Robot Grasp Planning: A Learning from Demonstration-Based Approach.

Robot grasping constitutes an essential capability in fulfilling the complexities of advanced industrial operations. This field has been extensively investigated to address a range of practical applications. However, the generation of a stable grasp remains challenging, principally due to the constraints imposed by object geometries and the diverse objectives of the tasks. In this work, we propose a novel learning from demonstration-based grasp-planning framework. This framework is designed to extract crucial human grasp skills, namely the contact region and approach direction, from a single demonstration. Then, it formulates an optimization problem that integrates the extracted skills to generate a stable grasp. Distinct from conventional methods that rely on learning implicit synergies through human demonstration or on mapping the dissimilar kinematics between human hands and robot grippers, our approach focuses on learning the intuitive human intent that involves the potential contact regions and the grasping approach direction. Furthermore, our optimization formulation is capable of identifying the optimal grasp by minimizing the surface fitting error between the demonstrated contact regions on the object and the gripper finger surface and imposing a penalty for any misalignment between the demonstrated and the gripper's approach directions. A series of experiments is conducted to verify the effectiveness of the proposed algorithm through both simulations and real-world scenarios.

Robot Programming from a Single Demonstration for High Precision Industrial Insertion.

We propose a novel approach for robotic industrial insertion tasks using the Programming by Demonstration technique. Our method allows robots to learn a high-precision task by observing human demonstration once, without requiring any prior knowledge of the object. We introduce an Imitated-to-Finetuned approach that generates imitated approach trajectories by cloning the human hand's movements and then fine-tunes the goal position with a visual servoing approach. To identify features on the object used in visual servoing, we model object tracking as the moving object detection problem, separating each demonstration video frame into the moving foreground that includes the object and demonstrator's hand and the static background. Then a hand keypoints estimation function is used to remove the redundant features on the hand. The experiment shows that the proposed method can make robots learn precision industrial insertion tasks from a single human demonstration.

Nutrient Deficiency and an Algicidal Bacterium Improved the Lipid Profiles of a Novel Promising Oleaginous Dinoflagellate, Prorocentrum donghaiense, for Biodiesel Production.

The lipid production potentials of 8 microalgal species were investigated. Among these 8 species, the best strain was a dominant bloom-causing dinoflagellate, Prorocentrum donghaiense; this species had a lipid content of 49.32% ± 1.99% and exhibited a lipid productivity of 95.47 ± 0.99 mg liter-1 day-1, which was 2-fold higher than the corresponding values obtained for the oleaginous microalgae Nannochloropsis gaditana and Phaeodactylum tricornutum. P. donghaiense, which is enriched in C16:0 and C22:6, is appropriate for commercial docosahexaenoic acid (DHA) production. Nitrogen or phosphorus stress markedly induced lipid accumulation to levels surpassing 75% of the dry weight, increased the C18:0 and C17:1 contents, and decreased the C18:5 and C22:6 contents, and these effects resulted in decreases in the unsaturated fatty acid levels and changes in the lipid properties of P. donghaiense such that the species met the biodiesel specification standards. Compared with the results obtained under N-deficient conditions, the enhancement in the activity of alkaline phosphatase of P. donghaiense observed under P-deficient conditions partly alleviated the adverse effects on the photosynthetic system exerted by P deficiency to induce the production of more carbohydrates for lipogenesis. The supernatant of the algicidal bacterium Paracoccus sp. strain Y42 culture lysed P. donghaiense without decreasing its lipid content, which resulted in facilitation of the downstream oil extraction process and energy savings through the lysis of algal cells. The Y42 supernatant treatment improved the lipid profiles of algal cells by increasing their C16:0, C18:0, and C18:1 contents and decreasing their C18:5 and C22:6 contents, which is favorable for biodiesel production. IMPORTANCE This study demonstrates the high potential of Prorocentrum donghaiense, a dominant bloom-causing dinoflagellate, for lipid production. Compared with previously studied oleaginous microalgae, P. donghaiense exhibit greater potential for practical application due to its higher biomass and lipid contents. Nutrient deficiency and the algicidal bacterium Paracoccus sp. strain Y42 improved the suitability of the lipid profile of P. donghaiense for biodiesel production. Furthermore, Paracoccus sp. Y42 effectively lysed algal cells, which facilitates the downstream oil extraction process for biodiesel production and results in energy savings through the lysing of algal cells. This study provides a more promising candidate for the production of docosahexaenoic acid (DHA) for human nutritional products and of microalgal biofuel as well as a more cost-effective method for breaking algal cells. The high lipid productivity of P. donghaiense and algal cell lysis by algicidal bacteria contribute to reductions in the production cost of microalgal oil.

