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Objective: The objective of this study was to develop high-quality non-fried whole shiitake (Lentinus edodes) crisps due to having high oil content of vacuum fried L. edodes crisps which inevitably pose health risks after long-term use. Methods: Based on uniform design, instant controlled pressure drop (DIC) was used to investigate the influences of moisture content after heat pump pre-drying, puffing temperature and vacuum drying temperature on the puffing degree, rehydration ratio, total color difference, hardness and crispness of L. edodes crisps. The polynomial regression model was established by using a weighted comprehensive score method, and it was optimized and verified accordingly. Results: The optimum parameter combinations of L. crisps during DIC processing were moisture content after heat pump pre-drying of 35.63%, puffing temperature of 100 ℃, vacuum drying temperature of 64.17 ℃. Under the control of these optimal parameter combinations, the puffing degree of L. crisps was 69.34%, total color difference was 20.68, hardness was 108.16 N, and crispness was 75.79. Conclusion: Uniform design combined with response surface methodology can be used to optimize processing parameters of DIC crisps and obtain high quality non-fried L. crisps.

Objective To summarize the clinical manifestations and histopathological characteristics of skeletal muscle in scleromyositis patients with positive anti‑Ku or anti‑PM‑Scl antibodies. Methods and Results Retrospective collection of clinical data from 70 scleromyositis patients diagnosed at Peking University First Hospital from January 2010 to March 2023, analysis showed the average onset age of patients was 36.00 (20.75, 51.25) years old. The initial symptoms of 77.14% (54/70) patients was mainly in the proximal limbs myasthenia [74.29% (52/70)], mild to moderate [77.14% (54/70)], and 52.86% (37/70) patients had systemic symptoms such as fatigue or skin involvement during the course of the disease. The serum creatine kinase (CK) level was 2775.00 (995.50, 4995.75) U/L. About 32.86% (23/70) were positive for anti‑Ku antibody, 65.71% (46/70) were positive for anti‑PM‑Scl antibody, 1.43% (1/70) were both positive, and 27.14% (19/70) could also had increased level of other myositis antibodies. The main histopathological changes were inflammatory [41.43% (29/70)] or necrotic [24.29% (17/70)] myopathic pathological changes, presenting as muscle fiber atrophy [91.43% (64/70)], necrosis [68.57% (48/70)] or regeneration [85.71% (60/70)]. Comparison of symptoms, signs and histopathological characteristics of skeletal muscle between patients with positive anti‑Ku antibody and with positive anti‑PM ‑Scl antibody, female proportion (χ2 = 4.381, P = 0.036) and C5b9 deposition damage (χ2 = 4.725, P = 0.030) were higher in the former than those in the latter. Conclusions Scleromyositis patients with positive anti‑Ku or anti‑PM‑Scl antibodies mostly started in young and middle age, mainly manifesting as mild to moderate myasthenia in the proximal limbs, and skeletal muscle inflammatory or necrotic myopathic lesions as characteristic pathological changes. Compared with positive anti ‑ PM ‑ Scl antibody patients, positive anti ‑ Ku antibody scleromyositis patients were mainly female, and skeletal muscle complement deposition was more notable.

Objective To evaluate the diagnostic value of skeletal muscle biopsy in asymptomatic and pauci‑symptomatic hyperCKemia. Methods and Results A total of 146 patients with asymptomatic or pauci ‑ symptomatic hyperCKemia diagnosed in Peking University First Hospital from July 2020 to February 2023 were selected, and skeletal muscle biopsy was performed. About 72.60% (106/146) had histological changes, including muscular dystrophy (n = 73), inflammatory or necrotizing myopathy (n = 16), other myopathy (n = 15), and neurogenic skeletal muscle damage (n = 2). The positive rate of pathological diagnosis was 50.68% (74/146), including muscular dystrophy 82.43% (61/74), inflammatory myopathy 8.11% (6/74) and metabolic myopathy 9.46% (7/74). The positive rate of etiological diagnosis was 85.62% (125/146), including muscular dystrophy 67.20% (84/125), inflammatory myopathy 13.60% (17/125), metabolic myopathy 7.20% (9/125) and other causes 12% (15/125). Compared with different subgroups, the proportion of pathological changes (χ2 = 14.043, P = 0.000; χ2 = 12.740, P = 0.000), the positive rate of pathological diagnosis (χ2 = 10.641, P = 0.001; χ2 = 25.530, P = 0.000) and etiological diagnosis (Fisher's exact probability: P = 0.001; χ2 = 10.811, P = 0.001) in the significantly elevated creatine kinase (CK) level group and the adolescent group was significantly higher than those in the mildly elevated CK level group and the adult group. The positive rate of pathological diagnosis in the asymptomatic group was higher than the pauci‑symptomatic group (χ2 = 4.792, P = 0.029). There were significant differences in the etiological ratio between the mildly elevated CK level group and the significantly elevated CK level group (Fisher's exact probability: P = 0.000), the adolescent group and the adult group (χ2 = 86.149, P = 0.000), and the asymptomatic group and the pauci ‑ symptomatic group (χ2 = 20.608, P = 0.000). Conclusions Skeletal muscle biopsy was important in etiological diagnosis of asymptomatic and pauci‑symptomatic hyperCKemia. Muscular dystrophy is a common cause of asymptomatic and pauci‑symptomatic hyperCKemia.

