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1.
Genes (Basel) ; 14(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-38002973

RESUMO

In higher plants, WRKY transcription factors are broadly involved in a variety of life activities and play an important role in both biotic and abiotic stress responses. However, little is known about the functions of WRKY genes in the popular species, such as Cucurbita maxima (pumpkin), which is planted worldwide. In the present study, 102 CmWRKY genes were identified in the C. maxima genome. Chromosome location, multiple sequence alignment, phylogenetic analysis, and synteny analysis of the CmWRKYs were performed. Notably, we found that silencing CmWRKY22 promoted cucumber mosaic virus (CMV) infection, whereas overexpression of CmWRKY22 inhibited the CMV infection. Subsequently, an electrophoretic mobility shift assay (EMSA) confirmed that CmWRKY22 was able to bind to the W-box at the promoter of CmPR1b, which is a responsive gene of the salicylic acid (SA) signaling pathway. In summary, this study has provided a foundation for the antiviral functions of WRKY transcription factors in C. maxima.


Assuntos
Cucurbita , Infecções por Citomegalovirus , Cucurbita/genética , Filogenia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estresse Fisiológico/genética
2.
Plant Dis ; 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36947833

RESUMO

In August 2022, melon (Cucumis melo), cucumber (Cucumis sativus) and luffa (Luffa aegyptiaca) plants showed virus-like symptoms characteristic of geminiviruses (yellowish green, mosaic patterns and severe curling of leaves, short internodes, and stunting) in 10 greenhouses in Fengxian district and 20 greenhoues in Jiading district of Shanghai, China. Fifty symptomatic leaf samples were randomly collected: 28 from melon, 17 from cucumber, and 5 from luffa. To investigate the etiology of the observed disease, total DNA and RNA was extracted via a DNA extraction kit (Tiangen, Not: DP350) and TRIzol reagent (Sigma-Aldrich, Not: T9424), respectively. Healthy melon plants grown in a growth chamber served as negative control. The DNA and RNA samples were screened for the presence of geminiviruses, Cucurbit chlorotic yellow virus (CCYV), Melon yellow spot virus (MYSV), Cucumber mosaic virus (CMV), Zucchini yellow mosaic virus (ZYMV) and Cucumber green mottle mosaic virus (CGMMV) through PCR or RT‒PCR with geminiviruses (Deng et al. 1994), CCYV, MYSV, CMV, ZYMV and CGMMV (Zeng et al. 2011, 2019) primers. The PCR results showed that 28 melon leaves and 17 cucumber leaves were positive for geminivirus and CCYV, respectively, 5 luffa samples were infected with only geminivirus, and virus was not detected from the healthy plants. These results indicate that these two viruses are widely distributed throughout cucurbit crops in Shanghai, China. All the geminiviruses sequences (approximately 510 bp) were quite similar to each other and were most similar (99.4%) to the Tomato leaf curl New Delhi virus (ToLCNDV) sequence (GenBank Accession No. OP356207) (Li et al. 2022). To confirm the presence of geminiviruses, the segments of DNA-A and DNA-B were amplified by PCR with 4 ToLCNDV-specific primer sets (Mizutani et al. 2011) and sequenced from 10 samples (4 melon, 4 cucumber and 2 luffa). Both DNA-A and DNA-B of the ToLCNDV sequences and features were deposited in GenBank under the accession numbers OQ190939-OQ190948 (DNA-A, 2739 nt) and OQ190949-OQ190958 (DNA-B, 2693 nt). BLASTn analysis of Shanghai isolates of ToLCNDV (DNA-A and DNA-B) showed that the sequences shared nucleotide identities ranged from 99.3% to 100% among them and with values of more than 99.4% nucleotide identity with ToLCNDV isolates from tomato in China (OP356207 and OP356208) (Li et al. 2022). To confirm the virus infection, we have successfully constructed an infectious clone for 0823-1 isolate in the binary plasmid and inoculated melon with and without an infectious clone. The melon plants inoculated with ToLCNDV 15 dpi showed the high accumulation of the virus and displayed symptoms similar to viruses in greenhouse. Based on the complete sequences, results of the molecular phylogenetic analysis (Fig. 2) and infectious clone, these geminiviruses were identified as ToLCNDV. ToLCNDV has been reported to occur and spread by the whitefly (Bemisia tabaci) in many Asian countries (Sohrab et al. 2003; Sohrab et al. 2011; Aamir et al. 2020) and Europe (Juárez et al. 2014; Ruiz et al. 2015; Luigi et al. 2019). Large populations of whiteflies were also present in all our surveyed areas. However, to our knowledge, this is the first report of the occurrence of ToLCNDV in cucurbit plants in China. The presence of ToLCNDV and CCYV can cause severe losses in crop yields or even crop failure. In addition to TYLCV, ToLCNDV is another major geminivirus-induced disease threatening cucurbit and other vegetable production in China.

