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The growth inhibitions of four commercially available isomerized hop products, in which dihydro iso-α-acids, tetrahydro iso-α-acids, and hexahydro iso-α-acids are derived from natural iso-alpha-acids, against brewing-related microorganisms were studied. The tests were carried out in three media: liquid (broth, pH 6–7), solid (agar, pH 6–7) and beer (pH 4.2). The results indicate that Staphylococcus aureus (S. aureus) ZJ007 (G+) was the most sensitive strain to any hop product at the lowest concentration of 0.1 g/L in liquid and 0.5 g/L in solid. However, in liquid media, hexahydro iso-alpha-acids showed significant antibacterial potency on E. coli DH5a and Lactococcus species AB133 at 0.5 g/L (equating to 50 mg/L concentration). Interestingly, the growths of E. coli DH5α (G−) and wild Saccharomyces cerevisiae BY101 (wild yeast), respectively, in the solid media were inhibited by hexahydro and tetrahydro iso-alpha-acids (equating to 250–500 mg/L) and dihydro and iso-alpha-acids (750–1500 mg/L), and no effect on Saccharomyces cerevisiae (DM303). By the same means, the growths of Lactococcus species AB133 (possible hop resistant, G+) and Lactococcus lactis NZ9000 (hop-resistant G+, tolerated to iso-alpha-acids) were inhibited by hexahydro > tetrahydro iso-alpha-acids (equating to 500 mg/L) and not affected by dihydro and iso-alpha-acids. Overall, the hexahydro iso-alpha-acids are the most effective bacteriostat. The microscopy did not detect any strain in the inoculated and hopped beer (≥ 50 mg/L or BU) precipitates after fermentation. The GC–MS analysis showed insignificant aroma difference compared to the control beer (DM303 yeast only). For the implications, four isomerized hop products are more soluble and offer higher concentration in any neutral medium (pH 6–7) than their undissociated forms (pH ≤ 4). In the milder pH range, their antibacterial behavior is hexahydro > dihydro > tetrahydro ~ iso-alpha-acids.

Aluminum coating was prepared on composite material surface by using oxygen-acetylene flame spraying technology. The H01-103H sealants were used to seal the thermal sprayed aluminum coatings. The characteristics of the aluminum coatings with and without H01-103H sealant, including surface morphologies, phase composition, and bonding strength, were investigated by means of SEM, EDS, and mechanical testing machine. Thermal shock experiment and low temperature cooling test were also used to examine the thermal shock resistance and frost resistance of the Al coatings. Electrical conductivity and electromagnetic shielding properties were then tested according to four-probe measurement principle and GJB 5239-2004, respectively. The results showed that the bond strength was 7.36 MPa and the surface porosity was about 5.21% for Al coating without H01-103H sealant, in addition, the H01-103H sealants could fill into the pores, reducing the porosity and increasing the bond strength of the coating. Furthermore, the main component of the coating was Al, the oxygen content was only 1.43%. Flame sprayed aluminum coating, with surface electrical resistance 0.89 mΩ and 5–18 GHz electromagnetic shielding effectiveness above 35 dB, was an ideal candidate for electromagnetic shielding utilization. The Al coating remained intact, compact, no cracks, peeling, layering under 50–200°C and −30°C, which showed good thermal shock resistance and frost resistance.

In this experiment, two hops varieties Simcoe and Saaz were selected as the research objects to explore the influence of hops on beer flavor after aging treatment under different conditions. The hops obtained under five different aging conditions were subjected to fermentation experiments. The aroma characteristics of hop oil, beer samples at different brewing stages and finished beer were analyzed by gas chromatography-mass spectrometry (GC/MS). The results showed that, except caryophyllene oxide (0.21 μ g/L and 0.15 μg/L), the contents of other aroma compounds decreased. The results of expert sensory evaluation and consumer evaluation survey were combined with the experimental data for analysis. We found that moderate aging may make beer more drinkable. Among them, hops represented by Simcoe with more aroma substances will lose their original aroma after aging. However, hops with higher humulus content represented by Saaz became softer after moderate aging treatment.

PurposeThe treatment of osteosarcoma of the spine remains controversial. Our aim is to explore the treatment of patients with spinal osteosarcoma. MethodsWe analyzed the date collected 727 spinal osteosarcoma patients from the Surveillance Epidemiology and End Results (SEER) databases between 1973 and 2015. X-tile software was performed to find the optimal cut-off values of age and economic income. Univariate and Multivariate Cox analyses were used to identify the independent prognostic factors. Logistic regression model was conducted to clear the factors associated to surgical compliance; Kaplan-Meier estimator method was adopted to analyze the Overall survival (OS) and Cancer-specific survival (CSS). ResultsAmong 727 eligible spinal osteosarcoma patients, 370 (50.9%) patients received surgical treatment, 357 (49.1%) cases without surgery. There were significant differences in the effects of age at diagnosis, SEER historic stage and tumor grade on surgical treatment (All P < 0.05). Surgery was an independent prognostic factor for OS and CSS of spinal osteosarcoma patients. Spinal osteosarcoma patients undergone surgery group showed favorable survival than the other group.ConclusionsSurgery can provide survival benefits for patients with osteosarcoma of the spine. Spinal osteosarcoma patients with undergone surgery have favorable survival and surgery can become a suitable treatment for patients.

With the application of “ λ” type composite skin becoming more and more extensive and diversified, its precise forming technology is also widely concerned. This article mainly solves the quality problems of “ λ” type corner area, such as delamination dispersion and surface wrinkle, which exist in reality commonly in the manufacturing process. The prepreg is heated along the corner area of the tooling to solve the problem that prepreg is difficult to be compacted due to the large modulus of carbon fiber in “ λ” type corner area. Furthermore, two precompaction tests are creatively increased at 16 layers (middle layer) and 32 layers (last layer) for the thick structure, respectively, to ensure the compaction effect of the blank. In addition, combined with the characteristics of highly elastic rubber and carbon fiber-reinforced materials, a new type of soft mold structure with proper flexibility and good stiffness is proposed innovatively through the reasonable placement of carbon fiber-reinforced materials and the setting of exhaust holes according to the structure characteristics of “ λ” type root skin. Through further process verification, it is shown that the improved process has effectively solved the problems of wrinkles and internal delamination at the sharp corners of parts and realized zero-defect manufacturing of “ λ” type root skin for the first time.

Kernel principal component analysis (KPCA) has been widely used in chemical processes monitoring due to its simple principle. However, how to select the kind and parameters of kernel function still limits the application of the method until now. In this paper, an optimization method based on genetic algorithm is developed to choose proper kind and parameters of kernel function. In this method, kernel kind and parameters are seen as decision variables of optimization, using correct monitoring rate, number of principal components, and statistical control limit of square prediction error (SPE) as multi-objective. For this specific problem, the fitness function, the algorithm of genetic selection, crossover and mutation are designed to ensure the diversity of kernel function and more selected chances of optimal individual in evolution process. A simple example and penicillin fermentation process are used to investigate the potential application of the proposed method; simulation results show that the proposed method is effective.