Algicidal Activity of Novel Marine Bacterium Paracoccus sp. Strain Y42 against a Harmful Algal-Bloom-Causing Dinoflagellate, Prorocentrum donghaiense.

Prorocentrum donghaiense blooms occur frequently in the Yangtze River estuary and the adjacent East China Sea. These blooms have damaged marine ecosystems and caused enormous economic losses over the past 2 decades. Thus, highly efficient, low-cost, ecofriendly approaches must be developed to control P. donghaiense blooms. In this study, a bacterial strain (strain Y42) was identified as Paracoccus sp. and was used to lyse P. donghaiense The supernatant of the strain Y42 culture was able to lyse P. donghaiense, and the algicidal activity of this Y42 supernatant was stable with different temperatures and durations of light exposure and over a wide pH range. In addition to P. donghaiense, Y42 showed high algicidal activity against Alexandrium minutum, Scrippsiella trochoidea, and Skeletonema costatum, suggesting that it targets primarily Pyrrophyta. To clarify the algicidal effects of Y42, we assessed algal lysis and determined the chlorophyll a contents, photosynthetic activity, and malondialdehyde contents of P. donghaiense after exposure to the Y42 supernatant. Scanning electron microscopy and transmission electron microscopy analyses showed that the Y42 supernatant disrupted membrane integrity and caused algal cell breakage at the megacytic zone. Photosynthetic pigment loss and significant declines in both photosynthetic efficiency and the electron transport rate indicated that the Y42 supernatant damaged the photosynthetic system of P. donghaiense Malondialdehyde overproduction indicated that the Y42 supernatant caused lipid peroxidation and oxidative damage to membrane systems in the algal cell, ultimately leading to death. The findings of this study reveal the potential of Y42 to remove algal cells from P. donghaiense blooms.IMPORTANCEP. donghaiense is one of the most common dinoflagellate species that form harmful algal blooms, which frequently cause serious ecological pollution and pose health hazards to humans and other animals. Screening for bacteria with high algicidal activity against P. donghaiense and studying their algicidal processes and characteristics will contribute to an understanding of their algicidal effects and provide a theoretical basis for preventing algal blooms and reducing their harm to the environment. This study reports the algicidal activity and characteristics of Paracoccus against P. donghaiense The stability of the algicidal activity of Paracoccus in different environments (including different temperature, pH, and sunlight conditions) indicates its potential for use in the control of P. donghaiense blooms.

Serum prealbumin is a predictive biomarker for stroke-associated infection after an ischemic stroke.

BACKGROUND: Several prior studies have linked serum prealbumin (PA) as a predictor for perioperative infection. However, whether peripheral blood PA levels can be used as an indicator of stroke-associated infection (SAI) is still unclear. In this study, we attempt to find whether serum PA is a meaningful predictor in SAI after an ischemic stroke, so as to provide theoretical basis for clinical treatment. METHODS: Consecutive patients with acute ischemic stroke who were admitted to our hospital were enrolled and serum PA was collected. A prospective study was conducted to observe the predictive value of PA in the SAI incident in ischemic stroke patients. RESULTS: Of 104 patients, 29 (27.9%) developed an SAI after 7 d of follow-up. The stroke with SAI group had significantly lower PA levels than the stroke without SAI group ( p < 0.05). The optimal cutoff value for predicting SAI was PA ≤ 191 mg/L, with sensitivity and specificity of 58.62% and 81.33%, respectively. Kaplan-Meier survival analysis showed that stroke patients with low serum PA level (PA ≤ 191 mg/L) had a higher SAI rates (log-rank test, χ2 = 16.870, p < 0.001). Cox regression analysis showed that PA ≤ 191 mg/L (hazard ratio = 3.207; 95% CI, 1.430-7.190, p = 0.005) was an independent risk factor for SAI. CONCLUSIONS: Early detection of serum PA during the acute phase of ischemic stroke may help us to identify at-risk SAI patients, and hence rapidly guide the intervention to prevent SAI.

