Entanglement of separate nitrogen-vacancy centers coupled to a whispering-gallery mode cavity

We present a quantum electrodynamical model involving nitrogen-vacancy centers coupled to a whispering-gallery mode cavity. Two schemes are considered to create W state and Bell state, respectively. One of the schemes makes use of the Raman transition with the cavity field virtually excited; The other enables the Bell state preparation and quantum information transfer by virtue of dark state evolution and adiabatic passage, which is tolerant to ambient noise and experimental parameter fluctuations. We justify our schemes by considering the experimental feasibility and challenge using currently available technology.Comment: 8 pages and 5 figure

Assessing low energy school buildings using the new Building Bulletin 101

This paper reports an assessment of a school building design using the newly published Building Bulletin 101 2018. The requirements on thermal comfort and CO2 based indoor air quality from this new guidance document are very different from its earlier version published in 2006. Existing research reported that the new requirements are much tougher to meet compared with the previous version. The aim of this research is to examine whether design alternatives on an existing school building with 10 learning and teaching spaces can help in passing the new requirements using dynamic thermal simulation tool - IESVE. It is found that promoting ventilation, shading and night purging can all help mitigating overheating in the ten learning and teaching spaces evaluated. With the ‘as built’ condition, these learning and teaching spaces failed all three overheating criteria from the new BB101. Promoting ventilation can help some of the spaces pass the overheating occurrence criterion but not the overheating severity criteria. With added shading to block excessive solar gains, half of the evaluated spaces were able to pass the thermal comfort requirement. Boosting the night purging also helps to some extent in bridging the gap against the target requirements on overheating severity, however, there are still spaces which will not pass the comfort requirement. This may indicate that natural ventilation itself may not be able to provide thermal comfort for the given design. CO2 based indoor air quality requirements are less of an issue as higher CO2 concentrations always happen when the outdoor air temperature is low, boosting ventilation using automatic or manual control can easily resolve this. The research also highlights that one of the overheating criteria is much more difficult to meet, the appropriateness of this criterion is therefore in question. As the new BB101 was only launched very recently, it will be subject to further tests and evaluations in order to examine whether it fits for purpose

Seedling salt tolerance in tomato

Soils with higher concentrations of salt are becoming more and more a constraint for many crops to obtain high yields. Wild tomato species, adapted to adverse environments, are a potential reservoir for genes underlying quantitative trait loci (QTL) related to salt tolerance in tomato. In this study two introgression line (IL) libraries derived from two different wild species, Solanum pennellii LA716 and Solanum lycopersicoides LA2951, were used to identify QTLs for salt tolerance in the seedling stage. In the S. pennellii IL library, four major QTLs were identified on chromosomes 6, 7 and 11. In the S. lycopersicoides IL library, six major QTLs were discovered which are located on chromosomes 4, 6, 9 and 12. Co-localization of QTLs on chromosome 6 in the two IL libraries and previously reports hinted that this locus might be conserved in the tomato crop. Three S. pennellii ILs (IL6-2, IL7-1 and IL7-5) harboring QTLs on chromosome 6 and 7 were crossed. Semi-dominance and dominance were shown for these three QTLs, and non-additive and epistatic interactions between them were observe