Vertically spliced tabletop light field cave display with extended depth content and separately optimized compound lens array.

Tabletop three-dimensional light field display is a kind of compelling display technology that can simultaneously provide stereoscopic vision for multiple viewers surrounding the lateral side of the device. However, if the flat panel light field display device is simply placed horizontally and displayed directly above, the visual frustum will be tilted and the 3D content outside the display panel will be invisible, the large oblique viewing angle will also lead to serious aberrations. In this paper, we demonstrate what we believe to be a new vertical spliced light field cave display system with an extended depth content. A separate optimization of different compound lens array attenuates the aberration from different oblique viewing angles, and a local heating fitting method is implemented to ensure the accuracy of fabrication process. The image coding method and the correction of the multiple viewpoints realize the correct construction of spliced voxels. In the experiment, a high-definition and precisely spliced 3D city terrain scene is demonstrated on the prototype with a correct oblique perspective in 100-degree horizontal viewing range. We envision that our research will provide more inspiration for future immersive large-scale glass-free virtual reality display technologies.

True-color light-field display system with large depth-of-field based on joint modulation for size and arrangement of halftone dots.

A true-color light-field display system with a large depth-of-field (DOF) is demonstrated. Reducing crosstalk between viewpoints and increasing viewpoint density are the key points to realize light-field display system with large DOF. The aliasing and crosstalk of light beams in the light control unit (LCU) are reduced by adopting collimated backlight and reversely placing the aspheric cylindrical lens array (ACLA). The one-dimensional (1D) light-field encoding of halftone images increases the number of controllable beams within the LCU and improves viewpoint density. The use of 1D light-field encoding leads to a decrease in the color-depth of the light-field display system. The joint modulation for size and arrangement of halftone dots (JMSAHD) is used to increase color-depth. In the experiment, a three-dimensional (3D) model was constructed using halftone images generated by JMSAHD, and a light-field display system with a viewpoint density of 1.45 (i.e. 1.45 viewpoints per degree of view) and a DOF of 50 cm was achieved at a 100 ° viewing angle.

Multiparametric liver MRI for predicting early recurrence of hepatocellular carcinoma after microwave ablation.

BACKGROUND: High early recurrence (ER) of hepatocellular carcinoma (HCC) after microwave ablation (MWA) represents a sign of aggressive behavior and severely worsens prognosis. The aim of this study was to estimate the outcome of HCC following MWA and develop a response algorithmic strategy based on multiparametric MRI and clinical variables. METHODS: In this retrospective study, we reviewed the records of 339 patients (mean age, 62 ± 12 years; 106 men) treated with percutaneous MWA for HCC between January 2014 and December 2017 that were evaluated by multiparametric MRI. These patients were randomly split into a development and an internal validation group (3:1). Logistic regression analysis was used to screen imaging features. Multivariate Cox regression analysis was then performed to determine predictors of ER (within 2 years) of MWA. The response algorithmic strategy to predict ER was developed and validated using these data sets. ER rates were also evaluated by Kaplan-Meier analysis. RESULTS: Based on logistic regression analyses, we established an image response algorithm integrating ill-defined margins, lack of capsule enhancement, pre-ablative ADC, ΔADC, and EADC to calculate recurrence scores and define the risk of ER. In a multivariate Cox regression model, the independent risk factors of ER (p < 0.05) were minimal ablative margin (MAM) (HR 0.57; 95% CI 0.35 - 0.95; p < 0.001), the recurrence score (HR: 9.25; 95% CI 4.25 - 16.56; p = 0.021), and tumor size (HR 6.21; 95% CI 1.25 - 10.82; p = 0.014). Combining MAM and tumor size, the recurrence score calculated by the response algorithmic strategy provided predictive accuracy of 93.5%, with sensitivity of 92.3% and specificity of 83.1%. Kaplan-Meier estimates of the rates of ER in the low-risk and high-risk groups were 6.8% (95% CI 4.0 - 9.6) and 30.5% (95% CI 23.6 - 37.4), respectively. CONCLUSION: A response algorithmic strategy based on multiparametric MRI and clinical variables was useful for predicting the ER of HCC after MWA.

Multiparametric MRI-based Radiomics approaches on predicting response to neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer.

