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The performance of angular acceleration gain coefficient of driving wheels is investigated in this paper. To identify the interrelations between vehicle and road, the changes of parameters in wheel slip process were analyzed and the concept of angular acceleration gain coefficient was put forward. The relation of gain coefficient with slip ratio and the relation of adhesion coefficient with slip ratio were analytically obtained. The real vehicle driven on the road was tested to verify the above study. The tested results show that the changing trend of angular acceleration gain coefficient and adhesion coefficient in slip process of driving wheels is consistent. Each coefficient has peak point, which corresponds with the optimized slip ratio. [ABSTRACT FROM AUTHOR]

Various types of milk powder purportedly providing diverse health functions have emerged with the growth of the country's elderly population. Some manufacturers illegally add chemical drugs to their products to achieve their reported benefits, which poses a threat to consumer health. The existing standard methods are inapplicable to such complex sample matrices and require testing based on functional claims and classification. These limitations not only consume manpower and resources but also seriously impede daily regulatory efforts to detect unknown risk substances. In this study, a high-throughput method for the screening and quantitative analysis of 300 illegally added chemical drugs in functional milk powder and an identification strategy for unknown structural analogues were established using Zeno SWATH ® data-independent acquisition (DIA) ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) technology combined with a QuEChERS sample purification method. The QuEChERS purification process was developed according to the characteristics of milk powder matrix. The supernatant was separated on a Kinetex F5 column (100 mm×3.0 mm, 2.6 μm) by gradient elution using 5 mmol/L ammonium formate aqueous solution (0.1% (v/v) formic acid, ) and methanol-acetonitrile (1∶1, v/v) as mobile phases. The method was validated in terms of selectivity, linearity, limits of detection and quantification (LODs and LOQs, respectively), matrix effect, accuracy, and precision. Based on a screening database for the 300 target substances, electron-activated dissociation (EAD) fragmentation was applied to obtain rich secondary MS fragmentation information, and unknown structural analogues were identified and confirmed through fragment attribution analysis. The results indicated that all compounds had good linear relationships in certain ranges with correlation coefficients >0.99. The LODs and LOQs were 0.04-2.7 and 0.2-8.0 μg/kg, respectively. The average recoveries at three spiked levels were in the range of 73.1%-125.2%, and the relative standard deviations were ≤14.8% ( n =6). When the developed method was applied to detect illegally added chemicals in 60 functional milk powder samples, it detected benzoguanidine and sildenafil and successfully identified ethylphenidate, which is the structural analogue of an amphetamine. The proposed method is simple, sensitive, and accurate; thus, it may have practical application value for the daily supervision and law enforcement of milk powders with reported health functions.

Objective: To investigate the effect of different arterial occlusion pressure and intermittent time on KAATSU-loaded deep-squat exercise on the characteristics of thigh muscle activation, find out the suitable relative value of personal blood pressure limit causing the maximum activation, and to provide some theoretical basis and practical reference for athletes to carry on the KAATSU Training scientifically. Methods: Ten elite male players were recruited, four kinds of external pressure condition with 0% arterial occlusion pressure (AOP), 40%AOP, 50%AOP, 60%AOP, respectively, were performed with 30%1RM(One repetition maximum)intensity of intermittent and continuous KAASTU-loaded deep-squat exercise. Wave plus wireless surface electromyography instrument was used to collect the surface EMG signals of the lower thigh muscle group. Root mean square (RMS) calculation was used to estimate muscle activity level. The normalized RMS values of the anterior thigh group and posterior thigh group were calculated by RMS of MVC, two-factor ANOVA analysis of variance were used to explore the effect of the activation of various muscle on external express and intermittent mode, to analyze the discrepancy during different external pressure. Results: ①A two-factor analysis of variance showed that different %AOP had significant effect on the normalized values of RMS of muscle measured by KAATSU deep-squat exercise( P ＜0.05), but intermittent mode had no significant effect on the standard value of RMS of muscle( P ＞0.05). The interaction of external pressure and intermittent mode on muscle RMS was not significant( P ＞0.05); ②The normalized RMS values of Rectus Femoris, Vastus Medialis, Vastus Lateralis, Biceps Femoris, Semitendinosus were significantly increased ( P ＜0.05)in 50% AOP pressure condition during intermittent and continuous exercise; ③ The normalized RMS values of RF and VL were significantly increased( P ＜0.05)in 50% AOP pressure condition during intermittent and continuous exercise. The %MVC values of Vastus Medialis and Semitendinosus were significantly increased( P ＜0.05)in 60% AOP pressure condition during intermittent exercise. Conclusion: This study further verified that 50% AOP pressure can significantly improve the optimal activation quadriceps and posterior thigh groups and produce the best training effect for the high level handball players. It can not only promote the coordinated development of the agonist and antagonist, but also avoid overloading and prevent hamstring injury. At the same time, the intermittent mode is recommended to adopt the decompression intermittent mode.