The quality safety risks and quality management issues of traditional fermented meat products were analyzed. This paper put forward suggestions on increasing research and development efforts, accelerating the knowledge benefit transformation process, standardizing the standard system, refining supervision standards, standardizing workshop production, optimizing product markets, strengthening the awareness of social participation, and promoting social co-governance, in order to improve the overall quality and safety level of the traditional fermented meat products industry.

Characterization of dynamic conformational changes in membrane protein complexes by NMR spectroscopy remains challenging. Here authors report the site-specific incorporation of 4-trimethylsilyl phenylalanine (TMSiPhe) into proteins, which enabled the characterization of multiple conformational states of a phospho-β2 adrenergic receptor/β-arrestin-1 complex in response to different receptor ligands.

BACKGROUND Assessment of homogeneity of Environmental Reference Material (ERM) is one of the most important steps for the development of an ERM. The data drift has a serious negative effect on the assessment of homogeneity and uncertainty of ERM. OBJECTIVES To develop the drift correction methods for homogeneity test of ERM. METHODS The drift correction methods were discussed from the aspects of experimental scheme and statistical methods through practical cases. The drift correction methods, such as random analysis, randomized block design, interpolation correction, and trend analysis correction, were introduced in details. RESULTS The t-test method was proposed to judge the significance of data drift. For insignificant drift trend, the random analysis method was useful for the evaluation of uncertainty of homogeneity. If the drift trend was significant, better-corrected results were obtained by using interpolation correction and trend analysis correction methods. For example, after data correction by interpolation correction and trend analysis, the relative standard deviation (RSD) of homogeneity data of Ni in soil decreased from 3.0% to 1.1% and 0.84%, respectively. The absolute value of slope of line decreased from 0.2003mg/kg to 0.02870mg/kg and 4.709×10-5mg/kg. The uncertainties of between-bottle homogeneity of Ni, Cu, Co and Tl decreased by 78% compared with the random analysis method. CONCLUSIONS Data drift correction methods are not effective for long periods of measurement, therefore the experimental scheme of randomized block design method is recommended for homogeneity study.

In this paper, a more computationally convenient singularity condition of the enveloped surface is proposed using the theory of linear algebra. Its preconditions are only the tangential vector of the enveloping surface, the relative velocity vector, and the total differential of the meshing function. It avoids calculating the curvature parameters of the enveloping surface. It is proved that the singularity conditions of enveloped surface from different references are equivalent to each other and the relational equations among them are obtained. The curvature interference theory for the involute worm drive is established using the proposed singularity condition. The equation for the singularity trajectory is obtained. The calculation method for the singularity trajectory is proposed and its numerical result is obtained. The influence of the design parameters on the singularity trajectory is studied using the proposed curvature interference theory. The study results show that the risk of curvature interference is high when the transmission ratio is too small, especially in the case of the single-threaded worm and large modulus. The proposed singularity condition can also be applied to study the curvature interference mechanism in other types of the worm drive and to study the undercutting mechanism when machining the worm drive.

Abstract Background Artificial induction of mutagenesis is effective for genetic resource innovation and breeding. However, the traditional mutation methods for fish breeding are not convenient or safe for daily use. Hence, development of a simple, safe and effective mutagenesis method with a high mutation rate and applicability to multiple fish species, is needed. Results We reported the first successful mutagenesis in a marine aquaculture fish species, Japanese flounder, Paralichthys olivaceus, using a novel atmosphere and room temperature plasma (ARTP) mutagenesis tool. ARTP treatment time was optimized for the fertilized eggs and sperm, respectively. Eggs fertilized for 60 min were treated by ARTP with a radio-frequency power input of 120 W, and the ARTP treatment time was 25 min. Under an ARTP radio-frequency power input of 200 W, the optimal treatment time for sperm diluted with Ringer’s solution by 1:40 v/v was 10 min. The ARTP-treated group presented differences in morphological traits such as body height, total length among individuals at day 90 after hatching. Whole-genome sequencing was used to reveal the mutation features of ARTP-treated individuals collected at day 120 after hatching. In total, 69.25Gb clean data were obtained from three controls and eight randomly selected ARTP-treated individuals, revealing 240,722 to 322,978 SNPs and 82,149 to 86,798 InDels located in 17,394~18,457 and 12,907~13,333 genes, respectively. The average mutation rate reached 0.064% at the genome level. Gene ontology clustering indicated that genes associated with cell components, binding function, catalytic activity, cellular process, metabolic process and biological regulation processes had higher mutation rates. Conclusions ARTP mutagenesis is a useful method for breeding of fish species to accelerate the selection of economically important traits that would benefit the aquaculture industry, given the variety of mutations detected.