PURPOSE: To investigate the value of multiparametric MRI-based radiomics on predicting response to nCRT in patients with rectal cancer. METHODS: This study enrolled 193 patients with pathologically confirmed LARC who received nCRT treatment between Apr. 2014 and Jun. 2018. All patients underwent baseline T1-weighted (T1W), T2-weighted (T2W) and T2-weighted fat-suppression (T2FS) MRI scans before neoadjuvant chemoradiotherapy. Radiomics features were extracted and selected from the MRI data to establish the radiomics signature. Important clinical predictors were identified by Mann-Whitney U test and Chi-square test. The nomogram integrating the radiomics signature and important clinical predictors was constructed using multivariate logistic regression. Prediction capabilities of each model were assessed with receiver operating characteristic (ROC) curve analysis. Performance of the nomogram was evaluated by its calibration and potential clinical usefulness. RESULTS: For the prediction of good response (GR) and pathologic complete response (pCR), the developed radiomics signature comprising 10 and 7 features, respectively, were significantly associated with the therapeutic response to nCRT. The nomogram incorporating the radiomics signature and important clinical predictors (CEA and CA19-9 for predicting GR; CEA, posttreatment length and posttreatment thickness for predicting pCR) achieved favorable prediction efficacy, with AUCs of 0.918 (95% confidence interval [CI]: 0.867-0.971, Sen = 0.972, Spe = 0.828) and 0.944 (95% CI: 0.891-0.997, Sen = 0.943, Spe = 0.828) in the training and validation cohort for predicting GR, respectively; with AUCs of 0.959 (95% CI: 0.927-0.991, Sen = 1.000, Spe = 0.833) and 0.912 (95% CI: 0.843-0.982, Sen = 1.000, Spe = 0.815) in the training and validation cohort for predicting pCR, respectively. Decision curve analysis confirmed potential clinical usefulness of our nomogram. CONCLUSIONS: This study demonstrated that the MRI-based radiomics nomogram is predictive of response to nCRT and can be considered as a promising tool for facilitating treatment decision-making for patients with LARC.

Radiomics signature as a new biomarker for preoperative prediction of neoadjuvant chemoradiotherapy response in locally advanced rectal cancer.

PURPOSE: Whether radiomics methods are useful in prediction of therapeutic response to neoadjuvant chemoradiotherapy (nCRT) is unclear. This study aimed to investigate multiple magnetic resonance imaging (MRI) sequence-based radiomics methods in evaluating therapeutic response to nCRT in patients with locally advanced rectal cancer (LARC). METHODS: This retrospective study enrolled patients with LARC (06/2014-08/2017) and divided them into nCRT-sensitive and nCRT-resistant groups according to postoperative tumor regression grading results. Radiomics features from preoperative MRI were extracted, followed by dimension reduction using the minimum redundancy maximum relevance filter. Three machine-learning classifiers and an ensemble classifier were used for therapeutic response prediction. Radiomics nomogram incorporating clinical parameters were constructed using logistic regression. The receiver operating characteristic (ROC), decision curves analysis (DCA) and calibration curves were also plotted to evaluate the prediction performance. RESULTS: The machine learning classifiers showed good prediction performance for therapeutic responses in LARC patients (n=189). The ROC curve showed satisfying performance (area under the curve [AUC], 0.830; specificity, 0.794; sensitivity, 0.815) in the validation group. The radiomics signature included 30 imaging features derived from axial T1-weighted imaging with contrast and sagittal T2-weighted imaging and exhibited good predictive power for nCRT. A radiomics nomogram integrating carcinoembryonic antigen levels and tumor diameter showed excellent performance with an AUC of 0.949 (95% confidence interval, 0.892-0.997; specificity, 0.909; sensitivity, 0.879) in the validation group. DCA confirmed the clinical usefulness of the nomogram model. CONCLUSION: The radiomics method using multiple MRI sequences can be used to achieve individualized prediction of nCRT in patients with LARC before treatment.

Preoperative prediction of peritoneal metastasis in colorectal cancer using a clinical-radiomics model.