To establish the method for determining non-volatile ingredients of neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, isochlorogenic acid A, rosmarinic acid, ferulic acid, rutin, luteoloside, isoquercitrin, hesperidin, diosmin, diosmetin, luteolin, acacetin and linarin in Menthae Haplocalycis Herba formula granules and traditional herbal pieces by UPLC-MS/MS, and analyze the correlation of non-volatile ingredients in Menthae Haplocalycis Herba formula granules and traditional herbal pieces. Shim-pack GIST C_(18) column(2.1 mm×100 mm, 2 μm) was adopted with acetonitrile-0.1% formic acid aqueous solution as the mobile phase for gradient elution at the flow rate of 0.4 mL·min~(-1). The column temperature was set at 35 ℃. The quantitative analysis was performed using the electrospray ionization source and the multiple reaction monitoring. The linear relationship, resolution, repeatability and recovery of the 16 chemical components all met the requirements. The 16 non-volatile ingredients in traditional herbal pieces of Menthae Haplocalycis Herba could be tracked in formula granules. There were certain differences of the 16 chemical components among Menthae Haplocalycis Herba formula granules of different manufacturers and traditional herbal pieces of different producing areas. The UPLC-MS/MS method was simple, rapid and accurate, and could be used for the quality control of non-volatile ingredients in Menthae Haplocalycis Herba formula granules and traditional herbal pieces.

Objective: To investigate the reversing effect of icaritin on multidrug resistance of multiple myeloma cell lines KM3/BTZ and its underlying mechanism., Methods: KM3/BTZ cells were established by a gradually ascending gradient induction of bortezomib (BTZ). The sensitivities of KM3 and KM3/BTZ cells to 7 chemotherapeutic drugs, the inhibition and reversal effects of icaritin on proliferation and drug-resistance of KM3/BTZ cells were analyzed by MTT. The apoptosis was analyzed by flow cytometry, and the expression of Par-4, HSP27 and P-gp were detected by Western blot., Results: KM3/BTZ cells were not only resistant to BTZ, but also to other 6 chemotherapeutic drugs. The resistance index (RI) to BTZ was 17.84, and higher than that of other chemotherapeutic drugs. Icaritin inhibited the proliferation and induced the apoptosis of KM3/BTZ cells. The IC 50 value of BTZ decreased from 0.345 µg/ml to 0.149 µg/ml, and the reversal index was 2.38 (P<0.05). The expression of Par-4 protein increased in a concentration-dependent manner, while the expression of HSP27 and P-gp were down-regulated., Conclusion: Icaritin can inhibit cell proliferation and induce apoptosis of KM3/BTZ cells, moreover, can effectively reverse the multidrug resistance of KM3/BTZ cells. The mechanism may be related with down-regulation of HSP27 and P-gp expression, and up-regulation of Par-4 expression.

