[Design of airborne dual channel ultraviolet-visible imaging spectrometer with large field of view, wide spectrum, and high resolution].

The ultraviolet-visible (UV-Vis 200-500 nm) imaging spectrometer is an important part of space remote sensing. Based on special requirements and practical application of the airborne UV-VIS spectrometer, a kind of scanning imaging spectrometer using area array CCD is proposed, which can meet the application requirements of large field of view, wide spectrum and high resolution. It overcomes low spatial resolution of traditional line array CCD scanning imaging spectrometer, and limited field of view of the pushbroom imaging spectrometer. In addition, dual channel was designed to reduce stray light. 400-500 nm band includes two order spectrum for 200-250 nm band, and variation of radiance from earth between the shorter wavelength (<290 nm) and the longer wavelength (>310 nm) is above three orders of magnitude. In the structure design of the system, the imaging spectrometer is composed of a two-mirror concentric telescope and two Czerny-Turner plane grating imaging spectrometers. The whole system doesn't use any additional optical elements in addition to spherical mirrors. The whole system has the advantage of simple structure, excellent performance, and very good feasibility. The modulation transfer function value of full spectrum and full field of view is above 0.6.

[Promoting of angiogenesis and osteogenesis in radial critical bone defect regions of rabbits with nano-hydroxyapatite/collagen/PLA scaffolds plus endothelial progenitor cells].

OBJECTIVE: To explore the roles of nano-hydroxyapatite/collagen/PLA (nHAC/PLA) plus endothelial progenitor cells (EPCs) in repairing segmental bone defects of rabbit radius and enhancing angiogenesis and new bone formation. METHODS: EPCs isolated from New Zealand white rabbit bone marrow were cultured, identified and seeded into nHAC/PLA scaffolds. And the growth of EPCs in scaffolds was observed under scanning electron microscopy (SEM). Thirty-six were randomly divided into 3 groups to establish segmental bone defect models in radii. Two groups were implanted with EPCs/scaffolds constructs (group A, n = 16) and scaffolds alone (group B, n = 16) respectively. The remaining four rabbits were used as negative control (group C) and nothing was implanted. Animals were sacrificed at different timepoints and radii harvested to undergo radiological examination, histological examination and microvessle density test. RESULTS: These cells isolated from bone marrow were confirmed as EPCs. SEM showed that EPCs attached to the nHAC/PLA scaffolds, grew and proliferated well. Animal experiments revealed that radiological scores (5w: 2.25 ± 0.50 vs 1.00 ± 0.00; 10w: 2.75 ± 0.50 vs 1.75 ± 0.50; 15w: 4.25 ± 0.50 vs 3.0 ± 0.0; each P < 0.05), percentage of new bone formation area in bone defect regions (5w: 29.0% ± 3.5% vs 8.1% ± 0.8%; 10w: 63.4% ± 5.5% vs 16.6% ± 1.3%; 15w: 96.0% ± 4.3% vs 34.0% ± 6.6%; each P < 0.05) and microvessel density (2w: 13.5 ± 0.9 vs 4.3 ± 1.0; 5w:9.8 ± 0.7 vs 4.8 ± 0.3; 10w: 7.0 ± 0.4 vs 4.5 ± 0.4; each P < 0.05) in group A were significantly higher than those in group B. No new bone formation occurred in group C. CONCLUSION: The composite structure of EPCs-nHAC/PLA can enhance angiogenesis and new bone formation in segmental bone defects in rabbit radii. It may become a potential candidate of promoting revascularization of tissue engineering bone and repairing large bone defects.

[Risk assessment of H5N1 human infection after an outbreak of avian influenza in water fowl].

