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201.
The advances in the biotechnology industry, and in biosciences research are impressive by any measure, but it is not sufficient just to continue to make spectacular scientific breakthroughs. It is important that the general public is assisted to keep up with the pace of technological change. Some efforts have been made, but they have not been enough. A public relations strategy is required. The biotechnology industry needs to influence public opinion as well as lead discovery. The aims of a public relations campaign should not be just to inform and convince legislators and regulators, but should target the average consumer of the 21st century. There are two areas where the science community must direct its attention if the international public is to be brought along on this biotechnological odyssey: the compulsory school sector – including teachers, students and policy makers; and key sector groups that can be specifically targeted such as farmers, indigenous peoples, horticulturists, food sector people, health professionals, and in particular, the recently retired. If the potential of biotechnological advances is to be realised, scientists must be proactive in educating the general public. This will also involve educating the educators. No amount of public education will completely remove the opposition to genetic engineering, but with an educated public there is an increased opportunity for a fair debate and scare tactics, half-truths and innuendo will gain less traction.  相似文献   
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Teachers' conscious priorities in selecting topics for teaching rarely include the ‘biology/social science interfaces’; neither are many usually aware of the existence and implications of ‘hidden ideologies’ in the curriculum. This paper gives several examples of such interfaces, and stresses the point that only by redirecting the education of teachers can their awareness and priorities be suitably altered.  相似文献   
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An interactive computer program written in Fortran is described which provides an exercise in the identification of bacteria. The program, IDEN, provides a novel way of enhancing a student's approach to systematic bacteriology and numerical identification procedures. An unknown bacterium is assigned to a student who is provided with a list of possible species and a list of tests which may be carried out. The student's objective is the correct identification of the unknown in the most economical manner. An indication is given concerning the way in which this program can be used to enhance theoretical instruction and practical investigation.  相似文献   
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The simple illuminated monocular low-power microscope described here can be produced for much less than commercially available alternatives  相似文献   
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Abstract. Two graphical models of plant competition, the ‘ghost of competition past’ and the ‘hierarchical’ model are compared using a greatly simplified individual-based forest dynamics simulation. Assumed fundamental niche shapes are used to determine the basic growth responses of the species, but competition alters the realized niche. Differences in the two models, amount of niche overlap, disturbance, and removal and invasion of species are examined in simulation experiments. Without disturbance, the realized niche responses reveal abrupt boundaries between species in all cases, and thus the responses are generally platykurtic to rectangular with little overlap. In some cases overlap through the extension of abundance of weaker competitors into the area of greater resources — dominated by better competitors but still within their fundamental niche — creates skewed distributions, as have been observed and simulated in the past. When species are removed or invade, the abrupt boundaries and the lack of difference in final response shape indicate that past removals may be difficult to detect. This difficulty may be important because former species may be influencing the responses that are observed in common non-equilibrium distributions. Even when assumptions favor the illustration of a competitive hierarchy, actual distributions and dynamics do not differentiate between it and a model of the ghost of competition past.  相似文献   
207.
The kinetic granular temperatures of a binary granular mixture in simple shear flow are calculated by means of the Direct Simulation Monte Carlo method. The results show that the temperature ratio is clearly different from unity (as may be expected since the system is out of equilibrium) and strongly depends on the restitution coefficients as well as on the parameters of the mixture. The influence of the temperature differences on the rheological properties is also discussed. The results are compared with the theoretical predictions obtained from the Boltzmann kinetic theory by using a Sonine polynomial expansion. The comparison shows an excellent agreement over the range of parameters investigated.  相似文献   
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The “Who said what?” protocol is a popular experimental paradigm and has been used for 40?years to study spontaneous mental categorization. This paper offers a crucial methodological improvement to calculate unbiased estimates in multidimensional “Who said what?” studies. Previous studies predominantly corrected for base rates by first correcting the base rates and consequently aggregating errors for the two dimensions separately. The paper demonstrates that this procedure's estimates are biased. A large simulation of over 175,000 experiments and the re-analysis of a pivotal study show that this may increase both false-positive and false-negative error rates in treatment effects and might therefore, respectively, strengthen or weaken evidence for past hypotheses. The paper offers a simple remedy: researchers should first aggregate errors for each dimension and then correct for base rates relying on the method known from single-dimensional studies.  相似文献   
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