This study was designed to use iTRAQ technology coupled with 2D LC-MS/MS to study the comparative proteomics of different processing technology for pilose antler. 1015 proteins were identified with 2D LC combined with MOLDI TOF/TOF mass spectrometry. Comparative analysis with Protein Pilot (Version 4.5) revealed that 87 proteins were changed (P ≤ 0.05, the ratio of > 1.50 or < 0.60 as the threshold selection of difference proteins), of which 24 were up regulated and 33 were down regulated in the traditional frying process (TFP) compared with the fresh pilose antler (P ≤ 0.05). 7 significant different proteins (P ≤ 0.001), most of these significantly changed proteins were found to be involved in calcium ion binding and ATP binding associated with human healthy. Freeze drying with protective agent (FDP) (Trehalose) can improve the content of significantly different proteins (P ≤ 0.001) including Collagen alpha-1 (XII) chain (COL12A1) and Collagen alpha-1 (II) chain (COL2A1). The significant function involves in platelets activating, maintenance of spermatogonium, and disorder expression in tumor cells. The functional annotation by Hierarchical clustering and GO (gene ontology) showed that the main molecule functions of the proteins significantly changed in these processes were involved in binding (52.7%), catalytic (25.3%), structural molecule and transporter (6.6%).

Research on and development of the high amplitude, broadband terahertz system based on ultra-short pulse, low-power laser system is a hot spot in the field of terahertz. So far, for all the reported THz bandwidths broader than 10 THz, there always exist strong dispersion and absorption gaps associated with the lattice resonance in either the photoconductive materials or crystalline EO materials. If such THz sources and detectors are employed in spectroscopic studies, spectral information in these gaps cannot be extracted. One of the advantages of using amorphous electro-optic polymer films as THz emitters and sensors is that there is no dispersion or absorption resulting from the lattice resonance effect, making a gap-free THz spectrum possible. Another advantage of electro-optic polymer films is the ease of fabrication and handling, in contrast to the extremely thin crystalline electro-optic materials used for existing broadband THz system. In addition, we can engineer the electro-optic polymeric materials to achieve small phase mismatch and high electro-optic coefficients such that brightness and broad bandwidth of THz radiation can be obtained. In this thesis a theoretical description of electro-optic effect based on electro-optic polymer and the second- order nonlinear chromophores synthesis is reviewed. In the past 20 years, progress in electro-optic polymer in the field of generating and detecting terahertz radiation by all-optical techniques is summarized, including the terahertzs systems based on copolymer and the guest-host polymer induced by Titanium doped sapphire femtosecond laser and based on the guest-host polymer at communication wavelengths.

Objective: To discuss the origin of occupational stress among petrochemical industry workers and to access the main occupational stressors that impact job satisfaction and mental health of petrochemical industry workers., Methods: A survey on occupational stressor was carried out by Occupational Stress Indicator (OSI) in 532 petrochemical industry workers (345 chemical and 187 logistic workers)., Results: The environment in workplace of chemical group was worse than that of contrast. The chemical workers had less control over job and they experienced more hazards, monotonous as well as role stressors than the logistic group. The scores of job satisfaction and mental health of chemical group (36.867 +/- 0.656, 43.734 +/- 0.542, respectively) were higher than that of contrast (40.321 +/- 0.901, 46.714 +/- 0.745, respectively) (P < 0.05)., Conclusion: The occupational stressors exist in chemical workers which affect chemical workers' job satisfaction and mental health with different levels.

Mutations in mitochondrial DNA have been associated with a wide spectrum of clinical abnormalities. We reported here the clinical and genetic evaluations as well as mutational analysis of mitochondrial DNA(mtDNA) in a three-generation Chinese Han family with maternally transmitted hearing loss and epilepsy. Of 14 matrilineal relatives, three suffered from hearing loss, three had epilepsy, and other did not have significant clinical abnormalities. Sequence analysis of mitochondrial genome in this family identified the novel 7472delC in tRNASer(UCN) and 33 variants belonging to Asian haplogroup B4b1a2. The 7472delC locates at the highly conserved residue of T-arm of this tRNA. In fact, the 7472insC at the same position of this tRNA has been associated with hearing loss and epilepsy in several genetically unrelated families. The 7472insC has been shown to lead to a failure in tRNA metabolism and mitochondrial dysfunction. Thus, 7472delC mutation, similar to 7472insC mutation, may result in the mitochondrial dysfunctions responsible for the hearing loss and epilepsy. Furthermore, none of mutation in deafness-associated GJB2 gene was detected in this Chinese family. Therefore, the 7472delC is likely a new mitochondrial mutation with hearing loss and epilepsy.

