99 research outputs found
Nelinearno upravljanje s unutarnjim modelom za pogon s prekidačkim reluktantnim motorom bez oscilacija momenta
Based on the nonlinear internal-model control (IMC), associated with the suitable commutation strategy, a novel control solution for switched reluctance motor (SRM) is formulated and designed. The commutation strategy uses a definite critical rotor position as commutation point, which reduces the computational burden. The nonlinear IMC-based voltage control scheme for SRM extracts the simplicity of the feedback linearization control and the robustness of IMC structure, which ensures the torque ripple-free and the drive\u27s robustness in spite of the plant-model mismatch disturbances. Some important properties are presented. Simulation results show that the high-performance control for SRM has been achieved.Predloženo je i razrađeno novo rješenje za upravljanje sklopnim reluktantnim motorom (SRM) zasnovano na nelinearnom upravljanju s unutarnjim modelom (IMC) i prikladnoj strategiji komutacije. Strategija komutacije koristi definiranu kritičnu poziciju rotora kao točku komutacije što doprinosi smanjenju računskih zahtjevnosti. Shema za upravljanje naponom SRM-a zasnovana na nelinearnom IMC-u osigurava linearizaciju zatvorenog sustava i robusnost IMC strukture što rezultira ukupnom robusnošću pogona bez oscilacija momenta unatoč nepodudaranju modela smetnji sa stvarnim smetnjama. Opisana su neka važna svojstva ovoga načina upravljanja. Simulacijskim se rezultatima pokazuje visoka kvaliteta upravljanja SRM-a
Fermentation of pretreated corncob hemicellulose hydrolysate to ethanol by Candida shehatae and Saccharomyces cerevisiae
To investigate the effect of unknown fermentation inhibitors in corncob hemicellulose acid hydrolysate processed by pretreatment and detoxification on fermentation, corncob hemicellulose acid hydrolysate and artificially prepared hydrolysate were fermented in parallel by Candida shehatae YHFK-2. The results show that fermentability of corncob hemicellulose acid hydrolysate was better than that of the artificially prepared hydrolysate and scale-up of C. shehatae YHFK-2 fermentation was done, which showed that ethanol production in the fermenter was obviously much more than that in flasks. In addition, C. shehatae YHFK-2 and Saccharomyces cerevisiae W5 were used for mixed fermentation of corncob hemicellulose acid hydrolysate, which was done for exploring the possibility of efficiently increasing ethanol production.Key words: Ethanol, corncob hemicellulose acid hydrolysate, fermentation property, stability, mixed fermentation
Cai and Ge, Nitrogen Contents and Its Distribution
Abstract: The nitrogen content of sugar beet plant was significantly positive correlated with nitrogen amount used. At the beginning of beet growing, the distribution of nitrogen was mainly in leaves, but later the distribution rate of nitrogen increased in roots. However, the distribution rate of nitrogen in leaves was still on high level when treated with high amount of nitrogen, which would be against the accumulation of sugar. The contents of phosphorous and potassium of beet plant were also significantly positive correlated with nitrogen amount used, and nitrogen has obvious interaction effect with phosphorus and potassium
Purification, characterization and probiotic proliferation effect of exopolysaccharides produced by Lactiplantibacillus plantarum HDC-01 isolated from sauerkraut
In this study, an exopolysaccharide (EPS)-producing strain of Lactiplantibacillus plantarum HDC-01 was isolated from sauerkraut, and the structure, properties and biological activity of the studied EPS were assessed. The molecular weight of the isolated EPS is 2.505 × 106 Da. Fourier transform infrared spectrometry (FT-IR) and nuclear magnetic resonance (NMR) results showed that the EPS was composed of glucose/glucopyranose subunits linked by an α-(1 → 6) glycosidic bond and contained an α-(1 → 3) branching structure. X-ray diffraction (XRD) analysis revealed the amorphous nature of the EPS. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that the isolated EPS had a smooth and compact surface with several protrusions of varying lengths and irregularly shaped material. Moreover, the studied EPS showed good thermal stability, water holding capacity, and milk coagulation ability and promoted the growth of probiotics. L. plantarum EPS may be used as prebiotics in the fields of food and medicine
An anoikis-related gene signature for prediction of the prognosis in prostate cancer
