Realizing strong light-matter interactions between single nanoparticle plasmons and molecular excitons at ambient conditions

Realizing strong light-matter interactions between individual 2-level systems and resonating cavities in atomic and solid state systems opens up possibilities to study optical nonlinearities on a single photon level, which can be useful for future quantum information processing networks. However, these efforts have been hampered by the unfavorable experimental conditions, such as cryogenic temperatures and ultrahigh vacuum, required to study such systems and phenomena. Although several attempts to realize strong light-matter interactions at room-temperature using so-called plasmon resonances have been made, successful realizations on the single nanoparticle level are still lacking. Here, we demonstrate strong coupling between plasmons confined within a single silver nanoprism and excitons in molecular J-aggregates at ambient conditions. Our findings show that the deep subwavelength mode volumes, $V$, together with high quality factors, $Q$, associated with plasmons in the nanoprisms result in strong coupling figure-of-merit -- $Q/\sqrt{V}$ as high as $\sim6\times10^{3}$~$\mu$m$^{-3/2}$ -- a value comparable to state-of-art photonic crystal and microring resonator cavities, thereby suggesting that plasmonic nanocavities and specifically silver nanoprisms can be used for room-temperature quantum optics

Suppression of photo-oxidation of organic chromophores by strong coupling to plasmonic nanoantennas

Intermixed light-matter quasiparticles - polaritons - possess unique optical properties owned to their compositional nature. These intriguing hybrid states have been extensively studied over the past decades in a wide range of realizations aiming at both basic science and emerging applications. However, recently it has been demonstrated that not only optical, but also material-related properties, such as chemical reactivity and charge transport, may be significantly altered in the strong coupling regime of light-matter interactions. Here, we show that a nanoscale system, comprised of a plasmonic nanoprism strongly coupled to excitons in J-aggregated form of organic chromophores, experiences modified excited state dynamics and therefore modified photo-chemical reactivity. Our experimental results reveal that photobleaching, one of the most fundamental photochemical reactions, can be effectively controlled and suppressed by the degree of plasmon-exciton coupling and detuning. In particular, we observe a 100-fold stabilization of organic dyes for the red-detuned nanoparticles. Our findings contribute to understanding of photochemical properties in the strong coupling regime and may find important implications for the performance and improved stability of optical devices incorporating organic dyes.Comment: 5 figures; includes Supplementary Material

Candidate locus analysis of the TERT-CLPTM1L cancer risk region on chromosome 5p15 identifies multiple independent variants associated with endometrial cancer risk.

Several studies have reported associations between multiple cancer types and single-nucleotide polymorphisms (SNPs) on chromosome 5p15, which harbours TERT and CLPTM1L, but no such association has been reported with endometrial cancer. To evaluate the role of genetic variants at the TERT-CLPTM1L region in endometrial cancer risk, we carried out comprehensive fine-mapping analyses of genotyped and imputed SNPs using a custom Illumina iSelect array which includes dense SNP coverage of this region. We examined 396 SNPs (113 genotyped, 283 imputed) in 4,401 endometrial cancer cases and 28,758 controls. Single-SNP and forward/backward logistic regression models suggested evidence for three variants independently associated with endometrial cancer risk (P = 4.9 × 10(-6) to P = 7.7 × 10(-5)). Only one falls into a haplotype previously associated with other cancer types (rs7705526, in TERT intron 1), and this SNP has been shown to alter TERT promoter activity. One of the novel associations (rs13174814) maps to a second region in the TERT promoter and the other (rs62329728) is in the promoter region of CLPTM1L; neither are correlated with previously reported cancer-associated SNPs. Using TCGA RNASeq data, we found significantly increased expression of both TERT and CLPTM1L in endometrial cancer tissue compared with normal tissue (TERT P = 1.5 × 10(-18), CLPTM1L P = 1.5 × 10(-19)). Our study thus reports a novel endometrial cancer risk locus and expands the spectrum of cancer types associated with genetic variation at 5p15, further highlighting the importance of this region for cancer susceptibility.This work was supported by the NHMRC Project Grant (ID#1031333). This work was also supported by Cancer Research UK (C1287/A10118, C1287/A 10710, C12292/A11174, C1281/A12014, C5047/A8384, C5047/A15007, C5047/A10692)This is the published version. It first appeared at http://link.springer.com/article/10.1007%2Fs00439-014-1515-4

Evaluation of Different Treatments for Appendiceal Abscess in Children

Introduction: Despite the high incidence of appendicitis, the diagnosis is often delayed in children. A delayed diagnosis may lead to perforation and formation of an abscess. The treatment of an appendiceal abscess is still a debatable subject and studies have not agreed on what strategy to use. Some prefer immediate operation, whereas others advocate conservative management with or without interval appendectomy. The aim of this study was to evaluate patients treated for appendicular abscess, in order to possibly identify the best treatment algorithm. Method: Medical charts of pediatric patients (<18 years of age) treated for appendiceal abscess between January 2010 and August 2014 were retrospectively studied. The patients were divided into groups based on the type of management; conservative or surgical treatment. Preoperative patient parameters, abscess characteristics, and outcome were evaluated. Results: There was no difference in age, gender, or preoperative data between the surgically and conservatively managed patients. Among the patients diagnosed before the onset of treatment, there was a significantly poorer outcome in the surgically managed group, with a significantly longer duration of hospital stay: 8.5 (range 5-60) days compared to 6 (range 2–10) days (p=0.02), and significantly more complications: 36% compared to 0% (p=0.04). Further, treatment failure seemed to be more common in surgically managed patients with a rate of 25% compared to 0%, however, this was not statistically significant. Conclusion: Conservative management seems to be more beneficial than early surgical intervention in children with appendiceal abscess. Large

Molecular Profiling for Predictors of Radiosensitivity in Patients with Breast or Head-and-Neck Cancer

International audienceNearly half of all cancers are treated with radiotherapy alone or in combination with other treatments, where damage to normal tissues is a limiting factor for the treatment. Radiotherapy-induced adverse health effects, mostly of importance for cancer patients with long-term survival, may appear during or long time after finishing radiotherapy and depend on the patient’s radiosensitivity. Currently, there is no assay available that can reliably predict the individual’s response to radiotherapy. We profiled two study sets from breast (n = 29) and head-and-neck cancer patients (n = 74) that included radiosensitive patients and matched radioresistant controls.. We studied 55 single nucleotide polymorphisms (SNPs) in 33 genes by DNA genotyping and 130 circulating proteins by affinity-based plasma proteomics. In both study sets, we discovered several plasma proteins with the predictive power to find radiosensitive patients (adjusted p < 0.05) and validated the two most predictive proteins (THPO and STIM1) by sandwich immunoassays. By integrating genotypic and proteomic data into an analysis model, it was found that the proteins CHIT1, PDGFB, PNKD, RP2, SERPINC1, SLC4A, STIM1, and THPO, as well as the VEGFA gene variant rs69947, predicted radiosensitivity of our breast cancer (AUC = 0.76) and head-and-neck cancer (AUC = 0.89) patients. In conclusion, circulating proteins and a SNP variant of VEGFA suggest that processes such as vascular growth capacity, immune response, DNA repair and oxidative stress/hypoxia may be involved in an individual’s risk of experiencing radiation-induced toxicity