3.
Insect Sci ; 30(5): 1293-1308, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36478361

RESUMO

Thermal stress usually leads to excessive production of reactive oxygen species (ROS) in all aerobic organisms. Catalases (CAT) are the key antioxidant enzymes, which act as the first line of defense against ROS in the antioxidant pathway. The highly invasive and widely distributed whitefly Bemisia tabaci MED damages plants by feeding as well as by transmitting many plant viruses. Previous studies have shown that strong adaptability to high temperature helps explain the spread of MED around the world. However, the mechanism underlying high temperature adaptation of this pest is not well understood. In this study, 6 CAT genes were identified from the MED genome and transcriptome dataset, among which BtCAT1, BtCAT2, and BtCAT3 were found to be highly expressed in adults. The expression of BtCAT1, BtCAT2, or BtCAT3 increased with induction temperature and induction time. The MED was exposed with mean high temperature (30 °C or 35 °C) and a short-term extremely high temperature (39 °C or 41 °C) after the silencing of BtCAT1, BtCAT2, or BtCAT3 to significantly increased ROS levels by at least 0.5 times and significantly decreased survival rate and fecundity of MED adults. The ROS level in the treated specimens gradually returned to a normal level after 24 h at 25 °C, but the survival rate still declined significantly. Taken together, our results demonstrate that CAT could help B. tabaci adapt to long-term mean high temperatures and short-term extremely high temperatures by eliminating excessive ROS.

4.
Animals (Basel) ; 12(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36359033

RESUMO

Researchers have proposed a variety of classification schemes for the species in the genus Muntiacus (Artiodactyla: Cervidae) based on morphological, molecular, and other evidence, but disputes remain. The Tibetan Yarlung Zangbo Grand Canyon National Nature Reserve in the Eastern Himalayas is an area with a rich diversity of muntjac species. The habitats of many species overlap in this area, but systematic research in this area is lacking. To clarify the species, population and habitat size of muntjac species in the study area, we used camera-traps to monitor muntjacs in the nature reserve from 2013 to 2021 and described and compared morphological characteristics of the muntjac species. Subsequently, we used the MaxEnt model to simulate the habitats of the muntjac species and the Random Encounter Model to estimate the population density and numbers of muntjacs. Three muntjac species were found in the area, namely Muntiacus vaginalis (n = 7788 ± 3866), Muntiacus gongshanensis (n = 6673 ± 2121), and Muntiacus feae (n = 3142 ± 942). The red muntjac has the largest habitat area, the highest population density, and largest size, followed by Gongshan muntjac and Fea's muntjac. This study provides basic data for improving the background knowledge of the animal diversity in the Eastern Himalayan biodiversity hotspot, as well as detailed information and references required by wildlife workers for species identification.