PURPOSE: To establish and validate a combined clinical-radiomics model for preoperative prediction of synchronous peritoneal metastasis (PM) in patients with colorectal cancer (CRC). METHOD: We enrolled 779 patients (585 in the training set: 553 with nonmetastasis (NM) and 32 with PM; 194 in the validation set: 184 with NM and 10 with PM) with clinicopathologically confirmed CRC. The significant clinical risk factors were used to build the clinical model; the least absolute shrinkage and selection operator (LASSO) algorithm was adopted to construct a radiomics signature, which included imaging features of the primary lesion and the largest peripheral lymph node, and stepwise logistic regression was applied to select the significant variables to develop the clinical-radiomics model. We used the Akaike information criterion (AIC) and receiver operating characteristic analysis to compare the goodness of fit and the prediction performance of the three models respectively. An independent validation cohort, containing 139 consecutive patients from February to September 2018, was used to evaluate the performance of the optimal model. RESULTS: Among the three models, the clinical-radiomics model (AUC = 0.855; AIC = 1043.2) was identified as the optimal model, with the maximum AUC value and the minimum AIC value (the clinical-only model: AUC = 0.771, AIC = 1277.7; the radiomics-only model: AUC = 0.764, AIC = 1280.5). The clinical-radiomics model also showed good discrimination in both the validation cohort (AUC = 0.793) and the independent validation cohort (AUC = 0.781). CONCLUSIONS: The present study proposes a clinical-radiomics model created with the CT-based radiomics signature and key clinical features that can potentially be applied in the individual preoperative prediction of synchronous PM for CRC patients.

Regulation of flowering time in chrysanthemum by the R2R3 MYB transcription factor CmMYB2 is associated with changes in gibberellin metabolism.

The switch from vegetative growth to reproductive growth is a key event in the development of a plant. Here, the product of the chrysanthemum gene CmMYB2, an R2R3 MYB transcription factor that is localized in the nucleus, was shown to be a component of the switching mechanism. Plants engineered to overexpress CmMYB2 flowered earlier than did wild-type plants, while those in which CmMYB2 was suppressed flowered later. In both the overexpression and RNAi knockdown plants, a number of genes encoding proteins involved in gibberellin synthesis or signaling, as well as in the response to photoperiod, were transcribed at a level that differed from that in the wild type. Both yeast two-hybrid and bimolecular fluorescence complementation assays revealed that CmMYB2 interacts with CmBBX24, a zinc-finger transcription factor known to regulate flowering by its influence on gibberellin synthesis.

CmMYB8 encodes an R2R3 MYB transcription factor which represses lignin and flavonoid synthesis in chrysanthemum.

R2R3-MYB transcription factors are important regulators of the growth and development of plants. Here, CmMYB8 a chrysanthemum gene encoding an R2R3-MYB transcription factor, was isolated and functionally characterized. The gene was transcribed throughout the plant, but most strongly in the stem. When CmMYB8 was over-expressed, a number of genes encoding components of lignin synthesis were down-regulated, and the plants' lignin content was reduced. The composition of the lignin in the transgenic plants was also altered, and its S/G ratio was reduced. A further consequence of the over-expression of CmMYB8 was to lessen the transcript abundance of key genes involved in flavonoid synthesis, resulting in a reduced accumulation of flavonoids. The indication is that the CmMYB8 protein participates in the negative regulation of both lignin and flavonoid synthesis.

Chrysanthemum (Chrysanthemum morifolium) CmICE2 conferred freezing tolerance in Arabidopsis.

Genes of the ICE (Inducer of CBF Expression) family play a key role in cold and freezing stresses response via the CBF regulatory pathway. In this work, we identified the ICE family gene, CmICE2, from Chrysanthemum morifolium 'Jinba'. CmICE2 encodes a 451-amino acid protein with a conserved nuclear localization domain, a bHLH domain and ACT domain. CmICE2 is expressed in abundance in leaves and flowers, and the expression of CmICE2 is induced by freezing and drought stresses. CmICE2 localized to the nucleus, and has transcriptional activity in yeast cells. After a 24-hour 4 °C acclimation, Arabidopsis plants overexpressing CmICE2 were more tolerant to freezing stress (-9 °C for 6 h) than the Col-0. When exposed to -9 °C for 6 h, the expression levels of genes such as AtCBF1, AtCBF2, AtCBF4, AtCOR 6.6A, AtCOR 414 and AtKIN1 were up-regulated significantly in CmICE2 overexpression plant lines compared to wild type. The proline contents, activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were also increased in plants overexpressing CmICE2. In summary, CmICE2 confers to plant response to freezing stress.

Methylene Blue-Based Near-Infrared Fluorescence Imaging for Breast Cancer Visualization in Resected Human Tissues.

