We generated a global genetic interaction network for
Saccharomyces cerevisiae
, constructing over 23 million double mutants, identifying ~550,000 negative and ~350,000 positive genetic interactions. ...This comprehensive network maps genetic interactions for essential gene pairs, highlighting essential genes as densely connected hubs. Genetic interaction profiles enabled assembly of a hierarchical model of cell function, including modules corresponding to protein complexes and pathways, biological processes, and cellular compartments. Negative interactions connected functionally related genes, mapped core bioprocesses, and identified pleiotropic genes, whereas positive interactions often mapped general regulatory connections among gene pairs, rather than shared functionality. The global network illustrates how coherent sets of genetic interactions connect protein complex and pathway modules to map a functional wiring diagram of the cell.
Potassium channel tetramerization domain containing 1 (KCTD1) contains a BTB domain, which can facilitate protein-protein interactions that may be involved in the regulation of signaling pathways. ...Here we describe an expression and purification system that can provide a significant amount of recombinant KCTD1 from
Escherichia coli
. The cDNA encoding human KCTD1 was amplified and cloned into the expression vector pET-30a(+). The recombinant protein was expressed in
E. coli
BL21(DE3) cells and subsequently purified using affinity chromatography. To confirm that KCTD1 was correctly expressed and folded, the molecular weight and conformation were analyzed using mass spectroscopy, Western blot, and circular dichroism. Optimizing KCTD1 expression and investigating its secondary structure will provide valuable information for future structural and functional studies of KCTD1 and KCTD family proteins.
Porcine reproductive and respiratory syndrome (PRRS) is considered one of the most important infectious diseases to affect the swine industry and characterized by reproductive failure in late term ...gestation in sows and respiratory disease in pigs of all ages. The GP5a gene, encoding RNA-dependent RNA polymerase, is generally regarded as fairly conserved when compared to other viral proteins. It plays an important role in the process of duplication and transcription carried out by Porcine reproductive and respiratory syndrome virus (PRRSV). We firstly expressed and purified the GP5a protein of PRRSV. This provides a good method for the purification of expressed proteins and the preparation of the corresponding antibodies.
Myoclonus dystonia syndrome is a rare movement disorder featured by myoclonic jerks and dystonia. We identified here a point mutation in ε-sarcoglycan gene exon 6 associating with inherited myoclonus ...dystonia syndrome in a Chinese Han family. The mutation identified induces a stop codon and terminates the transcription of ε-sarcoglycan mRNA. This in turn results in a large truncation of ε-sarcoglycan protein. The further investigation is required to understand physiological and pathological functions of ε-sarcoglycan.
Q42; The availability of a well-characterized animal brain tumor model will play an important role in identifying treatments for human brain tumors. Wistar rats bearing 9L glioma cells can develop ...solid, well-circumcised tumors, and may be a useful animal model for the evaluation of various therapeutic approaches for gliosarcomas. In this study, the 9L/Wistar rat glioma model was produced by intracerebral implantation of 9LLUC glioma cells syngenic to Fischer 344 (F344) rats. Bioluminescence imaging showed that tumors progressively grew from day 7 to day 21 in 9LLUC/F344 rats, and tumor regression was found in some 9LLUC/Wistar rats. Hematoxylin-eosin staining verified that intracranial tumors were gliomas. Immunohistochemistry results demonstrated that no CD4- and CD8-positive cells were found in the syngeneic 9LLUC/F344 model. However, many infiltrating CD4- and CD8-positive cells were observed within the tumors of the 9LLUC/Wistar model. Our data suggests that compared with 9L/F344 rats, 9L glioma Wistar rats may not be suitable for evaluating brain glioma immunotherapies, even though the model induced an immune response and exhibited tumor regression.