5.
J Control Release ; 331: 164-175, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33450320

RESUMO

The development of nanomaterials to induce antigen-specific immune tolerance has shown promise for treating autoimmune diseases. While PEGylation has been widely used to reduce host immune responses to nanomaterials, its tolerogenic potential has not been reported. Here, we report for the first time that a subcutaneous injection of PEGylated poly(lactide-co-glycolide) (PLGA) nanoparticles containing auto-antigen peptide MOG35-55 without any tolerogenic drugs is sufficient to dramatically ameliorate symptoms after disease onset in an antigen-specific manner in a mouse model of multiple sclerosis. Neither free MOG35-55 nor particles without PEG exhibit this efficacy. Interestingly, mechanistic studies indicate that PEGylation of nanoparticles does not reduce dendritic cell activation through direct nanoparticle-cell interactions. Instead, PEGylated nanoparticles induce lower complement activation, neutrophil recruitment, and co-stimulatory molecule expression on dendritic cells around the injection sitecompared to non-PEGylated PLGA nanoparticles, creating a more tolerogenic microenvironment in vivo. We further demonstrate that the locally recruited dendritic cells traffic to lymphoid organs to induce T cell tolerance. These results highlight the critical role of surface properties of nanomaterials in inducing immune tolerance via subcutaneous administration.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Nanopartículas , Animais , Antígenos , Células Dendríticas , Tolerância Imunológica , Camundongos
6.
Curr Opin Biotechnol ; 66: 131-139, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32795661

RESUMO

One of the grand challenges at the forefront of bionanomaterials is their quick clearance in blood circulation. Progress has been made in understanding nanomaterial-biological system interactions and in developing new strategies to extend the blood circulation time of nanomaterials. Here, we first review interactions between the complement system and nanomaterials as well as clearance pathways in major organs such as the liver, spleen, and kidneys. We then discuss new approaches to prolong the blood circulation of nanomaterials with a focus on grafting polymers and biomimetic camouflages including cell membrane coating and hybrid vesicles. In the end, we provide insights into the pros and cons of these approaches and our perspectives for advancing this field.


Assuntos
Nanoestruturas , Biomimética , Membrana Celular
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-878825

RESUMO

Alzheimer's disease(AD) is a neurodegenerative disease that has no effective drug to cure it. Studies in several AD models have shown that Erigeron breviscapus and its active ingredients(scutellarin and caffeoylquinic acid) could improve/enhance the learning and memory ability, and the mechanisms are associated with inhibiting amyloid β(Aβ) production, aggregation, fibrosis and Aβ neurotoxicity toxicity, regulating cholinergic nervous system, inhibiting oxidative stress and inflammation, inhibiting tau hyperphosphorylation, improving mitochondrial function, and resisting neuronal apoptosis. This article systematically reviewed the research progress of E. breviscapus and its active ingredients for treatment of AD in AD models, in the expectation of providing references for further development of E. breviscapus's medicinal potential.


Assuntos
Humanos , Doença de Alzheimer , Peptídeos beta-Amiloides , Erigeron , Doenças Neurodegenerativas
8.
PeerJ ; 7: e7930, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31660276

RESUMO

The genus Cucurbita comprises many popular vegetable and ornamental plants, including pumpkins, squashes, and gourds, that are highly valued in China as well as in many other countries. During a survey conducted in Zhejiang province, Southeast China in 2016, severe symptoms of viral infection were observed on Cucurbita maxima Duch. ex Lam. Diseased plants showed symptoms such as stunting, mosaicking, Shoe string, blistering, yellowing, leaf deformation, and fruit distortion. Approximately, 50% of Cucurbita crops produced in Jinhua were diseased, causing an estimated yield loss of 35%. In this study, we developed a method using all known virus genomes from the NCBI database as a reference to map small RNAs to develop a diagnostic tool that could be used to diagnose virus diseases of C. maxima. 25 leaf samples from different symptomatic plants and 25 leaf samples from non-symptomatic plants were collected from the experimental field of Jihua National Agricultural Technology Garden for pathogen identification. Small RNAs from each set of three symptomatic and non-symptomatic samples were extracted and sequenced by Illumina sequencing. Twenty-four different viruses were detected in total. However, the majority of the small RNAs were from Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV), and Cucumber mosaic virus (CMV). Mixed infections of these three viruses were diagnosed in leaf samples from diseased plants and confirmed by reverse transcription PCR (RT-PCR) using primers specific to these three viruses. Crude sap extract from symptomatic leaf samples was mechanically inoculated back into healthy C. maxima plants growing under greenhouse conditions. Inoculated plants developed the same disease symptoms as those observed in the diseased plants and a mixed infection of ZYMV, WMV, and CMV was detected again by RT-PCR, thus fulfilling Koch's postulates. The diagnostic method developed in this study involves fewer bioinformatics processes than other diagnostic methods, does not require complex settings for bioinformatics parameters, provides a high level of sensitivity to rapidly diagnose plant samples with symptoms of virus diseases and can be performed cheaply. This method therefore has the potential to be widely applied as a diagnostic tool for viruses that have genome information in the NCBI database.

