miR-5047 was downregulated and showed negative correlation with hsa_circ_0023404 and VEGFA. On the other hand, autophagy-associated genes (Beclin1 and p62) were dysregulated in hsa_circ_0023404 depleted and overexpressed HeLa cells. hsa_circ_0023404 knockdown inhibited cell viability of cells, which was obviously abolished by autophagy inhibitor 3-MA in the presence of various concentrations of Cisplatin. Consistently, apoptosis rate was remarkably elevated in hsa_circ_0023404 depleted cells and diminished in hsa_circ_0023404 overexpressed cells under treatment of 2 µg/ml Cisplatin. CONCLUSIONS: Here, we reveal a novel role of hsa_circ_0023404 for cervical cancer metastasis and chemoresistance by regulating miR-5047. Our findings help understand mechanism underlying cervical cancer and development of therapeutical approaches for treating cervical cancer.

11.
Opt Express ; 27(7): 9684-9695, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045117

RESUMO

The performance of distributed optical fiber acoustic sensor as a function of parameters such as the linewidth of the laser, the probe pulse width, and the amplitude and frequency of perturbation is experimentally studied. The aim of this study is to experimentally confirm the outcome of the simulation results obtained previously. It is shown that the experimental and simulation results are in good agreement, and the precision of the sensing system depends on the pulse width and linewidth of the probe pulse, as well as the frequency and amplitude of the perturbation. It is shown that the sensing precision of the system can be enhanced by reducing the width of the probe pulse while increasing the linewidth of the laser.

12.
J Clin Periodontol ; 46(6): 608-622, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30989678

RESUMO

AIM: Oxidative stress (OS) biomarkers have been detected in saliva and gingival crevicular fluid (GCF) during chronic periodontitis (CP) progression; however, the relationship between OS biomarkers and CP progression remains elusive. The purpose of this meta-analysis is to investigate the relationship between local OS biomarkers and CP. METHODS: This review was conducted through a systematic search from three databases. Studies on CP participants were included as an experimental group, and studies on periodontally healthy (PH) participants were included as a control. Mean effects were expressed as standardized mean difference with their associated 95% confidence intervals. RESULTS: From a total of 2,972 articles, 32 articles fulfilled the inclusion criteria. We found a significant decrease of total antioxidant capacity and a significant increase of malondialdehyde (MDA), nitric oxide, total oxidant status (TOS), and 8-hydroxy-deoxyguanosine levels in the saliva of CP patients. Moreover, we also found an elevation of MDA level in GCF of CP group when compared with the PH group. There were no significant differences of salivary and GCF superoxide dismutase levels, salivary glutathione peroxidase level, and GCF TOS level between two groups. However, a high heterogeneity was observed among evaluated studies. CONCLUSIONS: Despite the limitations of this study, the result of our meta-analysis supported the rationale that there was a direct link between CP and OS-related biomarkers' levels in the local site, indicating the important role of OS in the onset and development of CP.

13.
ACS Chem Neurosci ; 10(5): 2560-2575, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30817119

RESUMO

Infectious exposure during the perinatal period may predispose to permanent neurological disorders in later life. Here we investigated whether changes in interleukin-1ß (IL-1ß) are associated with cognitive dysfunction in later life of septic neonatal rats through suppression of neurogenesis in the hippocampus. Sprague-Dawley rats (1-day old) administered lipopolysaccharide (LPS) showed upregulated expression of IL-1ß and IL-1 receptors in the hippocampus. At 28 days of age, rats showed longer escape latencies and decreased numbers of crossings after LPS administration. This was coupled with increased numbers of glial fibrillary acidic protein positive (GFAP+) astrocytes and decreased numbers of neuronal nuclei positive (NeuN+) cells. The numbers of sex-determining region Y-box 2 positive (SOX2+) and doublecortin positive (DCX+) cells were decreased at 1 and 3 days but was increased at 7 and 14 days. The proliferation of SOX2+ cells was inhibited at 1 and 3 days but increased at 7 and 14 days. In vitro IL-1ß administration suppressed the proliferation of neural progenitor cells (NPCs) in neurospheres derived from the hippocampus. GFAP expression was upregulated in differentiated NPCs treated with IL-1ß for 4 days, but expression of DCX and microtubule associated protein-2 (MAP2) was decreased. Remarkably, the Notch signaling pathway involved in antineurogenic and progliogenic differentiation of NPCs was activated after IL-1ß administration. The results show that following LPS injection in neonatal rats, microglia were activated and generated excess amounts of IL-1ß in the hippocampus. It is suggested that this might have contributed to inhibiting neurogenesis but promoting gliogenesis of NPCs via activation of the Notch signaling pathway and maybe one of the causes for cognitive dysfunction in septic neonatal rats in later life.

