BackgroundPhytic acid and phytates can interact with biomolecules, such as proteins and carbohydrates, and are anti-nutritional factors found in food and feed. Therefore, it is necessary to remove these compounds in food and feed processing. Phytase can hydrolyze phytic acid and phytates to release a series of lower phosphate esters of myoinositol and orthophosphate. Thus, the purification and characterization of novel phytases that can be used in food and feed processing is of particular interest to the food and feed industries.ResultsA novel neutral and heat-tolerant phytase from a newly isolated strain Bacillus nealsonii ZJ0702 was purified to homogeneity with a yield of 5.7% and a purification fold of 44. The molecular weight of the purified phytase obtained by SDS-PAGE was 43 kDa. The homology analysis based on N-terminal amino acid and DNA sequencing indicated that the purified phytase was different from other known phytases. The optimal thermal and pH activity of the phytase was observed at 55°C and 7.5, respectively. Seventy-three percent of the original activity of the phytase was maintained following incubation at 90°C for 10 min. The phytase was stable within a pH range of 6.0 − 8.0 and showed high substrate specificity for sodium phytate. Cu2+, Co2+, Zn2+, Mn2+, Ba2+ and Ni2+ ions were found to inhibit the activity of the phytase.ConclusionsA novel phytase purified from B. nealsonii ZJ0702 was identified. The phytase was found to be thermally stable over a wide temperature range at neutral pH. These properties suggest that this phytase is a suitable alternative to fungal phytases for the hydrolysis of phytic acid and phytates in food and feed processing industries.

Aim: We aimed to identify metabolic characteristics of early-stage heart failure (HF) and related biomarkers. Patients & methods: One hundred and forty-three patients with New York Heart Association class I–IV HF and 34 healthy controls were recruited. Serum metabolic characteristics of class I HF were analyzed and compared with those of class II–IV HF. Potential biomarkers of class I HF with normal N-terminal-pro-B-type natriuretic peptide (NT-proBNP) level were screened and validated in additional 72 subjects (46 class I patients and 26 controls). Results & conclusion: Eleven metabolites were found disturbed in class I HF, and five of which were also disturbed in class II–IV HF. Glutamine and tyrosine showed high value to identify class I HF with normal NT-proBNP level. The diagnostic potential of glutamine was partially confirmed in the validate set, holding a promise to detect early HF with normal NT-proBNP level.

The 403-seat Kung Hsue She (KHS) Concert Hall features a small proscenium stage designed to accommodate a wide range of performances. Attention to room acoustical design emphasized broadening the variability, while recitals by pianists and singers were considered primary. These competing purposes were realized by integrating stage curtains with the stage shell and the coupled volume outside the shell. Detached lateral reflectors were introduced to minimize sound level drop due to use of moveable curtains around the audience. The proposed design strategies were tested using a scale model and were verified in the completed hall.

In recent years, under the background of stable economic operation, people's research on economic systems has become increasingly popular. The dynamic input-output model reflects the change and development process of the input-output relationship of the economic system over a period of time. The main purpose of tracking control is to design a suitable controller so that the output of the control system can track the output of the reference system as much as possible. In the economic system, data is an important factor. Based on this, this paper mainly studies the tracking control of dynamic input-output economic system based on data fusion. This research takes the data fusion of the dynamic input-output economic system as the starting point and takes the optimal control and tracking of the economic system as the research object of this research. Based on data fusion technology, a new dynamic input-output economic system tracking and control is proposed. This paper studies the finite-time optimal tracking control of linear systems. Through numerical examples, comparing the finite-time and infinite-time optimal control simulation results, it is proved that the algorithm can achieve good tracking control. Experimental data shows that the optimal and suboptimal performance indicators for a limited time are 0.7729412 and 1.5687310, respectively. Therefore, compared with the infinite-time optimal control, the performance loss and the final tracking error of the suboptimal control proposed in this study are reduced.

The impact of source directivity can be significant for chamber music performances, in particular for arena-type halls that have visual intimacy. This study has been carried out to understand the physical and perceptual aspects of the seats surrounding the platform in recital halls. Effects of architectural features were evaluated using computer simulations that accounted for source directivity and diffusive reflections. Both live and recorded subjective evaluations of chamber music performances were made in an actual hall while acoustical measurements were also taken. As a result, computer simulations using a singer source showed significant decrease in both clarity and strength in the 2-kHz band for the seats surrounding a centered platform. A wall 6 m in front of the platform was effective in mitigating the problems. Sound levels calculated from the recordings taken from various viewing angles were correlated with subjective evaluations, especially in the high frequencies. Timbre appeared to be the principal factor influencing solo performances and balance was the most important in judging ensembles. Nevertheless, live evaluation showed no significant difference among the listening positions.