9.
Carbohydr Polym ; 210: 429-436, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30732779

RESUMO

In this study, one-dimensional (1D) cellulose nanofibers (CNFs) were used to stabilize the dispersion of two-dimensional (2D) montmorillonite (MMT) plates in aqueous system. Then the prepared MMT/CNF solution was simultaneously merged into water soluble corn starch (CS) to obtain CS/MMT/CNF composite freestanding films through a casting method. The reinforcing effect from building blocks of MMT and CNF, interfacial interactions of hydrogen and covalent bonding together led to enhanced tensile strength and Young's modulus, reduced moisture susceptibility and increased transparency of the ternary CS nanocomposites. These extraordinary properties of the ternary nanocomposites clearly point towards a new strategy for designing and fabricating high-performance starch-based nanocomposites by using binary fillers with different geometric shapes and aspect ratio. This kind of ternary nanocomposite can be widely used in food packing and preservation as a biodegradable and green film.

10.
Biomaterials ; 197: 244-254, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30669015

RESUMO

Biological materials are superior to synthetic biomaterials in biocompatibility and active interactions with cells. Here, a new class of biological materials, cell membrane-derived hydrogel scaffolds are reported for harnessing these advantages. To form macroporous scaffolds, vesicles derived from red blood cell membranes (RBCMs) are chemically crosslinked via cryogelation. The RBCM scaffolds with a pore size of around 70 µm are soft and injectable. Highly biocompatible scaffolds are typically made of superhydrophilic polymers and lack the ability to encapsulate and release hydrophobic drugs in a controlled manner. However, hydrophobic molecules can be efficiently encapsulated inside RBCM scaffolds and be sustainedly released. RBCM scaffolds show low neutrophil infiltration after subcutaneous injection in mice, and a significantly higher number of infiltrated macrophages than methacrylate alginate (MA-alginate) scaffolds. According to gene expression and surface markers, these macrophages have an M2-like phenotype, which is anti-inflammatory and immune suppressive. There are also higher percentages of macrophages presenting immunosuppressive PD-L1 in RBCM-scaffolds than in MA-alginate scaffolds. Interestingly, the concentrations of anti-inflammatory cytokine, IL-10 in both types of scaffolds are higher than those in normal organ tissues. This study sheds light on cell membrane-derived hydrogels, which can actively modulate cells in unique ways unavailable to existing hydrogel scaffolds.


Assuntos
Materiais Biocompatíveis/química , Preparações de Ação Retardada/química , Membrana Eritrocítica/química , Alicerces Teciduais/química , Animais , Células Cultivadas , Feminino , Macrófagos/citologia , Camundongos Endogâmicos C57BL , Pirenos/administração & dosagem , Engenharia Tecidual
12.
Carbohydr Polym ; 195: 107-113, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29804957

RESUMO

Hyperbranched poly(trimellitic glyceride) (PTG) plasticizers for starch were prepared by using trimellitic anhydride and glycerol as raw materials in a simple one-step synthesis. The structure and branching degree of PTGs were confirmed by Fourier transformed infrared, gel permeation chromatography and 1H nuclear magnetic resonance. The PTGs as plasticizers were composited with maize starch (S) via cooking and film formation. The structure and mechanical, thermal properties of the plasticized starch composites, and its adhesion to cotton and polyester yarns were studied in details. Results indicated that the PTG/S composites had better mechanical property and thermal stability, and lower moisture absorption than glycerol/starch (GLY/S) with the same content (w/w). With the increase in PTG molecular weight, elongation at break of PTG/S film decreased and tensile strength increased, and moisture absorption of PTGs/S reduced. In addition, PTGs/S had a better effect on adhesion to cotton and polyester yarns than GLY/S.

