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1.
J Biomed Inform ; 100: 103319, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31655272

RESUMO

To provide natural simulated objects and intuitive user interaction in medical education and training, we propose a naked eye 3D display and interaction system. The current 3D rendering algorithms for naked eye 3D displays are not suitable for medical use, due to the requirements of displaying and interacting with high quality medical images and simulating soft tissues. Because the traditional 3D rendering procedure and vertex indexing in collision detection require substantial computing power when using a naked eye 3D display, the current method cannot achieve fluent displays and interactions. Thus, we develop a novel octree-based 3D rendering and interaction algorithm for high quality medical models to improve the rendering rate and obtain smooth human machine interactions when using the naked eye 3D display device. We also valuate the soft-body phantom simulation of the naked eye 3D display device by combining the traditional 3D rendering algorithm with the elastic 3D simulation to simulate deformable tissues. We integrate an incremental interaction method and a Kalman filter-based hand tracking method to achieve a larger user interaction range and robust hand tracking. We used the proposed system to perform human-computer interactions with rigid phantoms and soft-body phantoms. The experimental results showed that the proposed rendering algorithm for rigid phantoms could achieve higher rendering performance (50 FPS) than the traditional rendering algorithm (9.8 FPS). The user experiments showed that the 3D simulation system equipped with the enhanced rendering algorithm could achieve fluent interactions when using the naked eye 3D display, thus promoting education experiences and reducing task completion times.

2.
Opt Express ; 27(15): 20421-20434, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510136

RESUMO

We propose a novel full-parallax autostereoscopic display based on a lenticular tracking method to achieve separation between the viewing angle and image resolution and to improve these two parameters simultaneously. The proposed method enables the viewing angle to be independent of the image resolution and has the potential to solve the long-term trade-off problem in integral photography. By employing the lenticular lens array instead of the micro-lens array in integral photography with viewing tracking, the proposed method shows a high-image resolution and wide viewing angle 3D display with full parallax. A real-time tracking and rendering algorithm for the display method is also proposed in this study. The experimental results, compared with those of the conventional integral photography display and the tracking-based integral photography display, demonstrate the feasibility of this lenticular tracking display technology and its advantages in display resolution and viewing angle, suggesting its potential in practical three-dimensional applications.

3.
Food Chem ; 294: 187-193, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126451

RESUMO

The grain formation stage is a critical stage that affects grain starch quality and frequently overlaps the rainy season in southern China for waxy maize production. Two waxy maize varieties were grown under control and waterlogging conditions during grain formation (1-15 days after pollination) to probe the effects of oversaturated soil moisture on starch structural and functional characteristics. Results indicated that waterlogging during grain formation decreased the size of starch granule, proportion of large granule (d > 15 µm) and ratio of medium-length chains (DP 10-24) in amylopectin, whereas the percentage of high-molecular-weight molecules were increased. Compared with the control, the percentage of ordered starch was increased by waterlogging for both varieties. The changes in starch internal structure under waterlogging had no influence on thermal stability, increased the maximum thermal decomposition ratio and pasting temperatures, and reduced pasting viscosity characteristics in both varieties.


Assuntos
Amido/química , Amilopectina/química , Peso Molecular , Solo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Termogravimetria , Viscosidade , Zea mays/química , Zea mays/metabolismo
4.
Polymers (Basel) ; 11(3)2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30960544

RESUMO

Food corruption and spoilage caused by food-borne pathogens and microorganisms is a serious problem. As a result, the demand for antibacterial drugs in food packaging is growing. In this review, biodegradable and non-biodegradable materials for food packaging are discussed based on their properties. Most importantly, antibacterial agents are essential to inhibit the growth of bacteria in food. To keep food fresh and prolong the shelf life, different kinds of antibacterial agents were used. The composition and application of natural antibacterial agents and synthetic antibacterial agents are discussed. Compared with natural antibacterial agents, synthetic antibacterial agents have the advantages of low cost and high activity, but their toxicity is usually higher than that of natural antibacterial agents. Finally, future development of antimicrobial food packaging is proposed. It is an urgent problem for researchers to design and synthesize antibacterial drugs with high efficiency and low toxicity.