The availability of a well-characterized animal brain tumor model will play an important role in identifying treatments for human brain tumors. Wistar rats bearing 9L glioma cells can develop solid, ...well-circumcised tumors, and may be a useful animal model for the evaluation of various therapeutic approaches for gliosarcomas. In this study, the 9L/Wistar rat glioma model was produced by intracerebral implantation of 9L(LUC) glioma cells syngenic to Fischer 344 (F344) rats. Bioluminescence imaging showed that tumors progressively grew from day 7 to day 21 in 9L(LUC)/F344 rats, and tumor regression was found in some 9L(LUC)/Wistar rats. Hematoxylin-eosin staining verified that intracranial tumors were gliomas. Immunohistochemistry results demonstrated that no CD4- and CD8-positive cells were found in the syngeneic 9L(LUC)/F344 model. However, many infiltrating CD4- and CD8-positive cells were observed within the tumors of the 9L(LUC)/Wistar model. Our data suggests that compared with 9L/F344 rats, 9L glioma Wistar rats may not be suitable for evaluating brain glioma immunotherapies, even though the model induced an immune response and exhibited tumor regression.
With the continuous expansion of the power system and the construction of the series compensator devices in Northwest China, interactions between the generators and the power grid become more ...complicated while the problem of subsynchronous resonance (SSR) is more prominent. To deal with this problem, a controller named subsynchronous resonance dynamic suppressor (SSRDS) based on voltage source converter (VSC) for damping SSR of multi-generator system is proposed. Meanwhile, this study also presents an analysis of the control strategy of SSRDS and the method of connecting the power grid. The damping characteristics of SSRDS and the interaction between SSRDS and grid are analyzed by the complex torque coefficient method. A detailed electro-magnetic transient simulation model based on the expansion topology of future Jinjie Power Plant in northern China is established to verify the analytical results. The results show that the proposed control strategy can effectively suppress SSR in the system of six generators and six modes through one-to-many control method. Compared to the traditional thyristor controlled reactor-subsynchronous damping controller (TCR-SSDC), the controller can achieve the same effect with a smaller capacity, a faster response and less harmonic pollution.
A doubly-fed induction generator (DFIG) based method for improving the inter-area oscillation damping by using fast active power modulation is proposed in this paper. Firstly, the detailed model of ...DFIGs is introduced. Then the design flowchart of the DFIG damping controller is presented by analogy to the power system stabilizer (PSS). The method of small signal stability analysis to the power system is given. Though those methods, the damping effectiveness of the proposed controller is analyzed theoretically by calculating the eigenvalues of the inter-area oscillation domain mode in the 4-machine 2-area system. The inter-area oscillations in the system with and without the additional damping controller is further compared though the transient simulation. Both the theoretical and simulation results show that the addition of the DFIG damping controller can effectively improve the damping of the system and suppress the inter-area oscillation.
SSO Analysis of D-PMSGs-based Wind Farm considering the PLL Wu, Xiaofang; Zeng, Feng; Yuan, Xiaotian ...
2019 IEEE 8th International Conference on Advanced Power System Automation and Protection (APAP),
2019-Oct.-21
Conference Proceeding
With the large-scale access of renewable energy, the problem of sub-synchronous oscillation (SSO) caused by the interaction between the direct-drive permanent magnetic synchronous generators ...(D-PMSGs)-based wind farm and weak AC grid has attracted people's attention. Focusing on this topic, the study presents an analysis of the SSO mechanism by establishing the double input and double output transfer function of the d axis and q axis currents. Because of the dynamic characteristics of PLL and the existence of grid-connected inductance, d axis and q axis current transfer functions are coupled and asymmetric, which introduced positive feedback into the closed-loop negative feedback system of current transfer functions. The positive feedback is related to controller parameters, PLL parameters, grid-connected inductance and operation conditions. The combination of some parameters may cause oscillation or instability of the system. In this paper, the root locus method is used to analyze the influence of these parameters on the stability of the system. Finally, eigenvalue analysis and electromagnetic transient simulation are used to verify the correctness of the method.
Based on a 3D finite element model, one adjustable speed permanent magnet coupling(ASPMC) was studied. By analyzing finite element simulation results, some basic conclusions for adjustable-speed ...permanent magnet couplings' design and optimization have been presented. Simulate and analyze the electromagnetic field and eddy distributions of prototype at rated operating station. When the prototype's performance is optimum, confirm the permanent magnet's thickness and width, the copper disc's thickness and outer diameter. Besides, the relationship and regularity between the outer diameter of the coupling and transmitted power has been proposed. The prototype's torque transmission capability over the full range of slip speed for different airgap settings and process for speed adjustment are given. Manufacture a prototype and build a experimental platform. Through the experimental test, verify the reasonability of the prototype's design and the applicability of the optimizing design method.
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