13.
Carbohydr Polym ; 101: 1109-15, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24299881

RESUMO

Films of thermoplastic starch (TPS) plasticized with different contents of urea were prepared by using a solution casting method. Scanning electron microscopy, X-ray diffraction and IR spectroscopy were used to characterize structures of the TPS films, respectively. Water vapor sorption isotherms and tensile properties of the films were determined. TPS films showed more smooth and transparent in appearance and less B-type crystallinity than the starch film without urea. The effect of urea content on the structure and behavior of the TPS film could be divided in three stages: (1) below urea 10% where urea interacted with starch via H-bonding and the films showed an antiplasticization effect, (2) from urea 10% to 30% where an apparent plasticization effect appeared on the starch because of free urea molecules as the effective plasticizer, and (3) a macroscopic phase separation occurred due to supersaturation of urea when urea content was more than 30%.


Assuntos
Plastificantes/química , Amido/química , Ureia/química , Fenômenos Mecânicos , Modelos Moleculares , Conformação Molecular , Volatilização , Água/química
14.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(1): 60-4, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23651970

RESUMO

OBJECTIVE: To observe serum uric acid (UA) level distribution and explore risk factors of hyperuricemia (HUA) in a large cohort of active and retired employees underwent physical examination. METHODS: Physical examination was arranged for 21 700 active and retired employees from May 2010 to September 2011, 16 416 employees were examined and complete examination data were obtained in 14 044 subjects. The distribution characteristics of UA level and correlations of UA level and HUA prevalence rate with gender, age, body mass index (BMI), systolic pressure (SBP), diastolic pressure (DBP), fasting blood-glucose (FPG), serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) were analyzed. RESULTS: HUA prevalence rate was 11.2% in this cohort, which was significantly higher in males (15.8%) than in females (4.1%, P < 0.05). The UA level and the HUA prevalence rate presented a "J" curve relationship with aging and positively correlated with BMI, SBP, DBP, TG, LDL-C, TC and FPG while negatively correlated with HDL-C. Multiple linear regression analysis showed that SBP, BMI, FPG, TG, and LDL-C were independent risk factors while HDL-C and female gender were the protective factors of HUA(all P < 0.01). Aging and high DBP were independent risk factors of HUA for females (all P < 0.05) and LDL-C was risk factor of HUA for males (P < 0.05). CONCLUSIONS: Serum UA level presents a "J" wave relationship with aging. The risk factors of HUA are increased SBP, BMI, FPG, TG, LDL-C while the protective factors of HUA are female gender and high HDL-C.


Assuntos
Hiperuricemia/epidemiologia , Ácido Úrico/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exame Físico , Prevalência , Fatores de Risco
15.
Huan Jing Ke Xue ; 32(5): 1292-8, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21780582

RESUMO

Nitrogen is the most important element for rice growth, and hyacinth can absorb large quantities of nitrogen and accumulate in their tissues. The field experiment was conducted to investigate the effects of hyacinth mulching on rice nitrogen (N) concentration, uptake, efficiency and allocation at different growth stages. Taked Yun 2645 as a material, the nitrogen uptake and utilization of rice were evaluated under two different levels of N input: low (LN, 120 kg x hm(-2)) and normal N (NN, 240 kg x hm(-2)) in 2009. Main results showed that: (1) Compared with AMB, hyacinth mulching significantly increased N concentration in rice plant over the season, hyacinth mulching significantly increased nitrogen accumulation in rice plant, and the increasing rate was gradual addition from mid-tillering to heading, but from heading to maturity the increasing rate was gradual decline. (2) Hyacinth mulching had no obvious effect on nitrogen allocation pattern in leaves and stems of rice over the season, significantly decreased nitrogen allocation pattern in spikes. (3) Except mid-tillering, hyacinth mulching resulted in the significant decrease in N use efficiency for biomass (NUEp) over the season and in N use efficiency for grain yield (NUEg) at grain maturity, but no effect was observed on nitrogen harvest index (NHI). (4) Nitrogen concentration and accumulation at most growth stages of rice increased with increasing N supply (p < 0.05 or 0.01), but NUEp and NUEg showed the opposite trends. 1(5) nteractions between hyacinth mulching x N were not observed for N uptake and utilization. Hyacinth mulching increased N concentration and N uptake, decreased NUEp and NUEg at most growth stages of rice.


