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Levesley A  Jopson J  Knight C 《The Plant cell》2012,24(4):1306-1315
We provide evidence from a 5-year study to show that a single concerted effort at the start of undergraduate study can have a clear and lasting effect on the attitudes of students toward plant science. Attendance at a week-long residential plant science summer school in the first year of an undergraduate degree resulted in many students changing courses to include more plant science and increased numbers of graduates selecting plant-based PhDs. The evidence shows that the Gatsby Plant Science Summer School has increased the pool of high-quality plant science related PhD applicants in the UK and has had a positive impact on students' career aspirations. The results are discussed within the context of enhancing the pipeline of future plant scientists and reversing the decline of this vulnerable and strategically important subject relevant to addressing food security and other major global challenges. We have shown that a single well-designed and timely intervention can influence future student behavior and as such offers a framework of potential use to other vulnerable disciplines.  相似文献   
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Minimally invasive surgery (MIS) has heralded a revolution in surgical practice, with numerous advantages over open surgery. Nevertheless, it prevents the surgeon from directly touching and manipulating tissue and therefore severely restricts the use of valuable techniques such as palpation. Accordingly a key challenge in MIS is to restore haptic feedback to the surgeon. This paper reviews the state-of-the-art in laparoscopic palpation devices (LPDs) with particular focus on device mechanisms, sensors and data analysis. It concludes by examining the challenges that must be overcome to create effective LPD systems that measure and display haptic information to the surgeon for improved intraoperative assessment.  相似文献   
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Recently seven National Academies of Science produced a report on transgenic plants and world agriculture. The report provides scientific perspectives to the ongoing public debate about the potential role for transgenic technology in world agriculture. In this article, we develop the themes of the report and emphasize the potential for future genetically modified (GM) crops with a poverty focus, emphasizing the potential of GM resistance to plant parasitic nematodes for subsistence potato farmers in Bolivia. We judge that a range of incremental gains to crop yields from many transgenes are valuable for future world security. We advocate the establishment of a standard that GM crops must achieve before they are both biosafe and appropriate for resource-poor farmers and we believe that the best interests of the poor require biotechnologists to work towards that objective.  相似文献   
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Rice (Oryza sativa) is sensitive to salinity, which affects one-fifth of irrigated land worldwide. Reducing sodium and chloride uptake into rice while maintaining potassium uptake are characteristics that would aid growth under saline conditions. We describe genetic determinants of the net quantity of ions transported to the shoot, clearly distinguishing between quantitative trait loci (QTL) for the quantity of ions in a shoot and for those that affect the concentration of an ion in the shoot. The latter coincide with QTL for vegetative growth (vigor) and their interpretation is therefore ambiguous. We distinguished those QTL that are independent of vigor and thus directly indicate quantitative variation in the underlying mechanisms of ion uptake. These QTL independently govern sodium uptake, potassium uptake, and sodium:potassium selectivity. The QTL for sodium and potassium uptake are on different linkage groups (chromosomes). This is consistent with the independent inheritance of sodium and potassium uptake in the mapping population and with the mechanistically different uptake pathways for sodium and potassium in rice under saline conditions (apoplastic leakage and membrane transport, respectively). We report the chromosomal location of ion transport and selectivity traits that are compatible with agronomic needs and we indicate markers to assist selection in a breeding program. Based upon knowledge of the underlying mechanisms of ion uptake in rice, we argue that QTL for sodium transport are likely to act through the control of root development, whereas QTL for potassium uptake are likely to act through the structure or regulation of membrane-sited transport components.  相似文献   
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Experiments showed that minnows, Phoxinus phoxinus, sympatric with pike, Esox lucius, responded more vigorously to alarm substance than minnows from a population with no experience of pike predation in the wild. Minnows from the pike-sympatric (Dorset) population were more likely to hide and less likely to risk feeding than their pike-allopatric (Gwynedd) counterparts. The reaction to alarm substance in the pike-sympatric population was further increased when it was presented along with the visual stimulus of a ‘stalking’ model pike. When the Dorset minnows experienced both alarm substance and the pike model together they reduced their inspection behaviour to a level below that of the Gwynedd minnows. Minnows from the Gwynedd (pike-allopatric) population displayed increased levels of shoaling in the treatments in which alarm substance was used.  相似文献   
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