Circular RNA expression alterations are involved in OGD/R-induced neuron injury.

Cerebral ischemia-reperfusion injury (IRI) is a common clinical pathological process, and it is a key step in causing further ischemic organ damage. The mechanism of cerebral IRI is still not fully understood, leading to a lack of effective treatment. It has been demonstrated that circular RNAs (circRNAs) can act as miRNA sponges and play an important role in regulating gene expression through a circRNA-miRNA-gene pathway. The specific role of circRNAs in the pathogenesis of cerebral IRI, however, is still unclear. Thus, in the present study, we investigated circRNA expression differences in HT22 cells with oxygen-glucose deprivation/reoxygenation (OGD/R) versus normal controls. The results from circRNA microarrays revealed that 15 circRNAs were significantly altered in the OGD/R model (p < 0.05) compared with the control group. Among them, 3 were significantly up-regulated, and the other 12 were down-regulated. Furthermore, the up-regulated expression of mmu-circRNA-015947 was verified using quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatics analysis revealed that up-regulated expression of mmu-circRNA-015947 could interact with miRNAs (mmu-miR-188-3p, mmu-miR-329-5p, mmu-miR-3057-3p, mmu-miR-5098 and mmu-miR-683) and thereby enhance target gene expression. KEGG pathway analysis predicted that mmu-circRNA-015947 may participate in apoptosis-related, metabolism-related and immune-related pathways, which are known to be involved in the pathogenesis of IRI. This research suggests that the overlapping expression of mmu-circRNA-015947 might be involved in the process of cerebral IRI and presents a novel molecular target for clinical therapy.

Neuromyelitis optica spectrum disorders may be misdiagnosed as Wernicke's encephalopathy.

PURPOSE: To raise doctors' attention to the differential diagnosis of neuromyelitis optica spectrum disorders (NMOSD) and Wernicke's encephalopathy (WE). PATIENTS AND METHODS: We extensively reviewed the medical records of 136 patients who had visited our hospital since 2008 and were suspected of having central nervous system demyelinating diseases. Four of those patients had somnolence, electrolyte imbalance and brain lesions around the third ventricle and were included in the study. We tested the serum of the four patients for the presence of aquaporin-4 (AQP4) M23 antibody. RESULTS: All the four patients had positive AQP4 antibody in their serum. Two of the patients were misdiagnosed as WE before AQP4 antibody detection occurred. CONCLUSIONS: NMOSD and WE have similar brain lesion locations, histopathological changes and clinical manifestations. It is important to distinguish NMOSD from WE by detecting AQP4 antibody in serum or cerebral spinal fluid. Vitamin B1 should also be administered to the patients who have a history of thiamine deficiency.

Dynamic change in magnetic resonance imaging of patients with neuromyelitis optica.

OBJECTIVE: To analyze changes in magnetic resonance imaging (MRI) of spinal cord lesions in neuromyelitis optica (NMO) and the correlation between segmental length of spinal cord lesions and expanded disability status scale (EDSS) scores. METHODS: Twenty-five patients with confirmed NMO were examined from the Second Affiliated Hospital of Guangzhou Medical University, China. The information collected included their treatment, MRI, laboratory tests, and EDSS scores at different stages. RESULTS: All cases exhibited spinal cord lesions, with 23 (92%) having longitudinally extensive transverse myelitis (extending ≥3 vertebral segments). There was a positive correlation between segmental length of spinal cord lesions and EDSS scores: during the acute phase, r = 0.430 (P = 0.032); during remission, r = 0.605 (P = 0.002). Enlarged spinal cord lesions and swelling were found in 18 cases (72%) during the acute phase, and 4 cases (16%, P = 0.000) after 6 months of treatment. Lesion enhancements were found in 17 cases (68%) during the acute phase, and 8 cases (32%, P = 0.023) after 6 months of treatment. Leptomeningeal enhancement was found in three cases during the acute phase, which disappeared after treatment. Atrophy of spinal cord lesions occurred in two cases. Change in lesions was statistically significant (P = 0.006) after 12 months of treatment. CONCLUSION: Positive correlation was found between segmental length of spinal cord lesions and EDSS scores, which was more significant during remission. After 6 months of regular treatment, restorative changes compared with the acute phase were found by MRI.