OBJECTIVE: To evaluate the risk of human infection after the outbreak of avian influenza H5N1 in animals, and probe the possibility for virus transmission. METHODS: By means of field epidemiological study, molecular epidemiology, serology and emergency surveillance, persons who had ever closely contacted with sick or dead poultry were observed. While, the RT-PCR and gene sequencing method were used to detect H5 nucleic acid from environmental swabs from 4 epidemic spots, and hemagglutination inhibition assay was also used to detect H5 antibody. RESULTS: Of 22 environmental swabs detected from 4 epidemic spots, one was positive for H5 nucleic acid, and the homogeneity was 95.9% as compared with H5N1 virus A/China/GD01/2006 (H5N1) found in Guangzhou in 2006 by gene sequence analysis. 62 environmental swabs from live poultry stalls of food markets near epidemic spot were detected negative. Six of 68 blood samples of contacts were positive for H9 antibody, and all were negative for H5 antibody. 68 throat swabs of contacts were detected negative for H5 nucleic acid. No close contact was found abnormal after 7 days medical observation. 337 influenza-like cases were reported in emergency surveillance, and no suspicious case was found. CONCLUSION: The current outbreak of H5N1 avian influenza in water fowls has not yet caused further transmission, and human avian influenza case has not been observed. It indicates that the ability of H5N1 virus to transmit to human is not strong yet, and the risk of human infection for H5N1 is still low.

[Needs on information related to influenza pandemic by the public].

OBJECTIVE: To understand the information needs on human infection with avian influenza (H5N1), A (H1N1) and influenza pandemic in different time periods and create well-targeted messages by the public, so as to develop communication with the public effectively when human infection with avian influenza (H5N1), A (H1N1) and influenza pandemic occur. METHODS: Data were collected through questionnaire over telephone calls. The questionnaire was self-designed, revised after pilot testing. RESULTS: The effective response rate in this telephone survey was 54.33%, higher than those in Beijing and Shanghai. The respondents felt that government's propaganda during the influenza virus-active period was more helpful and instructive than those in the period when influenza was relatively inactive (chi(2) = 17.41, P = 0.000). Trust to the government by the public was higher in the influenza virus-active than in the relatively inactive period (chi(2) = 8.15, P = 0.004). As to the information needs, the respondents reflected that during the time period of relative influenza inactivity, they viewed the basic knowledge of human infection with avian influenza (H5N1) as their top priority, while in the influenza virus-active period, the feasible preventive measures was their top priority. The pandemic-related information needs in the influenza virus-active period and in the time period of relative influenza inactivity were similar, demonstrating that the respondents had no perceptual knowledge of influenza pandemic and had poor awareness on the pandemic. The respondents were not used to wear a mask to cover their mouths and noses when sneezing, but were quite knowledgeable about the following preventive measures as: avoid going out and at the crowded areas, wash hands frequently etc. Around 2% to 6% of the respondents did not have any information needs. CONCLUSION: The response rate in this telephone survey was fairly high, indicating that telephone survey was well accepted by Guangzhou residents. The public was satisfied with the government's propaganda activities and trusting the government. Public health professionals should develop communication messages closely related to the epidemic situation to target the information needs from the public.

[Epidemiological study on injuries among children in Beijing].

OBJECTIVE: To explore the morbidity, burdens caused and risk factors of injuries among children and to provide information for policy making on prevention. METHODS: By PPS sampling method, we selected 28 000 households in Beijing and using a questionnaire developed by UNICEF, TASC and China CDC. RESULTS: The morbidity of child injury in Beijing was 2.25%, higher than that of adults (1.56%) with 6-9 year group the highest (2.83% ). The morbidity of boys was 3.04% higher than that of girls (1.37%). Among the 7 death cases, 3 were caused by injury(2 RTA, 1 drowning). The three leading causes of injuries were fall, animal bite and road traffic accident in children. Among children aged 0-5 years, fall, animal and burn/machine injuries were the leading causes. Among children aged 0-5 years, the leading causes were hurt by animals, fall and RTA with the leading causes as fall, sprain and RTA. The average medical cost of injury cases was 1617.57 Yuan. There were 3500 children (injured orphan) whose parents were injured leading to death or disability in Beijing in 2003. CONCLUSION: Injury was the leading cause of child deaths in Beijing with children of 6-9 years old having the highest morbidity with RTA the most severe type of injuries in Beijing which affects both children and their parents.