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During yeast dough fermentation, such as the high-sucrose bread-making process, the yeast cells are subjected to considerable osmotic stress, resulting in poor outcomes. Invertase is important for catalyzing the irreversible hydrolysis of sucrose to free glucose and fructose, and decreasing the catalytic activity of the invertase may reduce the glucose osmotic stress on the yeast. In this study, we performed structural design and site-directed mutagenesis (SDM) on the Saccharomyces cerevisiae invertase (ScInV) in an Escherichia coli expression system to study the catalytic activity of ScInV mutants in vitro. In addition, we generated the same mutation sites in the yeast endogenous genome and tested their invertase activity in yeast and dough fermentation ability. Our results indicated that appropriately reduced invertase activity of yeast ScInV can enhance dough fermentation activity under high-sucrose conditions by 52%. Our systems have greatly accelerated the engineering of yeast endogenous enzymes both in vitro and in yeast, and shed light on future metabolic engineering of yeast.

The Social Responsibility (SR) commitments of Higher Education Institutions (HEIs) alongside their long-standing functions of teaching and research have been recognized in literature. However, University Social Responsibility (USR) remains a relatively unexplored topic, especially in the post-conflict societies of the Great Lakes Region of East Africa (GLREA). The main objective of this paper is to document USR best practices, challenges and opportunities in GLREA universities. To reach this objective, a search was conducted in the major academic databases, where ten studies out of 93 found from 2000 to 2020 were included for review. Additionally, universities' website materials, particularly Vision and Mission Statements (VMS) were considered to complement the review in a well established sense of USR in GLREA universities. A narrative review was conducted because quantitative data were not feasible due to a significant level of heterogeneity between the included studies. The overall findings indicated that the scholarship of engagement in the regional context is not a luxury of HEIs as it is in many western universities, but rather a necessity in countries which are still undergoing the early stages of reconstruction. Specifically, the results obtained were twofold: First, the integrated SR in GLREA universities is an emerging agenda, despite its potential for growth. Second, the development of USR in the GLREA is connected to and influenced by the history of African Higher Education, and the institutional traces of that history's influence can be found in GLREA. Finally, recommendations for USR practitioners are given, and a conclusion is drawn.

Brassinosteroids (BRs) are a class of polyhydroxylated steroidal phytohormones and essential for plant growth and development. Rice BRASSINOSTEROID-INSENSITIVE1 (BRI1)-ASSOCIATED RECEPTOR KINASES (OsBAKs) are plasma membrane (PM)-localized receptor kinases, belonging to the subfamily of leucine-rich repeat (LRR) receptor kinases. In Arabidopsis, BRs induce the formation of BRI1-BAK1 heterodimer complex and transmit the signal cascade to the BRASSINAZOLE RESISTANT1/bri1-EMS-SUPPRESSOR1 (BZR1/BES1) to regulate BR signaling. In rice, we found that OsBZR1 binds directly to the promoter of OsBAK2, not OsBAK1, and represses the expression of OsBAK2 to form a BR feedback inhibition loop. Additionally, the phosphorylation of OsBZR1 by OsGSK3 reduced its binding activity to OsBAK2 promoter. The osbak2 displays a typical BR deficient phenotype and negatively modulates the accumulation of OsBZR1. Interestingly, the grain length of osbak2 mutant was increased whereas the cr-osbak2/cr-osbzr1 double mutant restored the reduced grain length of cr-osbzr1 mutant, implying that the increased grain length of osbak2 may be due to the rice SERKs-dependent pathway. Our study reveals a novel mechanism of OsBAK2 and OsBZR1 engaging in a negative feedback loop to maintain rice BR homeostasis, facilitating to a deeper understanding of BR signaling network and grain length regulation in rice.

This letter proposes a new method for focusing ground maneuvering targets and estimating the motion parameters with a synthetic aperture radar (SAR) system. In this method, the Hough transform is applied to estimate the cross-track velocity from the slope of the range walk (RW) trajectory, and the RW and Doppler centroid shift are compensated. The second-order Keystone transform is performed to correct the additional range curve caused by the along-track velocity and cross-track acceleration. Then, we adopt the adaptive polynomial Fourier transform to estimate the second- and third-order Doppler parameters from a 1-D parameter interval, and the corresponding motion parameters are calculated. Finally, the moving target is well focused after the motion parameters compensation because the second- and third-order Doppler parameters are efficiently eliminated. Both the simulated and real data processing results are presented to demonstrate the validity of the proposed algorithm.

In this letter, a new technique based on genetic algorithm and support vector machine (GA-SVM) is proposed to effectively estimate the 3-D deformations of the earth's surface by integrating sparse global navigation satellite system (GNSS) deformation measurements and interferometric synthetic aperture radar (InSAR) maps. The genetic algorithm (GA) is used to search the optimal supported vector machine (SVM) control parameters, considering the control parameters have an important influence on the prediction. Based on advanced machine learning theory, the proposed method has at least two main advantages over traditional methods: 1) it does not need to preinterpolate the displacements of GNSS points, and 2) it does not need to estimate the variance components of GNSS and InSAR point by point. Both the simulated and real experiments are implemented to prove the effectiveness of GA-SVM. In the real case of the Los Angeles, the root mean square errors of GA-SVM at 14 checkpoints are 7.92, 2.05, and 5.43 mm/a in the east-west, north-south, and vertical directions, respectively.

Spaceborne synthetic aperture radar (SAR) can operate at various modes, including stripmap mode, spotlight mode, sliding spotlight mode, and Terrain observation by progressive scans (TOPS) mode. These four imaging modes can be regarded as unified, differing in rotation-center ranges. To uniformly focus the data of these four imaging modes in real-time, this article proposes a real-time unified focusing algorithm (RT-UFA) for the multi-mode SAR via azimuth sub-aperture complex-valued image combining and scaling. The imaging processing can be performed while the data are being recorded. In the first stage of imaging, sub-aperture complex-valued images with relative low-resolution can be obtained by the cascade of the extended chirp scaling (ECS) and azimuth dechirp. Then, these complex-valued images are coherently combined by shifting the integer number of pixels, and thus the full-resolution image of all the recorded data can be obtained. The azimuth scaling and the pixels shifting in the RT-UFA are analyzed in detail. Simulation and SAR data results are presented to validate the analysis and RT-UFA.