Assuntos
Agricultura/métodos , Hyacinthus/crescimento & desenvolvimento , Nitrogênio/metabolismo , Oryza/crescimento & desenvolvimento , Absorção , Biodegradação Ambiental , Hyacinthus/metabolismo , Nitrogênio/isolamento & purificação , Oryza/metabolismo
16.
Stem Cells ; 24(12): 2618-26, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16888283

RESUMO

Recently, we reported the formation of gut-like structures from mouse ESCs in vitro. To determine whether ESCs provide an in vitro model of gastrointestinal (GI) tracts and their organogenesis, we investigated the morphological features, formation process, cellular development, and regional location within the GI tract by immunohistochemistry, electron microscopy, and reverse transcription-polymerase chain reaction. We also examined the developmental potential by transplantation into kidney capsules. The results demonstrated that Id2-expressing epithelium developed first, alpha-smooth muscle actin appeared around the periphery, and finally, the gut-like structures were formed into a three-layer organ with well-differentiated epithelium. A connective tissue layer and musculature with interstitial cells of Cajal developed, similar to organogenesis of the embryonic gut. Enteric neurons appeared underdeveloped, and blood vessels were absent. Many structures expressed intestinal markers Cdx2 and 5-hydroxytryptamine but not the stomach marker H(+)/K(+) ATPase. Transplants obtained blood vessels and extrinsic nerve growth from the host to prolong life, and even grafts of premature structures did not form teratoma. In conclusion, gut-like structures were provided with prototypical tissue components of the GI tract and are inherent in the intestine rather than the stomach. The formation process was basically same as in gut organogenesis. They maintain their developmental potential after transplantation. Therefore, gut-like structures provide a unique and useful in vitro system for development and stem cell studies of the GI tract, including transplantation experiments.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/transplante , Trato Gastrointestinal/embriologia , Organogênese , Animais , Biomarcadores , Vasos Sanguíneos , Cápsula Glomerular/citologia , Feminino , Feto/embriologia , Trato Gastrointestinal/irrigação sanguínea , Trato Gastrointestinal/inervação , Trato Gastrointestinal/ultraestrutura , Regulação da Expressão Gênica , Camundongos , Camundongos SCID , Modelos Biológicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
Zhongguo Yi Liao Qi Xie Za Zhi ; 29(3): 220-1, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-16124637

RESUMO

Electrocardiograph is a noninvasive medical device most frequently used in diagnosis of cardiovascular diseases. This paper describes the applications, standards, operation and purchase considerations of single-channel, and multi channel electrocardiographs.


Assuntos
Eletrocardiografia/instrumentação , Eletrocardiografia/normas , Segurança de Equipamentos/normas , Doenças Cardiovasculares/diagnóstico , Eletrocardiografia/classificação , Eletrocardiografia Ambulatorial/instrumentação , Eletrocardiografia Ambulatorial/normas , Falha de Equipamento , Humanos , Processamento de Sinais Assistido por Computador/instrumentação
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(7): 879-82, 2004 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-15766097

RESUMO

For ink-jet color inks used for the well-known printers, taking Canon, EPSON, HEWLETT PACKARD and LEXMARK as samples, transmittances of the ink solutions were determined, and then the chromaticity analyses were made, in order to calculate the tristimulus values and the chromatic coordinate of each color sample. Also, the gamuts, chroma values, dominant wavelengths and complementary wavelengths were obtained by using the chromatic method for the samples. In this paper, an empirical formula was suggested for the relationship between the complementary wavelengths of the three primary colors: lambda compl, M approximately equal 10/9 (lambda compl, Y) + 10 and lambda compl, M approximately equal 10/9 (lambda compl, Y) - 20. It was found that the empirical formula is well suited for matching the complementary wavelengths of the three primary colors for ink sets of the samples studied.

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