Cavity quantum electrodynamics (QED) studies the interaction between a quantum emitter and a single radiation-field mode. When an atom is strongly coupled to a cavity mode, it is possible to realize ...important quantum information processing tasks, such as controlled coherent coupling and entanglement of distinguishable quantum systems. Realizing these tasks in the solid state is clearly desirable, and coupling semiconductor self-assembled quantum dots to monolithic optical cavities is a promising route to this end. However, validating the efficacy of quantum dots in quantum information applications requires confirmation of the quantum nature of the quantum-dot-cavity system in the strong-coupling regime. Here we find such confirmation by observing quantum correlations in photoluminescence from a photonic crystal nanocavity interacting with one, and only one, quantum dot located precisely at the cavity electric field maximum. When off-resonance, photon emission from the cavity mode and quantum-dot excitons is anticorrelated at the level of single quanta, proving that the mode is driven solely by the quantum dot despite an energy mismatch between cavity and excitons. When tuned to resonance, the exciton and cavity enter the strong-coupling regime of cavity QED and the quantum-dot exciton lifetime reduces by a factor of 145. The generated photon stream becomes antibunched, proving that the strongly coupled exciton/photon system is in the quantum regime. Our observations unequivocally show that quantum information tasks are achievable in solid-state cavity QED.
The GlobalFiler™ PCR Amplification Kit is a single multiplex assay that amplifies a set of 24 markers, which encompass the European Standard Set and CODIS (Combined DNA Index System) recommended ...composite set of loci. In addition to more loci and a 6-dye chemistry format, the Master Mix has been formulated to allow higher sample loading volume for trace DNA samples. The GlobalFiler™ Kit has been optimized to deliver high performance on casework samples, while also delivering fast thermal cycling, with an amplification time of approximately 80 min. Here, we report the results of the developmental validation study which followed the SWGDAM (Scientific Working Group on DNA Analysis Methods) guidelines and includes data for PCR-based studies, sensitivity, species specificity, stability, precision, reproducibility and repeatability, concordance, stutter, DNA mixtures, and performance on mock casework samples. The results validate the multiplex design as well as demonstrate the kit’s robustness, reliability, and suitability as an assay for human identification with casework DNA samples.
This paper presents characteristics of droughts simulated by global climate models (GCMs) under enhanced greenhouse gases conditions. We used a drought index called the Reconnaissance Drought Index ...(RDI) which takes both rainfall and potential evapotranspiration into account to investigate variations of droughts among 12 regions in Australia. The RDI was applied to simulated climate variables from 14 GCMs performed for the IPCC 4th Assessment Report.
The results show a general increase in drought areal extent and/or frequency for most regions. However, the increases are not significant over the North West, North Queensland, Queensland East Coast and Central Queensland. For most regions, the change beyond 2030 is larger than that prior to 2030, but the uncertainty in the projections also increases with time. By 2030, there is a
likely (>66% probability) risk of twice or more drought affected area and/or twice as often drought frequency over South West Western Australia. By 2050, this will include the Murray-Darling Basin, South Australia and Victoria, and by 2070 this will extend to New South Wales and Tasmania. For North Queensland such a risk is
unlikely (<33% probability) for the next 100 years. This information can be considered indicative in long-term planning focussing on sustainability.
► Future drought in Australia are estimated through the use of GCMs simulations. ► It assumes the climate system's response to SRES-A1B and A2 is as modelled by GCMs. ► Increases in drought are likely for most regions, but not all of them are significant.
We demonstrate that very few (2-4) quantum dots as a gain medium are sufficient to realize a photonic-crystal laser based on a high-quality nanocavity. Photon correlation measurements show a ...transition from a thermal to a coherent light state proving that lasing action occurs at ultralow thresholds. Observation of lasing is unexpected since the cavity mode is in general not resonant with the discrete quantum dot states and emission at those frequencies is suppressed. In this situation, the quasicontinuous quantum dot states become crucial since they provide an energy-transfer channel into the lasing mode, effectively leading to a self-tuned resonance for the gain medium.
The successful development of biomaterials must take into consideration how those surfaces will interact with in vivo processes such as adsorption of endogenous proteins. In this study, we examined ...whether modifying highly adsorbent materials like hydroxyapatite (HA) with RGD peptides would improve mesenchymal stem cell (MSC) adhesion. We found that RGD, alone, was not sufficient to promote full cell spreading. However, given that RGD-modified HA will likely adsorb osteogenic serum proteins in vivo, we evaluated MSC behavior on HA pre-coated with RGD, then over-coated with serum (RGD/FBS). Interestingly, RGD/FBS coatings additively stimulated MSC attachment and spreading compared to either coating alone, but only at low RGD coating concentrations. High RGD concentrations inhibited cell attachment, and completely eliminated cell spreading on RGD/FBS surfaces. To better understand the mechanism by which RGD and adsorbed serum proteins interactively regulate cell behavior, we monitored the deposition of fibronectin (FN) from serum onto HA pre-coated with increasing RGD concentrations. These studies showed that high RGD concentrations did not inhibit FN adsorption, therefore cell spreading is attenuated by mechanisms other than lack of FN availability. Collectively, our results suggest a potential therapeutic benefit for functionalizing HA with RGD, however such a benefit will likely depend upon the RGD density.
The Gram-negative bacterium
is a common member of the human gut microbiota that colonizes multiple host niches and can influence human physiology through a variety of mechanisms. Identification of ...genes that enable
to grow across a range of host environments has been impeded in part by the relatively limited genetic tractability of this species. We have developed a high-throughput genetic resource for a
strain isolated from a UC pouchitis patient. Bile acids limit microbial growth and are altered in abundance in UC pouches, where
often blooms. Using this resource, we uncovered pathways and processes that impact
fitness in bile and that may contribute to population expansions during bouts of gut inflammation.
Highlights • Developmental validation following SWGDAM guidelines of the GlobalFiler® Express PCR Amplification Kit. • First 6-dye, 24-locus STR kit that contains all the “required” and “recommended” ...loci proposed by the CODIS Core Loci Working Group. • Direct amplification from reference samples with thermal cycling time under 45 min. • Concordance maintained between GlobalFiler® Express Kit and AmpFLSTR® Identifiler® Direct and NGM SElect™ Express Kits.
We examined the effects of past and future climate change on natural snow cover in southeastern mainland Australia and assessed the role of snowmaking in adapting to projected changes in snow ...conditions. Snow-depth data from 4 alpine sites from 1957 to 2002 indicated a weak decline in maximum snow depths at 3 sites and a moderate decline in mid- to late-season snow depths (August to September). Low-impact and high-impact climate change scenarios were prepared for 2020 and 2050 and used as input for a climate-driven snow model. The total area with an average of at least 1 d of snow cover per year was projected to decrease by 10 to 39% by 2020, and by 22 to 85% by 2050. By 2020, the length of the ski season was projected to have decreased by 10 to 60%, while by 2050 the decrease was 15 to 99%. Based on target snow-depth profiles from May to September nominated by snowmaking managers at various ski resorts, the snow model simulated the amount of snow that is needed to be made each day, taking into account natural snowfall, snow-melt and the pre-existing natural snow depth. By the year 2020, an increase of 11 to 27% in the number of snow guns would be required for the low impact scenario, and 71 to 200% for the high impact scenario. This corresponds to changes in total snow volume of 5 to 17% for the low impact scenario to 23 to 62% for the high impact scenario. Therefore, with sufficient investment in snow guns, the Australian ski industry may be able to manage the effect of projected climate change on snow cover until at least 2020.
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