Numerical simulation and optimization of high strength steel bumper forming process and springback control

Production of high strength steel bumper can greatly enhance the occupant safety.However,it is very hard to form high strength steel plate.There is rare domestic successful reference.The hot stamping technology aboard increases costs significantly,and the efficiency is low.Therefore,the only solution is combining advanced numerical simulation technology with current adjusting stamping process.The cold forming process of a sedan’s high strength steel bumper is simulated by FEM software Dynaform and the results show that springback and crack are the main defects.A law is summed up by researching the influence of different shapes of addendums on part forming and springback.Finally,the optimized shape of addendum is obtained by adjusting the addendum and adding convex roofs.It provides references for manufacturing similar high strength steel parts.     

Advances in Marine Microbial Symbionts in the China Sea and Related Pharmaceutical Metabolites

Marine animals and plants such as sponges, sea squirts, corals, worms and algae host diverse and abundant symbiotic microorganisms. Marine microbial symbionts are possible the true producers or take part in the biosynthesis of some bioactive marine natural products isolated from the marine organism hosts. Investigation of the pharmaceutical metabolites may reveal the biosynthesis mechanisms of related natural products and solve the current problem of supply limitation in marine drug development. This paper reviews the advances in diversity revelation, biological activity and related pharmaceutical metabolites, and functional genes of marine microbial symbionts from the China Sea.     

Impact of Fusarium oxysporum on the holoparasitic weed Phelipanche ramosa: biocontrol efficacy under field-grown conditions

Under the changing agro-climatic conditions of western Europe, the parasitic weed Phelipanche ramosa infests host crops such as tomato, hemp, tobacco and oilseed rape at an increasing rate. A Fusarium oxysporum isolate (FOG), that had effectively reduced the parasite's incidence under controlled environmental conditions, was tested in different granular formulations (pesta granules, alginate pellets) on P. ramosa parasitising tobacco under field-grown conditions. FOG reduced number and biomass of P. ramosa shoots by between 50% and 70% in three consecutive years (2006–2008). A single pesta application did not show consistent results throughout seasons; 50% reduction of P. ramosa biomass (DM) in the first year could not be repeated in the following years (20–30%). An alginate formulation applied alone performed better. However, a combination of pesta granules with alginate pellets had the highest reliable control efficacy (60–70%) of all treatments in two seasons, compared with the untreated control. Fungal population counts in soil samples did not show a close correlation to biocontrol efficacy. To understand field performance of this biocontrol agent, additional glasshouse and laboratory studies were conducted using soil from the experimental site. The glasshouse study revealed some fungistatic effects of the field soil that partly explain the reduced efficacy (-40%) in the field compared with results obtained under controlled conditions. Results show the potential of FOG for P. ramosa control. Because formulation affected the biocontrol efficacy, it may be worthwhile to test how the delivery system can be changed in order to achieve increased disease development in the field.     

基于Proteus的同步器倾斜性检测系统设计

为了满足同步器总成检测要求,文章设计了一套基于同步器齿毂齿套倾斜性检测系统。文章不仅完成同步器倾斜性检测系统机械结构、硬件、软件的设计,还介绍了所研制的计算机和单片机控制的汽车同步器总成倾斜量检测系统、检测原理及试验仿真。此外,还提出基于Proteus的系统开发方法,应用Proteus进行原理图设计,根据Proteus中的电子元件特性模拟了检测系统的微位移传感器,并利用Proteus与Keil的联合调试进行仿真分析,得出仿真数据。相比于其他检测装置,该系统在检测精度和自动化方面更臻完美。     

Effects of organic wastes,Glomus intraradices andPseudomonas putida on the growth of tomato and on the reproduction of the Root-knot nematodeMeloidogyne incognita

