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The emerging technology of rotating synthetic aperture (RSA) presents a promising solution for the development of lightweight, large-aperture, and high-resolution optical remote sensing systems in geostationary orbit. However, the rectangular shape of the primary mirror and the distinctive imaging mechanism involving the continuous rotation of the mirror lead to a pronounced decline in image resolution along the shorter side of the rectangle compared to the longer side. The resolution also exhibits periodic time-varying characteristics. To address these limitations and enhance image quality, we begin by analyzing the imaging mechanism of the RSA system. Subsequently, we propose a single-image super-resolution method that utilizes a rotated varied-size window attention mechanism instead of full attention, based on the Vision Transformer architecture. We employ a two-stage training methodology for the network, where we pre-train it on images masked with stripe-shaped masks along the shorter side of the rectangular pupil. Following that, we fine-tune the network using unmasked images. Through the strip-wise mask sampling strategy, this two-stage training approach effectively circumvents the interference of lower confidence (clarity) information and outperforms training the network from scratch using the unmasked degraded images. Our digital simulation and semi-physical imaging experiments demonstrate that the proposed method achieves satisfactory performance. This work establishes a valuable reference for future space applications of the RSA system. [ABSTRACT FROM AUTHOR]

Background: This study was conducted to evaluate the effects of different levels of citric acid (CA) on the growth performance, nutrient digestibility and gastrointestinal pH of weaned piglets. Methods: A total of 120 weaned piglets with an initial BW of 7.15±0.01 kg, were randomly divided into four groups including control treatment each with three replicates of 10 piglets each. Each group was supplemented with 0.5% (control group), 1%, 1.5% and 2% CA in the basal diet, respectively. Result: The results showed that the average daily feed intake (ADFI) and average daily gain (ADG) of added 1% CA group were significantly higher than that of 0.5% group (P<0.05). Dietary CA significantly improved the utilization rates of crude protein, calcium and phosphorus (P<0.05), while there was no significant difference between adding 1% and 1.5% CA (P>0.05). Compared with the control group, adding CA effectively reduced the pH of the stomach, duodenum jejunum and ileum contents and adding 2% CA were significantly lower than those in other groups (P<0.05). Therefore, the addition of 1.0% CA in the diets of weaned piglets is suitable. [ABSTRACT FROM AUTHOR]

Background: Heterogeneity of leukemia-initiating cells (LICs) is a major obstacle in acute myeloid leukemia (AML) therapy. Accumulated evidence indicates that the coexistence of multiple types of LICs with different pathogenicity in the same individual is a common feature in AML. However, the functional heterogeneity including the drug response of coexistent LICs remains unclear. Therefore, this study aimed to clarify the intra-heterogeneity in LICs that can help predict leukemia behavior and develop more effective treatments., Methods: Spleen cells from the primary Setd2 -/- -AML mouse were transplanted into C57BL/6 recipient mice to generate a transplantable model. Flow cytometry was used to analyze the immunophenotype of the leukemic mice. Whole-genome sequencing was conducted to detect secondary hits responsible for leukemia transformation. A serial transplantation assay was used to determine the self-renewal potential of Setd2 -/- -AML cells. A limiting-dilution assay was performed to identify the LIC frequency in different subsets of leukemia cells. Bulk and single-cell RNA sequencing were performed to analyze the transcriptional heterogeneity of LICs. Small molecular inhibitor screening and in vivo drug treatment were employed to clarify the difference in drug response between the different subsets of LICs., Results: In this study, we observed an aged Setd2 -/- mouse developing AML with co-mutation of Nras G12S and Braf K520E . Further investigation identified two types of LICs residing in the c-Kit + B220 + Mac-1 - and c-Kit + B220 + Mac-1 + subsets, respectively. In vivo transplantation assay disclosed the heterogeneity in differentiation between the coexistent LICs. Besides, an intrinsic doxorubicin-resistant transcriptional signature was uncovered in c-Kit + B220 + Mac-1 + cells. Indeed, doxorubicin plus cytarabine (DA), the standard chemotherapeutic regimen used in AML treatment, could specifically kill c-Kit + B220 + Mac-1 - cells, but it hardly affected c-Kit + B220 + Mac-1 + cells. Transcriptome analysis unveiled a higher activation of RAS downstream signaling pathways in c-Kit + B220 + Mac-1 + cells than in c-Kit + B220 + Mac-1 - cells. Combined treatment with DA and RAS pathway inhibitors killed both c-Kit + B220 + Mac-1 - and c-Kit + B220 + Mac-1 + cells and attenuated disease progression., Conclusions: This study identified two cell subsets enriched for LICs in murine Setd2 -/- -AML and disclosed the transcriptional and functional heterogeneity of LICs, revealing that the coexistence of different types of LICs in this model brings about diverse drug response., (© 2021 The Authors. Cancer Communications published by John Wiley & Sons Australia, Ltd. on behalf of Sun Yat-sen University Cancer Center.)