Different pretreatment methods should be used for quick and accurate determination of major and minor elements in different types of polymetallic ores. In this study, five types of polymetallic ores including Pb-Zn, Sn, Mo, V, and Cu-Ni polymetallic ores were collected from typical metallogenic areas of China. Comparison of microwave digestion using mixed acids of hydrochloric-nitric-perchloric-hydrofluoric-sulphuric acids with digestion using nitric acid only was performed. Nine elements, Cu, Pb, Zn, Sn, W, Mo, Mn, Ti, and V were determined by the Inductively Coupled Plasma-Optical Emission Spectrometry technique. Analytical results of National Standards Reference indicate that digestion with a mixture of five acids has a long digestion time and can simultaneously determine the 6 elements of Cu, Pb, Zn, Mo, Mn, and V. Digestion with nitric acid needs only 1 h and can determine 4 elements, Cu, Pb, Zn, and Mo. Two methods have good accuracy and precision (RSD < 5%) and low detection limits of 5.3-30 mg/kg, which are suitable for application in geological analyses. However, neither of these two methods are suitable for analyzing Sn, W, and Ti, because these elements cannot be digested completely by acids.

This paper presents an experimental study to evaluate the combined effect of nano-SiO2 particles and steel fibers on flexural properties of concrete composites containing fly ash. In this study, five different nano-SiO2 contents (1%, 3%, 5%, 7%, and 9%) and five different steel fiber contents (0.5%, 1%, 1.5%, 2%, and 2.5%) were used. The results indicate that addition of nano-SiO2 and steel fibers decreases the workability of the concrete composites containing fly ash, and both the slump and slump flow decrease gradually with the increase in nano-SiO2 and steel fiber content. Besides, the addition of nano-SiO2 can greatly increase the flexural strength and flexural modulus of elasticity of concrete composites containing fly ash. There is a tendency for the increase in the flexural strength flexural modulus of elasticity with an increase in the nano-SiO2 content when the nano-SiO2 content is below 5%, while both of the two flexural parameters begin to decrease after the nano-SiO2 content above 5%. Furthermore, steel fibers have great improvement on the flexural properties of concrete composites containing fly ash and nano-particles. The flexural strength and flexural modulus of elasticity of concrete composites containing fly ash and nano-SiO2 are more than those of the concrete composite without steel fibers. Both of the two flexural parameters increase with the increase in steel fiber content when the steel fiber content is below 2%, while the flexural parameters begin to decrease after the steel fiber content is above 2%.

The elastic anisotropy and thermodynamic properties of the recently synthesized Pnnm-CN have been investigated using first-principles calculations under high temperature and high pressure. The calculated equilibrium crystal parameters and normalized volume dependence of the resulting pressure agree with available experimental and theoretical results. Within the considered pressure range of 0–90 GPa, the dependences of the bulk modulus, Young’s modulus, and shear modulus on the crystal orientation for Pnnm-CN have been systematically studied. The results show that the Pnnm-CN exhibits a well-pronounced elastic anisotropy. The incompressibility is largest along the c-axis. For tension or compression loading, the Pnnm-CN is stiffest along [001] and the most obedient along [100] direction. On the basis of the quasi-harmonic Debye model, we have explored the Debye temperature, heat capacity, thermal expansion coefficient, and Grüneisen parameters within the pressure range of 0–90 GPa and temperature range of 0–1600K.

In this study, the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design optimization. Four independent variables such as acetone : formaldehyde molar ratio (mol/mol), solution pH value, reaction temperature (℃) and reaction time (min) were considered in the experiments. U*13(134) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 experimentations. The 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression analysis. Minitab (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data analysis. The t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X2X3), the linear terms of acetone : formaldehyde molar ratio (X1), reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1). The optimized results were achieved with the acetone: formaldehyde molar ratio (mol/mol) at 3:1, solution pH value at 6.0, reaction temperature at 70 ℃, and reaction time at 140 min, respectively. This method can not only significantly reduce the number and cost of the tests, but also provide a good experimental design strategy for the development of furan resin. The investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones.