Conceptual development of a ground-based radio-beacon navigation system for use on the surface of the moon

A spread-spectrum radio-beacon navigation system for use on the lunar surface is described. The subjects discussed are principle of operation and specifications to include power requirements, operating frequencies, weight, size, and range

Scientific mindfulness: a foundation for future themes in international business

We conceptualize new ways to qualify what themes should dominate the future IB research agenda by examining three questions: Whom should we ask? What should we ask and which selection criteria should we apply? What are the contextual forces? We propose scientific mindfulness as the way forward for generating themes in IB research

Ab initio calculation of the neutron-proton mass difference

The existence and stability of atoms rely on the fact that neutrons are more massive than protons. The measured mass difference is only 0.14\% of the average of the two masses. A slightly smaller or larger value would have led to a dramatically different universe. Here, we show that this difference results from the competition between electromagnetic and mass isospin breaking effects. We performed lattice quantum-chromodynamics and quantum-electrodynamics computations with four nondegenerate Wilson fermion flavors and computed the neutron-proton mass-splitting with an accuracy of $300$ kilo-electron volts, which is greater than $0$ by $5$ standard deviations. We also determine the splittings in the $\Sigma$, $\Xi$, $D$ and $\Xi_{cc}$ isospin multiplets, exceeding in some cases the precision of experimental measurements.Comment: 57 pages, 15 figures, 6 tables, revised versio

Clinical relevance of "withdrawal therapy" as a form of hormonal manipulation for breast cancer

<p>Abstract</p> <p>Background</p> <p>It has been shown in in-vitro experiments that "withdrawal" of tamoxifen inhibits growth of tumor cells. However, evidence is scarce when this is extrapolated into clinical context. We report our experience to verify the clinical relevance of "withdrawal therapy".</p> <p>Methods</p> <p>Breast cancer patients since 1998 who fulfilled the following criteria were selected from the departmental database and the case-notes were retrospectively reviewed: (1) estrogen receptor positive, operable primary breast cancer in elderly (age > 70 years), locally advanced or metastatic breast cancer; (2) disease deemed suitable for treatment by hormonal manipulation; (3) disease assessable by UICC criteria; (4) received "withdrawal" from a prior endocrine agent as a form of therapy; (5) on "withdrawal therapy" for ≥ 6 months unless they progressed prior.</p> <p>Results</p> <p>Seventeen patients with median age of 84.3 (53.7-92.5) had "withdrawal therapy" as second to tenth line of treatment following prior endocrine therapy using tamoxifen (n = 10), an aromatase inhibitor (n = 5), megestrol acetate (n = 1) or fulvestrant (n = 1). Ten patients (58.8%) had clinical benefit (CB) (complete response/partial response/stable disease ≥ 6 months) with a median duration of Clinical Benefit (DoCB) of 10+ (7-27) months. Two patients remain on "withdrawal therapy" at the time of analysis.</p> <p>Conclusion</p> <p>"Withdrawal therapy" appears to produce sustained CB in a significant proportion of patients. This applies not only to "withdrawal" from tamoxifen, but also from other categories of endocrine agents. "Withdrawal" from endocrine therapy is, therefore, a viable intercalating option between endocrine agents to minimise resistance and provide additional line of therapy. It should be considered as part of the sequencing of endocrine therapy.</p