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38.
Than PP Prihastuti H Phoulivong S Taylor PW Hyde KD 《Journal of Zhejiang University. Science. B》2008,9(10):764-778
Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical
regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the
species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management.
Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of
Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal
agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches
that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current
taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.
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39.
OBJECTIVE: To examine attitudes, conflicts, images, circumstances, and time-period effects associated with corporal punishment and other forms of adult-to-child violence during the early 20th century in the United States. METHOD: A sample of 147 letters, referencing corporal punishment and dating from 1924 to 1939, were analyzed using both qualitative and quantitative techniques. The letters were addressed to Angelo Patri (1876-1965), a popular child-rearing expert during the interwar years (also known as the Machine Age), and written primarily by middle class parents with everyday worries about child rearing and proper discipline. RESULTS: People who sought advice emphasized the practical significance of corporal punishment over and above the idea that it violated children's rights to be protected against harm. One in four letters cited conflicts with significant others about corporal punishment. Generally, children were perceived as frail, defiant, or feral. Rarely, were they seen as devilish or, conversely, innocent. Children's disobedience and disrespect were cited more than other misbehaviors as reasons for corporal punishment. Age and gender of the focal child varied by time period when letters from the 1920s and 1930s were compared. CONCLUSIONS: A full understanding of parent-to-child violence cannot be achieved without a firm grasp of its genealogy. The growing popularity of child psychology during the Machine Age had a measurable impact on how children were viewed. A utilitarian frame of interpretation was an important part of the everyday "work" associated with child rearing during this time, foreshadowing the tendency today to emphasize efficacy more than rights when evaluating the legitimacy of corporal punishment. 相似文献
40.
One challenge of generating a liquid aerosol is finding an efficient way to break up bulk amounts of the compound into micron-sized droplets. Traditional methods of aerosol generation focus on the principle of creating the liquid droplets by blowing air at high speed over or through a liquid. In this study, a novel micropump droplet generator (MDG) is proposed based on a microfluidics device to produce monodisperse droplets on demand (DoD). The micropump design was employed to both pump the fluid into the air and to encourage droplet breakup and aerosol formation. Computational simulation modeling of the new MDG was developed and validated with comparisons to experimental data for current generators. The device was found to produce an aerosol similar to a vibrating orifice DoD device. Most importantly, the input power required by the newly proposed device (MDG) was several orders of magnitude below existing DoD generators for a similar droplet output. Based on the simulation results obtained in comparison with current DoD generators, the MDG device performed effectively at higher frequencies, smaller nozzle diameters, and regardless of the liquid viscosity of the solution. 相似文献