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Purpose: Sleep disorders are prevalent and often neglected among breast cancer patients. This study aimed to identify the association among perceived stress, loneliness, resilience and sleep disorders, and to further explore whether resilience could be a moderator in the association between perceived stress, loneliness and sleep disorders among Chinese female breast cancer patients.Methods: A cross-sectional study was conducted at a tertiary hospital in Anshan, China from October 2019 to October 2020. 492 valid questionnaires were collected. Patients were asked in response to the questionnaires including the Pittsburgh Sleep Quality Index, Perceived Stress Scale-10, the Three-Item Loneliness Scale and Resilience Scale-14. The association among perceived stress, loneliness, resilience and perceived stress/loneliness × resilience interaction with sleep disorders were examined by hierarchical multiple regression analysis. The interaction was visualized by using simple slope analysis. Results: In our study, 36.58% of the female breast cancer patients reported sleep disorders. Perceived stress and loneliness were related to sleep disorders. Resilience could moderate the relationship between them and sleep disorders. When resilience was higher, perceived stress and loneliness had a weaker impact on sleep disorders.Conclusions: There was a high prevalence of sleep disorders and this study implied an adverse effect of perceived stress, loneliness on the sleep quality. However, resilience could moderate the association between perceived stress, loneliness and sleep disorders. More positive psychological interventions should be integrated into the prevention of sleep disorders among cancer patients.

Monopolar spindle 1 (MPS1), which plays a critical role in somatic mitosis, has also been revealed to be essential for meiosis I in oocytes. Spermatogenesis is an important process involving successive mitosis and meiosis, but the function of MPS1 in spermatogenesis remains unclear. Here, we generated Mps1 conditional knockout mice and found that Ddx4-cre-driven loss of Mps1 in male mice resulted in depletion of undifferentiated spermatogonial cells and subsequently of differentiated spermatogonia and spermatocytes. In addition, Stra8-cre-driven ablation of Mps1 in male mice led to germ cell loss and fertility reduction. Spermatocytes lacking Mps1 have blocked at the zygotene-to-pachytene transition in the prophase of meiosis I, which may be due to decreased H2B ubiquitination level mediated by MDM2. And the expression of many meiotic genes was decreased, while that of apoptotic genes was increased. Moreover, we also detected increased apoptosis in spermatocytes with Mps1 knockout, which may have been the reason why germ cells were lost. Taken together, our findings indicate that MPS1 is required for mitosis of gonocytes and spermatogonia, differentiation of undifferentiated spermatogonia, and progression of meiosis I in spermatocytes.

DG integration reduces the selectivity and sensitivity of grid relay protection. A new control algorithm is proposed. It shows that the negative sequence current will not be affected by DG when the DG is designed as a symmetric three-phase current source. In this case, the negative sequence characteristic can be utilized for grid protection during short-circuit faults. If DGs maximum power capacity is restricted to be lower than total load capacity, DG terminal line-voltage and the negative sequence voltage can be used as the criteria for islanding detection. Then it is possible to cutoff DG in order to fulfill the reclosing requirement. A complicated simulation system is designed using PSCAD/EMTDC program. Different short-circuit faults are simulated to verify the proposals. The test results confirm well with the conclusions.

Astronomical telescopes with increasingly large apertures are required to upgrade the limit of diffraction and collect the light efficiently for the purpose of observing fainter and more remote objects with higher angular resolution. However, it is universally believed that traditional techniques of manufacturing, polishing and measuring large glass mirrors will soon face some practical challenges. Therefore, 10-m class or larger ground-based telescopes will need to employ arrays of several smaller segments to assemble into a large primary mirror. For a telescope with segmented mirrors, the piston errors between segments must be adjusted to nearly zero according to the requirements in order to be integrated into a single optical surface, which is known as co-phasing. One of the current co-phasing techniques, which has been successfully applied to Keck telescopes, employs an integration of edge sensors to detect the mirror shapes in real time with an optical phasing sensor to offer zero references for these sensors regularly. Another technique is demonstrated by use of a pyramid wavefront sensor (PWFS) to align and co-phase segmented mirrors in an active control close-loop with a single measurement. The co-phased best flat positions of segments are used as the zero references in order to measure the interaction matrix between the PWFS and the segmented mirrors. So it must be addressed that how the zero co-phasing reference is calibrated with high precision in a large capture range on the issues of co-phasing segmented mirrors. The current methods either lack accuracies, or just measure piston errors correctly in a small range. In order to solve the problem, a zero co-phasing reference calibration method based on dispersed interferogram is proposed. Specifically, the idea of the method is to define an appropriate cost function which is used to evaluate the piston errors between segments. Then it will be easy to determine the zero co-phasing reference position while all the cost function values are calculated based on the dispersed interferogram data with different piston errors inside the capture range. The proposed cost function is defined as the sum of the ratios of the second peak to the third peak of each of the columns of the two-dimensional dispersed interferogram, whose intensity distribution is along the dispersion direction. The precision and dynamic range of the method are analyzed theoretically and studied by simulations. Furthermore, the optical experiment is set up to demonstrate the efficacy of the method. In the experiment a scanning procedure is applied to one mirror and the dispersed interferograms between two mirrors with different piston errors are obtained. And then, the cost functions of these dispersed interferograms are computed through which the zero co-phasing reference position is located. The experimental results prove that the zero co-phasing reference between two mirrors can be calibrated within an accuracy of about 10 nm by making use of the proposed method. In addition, the novel method solves the problem of 2 ambiguity. Besides its sub-millimeter level wide capture range, this new co-phasing detecting method provides a helpful reference for relevant studies.

For the Fizeau optical interferometric telescope system, the co-phasing detection of piston errors between sub-apertures plays an important role in realizing the high resolution of system. In this paper, the relationship between piston error and the main peak displacement of monochromatic interferogram of two sub-aperture system is analyzed based on physical principles, then the piston error detecting method is developed and clarified based on their linear relationship in the range of one wavelength. Furthermore, an innovative co-phasing detecting method based on grating dispersed interferogram with bandwidth light source is proposed, and its feasibility, detecting precision and dynamic range are analyzed in theory and studied in simulation. The results prove that with this method, the piston error between the two sub-apertures of the system can be soundly detected and its measuring error is less than 20 nm while the piston error is not more than 50 μm. In addition, the novel method solves the problems of 2π ambiguity and direction determination that might exist within some other detecting methods. Besides its millimeter level dynamic range, this new co-phasing detecting method provides a new way and an effective reference for in-depth research of co-phasing detecting techniques.