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A complaint against the electronic control diesel engine is that it starts "one second slower" than other conventional mechanical pump diesel engines. That is because that on conventional mechanical pump diesel engines, the phase position between the fuel supply sequence of fuel systems and fuel pump cams is fixed in the starting process and there is no need to cylinder recognition. While on the electronic control diesel engine, the controller cannot determine the specific phase of diesel engine until it receives a sufficient number of crank and cam signals, so as to need cylinder recognition. The establishment process of the control timing sequence at the beginning of the starting (cylinder recognition control) is directly determining the duration of the diesel engine starting process. The cylinder recognition control is one of the most basic parts of the electronic control diesel engine management system. In this work, in order to shorten the process of cylinder recognition, a quick and reliable method to determine the precise phase of diesel engine by possibly reducing the crank and cam speed signal is studied. Firstly, according to the firing order of the target diesel engine, speed signal, and the phase of the electronic control system have been designed, using two sets of speed computing devices of cam and crank, not only can shorten the time of cylinder recognition, but also can help to improve the reliability of the control system. And then two methods are proposed in this work, one is judge mode of counting teeth, the other is judge mode of checking window. By analyzing the working principles of the two modes, judge mode of checking window needs less cam and crank signal to cylinder recognition. In the judge mode of counting teeth, at least two cam signals are necessary for cylinder recognition and in the worst case, the cylinder recognition will not succeed until the engine spins two revolutions. While in the judge mode of checking window, the most rapid cylinder recognition only takes 70° crank angle and in the worst situation, the engine only needs to rotate around a little more than that cylinder recognition can succeed. Based on the finite state machine, drive control software of complex driver layer was developed for cylinder recognition control of window observation. Finally, the engine starting test has been done on the engine test bench in order to verify the feasibility of cylinder recognition strategy. By using the cylinder recognition of checking window, the fastest detected two cam teeth can achieve cylinder recognition success in the ideal condition and the cylinder recognition time is 0.3s, in the worse condition the successful cylinder recognition takes 1.3 turn and the time is 0.5s. Besides the starting success rate and time is statistic and compared between the above two modes, by using cylinder recognition of checking window, the success rate of starting has been increased by more than 10%, reaching 100%, and the starting time has been shortened from 1.5s to within 1s. Above experimental results show that the strategy is effective and feasible. The achievement of this strategy not only improves the preferment of electronic control diesel engine in starting condition but also perfects the timing control of electronic control system. [ABSTRACT FROM AUTHOR]

Objective: Mucopolysaccharidosis type VI (MPS VI) or Maroteaux-Lamy syndrome is an autosomal recessive lysosomal storage disease caused by a deficiency of arylsulfatase B(ARSB), which is required in the degradation of dermatan sulfate and chondroitin sulfate. The deficiency of ARSB leads to an accumulation of dermatan sulfate and chondroitin sulfate in lysosomes and gross excretion in the urine.Few articles about clinical study and ARSB gene mutation analysis of Chinese MPS VI patients were published. This study aimed to explore the clinical features and characteristics of ARSB gene in Chinese children with MPS VI., Method: Thirteen children were diagnosed as MPS VI by ARSB enzyme activity determination during the period from 2009 to 2013. Their clinical features, radiological findings and urine glycosaminoglycan (GAG) levels were retrospectively reviewed. Direct sequencing was used to identify any mutation in the ARSB gene., Result: Thirteen children were diagnosed at the average age of (3.9 ± 2.2) years with 6 male and 7 female. All of these children presented with severe form and onset at an early age of (1.5 ± 0.8) years.Other clinical features included coarse facies, short stature, skeleton deformity, corneal clouding, hepatosplenomegaly with normal intelligence. The radiological findings in all children were characteristic of dysostosis multiplex, like abnormal development of vertebral bodies of the spine, campylorrhachia and paddle-shaped widened ribs. The MRI in case 2 showed cervical cord compression and multiple cysts degeneration in the corona radiate, cella lateralis and callosum.High urine GAG levels were detected, (307.10 ± 112.14) mg/L (Normally below 70 mg/L) and (722.28 ± 245.68) µg/mg creatinine. The ARSB enzyme activity in leukocytes was low, (13.29 ± 6.22) nmol/(mg×h) [Normal range (47-169) nmol/(mg×h)] by fluorogenic assay and (0.24 ± 0.18) U/g [Normal range (1.01-11.47) U/g] by colorimetric assay. A total of 11 mutations were identified by molecular analysis, including seven previously reported mutations (p.L72R, p.G167R, p.G303E, p.F399L, p. T442M, p.Y255X and p.R327X) and four novel mutations (p.Y175D, p.S403X, p.S464X and large deletion including ex. 2, 3). The c.1197C>G (p.F399L) mutation was the most common mutation in this study (31%)., Conclusion: The severe form of MPS VI is characterized by early onset and rapid illness progression. Both the radiological findings and increased urine GAG are important clues to diagnose MPS VI.Large decrease or absence of ARSB activity is diagnostic for MPS VI.Four novel mutations of ARSB gene were identified. The reported mutation c.1197C>G (p.F399L) was the hot-spot mutation in this study.

The present paper was aimed to study the relationship between the pneumonia clinical features and the pathogens of pneumonia in children by making use of association rules based on the clinical data of 6 300 cases of pneumonia. Through software analysis, the different association relationship can be obtained between different clinical features of pneumonia in children, such as gender, age and region, etc., and the pathogens of pneumonia. For example, children of different sex with the same pathogen showed different association relationships. Due to the different association relationships between the pneumonia clinical features and the pathogens of pneumonia in children of Guangzhou area, different methods in prevention and treatment of children's pneumonia should be adopted according to actual condition, in order to achieve the best results.

Objective: We report two cases of Turner syndrome with a female phenotype and a 45,X(22)/46,XY(88) karyotype. The relevant literatures in relation to the incidence, pathogenesis, clinical manifestations and managements of Turner syndrome with a 45,X/46,XY karyotype were reviewed.