Economic and social powers of the European Union and the member states : subordinate or coordinate relationship?

Digitised version produced by the EUI Library and made available online in 2020

Single microwave photon detection with a trapped electron

We investigate theoretically the use of an electron in a Penning trap as a detector of single microwave photons. At the University of Sussex we are developing a chip Penning trap technology, designed to be integrated within quantum circuits. Microwave photons are guided into the trap and interact with the electron’s quantum cyclotron motion. This is an electric dipole transition, where the near field of the microwave radiation induces quantum jumps of the cyclotron harmonic oscillator. The quantum jumps can be monitored using the continuous Stern-Gerlach effect, providing the quantum non demolition signal of the microwave quanta. We calculate the quantum efficiency of photon detection and discuss the main features and technical challenges for the trapped electron as a quantum microwave sensor

Effects of the Partial Replacement of Cement with Cassava Peel Ash and Rice Husk Ash on Concrete

Being the third-largest emitter of greenhouse gases (GHG) globally, the cement industry has come under scrutiny by the international community lately. In a bid to remedy the situation, researchers worldwide are keen on finding alternative materials to partially or fully replace Portland cement in concrete production. Materials such as industrial waste, biological waste, agricultural and domestic waste have been used. In this study, a ternary blend of Ordinary Portland Cement, Cassava Peel Ash (CPA), and Rice Husk Ash (RHA) were introduced as the binder System in concrete production to reduce the use of Portland cement. The concrete mix was prepared to put CPA at 5% for all combinations while the RHA was varied from 0 to 25% of the total binder content. With a 0.65 water/binder ratio, an optimum strength was reached at 20% replacement of CPA (5%) and RHA (15%). The partial replacement of cement with CPA – RHA in concrete has also positively affected concrete's water absorption properties. From the use of these materials, GHG emissions are reduced, and the waste generated from the pile of cassava peel and rice husk is eliminated

Effects of the Partial Replacement of Cement with Cassava Peel Ash and Rice Husk Ash on Concrete

Being the third-largest emitter of greenhouse gases (GHG) globally, the cement industry has come under scrutiny by the international community lately. In a bid to remedy the situation, researchers worldwide are keen on finding alternative materials to partially or fully replace Portland cement in concrete production. Materials such as industrial waste, biological waste, agricultural and domestic waste have been used. In this study, a ternary blend of Ordinary Portland Cement, Cassava Peel Ash (CPA), and Rice Husk Ash (RHA) were introduced as the binder System in concrete production to reduce the use of Portland cement. The concrete mix was prepared to put CPA at 5% for all combinations while the RHA was varied from 0 to 25% of the total binder content. With a 0.65 water/binder ratio, an optimum strength was reached at 20% replacement of CPA (5%) and RHA (15%). The partial replacement of cement with CPA – RHA in concrete has also positively affected concrete's water absorption properties. From the use of these materials, GHG emissions are reduced, and the waste generated from the pile of cassava peel and rice husk is eliminated

Successful management of elderly breast cancer patients treated without radiotherapy

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Breast cancer in the elderly may follow a less aggressive course. There are data suggesting that radiotherapy (RT) following breast conserving surgery (BCS) for invasive carcinoma may not be necessary in some elderly patients. The addition of RT to surgery might constitute an imposition to such patients due to age-related factors. The aim of this study was to assess the efficacy of BCS without adjuvant RT in this group of patients. Patients and methods A retrospective review of 92 elderly (median age 75 years; range: 70 – 87 years) patients (analysed as 93 'patients' due to one patient having bilateral cancers) managed in a dedicated breast clinic and who underwent BCS for invasive carcinoma was carried out. Eighty-three patients did not receive postoperative RT to the breast (no-RT group) whereas the remaining 10 had RT (RT-group). Results The median age in this group was 75 (range 70 – 87) years. The mean tumour size was 18 mm with a median follow-up of 37 (range 6 – 142) months. In the no RT group, adjuvant endocrine therapy with tamoxifen was given to 40/53 patients. No patients in the oestrogen receptor (ER) negative group received tamoxifen. The local recurrence (LR) rate in this group was 8.4% (2.4% per year, n = 7/83), with median time to LR of 17 months. In this no-RT group LR was correlated to ER status (2/53 ER+, 5/26ER-, p = 0.024) and margins of excision (n = 1/54 >5 mm, 2/17 1–5 mm, 4/12 <1 mm, p = 0.001). Within the ER positive group the LR rate was 0.92% per annum (0.62% per annum in patients treated with adjuvant tamoxifen, regardless of margin status). Breast cancer specific survival was correlated to histological grade (p < 0.05) and ER status (p < 0.05). Conclusion It would appear that omission of RT following successful BCS in elderly patients with ER positive tumours receiving adjuvant tamoxifen may be acceptable. The LR rate as shown in this retrospective study is highly comparable to that of younger patients treated by conventional therapy. This concept is now being evaluated prospectively following a change in treatment practice.Published versio

Planar, strong magnetic field source for a chip ion trap

We present a planar, scalable magnetic field source, originally conceived for a chip ion trap. It consists of two symmetric sections, each with several independent currents arranged in coplanar, concentric rectangular loops. The currents allow for tuning the strength of the field and its lowest-order derivatives at one discretional position along the source’s vertical symmetry axis, a few mm above its surface. We describe the construction and calibration of the device and the cryogenic setup. The two most important current configurations for a Penning ion trap, the homogeneous field and the magnetic bottle, are investigated experimentally. Homogeneous fields around 0.5 T are routinely reached. We discuss the maximum attainable field, and we briefly describe ongoing further developments aiming at homogeneous fields well above 1 T

Coherent coupling of a trapped electron to a distant superconducting microwave cavity

We investigate theoretically the coupling of a single electron in a planar Penning trap with a remote superconducting microwave cavity. Coupling frequencies around Ω = 2π · 1 MHz can be reached with resonators with a loaded quality factor of Q = 10^5, allowing for the strong coupling regime. The electron and the cavity form a system of two coupled quantum harmonic oscillators. This is a hybrid and linear microwave quantum network. We show that the coherent interaction can be sustained over distances of a few mm up to several cm. Similar to classical linear MW circuits, the coherent quantum exchange of photons is ruled by the impedances of the electron and cavity. As one concrete application, we discuss the entanglement of the cyclotron motions of two electrons located in two separate traps