14.
Opt Express ; 26(19): 25399-25407, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30469642

RESUMO

A distributed optical fiber dynamic strain sensor also known as a distributed acoustic sensor (DAS) based on two-mode fiber is demonstrated. By using φ-OTDR interrogation technique, the backscattered light from higher order modes can be used to fully quantify vibrations along the sensing fiber. In addition, by combining the results obtained from different modes, 2.52dB improvement in noise floor is achieved. These results confirm that few-mode fibers can be used for DAS applications.

15.
Langmuir ; 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30485107

RESUMO

One-dimensional microscale SERS-active interfaces have been intriguing as a newly emerging class of SERS interfaces compared to conventional macroscale SERS substrates. In this work, a stable surface-nanostructured single silver nanowire was fabricated. The nanostructures on the nanowire are formed by nanoscale silver crystal dots with diameters of 20-50 nm. The SERS signals of the crystal violet probe molecules adsorbed on the nanostructures are dramatically enhanced by both electromagnetic and chemical effects. The hot spots generated at the junctions of adjacent nanoscale dots yield highly efficient surface plasmon resonance. Simultaneously, the charge transfer on the atomic-scale silver cluster located at the nanostructured interface causes an enhancement similar to a Raman resonance. The intensity distributions of the SERS peaks on the surface-nanostructured single nanowire are characterized by SERS mapping. It is found that, although the intensities of the SERS peaks are different, their SERS mapping images show uniform SERS enhancement distributions, whereas the noticeable SERS intensity distributions on the single smooth silver nanowire are mainly located on the two ends of the nanowire. The large number of nanoscale crystal dots along with the atomic-scale silver clusters are uniformly and densely distributed on the surface of the single roughened nanowire; these structural attributes induce a uniform and large surface plasmon resonance and charge transfer enhancements on the entire surface of the nanowire. This work indicates that the surface-nanostructured single silver nanowire, synthesized using a quite simple preparation method, performs as an excellent one-dimensional microscale SERS substrate with uniform and high enhancement characteristics, which shows high potential for applications as a new class of SERS-active substrates. Furthermore, the higher enhancement factor of the microscale SERS interfaces can be achieved by introducing other roughened nanowires to assemble a dimer and a trimer as micro SERS substrates, which is consistent with the dark field (DF) measurements.

16.
Chemistry ; 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30353588

RESUMO

As the main component of syngas, reducing CO2 to CO with high selectivity through photocatalysis could provide a sustainable way to alleviate energy shortage issues. Developing a photocatalytic system with low cost and high performance that is environmentally friendly is the ultimate goal towards CO2 photoreduction. Herein, an efficient and economic three-component heterojunction photocatalyst is designed and fabricated for converting CO2 to CO in the absence of organic sacrificial agents. The heterojunction is made of Cu2-x S nanotubes coated with a carbon layer (C-Cu2-x S) and g-C3 N4 . By using the classical MOF material HKUST-1 as a precursor, hollow tubular-like metal sulfides (C-Cu2-x S) with carbon coating were synthesized and further loaded on g-C3 N4 , forming a three-component heterojunction C-Cu2-x S@g-C3 N4 . The carbon coat in C-Cu2-x S@g-C3 N4 acts as an electron reservoir, which facilitates electron-hole pair separation. The optimized C-Cu2-x S@g-C3 N4 acted as a photocatalyst in CO2 reduction with a high reactivity of 1062.6 µmol g-1 and selectivity of 97 %. Compared with bare g-C3 N4 (158.4 µmol g-1 ) and C-Cu2-x S, the reactivity is nearly 7 and 23-fold enhanced and this CO generation rate is higher than most of the reported Cu2 S or g-C3 N4 composites under similar conditions. The prominent activity may result from enhanced light adsorption and effective charge separation. This work might open up an alternative method for the design and fabrication of high-performance and low-cost photocatalysts for efficiently and durably converting CO2 to CO with high selectivity.

