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With the popularization of smart terminals and multimedia technologies, the video coding standard — H.264/Advanced Video Coding (AVC) and H.265/High Efficiency Video Coding (HEVC) have been unable to meet the needs of various high-definition videos, so the next generation standard —H.266/ Versatile Video Coding (VVC) is under study. In the actual transmission of a video communication channel, rate control plays an important role. However, HEVC rate control based on R-λ model does not adequately take into account the characteristics of the human visual system (HVS). Also, the convergence speed of Least Mean Square (LMS) in HEVC is too slow. In this paper, an improved R-λ(Lambda) rate control model based on joint spatial-temporal domain information and HVS characteristics (IRLRC) is established. In this model, the joint spatial-temporal domain information based on gradient information is used to guide bit allocation for frame and CTU level, where the temporal coefficient is corrected adaptively. What’s more, the Broyden Fletcher Goldfarb Shanno (BFGS) algorithm is introduced, which speeds up the convergence of the proposed model. The experimental results have clearly shown that the proposed IRLRC can achieve better coding performance than HEVC, VVC and other models. In particular, the video sequence based on the proposed IRLRC can meet the needs of HVS and achieve higher optimization for subjective quality.

Xinxin Li,1,* Dongming Guo,1,* Lingyu Chu,2 Yiteng Huang,3 Feiran Zhang,1 Wei Li,1 Juntian Chen1 1Department of Gastrointestinal Surgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, People’s Republic of China; 2Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou, People’s Republic of China; 3Department of Health Care Center, The First Affiliated Hospital of Shantou University Medical College, Shantou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Juntian ChenDepartment of Gastrointestinal Surgery, The First Affiliated Hospital of Shantou University Medical College, 57 Changping Road, Shantou 515041, Guangdong Province, People’s Republic of ChinaTel/Fax +86 754 8890 5256Email 13809846668@163.comPurpose: To evaluate the diagnostic value of combining the neutrophil–lymphocyte ratio (NLR), platelet–lymphocyte ratio (PLR) or lymphocyte–monocyte ratio (LMR) with carcinoembryonic antigen (CEA) in patients with colorectal cancer (CRC).Patients and methods: The diagnostic performance of inflammatory makers and CEA was evaluated in cohort 1 (664 patients with CRC, 336 patients with colorectal polyps and 664 healthy controls) and validated in cohort 2 (87 patients with CRC and 87 healthy controls) by using receiver operating characteristic curve analysis.Results: In cohort 1, the NLR, PLR and CEA levels were significantly higher, while the LMR was markedly lower in patients with CRC than in healthy controls. The PLR and LMR were significantly associated with invasion depth and lymph node metastasis. Moreover, significant differences in the PLR and LMR were observed between patients with stage I/II CRC and healthy or polyp controls and those with stage III/IV CRC. Using the NLR, PLR or LMR with CEA resulted in a significantly larger area under the curve (AUC) than any of them used alone. Combining the PLR and LMR with CEA exhibited the best diagnostic value for CRC (AUC=0.892). The AUCs of this combination were 0.864 and 0.783 for distinguishing stage I/II CRC from healthy and polyp controls, respectively. When we used the same cut-off values to assess the diagnostic ability of these markers in cohort 2, similar results were observed, and the PLR, LMR and CEA combination also showed the highest accuracy (AUC=0.936).Conclusion: Combining inflammatory cell ratios with CEA could improve the diagnostic efficacy for CRC patients. The combination of the PLR and LMR with CEA might be a valuable indicator in the early detection and monitoring of CRC patients.Keywords: colorectal cancer, neutrophil–lymphocyte ratio, platelet–lymphocyte ratio, lymphocyte–monocyte ratio, carcinoembryonic antigen, diagnosis

Dark signal is the non-negligible component of the CCD (Charge Coupled Devices) camera noise. The most straightforward way to eliminate dark signal is cooling the CCD chip. Moreover, the dark-signal image correction technique gets the more extensive application because of its lower development costs and better dark-signal correction effect. In this article, two methods for estimating the average of dark signals based on temperature and dark pixels are introduced, as well as the method for estimating the pixel nonuniformity of dark signal and for pixel-level dark signal correction. Experiment results show that the method in this article can achieve higher accuracy in dark-signal correction.

Design-based learning (DBL) is attracting increasing attention for its potential to support informal learning, and as a way to enhance science and technology education at schools. However, related research has not yet considered the emotions children experience during DBL and how these affect the learning process. We report a case study aimed at developing a deeper understanding of children's emotional experience during DBL. In total 9 children (12-13 years old) are involved in this case study. In order to assess children's emotions during DBL lessons we used a self-reporting non-verbal instrument (the emotion card, which adapted from Five Degrees of Happiness Smiley Face Likert) and a verbal instrument (the Geneva Emotion Wheel Questionnaire, which contains 16 emotions). In addition, a group interview probed into the role of children's emotion during DBL. We discuss the methodological challenges exposed in this study, which will need to be addressed in future studies regarding the measurement of children's emotions in DBL.

Short history of the origin and stylistic features of world famous children's bunny 'Miffy' ('Nijntje' in Dutch), with a short biographical sketch of its creator, Dutch graphic artist Dick Bruna (1927 -2017) (Text, both in English and Chinese)