5.
Plant Cell Rep ; 38(5): 533-543, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30725169

RESUMO

KEY MESSAGE: The first report of the cloning and characterization of the flowering time-regulating genes GI and CO homologs from loquat. Flowering time is critical for successful reproduction in plants. In fruit trees, it can also influence the fruit yield and quality. In the previous work, we cloned the important florigen one EdFT and two EdFDs from wild loquat (Eriobotrya deflexa Nakai forma koshunensis); however, the upstream transcription factors are still unknown. The photoperiod pathway genes GIGANTEA (GI) and CONSTANS (CO) have been reported to mainly regulate FT expression in model plants. In this work, we first cloned photoperiod pathway orthologs EdGI and EdCO from E. deflexa Nakai f. koshunensis. Phylogenetic analysis showed they are highly conserved to those from Arabidopsis. They are mainly expressed in the leaves. The EdGI and EdCO were localized in the nucleus. Their expression showed in photoperiodic regulation, while the EdCO transcripts reached the peak at different periods from that of CO in Arabidopsis. Moreover, EdCO significantly activated the EdFT promoter activity. In the transgenic Arabidopsis, downstream-flowering genes like FT and AP1 were obviously upregulated, and consequently resulted in early-flowering phenotype compared to the wild type. These data revealed that the EdGI and EdCO may play a similar role as GI and CO in Arabidopsis, and regulate flower initiation in loquat.


Assuntos
Eriobotrya/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Eriobotrya/fisiologia , Flores/metabolismo , Flores/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Fotoperíodo , Filogenia
6.
J Sci Food Agric ; 98(3): 1008-1015, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28718948

RESUMO

BACKGROUND: Waxy maize (Zea mays L. sinensis Kulesh) suffers short-term exposure to high temperature during grain filling in southern China. The effects of such exposure are poorly understood. RESULTS: Starch granule size was increased by 5 days' short-term heat stress (35.0 °C) and the increase was higher when the stress was introduced early. Heat stress increased the iodine binding capacity of starches and no difference was observed among the three stages. Starch relative crystallinity was increased and swelling power was decreased only when heat stress was introduced early. Heat stress also increased the pasting viscosity, and this effect became more pronounced with later applications of stress. Heat stress reduced starch gelatinization enthalpy, and the reduction gradually increased with later exposures. Heat stress increased the gelatinization temperature and retrogradation enthalpy and percentage of the samples, with the increases being largest with earlier introduction of high temperature. CONCLUSION: Heat stress increased the pasting viscosities and retrogradation percentage of starch by causing change in granule size, amylopectin chain length distribution and crystallinity, and the effects observed were more severe with earlier introduction of heat stress after pollination. © 2017 Society of Chemical Industry.


Assuntos
Extratos Vegetais/química , Amido/química , Zea mays/crescimento & desenvolvimento , Amilopectina/química , China , Temperatura Alta , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Amido/metabolismo , Viscosidade , Zea mays/química , Zea mays/metabolismo
7.
Turk J Biol ; 42(3): 224-230, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30814884

RESUMO

Two cryoprotectant solutions, including trimethylamine oxide (TMAO) and dimethyl sulfoxide (DMSO), and several loading durations were used to evaluate the cryopreservation of the shoot tip of Eriobotrya plants. The best results for regrowth (59.91%) were obtained from 10% TMAO compared to 10% DMSO as cryoprotectant, although nonsignificant differences were found for survival between the two cryoprotectants. We detected pronounced effects of loading duration on survival and regrowth rates of shoot tips. The maximum regrowth (56.36%) was observed at 9 h of loading duration. The cryoprotectants and loading durations greatly affected the regrowth of Eriobotrya shoot tips, and TMAO could be introduced as a nontoxic and efficient cryoprotectant. These results could lay a foundation for the cryopreservation of Eriobotrya.

8.
J Opt Soc Am A Opt Image Sci Vis ; 34(5): 804-812, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28463324

RESUMO

Quality of three-dimensional (3D) autostereoscopic displays is mainly influenced by the mismatch between the optical apparatus setups and image generation algorithms. In this paper, we take the optical apparatus setups into consideration and present an accurate 3D autostereoscopic display method using optimized parameters through quantitative calibration. Rotational and translational alignments are operated quantitatively to rectify the optical apparatus. In addition, the main parameters in a 3D display are evaluated for accurate 3D image rendering. Using the proposed method, the 3D autostereoscopic display can be calibrated quantitatively and provide 3D images with accurate spatial information. Experiments verified the availability and feasibility of the proposed method.

9.
Sci Rep ; 4: 6300, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25199907

RESUMO

A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Mutação Puntual/genética , Coloração e Rotulagem/métodos , Carcinoma Hepatocelular/genética , Detecção Precoce de Câncer/métodos , Vidro , Humanos , Interações Hidrofóbicas e Hidrofílicas , Neoplasias Hepáticas/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Respiração , Vapor , Propriedades de Superfície , Proteína Supressora de Tumor p53/genética , Molhabilidade
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