PurposeThis study presents a novel approach to predict postoperative biochemical recurrence (BCR) in prostate cancer (PCa) patients which involves constructing a signature based on anoikis-related genes (ARGs).MethodsIn this study, we utilised data from TCGA-PARD and GEO databases to identify specific ARGs in prostate cancer. We established a signature of these ARGs using Cox regression analysis and evaluated their clinical predictive efficacy and immune-related status through various methods such as Kaplan-Meier survival analysis, subject work characteristics analysis, and CIBERSORT method. Our findings suggest that these ARGs may have potential as biomarkers for prostate cancer prognosis and treatment. To investigate the biological pathways of genes associated with anoikis, we utilised GSVA, GO, and KEGG. The expression of ARGs was confirmed by the HPA database. Furthermore, we conducted PPI analysis to identify the core network of ARGs in PCa.ResultsBased on analysis of the TCGA database, a set of eight ARGs were identified as prognostic signature genes for prostate cancer. The reliability and validity of this signature were well verified in both the TCGA and GEO codifications. Using this signature, patients were classified into two groups based on their risk for developing BCR. There was a significant difference in BCR-free time between the high and low risk groups (P < 0.05).This signature serves as a dependable and unbiased prognostic factor for predicting biochemical recurrence (BCR) in prostate cancer (PCa) patients. It outperforms clinicopathological characteristics in terms of accuracy and reliability. PLK1 may play a potential regulatory role as a core gene in the development of prostate cancer.ConclusionThis signature suggests the potential role of ARGs in the development and progression of PCa and can effectively predict the risk of BCR in PCa patients after surgery. It also provides a basis for further research into the mechanism of ARGs in PCa and for the clinical management of patients with PCa
Identification of the surface-associate proteins and functions of enolase of streptococcus mutans
This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department ([email protected])
Streptococcus mutans Surface α-Enolase Binds Salivary Mucin MG2 and Human Plasminogen
Matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis identified enolase as a cell surface component of Streptococcus mutans, which was confirmed by enzyme-linked immunosorbent assay, Western blotting, and transmission electron microscopy. Surface enolase was demonstrated to bind to human plasminogen and salivary mucin MG2. The results suggested a role for enolase in S. mutans attachment, clearance, or breach of the bloodstream barrier
Glucansucrase Produced by Lactic Acid Bacteria: Structure, Properties, and Applications
Glucansucrase (GS) belongs to the GH70 family, which not only can synthesize exopolysaccharides (EPSs) with different physicochemical properties through glucosyl transglycosylation (by hydrolyzing sucrose) but can also produce oligosaccharides. Different strains produce different GSs, which catalyze the synthesis of EPS with different glycosidic bond structures; these EPSs have different biological functions. As an important enzymatic tool, GS has great potential in health care medicine, biological materials, ecological protection, the food chemical industry, etc. GS is mainly produced by lactic acid bacteria (LAB), including Leuconostoc, Streptococcus, Lactobacillus, and Weissella species. With the elucidation of the crystal structure of GS and the advancement of genome sequencing technology, its synthesis reaction mechanism and specific structural characteristics are gradually becoming clear. This review summarizes the isolation, purification, physical and chemical properties, detection methods, sources, and applications of GS in order to provide a reference for the research and development of GS
Research on sectional constant slip control of linear induction motor based on parameter self-tuning
Linear induction motor (LIM) has the advantages of low noise, strong climbing ability and small turning radius. It is widely used in middle-low speed maglev traffic. However, in actual operation, the linear motor will weaken the thrust output due to the existence of the end effect which will lead to the reduction of the traction efficiency. At the same time, the fluctuation of normal force will disturb the suspension system and affect its suspension stability. To solve the above problems, this paper first establishes a LIM dynamic model considering the end effect, and proposes constant slip frequency vector control. According to the different requirements of normal force and thrust of the train in constant power and force area, the sectional constant slip control is carried out. Then an improved particle swarm optimization (IPSO) is introduced to optimize slip frequency at two stages to reduce the theoretically solved error of optimal slip frequency. Finally, the proposed algorithm is simulated and hardware-in-the-loop tests are carried out; The experimental results show that the proposed algorithm and improvements can meet the requirements of full speed thrust output and normal force of the train. It provides a certain reference value for traction control of the linear motor in middle-low speed maglev train
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