No Overlap among Serum GAD65, NMDAR and AQP4 Antibodies in Patients with Neuromyelitis Optica Spectrum Disorders.

OBJECTIVE: To evaluate whether serum glutamic acid decarboxylase (GAD), N-methyl-D-aspartate-receptor (NMDAR), and aquaporin-4 (AQP4) autoantibodies coexist in patients with neuromyelitis optica (NMO)/NMO spectrum disorders (NMOSD). METHODS: Serum samples were collected from 98 patients with NMO/NMOSD. Serum GAD65, NMDAR and AQP4 antibodies were measured using a cell-based assay. RESULTS: A total of 63 patients (64.3%) had myelitis and optic neuritis and satisfied the revised diagnostic criteria for NMO. Longitudinally extensive transverse myelitis was seen on spinal cord magnetic resonance imaging, showing continuous T2-weighted signal abnormalities in at least three vertebral segments in 26 patients (26.5%); 5 patients (5.1%) had recurrent optic neuritis, and 4 patients (4.1%) had brain syndromes with optic neuritis and myelitis. None of the 98 patients had diabetes, stiff-man syndrome, or epilepsy. All 98 patients tested positive for AQP4 antibody. No patients tested positive for GAD65 and NMDAR antibodies. CONCLUSIONS: In the present study, we found no simultaneous presence of serum GAD65, NMDAR and AQP4 antibodies in patients with NMO/NMOSD.

[Prevalence survey of using characteristics of quality, quantity, origin and composition claims on food labels in China].

OBJECTIVE: To understand the using characteristics of quality, quantity, origin and composition claims on food labels in China. METHODS: To get the label samples from different size of supermarket by taking photos in Beijing, and also samples were provided by provincial quality technical supervision, et al. Then extracted the claims from the label samples, classified the samples by determined food categories, and analyzed the using characteristics of these claims. RESULTS: The constituent ratio of quality, quantity, origin and composition claims were 29.48%, 2.24%, 29.21%, 31.81% among all the samples. The constituent ratio of snacks (16.11%) was maximum among all the samples using quality claims, and grain and its products (36.00%) for quantity claims, meat and meat products (22. 09%) for origin claims, snacks (27.04%) for composition claims. "Nature, Natural" (48.63%) was the most used claims among all the samples using quality claims, "Exaggerated capacity" (44.00%) was the most for quantity claims, "Product of , From, Manufactured in" (34.36%) was the most for origin claims, and "Pure, 100% , All" (38.03%) was the most for composition claims. CONCLUSION: The using of quality, quantity, origin, and composition claims is frequently on food labels in China, and a lot of studies should be taken on this field, government should also enact regulations to regulate the use of this claims.

[Expert investigation on food safety standard system framework construction in China].

OBJECTIVE: Through investigating food safety standard framework among food safety experts, to summarize the basic elements and principles of food safety standard system, and provide policy advices for food safety standards framework. METHODS: A survey was carried out among 415 experts from government, professional institutions and the food industry/enterprises using the National Food Safety Standard System Construction Consultation Questionnaire designed in the name of the Secretariat of National Food Safety Standard Committee. RESULTS: Experts have different advices in each group about the principles of food product standards, food additive product standards, food related product standards, hygienic practice, test methods. According to the results, the best solution not only may reflect experts awareness of the work of food safety standards situation, but also provide advices for setting and revision of food safety standards for the next. CONCLUSION: Through experts investigation, the framework and guiding principles of food safety standard had been built.