17.
Res Vet Sci ; 119: 259-261, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30055409

RESUMO

During the past years epizootic outbreaks of mucoid enteropathy syndrome (MES) disease have emerged and spread rapidly in rabbit farms in East China causing great economic losses. To investigate the nature and evolution of the disease, two trials were conducted in an attempt to reproduce the disease and to assess the microbiota cecal profile changes associated with the disease. In the first trial, twenty 6-week-old New Zealand White healthy rabbits were assigned randomly to one of two treatments: 1) Inoculation with 2.0 mL of cecal content (inoculum) from dead rabbits affected with MES; 2) No inoculation or control group. In the second trial, V3 - V4 regions of 16S ribosomal genes from three virulent (MES) and two non-virulent (healthy) cecal samples were amplified and sequenced for microbiota genomic characterization. The mucoid enteropathy syndrome was reproduced using a virulent cecal material (inoculum). The mortality rates for treatments 1 and 2 were 70% and 0%, respectively. Clinical signs and gross lesions of affected rabbits consisted of bloated abdomen, cecal impaction, presence of variable amounts of gelatinous mucus particularly in the colon, mucus excretion and diarrhea of low intensity. The disease that emerged in China is similar to the epizootic rabbit enteropathy (ERE) described in Europe. However, microbiota cecal changes associated with the disease differed from those in ERE. Here, a comprehensive analysis of mucoid enteropathy syndrome disease is presented, which should be carefully monitored.

18.
IEEE Trans Cybern ; 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29994571

RESUMO

In this paper, the distributed adaptive event-triggered fault-tolerant consensus of general linear multiagent systems (MASs) is considered. First, in order to deal with multiplicative fault, a distributed event-triggered consensus protocol is designed. Using distributed adaptive online updating strategies, the computation of the minimum eigenvalue of Laplacian matrix is avoided. Second, some adaptive parameters are introduced in trigger function to improve the self-regulation ability of event-triggered mechanism. The new trigger threshold is both state-dependent and time-dependent, which is independent of the number of agents. Then sufficient conditions are derived to guarantee the leaderless and leader-following consensus. On the basis of this, the results are extended to the case of actuator saturation. It is proved the Zeno-behavior of considered event-triggered mechanism is avoided. At last, the effectiveness of the proposed methods are demonstrated by three simulation examples.

19.
Opt Express ; 26(11): 14375-14391, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29877477

RESUMO

Conventional deconvolution methods assume that the microscopy system is spatially invariant, introducing considerable errors. We developed a method to more precisely estimate space-variant point-spread functions from sparse measurements. To this end, a space-variant version of deblurring algorithm was developed and combined with a total-variation regularization. Validation with both simulation and real data showed that our PSF model is more accurate than the piecewise-invariant model and the blending model. Comparing with the orthogonal basis decomposition based PSF model, our proposed model also performed with a considerable improvement. We also evaluated the proposed deblurring algorithm. Our new deblurring algorithm showed a significantly better signal-to-noise ratio and higher image quality than those of the conventional space-invariant algorithm.

20.
J Invertebr Pathol ; 154: 95-101, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29660347

RESUMO

Shrimp hemocyte iridescent virus (SHIV) is a recently reported shrimp virus, which threats the cultured white-leg shrimp Litopenaeus vannamei and can cause huge economic loss in shrimp farming industry in China. A quantitative real time polymerase chain reactio (qPCR) assay was developed using a TaqMan probe to detect and quantify SHIV. A pair of qPCR primers, which amplify a 188 bp DNA fragment, and a TaqMan probe were selected from ATPase gene (ORF114R) of the SHIV genome. The primers and TaqMan probe used in this assay were shown to be specific for SHIV and did not react with White spot syndrome virus (WSSV), Infectious hypodermal and hematopoietic necrosis virus (IHHNV), Hepatopancreatic parvovirus (HPV), Vibrio parahaemolyticus causing acute hepatopancreatic necrosis disease (VPAHPND), and Enterocytozoon hepatopenaei (EHP), or healthy shrimp DNA. The detection limit of the qPCR method was as low as 4 copies per reaction. The diagnostic sensitivity and the diagnostic specificity of the qPCR compared with nested PCR were 95.3% and 99.2%, respectively. The resulting standard curves showed high correlation coefficient values (R2 = 0.998) in the range of 4 × 109 to 4 × 100 DNA copies/reaction. Test of farm samples showed that SHIV was detected in L. vannamei, Fenneropenaeus chinensis and Macrobrachium rosenbergii contained SHIV ranged from 1.21E+02 to 7.95E+07 copies (µg DNA)-1. Quantitative detection of different tissues in artificial infected shrimp showed that haemolymph contained the highest SHIV load and muscle contained lowest SHIV load.

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