Complementarity, quantum erasure and delayed choice with modified Mach-Zehnder interferometers

Often cited dictums in Quantum Mechanics include "observation disturbance causes loss of interference" and "ignorance is interference". In this paper we propose and describe a series of experiments with modified Mach-Zehnder interferometers showing that one has to be careful when applying such dictums. We are able to show that without interacting in any way with the light quantum (or quanta) expected to behave "wave-like", interference fringes can be lost by simply gaining (or having the potential to gain) the which-path knowledge. Erasing this information may revive the interference fringes. Delayed choice can be added, arriving to an experiment in line with Wheeler's original proposal. We also show that ignorance is not always synonym with having the interference fringes. The often-invoked "collapse of the wavefunction" is found to be a non-necessary ingredient to describe our experiments.Comment: 8 pages, 3 figures; to appear in EPJ

Clinical development of new drug-radiotherapy combinations.

In countries with the best cancer outcomes, approximately 60% of patients receive radiotherapy as part of their treatment, which is one of the most cost-effective cancer treatments. Notably, around 40% of cancer cures include the use of radiotherapy, either as a single modality or combined with other treatments. Radiotherapy can provide enormous benefit to patients with cancer. In the past decade, significant technical advances, such as image-guided radiotherapy, intensity-modulated radiotherapy, stereotactic radiotherapy, and proton therapy enable higher doses of radiotherapy to be delivered to the tumour with significantly lower doses to normal surrounding tissues. However, apart from the combination of traditional cytotoxic chemotherapy with radiotherapy, little progress has been made in identifying and defining optimal targeted therapy and radiotherapy combinations to improve the efficacy of cancer treatment. The National Cancer Research Institute Clinical and Translational Radiotherapy Research Working Group (CTRad) formed a Joint Working Group with representatives from academia, industry, patient groups and regulatory bodies to address this lack of progress and to publish recommendations for future clinical research. Herein, we highlight the Working Group's consensus recommendations to increase the number of novel drugs being successfully registered in combination with radiotherapy to improve clinical outcomes for patients with cancer.National Institute for Health ResearchThis is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/nrclinonc.2016.7

Failure-specific prognostic factors after continuous hyperfractionated accelerated radiotherapy (CHART) or conventional radiotherapy in locally advanced nonsmall-cell lung cancer: A competing risks analysis

The aim of this study was to identify possible failure-specific prognostic factors in non-small-cell lung cancer. Clinical outcome was analysed in 549 patients participating in the randomized controlled trial of CHART vs conventional radiotherapy. Local failure and distant failure with or without concurrent local relapse were subjected to a competing risk analysis using an accelerated failure-time model with a log-logistic hazard function. Randomization to CHART (2P = 0.005), increasing age (2P = 0.036) and female sex (2P = 0.09) was all associated with a prolonged interval to failure. Advanced clinical stage was associated with a decreased interval to failure (2P = 0.004) and a significantly increased risk (2P = 0.009) of failing in distant rather than in local position. From this model, prognostic indices for local and distant failure were estimated for each individual patient. Competing risk analysis allows identification of patients with different failure patterns, and may provide a means of stratifying patients for intensified local or systemic therapy. (C) 2001 Cancer Research Campaign

Optimization of follow-up timing from study of patterns of first failure after primary treatment. An example from patients with NSCLC: A study of the REACT working group of ESTRO

Background and purpose: The European Society for Therapeutic Radiology and Oncology was funded by the EU for a project on Recording providing Education, and Ameliorating the Consequences of Treatment (REACT). An important aim of follow-up (FU) after treatment for cancer is to detect various events associated with disease recurrence or metastatic spread or severe treatment-related complications as early as possible. Each tumour type may show a specific pattern and timing of these events related to different prognostic factors. The aim of this study was to propose a way of defining an optimal timing schedule for follow-up after treatment based on the analysis of failure patterns determined from follow-up data from prospective clinical trials

Optimization in high dose rate brachytherapy for utero-vaginal applications.

Background and purpose: High dose rate (HDR) remote afterloading intracavitary brachytherapy is an effective treatment modality which has some advantages over low dose rate (LDR) techniques for gynaecological cancer. Optimization is one of the possibilities of modem brachytherapy techniques, especially the stepping source technology. The use of the term 'optimization' implies achieving the desired optimum dose distribution by changing some parameters of the treatment. The aim of this study was to theoretically evaluate the optimization possibilities by modifying dwell times and dwell positions of the uterine and vaginal sources

Molecular biomarkers and site of first recurrence after radiotherapy for head and neck cancer

The prognostic significance of a panel of molecular biomarkers in head and neck squamous cell carcinoma (HNSCC) for first failure site (primary (T), nodal (N) or distant (M)) was analysed in 309 patients randomised to continuous hyperfractionated accelerated radiotherapy (CHART) vs. conventionally fractionated radiotherapy. Multivariate competing risks analysis was performed using an accelerated failure-time model. First-order interactions between each marker and trial arm were also tested. Bcl2-positivity increased the time to T- and N-failures, increasing cyclin D I score decreased the time to N-failures. A random proliferative pattern and low Ki-67 decreased the time to M-failures. A high CD31 score was associated with a significantly longer time to T-failure after CHART, but not after conventional fractionation. Risks of T-, N- and M-failures could be estimated for individual patients. Competing risks analysis of failure sites allows the rational selection of patients for more aggressive loco-regional or systemic therapy. (C) 2004 Elsevier Ltd. All rights reserved