[Quantitative risk assessment of Listeria monocytogenes in bulk cooked meat products].

OBJECTIVE: To conduct a quantitative risk assessment for Listeria monocytogenes in bulk cooked meat products in China. METHODS: The data on the contamination level of Listeria monocytogenes in cooked meat products was from national foodborne disease surveillance network, involving a total of 841 samples. All the samples were detected by a qualitative method and 97 samples among them were detected using a quantitative method. The intake data of cooked meats was from Chinese National Nutrition and Health Survey in 2002 and population data in the monitoring sites was collected from National Bureau of Statistics in 2008 to estimate the composition of the population of different ages, which would be the base of assessing the probability of listeriosis in the different subpopulations. Using @Risk software to estimate the risk of listeriosis caused by consuming deli meats for different subpopulation (0 - 4 years old, 5 - 64 years old and 65 years and older) by quantitative risk assessments which involved hazard identification, hazard characterization, exposure assessment and risk characterization and conduct sensitivity analysis. RESULTS: The contamination level of Listeria monocytogenes in the most of samples (96.08%, 808/841) was less than 3 MPN/g (0.5 lg MPN/g), and the average concentration of Listeria monocytogenes was -0.61 lg CFU/g (90%CI: -1.22 - 0.46 lg CFU/g). Estimated servings of cooked meat consumption for 0 - 4, 5 - 64 and 65 years and older were 5.52 × 10(9), 8.99 × 10(10), 1.01 × 10(10), respectively. Estimated number of cases (median) of listeriosis each year per million people caused by consuming cooked meats in young (0 - 4 years old), intermediate age (5 - 64 years old) and elderly (65 years and older) population were 5.53 × 10(-3), 1.72 × 10(-4), 7.57 × 10(-3), respectively. Results of sensitivity analysis showed that contamination level at retail, serving size of cooked meats, storage time at home, storage temperature and ERG at 5°C were positive factors for the risk of listeriosis (r value was 0.607, 0.408, 0.339, 0.259, 0.183 respectively, P < 0.05). CONCLUSION: Cooked meat products in bulk is a risk food, which could cause listeriosis. Contamination level of Listeria monocytogenes in cooked meat products in bulk is the top risk factor for the listeriosis.

[Analysis of main risk factors causing foodborne diseases in food catering business].

OBJECTIVE: To study main risk factors that cause foodborne diseases in food catering business. METHODS: Data from references and investigations conducted in food catering units were used to establish models which based on @Risk 4.5 with Monte Carlo method referring to food handling practice model (FHPM) to make risk assessment on factors of food contamination in food catering units. The Beta-Poisson models on dose-response relationship to Salmonella (developed by WHO/FAO and United States Department of Agriculture) and Vibrio parahaemolyticus (developed by US FDA) were used in this article to analyze the dose-response relationship of pathogens. RESULTS: The average probability of food poisoning by consuming Salmonella contaminated cooked meat under refrigeration was 1.96 × 10(-4) which was 1/2800 of the food under non-refrigeration (the average probability of food poisoning was 0.35 at room temperature 25°C). The average probability by consuming 6 hours stored meat under room temperature was 0.11 which was 16 times of 2 hours storage (6.79 × 10(-3)). The average probability by consuming contaminated meat without fully cooking was 1.71 × 10(-4) which was 100 times of consuming fully cooked meat (1.88 × 10(-6)). The probability growth of food poisoning by consuming Vibrio parahaemolyticus contaminated fresh seafood was proportional with contamination level and prevalence. CONCLUSION: The primary contamination level, storage temperature and time, cooking process and cross contamination are important factors of catering food safety.

Effect and mechanism of the algicidal bacterium Sulfitobacter porphyrae ZFX1 on the mitigation of harmful algal blooms caused by Prorocentrum donghaiense.

