Abacterial strain A25, isolated from activated sludge and identified as Bacillius megaterium, could produce flocculant, The optimum carbon and nitrogen sources are maltose and yeast extract, respectively. The optimum pH range is 7.0～10.0. The flocculant was synthesized during the cell growth. The flocculant mainly exists in the supermatant. The partial purified flocculant could be kept in 60C for 1 hour without losing activity.

Spreaded and immobilized the bacterial cells entraped in PVA on pieces of cotton cloth as porous carrier. The conditions for preparing immobilized cells were as below: cell concentration, 20 mg wet weight/ml; PVA concentration, 5%; spreading amount, 0.3ml/cm~2; immobilization for 12 hours in saturated boron acid solution. Then activated the immobilized cells in buffer containing dyes. Thus, immobilized cells with high decolorizing activity were obtained.In columns packed with immobilized cells, the decolorization efficiencies of continuous influent and intermissional influent were compared with each other. In twenty days, the decolorization rates were both higher than 90%; then the decolorization rate of continuous influent decreased to about 60% after 60 days while it still reached 80% in case of intermissional influent. The efficiency of the later was distinct higher than that of the former.

BACKGROUND: Retinitis pigmentosa(RP) is a group of commonest genetic blindness-inducing eyeground diseases, which have relative great heterogenicity in both heredity and phenotype. Pierce et al discovered a new retinal photoreceptor cell specific gene-RP1 in 1999, and also found in their following research that the mutation of this gene can induce autosomal dominant RP(adRP) . Present RP1 molecular genetic researches mainly concentrate in Caucasians.OBJECTIVE: To investigate the mutation frequency, characteristics of RP1gene in Chinese RP patients and its role in RP pathogenesis.DESIGN: A comparative study by employing RP patients as subjects and healthy individuals as control.SETTING: Gene diagnosis and therapy center in a hospital affiliated to a military medical university of Chinese PLA.PARTICIPANTS: Totally 101 RP patients without genetic classification were visited patients of the outpatient Department of Ophthalmology of Hong Kong Prince Wales Hospital and Hong Kong Hospital of Ophthalmology between January 1998 and December 2001, which aged between 10 and 79years old(including 43 male and 58 female cases) with an average age of 40years old. Inclusive criteria: Cases who were in accordance with the general national and international standards for RP diagnosis(including funduscope observation and electroretinogram test). Exclusive criteria: patients of other retinal pathological changes. A total of 190 healthy adults were selected in control group, which had no RP family history and no RP or other eye diseases in eye examination, for the confirmation of whether the detected variation was the polymorphism of RP1 gene.METHODS: Totally 101 cases received conformation sensitive electrophoresis(CSGE) and DNA direct sequencing analyses to detect the point mutation in entire RP1 gene encoding range.MAIN OUTCOME MEASURES: Mutation frequency and patterns of RP1gene in Chinese RP patients and its role in RP pathogenesis.RESULTS: The mutation detectable rate of RP1 gene in all PR patients was 1/101. Mutation ultimately caused serious truncation in RP1 protein. The phenotype of the disease might be originated from functional deficiency in PR1protein synthesis. In addition, 10 missense mutations were found in our study population, most of which were RP1 gene polymorphism except the unconfirmed pathological significance of M479I.CONCLUSION: The deletion of corresponding segments(codon 1052-1933) in RP1 protein would induce RP. Large-scale RP1 genotying is necessary, which also can discover more RP-inducing mutation and RP1 gene polymorphism different from other races simultaneously for further fundamental therapy of RP and thorough improvement of the quality of life of the patients.

Objective To understand the cognition about healthcare-associated infection(HAI) management among directors in secondary and above hospitals in Shaanxi Province.Methods Questionnaire survey was adopted to investigate hospital directors who participated in The third session of Shaanxi Provincial HAI management training course for hospital directors.Results A total of 181 questionnaires were distributed, 173 (95.58％) were qualified.74.57％ of surveyed hospitals were secondary hospitals, 61.85％ were comprehensive hospitals, 67.05％ of respondents received HAI training in recent 3 years, 81.50％ and 55.49％ of hospital directors thought the main factors influencing the HAI management were health care workers'' awareness on HAI and leaders'' attention respectively.58.96％, 60.12％, and 46.82％ of hospital directors thought the director of HAI management department should have intermediate and above professional title, bachelor degree or above education, and preventive medicine professional requirements respectively.The awareness rate of HAI management-related knowledge was 86.71％, difference in awareness rate of HAI management-related knowledge among respondents of different job, gender, and HAI training in recent 3 years were all significantly different(all P<0.05).Conclusion Hospital directors'' cognition on HAI management affect the development of HAI work, strengthen the training on HAI knowledge among administrators can improve hospital administrators'' awareness on HAI prevention and control.

Objective To understand current situation of full-time healthcare-associated infection(HAI)manage-ment staff in hospitals in Xianyang,explore the causes of instability of HAI management team.Methods Stratified random sampling method was adopted,hospitals were divided into secondary and tertiary levels,then numbered ac-cording to different levels,surveyed hospitals were selected randomly,general condition,professionals,and causes of instability of 52 selected full-time HAI management staff members in 29 secondary and above hospitals in Xian-yang were surveyed.Results Full-time HAI management staff were mainly women,accounting for 89.13%;54.35% of staff were aged 30-50 years;47.83% had bachelor degree and above;41.30% had intermediate profes-sional titles;65.22% were nurses;91.30% engaged in HAI management for <9 years;HAI management staff were statistically different in age and education level(both P<0.05).63.04% of full-time HAI management staff engaged in nursing before engaging in HAI management work;63.04% engaged in HAI management work accord-ing to administrative arrangement,the top three causes for instability of HAI management team were heavy work-load(91.30%),lacking enough attention of leaders(78.26%),and low pay(63.04%).Conclusion Structure of HAI management full-time staff in hospitals in Xianyang is irrational,the main causes for unstable management team is heavy workload,insufficient attention paid by leaders,and low pay.