Effects of organic wastes (biosolids, horse manure, sawdust and neem leaf litter [NLL]), an arbuscular mycorrhizal (AM) fungusGlomus intraradices, and a plant growth-promoting rhizobacteriumPseudomonas putida, were studied on the growth of tomato and on the reproduction ofMeloidogvne incognita. Pseudomonas putida andG. intraradices promoted tomato growth in nematode-infected and nematode-free plants but growth promotion was higher in the infected ones. WhenP. putida andG. intraradices were applied together, the increase in tomato growth was greater than when either agent was applied alone. Of the organic wastes, NLL was better in improving tomato growth of nematode-infected plants followed by biosolids, horse manure and sawdust. Combined use of NLL withP. putida plusG. intraradices was best in improving growth of the infected plants. Root colonization byP. putida was increased more when inoculated withG. intraradices than when inoculated singly. Of the organic wastes, use of sawdust withP. putida caused a greater increase in root colonization by fluorescent pseudomonads followed by NLL, horse manure and biosolids. Nematode parasitism had an adverse effect on root colonization byP. putida. Inoculation ofP. putida and organic wastes increased the root colonization caused by the AM fungus.P. putida was better in reducing galling and nematode multiplication thanG. intraradices, whereas use of the two together was better than that of either of them alone. Among organic wastes, NLL was better in reducing galling and nematode multiplication followed by biosolids, horse manure and sawdust. Combined use of NLL withP. putida plusG. intraradices was better in reducing galling and nematode multiplication than any other treatment.     

Detection and Control of a Nosocomial Outbreak Caused by Salmonella Newport at a Large Animal Hospital

Background: Nosocomial salmonellosis is often assumed to occur because infection control and surveillance practices are inadequate, but published evidence is lacking to support the related contention that rigorous application of these practices can impact the severity of outbreaks. Objective: Describe active surveillance, early recognition, and intensive mitigation efforts used in an effort to control an outbreak of nosocomial Salmonella enterica serotype Newport infections without hospital closure. Animals: Large animals hospitalized at a referral hospital. Methods: This prospective outbreak investigation was initiated when Salmonella Newport infections were detected among hospitalized animals by active surveillance. Data were analyzed to identify temporal and spatial patterns for epidemic spread of Salmonella in the hospital. Mitigation efforts were aggressively adjusted in response to surveillance data. Genetic relatedness of isolates was investigated by pulsed‐field gel electrophoresis. Results: Of 145 large animals sampled, 8 (5.6%) were infected with the Salmonella strain associated with this outbreak, and all but 1 shed Salmonella in the absence of or before the onset of disease. This strain was recovered from 14.2% (42/295) of environmental samples (ENV samples), indicating that widespread environmental contamination had occurred. Isolates of Salmonella Newport obtained from infected animals and the environment were genetically indistinguishable, confirming clonal dissemination. Conclusions and Clinical Importance: Active surveillance allowed early detection of nosocomial Salmonella transmission and hospital contamination. Use of aggressive interventions was followed by cessation of transmission. Active surveillance can allow earlier recognition and mitigation compared with programs by only sampling of clinically affected animals.     

What can pest management learn from laboratory animal ethics?

There remains a lack of a clear overarching policy framework for decision‐making in pest control programmes. In comparison, ethical principles have been extensively developed for scientific procedures, such as those underlying the UK's Animals (Scientific Procedures) Act 1986. This paper assesses the extent to which the principles and methodology underlying the act and secondary guidance could be used to provide principles of rodent management. Useful principles include that any programme has a legitimate purpose; that methods are used only if the harms are outweighed by the benefits; that harms are minimised by refinement, replacement and reduction and that there is personal responsibility. The usefulness and implications for pest control of each principle and the overall approach are discussed. Copyright © 2009 Society of Chemical Industry     

大规模细胞培养中控制污染的举措

从人员培训、环境控制、百级台的无菌操作、原辅材料的管理等方面介绍了大规模细胞培养中避免污染的举措。     

Potential Pharmacological Resources: Natural Bioactive Compounds from Marine-Derived Fungi

In recent years, a considerable number of structurally unique metabolites with biological and pharmacological activities have been isolated from the marine-derived fungi, such as polyketides, alkaloids, peptides, lactones, terpenoids and steroids. Some of these compounds have anticancer, antibacterial, antifungal, antiviral, anti-inflammatory, antioxidant, antibiotic and cytotoxic properties. This review partially summarizes the new bioactive compounds from marine-derived fungi with classification according to the sources of fungi and their biological activities. Those fungi found from 2014 to the present are discussed.