Sulfitobacter porphyrae ZFX1, isolated from surface seawater of the East China Sea during a Prorocentrum donghaiense bloom recession, exhibits high algicidal activity against P. donghaiense. To evaluate the algicidal effect of ZFX1, the algicidal mode and stability were investigated. The results showed that ZFX1 indirectly attacked algae by secreting algicidal compounds, and the algicidal activity of the ZFX1 supernatant was insensitive to different temperatures, light intensities and pH values (pH 3-12). To explore the algicidal mechanism of the ZFX1 supernatant, its effects on the morphological and ultrastructural alterations, photosynthetic capacity, reactive oxygen species (ROS) and antioxidative system of P. donghaiense were investigated. Scanning and transmission electron microscopy revealed that the ZFX1 supernatant destroyed the algal cell membrane structure and caused intracellular leakage. The decrease in the chlorophyll a content and the marked declines in both the photosynthetic efficiency (Fv/Fm) and the electron transport rate (rETR) indicated that the ZFX1 supernatant could damage the photosynthetic system of P. donghaiense. The excessive production of ROS in algal cells demonstrated the oxidative damage triggered by the ZFX1 supernatant. Although the antioxidant defense system of P. donghaiense was activated to scavenge excessive ROS, lipid oxidation occurred. The fatty acid composition profile indicated that the ZFX1 supernatant markedly increased the contents of two saturated fatty acids and a monounsaturated fatty acid and decreased the proportion of two polyunsaturated fatty acids, which resulted in lipids with a lower degree of unsaturation (DU). The decline in the DU decreased the lipid fluidity and rigidified the membrane system, and these effects destroyed the function of the membrane system and ultimately resulted in algal cell death. Therefore, ZFX1 probably plays a key role in mitigating P. donghaiense bloom by inducing lipid oxidation, decreasing the DU of lipids and ultimately destroying the membrane systems of algal cells.

[Public health situation and needs assessment after Wenchuan earthquake in Anxian, Sichuan province].

OBJECTIVE: To explore the public health situation and needs in Anxian after Wenchuan earthquake so as to make an effective strategy for disease control and prevention. METHODS: 69 concentrated settlements with 100 residents were investigated. Probability proportion to size was adopted for sampling of 2200 residents from 687 scattered households (about 440 000 scattered residents). The content of this survey included drinking water, food hygiene, environment sanitation, planning immunity and medical health service, disease surveillance and so on. SPSS 16.0 was used for data analysis, and statistical interpretation was used to describe the results. RESULTS: 90.9% (31/66) resettled residents in Anxian lived in tents, 7.6% (5/66) lived in the movable-plate house, 93.3% (621/666) scattered households lived in tents and 71.9% (446/621) of them lived in tents which were built by residents themselves; the rate of drinking water disinfection in resettlement sites and scattered households were 97.1% (66/68) and 94.6% (650/687); 12.8% scattered residents had mouldy or food; 50% of resettlement sites raised animals; 43.6% (17/39) medical station didn't have bacterin inoculation service; 66.7% (10/15) lacked sufficient disinfection equipment; register rate was 50.0% (33/66) and report rate of symptoms and infectious diseases was 56.1% (37/66). CONCLUSION: There was still some risk of enteric and vector-borne diseases in Anxian, therefore, some tailored measures should be very important.

[Mental health assessment among scattered residents after Wenchuan earthquake in Anxian, Sichuan province].

OBJECTIVE: To explore the mental health status of residents scattered living in Anxian after Wenchuan earthquake so as to provide scientific basis for further mental health intervention. METHODS: A face to face interview was conducted among the scattered residents with designed questionnaire, which had three parts of the physical and emotional reaction, the relax methods and the social care and supports expected. Two-stage probability proportional to size (PPS) sample method was performed to sample 2184 from 0.44 million scattered residents in Anxian. On the basis of statistical description, mental health of different characteristics groups was compared. RESULTS: Three main symptoms of posttraumatic stress disorders in 2184 residents (11.23+/-3.44) were higher than the 103 fire victims in Hunan in 2003 (10.06+/-3.26), three factor scores of SCL-90 (5.76+/-1.74) were higher than normal in 1998 repair mode (n=23 891) (4.72+/-1.44), and the statistical difference was observed (t=10.77, P<0.05; t=706.04, P<0.05). Comparing the mental health of different groups, some significant differences were found by age, gender and education background. CONCLUSION: The earthquake disaster brought prevalent physical and emotional reaction. Elderly people, female, junior students need mental intervention immediately. Therefore, strengthen the mental education and assistance (especially in high risk groups) would be of more significance.