Objective: To investigate blood-borne occupational exposure and related protection in the medical staff of a traditional Chinese medicine hospital, and to provide a reference for reducing the risk of blood-borne occupational exposure. Methods: Forty-eight medical workers with blood-borne occupational exposure in 2015 were selected to analyze the incidence of blood-borne occupational exposure, influencing factors, operations that caused blood-borne occupational exposure, pathogens, and occupational protection. Results: The incidence rate of blood-borne occupational exposure in the medical staff of the traditional Chinese medicine hospital in 2015 was 3.30% (48/1 455) , and the frequency was 0.04 time/person/year. The workers with blood-borne occupational exposure were mostly nurses, females, workers aged <30 years, workers with <5 working years, and workers with a junior professional title. There was a significant difference in the incidence rate of blood-borne occupational exposure between workers with different ages and working years. The main way of blood-borne occupational exposure was sharp injury (96.08%) . The main operations that caused blood-borne occupational exposure were covering or separating the syringe needle after injection and disposing used sharp instruments. The main exposure site was the hand (96.08%) , with the thumb and index finger for the left hand and the middle finger and index finger for the right hand; there was no significant difference in the exposure site distribution between the two hands (P<0.05) . The main pathogen that caused blood-borne occupational exposure was hepatitis B virus (68.96%) . The rate of correct local treatment for blood-borne occupational exposure was 88.24%. The rate of prophylactic medication was 74.51%, and hepatitis B immunoglobulin (HBIG) plus hepatitis B vaccine was the main way, followed by HBIG. In all workers with blood-borne occupational exposure, 62.74% did not wear gloves. Conclusion The medical workers with few working years have a high risk of blood-borne occupational exposure, so the training on protection against blood-borne occupational exposure should be strengthened to reduce the risk of blood-borne occupational exposure and infection.

Objective: To understand the status and related knowledge requirements of health emergency literacy among college students in Shaanxi Province, so as to provide the basis for improving college students health emergency literacy. Methods: A total of 2 723 students from 18 colleges and universities in Shaanxi Province were selected by multi stage random sampling and simple random sampling methods in November 2023, and the survey of health literacy in emergency and knowledge requirements of health emergency literacy was conducted. Statistical analysis was carried out by using χ 2 test, Wilcoxon rank sum test, Kruskal-Wallis H test and Logistic regression analysis. Results: About 28.98% of the surveyed college students had a high level of health emergency literacy, which varied by students whether being only one child, whether having left behind experience, with different personality types, whether being student cadres, and with different frequencies of community or social activities ( χ 2=9.15, 7.90, 32.73, 16.29 , 120.25, P <0.05). The equivalence scores of the four dimensions of health emergency literacy from high to low were poisoning and nuclear and radiation (0.84), medical rescue (0.83), infectious disease (0.82), and basic knowledge and behavior ( 0.77 ). Logistic regression analysis found that college students with left-behind experience were negatively correlated with health emergency literacy and its four dimensions ( OR =0.74, 0.72, 0.80, 0.80, 0.83), while personality type (rational type), community or social activity frequency were positively correlated with the cognitive levels of health emergency literacy and its four dimensions among college students ( OR =1.57, 1.50, 1.33, 1.27, 1.38)( P <0.05). There was a higher level of basic knowledge and behavioral cognition among only child college students ( OR =3.73), and female students had a higher level of health emergency literacy, as well as awareness of infectious disease outbreaks and medical rescue ( OR =1.21, 1.28, 1.21)( P <0.05). The radar map showed that the level of health emergency literacy was positive development radar map. About 67.68 % of the students had a high willingness to acquire health emergency literacy knowledge, and the demand for basic health emergency knowledge and behavioral knowledge was the highest (52.37%). Conclusions College students have insufficient health emergency literacy, but they have the highest demand for health emergency. Publicity and education should be strengthened for students with left behind experience, irrational type, and low frequency of community or social activities.

Objective To investigate the changes of cortical thickness and relative resting state functional connectivity in patients with generalized anxiety disorder (GAD).Methods The present study analyzed structural and eyes-open resting state functional MRI were performed in 21 patients with GAD and 22 matched healthy controls.Cortical thickness was estimated with FreeSurfer.The structurally altered regions were defined as region of interest (ROI) to analyze functional connectivity (FC) using resting state functional MRI data by DPABI.Results Cortical thickness of patients with GAD were increased in right rostral middle frontal gyrus (rMFG;MNI:x =27.9,y =53.4,z =-11.1;size:241.93 mm2;FDR corrected,P ＜ 0.1) and right inferior temporal gyrus (IGT;MNI:x =49.7,y =-57.8,z =-8.7;size:138.93 mm2;FDR corrected,P＜0.1) compared with healthy controls.FC between right rMFG and right superior/middle occipital gyrus as well as well as FC between rMFG and right precentral gyrus showed decreased in patients with GAD compared with healthy controls(AlphaSim corrected,P＜0.05).FC between right rMFG and right angular gyrus showed increased in patients with GAD compared with healthy control (AlphaSim corrected,P＜0.05).Conclusion The rMFG may play an important role in the pathophysiology of GAD,which can be used as an stimuli target in physicotherapeutics to improve anxiety symptoms.