Breast-conserving surgery is facing the challenge of objective tumor margin identification intraoperatively. Near-infrared fluorescence imaging would be an ideal approach to visualize tumor margins during surgeries. In this preliminary study, the feasibility of methylene blue-based near-infrared fluorescence imaging technique for breast cancer detection was assessed in resected human breast specimens after breast cancer surgeries. Thirty patients with breast cancer scheduled for surgical treatment were enrolled, including 10 patients with preoperative chemotherapy and 20 patients without. Each of them received an injection of 1 mg/kg methylene blue intravenously 3 hours before the surgery. Then, a home-developed methylene blue-specific near-infrared fluorescence imaging system was employed to image the resected breast tissues and identify the tumor by the fluorescence contrast. Specimens were taken for pathological examinations as the reference. There were no severe adverse events attributable to methylene blue. Of 20 patients, who did not receive preoperative chemotherapy, 16 exhibited fluorescent contrast on their resected tissues (signal-to-background ratio: 1.94 ± 0.71). In contrast, tumors were identified in 3 of 10 specimens from patients who underwent preoperative chemotherapy (signal-to-background ratio: 1.63 ± 0.38). A total of 35 tissues were sampled from 30 specimens. Besides 30 tumor samples, 5 more suspicious samples with fluorescence signal were confirmed to be benign hemorrhagic tissues. Therefore, a sensitivity of 0.63 and a positive predictive value of 0.79 were achieved by the methylene blue fluorescence imaging strategy. Here, we demonstrate the feasibility of using methylene blue fluorescence imaging to identify breast cancer. Preoperative chemotherapy had an impact on imaging effect, which may reduce the detection rate. After all, methylene blue fluorescence imaging has great potential to be used into breast-conserving surgery for tumor-positive margins detection, but further clinical trial study is needed ( http://www.chictr.org.cn/ Clinical Trial Registry ID: ChiCTR1800015400, Near-infrared fluorescence imaging applied in breast cancer identification with methylene blue).

Morphological, Genome and Gene Expression Changes in Newly Induced Autopolyploid Chrysanthemum lavandulifolium (Fisch. ex Trautv.) Makino.

Autopolyploidy is widespread in higher plants and plays an important role in the process of evolution. The present study successfully induced autotetraploidys from Chrysanthemum lavandulifolium by colchicine. The plant morphology, genomic, transcriptomic, and epigenetic changes between tetraploid and diploid plants were investigated. Ligulate flower, tubular flower and leaves of tetraploid plants were greater than those of the diploid plants. Compared with diploid plants, the genome changed as a consequence of polyploidization in tetraploid plants, namely, 1.1% lost fragments and 1.6% novel fragments occurred. In addition, DNA methylation increased after genome doubling in tetraploid plants. Among 485 common transcript-derived fragments (TDFs), which existed in tetraploid and diploid progenitors, 62 fragments were detected as differentially expressed TDFs, 6.8% of TDFs exhibited up-regulated gene expression in the tetraploid plants and 6.0% exhibited down-regulation. The present study provides a reference for further studying the autopolyploidization role in the evolution of C. lavandulifolium. In conclusion, the autopolyploid C. lavandulifolium showed a global change in morphology, genome and gene expression compared with corresponding diploid.

Chrysanthemum transcription factor CmLBD1 direct lateral root formation in Arabidopsis thaliana.

The plant-specific LATERAL ORGAN BOUNDARIES DOMAIN (LBD) genes are important regulators of growth and development. Here, a chrysanthemum class I LBD transcription factor gene, designated CmLBD1, was isolated and its function verified. CmLBD1 was transcribed in both the root and stem, but not in the leaf. The gene responded to auxin and was shown to participate in the process of adventitious root primordium formation. Its heterologous expression in Arabidopsis thaliana increased the number of lateral roots formed. When provided with exogenous auxin, lateral root emergence was promoted. CmLBD1 expression also favored callus formation from A. thaliana root explants in the absence of exogenously supplied phytohormones. In planta, CmLBD1 probably acts as a positive regulator of the response to auxin fluctuations and connects auxin signaling with lateral root formation.

Phylogenetic and transcription analysis of chrysanthemum WRKY transcription factors.

WRKY transcription factors are known to function in a number of plant processes. Here we have characterized 15 WRKY family genes of the important ornamental species chrysanthemum (Chrysanthemum morifolium). A total of 15 distinct sequences were isolated; initially internal fragments were amplified based on transcriptomic sequence, and then the full length cDNAs were obtained using RACE (rapid amplification of cDNA ends) PCR. The transcription of these 15 genes in response to a variety of phytohormone treatments and both biotic and abiotic stresses was characterized. Some of the genes behaved as would be predicted based on their homology with Arabidopsis thaliana WRKY genes, but others showed divergent behavior.