We report here the clinical and genetic evaluations as well as mutational analysis of mitochondrial DNA (mtDNA) in a four-generation Chinese Han family with aminoglycoside-induced and nonsyndromic hearing loss. Strikingly, this family exhibited a high penetrance and expressivity of hearing loss. The penetrances of hearing loss in this family were 75% and 41.7% respectively, when aminoglycoside-induced deafness was included or was excluded. The severity of hearing loss in matrilineal relatives varied from profound hearing loss to normal hearing. Mutational analysis of mtDNA identified the homoplasmic A1555G mutation and a distinct set of mtDNA variants belonging to the Asian haplogroup B5b. Of these, the G15927A mutation absent in 156 Chinese controls is localized at the anticodon-stem of tRNAThr at conventional position 42. The guanine at this position (G42) of tRNAThr is highly conserved from bacteria to human mitochondria. Thus, it is antici-pated that the G15927A disrupted the highly conserved C-G base-pairing at the anticodon-stem of tRNAThr. The alteration of structure of this tRNA likely leads to a failure in tRNA metabolism, thereby worsens the mitochondrial dysfunction asso-ciated with the A1555G mutation. Thus, the G15927A mutation has a potential modifying role in increasing the penetrance and expressivity of hearing loss associated with the deafness-associated 12S rRNA A1555G mutation in this Chinese pedigree.

Objective: To explore the adverse effects of coking oven emissions (COE) on the serum oxidation-reduction and relevant genes in the exposed workers., Methods: Fifty-six coke oven workers and forty controls were investigated. Serum Malondialdehyde (MDA) levels and the activities of total superoxide dismutases (T-SOD) were measured by spectrophotometrical method. Immunohistochemical method was used to assess the P21 and P53 levels in peripheral white blood cells., Results: Compared with controls, the individuals exposed to COE had significantly increased levels of serum MDA [(5.30 +/- 2.29) nmol/mL, P < 0.01] and markedly decreased levels of T-SOD [(100.04 +/- 10.75) NU/mL]. Additionally, the median levels of P53 and P21 were markedly increased in the exposed individuals compared with the controls (21.4% and 23.2%, respectively, all P < 0.05)., Conclusion: The findings indicate that occupational exposure to COE causes the rise of serum oxidation-reduction MDA and the fall of T-SOD, and increasing expression levels of P21 and P53 proteins before the occurrence of apparent clinical symptoms.

Objective: To observe the change of surface active agents of eustachian tube of guinea pigs suffering from secretory otitis media, to explore the effects of surface active agents on secretory otitis media., Methods: To establish the animal model of guinea pigs suffering from secretory otitis media. To analyse the changes of biochemical component and activity of eustachian tube's surfactant, meanwhile; to observe surfactant change after ectogenic surfactant treatment., Results: The main components of the surfactant decrease in the model group of guinea pigs suffering from secretory otitismedia, phosphatidylcholine (PC) is (19.9 +/- 1.7)%, phosphatidylethanolamine(PE) is (36.8 +/- 2.7)%, minimum surface tension (gamma min) is (18.5 +/- 2.4) mN/m, and PC is (25.7 +/- 2.1)%, PE is (43.7 +/- 3.8)%, (P < 0.001), and gamma min is (7.6 +/- 0.8) mN/m in normal group (P < 0.001). After giving Ectogenic surfactant treatment, PC and PE increase, PC is (23.3 +/- 2.2)%, PE is (42.5 +/- 3.6)%; gamma min reduce, it is (11.8 +/- 2.3) mN/m., Conclusions: The main biochemical components of the surfactant obviously decrease, the activity of the surfactant weakens in secretory otitis media of guinea pig. This study showed the treatment of Ectogenic surfactant is effective.