Flocculating properties and potential of Halobacillus sp. strain H9 for the mitigation of Microcystis aeruginosa blooms.

Microcystis aeruginosa can cause harmful algal blooms in freshwaters worldwide. It has already seriously affected human lives and prevented the use of water resources. Therefore, there is an urgent need to develop ecofriendly and effective methods to control and eliminate M. aeruginosa in aquatic environments. In this study, Halobacillus sp. strain H9, a bacterium that showed high M. aeruginosa flocculation activity, was isolated and selected to assess its potential for the removal of M. aeruginosa. The analyses of flocculation activity and mode indicated that the strain H9 induced M. aeruginosa flocculation by secreting active flocculating substance rather than by directly contacting algal cells. A 5% concentration of the H9 supernatant could efficiently flocculate M. aeruginosa cells with a density of up to 5 × 107 cells/mL. Dramatic increases in the zeta potential indicated that charge neutralization could be the mechanism of the flocculation process. The strain H9 flocculated M. aeruginosa with no damage to the algal cell membrane, and did not result in microcystin being released into the surrounding environment. The flocculated algal culture was less toxic to zebrafish larvae, suggesting an environmentally friendly benefit of the H9 supernatant. In addition to M. aeruginosa, the H9 strain was also able to flocculate two other species causing harmful algal blooms, Phaeocystis globose and Heterosigma akashiwo. Furthermore, the flocculation activity of the H9 supernatant was stable at different temperatures and over a wide pH range. These characteristics give the H9 strain great potential for mitigating the influences of harmful algal blooms.

[Quantitative microbiological risk assessment of Salmonella spp. in connmmon catering foods].

OBJECTIVE: To study the relationship between foodborne diseases (FBD) and contamination of Salmonella spp. in catering foods, quantitative microbiological risk assessment (QMRA) of Salmonella spp. was used to evaluate the food material or the ready to eat food. METHODS: The contamination data of Salmonella spp. in 10 896 food samples of 9 categories of food which were collected by National Food Contamination and Food Borne Disease Surveillance Net, combining with diet consumption data from National Food Nutrition Survey in 2002, were analyzed by the microbiological risk assessment model developed by WHO/FAO or FDA/FSIS of US to predict probability of FBD. RESULTS: The results of MRA showed that the probability of salmonellosis by consuming ready to eat meat in summer and autumn was 0.20, much higher than the other foods. Although the contamination level in raw poultry was higher than meat, the probability of salmonellosis by raw poultry (9.11 x 10(-6)) was lower than meat (3.14 x 10(-5)) because of the low consumption volume. CONCLUSION: Probability of FBD was significantly correlated with the volume of food consumption, the status of economy and bacteria contamination level. The level of FBD in summer season was higher than in winter and spring because of ambient temperature.

[Foodborne diseases occurred in 2003--report of the National Foodborne Diseases Surveillance System, China].

OBJECTIVE: To study the foodborne disease outbreaks in the areas covered by National Foodborne Disease Surveillance System. METHODS: Total 13 provinces were included in the surveillance system, and the foodborne disease data in 2003 was collected. RESULTS: A total of 802 outbreaks of foodborne disease were reported. These outbreaks caused a reported 17462 persons to become ill. Among outbreaks for which the etiology was determined, bacterial pathogens caused the largest percentage of outbreaks (46.4%) and the largest percentage of cases (60.4%). Vibrio parahaemolyticus (40.1%) accounted for the largest number of outbreaks and cases. Chemical agents caused 24.1% of outbreaks and 13.9% of cases. CONCLUSION: More work needs to be done to improve the foodborne disease surveillance system.