Characteristics and Analysis of Swine Streptococcosis Incidence in Binzhou Region in 2013

To fully understand swine stroptococcosis in Binzhou and surrounding areas, we studied its incidence rate and incidence characteristics in 2013, in order to put forward constructive suggestions for scientific prevention and control of swine streptococcosis. Isolation and purification, biochemical and molecular biolo- gy identification and drug susceptibility test of Streptococcus suis were carried out, and mixed infection of S. suis with classical swine fever virus, pseudorabics virus and porcine circovirus virus was statistically analyzed. The results showed that 46 strains of S. suis were screened, and the positive rate was approximately 24.9%, with high degree of resistance and multiple resistances. S. suis had different degrees of mixed infection with classical swine fever virus, pseudorabics virus and porcine cireovirus virus, and the total mixed infection rate was 58.7%.

Infection Characteristics and Interaction of Three Species of Penicillium in the Postharvest Storage of‘Gonggan'Mandarin(Citrus reticulata)

[Objectives]This study was conducted to understand the infection characteristics of Penicillium on‘Gonggan’mandarin(Citrus reticulata)and its effects on postharvest storage quality.[Methods]Nine inoculation treatments were designed and tested for the three identified Penicillium species,namely:three single inoculation experiments,four compound inoculation experiments,and two controls without inoculation.After treatment,the fruit was put into plastic film fresh-keeping bags and stored at a natural room temperature.The determined and analyzed indexes included fruit disease incidence,disease index,disease symptoms,disease spot expansion speed and weight loss rate,soluble solid content and organic acid content in different inoculation treatments.[Results]All‘Gonggan’fruit inoculated with Penicillium were diseased 2 d after inoculation,and completely rotted 14 d later.Of the three Penicillium species isolated and identified,Penicillium digitorum and its combinations were the most harmful to‘Gonggan’fruit.The hazard of Penicillium italicum was equal to or even weaker than that of Penicillium expansum.Eventually,P.digitorum dominated when coexisting on the same fruit.Different species of Penicillium obviously showed competition and antagonism in the process of growth and infection,especially for P.digitorum which was stronger,but other two species of Penicillium also had obvious self-protection ability.Low-temperature storage played a crucial role in the preservation of‘Gonggan’fruit,because it could significantly inhibit Penicillium infestation,and suppress fruit weight loss and the reduction of the contents of soluble solids and organic acids.[Conclusions]The infection characteristics and interaction relationship of Penicillium in the postharvest storage of‘Gonggan’fruit were revealed.

Sound absorption characteristics of microperforated absorbers for random incidence

Based on previous work on 'Statistical absorption coefficient of microperforated absorbers', in which it was shown that theoretical results agree well with experiments on the absorption characteristics of microperforated absorbers (MPA) for random incidence. Further work was carried out in this investigation of the statistical absorption coefficients of MPA in random fields by computation, in order to find the best. structure of MPA. It is established that ordinarily the absorption curves of MPA for random incidence and that for normal incidence are quite alike, only that the absorption coefficients are more or less reduced and the whole curve is shifted to higher frequencies without any change of shape. But when the perforate constant k = d ωρ0/4η where d is the diameters of perforations in mm and f0, the absorbers resonance frequency is reduced below 2, say, secondary absorption bands start to play more important role. Pretty soon, they merge with the main absorption band and form a long tail of the latter,extending the absorption far into high frequencies, raising the resulting absorption band to three, four or more octaves. The behavior of the secondary absorption bands is discussed.

CLINICOPATHOLOGICAL ANALYSIS OF 5785 CASES WITH RESPIRATORY SYSTEM TUMORS

Objective; To study the characteristics and tendency of incidence of patients with respiratory system tumors during the past 23 y in Tianjin. Methods： All data in our research was obtained from the surgical pathology files of Department of Pathology of the general and the Second Hospitals of Tianjin Medical University between 1981 and 2003. All data was analyzed by Spss 11.5 statistics program. The comparisons were made by u-test, P〈0.05 was considered as significant. Results： 1. The detection rate of malignant tumors is significantly higher than that of benign tumors （U=52.68, p=0.000） in respiratory system. 2. The common sites of benign tumors are nose and pharynx, but the common sites of malignant tumors are lung and larynx. 3. The incidence of benign tumors generally peaks between the ages of 40 and 50, but the incidence of malignant tumor generally peaks between the ages of 50 and 60. 4. The commonest histological type of malignant tumors is squamous cell carcinoma, but the commonest histological type of benign tumors is papilloma. 5. The detection rate of malignant lung tumors steadily increased between 1981 and 1999 and increased sharply from 1999 to 2003, but the detection rate of malignant Nasopharyngeal tumors steadily decreased from 1981 to 2003. Between 1981 and 1997, the detection rate of malignant laryngeal tumors steadily increased, followed by a decrease between 1997 and 2003. Conclusion： The detection rate of malignant respiratory system tumors especially lung cancer is gradually increasing. Therefore early prevention and treatment are critical to patients＇ prognosis.